/c/3.1
\
%
A
DEMPSTER'S PATENT CANVAS.
In such a country as Great, Britain, any real and sub¬
stantial improvement in an article of prime necessity, one
at first sight should imagine, would meet immediate and
universal patronage. It is, however, a well known fact,
that no new invention, let it be as excellent as possible,
will, or can be, suddenly adopted. People must first be
convinced, by actual experience, that it really possesses
the merits attributed to it. This is an obstacle that every
one, who attempts to introduce any improvenfent, must
lay his account with. It, besides, not unfrequently hap¬
pens, when the invention is of such importance as to af¬
fect the immediate interests of a large class of manufac¬
turers, that methods are fallen upon, so far to prejudice
the public mind, as to prevent any trial of Consequence
taking place during the currency of the patent, if such
lias been obtained ; and the patentee, far from reaping
any profit from his discovery, has only the mortification
to see those very people, with many advantages on their
side, strike into the path that he, alone, had chalked out.
Although nearly five years have elapsed since a patent
was obtained by Cathcart Dempster of St Andrews,
for a most important improvement in the manufacture of
Sail-canvas, yet has he hitherto been only able to establish
its reputation on the East and West coasts of Scotland,
and on board a few East India ships from the port of
London. And even to do thi^ required no small exer¬
tion. For he had not only to surmount the common ob¬
stacles opposed to every one in his situation, but to de¬
monstrate, by actual proof, that an unfavourable report,
which had been industriously circulated, had no founda¬
tion in fact. No one ventured to say that his canvas was
made from coarse or ill prepared materials, or that it was
liable to mildew. But another expedient was fallen upon.
It was roundly asserted that it ‘would stretch a great deal
when put to use, from the peculiar circumstance of its'
being entirely composed of twine. This having some de-
gree of plausibility, had the effect to deter many from
making trial of it, as they were aware that such a fault
would render some kind of sails perfectly useless. The
Patentee now thinks himself fortunate, that this ideal fault
having been strenuously urged, he has at length, on a fair
trial being made, succeeded in convincing many of its fu¬
tility; for he now has it in his power to state, that this, the
only objection that was ever found against his invention,
is more than obviated ; as all who have had actual expe¬
rience of the Patent canvas, declare that it stretches less
than common sailcloth-
Dempster’s Patent Canvas, both in warp and weft,
is made from two-ply twine of nearly the same grist, pro¬
perly prepared by boiling or bleaching before it is weav¬
ed. Its strength is so extraordinary, that No. 3. or 4.
may be safely used in place of No. 1. of common sail¬
cloth ; and with this great advantage, that it is so pli¬
able and easily handed, that those who heretofore went
to sea in a vessel with ten seamen, now find eight perfect¬
ly sufficient; and, from the peculiar circumstance of this
kind of cloth being weaved without the assistance of
starch, or any other kind of dressing whatever, its great
strength is never impaired by the unavoidable bane of
ordinary canvas—rot and mildew. From the closeness
of its texture, it holds a better wind than the other; and
this superiority it continues to maintain in spite of the
weather; for as it has no extraneous matter to lose, it is
evident that the action of the weather will rather tend to
thicken than to thin the fabric, as the twine will gradu¬
ally plump out and fill up the interstices. Common can¬
vas, as is well known, gets more and more porous every i
day, from the rain washing out parj; of the glutinous I
dressing unavoidably used in the process of its manufac¬
ture. Enough of this, however, remains, to be the effi¬
cient cause of mildew. But though it were possible to
remove this leaven of putrefaction, yet, from the impro¬
per construction of the fabric, it cannot last any length of
time ; for, as the grist of the single yams of which this
canvas is made, is four or five times coarser in one direc¬
tion of the fabric than in the other, the fine thread of the
warp will be protruded from the general suiface, (as it
were on a ridge) by. the coarse thread of the weft, and
must be soon cut through by rubbing against every ob¬
ject with which it comes in contact-of course, the cloth
falls to pieces, The patent canvas, on the contrary, be¬
ing altogether composed of twine of nearly the same size,
has a more equal surface and bearing in both directions;
and, therefore, is by no means so much exposed to injury
from friction ; of consequence, it must last a great deal
longer than the other. This last consideration alone
should entitle the Patent Canvas to a decided preference
over the common sort. But when we take into the ac¬
count how much its superior strength tends to the preserve
ation of ufes and peopertt, there surely can be no hesi,
tation.
The small difference of price betwixt this and other
sail-cloth, may, perhaps, act as a restraint on some peo¬
ple } but, to this, may be opposed the old saying, ‘ that
those who buy dearest generally buy cheapest.’ For if
the patentee can believe the uniform testimony of every
one who has made trial of his article for any length of
time, it in the long run (independent of the security it
affords) turns out fifty per cent, cheaper than any other
canvas. In some measure to elucidate this, he begs leave
only to state, that he now supplies a considerable part of
the shipping of Dundee with his canvas ; from which he
will venture to draw the inference, that if this was not
found to be a matter of considerable economy, no such
preference would be given over their own sailcloth, which
forms the chief staple manufacture of the place, and, it ig
believed, is there made in greater quantity than in any
other part of the kingdom.
The present price of Patent Canvas is Subjoined. If,
however, the raw material continues to advance, it must
be increased. But it n?ay be observed, that/ the usual
difference betwixt the Patent, and Common, Boiled or
Bleached Canvas, is about fourpence a yard. There are
two kinds of the Patent Canvas,—Bleached anJ Boiled.
The Patentee would however recommend the latter, not
only as it is cheaper, but, in his opinion, better than the
former. The bleached kind is made merely in compli¬
ance with the taste of some of his customers ; but he con¬
ceives the additional expense absolutely thrown away, as
the boiled is fully stronger, and, from the nature of its
preparation, in a short time becomes nearly as white.
Nor has it in any instance, more than the other, been
known to mildew.
Present Price of Dempster's Patent Camas,
Bleached, 2s, 8d.l . XT
Boiled, r 2s. Sd.jP61'^’^ L
The lighter kinds fall a halfpenny per ytyd on every
Number. 7
Cf Orders, addressed to the Patentee, will be attend
ed to, in regular succession, according to their dates,
St Andreips, Fifeshire,")
7th January, J809. j
D. IViflisw. Printer, Edinburgh.
V
P H O
[ 401 ]
P H O
Phocsea
Phlogifton owing to tlie important difcovery of tLe exigence of
heat in a ftate of compofition with other matter. Heat
, thus combined lofes its activity or becomes infenfible,
jutt in the fame way as any other active fubftance lofes
its apparent qualities in compofition. Acids, for ex¬
ample, when combined in a certain proportion with fub-
ilances for which they have ftrong attra&ion, as alkalies
or abforbent earths, lofe all their obvious acid qualities,
and the compound turns out mild, and totally conceals
the acid which it contains. In a fimilar manner, heat,
when combined in certain proportions with other mat¬
ter, lofes its fenfible qualities, and the compound con¬
ceals the heat which it contains. Heat, in this combin¬
ed ftate, was called by its ingenious difcoverer, Dr
Black, late7it heat, and it was found to be very abundant
in the atmofphere, which owes its exiftence as. an elaftic
fluid to the quantity of latent heat that it contains. Af¬
ter this difcovery was made, Dr Crawford, confidering
that air was abforbed by a burning body, concluded
that the heat which appears in the combuftion of a com-
buftible body, is the heat that had before exifted in the
air which was confumed by the burning body. M.
Lavoifier and others, profecuting this inquiry, found
that the combuftible body, while it is burning, unites
with the bafts of the air, and that the heat which the
air contained, and which was the caufe of the air exift-
ing in the ftate of air, is expelled. This abforption of
the bafts of the air by the burning body, and the reduc¬
tion of this bafts to a folid form, accounts for the in-
creafe of weight which a body acquires by burning j or,
in other words, gives a reafon why the matter into
which a combuftible body is converted by combuftion,
is heavier than the body from which it was produced.
The fame abforption of air is obfervable, when a metal
is converted into a calx, and the additional weight of the
calx is found to be precifely equal to the weight of the
air abforbed during the calcination. On thefe princi¬
ples, therefore, we now explain the phenomena in a
much more fatisfaftory manner than by the fuppofition
of phlogifton, or a principle of inflammability. See
Chemistry.
PHLOMIS, the Sage-tree, or Jerufalem Sage; a
genus of plants belonging to the didynamia clafs. See
Botany Index.
PHLOX, Lychnidea, or Baftard Lychnis; a genus
of plants belonging to the pentandria clafs. See Bota¬
ny Index.
PHLYCTENAE, in Medicine, fmall eruptions on
the Ikin.
PHOC A, a genus of quadrupeds of the order of ferae. .
See Mammalia Index.
PHOCyEA, the laft town of Ionia, (Mela, Pliny) ;
of yEolis, (Ptolemy), becaufe fttuated on the right cr
north fide of the river Hermus, which he makes the
boundary of iEolis to the fouth. It flood far in the
land, on a bay or arm of the feaj had two very fafe har¬
bours, the one called Lampter, the other Naujiathmos,
(Livy). It was a colony of lonians, fituated in the ter¬
ritory of yEolis, (Herodotus). Maflilia in Gaul was
again a colony from it. Phocceenfes, the people, (Livy) *,
Phocaicus, the epithet, (Lucan) 5 applied to Marfeilles.
It was one of the 1 2 cities which affembled in the pan¬
ionium or general council of Ionia.
Ancient Some writers tell us, that while the foundations of
vol! vi. city were hying, there appeared near the .{hare a
Vol. XVJ. Part II.
great ftioal of fea-calves; whence it was called Phoceca, Fliorrea
the word phoca fignifying in Greek a fea-calf. Ptole-—“v-—"
my, who makes the river Hermus the boundary be¬
tween yEolia and Ionia, places Phocaea in Atclis 5 but
all other geographers reckon it among the cities of Io¬
nia. It flood on the fea-coaft, between Cuma to the
north, and Smyrna to the foulh, not far from the Her¬
mus ; and was, in former times, one of the molt wealthy
and powerful cities of all Alia j but is notv a poor beg¬
garly village, though the fee of a bilhop. The Phocte-
ans were expert mariners, and the firft among the Greeks
that undertook long voyages} which they performed in
galleys of fifty oars. As they applied themfelves to
trade and navigation, they became acquainted pretty
early with the coafts and iflands of Europe, where they
are faid to have founded feveral cities, namely, Velia in
Italy ; Alalia, or rather Aleria, in Corlica ; and Mar¬
feilles in Gaul. Neither were they unacquainted with
Spain j for Herodotus tells us, that in the time of Cyr^s
the Great, the Phocaeans arriving at Sarteffus, a city m
the bay of Cadiz, were treated with extraordinary kind-
nefs by Arganthonius king of that country ; who, hear¬
ing that they were under no fmall apprehenfion of the
growing power of Cyrus, invited them to leave Ionia,
and fettle in what part of his kingdom they pleafed.
The Phocaeans could not be prevailed upon to for-
fake their country j but accepted a large fum of money,
which that prince generoufly prefented them with, to de¬
fray the expence of building a ftrong wall round their
city. The wall they built on their return j but it was
unable to refift the mighty power of Cyrus, whofe ge¬
neral Harpagus, invefting the city with a numerous ar¬
my, foon reduced it to the utmoft extremities. The
Phocaeans, having no hopes of any fuccour, offered to
capitulate j but the conditions offered by Harpagus
feeming fevere, they begged he would allow them three
days to deliberate j and in the mean time, withdraw his
forces. Harpagus, though not ignorant of their defign,
complied with their requeft. The Phocaeans, taking
advantage of this condefcenfion, put their wdves, chil¬
dren, and all their moft valuable eff'efts, on board feve¬
ral veffels wThich they had ready equipped, and convey¬
ed them fafe to the ifland of Chios, leaving the Perfians
in poffeflion of empty houles. Their defign was to pur-
chafe the Oeneftian iflands, which belonged to the
Chians, and fettle there. But the Chians not caring to
have them fo near, left they fliould engrofs all the trade
to themfelves, as they were a feafaring people, they put
to fea again ; and, having taken Phocaea, their native
country, by furprife, put all the Perfians they found in
it to the fword. They went to Corfica ; great part of
them however returned very foon, as did the reft alfo
in a fewr years. They then lived in fubjedlion either to
the Perfians, or tyrants of their own. Among the lat¬
ter we find mention made of Laodamus, who attended
Darius Hyftafpis in his expedition againft the Scythians;
and of Dionyfius, who, joining Ariftagoras, tyrant of
Miletus, and chief author of the Ionian rebellion, re¬
tired, alter the defeat of his countrymen, to Phoenicia,
vf'here he made an immenfe booty, feizing on all the
{hips he met with trading to that country. From Phoe¬
nicia he failed to Sicily, wrhere he committed great de¬
predations on the Carthaginians and Tufcans ; but is
faid never to have molefted the Greeks.
In the Roman times the city of Phocaea fided with
3 E Antiochus
HO [ 402 ] P H O
whereupon it was befieged, ta- Narfes, who then commanded the troops quartered on
Ancient
Uuiv. Hijl
voi. xv.
P
Antrochus the Great x
hen, and plundered, by the Roman general; but allow¬
ed to be governed by its own laws. In the war which
Atillonxns brother to Attains, king of Pergamus, raff¬
ed againfl the Romans, they aflifted the former to the
utmoll of their power 5 a circumftance which fo difpleaf-
ed the fenate, that they commanded the town to be de-
molilhed, and the whole race of the Phocseans to be ut¬
terly rooted out. This fevere lentence would have been
put in execution, had not the Maffilienfes, a Phocsean
colony, interpofed, and, with much difficulty, afluaged
the anger of the fenate. Pompey declared Phocaea a
free city, and reftored the inhabitants to all the privile¬
ges they had ever enjoyed; whence, under the firft em¬
perors, it was reckoned one of the moil flourilhing cities
of all Alia Minor. This is all we have been able to
collecl from the ancients touching the particular hiftory
of Phccaea.
PHOCAS, a Roman centurion, was raifed to the
dignity of emperor by the army, and was crowned at
Conftantinople about the year 603. The emperor
Mauritius, who w'as thus deferted both by the army
and the people, fled to Chalcedon with his five children,
whom Phocas caufed to be inhumanly murdered before
his eyes, and then he murdered Mauritius himfelf, his
brother, and feveral other perfons who were attached
to that family.
Phocas, thus proclaimed and acknowledged at Con¬
ftantinople, fent, according to cuftom, his own image
and that of his wife Leontia to Rome, where they were
received with loud acclamations, the people there being
incenfed againft Mauritius on account of the cruel exac¬
tions of the exarchs, and his other minifters in Italy.
Gregory, furnamed the Great, then bifhop of Rome,
icaufed the images to be lodged in the oratory of the
martyr Caefarius, and wrote letters to the new emperor,
congratulating him upon his advancement to the throne,
which he faid was effeded by a particular providence,
to deliver the people from the innumerable calamities
and heavy oppreffions under which they had long groan¬
ed. Had we no other character of Phocas and Leontia
but that which has been conveyed to us in Gregory’s
letters, we fnould rank him amongft the beft princes
mentioned in hiftory ; but all other writers paint him
in quite different colours; and his aftions, tranfmitted
to us by feveral hiftorians, evidently fpeak him a moft
cruel and blood-thirfty tyrant. He wTas of middling
ftature, fays Cedrenus, deformed, and of a terrible af-
pect : his hair w'as red, his eye-brows met, and one of
his cheeks was marked with a fear, which, when he
was in a paffion, grew black and frightful : he was
greatly addhfted to wane and women, blood-thirfty,
inexorable, bold in fpeech, a ftranger to compaffion,
in his principles a heretic. He endeavoured, in the
beginning of his reign, to gain the affe&ions of the
people by celebrating the Circenfian games with extra-
' ordinary pomp, and diftributing on that occafion large
fums among the people •, but finding that in (lead of
applauding they reviled him as a drunkard, he order¬
ed his guards to fall upon them. Some were killed,
many w7ounded, and great numbers were dragged to
prifon : but the populace rifing, fet them at liberty, and
thenceforth conceived an irreconcileable averfion to the
Plioeas
Phocion.
tyrant.
As foon
as the death of Mauritius was known,
the frontiers of Perfia, revolted. Phocas, however, ma¬
naged matters fo as to gain him over to his inlereft, and,
then treacheroufty and cruelly burnt him alive. He en¬
deavoured to ftrengthen his caufe by refpeftable allian¬
ces 5 but his cruelty was fuch as to render him generally
hated, for he fpared neither fex nor age, and amongft
others he murdered Conftantina the widow of Mauri¬
tius, and her daughters. Thefe cruelties were at
length the caufe of his downfall. He became uni-
verfally hateful 5 and perfons in great authority near his
perfon confphed againft him. This confpiracy, how¬
ever, was difeovered, and the perfons concerned in it
were all put to death. The following year, however,
61 o, he was overtaken by the fate he had fo long de-
ferved.
Heracli.us, the fon of the governor of Afi ica, who
bore the fame name, taking upon him the title of em¬
peror, and being acknowledged as fuch by the people of
Africa, failed from thence with a formidable fleet, and
a powerful army on "board, for Conftantinople, while
Nicetas marched thither by w?ay of Alexandria and the
Pentapolis, Heraclius fleered his courfe to Abydus,
wher'e he was received with great demonftrations of joy
by feveral perfons of rank, who had been baniflied by
Phocas. From Abydus he failed to Conftantinople,
where he engaged and utterly defeated the tyrant’s
fleet. Pliocas took refuge in the palace ; but one
Photinus, whofe wife he had formerly debauched, pur-
fuing him with a party of foldiers, forced the gates,
dragged the cowardly emperor from the throne, and
having ftripped him of the imperial robes, and clothed
him with a black veft, carried him in chains to Heracli¬
us, who commanded firft his hands and feet, then his
arms, and at laft his head, to be cut off: the remaining
part of his body was delivered up to the foldiers, who
burnt it in the forum. We are told, that Heraclius
having reproached him with his evil adminiftration, her
anfwered, with great calmnefs, “ It is incumbent upon
you to govern better.” Such wTas the end of this cruel
tyrant, after he had reigned feven years and fome
months.
PHOCILIDES, a Greek poet and philofopher of
Miletus, flouriftied about 540 years before the Chriftian
era. The poetical piece now extant, attributed to him,
is not of his compofition, but of another poet who lived
in the reign of Adrian.
PHOCION was. a diftinguiftied Athenian general
and orator in the time of Philip II. of Macedon. His
character is thus deferibed in the Ancient Univerfal
Hiftory. “ He was too modeft to felieit command, nor Ancient
did he promote wars that he might raife his authority by Univ- Hijl-
them 5 though, taken either as a foldier, orator, ftates-vo ’ v‘
man, or general, he was by far the moft eminent Athe¬
nian of his time. As he was a moft difinterefted patri¬
ot, he could entertain no great affedlion for Philip : but
as he perfeftly well knew the difpofition of his country¬
men, and howr unlikely they wrere long to fupport fuch
meafures as were neceffary to humble the Macedonian
power, he did not exprefs himfelf vehemently, but cbofe
rather to cultivate the efteem which on all occafions
Philip {bowed for the ftate of Athens, as a mean of
preferving her, when fhe fhould be reduced to that fitua-
tion which he conceived they wanted virtue to prevent.
From this chara&er the reader wall eafily difeern that
Demofthenes
PRO [ 403 1 PRO
Phocion. Demoftiienes and he could not well agree. The former
was always warm, his language copious, and his deligns
extenlive ) and Phocion, on the other hand, was of a
mild temper, delivered his opinion in very few words,
and propoled fchemes at once necelfavy and eai'y to be
effected. Yet he feldom or never concurred with the
people, but fpoke as poignantly againft their vices as
Demoffhenes himfelf; infomuch that this orator once
told him, ‘ The Athenians, Phocion, in fome of their
mad fits, will murder thee.’ ‘ The fame (anfwered he)
may fall to thee, Demofthenes, if ever they come to be
fober.”
He was afterwards appointed to command the army
which was lent to affiit the Byzantines againft Philip,
rshom he obliged to return to his own dominions.
This truly great man, whom (though extremely poor) no
fum could bribe to betray his country, and who at every
rilk on all occafions gave them found advice, was at
length acculed by his ungrateful countrymen. This
event happened in the year before Chrift 318. Pie
was fent to Athens by Polyperchon head of a faction in
Macedonia, together with his friends, chained in carts,
with this meflage, “ That though he was convinced
they were traitors, yet he left them to be judged by the
Athenians as a free people.” Phocion demanded whe¬
ther they intended to proceed againft him by form of
lawT; and fome crying out that they would, Phocion
demanded how that could be if they were not allowred
a fair hearing : but perceiving, by the clamour of the
people, that no fuch thing w’as to be expe&ed, he ex¬
claimed, “ As for myfelf, I confefs the crime objcdled
to me, and fubmit to the judgement of the law} but
confider, O ye Athenians, what have thefe poor inno-
- cent men done that they fhould be involved in the fame
calamity with me ?” The people replied with great
vociferation, “ They are your accomplices, and that is
enough.” Then the decree was read, adjudging them
all to death, viz. Phocion, Nicocles, Aheudippus, Aga-
mon, and Pythocles ^ thefe were prefent : Demetrius,
Phalereus, Callimedon, Charicles, and others, were con-
. demned in their abfence. Some moved that Phocion
might be tortured before he w’as put to death 5 nay,
they were for bringing the rack into the afiembly, and
torturing him there. The majority, however, thought
it enough if he wras put to death, for which the decree
wTas carried unanimoufiy ; fome putting on garlands of
flowers when they gave their votes. As he wras going
to execution, a perfon who wras his intimate friend afked
him if he had any meflage for his fon ? “ Yes,” re¬
plied Phocion *, “ tell him it is my laft command that
he forget how ill the Athenians treated his father.”
The fpleen of his enemies was not extinguifhed with
his life: they pa fled a decree whereby his corpfe was
bar.iihed the Athenian territories ; they likewife forbade
any Athenians to furnifli fire for his funeral pile. One
Conopian took up the corpfe, and carried it beyond
Eleufina, where he borrowed fome fire of a Megarian
woman and burned it. A Megaiian matron, who at¬
tended with her maid, raifed on the place an honorary
. monument; and having gathered up the bones, carried
them home, and buried them under her own hearth ;
praying at the fame time thus to the Penates : “ To
you, O ye gods, guardians of this place, I commit the
precious remains of the moft excellent Phocion. Pro-
tedf them, I befeech you, from all infults j and deliver
them one day to be repofiied in the fepulchre of his an- Phocion,
ceflors, when the Athenians (hall become wifer.” It, Phons. ^
was not long before this opportunity occurred. When "~"v
the Athenians began to cool a little, and remember the
many fervices they had received from Phocion, they de¬
creed him a ftatue of brafs ; ordered his bones to be
brought back at the public expence j and decreed that
his accufers ihould be put to death. Agnonides, who
wras principally concerned in that tragedy, fuffered j but
Epicurus and Demophilus, w’ho wrere alto accomplices
in it, fled. How’ever, Phocion’s fon met with them,
and executed his revenge upon them •, which w’as almoft
the only good action he ever performed, as he had a
very fmall Jffiare of his father’s abilities, and not any of
his virtues. Such is the ficklenefs and fuch the injuftice
of popular governments j failings which, if we are to
judge from univerfal experience, are abiblutely infepa-
rable from them.
PHOCIS, (Demofthenes, Strabo, Paufanias) j a
country of Greece, contained between Boeotia to the
ealt and Locris to the weft, but extending formerly
from the Sinus Corinthiacus on the fouth to the fea of
Euboea on the north, and, according to Dionyfius, as
far as Thermopylae j but reduced afterwards to narrower
bounds. Phocenfes, the people ) Phocicus, the epithet,
(Juftin) •, Bellurn Phocicum, the facred war which the
Thebans and Philip of Macedon carried on againft
them for plundering the temple at Delphi ; and by
which Philip paved the wray to the fovercignty of all
Greece, (Juflin.) Its greateft length w’as from north
to fouth, that is, from 38° 45' to 390 20', or about 35
miles; but very narrow’ from eaft to weft, not extending
to 30 miles, that is, from 230 io' to 230 40' at the wd-
deit, but about 23 miles towards the Corinthian bay,
and much narrower flill towards the north. This coun-^Y; Hl"
try is generally allowed to have taken its name from
Phocus the fon of Ornytion, a native of Corinth ; but
having been foon after invaded by the Eginetae, under
the conduct of another Phocus, who w’as the fon of Ea-
cus king of Enopia, the memory of the firft infenfibly
gave w ay to that of the fecond.
In Phocis there were many celebrated mountains,
fuch as Cythaeron, Helicon, and Parnassus. The
lait two we have already noticed in the order of the al¬
phabet. Cythaeron was confecrated to the mufes as
wrell as the other two. and was confequently much cele¬
brated by the poets. Both it and Plelicon contend with
Mount Parnaffus for height and magnitude. There were
no remarkable rivers in Phocis except Cephifus, which
runs from the foot of ParnaflTus northward, and empties
itfelf in the Pindus, w'hich was near the boundary of
that kingdom. It had feveral very confiderable cities •,
fuch as Cyrra, Criffa, and AntecyrA, which, accord¬
ing to Ptolemy, w’ere on the fea coafts ; and Pythia,
Delphi, Daulis, Elatia, Ergofthenia, and Baulia, which
were inland towns. Elatia w’as the largeft and richeft
after Delphi.
Deucalion was king of that part of Phocis w’hich lies
about Parnaifus, at the time that Cecrops llourifhed
in Attica ; but the, Phocians afterwards formed them-
felves into a commomvealth, to be governed by their ge¬
neral aflfemblies, the members of w’hich w’ere chofen
from among themfelves, and w’ere changed as often as
occafiou required. Of the hiftory of the Phocians but
little is known till the time of the holy war, of which
3 E 2 w;e
P H O r 404 ] P H O
Piiocis we have the following account in the Ancient Univer-
Pk M . . fal Hiftory.
i oe^nicia-i « The Phocians having prefumed to plough the terri¬
tories of the city of Gyrra, cohfecrated to the Delphic
god, were fummoned by the other Grecian dates before
the court of the Amphidtyons, where a conhderable fine
was impofed upon them for their facrilege. They re-
fufed to pay it, on pretence that it was too large $ and
at the next aflembly their dominions were adjudged con-
fifcated to the ufe of the temple. This fecond fentence
exafperated the Phocians dill more 5 who, at the indi-
gation of one Philomelus, or, as he is called by Plu¬
tarch, Philomedes, feized upon the temple, plundered it
of its treafure, and held the facred depofitum for a con-
fiderable time. This fecond crime occafioned another
' affembly of the Amphi&yons, the refult of which was
a formal declaration of war againd the Phocians. The
quarrel being become more general, the feveral dates
took part in it according to their inclinations or intered.
Athens, Sparta, and fome others of the Peloponnefians,
declared for the Phocians j and the Thebans, Theffali-
ans, Locrians, and other neighbouring dates, againd
them. A war was commenced with great fury on both
lides, and dyled the holy war, which laded ten years j
during which the Phocians, having hired a number of
foreign troops, made an obdinate defence, and would in
all probability have held out much longer had not Phi¬
lip of Macedon given the finidiing droke to their total
defeat and punidunent. The war being ended, the
grand council affembled again, and impofed an annual
fine of 60 talents upon the Phocians, to be paid to the
temple, and continued till they had fully repaired the
damage it had fudained from them ; and, till this repa¬
ration fhould be made, they were excluded from dwell-
’ ing in walled towns, and from having any vote in the
grand affembly. They did not, however, continue long
under this heavy fentence : their known bravery made
their adidance fo neceffary to the reft, that they were
glad to remit it ; after which remiflion they continued
to behave with their ufual courage and refolution, and
foon obliterated their former guilt.”
We cannot finifh this article without mentioning
more particularly Daulis, rendered famous, not fo much
for its extent or richnefs, as for the dature and prowefs
of its inhabitants ; but dill more for the inhuman repad
which was ferved up to Tereus king of Thrace by the
women of this city, by whom he was foon after murder¬
ed for the double injury he had done to his fider-in-law
Philomela, daughter of Pandion king of Athens. See
Philomela. *
JPHOEBUS, one of the names given by ancient my-
thologids to the Sun, Sol, or Apollo. See Apollo.
PHOENICIA, or more properly Phoenice, the an¬
cient name of a country lying between the 34th and
36th degrees of north latitude j bounded by Syria on Phoenicia,
the north and ead, by Judcea on the fouth, and by the ' v- 1
Mediterranean on the weft. Whence it borrowred its
name is not abfolutely certain. Some derive it from jnc;ent
one Phoenix 5 others from the Greek word phoenix, fig- Univ. Hijt.
nifying a palm or date, as that tree remarkably abound- vol. ii.
ed in this country. Some again fuppofe that Phoenice
is originally a tranilation of the Hebrew word Edom,
from the Edomites who fied thither in the days of Da¬
vid. By the contraction of Canaan it was alfo called
Chna, and anciently Rhabbothin and Colpitis (a). The
Jews commonly named it Canaan ; though fome part of
it, at lead, they knew by the name of Syrophcenice (b).
Bochart tells us that the mod probable etymology is
Phene Anak, i. e. “ the defendants of Anak.” Such
were the names peculiar to this fmall country j though
Phoenice was fometimes extended to all the maritime
countries of Syria and Judea, and Canaan to the Phili-
ftines, and even to the Amalejsites. On the contrary,
thefe two names, and the reft, wTere mod generally fwal-
lowed up by thofe of Paleftine and Syria (c).
There is fome difagreement among authors with re-
fpeft to the northern limits of this country. Ptolemy
makes the river Eleutherus the boundary of Phoenice
to the north ■, but Pliny, Mela, and Stephanus, place it
in the ifland of Aradus, lying north of that river.
Strabo obferves, that fome will have the river Eleuthe¬
rus to be the boundary of Seleucis, on the fide of Phoe¬
nice and Ccelefyria. On the coaft of Phoenice, and
fouth of the river Eleutherus, ftood the following cities :
Simyra, Orthofia, Tripolis, Botrys, Byblus, Palaeby-
blus, Berytus, Sidon, Sarepta, Tyrus, Palsetyrus.
Phoenice extended, according to Ptolemy, even be¬
yond Mount Carmel *, for that geographer places in
Phoenice not only Ecdippa and Ptolemais, but Sycami-
num and Daera, which ftand fouth of that mountain.
Thefe, however, properly fpeaking, belonged to Pale¬
ftine. We wall not take upon us to mark out the
bounds of the midland Phoenice. Ptolemy reckons in
it the following towns $ Area, Paige byblus (Old Byb¬
lus), Gabala, and Caefaria Paniae. This province was
confiderably extended in the times of Chriftianity j
when, being confidered as a province of Syria, it inclu¬
ded not only Damafcus but Palmyra alfo.
The foil of this country is good, and productive of
many neceffaries for food and clothing. The air is
wholefome, and the climate agreeable. It is plentifully
watered by fmall rivers} which, running down from
Mount Libanus, fometimes fwell to an immoderate de¬
gree, either increafed by the melting of the fnows on
that mountain, or by heavy rains. Upon thefe occa-
fions they overdow, to the great danger and hinderance.
of the traveller and damage of the country. Among
thefe rivers is that of Ai>onis.
It
(a) This lad name is a tranflation of the firft. Rabhotfen is in Hebrew, a great gulf or bay. From rabhotfen,
by changing the Hebrew tf into the Greek t, comes rabboten ; and, with a little variation, rhabbothin. KeAiros,
colpos, is Greek alfo for a bay or gulf; whence it appears that colpitis or colpites is a tranflation of rabbothin.
(b) Bochart fuppofes that the borderers, both upon the Phoenician and Syrian fide, were called by the common-
name of Syrophcenicians, as partaking equally of both nations.
(c) Or rather Phcenice, Paleftine, and Syria, were promifeuoufly ufed for each other, and particularly the two
former. Phoenice and Paleftine, fays Stephanus Byzantinus, were the fame. As for Syria, we have already obfer-
ved, that in its larged extent it fometimes comprehended Phoenice and Coelefyria. Herodotus plainly confounds
thfffe three names) we mean, ufes one for the other indifferently.
P H O
[ 405 ]
P H 0
»• It is univerfally allowed that the Phoenicians were
Canaanites (d) by defcent: nothing is plainer or lefs
contefted, and therefore it were time loft to prove it.
We flrall only add, that their blood muft have been
mixed with that of foreigners in procefs of time, as it
happens in all trading’ places •, and that many ftrange
families muft have fettled among them, who could
confequently lay no claim to this remote origin, how
much foever they may have been called Phoenicians,
and reckoned of the fame defcent with the ancient
proprietors.
The Phoenicians were governed by kings j and their
territory, as fmall a Hip as it was, included feveral king¬
doms j namely, thofe of Sidon, Tyre, Aradus, Berytus,
and Byblus. In this particular they imitated and ad¬
hered to the primitive government of their forefathers j
who, like the other Canaanites, were under many petty
princes, to whom they allowed the fovereign dignity,
referving to themfelves the natural rights and liberties
of mankind. Of their civil laws we have no particu¬
lar fyftem.
With regard to religion, the Phoenicians wrere the
moft grofs and abominable idolaters. The Baal-berith,
Baalzebub, Baalfamen, &c. mentioned in Scripture,
were fome of the Phoenician gods j as were alfo the
Moloch, Aftitaroth, and Thammuz, mentioned in the
facred writings.—The word Baa/, in ilfelf an appella¬
tive, was no doubt applied to the true God, until he
rejected it on account of its being fo much profaned by
the idolaters. The name was not appropriated to any
particular deity among the idolatrous nations, but was
common to many ; however, it was generally imagined
that one great God preftded over all the reft. Among
the Phoenicians this deity was named Baal-famen ; whom
the Hebrews would have called BaalJhemim, or the
God of heaven. In ail probability this was alfo the
principal Carthaginian deity, though his Punic name is
unknown. We have many religious rites of the Car¬
thaginians handed down to us by the Greek and Roman
writers j but they all beftowed names of their own gods
upon thofe of the Carthaginians, which leads us to a
knowledge of the correfpondence between the charafters
of the Phoenician and European deities. The principal
deity of Carthage, according to Diodorus Siculus, was
Chronus or Saturn. The facrifices offered up to him
were children of the beft families. Our author alfo tells
us, that the Carthaginians had a brazen ftatue or colof-
fus of this god, the hands of which were extended in
a61 to receive, and bent downwards in fuch a manner,
that the child laid thereon immediately fell down into
a hollow where there was a fiery furnace. He .adds
alfo, that this- inhuman pradfice feemed to confirm a
tradition, handed down to the Greeks from very ear¬
ly antiquity, viz. that Saturn devoured his own chil¬
dren.
The goddefs Cceleftis, or Urania, was held in the
higheft veneration by the Carthaginians. She is Phoerie a,
thought to have been the fame with the queen of hea- » _
ven mentioned in Jeremiah, the Juno Olympia of the
Greeks. According to Hefychius, the fame word ap¬
plied in the Punic language both to Juno and Venus:
Nay, the ancient Greeks frequently confound Juno,
Venus, and Diana or the moon, all together 5 which is
to be attributed to the Egyptians and Phoenicians, from
whom they received their i’yftem of religion 5 wTho feem
in the moft ancient times to have had but one name for
them all. Befides thefe there were feveral other deities
of later date, who were worfliipped among the Phoeni¬
cians, particularly thofe of Tyre, and confequently
among the Carthaginians alfo. Thefe were Jupiter,
Apollo, Mars, and Bacchus. Jupiter was worftiipped
under the name of Belus or Baal. To him they addref-
fed their oaths •, and placed him for the moft part, as
there is reafon to believe, at the head of their treaties.
The fame name was alfo given to the other two, whence
they were frequently miftaken for one another. Apollo
or the fun, -went either by this name limply, or by others,
of which this made a part.
The Carthaginian fuperftition, however, was not con¬
fined to thefe deities alone. They worthipped alio the
fire, air, and other elements; and had gods of rivers,
meads, &c. Nay, they paid divine honours to the fpi-
rits of their heroes, and even to men and women them¬
felves while yet in life ; and in this adoration Hannibal
the Great had for fome time a ihare, notwithftanding
the infamous condu6l of his countrymen towards him
at laft. In order to worlhip thole gods with more con-
vemency on all occafions, the Carthaginians had a kind
of portable temples. Thefe were only covered chariots,
in which were fome fmall images reprefenting their fa¬
vourite deities; and which were drawn by oxen. They
were alfo a kind of oracle ; and their refponfes were un-
derftood by the motion impreffed upon the vehicle.
This was likewife an Egyptian or Libyan cuftom 3 and
Tacitus informs us that the ancient Germans had fome-
thing of the fame kind. The tabernacle of Moloch is
thought to have been a machine of this kind 3 and it is
not improbable that the whole was derived from the ta¬
bernacle of the Jews in the wildernels.
Befides all the deities above-mentioned, we ftill find
another, named the Daemon or Genius of Carthage,
mentioned in the treaty made by Philip of Macedon
and Hannibal. What this deity might be, we know
not 3 however, it may be obferved, that the pagan world
in general believed in the exiftence of demons, or intel¬
ligences who had a kind of middle nature between gods
and men, and to whom the adminiftration of the world
was in a great meafure committed. Hence it is na
wonder that they fttould have received religious honours.
For when once mankind were poffeffed with the opinion
that they were the minillers of the gods, and trufted
with the difpenfation of their favours, as well as the in-
flidlion
(d) Bochart infinuates that the Canaanites were afiiamed of their name, on account of the curfe denounced on
their progenitor, and terrified by the wars fo vigoroufiy and fuccefsfully waged on them by the Ifraelites, purely be-
eaufe they were Canaanites 3 and that therefore, to avpid the ignominy of the one and the danger of the other, ,
they abjured their old name, and changed it for Phoenicians, Syrians, Syrophoenicians, and Affyrians. Heideuger
conje6tures alfo that they were afhamed of their ancefter Canaan.
P H O
fliclion of tlieir punifliments, it is natural to fuppofe that
they would be defirous of making their addreffes to
them. See Astarte and Polytheism.
Herodotus iuppoies the Phoenicians to have been cir-
cumcifed j but Jofephus aiTerts, that none of the nations
included under the vague name of Paleftine and Syria
ufed that rite, the Jews excepted ; fo that if the Phoe¬
nicians had apciently that cuftom, they came in time to
negleft it, and at length wholly laid it alkie. They
abltained however from the flelh of (wipe.
Much is faid of their arts, fciences, and manufactures;
but as what we find concerning them is couched in ge¬
neral terms only, rve cannot defcant on particulars.
The Sidonians, under which denomination we compre¬
hend the Phoenicians in general, were of a molt happy
genius. They were from the beginning addifted to
philofophical exercifes of the mind 5 infomuch that a
Sidonian, by name Mofchus, taught the doCtrine of
atoms before the Trojan wTar : and Abomenus of Tyre
puzzled Solomon by the fubtilty of his queftions.
Phoenice continued to be one of the feats of learning,
and both Tyre and Sidon produced their philofophers
of later ages ; namely, Boethus and Diodatus of Sidon,
Antipater of Tyre, and Appollonius of the fame place;
who gave an account of the writings and difciples of
Zeno. For their language, fee Philology, n° 61.
As to their manufa&ures, the glafs of Sidon, the purple
of Tyre, and the exceeding fine linen they wove, were
the produCt of their cuvn country, and their own in¬
vention : and for their extraordinary fkill in working
metals, in hewing timber and Hone ; in a word, for
their perfeCt knowledge .of what was folid, great, and
ornamental in architecture—we need only put the read¬
er in mind of the large lhare they had in erecting and
decorating the temple at Jerufalem under their king
Hiram. Their fame for tafte, ,defign, and ingenious
invention, was Inch, that whatever was elegant, great,
or pleafing, whether in apparel, veffels, or toys, was
diitinguilhed by way of excellence with the epithet of
Sidonian.
The Phoenicians were likewife celebrated merchants,
navigators, and planters of colonies in foreign parts. As
merchants, they may be faid to have engroffed all the
commerce of the weftern world : as navigators, they
were the boldeft, the moft experienced, and greateft dif-
coverers, of the ancient times : they had for many ages
no rivals. In planting colonies they exerted themfelves
fo much, that, confidering their habitation was little
more than the flip of ground between Mount Libanus
and the fea, it is furprifing how they could furnifli fuch
fupplies of people,- and not wholly depopulate their na¬
tive country.
It is generally fuppofed that the Phoenicians were in¬
duced to deal in foreign commodities by their neigh¬
bourhood with the Syrians, who were perhaps the
mofl: ancient of thofe who carried on a conflderahle
and regular trade with the more eaftcrn regions: and
this conjeChire appears probable at leaft; for their
owm territory was but fmall, and little able to afford
any confiderable exports, if we except manufactures :
but that their manufactures were anyways confiderable
till they began to turn all the channels of trade into their
own country, it is hard to believe. In Syria, which was 1
a large country, they found ftore of productions of the
natural growth of that foil, and many choice and uf'e-
2
406 ] P H O
ful commodiles brought from the eaft. Thus, having Phoenicia.
a kite coail, with convenient harbours, on one fide, and ~—'» ^
excellent materials for {hip-building on the other; per¬
ceiving how acceptable many commodities that Syria
furnifiled would be in foreign parts, and being at the
fame lime, perhaps, fhown the w ay by the Syrians them¬
felves, who may have navigated the Mediterranean—■
they turned all their thoughts to trade and navigation,
and by an uncommon application foon eclipfed their
fters in that art.
It were in vain to talk of the Edomites, who fled hi¬
ther in David’s time ; or to inquire why Herodotus fup-
pofes the Phoenicians came from the Red fea ; their ori¬
gin we have already feen. That feme of the Edomites
fled into this country in the days of David, and that
they were a trading people, is very evident: what im¬
provements they brought with them into Phoenice,- it is
hard to fay ; and by the wTay, it is as difficult to afeertain
their numbers. In all probability they brought with
them a knowdedge of the Red fea, and of the fouth parts
of Arabia, Egypt, and Ethiopia; and by their informa¬
tion made the Phoenicians acquainted with thofe coalfs ;
by which means they were enabled to undertake voy¬
ages to thofe parts, for Solomon, and Pharoah Nee ho,
king of Egypt.
Their whole thoughts were employed on fchemes to
advance their commerce. They affe&ed no empire but
that of the fea; and feemed to aim at nothing but the
peaceable enjoyment of their trade. This they extend¬
ed to all the known parts they could reach ; to the
Britifti ifles, commonly under-flood by the Caffiterides ;
to Spain, and other places in the ocean, both within
and without the ftraits of Gibraltar; and, in gene¬
ral, to all the ports of the Mediterranean, the Black
fea, and the lake Maeotis. In all theie parts they had
fettlements and correlpondents, from winch they drew
what was ufeful to themfelves, or might be fo to others';
and thus they exercifed the three great, branches of
trade, as it is commonly divided into importation, expor¬
tation, and tranfportation, in full latitude. Such was
their fea-trade ; and for that w hich they carried on by
land in Syria, Mefopotamia, Affyria, Babylonia, Pcr-
fla, Arabia, and even in India, it was of no lefs extent,
and may give us an idea of what this people once was,
how rich and how defcrvedly their merchants are men¬
tioned in Scripture as equal to princes. Their coun¬
try was, at that time, the great wareheule, where every
thing that might either adminifter to the neceflities or
luxury of mankind was to be found ; which' they diilri-
buted as they judged would be the heft for their own
intereft. The purple of Tyre, the glafs of Sidon, and
the exceeding fine linen made in this country, together
with other curious pieces of art in metals and w>ood, al¬
ready mentioned, appear to have been the chief and al-
mofl only commodities of Phoenice itfelf. Indeed their
territory was fo final!, that it is not to be imagined they
could afford to export any of their own growth ; it is
more likely that they rather wanted than abounded with
the fruits of the earth.
Having thus fpoken in general terms of their trade,
we fhall now touch upon their {hipping and forne things
remarkable in their navigation. Their larger embar-
lations were of two forts ; they divided them into round
fliips or gauli; and long flops, galleys, or triremes.
When they drew7 up in line of battle, the gauli were dif-
pofed
P H O [ 407 ] P H O
Phoemrop. pofed at a fmall diftance from each other in the wings,
teruS or in the van and the rear : their triremes were con-
^ Phopiyx. ^ tra(^e(j together in the centre. If, at any time, they
obferved that a ftranger kept them company in their
voyage, or followed in their track, they were Hire to get
rid of him if they could, or deceive him if pofiible 5 in
which policy they went fo far, as to venture the lofs of
their ihips, and even their lives; fo jealous ivere they of
foreigners, and fo fcenacioufly bent on keeping the whole
trade to themfelves. In order to difcourage other na¬
tions from engaging in commerce, they praftifed pi¬
racy, or pretended to be at war with fuch as they met
when they thought themfelves ftrongett. This was but
a natural ftroke of policy in people who grafped at the
whole commerce of the then known world. We mull
not forget here the famous fifhery of Tyre, which fo re¬
markably enriched that eiiy. See Astronomy, n°« 7.
Ophir, and Tyre.
PHOENICQPTERUS, or Flamingo, a genus of
bird? belonging to the order of grallce. See Ornitho¬
logy Index.
PHOENIX, in AJlronomy. See Astronomy Index.
Phoenix, the Great Palm, or Date tree, a genus of
plants belonging to the order of palmae. See Botany
Index. As the account of this valuable plant already
given in its proper place, under Botany', is rather ihort
to be fatisfaflory, we lhall here enter a little more into
the detail of its natural hiftory. There is only one
fpecies, viz. the daclylifera, or common date-tree, a na¬
tive of Africa and eaftern countries, where it grows to ;o,
60, and 100 feet high. The trunk is round, upright,
and iiudded with protuberances, which are the veftiges
of the decayed leaves. From the top iiTucs forth a
clufter of leaves or branches eight or nine feet long, ex¬
tending all around like an umbrella, and bending a lit¬
tle towards the earth. The bottom part produces a
number of ftalks like thole of the middle, but feldom
{hooting fo high as four or five feet. Thefe ftalks, fays
Adanfon, diffule the tree very confiderably ; fo that,
wherever it naturally grows in forefts, it is extremely
difficult to open a paffage through its prickly leaves.
The date-tree was introduced into Jamaica foon after
the conqueft of the ifland by the Spaniards. There are
however, but few of them in Jamaica at this time. The
fruit is fomewhat in the fhape of an acorn. It is com-
pofed of a thin, light, and glofly membrane, fomewhat
pellucid and yellowiffi ; which contains a fine, foft, and
pulpy fruit, which is firm, fweet, and fomewhat vinous
to the tafte, efculent, and wholefome; and within this
is inclofed a folid, tough, and hard kernel, of a pale grey
colour on the outfide, and finely marbled within like the
nutmeg. For medicinal ufe dates are to be chofen large,
full, frefli, yellow on the furface, foft and tender, not
too much wrinkled; fuch as have a vinous tafte, and
do not rattle when ftiaken. They are produced in
many parts of Europe, but never ripen perfeftly there.
The bell are brought from Tunis; they are alfo very
fine and good in Egypt and in many parts of the eaft.
Thofe of Spain and France look well; but are never
perfectly ripe, and very fubject to decay. They are
prei'erved three different ways ; feme preffed and dry ;
others preffed more moderately, and again moiftened
with their own juice ; and- others not preffed at all, but
moiftened with the juice of other dates, as they are
packed up, which is done in balkets or {kins. Thofe
preferved in this laft way are much the beft. Dates Phoenix,
have always been efteemed moderately ftrengthening and —w"-
aftringent.
Though the date tree grows everywhere indiferimi-
nately on the northern coafts of Africa, it is not cul¬
tivated with care, except beyond Mount Atlas; be-
caufe the heat is not fufficiently powerful along the
coafts to bring the fruits to proper maturity. We ffiall
here extradl iome obfervations from Mr l)es Fontaines
relpedting the manner of cultivating it in Barbary,
and on the different ufes to which it is applied. All
that part of the Zaara which is near Mount Atlas,
and the only part of this vaft defert wTh:ch is inhabi¬
ted, produces very little corn ; the foil being fandy,
and burnt up by the fun, is almoft entirely unfit for
the cultivation of grain, its only produftions of that
kind being a little barley, maize, and forgo. The
date-tree, however, fupplies the deficiency of corn to
the inhabitants of thefe countries* and furniffics them
with almoft the whole of their fubfiftence. They have
fiocks of {beep ; but as they are not numerous, they
preferve them for the fake of their wool; beiides, the
llefti of thefe animals is very unwholefome food in
countries that are exceffively warm ; and thefe people,
though ignorant, have probably been enabled by ex¬
perience to know that it was falutary for them to ab-
ftain irom it. The date trees are planted without any
order, at the diftance of 12 feet one from the other,
in the neighbourhood of rivulets and ftreams which
iflue from the land. Forens of them may be feen here
and there, fome of which are feveral leagues in cir¬
cumference. The extent of thefe plantations depends
upon the quantity of water which can be procured to
water them: for they require much moiiture. All
thefe forefts are intermixed with orange, almond, and
pomegranate trees, and with vines which twift round
the trunks of the date trees; and the heat is ftrong
enough to ripen the fruit, though they are never ex poled
to the fun.
Along the rivulets and ftreams, dykes are eredfted
to ftop the courfe of their waters, in order that they
may be diftributed amongft the date trees by means of
fmall canals. The number of canals is fixed for each
individual ; and in feveral cantons, to have a right to
them, the proprietors are obliged to pay an annual fum
proportionable to the number and extent of their planta¬
tions. Care is taken to till the earth well, and to raife
a circular border around the root of each tree, that the
water may remain longer and in larger quantity. The
date trees are watered in every feafon, but more particu¬
larly during the great heats of fummer.
It is generally in winter that new plantations of this
tree are formed. For this purpofe thofe who cultivate
them take {hoots of thofe which produce the beft dates,
and plant them at a fmall diftance one from the other.
At the end of three or four years thefe {hoots, if they
have been properly taken care of, begin to bear fruit;
but this fruit is as yet dry, without fweetnefs, and even
without kernels ; they never reach the higheft degree of
perfection of which they are fufceptible till they are
about 15 or 20 years old.
Thefe plants are however produced from the leeds ta¬
ken out of the fruit, provided they are freffi. They
ftiould be fown in pots filled wfith light rich earth, and
plunged into a moderate hotbed of tanners bark, which.
ftiould
/
P H O [40
Phoenix, {liould be kept in a moderate temperature of heat, and
^ the earth frequently refrelhed with water. When the
plants are come up to a proper fize, they (hould be each
planted in a feparate fmall pot, filled with the fame
light earth, and plunged into a hotbed again, obferving
to refrelh them with water, aS alfo to let them have air
in proportion to the warmth of the feafon and the bed
in which they are placed. During the fummer time
they Ihould remain in the fame hotbed } but in the be¬
ginning of Auguft, they Ihould have a great lhare of
air to harden them againlt the approach of winter ; for
if they are too much forced, they will be fo tender as
not to be preferved through the wunter without much
difficulty, efpecially if you have not the conveniency of
a bark dove to keep them in. The foil in which thefe
plants ffiould be placed, mult be compofed in the fol-
« lowing manner, viz. half of light freffi earth taken from
a patture-ground, the other half fea fand and rotten
dung or tanners bark in equal proportion ; thefe ffiould
be carefully mixed, and laid in a heap three or four
months at lead before it is ufed, but ffiould be often
turned over to prevent the growth of weeds, and to
fweeten the earth.
The trees, however, which fpring from feed never
produce fo good dates as thofe that are raifed from
ffioots •, they being always poor and ill taded. It is un¬
doubtedly by force of cultivation, and after feveral ge¬
nerations, that they acquire a good quality.
The date trees which have been originally fown, grow
rapidly, and we have been aiTured that they bear fruit
in the fourth or fifth year. Care is taken to cut the in¬
ferior branches of the date tree in proportion as they
rife and a piece of the root is always left of fome inches
in length, which-affords the eafy means of climbing to
the fummit. Thefe trees live a long time, according to
the account of the Arabs and in order to prove it,
they fay that when they have attained to their full
growth, no change is obferved in them for the fpace of
' three generations.
The number of females which are cultivated is much
fuperior to that of the males, becaufe they are much
more profitable. The fexual organs of, the date tree
grow, as is well known, upon different dalks, and thefe
trees dower in the months of April and May, at which
time the Arabs cut the male branches to impregnate the
female. For this purpofe, they make an incifion in the
trunk of each branch which they wiffi to produce fruit,
and place in it a dalk of male dowers 5 without this pre¬
caution the date tree would produce only abortive
fruit (a). In fome cantons the male branches are only
Ihaken over the female. The praftice of impregnating
the date tree in this manner is very ancient. Pliny de-
8 ] P H O
fcribes it very accurately in that part of his work where
he treats of the palm tree.
There is fcarcely any part of the date tree which is
not ufeful. The wood, though' of a fpongy texture,
lads fuch a number of years, that the inhabitants of the
country fay it is incorruptible. They employ it for mak¬
ing beams and indruments of huffiandry j it burns dow-
ly, but the coals which refult from its combudion are
very drong, and produce a great heat.
The Arabs drip the bark and fibrous parts from the
young date trees, and eat the fubdance which is in the
centre ; it is very nouriffiing, and has a fweet tade : it
is known by the name of the marrow of the date tree.
They eat alfo the leaves, when they are young and ten¬
der, with lemon juice 5 the old ones are laid out to dry,
and are employed for making mats and other works of
the fame kind, wffiich are much ufed, and with wffiich
they carry on a confiderable trade in the interior parts of
the country. From the fides of the dumps of the
branches which have been left arife a great number of
delicate filaments, of wffiich they make ropes, and which
might ferve to fabricate cloth.
Of the fredi dates and fugar, fays Haffelquid, the
Egyptians make a conferve, which has a very pleafant
tade. In Egypt they ufe the leaves as fiy-fiaps, for
driving away the numerous infedls wffiich prove fo
troublefome in hot countries. The hard boughs are
ufed for fences and other purpofes of huffiandry 5 the
principal dem for building. The fruit, before it is
ripe, is fomewffiat adringent 5 but when thoroughly
mature, is of the nature of the fig. The Senegal
dates are ffiorter than thofe of Egypt, but much thick¬
er in the pulp, which is faid to have a fugary agree¬
able tade, fuperior to that of the bed dates of the Le¬
vant.
A wffiite liquor, known by the name of v/z’/£, is drawm
alfo from the date tree. To obtain it, all the branches
are cut from the fummit of one of thefe trees, and after
feveral incifions have been made in it, they are covered
with leaves, in order that the heat of the fun may not
dry it.
The fap drops dowm into a veffel placed to receive
it, at the bottom of a circular groove, made below the
incifions. The1'mi Ik of the date tree has a fweet and
agreeable tade wffien it is new •, it is very refrediing, and
it is even given to fick people to drink, but it generally
turns four at the end of 24 hours. Old trees are chofen
for this operation, becaufe the cutting of the branch¬
es, and the large quantity of fap wffiich dows from
them, greatly exhaud then*, and often caufe them to de¬
cay.
The male flowers of the date tree are alfo ufeful.
They
Phoeri.r.
(a) The celebrated Linnaeus, in his Differtation on the Sexes of Plants, fpeaking of the date tree, fays, “ A
female date-bearing palm flowered many years at Berlin without producing any feeds j but the Berlin people taking
care to have fome of the bloffoms of the male tree, which was then flow'ering at Leipfic, fent to them by the pod,
they obtained fruit by thefe means j and fome dates, the offspring of this impregnation, being planted in my gar¬
den, fprung up, and to this day continue to grow vigoroufly. Koempfer formerly told us, how necefl'ary it w^as
found by the oriental people, who live upon the produce of palm trees, and are the true Lotoplwgi, to plant fome
male trees among the females, if they hoped for any fruit: hence it is the praftice of thofe w ho make w ar in that
part of the world to cut dowm all the male palms, that a famine may afflilt their proprietors j fometimes even the
inhabitants themfelves deflroy the male trees when they dread an invafion, that their enemies may find no fufle-
Itance in the country.”
\
4
P H O [ 409 ] P H 0
P'hocnix. They are eaten when ftill tender, mixed up with a little
*’ v T lemon iuice. They are reckoned to be very provoca¬
tive : the odour which they exhale is probably the caul’e
of this property being afcribed to them.
Thefe date trees are very lucrative to the inhabi¬
tants of the defert. Some of them produce 20 bunches
of dates ; but care is always taken to lop off a part
of them, that thofe which remain may become larger j
10 or 12 bunches only are left on the moft vigorous
trees.
It is reckoned that a good tree produces, one year
with another, about the value of 10 or 12 (hillings to
the proprietor. A pretty confiderabie trade is carried
On with dates in the interior part of the country, and
large quantities of them are exported to France and Ita¬
ly. The crop is gathered towards the end of Novem¬
ber. When the bunches are taken from the tree, they
are hung up in fome very dry place where they may be
(heltered and fecure from infefts.
Dates afford wholefome nourifhment, and have a very
agreeable tafte when they are frdh. The Arabs eat
them without feafoning. They dry and harden them in
the fun, to reduce them to a kind of meal, which they
lay up in ftor-e to fupply themfelves with food during
the long journeys which they often undertake acrofs their
deferts. This limple food is fufficient to nourilh them
for a long time.—-The inhabitants of the Zaara procure
alfo from their dates a kind of honey which is exceed¬
ingly fweet. For this purpofe they choofe thofe which
have the fofteft pulp ; and having put them into a
large jar with a hole in the bottom, they fqueeze them
by placing over them a weight of eight or ten pounds.
—The iroft fluid part of the fubftance, which drops
through the hole, is what they call the honey of the
date.
Even the ftones, though very hard, are not thrown
away. They give them to their camels and fheep as
food, after they have bruifed them or laid them to foften
in water.
The date, as well as other trees which are cultivated,
exhibits great variety in its fruit, with refpecf to ffiape,
fize, quality, and even colour. There are reckoned to
be at leaft twenty different kinds. Dates are very liable
to be pierced by rvorms, and they foon corrupt in moift
or rainy weather.
From what has been faid, it may eafily be perceived,
that there is, perhaps, no tree whatever ufed for fo ma¬
ny and fo valuable purpofes as the date tree.
Thoenix, in antiquity, a famous bird, which is ge¬
nerally looked upon by the moderns as fabulous. The
ancients fpeak of this bird as fingle, or the only ono of
its kind ; they defcribe it as of the fize of an eagle; its
head finely crefted with a beautiful plumage, its neck
covered with feathers of a gold colour, and the reft of
its body purple, only the tail white, and the eyes fpark-
ling like ftars: they hold, that it lives 560 or 600
years in the wildernefs •, that when thus advanced in
age, it builds itfelf a pile of fweet wood and aromatic
gums, and fires it with the wafting of its wings, and
thus burns itfelf; and that from its afhes arifes a worm,
which in time grows up to be a phoenix. Hence the
Phoenicians gave the name of phoenix to the palm-tree ;
becaufe when burnt down to the root it rifes again fairer
than ever.
In the fixth book of the Annals of Tacitus, fe<5t. 28.
Vol. XVI. Part II.
it is obferved that, in the year of Rome 787, the phoe¬
nix reviiited Egypt 5 which occafioned among the learn¬
ed much fpeculation. This being is facred to the fun.
Of its longevity the accounts are various. The common
perfuafion is, as we have mentioned above, that it lives
500 years j though by fome the date is extended to
1461. The feveral eras when the phoenix has been feen
are fixed by tradition. The firft, we are told, was in
the reign of Sefoftris ; the fecond in that of Amafis 5
and, in the period when Ptolemy the third of the Ma¬
cedonian race was feated on the throne of Egypt, an¬
other phoenix dire&ed its flight towards Heliopolis.
When to thefe circumftances are added the brilliant ap¬
pearance of the phoenix, and the tale that it makes fre¬
quent excurfions with a load on its back, and that when,
by having made the experiment through a long trad! of
air, it gains fufficient confidence in its own vigour, it
takes up the body of its father and flies with it to
the altar of the fun to be there confumed ; it cannot
but appear probable, that the learned of Egypt had
enveloped under this allegory the philofophy of co¬
mets.
Phoenix, fon of Amyntor king. oi^Vrgos by Cleo-
bule or Hippodamia, was preceptor to young Achilles.
His father having proved faithlefs to his wife, through
fondnefs for a concubine called C/i/tia, Cleobule, who
was jealous of him, perfuaded her fon Phoenix to ingra¬
tiate himfelf with his father’s miftrefs. Phoenix eaiily
fucceeded ; but Amyntor difeovering his intrigues, he
drew a curfe upon him, and the fon was foon after de¬
prived of his fight by divine vengeance. Some fay that
Amyntor himfelf put out his fen’s eyes, which fo cruelly
provoked him that he meditated the death of his father.
Reafon and piety, however, prevailed over paffion ; and
that he might not become a parricide, Phoenix fled from
Argos to the court of Peleus king of Phthia. Here he
was treated wdth tendernefs j Peleus carried him to
Chiron, who reftored his eyefight; foon after which he
was made preceptor to Achilles, his benefactor’s fon.
He was alfo prefented with the government of many ci¬
ties, and made king of the Dolopes. He went with his
pupil to the Trojan war ; and Achilles was ever grate¬
ful for the inftru&ions and precepts which he had re¬
ceived from him. After, the death of Achilles, Phoenix,
with others, was commiffioned by the Greeks to return
into Greece, to bring to the war young Pyrrhus. This
commiffion he fuccefsfully performed ; and after the fall
of Troy, he returned with Pyrrhus, and died in Thrace.
He was buried, according to Strabo, near Trachinia,
where a fmall river in the neighbourhood received the
name of Phoenix. There was another Phoenix, fon of
Agenor, by a nymph who was called Telephajfa, ac¬
cording to Apollodorus and Mofchus, or, according to
others, Epimedufa, Perimeda, or Agriope. He was, like
his brother Cadmus, and Cilix, fent by his father in
purfuit of his After Europa, whom Jupiter had carried
away under the form of a bull •, and when his inquiries
proved unfuccefsful, he fettled in a country, wffiich, ac¬
cording to fome, was from him called Phoenicia. From,
him, as fome fuppofe, the Carthaginians were called
Pceni.
PHOLAS, a genus of fhell-fiffi belonging to the or¬
der of vermes teftacea. See Conchology Index.
The wrord pholas is derived from the Greek, and fig-
nifies fomelhing which lies hid. This name they derive
3 F from
Phoenix,
Pholas.
P H O [ 410 ] P H O
from their property of making themfelves holes in the
earth, faBtl, wood, or ftone, and living in them. The
means of their getting there, however, are as yet en¬
tirely unknown. All that we can know with certainty
is, that they mud have penetrated thefe fubdances when
very fmall; becaufe the entrance of the hole in wdiich
the pholas lodges is always much lefs than the inner part
of it, and indeed than the diell of the pholas itfelf.
Hence fome have fuppofed that they were hatched in
holes accidentally formed in dones, and that they natu¬
rally grew of fuch a drape as was neceffary to fill the ca¬
vity.
The holes in which the pholades lodge are ufually
twice as deep, at lead, as the diells themfelves are long j
the figure of the holes is that of a truncated cone, ex¬
cepting that they are terminated at the bottom by a
rounded cavity, and their pofition is ufually fomewhat
oblique to the horizon. The openings of thefe holes are
what betray the pholas being in the done j but they are
always very fmall in proportion to the fize of the fidr.
There feems to be no progreffive motion of any animal
in nature lb dowr as that of the pholas} it is immerfed in
the hole, and has.410 movement except a fmall one to¬
wards the centre of the earth j and this is only propor¬
tioned to the growth of the animal. Its work is very
difficult in its motion *, but it has great time to perform
it in, as it only moves downward, finking itlelf deeper
in the done as it increafes itfelf in bulk. That part by
means of which it performs this, is a fieffiy fubdance
placed near the lower extremity of the drell } it is of the
drape of a lozenge, and is confiderably large in propor¬
tion to the fize of the animal j and though it be of a
foft fubdance, it is not to be wmndered at that in fo
long a time it is able, by condant wTork, to burrow into
■a hard done. The manner of their performing this may
be feen by taking one of them out of the done, and pla¬
cing it upon fome foft clay j for they will immediately
get to work in bending and extending that part allotted
to dig for them, and in a few hours they will bury them¬
felves in the mud in as large a hole as they had taken
many years to make in the done. They find little re-
fidance in fo foft a fubdance •, and the neceffity of their
hiding themfelves evidently makes them haden their
work. The animal is lodged in the lowTer half of the
hole in the done, and the upper half is filled up by a
pipe of a fleffiy fubdance and conic figure, truncated at
the end : this they ufually extend to the orifice of the
hole, and place on a level with the furface of the done}
but they feldom extend it any farther than this. The
pipe, though it appears fingle, is in reality compofed of
tw-o pipes, or at lead it is compofed of two parts fepara-
ted by a membrane. The ufe of this pipe or probofeis
is the fame with that of the probofeis of other diell-fifh,
to take in feawvater into their bodies, and afterwards to
throw it out again. In the middle of their bodies they
have a fmall green veffel, the ufe of which has not yet
been difeovered. This, when plunged in fpirit-of-wine,
becomes of a purple colour: but its colour on linen
does not become purple in the fun like that of the
murex.
The pholas is remarkable for its luminous quality,
which was noticed by Pliny, who obferves that it diines
in the mouth of the perfon who eats it; and if it touch
his hands or clothes, it makes them luminous. He alfo
lays that the light depends upon its moidure. The light
of this fidi has furnidied matter for various obfervations
and experiments to M. Reaumur and the Bolognian aca¬
demicians, efpecially Beccarius, wdio look fo much pains
with the fubject of phofphoreal light.
M. Reaumur obferves, that whereas other fiffies give
light when they tend to putrefcence, this is more lu¬
minous in proportion to its being freffi j that when
they are dried, their light will revive if they be mold-
ened either with freffi or fait water, but that brandy
immediately extinguidies it. He endeavoured to make
this light permanent, but none of his fchemes fuc-
ceeded.
The attention of the Bolognian academicians was en¬
gaged to this fubject by M. F. Mardlius in 1724, who
brought a number of thefe fiffies, and the dones in which
they were inclofed, to Bologna, on purpofe for their
examination.
Beccarius obferved, that though this fiffi ceafed to
dune when it became putrid, yet that in its mod putrid
date it would ffiine, and make the water in which it was
immerfed luminous when it was agitated. Galeatius
and Montius found that wine or vinegar extinguilhed
this light; that in common oil it continued fome days,
but in rectified fpirit of wine or urine hardly a minute.
In order to obferve in what manner this light was af¬
fected by different degrees of heat, they made ufe of a
Reaumur’s thermometer, and found that water rendered
luminous by thefe fiffies increafed in light till the hear,
arrived to 450, but that it then became fuddenly extinft,
and could not be revived again.
In the experiments of Beccarius, a folution of fea-falt
increafed the light of the luminous water ; a folution of
nitre did not increafe it quite fo much. Sal ammoniac
diminilhed it a little, oil of tartar per deliquium nearly
extinguiffied it, and the acids entirely. This water,
poured upon freffi calcined gypfum, rock-cryftal, ce-
rufe, or lugar, became more luminous. He alfo tried
the effeCls of it when poured upon various other fub-
ftances, but there was nothing very remarkable in them.
Afterwards, ufing luminous milk, he found that oil of
vitriol extinguilhcd the light, but that of tartar in¬
creafed it.
This gentleman had the curiofity to try how differ¬
ently coloured fubftances were affeded by this kind of
light j and having, for this purpofe, dipped feveral rib¬
bons in it, the while came out the brighteft, next to this
was the yellow, and then the green 5 the other colours
could hardly be perceived. It was not, however, any
particular colour, but only light, that was perceived in
this cafe. He then dipped boards painted with the dif¬
ferent colours, and alfo glafs tubes filled with fubftances
of different colours, in water rendered luminous by the
fiffies. In both thefe cafes, the red was hardly vifible,
the yellow was the brighteft, and the violet the dulieft.
But on the boards, the blue was nearly equal to the yel¬
low, and the green more languid ; whereas in the glaf-
fes, the blue was inferior to the green.
Of all the liquors to which he put the pholades, milk
was rendered the moft luminous. A fingle pholas made
feven ounces of milk fo luminous, that the faces of perfons
might be diftinguiffied by it, and it looked as if it were
tranfparent.
Air appeared to be neceffary to this light : for when
Beccarius put the luminous milk into glafs tubes, no "agi¬
tation would make it ffiine unlefs bubbles of air were mix¬
ed
Pholas.
P H 0 [41
Pholeys. ed with it. Alto Montius and Galeatius found, that, in
—v ' ‘ an exhautted receiver, the pholas loft its light, but the
water was fome times made more luminous : which they
afcribed to the riftng of bubbles of air through it.
Beccarius, as well as Reaumur, had many fchemes to
render the light of thefe pholades permanent. For this
purpofe he kneaded the juice into a kind of pafte with
llour, and found that it would give light when it was
immerfed in warm water •, but it anfwered beft to pre-
ferve the fiftr in honey. In any other method of prefer-
vation, the property of becoming luminous would not
continue longer than fix months, but in honey it had
lafted above a year j and then it would, when plunged
in warm water, give as much light as ever it had done.
See Barbut’s Genera Vermium, p. 14. &c.
PHOLEYS, or Foulies, are a people of Africa,
of very peculiar manners. Some authors tell us, that
the kingdom of Pholey, from whence they derive their
name, is divided from that of Jaloff by a lake called in
the language of the Mundingoes Cayor; and that it
ftretches from eaft to weft about 180 miles; but that,
though it extends a great way louth, its limits in that
direftion are not exactly afcertained.
Mr Moore, however, gives a very different account,
and fays, that the Pholeys live in clans, build towns,
and are in very kingdom and country on each fide of
the river ; yet are not fubjedl to any of the kings of
the country, though they live in their territories j for
if they are ufed ill in one nation, they break up their
towns, and remove to another. They have chiefs of
their own, who rule with fiach moderation, that every
a£! of government feems rather an aft of the people
than of one man. This form of government is eafily
adminiftered, becaufe the people are of a good and
quiet difpofition, and fo well inftrufted in what is juft
and right, that a man who does ill expofes himfelf to
univerfal contempt.
The natives of all thefe countries, not being avari¬
cious of land, defire no more than they can ufe ; and
as they do not plough with horfes or other cattle, they
can ufe but very little ; and hence the kings willingly
allow the Pholeys to live in their dominions, and cul¬
tivate the earth.
The Pholeys have in general a tawney complexion,
though many of them are of as deep a black as the
Mundingoes $ and it is fuppofed that their alliances
with the Moors have given them the mixed colour be¬
tween the true olive and the black. They are rather
of a low ftature, but have a genteel and eafy fhape,
with an air peculiarly delicate and agreeable.
Though they are ftrangers in the country, they are
the greateft planters in it. They are extremely indu-
ftrious and frugal, and raife much more corn and cot¬
ton than they confume, which they fell at reafonable
rates ; and are fo remarkable for their hofpitality, that
the natives efteem it a bleffing to have a Pholey town
in their neighbourhood j and their behaviour has gain¬
ed them fuch reputation, that it is efteemed infamous
for any one to treat them in an unhofpitable manner.
Their humanity extends to all, but they are doubly
kind to people of their race ; and if they know of any
one of their body being made a Have, they will rea¬
dily redeem him. As they have plenty of food, they
never fuffer any of their own people to want j but fup-
1 j p H o
port the old, the blind, and the lame, equally with the Pholeys,
others. • •
Thefe people are feldom angry ; and Mr Moore ob-
ferves that he never heard them abule each other ; yet
this mildnefs is far from proceeding from want of cou¬
rage, they being as brave as any people of Africa, and
very expert in the ufe of their arms, which are javelins,
cutlaffes, bows and arrows, and upon occafion guns.
They uiually fettle near fome Mundingo town, there
being fcarce any of note up the river that has not a
Pholey town near it. Moft of them fpeak Arabic,
which is taught in their fchools j and they are able to
read the Koran in that language, though they have a
vulgar tongue called Pho'ey. They are ftrift Maho¬
metans, and fcarce any of them will drink brandy, or
any thing ftronger than fugar and water.
They are fo Ikilful in the management of cattle, that
the Mundingoes leave theirs to their care. The whole
herd belonging to a town feed all day in the favannahs,
and after the crop is off, in the rice-grounds. They
have a place without each tow n for their cattle, fur-
rounded by a circular hedge, and within this enclofure
they raife a ftage about eight feet high, and eight or ten
feet w-ide, covered with a thatched roof j all the fide*
are open, and they afeend to it by a ladder. Round this
ftage they fix a number of ftakes, and when the cattle
are brought up at night, each beaft is tied to a feparate
flake with a ftrong rope made of the bark of trees. The
cows are then milked, and four or five men flay upon the
ftage all night with their arms to guard them from the
lions, tygers, and other wdld beafts. Their houfes are
built in a very regular manner, they being round ftruc-
tures, placed in rcw7s at a diftance from each other to
ar^'d fire, and each of them has a thatched roof fome-
wmat refembling a high-crowmed hat.
They are alfo great huntfinen, and not only kill lions,
tygers, and other wild beafts, but frequently go 20 or
30 in a company to hunt elephants q whofe teeth they
fell, and whofe flefti they fmoke-dry and eat, keeping it
for feveral months together. As the elephants here ge¬
nerally go in droves of 100 or 200, they do great mifehief
by pulling up the trees by the roots, and trampling down
the com j to prevent which, when the natives have any
fufpicion of their coming, they make fires round their
corn to keep them out.
They are almoft the only people who make butter,
and fell cattle at fome diftance up the river. They are
very particular hi their drefs, and never wear any other
clothes but long robes of white cotton, which they make
themfelves. They are always very clean/ efpecially the
women, who keep their houfes exceedingly neat. They
are, however, in fome particulars very fuperftitious : for
if they chance to know that any perfon who buys milk
of them boils it, they will from thenceforth on no con-
fideration fell that perfon any more, from their imagin¬
ing that boiling the milk makes the cow-s dry.
PHOLIS, in Natural Hi/lory, is an old name for
gypfums or plafter-ftones. The name is derived from
<pe>i<s, a fcale or fmallfiahe, becaufe they are compofed
of particles of that form.
Pholis, in Ichthyology, is the name of a fmall an-
guilliform fifin The back is brown, the belly is white,
the whole back and fides are fpotted, and the fkin is
foft, free of feales, but wdth a tough mucilagincus mat-
3 F 2 ter
P H 0 [4
Phonics, ter like the eel. This fpecies moft of all approaches to
Phromnim. j-|-IC a/aui}a • ar)(] though ufualiy larger, yei - l\Ir Ray
doubts rvheiher it really differs from it in any thing el-
fential 5 the diftinblion is its colour, which though a
very obvious is certainly a very precarious one.
PHONICS, the doctrine or fcience of found, other-
wife called Acoustics, which fee.
PHORMIUM, Flax-plant, (Phormium tcnax,
Forft.) is a name which we may give to a plant that
ferves the inhabitants of New Zealand i nil tad of hemp
and tlax. Of this plant there are two forts; the leaves
of both refemble thole of flags, but the flowers are
hnaller, and their clufters more numerous } in one kind
they are yellow, and in the other a deep red. Of the
leaves of thefe plants, with very little preparation, they
make all their common apparel, and alfo. their firings,
lines, and cordage, for every purpofe ; which are lo
much flronger than any thing we can make with hemp,
thaf they will not bear a comparifon.—From the fame
plant, by another preparation, they draw long {lender
fibres, which fliine like filk, and are as white as fnow :
of thefe, which are very ftrong, they make their fineft
cloths : and of the leaves, without any other preparation
than fplitting them into proper breadths, and tying the
Itrips together, they make their fifhing-nets, feme of
which are of an enormous fize.
The feeds of this valuable plant were brought over
intt> England ; but, upon the firil trial, appeared to
have loft their vegetating power. We underftand how¬
ever that it has fince fucceeded with the aid of artificial
heat.
The filamentous parts of different vegetables have
been employed in different countries for the fame me¬
chanic ufes as hemp and flax among us. Putrefadlion,
and in fome degree alkaline lixivia, deftroy the pulpy
or fleftiy matter, and leave the tough filaments entire.
Ey curioufly putrefying the leaf of a plant in water, we
obtain the fine flexible fibres which conftituted the bafis
of the ribs and-minute veins, and which form as it were
a Ikeleton of the leaf. In Madagafcar, different kinds
of cloth are prepared from the filaments of the bark of
certain trees boiled in ftrong ley } and fome of thefe
cloths are very fine, and approach to the fofinefs of filk,
but in durability come ftiort of cotton : others are coarfer
and ftronger, and laft thrice as long as cotton ; and of
thefe filaments they make fails and cordage to their vef-
lels. The ftalks of nettles are fometimes ufed for like
purpofes, even in France ; and Sir Hans Sloane relates,
in one of his letters to Mr Rdy, that he has been inform¬
ed by feveral, that muflin and callico, and moft of the
Indian linens, are made of nettles. A itrong kind of
cloth is faid to be prepared in fome of the provinces of
Sweden of hop-ftalks j and in the Tranfaftions of the
Swedilh Academy for 1750, we have an account of an
experiment relating to this fubjedl : A quantity of ftalks
was gathered in autumn, which was equal in bulk to a
quantity of flax fufficient to yield a pound after prepara¬
tion. The ftalks were put into water, and kept covered
with it during the winter. In March, they were taken
out, dried in a ftove, and dreffed as flax. The prepared
filaments weighed nearly a pound, and proved fine, foft,
and white ; they were fpun and wove into fix ells of fine
ftrong cloth. Unlefs the ftalks are fully rotted, which
will take much longer time than flax, the woody part *
12] P II O
will not ieparate, and the cloth Avill prove neither white PLofphite
nor fine. • P
PHOSPHATE is a faline body compofed of phof-,1 ^ U1S'
phoric acid united to lome bale, as for initance, lime,
which is called phofphate of lime. For an account of
the different phofphates, fee Chemistry and Minera¬
logy Index.
PHOSPHORUS, a name given to certain fubftan-
ces which {bine in the dark without emitting heat. Ey
this circumftance they are diftinguiftied from the pyro¬
phoric which though they take fire on being expofed to
tire air, are yet entirely deftitute of light before this ex-
polure.
Phofphori are divided into feveral kinds, known by
the names of Bo/ognian phofphorus, Mr Canton's phof-
phorus, Baldwin''s phofphorus, phofphorus of urine, &.c.
gf which the laft is by far the moft remarkable both
with refpedt to the quantity of light which it emits, and
its property of taking fire and burning very, fiercely upon
being llightly heated or rubbed. For the method of pre¬
paring thefe, and for an account of their properties and
combinatiens, fee Chemistry Index.
PHOTINIANS, in ecclefiaftical hifiory, were a fed!
of heretics in the fourth century who denied the divinity
of our Lord. They derive their name from Phot intis
their founder, who was biilrop of Sirmium, and a dif-
ciple of Marcellus. Photinus publifhed ih the year 343
his notions refpefting the Deity, which were repugnant
both to the orthodox and Arian fyftems. He aflerted,
that Jefus Chrift was born of the Holy Ghoft and the
Virgin Mary } that a certain divine emanation, which
he called the Word, defeended upon Plim ; and that be-
caufe of the union of the divine word with his human
nature, Fie was called the fon of God and even God
himfelf; and that the Holy Ghoft w as not a perfon, but
merely a celeftial virtue proceeding from the Deity.
Both parties condemned the biftrop in the councils of
Antioch and Milan, held in the years 345 and 347.
He was condemned alfo by the council at Sirmium in
351, and was afterwards degraded from the epifcopal
dignity, and at laft died in exile in the year 372 or
375. His opinions were afterwards revived by Soci-
nus.
PHOTIUS, patriarch of Conftantinople, was one of
the fineft geniufes of his time, and his merit raifed him
to the patriarchate •, for Bardas having driven Ignatius
from the fee, Photius was confecrated by Afbeftus in
859. He condemned Ignatius in a fynod, whereupon
the pope excommunicated him, and he, to balance the
account, anathematized the pope. Baftlius of Macedon,
the emperor whom Photius had reproved for the murder
of Michael the late emperor, expelled him, and reftored
Ignatius j but afterwards re-eftabliftied Photius, upon
Ignatius’s death, in 878. At laft, being wrongfully
accufed of a confpiracy againft the perfon of Leo the
philofopher, fon and fucceffor to Baftlius, be was expel¬
led by him in 886, and is fuppofed to have died loon
after. He wrote a Bibliotheca, which contains an exa-
men of 280 authors : we have alfo 233 epiftles of his ;
the Nomacanon under 14 titles ; an abridgement of the
adfts of feveral councils, &c. This great man was born
in Conftantinople, and was defeended from a very illu-
ftrious and noble family. His natural abilities were
very great, and he cultivated them with the greateft af-
ftduity.
Photius,
Phi.tfe
P H R [ 41
fiduity. There was no branch of literature, whether
facred and profane, and fcarcely any art or fcience, in
which he was not deeply verled. Indeed he appears to
have been by far the pie..! Left man of the age in which
he lived : and was fo intimately concerned in the chief
tranfadtions of it, that ecclefiahical writers have-on that
account called it Seculum Photianum. He was firft
raifed to the chief dignities of the empiie, being made
principal fecretary of date, captain of the guards, and a
fenator. In all thefe llations he acquitted himfelf with
a diftinblion fuitable to his great abilities j for he was a
refined ftatefman, as well as a profound fcholar. His
rife to the patriarchate was very quick 5 for when he was
chofen to that cilice he was only a layman : but that he
might be as it were gradually raifed to that dignity, he
was made monk the firft day, reader the next, and the
following days fub-deacon, deacon, and prieft. So that
in the fpace of fix days he attained to the higheft office
in the church. On the whole, however, his ardent love
of glory and unbounded ambition made birn commit ex-
ceiles which rendered him a fcourge to thofe about him.
Fabricius calls his Bibliotheca or library, non liber,
fed inf.gnis thsfaurus, “ not a book, but an illuftrious
treafure,” in which are contained many curious things,
relating to authors, and many fragments of works which
are no where elfe to be found. It was brought to light
by ikndreas Schottus, and communicated by him to
David Hoefchelius, who caufed it to be printed in 1601.
Schottus, confidering the great utility of this work, tranf-
lated it into Latin, and printed his tranflation alone in
1606. The Greek text, together with the .tranflation,
was afterwards printed at Geneva in 1611.
PHOTOMER, an in ft rumen t for afeertaining the in-
tenfity of light. See Optics Index.
PHRAATES, or Phrahates. There were four
kings of this name in Parthia. See Parthia.
PHRASE, in Grammar, an elegant turn or manner
of fpeech, peculiarly belonging to this or that occafion,
this or that art, or this or that language. Thus we fay,
an Italian phrafs, an eaftern phrafe, a poetical phrafe, a
rhetorical phrafe.
Phrase is fometimes alfo ufed for a fhort fentence or
fmall fet or circuit of words conftrufted together. In
this fenfe, Father. Buffier divides phrafes into complete
and incomplete.
Phrafes are complete where there is a noun and a
verb, each in its proper function } i. e. where the noun
exprefles a fubjefl, and the verb the thing affirmed of it.
Incomplete phrafes are thofe where the noun and the
verb together only do the office of a noun j confifting
of feveral words without affirming any thing, and which
might be expreffed in a Angle word. Thus, that which
is true, is an incomplete phrafe, which might be ex-
preiTed in one word, truth ; as, that which is true fatif-
fies the mind. i. e. truth fatisfies the mind.
PHRASEOLOGY, a collection of the phrafes or ele¬
gant expreffions in any language. See Phrase.
PHREATIS, or Phreattium, in Grecian antiquity,
was a court belonging to the civil government of Athens,
fituated upon the fea-thore, in the Piraeus. The name is
derived from xtto tv (pgsaflo?, becaufe it flood in a pit; or,
as others fuppofe, from the hero Phreatus. This court
heard fuch caufes as concerned perfons who had fled out
of their own country for murder, or thofe that fled for
involuntary murder, and who had afterwards committed
3 ]
P H R
!•: y a.
a deliberate and wilful murder. The firft who was tried Phreatis
in this place was Teucer, on a groundlefs fufpicion that
he had been accefl'ory to the death of Ajax. The ac-
cufed was not allowed to come to land, or fo much as
to call anchor, but pleaded his caufe in his bark j and if
found guilty, was committed to the mercy of the winds
and waves, or, as i’ome lay, fuffered there condign pu-
nifhment •, if innocent, he was only cleared of the iecond
fad, and, according to cuftom, underwent a twelve-
month’s banifliment for the former. See Potter’s G/v
Antiq. yol. i. p. 111.
PHRENETIC, a term ufed to denote thofe who,
without being abfolutely mad, are fubjedl to fuch ftrong
failles of imagination as in ibme meafure pervert their
judgement, and caiife them to aft in a way different
from the more rational part of mankind.
PHRENITIS, the fame with Phrensy an in¬
flammation of the meninges of the brain, attended with
an acute fever and delirium. See Medicine, N° 176 •,
ftrange degree of phrenzy which
of France, in the article France,
a genus of infefts, belonging to
See Entomology Ir.dex.
i-ila. From whence it
indent li¬
ft iv erf a l
alfo an account of a
attacked Charles VI.
N° 88, 90.
PHRYGANEA,
the order neuroptera.
PHRYGIA, a country in
derived its name is not certain : fome fay it was from
the river Phryx (now Sarabat), which divides Phry¬
gia from Caria, and empties itielf into the Plermus;
others from Phrygia, the daughter of Afopus and Eu- ^ ^
ropa. The Greek writers tell us, that the country took "uflGry,
its name from the inhabitants, and thefe from the townvol. in.’
of Brygium in Macedonia, from whence they firft paffed'P 44L&C
into Afia, and gave the name of Phrygia or Brygia to
the country where they fettled. Bochart is of opinion
that this traft was called Phrygia from the Greek verb
“ to burn or parch 5” rvhich, according to him,
is a tranflation of its Hebrew name, derived from a verb
of the fame fignification.
No lefs various are the opinions of authors as to the
exaft boundaries of this country ; an uncertainty which
gave rife to an obfervation made by Strabo, viz. that
the Phrygians and Myfians had diftinft boundaries ; but
that it was fcurce poflible to afeertain them. The lame
writer adds, that the Trojans, Myfians, and Lydians,
arc, by the poets, all blended under the common name
of Phrygians, which Claudian extends to the Pifidians,
Bithynians, and lonians. Phrygia Proper, according
to Ptolemy, whom we choofe to follow, was bounded
on the north by Pontus and Bithynia •, on the weft by
Myfia, Troas, the Afigean fea, Lydia, Maeonia, and
Caria ; on the fouth by Lycia •, on the eaft by Pamphy-
lia and Galatia. It lies between the 37th and qxft de¬
grees of north latitude, extending in longitude from 56
to 62 degrees. The inhabitants of this country, men¬
tioned by Ptolemy, are the Lycaones and Anthemilenii,
towards Lycia; and Moccadelis or Moccadine, the
Cyddefes or Cydiffes towards Bithynia ; and between
thefe the Peltini or Speltini, the Moxiani, Phylacenfes,
and Hierapolitae. To thefe we may add the Berecyn-
tes mentioned by Strabo.
Phrygia is commonly divided into the Greater and
Leffer Phrygia, called alfo Troas. But this divifion
did not take place till Troas was fubdued by the Phry¬
gians ; and hence it is more confidered by fome Roman
writers as a part of Phrygia, than Bithynia, Cappado-
P H It [4
• ‘Phrygia, cxa, or any other of the adjacent provinces. In after
ages, the Greater Phrygia was divided into two didrifts
or governments; one called Phrygia Pacatiana, from
Pacatianus, who, under Conftantine, bore the great of¬
fice of the prsefeftus prsetorio of the Ead ; the otlier
Phrygia Salutaris, from fome miraculous cures fuppof-
ed to have been performed there by the archangel Mi¬
chael.
This country, and indeed all Afia Minor, as lying
in the fifth and fixth northern climates, was in ancient
times greatly celebrated for its fertility. It abounded
in all forts of grain y being, for the mod part, a plain
country covered with a deep rich foil, and plentifully
watered by fmall rivers. It was in fome parts produc¬
tive of bitumen and other combudible fubdances. It
was well docked with cattle, having large plains and
padure grounds. The air was anciently deemed mod
pure and wholefome, though it is now in fome parts
thought extremely grofs, great part of the country ly¬
ing uncultivated.
In Phrygia Major were anciently feveral cities of
great celebrity $ fuch as Apanea, Laocicf.a, Hiera-
polis, Gordium, &c.—There were alfo fome famous
rivers luch as Marfyas, Maeander, &c. The Maean-
der is now called Madre or l.lindre, and was much ce¬
lebrated by the ancients for its windings and turn¬
ings ; from whence all fuch windings and turnings have
been denominated mceanders.
The Phrygians accounted themfelves the mod an¬
cient people in the world. Their origin, however, is ex¬
tremely dark and uncertain. Jofephusand St Jerome fay,
they were defcended from Togarmah, one of Gomer’s
fions 5 and that they were known to the Plebrews under
the name of Tigrammanes. The Heathen authors derive
them from the Brygians, a people of Macedonia. But
this is but mere conjefture •, and it is a conjecture to¬
tally unfupported, except by the fimilarity of names.
Bochart thinks that the Phrygians were the offspring
of Gomer the elded fon of Japhet j the word Phrygia
being the Greek tranflation of his name. Jofephus
makes Gomer the father of the Galatians \ hut he, by
the Galatians, mud neceffarily mean the Phrygians in¬
habiting that part of Phrygia which the Galatians had
made themfelves maders of j the defendants of Gomer
being placed by Ezekiel northward of Judiea, near
Togarmah (which Bochart takes to be Cappadocia),
long before the Gauls paffed over into Ada. We are
willing to let Gomer enjoy the fine country which Bo¬
chart is pleafed to give him, and allow him the honour
of being the progenitor of the Phrygians, fince we know
no other perfon on whom it can be conferred with any
degree of probability.
The ancient Phrygians are defcribed as fuperditious,
voluptuous, and effeminate, without any prudence or
fcrefight, and of fuch a fervlle temper, that nothing
but dripes and ill ufage could make them comply with
their duty ; which gave rife to feveral trite and well
4 ] P H R
known proverbs (a). They are faid to have been the Plirygia.
fird inventors of divination by the finging, flying, and v-—»
feeding of birds. Their mufic, commonly called the
Phrygian mood, is alleged by fome as an argument of
their effeminacy.
This government was certainly monarchical; for all
Phrygia was, during the reigns of fome kings, fubjeft to
one prince. Ninnacus, Midas, Manis, Gordius, and his
defendants, were undoubtedly fovereigns of all Phry¬
gia. But fome time before the Trojan war, we find
this country divided into feveral petty kingdoms, and
read of divers princes reigning at the fame time. Apol-
lodorus mentions a king of Phrygia contemporary with
Ilus king of Troy. Cedrenus and others fpeak of one
Teuthrans, king of a fmall country in Phrygia, whofe
territories were ravaged by Ajax, himfelf flain in Angle
combat, his royal feat laid in afhes, and his daughter,
by name Tecmeffa, carried away captive by the con¬
queror. Homer makes mention of Phoreys and Af ani-
us, b»th princes and leaders of the Phrygian auxiliaries
that came to the relief of Troy. Tantalus was king of
Sipylus only, and its diftrift ; a prince no lefs famous
for his great wealth, than infamous for his covetoufnefs
and other deteftable vices. That Phrygia was fubdued
either by Ninus, as Diodorus Siculus informs us, or by
the Amazons, as we read in Suidas, is not fufficiently
warranted. Moft authors that fpeak of Gordius tell
us, that the Phrygians having fent to confult an oracle
in order to know how they might put an end to the
inteftine broils which rent their country into many fac¬
tions and parties, received for anfwer, that the moft
effeftual means to deliver themfelves and their coun¬
try from the calamities they groaned under, was to
commit the government to a king. This advice they
followed accordingly, and placed Gordius on the throne.
A pamea was the chief emporium of all Afia Minor.
—Thither reforted merchants and traders from all parts
of Greece, Italy, and the neighbouring ifiands. Be-
fides, we know- from Syncellus, that the Phrygians
were for fome time mafters of the fea; and none but
trading nations ever prevailed on that element. The
country produced many choice and ufeful commodi¬
ties, which afforded confiderable exports. They had
a fafe coaft, convenient harbours, and whatever may in¬
cline us to think that they carried on a confiderable
trade. But as moft of the Phrygian records are loft,
we will not dwell on conjeftures lb difficult to be afcer-
tained.
We have no fet form of their laws; and as to their
learning, fince we are told that for fome time they
enjoyed the fovereignty of the fea, we may at leaft
allow them a competent Ikill in geography, geome¬
try, and aftronomy } and add to thefe, from what we
have faid above, a more than ordinary knowledge of
mufic.
Some have been of opinion that the Phrygian lan¬
guage bore a great refemblance to the Greek 5 but
the
(a) “ Phryges fero fapiunt, Phryx verberatus melior, Phryx non minus quam Spyntharus, &c.which pro¬
verbs intimate their fervile temper ; and fnow that they were more fit to bewail misfortunes in an unmanly manner,
than to prevent them by proper meafures. Their mufic, too, was fuited to their effeminate temper. The Doric
mood was a kind of grave and folid mufic; the Lydian a doleful and lamentable harmony; but the Phrygian chiefly
calculated to effeminate and enervate the mind. But this charafter is contradifted by others.
3
PER [4
Phrygia the contrary is manxfeft from the few Phrygian words
ii which have been tranfmitted to us, and carefully col-
J-'hryne. ^ gy Bochart and Rudbechius. To tfrefe we may
V add the authority of Strabo, who, after attempting to
derive the name of a Phrygian city from the Greek,
concludes, that it is a difficult matter to difcover any
fimilitude between the barbarous words of the Phrygian
language and the Greek. The Phrygian tongue, after
the experiment made by Pfammetichus king of Egypt,
was looked upon by the Egyptians as the molt ancient
language of ihe world. But other nations, particular¬
ly the Scythians, refufed to fubmit to their opinion, as
founded on an argument of no real weight. “ As the
two children (fay they) had never heard the voice of
any human creature, the word bee, or behkos, the firft
they uttered, was only an imitation of the goats that had
fuelled them, and happened to be a Phrygian word
fignifying bread (b).
We have already faid, that the Phrygians were fuper-
flitipus; their idols were confequently very numerous.
The chief of thefe was Cybele, who went by a variety
of names. (See Cybele). They alfo worffiipped Bac¬
chus under the name of Sabazios ; and his prieits they
called Sabot.
The hiltory of their kings is dark and uncertain, and
the dates of their feveral reigns and actions cannot now
be fixed ; we ffiall refer fuch of our readers, therefore,
as wiffi to know what is certain refpefting them, to the
Ancient Univerfal Pliftory, already quoted more than
once in the prefent article. See alfo Gordius, Midas,
&c. For Phrygia Minor, fee Troy.
PHRYGIAN stone, in Natural Hi/lory, is the
name of a ftone deferibed by the ancients, and ufed by
them in dyeing ; perhaps from fome vitriolic or alumi¬
nous fait contained in it, which ferved to enliven or fix
the colours ufed by the dyers. It w^as light and fpungy,
refembling a pumice •, and the wffiiteft and lighted wrere
reckoned the bed. Pliny gives an account of the me¬
thod of preparing it for the purpofe of dyeing, which was
by moidening it with urine, and then heating it red hot,
and differing it to cool.—This calcination was repeated
three times, and the done was then fit for ufe. Diof-
corides recommends it in medicine after burning j he
fays it was drying and adringent.
Phrygians, a chridian fea. See Cataphry-
gians and Montanists.
PHRYNE, was a famous proditute, wffio flourished
' at Athens about 328 years before the Chridian era.
She was midrefs of Praxiteles, who drewT her picture,
which wras one of his bed pieces, and was placed in the
temple of Apollo at Delphi. We are told that Apelles
painted his Venus Anadyomene after he had feen
Phryne on the fea-ffiore naked, and with diffievelled
hair. Phryne became fo very rich by the liberality of
her lovers, that ffie offered to rebuild Thebes at her
own expence, wffiich Alexander had dedroyed, provided
this inffription wras placed on the wTalls : Alexander di-
ruit, fed meretrix Phryne refecit; which was refufed.
See Plin. 34. c. 8. There wras another of the fame
name who was accufed of impiety. When ffie found
5 ] PER
that ffie was going to be condemned, ffie unveiled her Pbrymcus
bofom, which fo influenced her judges, that ffie was im- m M
mediately acquitted. ■ .. (-- ^
PHRYNICUS, a general of Samos, w ho endeavour¬
ed to betray his country, &c. -A flatterer at Athens.
 A tragic poet of Athens, difciple to Thtfpis. Pie
was the firft who introduced a female chara&er on the
ftage.
PHRYNIS was a mufician of Milylene. He was
the firft who obtained a mufical prize at the Panathenaea
at Athens. He added two drings to the lyre, which
had always been ufed with feven by ail his predeceffors.
He flouriffied about 438 years before the Chridian era.
We are told that hr. was originally a cook at the houfe
of Hiero king of Sicily. There w'as another of the
fame name, a writer in the reign of Commodus, who
made a colledlion, in 36 books, of phrafes and fentences
from the bed Greek authors, Sec.
PHRYXUS, in fabulous hiftory, was a fon of Atha-
mas king of Thebes, by Nephele. When his mother
was repudiated, he wras perfecuted wnih the mod inve¬
terate fury by his dep-mether Ino, becaufe he was to fit
on the throne of Athamas, in preference to the children
of a fecond wife. His mother apprized him of Ino’s
intentions upon his life •, or, according to others, his
preceptor 5 and the better to make his efcape, he fe-
cured part of his father’s treafures, and privately left
Bosotia wdth his filler Helle, to go to their friend and
relation Aretes king of Colchis. They embarked on
board a ffiip, or, as ive are informed by the fabulous
account of the poets and mythologids, they mounted
on the back of a ram, wffiofe fleece was of gold; and
proceeded on their journey through the air. The
height to which they were carried made Helle giddy,
and ffie fell into the fea. Phryxus gave his After a
decent burial on the fea-fliore, and after he had called
the place Hellefpont from her name, he continued his
flight, and arrived fafe in the kingdom of iEetes,
where he effered the ram on the altars of Mars. The
king received him with great tendernefs, and gave him
Chalciope his daughter in marriage. She had by him
Phrontis Melas, Argos Cylindrus, whom fome call
Cytorus. He was afterwards murdered by his father-
in-lawT, who envied him the poffeffion of the golden
fleece; and Chalciope, to prevent her children from
{haring their father’s fate, fent them privately from
Colchis to Boeotia, as nothing was to be dreaded there
from the jealoufy or refentment of Ino, wffio was then
dead. The fable of the flight of Phryxus to Colchis
on a ram has been explained by fome, who obferve,
that the ffiip on wffiich he embarked wras either called
by that name, or carried on her prow a figure of that’
animal. The fleece of gold is accounted for, by ob-
ferving that Phryxus carried awray immenfe treafures
from Thebes. Phryxus was placed among the conftel-
lations of heaven after death. The ram wffiich carried
him to Afia is faid to have been the fruit of Neptune’s
amour writh Theophane the daughter of Altis. This
ram the gods had given to Athamas in order to reward
his piety and religious life ; and Nephele procured it for
(b) Goropius Becanus makes ufe of the fame argment, to prove that the High Dutch is the original or mother-,
tongue of the world, becaufe the wrord beher.'m that language fignifies “ a baker,”
p h y r 4i
Plitiiiriafis her children, juft as they were going to he facrificed to
Pov'-dterr the jealoufy of Ino. Phryxus’s murder was fome time
after amply revenged by the Greeks •, it having occa-
fioned the famous expedition atchieved under Jafon
and many of the princes of Greece, which had for its
objedf the recovery of the golden fleece, and the punilh-
ment of the king of Colchis for his cruelty to the fon of
Athamas.
PHTHIRIASIS, the Lousy Evil, from <pk^, “ a
loufe.” Children are frequently its iubjects, but adults
are fometimes troubled with it. The increafe of lice,
when in a warm moift fituation, is very great *, but a
cold and dry one foon deftroys them. On the human
body four kinds of lice are dxftinguilhed : 1. The pedi-
cuh, fo called becaufe they are more troublefome with
their feet than by their bite. Thefe are in the heads of
children, efpecially if fore or fcabby ; and often in thofe
of adults, if they are flothful and nafty. 2. Crab-lice.
3. Body lice; thefe infeft the body, and breed in the
clothes of the nafty and flothful. 4. A fort which breed
under the cuticle, and are found in the hands and feet :
they are of a round form, and fo minute as often to
efcape the fight: by creeping under the fcarf-fkin they
caufe an intolerable itching ; and w hen the Ikin burfts
where they lodge, clufters of them are found there. See
Acarus.
A good diet and cleanlinefs conduce much to the de-
ftrudlion of lice. When they are in the head, comb it
every day; and, after each combing, fprlnkle the pulv.
fem. ftaph. agr. or coccul. Ind. among the hairs every
night, and confine it with a tight cap.
Codrochius, in his treatife on lice, fays, that the
powdered coc. Ind. exceeds all other means y and that
it may be mixed in the pulp of apple, or in lard, and ap¬
plied every night to the hair. Some writers afiert, that
if the pulv. cort. rad. faffafr. be fprinkled on the head,
and confined with a handkerchief, it deftroys the lice in
one night.
The body-lice are deftroyed by any bitter, four, fait,
or mercurial meditine, if applied to the fldn.
Black foap, and the flowers called cardaviine or lady's
frnoch, are faid to be fpecifics in all cafes of lice on the
human body.
PHTHISIS, a fpecies of confumption, occafioned by
an ulcer in*the lungs. See Medicine Index.
PHUL, or Pul, king of AiTyria, is by fome hiftori-
ans faid to be Ninus under another name, and the firft
founder of that monarchy : A renowned warrior. He
invaded Ifrael in the reign of Men ah cm, who became
tributary to him, and paid him 1000 talents of filver for
a peace. Flourifhed 771 B. C.
PHUT, or Phuth, the third fon of Ham (Gen. x.
6.). Calmet is of opinion, that Phut peopled either the
canton of Phtemphu, Phtemphuti, or Phtembuti, fet
down in Pliny and Ptolemy, whofe capital was Thara in
liOwer Egypt, inclining towards Libya ; or the canton
called Phtenotes, of which Buthus was the capital. The
prophets often fpeak of Phut. In the time of Jeremiah,
Phut W'as under the obedience of Necho king of Egypt.
Nahum (iii. 9.) reckons up his people in the number of
thofe who ought to have come to the afiiftance of No-
ammon or Diofpoli?.
PHYLACTERY, in the general, was a name given
by the ancients to all kinds of charms, fpells, or cha-
5 1
PHY
rasters, which they wore about diem, as amulets, lo pre- Pli)ia<ftery
ferve them from dangers or difeafes. i]
Phylactery particularly denoted a flip of parch-,
ment, wherein was written fome text of Holy Scripture,
particularly of the decalogue, which the more devout
people among the Jews wore on the forehead, the breaft,
or the neck, as a mark of their religion.
The primitive Chriftians alio gave- the name phijlac-
tevies to the cafes wherein they incloied the relicks of
their dead.
Phylatfteries arc often mentioned in th^ New7 Tefta*
ment, and appear to have been very common among the
Pharifees in our Lord’s time.
PHYLICA, Bastard Alaternus 5 a genus of
plants belonging to the pentandria clais. See Botany
Index.
PHYLLANTITUS, Sea-side Laurel; a genus of
plants belonging to the monoecia clafs. See Botany
Index.
PHYLLIS, in fabulous hiftory, was a daughter of
Sithon, or, according to others, of Lycurgus king of
Thrace, wdio received Demophoon the ion of Thefeus ;
who, at his return from the Trojan war, had flopped on
her coafts. She became enamoured of him, and did not
find him infenfible to her paflion. After fome months
of mutual tendernefs and affedlion, Demophoon fet fail
for Athens, where his domeftic affairs recalled him.
He promifed faithfully to return as foon as a month
was expired; but either his dillike for Phyllis, or the
irreparable fituation of his affairs, obliged him to vio¬
late his engagement: and the queen, grown defperate
on account of his abfence, hanged herfelf, or, accord¬
ing to others, threw herfelf dowm a precipice into the
fea and periflied. Her friends raifed a tomb over her
body, where there grew up certain trees, whofe leaves,
at a particular feafon of the year, fuddenly became rvet
as if fhedding tears for the death of Phyllis. Accord¬
ing to an old tradition mentioned by Servius, Virgil’s
commentator, Phyllis wTas changed by the gods into
an almond tree, which is called phylla by the Greeks.
Some days after this metamorphofis, Demophoon re-
vifited Thrace; and when he heard of the fate of Phyl¬
lis, he ran and clafped the tree, which, though at that
time ftripped of its leaves, fuddenly (hot forth, and
bloffomed as if ftill fenfible of tendernefs and love. The
abfence of Demopboon from the houfe of Phyllis has
given rife to a beautiful epiftle of Ovid, fuppofed to
have been wnitten by the Thracian queen about the
fourth month after her lover’s departure.—A country
woman introduced in Virgil’s eclogues.—The nurfe of
the emperor Domitian.—A country of Thrace near
Mount Pangaeus.
PHYSALIS, the Winter Cherry ; a genus of plants
belonging to the penlandria clafs. See Botany In¬
dex.
PHYSETER, or Spermaceti Whale, a genus
belonging to the order of cete. See Cetology In¬
dex.
PHYSIC, or Physick, the art of healing; properly
called Medicine. The wrord is formed from the Greek
(Petris, “ nature ;” in regard medicine confifts princi¬
pally in the obfervation of nature. See Physics and
Medicine.
PHYSICAL, fomething belonging to, or really
> exifting
2
P H Y
t 4i7 1
PHY
Phyfician. exifting In, nature. In this fenfe we fay a phyfical point,
in oppolition to a mathematical one, which only exifts
in the imagination j a phyfical fubflance or body, in op-
pofition to fpirit, or metaphyfical fubftance, &c.
PHYSICIAN, a perfon who profefTes medicine, or
the art of healing difeafes. See Medicine.
PHYSICIANS, College of, in London, ’Edinburgh, and Phyficiaus,
Dublin. See COLLEGE of Phyfcians. Phyfico-
PHYSICO-mathematics, includes thofe branches ma^esnia*
of phyfics which, uniting obfervation and experiment to 1 y ■
mathematical calculation, undertake to explain the phe¬
nomena of nature.
PHYSICS,
General de-'“P'A KEN in ite mofl enlarged fenfe, comprehends
fimtion of 1. whole fludy of nature j and Natural Philo-
P1JICS’ sophy is a term of the fame extent: but ordinary
language, and efpecially in this country, employs both -
of thefe terms in a much narrower fenfe, which it is pro-
2 per in this place to determine with fome precifion.
A-more Under the article Philosophy, we gave a particu-
particular lar account of that view of nature in which the ob-
of thTrcnn our altenti°n are confidered as conne6ted by
o tne term. gaufa(-jon. anJ we were at fome pains to point out
the manner in which this fludy may be fuccefsfully
cultivated. By a judiciou^ employment of the means
pointed out in that article, we difcover that the ob-
je£ls of our contemplation compofe an Universe,
which confills, not of a number of independent ex-
iftences folitary and detached from each other, but
of a number of fubftances conne&ed by a variety of
relations and dependencies, fo as to form a whole which
may with great propriety be called the System of Na¬
ture.
This affembling of the individual objects which com¬
pofe the univerfe into one fyftem is by no means the
work of a hafty and warm fancy, but is the refult of
fober contemplation. The natural hiftorian attempts
in vain to defcribe objects, by only informing us of
their fhape, colour, and other fenfible qualities. He
finds himfelf obliged, in defcribing a piece of marble,
for inflance, to tell us that it takes a fine polifh ; that
it flrikes fire with fleel $ that it burns to quicklime , that
it diffolves in aquafortis, and is precipitated by alkalies;
that with vitriolic acid it makes gypfum, &c. &c. &c.
and thus it appears that even the defcription of any
thing, with the view of afcertaining its fpecific nature,
and with the foie purpofe of difcrimination, cannot be
accomplifhed without taking notice of its various rela¬
tions to other things. But what do we mean by the
nature of any thing ? We are ignorant of its effence, or
what makes it that thing and no other thing. We
mull content ourfelves with the difcovery of |its qualities
or properties; and it is the alfemblage of thefe which
we call its nature. But this is very inaccurate. Thefe
do not conftitute its elfence, but are the confequences
of it. Yet this is all we fhall ever know of its nature.
Now the term property is nothing but a name expref-
ilng fome relation which the fubftance under confidera-
tion has to other things. This is true of all fuch terms.
Gravity, elafticity, fenfibility, gratitude, and the like,
exprefs nothing but certain matters of fad, which may
be obferved refpefting the objeft of our contempla¬
tion in different circumftances of fituation with regard
to other things. Gur diftinfl notions of individuals,
therefore, imply their relations to other things.
The flighted obfervation of the univerfe (hows an
evident connexion between ail its parts in their va-
Vol. XVI. Part II.
rious properties. All things on this earth are conneft-All paits of
ed with each other by the laws of motion and of mind. t^e un‘"
We are connected with the whole of the folar fyftemW^^1-
by gravitation. If we extend our obfervations to thenec^e(jia
fixed ftars, the connexion feem s to fail j but even here their va-
it may be obferved. Their inconceivable diftance, it 'i0115 F°*
is true, renders it impoflible for us to obtain any exten- Penties*
five information as to their nature. But thefe bodies
are conne&ed with the folar fyftem by the famenefs of
the light which they emit with that emitted by our fun
or any (hining body. It moves with the fame velocity,
it confifts (in moft of them at leaft) of the fame colours,
and it is reflefted, refra£ied, and inflefted, according to
the fame laws. ^
In this unbounded fcene of contemplation, our at- Our atten-
tention will be direfted to the different claffes of ob-tlon natu-
jefts nearly in proportion to the intereft we take in™^^^
them. There is nothing in which we are fo much tlie firft ia_
interefted as our fellow men ; and one of the firft fteps ftance to
that we make in our knowledge of nature, is an ac- °ur fellow
quaintance with them. We learn their difiinEiive na- meri‘
ture by attending to their charaBerifiic appearances j
that is, by obferving their aftions. We obferve them
continually producing, like ourfelves, certain changes
in the fituation or condition of furrounding objects;
and thefe changes are evidently direfted to certain ends
which refpeB themfelves. Obferving this fubferviency
of the effects which they produce to their own accom¬
modation, we confider this adjuftment of means to ends,
as the effedl of an intention, as we experience it to
be in our owrn cafe, where we are confcious of this in¬
tention, and of thefe its effedls. We therefore inter¬
pret thofe aftions of other men, where we obferve this Nature of
adjuftment of means to ends, as marks or figns of in-
tention in them fimilar to our own. And thus a qua¬
lity, or power, or faculty, is fuppofed in them by means
of its fign, although the quality itfelf is not immedi¬
ately cognifable by our fenfes. And as this intention
in ourfelves is accompanied by perception of external
objedls, knowledge of their properties, defire of good,
averfion from evil, volition, and exertion, without all
of which we could not or would not perform the aclions
wdiich w'e daily perform, we fuppofe the fame perception,
knowledge, defire, averfion, volition, and exertion in them.
Thus, by the conftitution of our mind, we confider
the employment of means, by which ends terminating in
the agent are gained, as the natural figns of defign or
intention. Art, therefore, or the employment of means,
is the natural fign of intention ; and wdierever we ob-
lerve this adjuftment of means to ends, we infer the a-
gency of defign.
A fmall acquaintance with the objefts around us,
obliges us to extend this inference to a great number
of beings befides our fellow men, namely, to the whole
3 G animal
4' 8 PH Y
Introduc- animal creation : for in all we obfcrve the fame fub-
■ t'^n' ferviency to the ends of the agent, in the changes
which we find them continually producing in the ob¬
jects around them. Thefe changes are all adjufted to
their own well-being. In all fuch cafes, therefore, rye
are forced, by the conftitution of our own minds, to infer
the exiitence of defign or intention in thefe beings alfo.
But in numberlefs changes produced by external ob¬
jects on each other, we obferve no fuch fitnefs in the
eftecls, no fuch fubferviency to the well-being of life
agent. In fuch cafes, therefore, wre make no fuch in-
6 ference of thought or defign.
All objects Thus, then, there is prefewted to our obfervation an
divided in- important dhtinction, by which we arrange all exter-
;imfun^r^ na^ °-je(^ts two claffes. The fir ft refembles our-
thinking felves, in giving external marks of that thought or in¬
beings. tention of which we are confcious j and we fuppofe in
them the other properties which w-e difcover in our-
felves, but cannot immediately obferve in them, viz.
thought, perception, memory, forefight, and all that
colleftion of faculties which we feel in ourfelves, and
which conftitute the animal. The other clafs of objects
exhibits no fuch appearances, and we make no fuch in¬
ference. And thus we divide the wThole of external nature
7 into the claffes of thinking and unthinking beings.
I;Jow we Our firft judgements about thefe claffes will be very
knowletl^16 ^naCcurate ’ an<^ we will naturally afcribe the differ-
©fmind.6 enceb which we do not very wTell underftand, to the
differences in organical ftrudlure, which wTe clearly ob¬
ferve. But when we have knocked down or perhaps
fmothered an animal, we find that it no longer gives
the former marks of thought and intention, and that it
now refembles the clafs of unthinking beings : And yet
it ftill retains all that fitnefs of organical ftruifture which
it had before j it feems only to want the intention and
the will. This obliges us to conclude that the diftinc-
tion does not arife from a difference in organical ftruc-
ture, but from a diftinft fubftance common to all think¬
ing beings, but feparable from their organical frame.
To this fubftance we afcribe thought, intention, contriv¬
ance, and all that colledtion of faculties which we feel
in ourfelves. To this fubftance in ourfelves we refer all
fenfations, pleafures, pains, remembrances, defires, pur-
pofes $ and to this aggregate, however imperfe&ly un-
derftood, we give the name mind. Our organical
frame, which feems to be only the inftrument of infor-
g mation and operation to the mind, we call our body.
The nature As the animating principle is not, like our body, the
©f mind as immediate objecft of the fenfes, we naturally conceive
humankind*1' to a ^fiance effentially different from thofe which
in rude are the. objects of our fenfes. The rudeft people have
ages. fliown a difpofition to form this conclufion. Obferving
that animal life was connected with breathing, it was
natural to imagine that breathing was living, and that
breath was life. It is a remarkable fa<ft, that in moft
languages the term for exprefiing breath is at leaft one
of the terms for expreffmg the foul; nil, Trnvpct, fpiri-
tus, in the Hebrew, Greek, and Latin, exprefs both ;
ghei/l, ox ghojl, in the Teutonic, comes from gheifen, to
“ breathe or figh dacha or duha, “ the foul,” in Scla¬
vonic, comes from duichat, “ to breathe j” fo in the
Gaelic does anal come from anam ; and the fame rela¬
tion is found between the two words in the Malay and
Other eaftern languages. We believe that moft perfons
can recoiled feirte traces of this notion in their early
SICS.
conceptions of things ; and many who do not confider Introduo
themfelves as uncultivated, believe that the foul quits , ^oa-
the body along with the lajl breath. Among the Tar- '
tar nations hanging is confidcrcd with particular horror,
on account of the ungraceful and filthy exit which the
foul is obliged to make from the body. 9
But the obfervation of the lame appearances of Their opi-
thought and intention in fifties and other animals ?ions not
which do not breathe, would foon ftiow that this was-i11^
but a rude conception. Very little refinement indeed
is neceffary to convince us that air or breath cannot
be the fubftance which thinks, wifties, and defigns j
and that the properties of this fubftance, whatever it
is, muft be totally different from, and incompatible
with, any thing that we know of the immediate objeds
of our fenfes.
Hence we are led to conclude that there are two Of the two
kinds of fubftances in nature: One, which is the prin-kinds of
ciple of fenfation \ and therefore cannot be the objed finances
of our fenfes, any more than light can be the objed of
the microfcope. This fubftance alone can feel, think, objeft of
defire, and propofe, and is the objed of reJleElion alone, refleftion
The objeds of our fenfes compofe the other clafs, and aIone> the
therefbre can have none of the other properties which °f the
are not cognofcible by the fenfes. Thefe* have all the ^ e'*
properties which our fenfes can difcover; and we can
have no evidence of their having any other, nor indeed
any conception of their having them. This clafs is
not confined to the unorganized maffes of matter ; for
we fee that the bodies of animals lofe after death that
organical form, and are aflimilated to all the reft of
unthinking beings. It has arifen from fuch views as
this, that while all nations have agreed to call this
clafs of objeds by the name body, which originally
expreffes our organical frame, fome nations, farther ad¬
vanced in cultivation or refinement, have contrived an
abftrad term to exprefs this general lubftance of which
all inanimate beings are compofed. Such a term we
have in the words materies, vXr,. It
Matter, jhen, is that fubftance which is immediate-The diftinc-
ly cognofcible by our fenfes. Whatever, therefore, tion be-
is not thus immediately cognofcible by our fenfes is tw?en ma*
not material, and is expreffed by a negative term, and'^matedll
called immaterial': hence it is that mind is faid to be fubftances
immaterial. It is of importance to keep in mind this h very im-
diftindion, merely grammatical. Little more is ne-l301^111*
ceffary for deteding the fophifms of Helvetius, Mira-
beau, and other fages of the Gallic fchool, who have
been anxious to remove the ties of moral and religious
obligation by lowering our conceptions of our intel-
ledual nature. It will alfo ferve to (how how haftily
they have formed their opinions who have aferibed to
the immediate agency of mind all thofe relations whicli
are obferved in the adions of bodies on each other at
a diftance. The conneding principles of fuch rela¬
tions e dijlante (if there be any fuch), are not the im¬
mediate objeds of our fenfes : they are therefore im.
material. But it does not follow that they are minds.
There may be many immaterial fubftances which are
not minds. We know nothing of any objed what¬
ever but by the obfervation of certain appearances
which fuggeft to our minds the exiftence and agency
of its qualities or powers. Such phenomena are the
natural figns of thefe qualities, and it is to thofe figns
that we muft always have recourfe when we with to
conceive
PHYSICS.
Introduc- conceive without ambiguity concerning them. What
ti°n. js {]ie charafterihic phenomenon of mind, or what is
v ' the dijlinguijhinv quality which brings it into view ? It
is intention : and it may be aflerted with the utmolf
confidence, that rve have no other mark by which
mind is immediately fuggefted to us, or that rvould
ever have made us fuppofe that there exifted another
mind befides our own. The phenomenon by which this
quality is luggefted to us is art, or the employment of
means to gain ends $ and the mark of art is the fup-
pofed conducivenefs of thefe ends to the well-being of
the agent. Where this train is not obferved, defign
or intention is never thought of \ and therefore where
intention is not perceived in any immaterial fubftance,
if any fuch has ever been obferved, it is an abufe of
language to call it mind. We do not think that even
perception and intelligence entitle us to give the name
mind to the fubftance in which they are inherent, be-
caufe it is from marks of intention alone that we infer
the exiftence of mind j and although thefe muft be
accompanied with perception and intelligence, it does
not follow7 that the fubftance which can perceive and
underftand muft alfo defire and propofe. However
difficult we may find it to feparate them, they are evi¬
dently feparable in imagination. And let not this afler-
tion be too haftily objefled to \ for the feparation has
been made by perfons moft eminent for their knowledge
and difcernment. When Leibnitz afcribed to his mo-
NADES, or what we call the ultimate ATOMS of. matter,
a perception of their fituation in the univerfe, and a mo¬
tion precifely fuited to this perception, he was the far-
theft in the world from fuppofing them animated or en¬
dowed with minds. It is true indeed, that others, wdio
think and call themfelves philofophers, are much more
liberal in their application of this term. A modern au¬
thor of great metaphyfical eminence fays, “ I call that
mind wThich moves, and that body which is moved.”
This clafs t?f philofophers alfert that no motion whatever
is begun except by the agency of an animating princi¬
ple, which (after Ariftotle) they call Nature, and
W'hich has in thefe days been exalted to the rank of a
god. All this jargon (for it is nothing elfe) has arifen
from the puzzle in wfttich naturalifts think themfelves
involved in attempting to explain the production of mo¬
tion in a body at a diftance from that body which is
conceived as the caufe of this motion. After having
been reluCtantly obliged, by the reafonings of Newton,
to abandon their methods of explaining fuch phenomena
by the impulfes of an intervening fluid, nothing feepa-
ed left but the affertion that thefe motions were pro¬
duced by minds, as in the cafe of our owm exertions.
Thefe explanations (if they dtferve the name) cannot
be objected to in any other w’ay than as an abufe of
language, and as the introduction of an unmeaning iar-
gon. We have, and can have, no notion of mind differ¬
ent from thofe of our owm minds ; and we difcover the
exiftence of other minds as w7e difcover the exiftence of
bodies, by means of phenomena which are charafteriftic
of minds, that is, wdiich refemble thofe phenomena that
follow the exertion of our own mental faculties, that is,
by the employment of means to attain felfilh ends;
and where fuch appearances are not obferved, no exift¬
ence of a mind is inferred. When wre fee a man fall from
the top of a houfe, and dalh out his brains on the pave¬
ment, we never afcribe this motion to his mind. Al-
419
though the fitnefs of many of the celeftial motions for Introduc-
moft important purpofes makes us fuppofe defign and , tl0n' .
contrivance fomewhere, and therefore a Supreme Mind, v"_ '
wc no more think of inferring a mind in the earth from
the fitnefs of its motions for purpofes moft beneficial to
its inhabitants, than of inferring a mind in a bit of
bread from its fitnefs for nourifhing our bodies. It is
not from the mere motions of animals that their minds
are inferred, but from the conducivenefs of thefe motions
to the well-being of the animal. 12
The term mind therefore, in the ordinary languageTiie mind
of all men, is applied to what defires and wills at the^Py11^
fame time that it perceives and underftands. If we duces mo-"
call that mind which produces motion, we muft derive tion, but
our notions of its qualities or attributes from obferving that which
their effeds. We muft therefore difcover the general c*ehres and
laws by which they aCt, that is, the general laws ob-'Vl‘S’
ferved in thofe motions which we confider as their ef-
fefts. Now7 thefe are the general law’s of motion ; and
in none of thefe can we find the leaft coincidence with
what w7e are accuftomed to call the laws of mind. Nay,
it has been the total want of fimilarity which has given
rife to the diftin&ipn which all men, in all ages and
countries, have made between mind and matter. This
diftinftion is found in all languages *, and it is an unpar¬
donable liberty which men take with language when
they ufe a term of diftinEiion, a fpec 'fc term, to exprefs
things of a different Ipecies. What thefe authors have
been pleafed to call mind, the whole world befides have
called by another name, force; which, though borrow¬
ed from our own exertions, is yet fufficiently diftincffive,
and never leads us to confound things that are differ¬
ent, except in the language of fome modern philofo¬
phers, who apply it to the laws of the agency of mind ;
and, when fpeaking of the force of motives, &c. com¬
mit the fame miftakes which the follow7ers of Ariftotle
commit in the ufe of the term mind. Force, in the lan¬
guage of thefe philofophers, means what connefls the
operations of mind ; as mind, in the language of Lord
Monboddo, is that which connedls the operations of
body.
Thofe are not lefs to blame who confider this Nature The prin.
of Ariftotle, this principle of motion, as an exiftence
or fubftance different both from matter and from the^y1”^.1101
minds of intelligent creatures. Ariftotle calls it in fome froni matter
places cea-Ki^ might wTith equal propriety, and and mind,
equal confiftency with his other dodirines, have called
mind, iirirsg rjAec, or an oaring Swains. Befides, w7e
have no evidence for the feparaLility of this rntring 4/v%yi
from body as we have for the feparability of fuch minds
as our own, the genuine ■^vxca. Nay, his whole doc¬
trines, when maturely confidered, affume their abfolute
infeparability.
This docdrine of elemental minds, therefore, as the Elemental
immediate caufes of the phenomena of the materialmmds are
an abate of
world,, is an abufe of language. It is a jargon ; and it iangua„e.
is a frivolous abufe, for it offers no explanation what- s ‘G '
ever. The phenomena are totally unlike the phenome¬
na of ordinary minds, and therefore receive no explana¬
tion from them ; and fince our knowledge of thefe yuaji
minds muft be derived entirely from the phenomena, it
wull be precifely the fame, although we exprefs it in
common language. We fliall not indeed raife the won¬
der of our hearers, as thofe do who fill the wrnrld with
minds which they never fufpeded to exift ; but we fliall
3 G 2 not
PHYSICS.
The dread
ful confe-
quences of
inateria-
fil'm.
\6
The extent
of philofo-
phical
kudy.
not bewilder their imaginations, confound their ideas,
and miilead their judgements.
We flatter ourfelves that our readers will not think
. thefe oblervations unfeafonable or mifplaced. Of all
miflakes that the naturalill can fall into, there is none
more fatal to his progrefs in knowledge than the con¬
founding things which are effentialiy different j and of
all the diftindtions which can be made among the ob¬
jects of our contemplation, there is none of equal phi-
lofophical importance with this between mind and mat¬
ter : And when we confider the confequences which na¬
turally follow from this confuflon of ideas, and particu¬
larly thofe which follow from finking the mental facul¬
ties of man to a level with the operations of mechanics
or chemiftry, confequences which the experience of the
prefent eventful day Ihows to be deftrudlive of all that
is noble or defirable in human nature, and of all that is
comfortable in this life, and which blafts every hope of
future excellence—we cannot be too anxious to have
this capital diftindlion put in the plaineft point of view,
and expreffed in the moft familiar charadfers, “ fo that
he who runneth may read.” When we fee the frenzy
which the reafoning pride of man has raifed in our
neighbourhood, and hear the didlates of philofophy in-
ceffantly appealed to in defence of whatever our hearts
fhudder at as {hocking and abominable j and when we
fee a man (a), of great reputation as a naturalift, and
of profeffed humanity and political moderation, congra¬
tulating his countrymen on the rapid improvement and
almoft perfedtion of philofophy j and after giving a (hort
fketch of the conflitution of the vifible univerfe, fum-
ming up all with a table of eledfive attradfions, and that
particular combination and mode of cryftallization which
conffitutes God (horrefco referens!)—is it not full
time for us to flop Ihort, and to alk our own hearts
“ whither are you wandering ?”■—But found philofophy,
reafoning from effedts to their caufes, will here liften to
the words of our facred oracles: “ By their fruits ye
lhall know them. Do men gather grapes of thorns, or
figs of thirties ?” The abfurd confequences of the flop¬
tical philofophy of Berkeley and Hume have been
thought, by men of undoubted difcernment, fufficient
reafons for rejedling it without examination. The no
lefs abfurd and the (hocking confequences of the mecha¬
nical philofophy now in vogue ihould give us the fame
abhorrence ; and fliould make us abandon its blood-ftain-
ed road, and return to the delightful paths of nature, to
lurvey the works of God, and feaft our eyes with the
dilplays of mind, which offer themfelves on every hand
in defigns of the moft extenfive influence and the moft
beautiful contrivance. Following the guidance of hea¬
venly wifdom, we (hall indeed find, that “ all her
ways are ways of pleafantnefs, and all her paths are
peace.”
Such is the fcene of our obfervation, the fubjedl of
philofophical ftudy. Its extent is almoft unbounded,
reaching from an atom to God himfelf. It is abfolute-
ly neceffary for the fuccefsful cultivation of this immenfe
field of knowledge, that it be committed to the care of
different cultivators, and that its various portions be
treated in different ways : and, accordingly, the various Introdue-
taftes of men have given this curiofity different direc- tion.
tions ; and the ftudy, like all other talks, has been pro- * 1 "'
moted by this divifion of labour.
Some philofophers have attended only to the appear¬
ances of fitnefs wdiich are exhibited in every quarter of
the univerfe; and by arranging thefe into different claf-
fes, and interpreting them as indications of thought aad
intention, have acquired the knowledge of many claffes
of fentient and intelligent beings, actuated by propenfi-
ties, and direfted by reafon. jy
While the contemplation of thefe appearances indi-The nature
cates thought and defign in any individual of one ofan^u^e*°f
thefe claffes, and brings its propenfities and purpofes *B"
of action, and the ends gained by thefe a£lions, into
view, the contemplation of thefe propenfities, purpofes,
and ends, occafions an inference of a much more gene¬
ral kind. All thefe intelligent beings'give indications
of knowledge and of power j but their knowledge
bears, in general, no proportion to their power of pro¬
ducing changes in nature, and of attaining important
ends •, and their power is neither always, nor in the
moft important cafes, the confequence of their know¬
ledge. Where the effect of their adlions is moft emi¬
nently conducive to their important interefts, the power
of attaining thefe valuable ends is generally independent
on any attention to the fitnefs of the means, and the ex¬
ertion is frequently made without even thinking of the
important end. The wrell-being of the individual is fe-
cured againft any danger from its ignorance, indolence,
or inattention, by an inftindtive propenfity, which leads
it to the performance of the neceffary aftion, which is
thus made immediately and ultimately defirable, with¬
out any regard to its ultimate and important end. Thus,
in our own nature, the fupport of animal life, and the
improvement ©f the means of fubfiftence by a knowledge
of the objedls which furround us, are not entrufted to
our apprehenfions of the importance of thefe ends, but
are committed to the furer guides of hunger and curio-
flt^' ., . rS
The fame obfervers difcover a connexion between There is a
the individuals of a clafs, different from that which connexion
arifes from the mere refemblance of their external ap- between
pearance, or even of their propenfities and purfuits > duals'of^"
the very circumftances which produced the claflifica- ciafs 0f ani.,
tion. They obferve, that thefe propenfities are fuch, mals differ-
that while each individual feeks only its own enjoy-ent from
ment, thefe enjoyments are in general fuch as contri-
bute to the fupport of the fpecies and the enjoyment ern nce'
of other individuals. Thus, in the claffes of animals,
and in human nature, the continuance of the race, and
the enjoyment of the whole, are not entrufted to the
apprehenfion we entertain of the importance of thefe
ends, but are produced by the operation of fexual love
and the love of fociety.
The fame obfervers find that even the different claffes There is al-
of fentient beings are connefled together ; and while f° a fink of
the whole of each clafs aim only at their own enjoy-10”ne<^‘on
ment, they contribute, in fome way or other, to the
tvell-being of the ether claffes. Even man, the felfilh ings ot dif-
lord ferent claff
fes.
(a) M. de la Metherie, editor of the Journal de PhijJique.
January and July.
See his prefaces to the volumes for 1792 and 1793*
PHY
Ifttroduc- lord of this fublunary world, is not the unconnected
tio^ inhabitant of it. He cannot, in every inftance, reap
'' vall the fruits of his lituation, without contributing to
the enjoyment of thoufands of the brute creation. Nay,
it may be proved to the fatisfaCKon of every intelligent
man, that while one race of animals, in confequence of
its peculiar propenfities, fubfiits by the deitruftion of
another, the fum total of animal life and enjoyment is
prodigioufly increafed. See a very judicious dilTertation
on this curious and puzzling fubject, entitled A P/iilo-
fophical Survey of the Animal Creation; where it appears
that the increafe of animal life and enjoyment which is
produced by this means, beyond what could poffibly
obtain without it, is beyond all conception. See like-
wife the lafl edition of King's Origin of Evil, by Dr Law
20 late bifhop of Carlifle.
The end of Thus the whole affemblage feems conneCled, and
this connec-j0intly employed in increafing the fum total of poflible
fion ]:iappinefs> This fitnefs of the various propenfities of
tion ofVa'p- fentient and intelligent beings, this fubferviency to a
pmefs. 1 general purpofe, ftrikes thefe obfervers as a mark of
intention, evidently dhlinct from, and independent of,
all the particular intentions, and fuperior to them all j
and thus it irrefiftibly leads them to infer the exiltence
of a supreme mind, direding the whole of this in¬
tellectual system, while the individuals of which
it conlifts appear the unconfcious intlruments in the hand
of a great Artift, with which he executes his grand and
beneficent purpofes.
But the obfervation goes yet further. The bodies
of the inanimate creation are not only connected with
each other by a mutual dependence of properties, and
the relation of caufation, but they are alfo connected
with the fentient beings by a fubferviency to their
purpofes of enjoyment. The philofopher obferves
that this connection is admirably kept up by the con-
Itancy of natural operations and the expectations of
intelligent beings. Had either of thefe circumftances
been wanting, had either the operations of nature been
without rule, or had fentient beings no perception or
expectation of their uniformity } the fubferviency would
be totally at an end. This adjuftment, this fitnefs, of
which the effeCt is the enjoyment of the fentient inha¬
bitants of the univerfe, appear to be the effeCt of an
intention of which this enjoyment is the final caufe.
This eonftancy therefore in the operations of nature,
both in the intellectual and material wrorld, and the
concomitant expectation of fentient beings, appear
the effeCts of laws impofed on the different parts of
the univerfe by the Supreme Mind, who has formed
both thefe claffes of beings fo admirably fuited to each
other.
To fuch obfervers the world appears a WORK OF art,
a fyftem of means employed for gaining certain pro-
pofed ends, and it carries the thoughts forward to an
artist •, and we infer a degree of fkill, power, and
good intention in this Artift, proportioned to the in¬
genuity, extent, and happy effeCt which we are able
to difcern in his works. Such a contemplation of na¬
ture, therefore, terminates in Natural Theology,
or the difcovery of the exiftence and attributes of
Our mode G°D*
of reafoning Our notions of this Supreme Mind are formed from
on the ope- the indications of defign which we obferve, and which
rations of we interpret in the fame way as in the aCtions of men.
31
All nature,
animate
and inani¬
mate,
thinking,
and un¬
thinking,
is con¬
certed.
The origin
of natural
theology.
SICS. 42£
Thefe notions, therefore, will differ from our notions Ir.troduc-
of other minds only in the degrees which we are able to , tl0r!- ,
obferve, and which we affign to thefe faculties j for the
phenomenon or the effeCt is not only the mark, but alfo
the meafure of its fuppofed caufe. Thefe degrees mult
be afcertained by our own capacity of appreciating the
extent, the multiplicity, and the variety of the contri¬
vance. Accordingly, the attributes of the Supreme
Mind, in the theological creed of a rude Indian, are
much more limited than in that of a European philoib-
pher. In proportion as our underftandings are enlar¬
ged, and as our acquaintance with the operations of na¬
ture around us is extended, we fhall perceive higher de¬
grees of power, of fkill, and of kind intention: and fince
we find that the fcene of ebfervation is unbounded, we
cannot affix any boundaries to thefe attributes in our
own imagination, and we are ready to fuppofe that they
are infinite or unbounded in their own nature. When
our attentive furvey of this univerfe, and a careful com-
parifon of all its parts, as far as we can underftand or
appreciate them, have made us conclude that it is
one defign, the work of one Artijl; we are under the
neceffity of inferring, that, with refpeCt to this univerfe,
his power, wifdom, and benevolence, are indeed infi-
nite. _ 24
When men have been led to draw’ this conclufion from nie fyftem
the appearances of fitnefs wffiich are obferved every- of nature
where around them, they confider that conftancy which15 S°ver^"
they obferve in natural operations, whether in the ma-eeraUaws.
terial or the intelleftual fyftem, and that expectation of,
and confidence in, this conftancy, wdiich renders the
univerfe a fource of enjoyment to its fentient inhabitants,
as the confequences of laws impofed by the Almighty
Artift on his works, in the fame manner as they would
confider the conftancy in the conduCt of any people as
the confequences of laws promulgated and enforced by
the fupreme magiftrate.
There can be no doubt of this view of nature being The nature
extremely captivating, and likely to engage the curio- and pro-
fity of fpeculative men*, and it is not furprifing that °cthe
the phenomena of mind have been keenly ftudied in
all ages. This part of the ftudy of nature, like all
others, was firft cultivated in fubferviency to the wrants
of focial life \ and the general laws of moral fentiment
were the firft phenomena which wrere confidered with 26
attention. This gradually ripened into a regular fyf-The rife of
tem of moral duty, accompanied by its congenial ftudy, rl10raI fen'
the inveftigation or determination of the fummurn
nutn, or the conftituents of human felicity j and thefeduty,
tw70 branches of intelleftual fcience were always kept in
a ftate of alfociation by the philofophers of antiquity.
Jurifprudence, the fcience of government, legiflation,
and police, wrere alfo firft cultivated as arts, or at leaft
in immediate fubferviency to the demands of cultivated
fociety; and all thefe fo nearly related parts of the
ftudy of human nature, had made a very confiderable
progrefs, in the form of maxims or precepts for dire£t-
ing the conduft, before fpeculative men, out of mere
curiofity, treated them as fubjedls of philofophical
ftudy Our moral fentiments, always involving a feel¬
ing of obligation, are exprelfed in a language con.-
fiderably different from the ufual language of purs
philofophy, fpeaking of things which ought to be, rather
than of things which are; and this diftinftion of lan¬
guage was increafed by the very aim of the writers,.
which 5
42 2
PHY
.
The origin
telledtual
Sciences.
Introduc- which was generally to influence the conduct as well
non. , as the opinions of their fcholars. It was referved for
v modern times to bring this fludy into the pure form
of philofophy, by a careful attention to the phenome¬
na of moral fentiment, and claffing thefe according to
their generality, and afcertaining their refpeftive ranks
by an appeal to experiment, that is, to the general
conduct of mankind : and thus it happens that in the
modern treatifes on ethics, jurifprudence, &c. there is
lefs frequent reference made to the qfficia or duties, or
to the conftituents of the fttinmum hokum, than among
the ancients, and a more accurate defcription of the
human mind, and difcrimination of its various moral
feelings.
It was hardly poflible to proceed far xA in thefe dif-
of logic and quifitions without attending to the powers of the un-
other in- dei-ftanding. Differences of opinion were fupported
by reafonings, or attempts to reafohing. Both tides
could not be in the right, and there muft be fome
court of appeals. Rules of argumentation behoved to
be acquiefced in by both parties; and it could hardly
efcape the notice of fome curious minds, that thei'e
were rules of truth and falfehbod as well as of right
and wrong. Thus the human underjlanding became an
objeft of ttudy, fii-ft in fubferviency to the demands of
the mofalitls, but afterwards for its own fake ; and it
gradually grew up into the fcience of logic. Still
further refinement produced the fcience of metaphyfics,
or the philofophy of univerfals. But all thefe were
in fa£i pofterior to the doctrines of morals j and dif-
quifitions on beauty, the principles of tafte, the pre¬
cepts of rhetoric and criticifm, were the laft additions
to the ftudy of the phenomena of mind. And now,
fince the world feems to have acquiefed in the mode
of inveftigation of general laws by experiment and
obfervation, and to agree that this is all the know¬
ledge that we can acquire of any fubjeft whatever, it
is to be expected that this branch of philofophical dif-
cuffxoh will attain the fame degree of improvement
(eftimated by the coincidence of the dodtrines with
fadt and experience) that has been attained by fome
others.
The occupations, however, of ordinary life have
oftener diredted our efforts towards material objedts,
aS
The par¬
tial prac¬
tice of na- and engaged our attention on their properties and re-
tural phi- ]atJons; and as all fciences have arifen from arts, and
lofophy
preceded
its ftudy
as a fci-
were originally implied in the maxims and precepts of
thofe arts, till feparated from them by tlxe curious
fpeculatift, the knowledge of the material fyftem of
nature was poffeffed in detached fcraps by the pradti-
tioners in the various arts of life long before the natu¬
ral philofopher thought of colledling them into a body
of fcientific dodlrines. But there have not been want¬
ing in all ages men of curiofity who have been ftruck
by the uniformity of the operations of nature in the
material world, and were eager to difcover their
caufes.
Accordingly, while the moralifts and metaphyficians
turned their whole attention to the phenomena of
mind, and have produced the fciences of pneumatolo-
gy, logic, ethics, jurifprudence, and natural theology,
thefe obfervers of nature have found fufficient employ¬
ment in confidering the phenomena of the material
world.
The bodies of which it confifts are evidently con-
3
S I c s.
nedled by means of thofe properties by which we Introdue-
obferve that they produce changes in each other’s fi- < ^on-
tuation. This alfemblage of objedb may therefore be
juftly called a fyftem. We may call it the material The nature
system. It is frequently termed NATURE j and the of the ma-
terms NATURAL APPEARANCES, natural causes, na- teiial fy-
tural laws, have been generally reftridled to thofe
which take place in the material fyftem. This re- nition of
ftridtion, however, is improper, becaufe there is no dif- that and
ference in the manner in which we form our notions other
of thofe laws, and reafon from them, both with re- terms»
fpedl to mind and body. Or if there is to be any
reftriflion, and if any part of the ftudy of the univerfe
is to be excluded in the application of thefe terms, it
is that part only which conliders moral obligation, and
rather treats of what ought to be than of what is. As
has been already obferved, there is a confidferable dif¬
ference in the language which muft be employed ; but
ftill there is nont: in the principles of inveftigation. -
We have no proof for the extent of any moral law
but an appeal to the feelings of the hearts of men, indi¬
cated by the general laws or fafts which are obferved in
their actions. .
But this is only a queftion of the propriety of lan-- The unre-
guage. And no great inconvenience would ax-ife from ftn&ed
the reftri£tion now mentioned if it were, fcrupuloufly
adhered to; but unfortunately this is not always the t^efe0nae
cafe. Some authors ufe the term natural law to ex- terms are
prefs every coincidence of faft; and this is certainly pled, and
the proper ufe of the term. The French writers ge-{.tsbacl con-
nerally ufe the term lei phyfique in this enlarged fenfe. ences*
But many authors, milled by, or taking advantange of,
the ambiguity of language, after having eftablifhed a
law founded on a copious and perhaps unexcepted in-
duction of the phenomena of the material fyftem (iri
which caffe it muft be confidered in its reftri&ed fenfe),
have, in their explanation of phenomena, extended
their pidnciple much farther than the induction on
which they had founded the exiftence of the phyfical
law. They have extended it to the phenomena of
mind, and have led their followers into great and dan¬
gerous miftakes. Languages, like every other pro¬
duction of human Ikill, are imperfeCt. They are de¬
ficient in terms, and are therefore figurative. The
moft obvious, the moft frequent, and the moft inte-
refting ufes of language, have always produced the
appropriated terms, and the progrefs of cultivation has
never completely fupplied new ones. There are cer¬
tain analogies or refemblances, or certain affpeiations
of ideas, fo plain, that a term appropriated to one
Very familiar objeft will ferve to fuggeft another ana¬
logous to it, when aided by the concomitant circum-
ftances of the difeourfe ; and this with fufficient pre-
cifion for the ordinary purpofes of focial communica¬
tion, and without leading us into any confiderable
miftakes: and it is only the rare and refined difquifi-
tians of the curious fpeculatift that bring the poverty
and imperfeftion of language into view, and make us
wiffi for words as numerous as our thoughts. There
is hardly a fentence, even of common difeourfe, in
which there are not feveral figures either of fingle
words or of phrafes ; and when very accurate dxfcrimi-
nation is reqxxired, it is almoft impoflible to find words
or phrafes to exprefs diftinClions which we clearly feel.
We believe it impoffible to exprefs, by the fcanty vo¬
cabulary
m
P H Y S
Intrcxluc-
tiotl. '
31
The term
phyjics de¬
fined as it
is generally
underftood
in Britain.
32
The phe¬
nomena of
the mate¬
rial fyftem
arranged
into two
clafles.
33
Examples
of thofe of
the firfi:
clafs.
cabulary of tue Hebrews, tbe nice diftiinStions of
thought which are row familiar to the European phi-
lofopher. In nothing dees this imperfection of lan¬
guage appear fo remarkably as in what relates to mind.
Being a late lubject of feparate difeuffion, and intereft-
ing only to a few fpeculatilis, we have no appropriated
vocabulary for it ; and all our difquifitions concerning
its operations are in continual metaphor or figure, de¬
pending on very flight analogies or refemblances to
the phenomena of the material world. This makes
tire utmoft caution neceflary j and it juftifies the Bri-
tiflr philofophers, who have been tbe moft fuccefsful
in profecuting tbe ftudy of the intellectual fyftem, for
having, alma ft without exception, reftriCted the terms
natural laws, natural caufes, natural philofophy, and
fuch like, to the material fyftem. With us pneuma-
tology makes no part of phyftcs. And we may ven¬
ture to affirm, that the fciences have fared better by
the reftriClion of the terms. In no country has tbe
fpirit of liberal difeuffion been more encouraged and
indulged than in Britain 5 and her philolophers have
been equally eminent in both branches of fcience.
Their performances in ethics, jurifprudence, and na¬
tural theology, are confidered by all our neighbours as
tbe fountains of knowledge on thefe fubjeCls; and
Locke and Clarke are names no lefis familiar on the
continent than Newton. The licentious and degrading
doCtrxnes of the Gallican fchool have as yet made little
irapreflion here } and man is ftill confidered among us as
a glorious creature, born to, and fitted for, the nobleft
profpeCts.
Phyfics, then, is with us the ftudy of the material
fyftem, including both natural hiltoiy and philofophy.
The term is not indeed very familiar in our language *,
and in place of physic us and difeiplina physica, we more
generally ufe the terms naturalijl and natural knowledge.
The term naturalpJiilofophi/, in its common acceptation,
is of lefs extent. The field of phyfical inveftigation is
ftill of prodigious extent 3 and its difterent quarters re¬
quire very different treatments, make very different re¬
turns, and accordingly have engaged in their particular
cultivation perfons of very different talents and taftes. It
is of fome importance to perceive the diftinftions,
and to fee how the wants and propenfities of men have
led them into the different paths of inveftigation 3
for, as has been more than once obferved, all fciences
have fprung from the humble arts of life, and both
go on improving by means of a clofe and conftant cor-
refpondence.
All the phenomena of tbe material fyftem may
be arranged into two clafles, diftinguiftted both by
their objeCts and by the proper manner of treating
them. ■
The fir ft clafs comprehends all the appearances which
are exhibited in the fenjible motions of bodies, and their
aClions on each other producingmotion.
The lecond clafs comprehends the appearances which
are exhibited in the mfenjible motions and adlions of the
invifible particles of matter.
Of the phenomena of the firft clafs we have examples
in the planetary motions, the motions of heavy bodies,
the phenomena of impulfe, the motions and aclions of
machines, the preffure and motions of fluids, the fenfible
aftions of magnetical and eledlrical bodies, and the mo¬
tions of light.
* C S. 423
We have examples of the fecond clafs in the pheno- Introduc-
mena of heat and mixture, and thofe exhibited in the, ^°n’
growth of animals and vegetables, and many pheno- 2^'“’'
mena of folid, fluid, magnetical, electrical, and lumi-and 0f thofe
nous bodies, in which no change of place can be ob-of the fe-
ferved.
Thus it appears that there is a diftinCtion in the phe* ■j-]);s'5a'’r
nomena fufficiently great to warrant a diviiion of the ,-angement
ftudy, and to make us expeCt a more rapid improve-is appa-
ment by this divifion. Nay, the divifion has been''entIy re¬
made by nature itfelf, in the acquaintance which mentural*
have attained with her operations without ftudy, be¬
fore fcience appeared, and while art conftituted all our
knowledge. 35
Before man had recourfe to agriculture as the moft Of the pro¬
certain means of procuring fubftfttnce, our acquaintance ^
with external fubftances was principally that of the na-^’^jg
tural hiilorian 5 confifting of a knowledge of their fitnefs ages,
for food, medicine, or accommodation, their places of 1
growth or habitation, and the means of procuring them, 37
depending on their manner of life or exiftence. It re-The origin
quired a ftudied attention to thefe circumftances to give °^a&r'cu^"
rife to agriculture, which therefore generally made hs fic'^ur^er'v
appearance after men had been in the praClice of keep-and che-
ing flocks 3 by which means they were more at their miftry.
cafe, and had fome leifure to attend to the objedls
around them, and in particular to thefe circumftances of
foil and weather which affedted the growth of their
pafture.
When agriculture and a rude medicine were thus efta-
bliftied, they were the firft arts which had their founda--
tion in 3. fystem of laws, by which the operations of na¬
ture were oblerved to be regulated ; and with thefe arts
we may begin the generalJhidy of nature, which was
thus divided into two different branches.
The rude phyftcian would be at firft a colle&or of
fpeefes ; but by degrees he would obferve refemblances .
among the operations of his drugs, and would clafs them
according to thefe refemblances. He would thus come
to attend lefs to the drug than to its mode of operation 3
and would naturally fpeculate concerning the connection
between the operation and the economy of animal life.
His art now becomes a fcientific fyftem, connefted by
principle and theory, all proceeding on the obfervation
of changes produced by one kind of matter on another,
but all out of fight. The frequent recourfe to the vege¬
table kingdom for medicines would caufe him to attend
much more minutely to the few' plants which he has oc-
cafion to ftudy than the hufbandman can do to the mul¬
titude he is obliged to rear. The phyfician mull learn
to think, the hufbandman to work. An analogy be¬
tween the economy of animal and vegetable life could
hardly fail to engage the attention of the phyfician, and
would make him a botanift, both as a claflifier of plants
and as a philofopher.
He would naturally expeft to unite the fervices of his
drugs by .combining them in his recipes, and would be
furprifed at his difappointments. Cuiious and unexpeft-
ed changes would frequently occur in his manipulations :
the fenfible qualities, and even the external appearances
of his fimples, would be often changed, and even invert¬
ed by their mixture 3 and their medicinal properties
would frequently vanifti from the compound, and new
ones be induced. Thefe are curious, and to him inte-
refting fads 3 and he would naturally be inquifitive af~
) ter *
%
424
Introduc¬
tion.
38
The origin
of the
knowledge
of the me¬
chanical
.powers.
39. .
The origin
of mathe-
SOatics.
PHY
ter tire principles whicli regulate thefe changes. His
, {kill in this would by degrees extend beyond the imme¬
diate ufe for the knowledge ; and the more curious fpe-
culatift would lay the foundations of a moft extenfive and
important fcience, comprehending all the phenomena bf
heat and mixture.
Along with this, and fpringing from the fame fource,
another fcience muft arife, contemplating the appear¬
ances of animal and vegetable life, and founded on a
careful obfervation and accurate defcription of the won¬
derful machine. The moll incurious of men have in all
ages been affefted by the difplays of wifdom and contri¬
vance in the bodies of animals, and immediately enga¬
ged in inveftigation into the ufes and fun£fions of their
various parts and organs; The phenomena have been
gradually difcriminated and arranged under the various
Heads of nutrition, concoftion, fecretion, abforption, af-
limilation, rejection, growth, life, decay, difeafe, and
death j and, in conformity to the doftrines which have
with greater or lefs evidence been eftablilhed on thefe
fubjedls, the action of medicines, and the whole practice
of phyfic and furgery, has been eftablilhed in the form
of a liberal or fcientific art.
The hufbandman in the mean time muft labour the
ground which lies before him. He, too, is greatly in-
terefted in the knowledge of the vegetable economy, afid
forms fome fyltems on the fubjeft by which he regulates
his labours : but he fees, that whatever is the nature of
vegetable life, he muft work hard, and he fearches a-
bout for every thing which can tend to diminifti his la¬
bour. The properties of the lever, the wedge, and the
inclined plane, foon become familiar to him j and with¬
out being able to tell on what their efficacy depends, he
ufes them with a certain fagacity and effeft. The
ftrength of timber, the preflure and force of water, are
daily feen and employed by him and other artifans who
labour for their mutual accommodation ; and fome rude
principles on thefe fubje£ls are committed to memory.
Many tools and fimple machines are by this time fami¬
liar } and thus the general properties of matter, and the
general laws of the adlions of bodies on each other, be¬
come gradually matter of obfervation and refleftion $
and the praftical mechanic will be frequently improving
his tools and machines. The general aim is to produce
a greater quantity of work by the fame exertion. The
attempts to improvement will be aukward, and frequent¬
ly unfuccefsful. When a man finds, that by increafing
the length of his lever he increafes his power of over¬
coming a refiftance, a fmall degree of curiofity is lufli-
cient to make him inquire in wffiat proportion his advan¬
tage increafes. When he finds that a double length
gives him a double energy, he will be furprifed and mor¬
tified to find, that at the end of the day he has not per¬
formed twice the quantity of work : but, after much ex¬
perience, he wall learn that every increafe of energy, by
means of a machine, is nearly compenfated by an in¬
creafe of time in the performance of his talk j and thus
one of the great and leading principles of pra&ical me¬
chanics was inculcated in a manner not to be forgotten,
and the practical mechanic was brought to fpeculate
about motion and force, and by gradual and eafy fteps
the general laws of fimple motions -were eftabliftied.
It is evident that thefe fpeculations cannot be carried
on, nor any confiderable knowledge acquired, without
fome acquaintance with the art of meafurement: and
4
SICS.
the very queftions which the mechanic willies to folve, tntroduc-
prefuppofe fome advances in this art, which in procefs of, t‘or,'
time refined itfelf into mathematics, the moft perfedt of v -
all the fciences. All the phenomena of fenfible motion
afford employment to the mathematician. It is perform¬
ed in a double or triple time, through a double or triple
fpace, by a double or triple body, by the exertion of a
double or triple force, produces a double or triple effedl,
is more to the right or to the left, upwards or down¬
wards, &c. In Ihort, every affedlion of motion is an
objedl of mathematical difcufiion. Such a fcience muft
have appeared ere now in the form of an art, in confe-
quencfe of the mutual tranfadlions of men. Thefe among
an uncultivated people are chiefly in the way of barter.
If I want corn from a peafant, and have nothing to give
for it but the cloth which I have made, we muft fall on
foftie way of adjufting our terms in refpect of the quan¬
tity. We Ihould foon difcover that the length, and
breadth, and depth, of the box or bag, were equally
important; and it was not difficult to fee, that if any of
them were doubled or tripled, the quantity of grain
would be fo too j if two of them were doubled, the grain
would be quadrupled j and if all the three were doubled
the quantity of grain would be increafed eight times:
the fame thing would be obferved with refpeft to my
cloth. By fuch tranfadlions as thefe, a few of the pro¬
perties of plane and folid numbers and figures would be¬
come known, and the operations of multiplication and
divifion, wdiere arithmetic is combined with geometry :
and daily obfervation Ihows us, that the more abftrufe
properties of number and figure, which to the generality
of mankind are fo infignificant, lay hold on the fancy of
fome individuals with fuch force, as to abftraA them
from every other intelleftual entertainment, and are ftu-
died with a keennefs and perfeverance almoft unequalled
in any other walk of fcience. To moft men the per¬
formance of a machine is a more attraflive objeft than
the properties of a figure, and the property of a figure
more entertaining than that of a number ; but the fa£l
feems to have been otherwife. Before Pythagoras had
invented the theorem that bears his name (fee Philoso¬
phy, N° 15. and note h), and which is among the firfl:
elements of geometry, he had reformed the Grecian mu-
lic by the addition of a note to their fcale, and this addi¬
tion proceeds on a very refined fpeculation on the pro¬
perties of numbers; fo that among the Greeks arithme¬
tic muft have made confiderable progrefs, while geome¬
try was yet in its cradle : and we know to what aftonilh-
ing length they profecuted the fcience of pure geometry,
while their knowledge of mechanical principles was al¬
moft nothing. Alfo the Arabs hardly made any addi¬
tion to the geometry of the Greeks, if they did not ra¬
ther almoft completely forget it; whilft they improved
their arithmetic into algebra, the moft refined and ab-
llrafted branch of human knowledge. There is fuch a
diftance, in point of fimplicity, between pure mathema¬
tics and the mort elementary mechanics, that the former
continued to make rapid fteps to improvement in more
modern times, while the latter languilhed in its infancy,
and hardly deferved the name of fcience till very lately,
when the great demand for it, by the increafe and im¬
provement in manufadlures, both interefted many in the
ftudy, and facilitated its progrefs, by the multitude of
machines which were contriving on all hands by the
manufa&urers and artifans : and even at prefent it muft
be
*
PHYSICS.
4°
The con
nedling
Introdtic- be acknowledged, that it is to them that we are indebted
lion. for almoft every new invention in mechanics, and that
v the fpeculatift feldom has done more than improve the
invention, by exhibiting its principles, and thus enabling
the artift: to correct its imperfeflions; and now fcience
and art go hand in hand, mutually giving and receiving
affiftance. The demands of the navigator for mathema-
4ical and aftronomical knowledge have dignified thefe
fciences •, and they are no longer the means of elegant
amufemcnt alone, but merit the munificence of princes,
who have erefted obfervatories, and furnifhed voyages
of difcovery, where the mathematical fciences are at the
fame time cherilhed and applied to the molt important
purpofes.
This Ihort Iketch of what may be called the natural
hi/lory of physicalfciences will not, we hope, be thought
improper or unprofitable. It tends to confirm an afl'er-
tion often alluded to, that the profecution of the ftudy
o 1 nature will be more fuccefsful, if we imitate her mode
of proceeding, and divide the labour. It will be ftill
further confirmed by attending to the fcientific differ¬
ence of the phenomena, which marks out a different
mode of proceeding, and a difference in the knowledge
which wre fhall ultimately acquire, after our moll fuc-
cefsfnl refearches.
In both claffes of phenomena already diftinguifhed
(N° 6.) we muff grant, that the principle which con-
principle of nefts the pairs of concomitant events, rendering the one
concomi- the infeparable companion of the other, is totally un-
tant events known t0 US) becaufe it is not the immediate obje& of
unknown. our perception.
41 But in the phenomena of the firft clafs, we fee the
In the firft immediate exertion of this principle, whatever it may be 5
C|rer’ tlnT" WC C3n °^^erve t^ie exerti°n with accuracy j w7e can de¬
exertion of teiTnine its kind and degree, which are the figns and
this prin- meafures of the kind and degree of the unperceived
caufe. This exertion, being always fome modification
of motion, allows us to call in the aid of mathematical
knowledge, and thus to afcertain with the precifion pe¬
culiar to that fcience the energy of the caufe, judging of
the tendency and quantity by the tendency and the
quantity of the obferved effeft.
But in the fecond clafs of phenomena the cafe is very
the fecond: ^fferent- the operations of chemiftry, for inftance,
the immediate exertion of the caufe is not perceived : all
that we obferve is the affemblage of particles which ob¬
tains before mixture, and that which takes place when
it is completed, and which we confider as its refult.
The procedure of nature in producing the change is un-
feen and unknown. The fteps are hid from our obfer-
vation. We are not only ignorant of the caufe which
determines one particle of our food to become a part of
our body while others are reje&ed, but we do not fee
the operation. We are not only ignorant of the caufe
which determines a particle of vitriolic acid to quit the
folfil alkali with which it is united in Glauber fait, and
to attach itfelf to a particle of magnefia already united
with the muriatic acid, which alfo quits it to unite writh
the alkali, but we do not fee the operation. The par¬
ticles and their motions are not the objects of our fenfes 5
and all that we fee is the Epfom fait and common fait
feparated from the water in which we had formerly dif-
folved the fal mirabile and the muriated magnefia. The
motions, which are the immediate effects of the changing
caufes, and therefore their only indications, ch^raBerif-
Vol. XVI. Part II.
42.S
ciple may
be accu¬
rately ob¬
ferved,
42
but not in
tics, and meafures, fitted to fhow their nature, are hid Introduc-
from our view. t‘on-
Our knowledge therefore of thefe phenomena mult be ' ^ '
lefs perfeft than that of the phenomena of the former And therc-
clafs 5 and we muft here content ourfelves with the dif- fore the
covery of more remote relations and remote caufes, and phenome-
with our ignorance of the very powers of nature by f.3
which thefe changes are brought about, and which are are ieis un-
cognofcible only by their immediate effe&s, viz. the mo-derftood.
tions which they produce unfeen. The knowdedge
which wre do really acquire is fomewhat fimilar to what
the mechanical philofopher has acquired when he has
difcovered, by many experiments and invelligations, that
magnets attraft each other by their diflimilar poles,
and repel each other by their fimilar poles, and do not
a£t at all on any bodies but loadftones and iron. Here
wre leave undifcovered all that is moll curious in the phe¬
nomenon, viz. how thefe attra£lions and repulfions are
produced ; and even here the magnetical philolbpher
has the advantage of feeing the agents and the opera-
tion. >
But philofophers attending to this circumftance, Though
that, even in thefe cafes, the changes are produced by ^,rne phita*
motions, or confift in motions, liowevei unperceived h^_ers
thefe may be, have concluded, that the laws according tempted
to which nature operates in producing thefe changes to explain
are fimilar to the laws which regulate her operations in h m by
the fenfible ablions of bodies, or are included in them ;the
and that the motions, though unfeen, and the moving'n'ot^.
forces, are perfeblly fimilar. They have therefore em- *
ployed fimilar modes of inveftigation, applying the laws
of impulfe, and calling in the aid of mathematical know¬
ledge.
Of this we have many examples in the waitings of
Dr Freind, Keil, Bernouilli, Hellham, Boerhaave, Hart¬
ley, and others, who have delivered theories of fermen¬
tation, folution, precipitation, cryftallization, nutrition,
fecretion, mufcular aftion, nay even of fenfation and
intelligence, founded, as they think, on the laws of mo¬
tion, and illuflrated and fupported by mathematical rea-
foning. Lord Bacon himfelf, that careful and fagaci-
ous dillinguilher of intelle&ual operations, has gone in¬
to the fame track in his explanation of the phenomena
of fire and combufiion : and Sir Ifaac Newton has
made feveral attempts of the fame kind, although with
peculiarities which always charatterife his difcuflions,
and make them very different from thofe of an inferior
clafs.
But the fuccefs of thefe philofophers has hitherto been but their
very difcouraging: indeed they had no title to expert attempts
any for their whole trains of reafoning have proceededtiave ^eeR
on analogies which were not obferved, but affumed or^]luccefs"
fuppofed without any authority. There is not that fimi- U ’
larity in the phenomenon, or in the vifible effeft, which
is abfolutely neceffary for a fuccefsful reafoning by ana¬
logy. We do not obferve any local motion, any change
of f ace, which alone enables us ft> reafon mathemati¬
cally on the fubjeft. And to make the cafe defperate,
this ill-founded analogy has been mixed with hypothefes
completely gratuitous. Certain forms have been alfign-
ed to the particles, and certain modes of aftion have
been laid down for them, for whofe reality wf have not
the leaf! argument or indication : and to complete the
matter, thefe fancied forms and laws of a£lion have been
fuch as are either feif-contradictory and ineonfiftent, or
3 H they
P H Y S I G S.
45
The advan
tage de¬
rived in
thefe fpe~
culation?
from ma¬
thematical
phiiolophy.
they have been fuch as, if allowed to aft in a way ana¬
logous to what we obferve in the fennble motions of bo¬
dies, would produce effefts totally different from thofe
which are obferved. Thefe atomical theories, as they
are called, tranfgrefs every rule of philofophical difcul-
lion, and even the belt of them are little better than
trilling amufements. By far the greateft part of them
only ferve 10 raife a fmile of pity and contempt in every
perfon at all acquainted with mechanical philofophy.
Whenever we fee an author attempting to expbm thefe
hidden operations of nature by invifible fluids, by aethers,
by collifrons, and vibrations, and particularly if we fee
him in reducing mathematical reafonings into fuch ex¬
planations—the bed; thing we can do is to fhut the Book,
and take to fame other fubjeft. That we may not be
thought to fpeak prefumptuouily on this occafion, we
only beg leave to remind our readers, that the united
knowledge of the moft eminent mathematicians of Eu¬
rope has not yet been able to give any thing more than
an approximation to the folution of the problem 01 three
bodies $ that is, to determine with accuracy the motions
of three particles of matter afting on each other in the
limp left of all poffible manners, viz. by forces varying
as the fquares of the diftances inverfely : and the vibra¬
tions of elaflic bodies, of any but the very fimpleft pof¬
fible forms, are to this day beyond the reach of invefti-
gation. WhaJ then (hould be our expeftations in cafes
where millions of particles are afting at once, of forms
unobferved, and with forces unknown, and where the
objeft is not a determination of an average refult of ma¬
ny, where the precife fate of an individual particle need
not be known, but where it is this very precife ftate . of
each fugle particle that wre want to know ? What can
it be but uncertainty and miftake ?
. Notwithftanding thefe difeouraging cireumftances, we
mull obferve that this kind of inquiry has greatly im¬
proved ot late years, along 'with the improvement and
extenfon of mathematical philofophy, and fnce phiio-
fophers have given over their incetTant attempts to ex¬
plain every thing by impulfe } and we need not defpair
of making fill farther advances, if w*e will content our-
felves with going no farther than Newton has done in
his explanation of the planetary motions. He has im¬
mortalized his own name, and has added immenfely to
our flock of ufeful knowledge : yet he has flopped thort
at the difeovery of the faft of univerfal gravitation; and
all who have endeavoured to explain or account tor this
faft have only expofed themfelves to pity. We may per¬
haps be one day able to demonflrate from the phenome¬
na that the particles of matter have certain mutual ten¬
dencies to or from each other, exerted according to fix¬
ed or invaried rules } and from thefe tendencies we may
be able to explain many other phenomena, and predift
the confequences, wTith as much certainty and evidence
as an aflronomer calculates a future eclipfe. This would
he a great acquxfition, and perhaps more is impefhble :
and the road to this has been hinted by Sir Ifaac New¬
ton, who has expreffed his fufpicion, that as the great
movements of the folar fyftem are regulated by univerfal
gravitation, fo the mutual aftions of the particles of mat¬
ter are produced and regulated by tendencies of a fimilar
kind, equally but not more inexplicable, and of which
the laws of aftion are to be difeovered by as careful an
attention to the phenomena, and by the fame patient
thinking, which he has employed on the planetary mo¬
tions. And a beautiful introduction to this new and al- Introduc-
moft unbounded field of inquiry has been given us by 11 n-
the celebrated Abbe Bofcovich, in his Theory of Natu-
ral Philofophy* where he has drown how fuch mutual
tendencies, futilar in every ultimate particle of matter,
and modified by conditions that are highly probable,
nay almotf demonftrable, will not only produce ihe fen-
fi'ole forms of folidity, hardnefs, elafticity, ductility, flui¬
dity, and vapour, under an inconceivable «»nely of mb-
ordinale appearances, and the obierved laws of fenfible
motion, but will go dir to explain the phenomena of fu¬
sion, congelation, iolution, crvilaiiization, &c. &c. &c.
both in chemiftry and puyfiology. We earneftly recom¬
mend this work to the perufal of all who wifh to obtain
a diltinft notion of the internal conflitution of natural
bodies, and of the way in which the uniting forces pro¬
duce their ultimate and fenfible effefts. Any -perfon,
poffeffed of a moderate fhare of mathematical knowledge,
will be convinced that the procefs of nature is not very
different from what he deferibes ; and that much of what
wc obferve muff happen as he fays, even although the '
ultimate atoms of matter are not inextended mathema¬
tical points, accompanied with attrafting and repelling
forces. 47-
But we have many fteps to make before we begin this Our igno-
ftudy : Nature opens to us an immenfe volume ; and werai,c^ lf
doubt not that our pofterity will long find employment^
in the perufal, even though advancing with the eager- h]c jr;tlLa c
nefs and fuccefs of the laft century. We have not yet ot know-
arrived at the threfhold in many parts of this refearch : 1 cke a-
In many parts of chemiftry, for infiance, ne are as yet^T^
uncertain with refpeft to the phenomena themfelves,
which are to be the fubjefts of this difeuffion. The
compofition of bodies muff be fully underftood before we
begin to fpeak of the forces which unite their particles,
or {peculate about their modes of aftion. As long as
water was confidered as an element, we were ignorant
of the forces inherent in its particles ; we are perhaps
Hill ignorant of this \ but we now know that they are
extremely different from what we formerly fuppofed them
to be. It is but in a very few, if in any, cafes of che¬
mical combination, that we even know what are the in¬
gredients : till we know this, it is too foon to fpeculate
about their mode of union. Our ignorance in the real
events in the animal and vegetable economy is ftill
greater. Our firft talk, therefore is to proceed, as we
are now doing, in the accurate examination and claffifi-
cation of the phenomena themfelves \ and, without at¬
tempting to bring them within the pale of mathematical
philofophy, by attempting what are called mechanical
explanations, let us give up the confideration of thefe
hidden operations, and augment to the utmoft our lift
of fecondary laws of vifible but remote conneftions. All
the mechanical {peculations of the honourable Robert
Boyle about the fenfible qualities of things are now for¬
gotten ; but his chemical experiments preferve all their
value, and are frequently referred to. The fame may
be faid of the fagacious Dr Hales,' whofe fanciful notions
of internal conflifts, and collifions, and vibrations, de¬
rogate nothing from the value of the curious fafts which
he has eftablifhed both in the animal and vegetable eco- 48
The parti-
vn. n. . 1 - .1 1 j cutar divi-
This dlftmftion m the nature of the phenomena, and -or|S of
this difference in the nature of the knowledge which phyfical
is to be acquired, and the means which are to be em-icience in
ployed Britain.
PHYSICS.
427
Introtluc-
ployed for the fuccefsful profecution of thefe two branch¬
es of general phyfics, has occafioned a ilill farther re-
ftriftion (at leaft in Britain) of the term NATURAL phi¬
losophy. It is particularly applied to the ftudy of the
phenomena of the firft clafs, while thofe of tlie fecond
have produced the fciences of Chemistry and physio¬
logy.
Natural philofophy and chemiftry have generally
been made particular inftitutions in our feminaries of
learning, but phyfiology has more commonly been
taught in conjunction wil.h anatomy, medicine, and bo¬
tany.
The phenomena of the firft ciafs have been ufually
Called MECHANICAL, in order to diftinguilh them from
thofe obferved in the operations of chemiftry, and in
the animal and vegetable economy •, and the explanations
which have been attempted of fome of the laft, by ap¬
plying the laws obferved in the phenomena of the firft
elafs, have been called ?nechanicalexplanations.
As this firft clafs is evidently but a part of gene¬
ral phyfics, there is fome impropriety in giving the
name natural philofophy to a courfe of do&rines which
is confined to thefe alone. Indeed at the firft inftitu-
tion of univerfities, the ledlures given in the Schola
Pkyjtca were much more extenfive, comprehending al-
molt all the phenomena of the material world : but as
all arts and iciences have improved moft where the la¬
bour has be'en moft divided, it was found more condu¬
cive to the advancement of knowledge that feparate
inftitutions fhould be founded for the ftudies of natu¬
ral hiftory, chemiftry, phyfiology, &c.j and thus the
phenomena, purely mechanical, and a few others in
magnetifm, electricity, and optics, which either were
fufceotible of mathematical treatment, or had little
connection w ith the ftudies of chemiftry and phyfiology,
were left to the care of the profeffor of natural philo-
ibphy.
As the terms chemiftry and phyfology have been ap¬
plied to two very important branches of general phy¬
fics, we think that a more fpecific or chara&eriftic
name might be appropriated to the other, and that
it might very properly be termed MECHANICAL philo¬
sophy.
It only remains to make a few’’ obfervations on the
diftinftive means of profecuting thefe ftudies with fuc-
cefs, and to point out fome of the advantages which
may reafonably be expecied from a careful profecution
. of them : and as the fecond branch has been fully treated
under the fcveral articles of Chemistry,- Physiology,
&cc. we {hall confine ourfelves to what is ufually called
NATURAL PHILOSOPHY.
49
Mechanical MECHANICAL PHILOSOPHY may, in conformity with
phiiofophy {Jie foregoing obfervations, be defined, “ the ftudy of the
ancfbs’ knfible motions of the bodies of the univerfe, and of their
principles a&ions producing fenfible motions, with the view to dif-
explained. cover their caufes, to explain fubordinate phenomena,
and to improve art.”
The principle upon which all philofophical difcuffion
proceeds is, that every change ’which we ohferve in the
condition of things is confdered by us as an ejfedl, indi¬
cating the agency, charaBerifng the hind, and meafuring
tie degree, of its caufe.
In the language of mechanical philofophy, the caufe
of any change of motion is caaed a moving or chan-Mechanical
J ^ ° Philolophy.
gmg FORCE. 1 .
The difquifitions of natural philofophy muft therefore
begin with the confideration of motion, carefully noti¬
cing every affeClion or quality of it, fo as to eftablifh
marks and meafures of every change of which it is fuf-
ceptible; for thefe are the only marks and meafures of
the changing forces. This being done, it only remains
to apply them to the motions wdiich we obferve in the
univerfe. r 5°
From the general principle of philofophical difeuftion !j,e law9
already mentioned, there flow directly two axioms.
1. Every body perfeveres in a fate of ref, or of uniform ai,piu ation.
reElilineal motion, unlefs ajfeEled by forne movmgforce.
2. Every change of motion is in the diredhon and in the
degree of the force imprejfed.
Thefe are ufually called the LAWS of motion. They
are more properly law’s of human judgment, with refpeft
to motion. Perhaps they are neceffary truths, unlefs it
be alleged that the general principle, of which they are
neceffary confequences, is itfelf a contingent though uni-
verfal truth.
By thefe two axioms, applied in abf radio to every
variety of motion, yve eftabliih a fyftem of general doc¬
trines concerning motions, according as they are fimple
or compounded, accelerated, retarded, rectilineal, cur-
vilineal, in fingle bodies, or in fyftems of conneCted bo¬
dies and we obtain correfponding charaCteriftics and
meafures of accelerating or retarding forces, centripetal
or centrifugal, fimple or compound.
We have an illuftrious example of this abftraft fyftem
of motion and moving forces in the firft: book of Sir Ifaac
Newtbn’s Mathematical Principles of Natural Philofophy.
Euler’s Mechanic a fvie Scientia Mot us, Herman’s Pho-
ronomia fve de Viribus Corporum, and D’Alembert’s
Traite de Dynamique, are alfo excellent works of the
fame kind. In this abftract fyftem no regard is paid to
the cafual differences of moving forces, or the fources
from which they arife. It is enough to characterife a
double accelerating force, for inftance, that it produces
a double acceleration. It may be a weight, a ftream of
water, the preffure of a man •, and the force, of which it
is faid to be double, may be the attraction of a magnet,
a current of air, or the aftion of a fpring.
Having eftablithed thefe general doCtrines, the phi-
lofopher now applies them to the general phenomena of
the univerfe, in order to difeover the nature of the forces
which really exilt, and the laxvs by which their opera¬
tions are regulated, and to explain interefting but fubor¬
dinate phenomena. This is the chief bufinefs of the me¬
chanical philofopher ; and it may with fome propriety
be called the mechanical hifory o f nature. cT
Some method muft be followed in this hiftory of me- Of the ar-
chanical nature The phenomena muft be claffed by rangement
means of their refemblances, which infer a refemblance j n|e*
in their caufes, and thefe clafles muft be arranged ac-nhewime-
cording to fome principle. We have feen no method'na of the
which appears to us lefs exceptionable than the follow- univerfe.
in?\ . . . . 5*
The principle of arrangement is the generality of the The eene-
phenomena ; and the propriety of adopting this princi- ! a !ty
pie, arifes from the probability which it gives us of more-^^ri1^
readily difoovermg the moft general actuating forces, ^.jncipie
whefe agency is implicated in all other phenomena of >t arrange-
3 H 2 lefs ‘lent*
428
Mechanicallefs extent; and therefore fhould be previoufly difeuffed,
1 liilohinh}. we jYjay detect the diferiminating circumftances
which ferve to charadterife the fubordinale phenomena,
and are thus the marks of the diftinguithing and inferior
natural powers.
The laws of ^'^e m0^ general of all phenomena is the curvilineal
motion are motion of bodies in free fpace ; it is obferved through
firft applied the whole extent of the folar fyftem.
rnic;f|IOh°~ The mechanical hiftory of nature begins therefore
inomena. with aftronomy. Here, from the general phenomena
of the planetary motions, is evinced the faB of the mu¬
tual dededlion of every body towards every other body,
and this in the inverfe proportion of the fquares of the
ditlance, and the diredl proportion of the quantity of
■matter. This is the fa£l of universal gravitation,
indicating the agency, and meafuring the intentity, of
the univerfal force of mutual gravity.
Having eftablithed this as an univerfal fa£t, the na¬
tural philofopher proceeds to point out all the particular
fadfs which are comprehended under it, and whofe pecu¬
liarities charafterife the different movements of the folar
fyftem. That is, in the language of philofophy, he gives
a theory or explanation of the fubordinate phenomena ;
the elliptical motions of the planets and comets, their
mutual difturbances; the lunar irregularities; the oblate
figure of the planets; the nutation of the earth’s axis ;
the preceffion of the equinoxes; and the phenomena of
the tides and trade winds : and he concludes with the
theory of the parabolic motion of bodies projected on
the furface of this globe, and the motion of pendu¬
lums.
As he goes along, he takes notice of the applications
which may be made to the arts of life of the various
doftrines which are fucceflivelyeftablifhed ; fuch as chro¬
nology, aftronomical calculation, dialling, navigation,
gunnery, and the meafuring of time.
If a fquare parcel of fand be lying on the table, and
The nature.finger be applied to any part of it to pufh it along
^0^ravita‘ the table, that part is removed where you will, but the
PHYSICS.
54
The appli¬
cation of
this fei-
ence to the
arts of
life.
55
5*
and of co-
Jielion.
57
Mode of
in ve (liga¬
ting the
laws of co-
hefion.
reft remains in its place ; but if it is a piece of fand-ftone
of the fame materials and fliape, and the finger is applied
as before, the whole is moved ; the other parts accom¬
pany the part impelled by the finger in all its motions.
From the moon’s accompanying the earth in all its
motions round the fun, we infer a moving force which
conne&s the moon and earth. In like manner, we muft
conclude that a moving force connetfts the particles of
the ftone ; for we give the name force to every thing
which produces motion : We call it the force of cohe¬
sion ; a term which, like gravitation, expreffes merely
a fa6L
This feems to be the next phenomenon of the univerfe
in point of extent.
Having, from the general phenomenon, eftabliflied
the exiftence of this force, the philofopher proceeds to
afeertain the laws by which its exertions are regulated;
which is the afeertaining its diftinftive nature and pro¬
perties. This he does in the fame wTay that he afeer-
tained the nature of planetary gravitation, vi%. by ob-
ferving more particularly the various phenomena.
Here is opened a moft extenfive and varied field of
obfervation, in which it muft be acknowledged that very
little regular and marked progrefs has been made. The
variety in the phenomena, and the confequent variety in
the nature of the connecting forces, appear as yet in¬
conceivably great; and there feems little probability ofMechame*!
our being able to deteeft in them all any famenefs, com- PMofophy.
bined with the other diftinguiftiing circumftances, as we    
have done in the cafe of gravity. Yet we ftioulft not
defpair. Bofcovich has fhown, in the moft unexcep¬
tionable manner, that although we ftiall fuppofe that
every atom of matter is endued with a perfe&ly fimilar
force, aiding in a certafti determined ratio of the fmall
and imperceptibfe diftances at which the particles of
matter are arranged with refpedl to each other, the ex¬
ternal or fenfible appearances may, and muft, have all
that variety which we obferve. He alfo fhows very dif-
tindlly how, from the operation of this force, muft arife
fome of the moft general and important phenomena
which charadterife the different forms of tangible bodies.
We obferve the chief varieties of the adtion of this
corpuscular force on the bodies which we denomi¬
nate hard, /of, folid, fluid, vaporous, brittle, duBile,
elaflic. We fee inftances where the parts of bodies avoid
each other, and require external force to keep them to¬
gether, or at certain fmall diftances from each other.
This is familiar in air, vapours, and all compreflible and
elaftic bodies.
This is evidently a moft curious and interefting fub-
jedl of inveftigation. On the nature and adlion of thefe
corpufcular forces depends the ftrength or firmnefs of
folids, their elafticity, their power of communicating
motion, the preffure, and motion, and impulfe of fluids ;
nay, on the fame adlions depend all the chemical and
phyfiological phenomena of expanfion, fufion, congela¬
tion, vaporifation, condenfation, folution, precipitation,
abforption, fecretion, fermentation, and animal and ve¬
getable concodlion and afllmilation.
Out of this immenfe ftore of phenomena, this inex-
hauftible fund of employment for our powers of invef¬
tigation, the natural philofopher felefts thofe which lead
diredlly to the production or modification of fenfible mo¬
tion.
He will therefore confider,
l. The communication of motion among detached and H15 pro-
free bodies, eftabliftiing the laws of impulfe or collifion. du<^lon
This has always been confidered as the elementary doc-Jn^r'ife^has
trine of mechanical philofophy, and as the moft familiarbeen
'fad obferved in the material world; and in all ages thought the
philofophers have been anxious to reduce all aftions offf'?^ famt*
bodies on each other to impulfe, and have never thought
a phenomenon completely explained or accounted for *
till it has been ftiown to be a cafe of impulfe. This it
is which has given rife to the hypothefes of vortices,
ethers, magnetic and eleftric fluids, animal fpirits, and
a multitude of fancied intermediums between the fenfible
maffes of matter, which are laid in common language
to aft on each other. A heavy body is fuppofed to fall,
becaufe it is impelled by a ftream of an invifible fluid
moving according to certain conditions fuited to the cafe.
The filings of iron are fuppofed to be arranged round a
magnet, by means of a ftream of magnetic fluid iifuing
from one pole, circulating perpetually round the magnet,
and entering at the other pole, in the fame manner as
we obferve the flote-grafs arranged by the current of a
brook. _ 59
But the philofopher who has begun the mechanical But this
ftudy of nature by the abftraft doftrines of dynamics,0I^n^n is
and made its firft application to the celeftial phenome-^fry ^,ue^‘
na, and who has attended carefully to the many ana- 1 na e‘
logics.
PHYSICS.
429
Mechanical logics between the phenomena of gravitation and cohe-
Philofophy. flori} will be at leaft ready to entertain very different
notions of this matter. He will be fo far from think¬
ing that the production of motion by impulfe is the
molt familiar faCt in nature, that he will acknowledge
it to be comparatively very rare ; nay, there are fome
appearances in the faCts, which are ufually considered
as inftances of impulffon, which.will lead him to doubt,
and almoft to deny, that there has ever been obferved an
inltance of one body putting another in motion by com¬
ing into abfolute contaft with it, and itriking it j and
he will be difpofed to think that the production of mo¬
tion in this cafe is precifely Similar to what we obferve
when we gently pulh one floating magnet towards ano-
Motion ther, with their fimilar poles fronting each other. There
feems to be will be the fame production of motion in the one and di-
produced minution of it in the other, and the fame uniform mo-
from the ^ tion of the common centre of gravity: and, in this cafe
^l^n'and ^ magnets, he fees completely the neceflity of a law
reaction!11 °f motion, which is not an axiom, but is obferved through
the whole of nature, and which receives no explanation
from any hypothefis of an intervening fluid, but is even
totally inconffftent with them. We mean, “ that every
aCtion of one body on another is accompanied by an
equal and oppofite aCtion of that other on the firff.”
This is ufually called the equality of aclion and reaBion:
it is not intuitive, but it is univerfal 5 and it is a necef-
fary confequence- of the perfeCt fimilarity of the corpuf-
cular forces of the fame kinds of matter. This general
faCt, unaccountable on the hypotheffs of impelling fluids,
is confidered in the planetary motions as the unequivocal
indication of the fameners of that gravity which regulates
-them all. The rules of good reafoning fliould make us
draw the fame conclufion here, that the particles of tan¬
gible matter are connected by equal and mutual forces,
which are the immediate caufes of all their fenflble ac¬
tions, and that thefe forces, like gravitation, vary with
every change of diftance and fituation.
The laws of collifion and impulfion being now7 efta-
bliflied, either as original faCts or as confequences of the
agency of equal and mutual forces which conned the
particles of matter, the philofopher confiders,
2. The produdion of motion by the intervention of
folid bodies, where, by reafon of the cohefion of mat¬
ter, fome of the motions are neceflarily confined to
certain determinate paths or diredions. This is the
cafe in all motions round fixed points or axes, or along
planes or curves which are oblique to the adion of the
forces.
This part of the ftudy contains the theory of machines,
pointing out the principles on which their energy de¬
pends, and confequently furnifhing maxims for their con-
ftrudion and improvement. But thefe obfervations do
not complete the difeuflion of the mechanifm of folid bo¬
dies : they are not only folid and inert, but they are al-
fo heavy ; therefore the adion of gravity muft be com¬
bined with the confeqwences of folidity. This w7ill lead
to difeuflions about the centre of gravity, the theory and
conftrudion of arches and roofs, the principles of liabili¬
ty and equilibrium, the attitudes of animals, and many
particulars of this kind.
3. The philofopher vrill now turn his attention to
61
Of motion
as it re-
fpects the
theory of
machines,
&c.
62
Mecha¬
nics.
63
The nature
and defini- another form, in which tangible matter exhibits many
tion of flui- interefting phenomena, vh. fluidity. The firft thing
dity. to be attended to here is, What is that particular form of
ex fence ? What is the precife phenomenon which cha- Mechanical
raderifes fluidity ? What is the definition of a fluid ? ‘Tilofophy.^
This is by no mfeans an eafy queition, and conliderable
objedions may be Hated again!! any definition that has
been given of it. Sir Ifaac Newton fays, that a fuid
is a body whofe particles yield to thefmallefl impreJJiony
and by fo yielding are eafdy moved among themfelves. It
may be doubted w7hether this be fufhciently precife j
what is meant by the fmallcfl imprefjion ? and w7hat is
eafily moving ? Is there any precife degree of impreflion
to which they do not yield \ and do they oppofe any re¬
finance to motion ? And a ilronger objedion may be
made : It is not clear that a body fo conflituted will
exhibit all the appearances which a body acknowdedged
to be fluid does really exhibit. Euler offers fome very
plaufible reafons for doubting whether it will account for
the horizontal furface, and the complete propagation of
preffure through the fluid in every diredion \ and there¬
fore prefers feleding this lajl phenomenon, the propaga¬
tion of preffure qudqua-verfum, as the charaderiftic of
fluidity, becaufe a body having this conftitution (on
whatever circumltances it may depend) will have every
other obferved property of a fluid. But this definition
is hardly fimple or perfpicuous enough *, and we think
that the objedions again!! Newton’s more fimple and in¬
telligible definition are not unanfwerable. Bofcovich
defines a fluid to be, a body whofe particles exert the
fame mutualforces in all directions ; and (hows, that fuch
particles mull be indifferent, as to any pofition, with
refped to each other. If no external force ad on them,,
they wall remain in every pofition, and w ill have no ten¬
dency to arrange themfelves in one pofition rather than
another 5 differing in this refped from the particles of
folid, or foft, or vifeid bodies j wdiich require fome force
to change their refpedive pofitions, and wrhich recover
theie pofitions again w7hen but gently difturbed. He il-
luftrates this dillindion very beautifully, by comparing a
parcel of balls thrown on quickfilver, and attrading each ,
other, with a parcel of magnets in the fame fituation. The
balls will flick together, but in any pojition; whereas the
magnets will ahvays affed a particular arrangement. ^
When the charaderiflic phenomenon of fluidity has of the pref-
been feleded, the philofopher proceeds to combine this fare and
property wdth gravity, and eftabliflies the dodrines ofe9ufl1.bnum*
hydrostatics, or of the preffure and equilibrium of°^ fu^s’ or
heavy fluids, the propagation of this preffure in every t^Si
diredion j and demonftrates the horizontality of furface
affumed by all perfed fluids.
Thefe dodrines and principles enable us to determine
feveral very interefting circumftances refpeding the
mutual preffure of folids and fluids on each other; the
preflures exerted on the bottoms and fides of veffels •, the
fupport and whole mechanifm of floating bodies, &c.
He then confiders how fluids will move when their Of the mo*,
equilibrium of preffure is deftroyed ; and eftablifhes the h011
dodrines of hydraulics, containing all the modifica-^u^s’ °.r
tions of this motion, arifing from the form of the veffels, 1 riUl IC?*
or from the intenfity or diredicn of the preffure which
occafions it. And this fubjed is completed by the con-
fideration of the refiftance which fluids oppofe to the
motion of folid bodies through them, and their impulfe
on bodies oppofed to their adion.
Thefe are very important matters, being the founda
tions of many mechanical arts, and furnifhing us writh
fome of our moft convenient and efficacious powers for
impel..
430 r n v
Mecha:'.!cal impelling maclimes. They are alfo of very difficult dif-
Flnlarophy. cu{iion> an(j are by notmeans completely invelligated or
66 eftablifhed. Much remains yet to be done both for per-
Th? im- fefting the theories and for improving the arts which de-
portance pend on them.
and difficul- jj. js evident, that on thefe do&rines depend the
branch's of knowledge of the motions of rivers and of weaves •, the
fcience. buoyancy, equilibrium, and liability of Ihips; the mo¬
tion of fliips through the waters ; the aftion of the winds
on the fails j and the wdiole arts of marine conllrudlion
67 and feamanlhip.
The nature There is another general form of tangible matter
and defini- wbich exhibits very different phenomena, which are alfo
vapour extremely interefting ■, we mean that of VAPOUR. A
vapour is a fluid ; and all the vapours that we know are
heavy fluids : they are therefore fubje£l to all the laws
of preflure and impulfe, wThich have been confidered
under the articles Hydrodynamics. But they are
fufceptible of great compreflion by the a£iion of ex¬
ternal forces, and expand again when thele forces are
removed. In confequence of this compreflion and ex-
panflon, the general phenomena of fluidity receive great
and important modifications j and this clafs of fluids re¬
quires a particular conlideration. As air is a familiar
inftance, this branch of mechanical philofophy has been
6g called PNEUMATICS.
The doc- Under this head we confider the preffure of the at-
trine of air, mofphere, and its effe6ls, both on folid and fluid bodies,
or pneuma- jq produces the rife of waters or other fluids in pumps
tlcs’ and fyphons, and gives us the theory of their conftruc-
tion : it explains many curious phenomena of nature,
fuch as the motions in the atmofphere, and their con¬
nexion with the preffure of the air, and its effeX on the
barometer or weather-glafs. Air, when in motion, is
called wind; and it may be employed to impel bodies.
The theory of its aXion, and of its refiftance to moving
bodies, are therefore to be confidered in this place.
But befides their motions of progreflion, &c. fuch as
we obferve in winds, compreflible or elaflic fluids are fuf¬
ceptible of what may be termed internal motion ; a kind
of undulation, where the contiguous parts are thrown
into tremulous vibrations, in which they are alternately
condenfed and rarefied; and thefe undulations are propa¬
gated along the mafsof elaftic fluid, much in the fame way
in which we obferve waves to fpread on the furface of
water. What makes this an interefting fubjeX of con-
fideration is, that thefe undulations are the more ordi¬
nary caufes of found. A trembling chord, or fpring,
or bell, agitates the air adjoining to it: theie agi¬
tations are propagated along the air, and by its in¬
tervention agitate the organ of hearing. The mechanifm
of thefe undulations has been much ftudied, and furnifhes
69 a very beautiful theory of mulical harmony.
Of the The philofopher examines the law of comprcffibility
■ compreffi- 0f ajr ancj other elaftic fluids ; and thus gets the knowr-
elafftc0 ledge of the conftitution of the atmofphere, and of the
fluids, and aXion of thofe fluids when employed to impel folid bo¬
lts eonfe- dies. Gunpowder contains an immenfe quantity of per-
quences. manently elaftic air, which may be fet at liberty by in¬
flammation. When this is done at the bottom of a piece
of ordnance, it will impel a ball along the barrel, and
difcharge it from th£ muzzle, in the fame way that an
arrow is impelled by a bow. And thus having difcovered
in what degree this air preffes in proportion to its expan-
fipa, we difcover its aXion on the ball through the vThole
2
3 I C S.
length of the piece, and the velocity which it will finally Mechanical
communicate to it. Here then is contained a theory of [',hl!oiHPhy^
artilleryand of mines.
Chemiftry teaches us, that moft bodies can be con- of the con¬
verted by fire into elaftic fluids, which can be employed verfion of
to aX on other bodies in the way of preffure or impuife.
Thus they come under the.review of the mechanical phi-
lofopher ; and they have become interefting by being em¬
ployed as moving forces in fome very powerful machines.
Thefe difcuflions will nearly exhauft all the general
mechanical phenomena. There remain fome which are
much more limited, but furnifh very curious and im-
_portant fubjeXs of inveftigation.
The phenomena exhibited between loadftones or mag- Of the phe-
nets and iron have long attraXed attention ; and the ufe nomen a of
to which the polarity of the loadftone has been applied, kadftone,
namely, the direXing the courfe of a fhip through the
pathlefs ocean, has rendered thefe phenomena extremely
interefting. They are fpecified by the term MAGNETISM.
Confiderable progrefs has been made in the arrangement
and generalization of them ; but we have by no means
been able hitherto to bring them all under one Ample
faX. The attention has been too much turned to the
difcovery of the ultimate caufe of magnetifm ; whereas
we fhould have rather employed our ingenuity in difcover-
ing all the general laws, in the fame manner as Kepler
and Newton did with refpeX to the celeftial phenomena,
without troubling themfelves with the caufe of gravita¬
tion. Dr Gilbert of Colchefter was the firft who con¬
fidered the magnetical phenomena in the truly philofo-
phical manner; and his treatife De Magnate may be
confidered as the firft and one of the moft perfeX fpeci-
mens of the Baconian or induXive logic. It is indeed
an excellent performance; and when wTe confider its date,
1580, it is a wonder. iEpinus’s Tentamen Tlieornc
Magnelifmi is a moft valuable work, and contains all the
knowledge which we have as yet of the fubjeX. ^
There is another clafs of mechanical phenomena which Of electri-
have a confiderable affinity with the magnetical; we '-a' phena-
mean the phenomena called eeectrical. Certain bo-mena*
dies, when rubbed or otherwife treated, attraX and repel
other bodies, and occafion a great variety of fenfible mo¬
tions in the neighbouring bodies. Philofophershave paid
much attention to thefe appearances of late years, and
eftablifhed many general larvs concerning them. But
we have not been more fuccefsful in bringing them all
under one faX, and thus eftabliftiing a complete theory
of them, than in the cafe of magnetifm. Franklin and
Aipinus are the authors who have been moft fuccefsful
in this refpeX. Dr Franklin in particular has acquired
great celebrity by his moft fagacious companfon of the
phenomena; which has enabled him to eftablifh a few
general lawrs, almoft as precife as thofe of Kepler, and
of equally extenfive influence. His difcovery too of the
identity of thunder and eleXricity has given an import¬
ance and dignity to the whole fubjeX. 73
There are many phenomena of eleXricity which can-Thef<j.are
not be called mechanical, and are of the moft curious chanicaT6"
and interefting kind. As thefe have little conneXion
with any of the other great branches of phyfical fcience,
they have generally been confidered in treatifes of natu¬
ral philofophy ; and along with inquiries into the origi-
•nal caufe of eleXricity in general, continue to engage
much of our attention.
The appearances which' are prefented to us by our
fenfe
PHYSICS.
vifion.
Mechanical fenfe of feeing form another clafs, Tvhich have always
fhilofophy- ljeen conhdered as making a branch of natural philo-
v~ fophy in all feminaries of learning. It does not, how-
Of the phe-ever, obvioufly appear, that they are mechanical phe¬
nomena of nomena. The intimate nature of light is Hill a fecret.
Fortunately it is not necefl'ary to be known to give us
a very perfedt theory of the chief phenomena. The
.general laws of optics are fo few, fo fimple, and fo
precife, that our theories are perhaps more perfect here
than in any other branch of phyiics; but thefe theories
are as yet far removed from the rank of primary fadfs.
Many unknown events happen before the phenomenon
comes under the. hands'of the .ordinary optician, fo as to
become the fubjefts of the fimple laws of rdlection and re-
J5,)tenJrdSti°n. It may eveu be doubted, and has been doubt¬
ed, whether the phenomena of optics are cafes of body
in motion; whether all the lines which the optician draws
It has been
thmbted
w heHwr
light is
corportah
Haw optic
as a p
mechanical
pliiiofophy.
are any thing but the direhtions along which certain qua¬
lities me exerted. The fide of a ball which is next the
candle may be bright and the other fide dark, juft as the
fide of a ball which is next the electrical globe is minus
and the other fide plus ; and alj this without any inter¬
vening medium. Apparition or vifibility may be a qua¬
lity of a body, depending on the proximity and pofition
of another body, without any thing between them, juit
as weight is •, and this quality may be cognizable by our
faculty of feeing alone, juit as the preffure of a heavy
body is by our teeling alone.
The firlt thing which made it probable that mechani-
came to be cal philofophy had any thing to do with the phenomena
coniidered^ 0p{JCSj was the difeovery of Mr Roemer, “ that ap-
as a p.i u parjtjon was not inftantaneous j” that feme time elapfed
between the illumination of a body and its being feen at
a diltance. He difeovered, that it was not till 40 mi¬
nutes after the fun illuminated one of Jupiter’s fatellites
that it was feen by. an inhabitant of this globe. If there¬
fore a fun were juft created, it would be 40 minutes be¬
fore Jupiter would be illuminated by him, and 200 be¬
fore the Georgian planet would be illuminated. Here
then is motion. It is therefore highly probable that
there is fomething moved j but it is ftilt doubted whe¬
ther this fomething, which we call LIGHT, is a matter
emitted from the fhining body, and moving with great
velocity, and a£fing on and affefted by other bodies, in
the various phenomena of optics, or whether it is a certain
Jlate of a medium which is thus propagated, as we fee
that v/aves are propagated along the furface of water, or
fonorous undulations through the mafs of air, while the
water or air itfelf is hardly moved out of its place. Ei¬
ther of thefe fuppofitions makes optics a legitimate branch
of mechanical philofophy ; and it is the pnilofopher’s bu-
finefs to examine both by the received laws of motion,
and fee which of them gives confequences which tally
with the phenomena. This has been done j and we ima¬
gine that a complete incompatibility has been demon-
ftrated between the confequences of the undulations of
an elaftic medium, and the phenomena of optics ; while
the confequences of the other or vulgar notion on this
fubject are perfectly confiftent with mechanical laws.
There are fome things in this hypothefis very far beyond
our power to conceive diftinftly ; but they are all fimi-
lar in this refpeft to many facts acknowledged by all 5
and there is no phenomenon that is inconfiftent with the
legitimate confequences of the hypothefis. This gives it
great probability 3 and this probability is confirmed by
77
The nature
of light is
itill unde¬
termined.
many chemical fa£ts, and by facts in the vegetable ecc- Mechaniial
nomy, which give ftrong and alinoft undeniable indica-
tions of light being a body capable of a chemical union
with the other ingredients of fublunary. bodies, and of
being aft^UTids let at liberty under its own form, as the
caufe wdium of vifion. 78
But tb*fe are queftions fimilar to thofe about the this
caufe of gravity, and totally unneceffary for eftablilhing®0^5 ^ a**
a complete theory of the optical phenomena, for ex-fcjenre 0f
plaining the nature of vilion, the effehls of optical in-0pttcs.
ftruments, the caufe of colours, the phenomena of the
rainbow, halos and parhelia, &c. &c. &c. Only
all this theory is unconnefted with the principles called
mechanical. ’ 79
Such is the field of obfervation to the mechanical phi- Hcpro-
lofopher of the nrefent day. We may hope to extend it,1^^?
and by degrees apply its doctrines even to the unfeentjie a’r)ove
motions which take place in chemiftry and phyfiology.extenfive
But we muft, in the firft place, perfect our knowledge (Md gfob-
and defeription of the lenfible motions and attions of^eivaUon*
bodies, t hole of fluids ftiil demand much inveftigation ;
and till thefe are thoroughly underltood, it is not time
to attempt penetrating further into the veceffes of na¬
ture.
So
In the profecution of this ftudy, it is found that every [nveiti^a-
change which can be ohferved in the ftate of a body, tion of the
with refpeci to motion by the aftion of another body, is'avXthat
accompanied by an equal and oppofitc change in the
ftate of that other body. Thus, in the phenomena ofeqUai an4
gravitation, it is obferved that the deflexions of tlie funoppofite to
and planets are mutual. The fame thing is obfervgd inrea<ftion.
the aXipns of magnets on each other and on iron 3 it is
alfo obferved in the attraXions and repulfions of eleXri-
cal bodies 3 and it alfo obtains in all the phenomena of
impulfe and of corporeal preflure. It is therefore an uni-
verfal law of motion, that action is alvoays equal and op".
pofde to reaciion : but this muft be confidered merely as
a matter of faX, a contingent latv of nature, like that
of gravitation. The contrary is perfeXly conceivable,
and involves no contradiXion. That this is fo, is evident
from the proceedings of philofophers, who in every new
cafe make it their bufinefs to difeover by experiment
whether this law was obferved or not. It was among
the laft difeoveries made by Sir Ifaac NewTon in his
examination of the celeftial motions. This being the
cafe, it fhould never be affumed as a principle of reafon-
ing till its operation has been afeertained by obfervation. gr
It has been owing to this improper procedure that much The term
falfe reafoning has been introduced into mechanical phi- uiertia has
lofophy, and particularly into the theory of impulfion or°^£10nec*
the communication of motion by impulle. In confider-wr*ano.i;ng
ing this fubjeX, a term has been introduced which has and mifccn-
occafioned much wrangling and mifconception 3 we meanception on
the term inertia. It lerves indeed to abbreviate lan-^j!^-
guage, but it has often milled the judgement. When^'" ‘
ufed with cautious attention to every circumftance, it
expreffes nothing bnt the neceffity of a caufe to the pro-
duXion of any effeX : but it is generally ufed as expref-
fing a quality inherent in matter, by which it re/ijls any
change of ftate, or by which it maintains its prefent ftate. .
Matter is faid to be inert 3 and as every thing which
changes the motion of a body is called a force, and as
this inertia of A is fuppofed to change the motion of B,
it is called vis inerticc ; and yet matter is faid to be indif¬
ferent as to motion or reft, and to be inaXive. Thefe
are -
A3 2
P H Y
Mechanical are furely very incongruous expreffions. This obfcure
Philolbphy. Jifcourfe has arifen from the poverty of all languages,
which are deficient in original terms, and therefore em¬
ploy figurative ones. Force, aftion, refiftance, are all
appropriated terms related to our own exertions; and
feme refemblance between the external eff'efts of thefe ex¬
ertions and the effefts of the connecting qualities of natu¬
ral bodies, has made us ufe them in our difquifitions on
thefe fubjefts. And as we are confcious that, in order
to prevent our being pulhed by another from our place,
we muft refill, exerting force } and that our refiftance is
the reafon why this other man has not accomplilhed his
purpofe, we fay, that the quiefcent body refills being
put in motion, and that its inertia is difcovered by
the diminution made in the motion of the impelling
body: and upon the authority of this vis inertice as a
firft principle, the phenomena of impulfion are explain¬
ed, and the law of equal aCtion and reaftion is eftablilh-
ed.
But all this procedure is in contradiction to the rules
of induCtive logic } and the obfcurity and confufion
which has arifen from this original mifconception, the
confequent incongruity of language, and the aukward
attempts that have been made to botch and accommo¬
date it to the real ftate of things, have occafioned a
difpute, and the only difpute, in natural philofophy
which has not yet been fettled, and never can be fet¬
tled, while fuch mifconceptions are allowed to re¬
main.
If the word inertia be taken as exprefling not a qua¬
lity of matter, but a law of human judgement refpeCt-
ing matter, as exprefling our neceflity of inferring the
agency of a moving force whenever we obferve a change
of motion, all difficulties will vanifti, and the equality
of aCtion and reaCtion will be inferred, as it Ihould be,
from the phenomena of collifion. There wfill be infer¬
red a vis injita corpori impellenti, not qua moventbut
qua corpori; and this inference will carry us through all
the myfteries of corporeal aCtion, as it conducted Sir
82
Its proper
meaning,
with an ex¬
ample.
A
B
1 1
D
Ifaac Newton in his grand refearches.
Let us juft confider how we reafon
in a new cafe. Let A and B be two
magnets faftened on the ends of two
long wooden laths AE, BF, which
turn horizontally on pivots C, D, like
compafs needles, with their north poles
fronting each other, 12 inches apart j
and let A be puftied towards B, fo
that it would move uniformly with the
velocity of two inches in a fecond.
The phenomena which have been ob-
ferved are as follow: A wall gradually
diminifti its velocity } and when it has
advanced about nine inches, will flop
completely. B, in the mean time
will gradually acquire motion *, and E F
when it has advanced about nine inches, will have a
velocity «f about twm inches per fecond, with which it
will continue to move uniformly. Now what is infer¬
red from thefe phenomena ? Becaufe the motion of A is
gradually retarded, wre infer that a retarding force, that
is, a force in the direction BA, has afted on it. And
fince this wmuld not have happened if B had not been
there, and always happens when B is there, wre infer
■that B is either its caufe or the occafion of its action.
4
S I c s.
The vulgar fay that B repels A ; fo fay the dynamifts. Mechanical
The abettors of invifible fluids fay, that a ftream of fluid
iffuing from B impels A in the oppofite direction. All '
naturalilts agree in faying, that an aftive force connec¬
ted with B has deftroyed the motion of A, and confider
this curious phenomenon as the indication and charadter-
iftic of a difcovery. The fame inference is made from
the motion produced in B : it is confidered by all as ef-
fedted by a force exerted or occafioned by the prefence
of A ; and the dynamifts and the vulgar fay that A re¬
pels B. And both parties conclude, from the equal
changes made on both bodies, that the changing forces
are equal 3 here acknowledging, that they obferve an
equality of adtion and readtion 3 and they add this to the
other inftances of the extent of this lawr of motion.
_ All this w hile no one thinks of the inertia or inadti-
vity of B, but, on the contrary, conclude this to be a
curious inftance of its adtivity 3 and molt people con¬
clude that both bodies carry about with them a vis in¬
jita both wffien at reft and wffien in motion.
If other phenomena give unqueftionable evidence It is doubt-
that, in ordinary collifions, there is the fame changesful whether
of motion, produced without mathematical contadt, the j^on*
fame inferences muft be drawn 3 and a fcrupulous natu-eyer been
ralift wall doybt whether contadt ftiould make any change obferved.
in our reafonings on the fubjedt, and wffiether adtual
contadt ever has been or can be obferved. He will alfo
be convinced, that while this is the general, or perhaps
univerfal, procefs of nature in producing motion by im- 84
pulfe, all explanations of the adtion of bodies e difanti, The folly
by the intervention of ethers and other invifible fluids, fuPP°-
are nothing but multiplying the difficulties 3 for in place ^g- inter‘
of one fadt, the approach of one magnet (for inftance) etherf&c.
to another, they fubftitute millions of unfeen impulfes,
each of which equally needs an explanation. And if
this fluid be fuppofed to produce its effedts by any pecu¬
liarity in its conftitution, as in the cafe of Newton’s ela-
ftic ether propofed by him to explain gravitation, the
hypothefis fubftitutes, in the moft unqualified manner,
millions of fimilar phenomena for the one to be explain¬
ed 3 for there is the fame wrant of a fecond fluid in order
to produce that mutual recefs of the particles of the ether
wffiich conftitutes its elafticity.
And this feems to be the limit to our inquiries into The quality
all the clafles of natural phenomena. We find the maf- of bodies
fes or the particles of matter endued in fadt with quali-whereb>r
ties wffiich affedt the ftate of other particles or mafles, at *^ra^°[^s
fmaller or at greater diftances from each other according is infuppor-
to certain general rules or laws. This ultimate ftep in table by us.
the conftitution of things is infcrutable by us. It is ar¬
rogance in the higheft degree for us to fay, that becaufe
we do not comprehend how there is inherent in a body
any quality by which another body may be affedted at any
diftance from it, therefore no fuch quality is pojfible. It
is no lefs fo to fay, that matter has no active property
but that of moving other matter by impulfe 3 and that
becaufe it may be fo moved, and alfo by the agency of
our own minds, therefore, wffien it is not moved by im¬
pulfe, it is moved by minds. The fame almighty fiat
wffiich brought a particle of matter into exiftence could
bring thofe qualities equally into exiftence 3 and the how
in both is equally beyond our comprehenfion.
But, on the other hand, we muft guard againft thenot j)CW
incurious refting on this confideration as a flop to fur-ever, flop
ther inquiry. There may be fpecies of matter poftcf-further iu-
ftffi quirks.
86
This fhould
P PI Y
Mechanical fed of the mechanical powers, and which notwilhftand-
Phiiokiphy. jng is not cognifable by our fenfes. All the properties
^ of matter are not known to a perfon who is both deaf
and blind } and beings poflefled of more fenfes may per¬
ceive matter where we do not j and many phenomena
may really be produced by the a£lion of intervening
matter, which we, from indolence or from hafte, afcribe
to the agency of inherent forces. The induftry of phi-
lofophers has already difcovered intermedia in fome
cafes. It is now certain that air is the conveyor of found,
and it is almoft certain that there is fuch a thing as
light. Let us therefore indulge conjeflures of this kind,
and examine the conjectures by the received laws of
motion, and rejeft them when we find the fmalleft in-
confiftency; and always keep in mind that even the
moft coincident with the phenomena is ftill but a pof-
3^ Ability.
Thefc ob- We may conclude the whole of thefe obfervations
fervations vrith the remark, that thefe queftions about the activity
a^e I01 or inaflivity of matter are not phyfical, but metaphy-
but meta- heal. Natural philofophy, it is true, commonly takes
phyficak it for granted that matter is wholly inaftive j but it is
not of any moment in phyfics whether this opinion be
true or falfe 5 wdiether matter, be afted on according to
certain laws, or whether it a<fl: of itfelf according to
the fame laws, makes no difference to the natural phi-
lofopher. It is his bufinefs to difeover the laws which
really obtain, and to apply thefe to the folution of
fubordinate phenomena : but whether thefe laws arife
from the nature of fome agent external to matter, or
whether matter itfelf is the agent, are queflions which
may be above his comprehenfion, and do not imme-
83 diately concern his proper bufinefs.
The above The account we have now given of natural philofo-
account phy points out to us in the plaineft manner the way in
tTebeft111' wkich the ftudy muff be profqputed, and the helps
method of which muff be taken from other branches of human
ftudy. knowledge.
g9 The caufes, powers, forces, or by whatever name we
This me- choofe to exprefs them, which produce the mechanical
thod fur- phenomena of the univerfe, are not obferved, and are
Gained" ami. noWn us onty in the phenomena themfelves. Our
exempli- knowledge of the mechanical powers of nature mull:
tied. therefore keep pace with our knowledge of the motions,
and indeed is nothing different from it. In order to dif¬
eover and determine the forces by which the moon is re¬
tained in her orbit round the earth, we mull know her
motions. To a terrellrial fpeftator Ihe appears to de-
feribe an ellipfe, having the earth in one focus ; but, in
the mean time, the earth is carried round the fun, and
the moon’s real path, in abfolute fpace, is a much more
complicated figure. Till we know this figure, and the
variations in the velocity with which it is deferibed, we
know nothing of the forces which actuate the moon in
0# her orbit.
The mean- When Newton fays that the forces by which Ihe is
ing of fome retained in this elliptical orbit are direfled to the earth,
!n™eaHn w^at ^oes mean ? Only this, that the deflexions from
of the celef- uniform reXilineai motion which (he would other-
tial mo- wife have performed are always in this direction. In like
tions. manner, when he fays that thefe forces are inverfely pro¬
portionate to the fquares of her diftances from the earth,
he only means that the defleXions made in equal times
in different parts of her motion are in this oronortion.
Vol. XVI. Part II.
SICS. • 433
Thefe defleXions are confidered as the charaXeriftics Mechanical
and meafures of the forces. We imagine that we have Phllo^>‘-v;
made all plain when we call this indicated caufe a ten-
(lency to the earth ; but we have no notion of this ten¬
dency to the earth different from the approach itfelf.
This word tendency, fo falhionable among the followers
of Sir Ifaac Newton, is perverted from its pure and ori¬
ginal fenfe. Tendere verfus folem, is, in the language
of Rome, and alfo of Newton, to go towards the fun •,
but we now ufe the words tend, tendency, to fignify, not
the approach, but the caufe of this approach. And when
called upon to fpeak ftill plainer, we defert the lafe paths
of plain language, and we exprefs ourfelves by meta¬
phor 5 fpeaking of nifus, conatus fefe mutua accedende,
vis centripetm, &c. When thefe expreflions have be¬
come familiar, the original fenfe of the word is forgotten,
and we take it for granted that the words never had ano¬
ther meaning ; and this metaphor, fprung from the po¬
verty of language, becomes a fruitful fource of mifeon-
ception and miftake. The only way to fecure ourfelves
againfi: fuch myftical notions as are introduced by thefe
means into philofophy, is to have recourfe to the way in
which we acquire the knowledge of thefe fancied
powers; and then wre fee that their names are only
names for phenomena, and that univerfal gravitation is
only an univerfal mutual approach among the parts of
the folar fyftem. i)X
There is one cafe in which we fondly imagine that The abfur-
we know' the caufe independent of the effcX, and that ditv of rea-
w e could have prediXed the phenomenon a priori %> wefori.inSrt
mean the cafe of impulfe : and hence it is that we are^mn!'
fo prone to reduce every thing to cafes of impulfion,
and that wre have fallen upon all thefe fubterfuges of
ethers and other fubtile fluids. Rut w’e might have
laved ourfelves all this trouble 5 for after having; by
much falfe reafoning and gratuitous affumptions, (hown
that the phenomenon in queflion might have been produ¬
ced by impulfe, vTe are no nearer our purpofe, becaufe
that property by which matter in motion puts other
matter in motion, is known to us only by and in the
effeX. 92
The fiiir and logical deduXion from all this is, that We know
we muft not expeX any knowdedge of the powers ofnotl!inS°^
nature, the immediate caufes of the motions of bodies, ^te'cTufes
but by means of a knowdedge of the motions them- Gf motions
felves; and that every miftake in the motions is ac-except by a
companied by a fimilar miftake in the caufes. It is knowledge
impoflible to demonftrate or explain the gravitation of '!tlie f0'
,r, ,. ... * ri® • r tions them-
the planets to him who is ignorant or the properties or (e|ves.
the ellipfe, or the theory of gunnery to him wdio does
not know the parabola. ^
A notion has of late gained ground, that a man may A man can-
become a natural philofopherwdthout mathematical know'- not be a
ledge ; but this is entertained by none who have any ma-
thematics themfelves •, and furely thofe who are ignorant
of mathematics ftiould not be fuftained as judges in this out being a
matter. We need only appeal to faX. It is only in mathemati-
thofe parts of natural philofophy which have been ma-cian>
thematically treated, that the inveftigations have been
carried on wdth certainty, fuccefs, and utility. Without
this guide, we muft expeX nothing but a fchool-boy’s
knowdedge, refembling that of the man who takes up
his religious creed on the authority of his prieft, and can
neither give a rettfon for what he imagines that he be-
3 I lieves,
434
Mechanical lieves, nor apply it with confidence to any valuable pur-
hhiloiophy. pQre Jn iife> \Ye xnay read and be amufed with the trif-
' jing or vague writings of a Nollet, a Fergufon, or a
Priefiley j but we hull not underhand, or profit by the
truths communicated by a Newton, a D’Alembert, or
De la Grange.
Thefe obfervations, on the other hand, fhow us the
nature of the knowledge which may be acquired, and
the rank which natural philofophy holds among the
fciences.
The mo- Motions are the real and only objects of our obfer-
tionsofho-vation, the only fubjefts of our difcufiion. In motion
t’ue.s, the are included no ideas but thofe of i’pace and time, the
of obferva-^ fubjefls of pure mathematical difquifition. As foon,
lion, are therefore, as we have difcovered the faft, the motion,
fuhjedts of all our future reafonings about this motion are purely
pure ma- mathematical, depending only on the affections of
ddl'jihhoii hgurc, number, and proportion, and muff carry along
1 rvith them that demonftration and irrefiltxble evidence
which is the boaft of that fcience. To this are we
indebted for that accuracy which is attained, and the
progrefs which has been made in fome branches of me¬
chanical philofophy *, for when the motions are di ftinelly
and minutely underllood, and then confidered only as ma¬
thematical quantities, independent of all phyfical confi-
derations, and we proceed according to the juft rules of
mathematical reafonmg, we need not fear any intricacy of
combfnation or multiplicity of fteps; we are certain that
truth will accompany us, even though we do not always
attend te it, and will emerge in our final propofition, in
the fame manner as we fee happen in a long and intri-
„ cate algebraic analyfis.
Mechanical Mechanical philofophy, therefore, which is cultivated
philofophy in this way, is not a fyftem of probable opinions, but
thus cutti- a difciplina accurata, a demonftrative fcience. To pof-
d'emo fefs it, however, in this form, requires confiderable
tM fcience. preparation. The mere elements of geometry and al¬
gebra are by no means lufficient. Newton could not
have proceeded fine “ fua mathefi faccm preferente
nd, in creating a new fcience of phyfics, he was obliged
PHYSIC S.
to fearch for and difeover a new fource of mathematical
ruatics ia
Britain,
The Amen- knowledge. It is to be lamented that the tafte for the
table decay mathematical fciences has fo prodigioufly declined in
of mathe- counjry Gf late years 5 and that Britain, which
formerly took the lead in natural philofophy, (hould
now be the country where they are leaft cultivated.
Few among us know more than a few elementary doc¬
trines of equilibrium : while, on the continent, we find
many authors who cultivate the Newtonian philofophy
with great affiduity and fuccefs, and whofe writings
are confulted as the fountains of knowledge by all our
countrymen who have occafion to employ the difeo-
veries in natural philofophy in the arts of life. It is
to the foreign writers that we have recourfe in our
feminaries, even for elementary treatxfes and while
the continent has fupplied us with molt elaborate and
ufeful treatifes on various articles, in phyfical aftrono-
nomy, practical mechanics, hydraulics, and optics, there
has not appeared in Britain half a dozen treatifes worth
con fulling for thefe laft forty years ; and this notwkh-
ftanding the unparalleled munificence of our prefent
the ampleft foverejgnj given more liberal patronage to the
mem from" cultivators of mathematical philofophy, and indeed of
fhe crown, fcience in general, than any prince in Europe. The
97
notwith-
ftanding
magnificent eftahlifirmenls of Louis XIV, originated Mechanical
from his infatiable atnbition and defire of univerfal in- hhilofophy.
flnence, directed by the fagacious Colbert. And his v f
patronage being exerted accoxding to a regular plan in
the eftablilhment of penfioned academics, and in procur¬
ing the combined eftorts of the mofl eminent of all coun¬
tries, his exertions made a confpicuous figure, and filled'
all Europe with his eulogifts. Bat all this was done
without the fmalleft felf-denial, or retrenchment of his
own pleafures, the expences being fumifhed out of the
public revenues of a great and oppreffed nation •, where¬
as the voyages of dilcovery, the expenfive obfervations
and geodetical operations in Britain, and the number-
lefs unheard-of penixons and encouragements given to
men of fcience and aftivity, were all fux-nilhcd out of
the private eftate of our excellent fovereign, who feems
to delight in repaying, by ev.ery fervice in his power,
the attachment of a loyal and happy nation. It is
therefore devoutly to be wifixed that his patriotic efforts
were properly feconded by thofe whom they are intend¬
ed to ferve, and that the tafte for the mathematical
fciences may again turn the eyes of Europe to this coun¬
try for inftrurilion and improvement. The prefent feems
a moxft favourable era, while the amazing advances in
manufactures of every kind feem to call aloud for the
afliftance of the philofopher. What pleafure would it
have given to Newton or Halley to have feconded the
ingenious efforts of a Watt, a Boulton, a Smeaton, an
Arkwright, a Dollond ? and haw mortifying is it to fee
them indebted to the fervices of a Belidor, a Boffut, a
Clairaut, a Bofcovich ?
We hope to be pardoned for this digreflion, and re-
tmm to our fubjed. ^
It appears from what has been faid, that mechani-Mechanical
cal philofophy is almoft wholly a mathematical ftudy, philofophy
and that it is to be fuccefsfully profecuted only undeASja!l^0^
tbis form : but in our endeavours to initiate the young
beginner, it will be often found to require more lleadi- cai ftudy.
nefs of thought than can generally be expe&ed for
keeping the mind engaged in fuch abftradt fpecula-
tions. The objeft prefented to the mind is not readi¬
ly apprehended with that vivacity which is neceffary
for enabling us to reafon upon it with clearnefs axxd
fteadinefs, and it would be very defirable to have (bme
means of rendering the conception more eafy, and the ^
attention more lively. This may be done by exhibit-Experi-
ing to the eye an experiment, which, though but aments are, ’
fingle faft, gives us a fenfible objeft of perception, *10W^er»
which we can contemplate and remember with much f
more fteadinefs than any mere creature of the imagi- attention of
nation. We could, by an accurate defeription, give young
fuch a conception of a room that the hearer flxould minds,
perfectly comprehend our narration of any occurrence
in it : but one moment’s glance at the room would be
infinitely better. It is ufual therefore to employ ex¬
periments to aflift the imagination of the beginner ; and
moft courfes of natural philofophy are accompanied by
a feries of fuch experiments. Such experiments, con-
nefted by a flight train of argumentative difeourfe, may
even ferve to give a notion of the general doftrines,
fufficient for an elegant amufement, and even tending
to excite curiofity and engage in a ferious profecution
of the ftudy. Such are the ufual courfes which go
by the name of experimental jbhilofophy : but this
is
PHYSICS.
Experimen- is a great mifappllcation of the term ; fuch courfes are
tal Philo- little more than illujlrations of known doctrines by ex-
fophy.
Experimen¬
tal philofo-
phy defined
and ex¬
plained.
ioi
A good
treatife on
the methoi
of inquiry
by experi-
bient very
necdTary.
t02
An objec¬
tion to ex¬
perimental
inquiry.
penments.
Experimental Philosophy is the inveftigation of
general laws, as yet unknown, by experiment; and it
has been obferved, under the article Philosophy,
that this is the moil infallible (and indeed the foie)
way of arriving at the knowledge of them. This is
the Novum Grganurn Scientiarum itrongly recommended
by Lord Bacon. It was new in his time, though not
altogether without example; for it is the procedure
of nature, and is followed whenever curioiity is excited.
There was even extant in his time a very beautiful ex¬
ample of this method, viz. the Treatife of the Load-
ftone, by Dr Gilbert of Colchefter ; a work which has
hardly been excelled by any, and which, when we con-
lider its date, about the year 1580, is really a wonderful
performance.
The molt perfedt model of this method is the Optics
of Sir Ifaac Newton. Dr Black’s Elfay on Magnefia
is another very perfedt example. Dr Franklin’s Theory
of Eledlricity is another example of great merit. That
the inveftigation is not complete, nor the conclufions
certain, is not an objedtion. The method is without
fault} and a proper diredtion is given to the mind for
the experiments which are ftill neceflary for eftablifhing
the general laws.
It were much to be wiftied that feme perfon of
talents and of extenftve knowledge wTould give a trea-
'! tife on the method of inquiry by experiment. Although
many beautiful and fuccefsful examples have been given
as particular branches of inquiry, we have but too
many inftances of very inaccurate and inconclufive in-
veftigations. Experiments made at random, aim ©ft
without a view, ferve but little to advance our know¬
ledge. They are like ftiapelefs lumps of ftone merely
detached from the rock, but ftill wanting the Ikill of
the builder to feledt them for the different purpdfes
which they may chance to lerve *, while well-contrived
experiments are blocks cut out by a Ikilful workman,
according as the quarry could furnifti them, and of
forms fuited to certain determined ufes in the future
edifice. Every little feries of experiments by Margraaf
terminates in a general law, while hardly any general
conclufion can be drawn from the numberlefs experi¬
ments of Pott. Lord Bacon has written much on this
fubjedt, and with great judgement and acutenefs of di-
ftindtion } but he has exceeded in this, and has fatigued
his readers by his numerous rules j and there is in all
his philofophical works, and particularly in this, a
quaintnefs and affedtation that greatly obfeure his mean¬
ing, fo that this molt valuable part of his writings is very
little read.
A formidable objedtion has been made to this me¬
thod of inquiry. Since a phyfical law is only the
expreflion of a general fadt, and L eftablifhed only in
confequence of our having obferved a fimilarity in a
great number of particular fadts •, and fince the great
rule of indudtive logic is to give the law no greater ex¬
tent than the indudtion on which it is founded—how
comes it that a few experiments muff be received as the
foundation of a general inference i* This has been an-
fwered in very general terms in the article Philosophy.
But it will be ofufe to confider the fubjedt a little more
particularly. Our obfervations on this fabject are taken Experimen-
from the differtation on evidence by Dr Campbell in his taj •"j)110"
Philofophy of Rhetoric. , y‘ .
An attentive conftderation of the objedts around us,
will inform us that they are generally of a complicated The objec-
nature, not only as conftfting of a complication of thofe bon
qualities of things called accidents, fuch as gravity,
mobility, colour, figure, folidity, which are common ampies
to all bodies j but alfo as ccnfifting of a mixture of aftiowingthe
variety of fubftances, very dift’erent in their nature and mature and
properties ; and each of thefe is perhaps compounded
ingredients more fimple. _ - ofTnquiryw
Moreover, the farther we advance in the knowledge
of nature, we find the more reafon to be convinced, of
her conftancy in all her operations. Like caufes have
always produced like effects, and like effedts have always
been preceded by like caufes. Inconftancy fometimes
appears in Nature’s works at jhjl Jlght; but a more re¬
fined experience (hows us that this is but an appearance,
and that there is no inconftancy j and we explain it to
our fatisfadtion in this way.
Molt of the objedts being of a complicated nature,
we find, on an accurate ferutiny, that the effedts aferi-
bed to them ought often to be folely aferibed to one
or more of thefe component parts, while the others
either do not contribute to them, or hinder their pro¬
duction •, and the variety of nature is fo great, that hard¬
ly any two individuals of the fame fpecies are in every
refpedt like any other. On all thefe accounts we ex¬
pect diffimilitudes in the phenomena accompanying per-
fedtly fimilar treatment of different fubjedls of the fame
kind) but we find, that whenever we can be affured
that the two fubftances are perfedtly alike, the pheno¬
mena arifing from fimilar treament are the fame: and
long and extenfive obfervation teaches us, that there
are certain circumftances which infure us in the perfedt
finfiilarity of conftitution of feme things. Whenever we
obferve the effect of any natural agent on one, and but
one, of thefe, we invariably expedt that the lame will be
produced on any other.
Should a botanift meet with a plant new to him, and
obferve that it has feven munopetalous flowers, he will
conclude with the utmort confidence that every plant of
this fpecies will have monopetalous flowers •, but he will
not fuppofe that it will have feven, and no more than
feven, flowers^ Now thefe two fadts feem to have no
difference to warrant fuch a difference in the conclufion 5
which may therefore feem capricious, fince there is but
one example of both.
But it is not from this example only that he draws
the conclufion. Had he never before taken notice of
any plant, he would not have reafoned at all from
thefe remarks. But Lis mind runs immediately from
this unknown fpecies to all the known fpecies of this
genus, and to all the genera of the fame order j and
having experienced in the figure of the flower an uni¬
formity in every fpecies, genus, and order, which admits
of no exception, but, in the number of flowers, a variety
as boundlefs as are the circumflances of foil, climate, age,
and culture, he learns to mark the difference, and draws
the above-mentioned conclufions. Thus we learn, that
perfeB uniformity is not to be expedted in any inftance
whatever, hecaufe in no initance is the fimplicity of con¬
ftitution fufficiently great to give us affurance of perfedt
uniformity in the circumftances of the cafe ; and the ut-
3 I 2 moft
436
Kxpei'imer.
tal Ph’io-
s fophy.
PHYSICS.
104
Mathema¬
tics do pot
{uperfede
the ufe of
experi¬
ment.
moft that our experience can teach us is a quick difcri-
mination of thofe circumftances which produce the oc-
cafional varieties.
The nearer that our inveftigations carry us to the
knowledge of elementary natures, the more are we con¬
vinced by general experience of the uniformity of the
operations of real elements \ and although it may per¬
haps be impoflible for us ever to arrive at the know¬
ledge of the fimpleft elements of any body, yet when
any thing appears fimple, or rather fo exactly uniform,
as that we have invariably obferved it to produce fimi-
lar effects on difcovering any new effedt of this fub-
ftance, we conclude, from a general experience of the
efficient, a like conftancy in the energy as to the reft.
Fire confumes wood, melts lead, and hardens clay. In
ihefe inftances it afts uniformly, but not in tbefe only.
We have always found, that whatever of any fpecies is
confumed by it in one initance, has been coniumed by
it on trial at any time. If therefore a trial be made
for the firil time of its influence on any particular fub-
ftance, he who makes it is warranted to conclude that
the effedt, whatever it may be, is a faithful reprcfenta-
tive of its dfrdls on this fubitance in all part and future
ages. This conclufion is not founded on this fmgle
initance, but upon this inftance combined with the ge¬
neral experience of the regularity of this element in its
operations.
This general conclufion, therefore, drawn from one
experiment, is by no means in oppoiition to the great
rule of indudtive logic, but, on the contrary, it is the
moft general and refined application of it. General
laws are here the real fubjedt of confderation ; and a
law itill more general, viz. that nature is cenjJant in all
its operations, is the inference which is here applied as
a principle of explanation of a phenomenon which is
itfelf a general law, viz. that nature is corjiant in this
operation.
The foundation of this general inference from one
experiment being fo firmly eftablifned, it is evident
that experiments mull be an xnfaliiole method of attain¬
ing to the knowledge of nature 5 and we need only be
folicitous that we proceed in a way agreeable to the
great rule of indudlive logic ; that is, the fubjedt mull
be cleared of every accidental and unknown circum-
itance, and put into a fituation that will reduce the
interefting circumilance to a Hate ot the greateft pof-
frble fimplicity. Thus we may be certain that the event
will be a faithful reprefentative of every fimilar cafe :
and unlefs this be done in the preparation, nothing can
j-efult from the moll numerous experiments but uncer¬
tainty and miftakes.
The account which has been given of mechanical
philofophy would feem to indicate that experiment was
not of much ule in the farther profecution of it. The
two laws of motion, with the affiftance of mathematics,
feem fully adequate to the explanation of every pheno¬
menon *, and fo they are to a certain degree. But this
degree is as yet very limited. Our mathematical know¬
ledge, great as it is in comparifon with that of former
times, is Itill infufficient for giving accurate folutions
even of very fimple (comparatively fpeaking) queftions.
We can tell, with the utmoft precifioh, what will be the
motions of two particles of matter, or two bodies, which
adt on each other with forces proportioned to the fquares
of the diitances inverfely \ but if we add a. third par¬
ticle, or a third body, acting by the fame law, the unit- Expcnmen-
ed fcience of all Europe can only give an approximation taj:0^y°"
to the folation. 1 y——>
What is to be done then in the cafes which come 105
continually before us, where millions of particles are Experiment
acting at once on each other in every variety of fitu-15 °ften tlie
ation and d:fiance ? How fhall we determine, for in- °ou^cei
fiance, the motion of water through a. pipe or fluice
when urged by a pi Ron or by its own weight i what will
be its velocity and direction ? It is impoffible, in the
prefent flute of mathematical knowledge, to tell with
any precifion or certainty. And here we mull have
recourfe to experiment. But if this be the cafe, mult
the experiment be made in every poffible variety of fitu¬
ation, depth, figure, preffure ? or is it poffible to finer
out any general rules, founded on the general laws of
motion, and rationally deduced from them ? Or, if this
cannot be accompliffied, will experiment itfelf furnifh
any general coincidences which Ihow fuch mutual de¬
pendences, that we may confider them as indications of
general principles, though fubordinate, complicated, and
perhaps infcrutable ? This can be difeovered by experi¬
ment alone. 106
The attention of philofophers has been diredled to Accurate
each of thefe three chances, and confider able progrefs
has been made m them all. Numerous experiments not a]wayS
have been made, almoft fufficient to direct the praftice be made,
in many important cafes, without the help of any rule
or principle whatever. But there are many cafes, and
thefe of by far the greateft importance, fuch as the
motion of a fliip impelled by the winds, refilled by the
water, and tofled by the waves, where diilindt experi¬
ments cannot be made. 107
Newton, Bernouilii, d’Alembert, and others, have Exair ule of
laboured hard to deduce from the laws of motion rules
for determining what may be called the average mo-
tion of water in thefe circumftances, without attempt¬
ing to define the path or motion of any individual par¬
ticle ; and they have actually deduced many rules which
have a great degree of probability, it may here be
afked, why do you fay probability ? the rules, as far as
they go, fhould be certain. So they are : they are ft rift
deductions from their premiffes. But the premiffes are
only fuppojitwns, of various degrees of probability, ai-
fumed in order to fimplify the circumftances of the cafe,
and to give room for mathematical reafoning ; therefore
thefe deductions, thefe rules, mull be examined by ex¬
periment. Some of the fuppofitions are fuch as can
hardly be refufed, and the rules deduced from them are
found to tally precifely with the phenomena. Such is
this, “ that the velocities of iffuing water in fimilar cir¬
cumftances are in the fub-duplicate ratio of the pref-
fures.” And this rule gives a moft important and _ex-
tenftve information to the engineer. Gtner fuppofitions
are more gratuitous, and the rules deduced from them
are lefs coincident with the phenomena. 1 he patient
and fagacious Newton has repeatedly failed in his attempts
to determine what is the abfolute velocity of water iffuing
from a hole in the bottom of a veffel when urged by its
weight alone, and the attempts of the others have hardly
fucceeded better. Experiment is therefore abfolutely
neceffary on this head.
Thofe who have aimed at the difeovery of rules pure¬
ly experimental on this fnbjeCt, have alfo been pretty
fuccefsful; and- the Chevalier Buat has, from a compari¬
fon
lop
in naviga¬
tion,
PHY
Experimen- fon of an Immenfe variety of experiments made by hirri-
tal Phiio- felf and various authors, deduced an empirical rule,
, fop^y~ , which will not be found to deviate from truth above one
part in ten in any cafe which has yet come to our know¬
ledge.
This inftance may ferve to Ihow the ufe of experi¬
ments in mechanical philofophy. It is proper in all
cafes by way of illuflration ; and it is abfolutely necef-
fary in moft, either as the foundation of a charadteriftic
of a particular clafs of phenomena, or as argument in
fupport of a particular doctrine. Hydroftatics, hydrau¬
lics, pneumatics, magnetifm, eledtricity, and optics, can
hardly be ftudied in any other way •, and they are at
prefent in an imperfedt ftate, and receiving continual
improvement by the labours of experimental philofophers
iog in all quarters of the world.
The advan- Having m th* preceding paragraphs given a pretty
tages de- full enumeration of the different fubjedts which are to
nved from be confidered in the ftudy of natural philofophy, it
tile. -I 7 will not be neceffary to fpend much time in a detail of
the advantages which may reafonably be expedled from
a fuccefsful profecution of this ftudy. It (lands in no
need of panegyric : its intimate connedlion with the
arts gives it a fufficient recommendation to the atten¬
tion of every perfon. It is the foundation of many
arts, and it gives liberal afliftance to all. Indebted to
them for its origin and birth, it has ever retained its
filial attachment, and repaid all their favours with the
moft partial afifedlion.
To this fcience the navigator muft have recourfe
for that aftronomical knowledge which enables him
to find his place in the tracklefs ocean ; and although
very fmall (craps of this knowledge are fqfficient for the
mere pilot, it is neceffary thdt the ftudy be profecuted
to tire utmoft by Tome perfons, that the unlearned pilot
may get that fcanty pittance which muft diredt his
routine. The few pages of tables of the fun’s decli¬
nation, which he ufes every day to find his latitude,
required the fucceflive and united labours of all the
aftronomers of Europe to make them tolerably exadt :
and in order to afcertain his longitude with precifion,
it required all the genius of a Newton to detedl the
lunar irregularities, and bring them within the power
of the calculator ; and, till this was done, the refpedlive-
pofition of the different parts of the earth could not be
afcertained. Vain would have been the attempt to do
this by'geodaetical furveys independent of aftronomical
obfervation. It is only from the moft refined mecha¬
nics that we can hope for fure principles to diredt us
in the conftrudlion and management of a (hip, the
boaft of human art, and the great means of union and
communication between the different quarters of the
no globc-
in archite'c- A knowledge of mechanics not much inferior to
ture, this is neceffary for enabling the architect to execute
Tome of his greateft works, fuch as the eredtion of domes
and arches, which depend on the niceft adjuftment of
equilibrium. Without this he cannot unite economy
with ftrength 5 and his works muft either be clumfy maf-
lir fes or flimfy (hells.
in gunnery The effedls of artillery cannot be underftood or fe-
and ether cured without the fame knowdedge.
engines, The whole employment of the engineer, civil or mi¬
litary, is a continual application of almoft every branch
of. mechanical knowledge .5 and while the promifes of
SICS. 437
a Smeaton, a Watt, a Belidor, maybe confided in asE5;per>men*
if already performed, the numberlefs failures and difap- la^phlio-
pointments in the moft important and coftly projedis , y ■
(how us daily the ignorance of the pretending crowd
of engineers.
The microfcope, the (team-engine, the thunder-rod,
are prefents which the world has received from the na¬
tural philofopher } and although the compafs and tele-
fcope were the produdlions of chance, they would have
been of little fervice had they not been ftudied and im¬
proved by Gilbert, Halley, and Dollond.
But it is not in the arts alone that the influence of na¬
tural philofophy is perceived : it lends its aid to every
Tcience, and in every ftudy.
It is often necelfary to have recourfe to the phiio- ;n |aw
fop’ner in difputes concerning property; and many Ex¬
amples might be given where great injuftice has been
the confequence of the ignorance of the judges. Know¬
ledge of nature might have prevented many difgrace-
ful condemnations for forcery.
The hiftorian who is ignorant of natural philofbphy in biftoryy
eafily admits the miraculous into his narrations, accom¬
panies thefe with his refledlions, draws confequences from
them, and fills his pages with prodigies, fables, and ab-
furdity. ° . „4
It is almoft needlefs to fpeak of tbe advantages ;n medi-
wdiich will accrue to the phyfician from this ftudy. So cine,
clofe is the connedlion between it and medicine, that
our language has given but one name to the naturaliil
and to the medical philofopher. Indeed, the whole
of his ftudy is a clofe obfervation of tire laws of mate¬
rial nature, in order to draw from them precepts to
diredt his pradtice in the noble art of healing. Du¬
ring the immaturity of general knowledge, while na¬
tural philofophy was the only ftudy which had acquired
any juft pretenfion to certitude either in its principles
or method of inveftigation, the phyficians endeavoured
to bring the objedls of their ftudy w ithin its province,
hoping by this means to get a more diftindl view of it j
and they endeavoured to explain the abftrufe pheno¬
mena of the animal fundlions by reducing them all to
motions, vibrations, collifions, impulfes, hydroftatic
and hydraulic preffures and adlions, with which the
mechanical philofophers wrere fo ardently occupied at
that time. But unfortunately their acquaintance with
nature/was then very limited, and they were but little
habituated to the rules of juft reafoning ; and their
attempts to explain the economy of animal life by the
law's of mechanics did them but little fervice either for
the knowledge of difeafes or of the methods of cure.
The mechanical theories of medicine, which had confi-
derable reputation about the end of the 17th century,
were many of them very ingenious, and had an impofing
appearance of fymmetry and connedlion ; but are now
forgotten, having all been formed on the narrow fup-
pofition that matter was fubjedl only to mechanical
laws.
But the difcovery of error diminilhes the chance of
again going w'rong, efpecially when the caufe of error
has been difcovered, and the means pointed out of de-
tedling the miftakes ; and the vital principle muft com¬
bine its influence with, or operate on, the properties of
rude matter. It appears therefore evident that a kno’.v-
ledge of the mechanical law's of the material world is
not only a convenient, but .a neceffary, accompli(hment
to
. IT5
in relieion
433
E.TnL™eIvt0 t1ie ^yfician. _ We are fully jm^fied in this opinion,
by obferving medical authors of the prefent day intro¬
ducing into medicine theories borrowed from mechani¬
cal philofophy, which they do not underhand, and which
they continually mifapply. Appearance of reafoning
frequently conceals the errors in principle, and feldom
fails to millead.
But there is no clafs of men to whom this fcience
is of more tervice than to thofe who hold the honour¬
able office of the teachers of religion. Their know¬
ledge in their own fcience, and their public utility,
are prodigiouily hurt by ignorance of the general frame
and conftitution of nature } and it is much to be la¬
mented that this fcience is fo generally negledled by
them, or confidered only as an elegant accompliffirnent:
nay, it is too frequently Ihunned as a dangerous attain¬
ment, as likely to unhinge their own-faith, and taint
the minds of their hearers. .We hope, however, that
few are either fo feebly rooted in the belief of the great
do61rir.es of religion as to fear this, or of minds fo bafe
and corrupted as to adopt and inculcate a belief which
they have any fufpicion of being ill-founded. But
many have a fort of horror at ail attempts to account
for the events of nature by the intervention of general
caufes, and think this procedure derogatory to the
Divine nature, and inconfiftent with the do61rine of
his particular providence believing, that “ a fparrow
does not fall to the ground without the knowledge of
our heavenly Father.” d heir limited conceptions can¬
not perceive, that, in forming the general law, the
Great Artift did at one glance lee it in its rerhotell and
moll minute confequence, and adjuffc the vaft affemblage
fo as completely to anlWer every purpefe of His pro¬
vidence. There never wTas a more eager enquirer into
the laws of nature, or more ardent admirer of its glo¬
rious Author, than the Hon. Robert Boyle. This gen¬
tleman fays, that he will always think more highly of
the {kill and power of that artill who (hcruld conftruft
a machine, which, being once fet a going, would of it-
lelf continue its motion for ages, and from its inherent
principles continue to anfwer all the purpofes for which
it was firil contrived, than of him whofe machine re¬
quired the continual aid of the hand which firlf con-
itrudlcd it. It is owing to great inattention that this
averlion to the operation of fecondary caufes has any
influence on our mind. What do we mean by the in-
trodu6fion of fecondary caufes r How do we infer the
agency of any caufe whatever ? Would we ever have
fuppofed any caufe of the operations of nature, had they
gone on without any order or regularity ? Or would
luch a chaos of events, any more than a chaos of exift-
ences, have given us any notion of a forming and direct¬
ing hand ? No ffirely. We fee the hand of God in the
regular and unvaried courfe of nature, only becaufe it is
regular and unvaried. The philofopher expreffes this
by faying, that the phenomena proceed by unalter¬
able laws. Greatly miflaken therefore are they who
think that we luperfede the exillence of mind and of
providence when we trace things to their caufes. A
phyfical law being an unvaried fact, is an indication,
and the ftrongeft poffible indication, of an unerring
4 jrer^u. mind, who is incapable of change, and mult do to day
/bn’s Lee what He always did : for to change is to deviate from
tures on what is belt *. The operations of unerring mind wall
£thics. therefore be regular and invariable. Phyfical laws,
2> •
PHYSICS.
fephy.
116
therefore, or fecondary caufes, are the bell proofs of un- Experiment
erring wifdom. Such regularity of conduct is univer- ral Phil°-
fally confidered as an indication of wifdom among men.,
The wife man is known by the conjfancy of his ccn-
du6t, while no man can depend on the future conduct of
a fool.
And what aftoniffiing evidences of wifdom do we
not obferve in the general laws of the material world ?
They will ever be confidered by the intelligent philo¬
fopher as the moll glorious dilplay of inconceivable
wifdom, which has been able, by means fo few and fo
fimple, to produce effe6ts which by their grandeur ailo-
nifia our feeble underllandings, and by their inexhauftible
variety elude all poffibility of enumeration.
W hile the teachers of religion remain ignorant of
the beautiful law^s of nature, the great chara61eriftics
of the wifdom and goodnefs of the Almighty Creator,
their hearers are deprived of much fublime pleafurej
God is robbed of that praife which he would have re¬
ceived from an enlightened people \ and the only wor-
finp he receives is tainted with mean notions of his at¬
tributes, and groundlefs fears of his powder.
But befides thefe advantages which accrue io diffe¬
rent claffes of men from this Rudy, there are forne ef-
fefts which are general, and are too important to be
paffed over unnoticed.
f hat fpirit of difpaffionate experimental enquiry 0_
which has fo greatly promoted this Rudy, will carry ther fei-
with it, into every fubje6f of enquiry, that precifionenceSi
and that conflant appeal to faft and experience which
chara6Ierize it. And we may venture to affert, that
the iuperior good order and method which diRinguilh
feme of the later produftions in other fciences, have
been in a great meafure owing to this mathematical
fpirit, the luccefs of wduch in natural philofophy has
gained it credit, and thus given it an unperceived
influence even over thofe who have not made it their
Rudy.
1 he truths alfo which the naturaliR difeovers are More ge-
fuch as do not in general affeft the paflions of men,neralad-
and have therefore a good chance of meeting with avantaSeso^
candid reception. Thofe whofe interefl it is to keep men philofoph
in political or religious ignorance, cannot eafily fufpeft
bad confequences from improvements in this fcience j
and if they did, have hardly any pretext for checking
its progrefs. And difeoveries accuflom the mind to no¬
velty ; and it will no longer be Rartled by any confe¬
quences, however contrary to common opinion. Thus
the way is paved for a rational and difereet fcepticifm,
and a free enquiry on other fubjehfs. Experiment,
not authority, will be confidered as the tefl of truth j
and under the guidance of fair experience we need
fear no ill as long as the latvs of nature remain as they
are.
Laftly, fince it is the bufinefs of philofophy to de-
feribe the phenomena of nature, to difeover their cau¬
fes, to trace the conneflion and fubordination of thefe
caufes, and thus obtain a view' of the whole conRitu-
tion of nature ; it is plain that it affords the furefl path
for arriving at the knowledge of the great caufe of all,
of God himfelf, and for forming proper conceptions
of him and of our relations to him : notions infinitely
more juR than can ever be entertained by the carelefs
fpe61ator of his works. Things ■which to this man ap¬
pear folitary and detached, having no other connec¬
tion,
PHYSICS. 439
penmen- tion with the reft of the umverfe but the fhadowy and God, and with the hopes of one day enjoying all the fa- Experimew
tal Philo, fleeting relation of co-exiftence, will, to the diligent tisfaftion that can ariie from confcious worth and con-
fol)hy philofopher, declare themfelves to be parts of a great fummate knowledge; and^ this is the worftiip which God
1 an(j liarinonious whole, connefted by the general laws will approve. “ -This univerfe (fays Boyle) is the mag-
of nature, and tending to one grand and beneficent nificent temple of its great Author j and man is ordain-
purpofe. Such a contemplation is in the higheft degree ed, by his powers and qualifications, the high prieft of
pleafant and cheering, and cannot fail of imprefhng us nature, to celebrate di\me fervice in this temple Oj. the
with the wifti to co-operate in this glorious plan, by a£l- univerfe.'”
ing worthy of the place we hold among the works of
PHYSIOGNOMONIC3, among phyficians, denote
fuch figns as, being taken from the countenance, ferve
to indicate the ftate, difpofition, &.c. both of the body
and mind : and hence the art of reducing thefe figns to-
practice is termed physiognomy.
PHYSIOGNOM Y
i T S a word formed from the Greek <pv7i; nature, and
Various de- x ylV0)T^u / knoiu. It is the name of a faience which
^h^f°nS occupied much of the attention of ancient philolo-
iny1 ancient phers, and which,.fmee the revival of learning, has in
and mo- a great degree been dilregarded. I ill of late it lias
dern. feldom in modern times been mentioned, except in
conjunftion with the exploded arts of magic, alchemy,
and judicial aftrology. Within the laft two centuries,
no doubt, the bounds of human knowledge have been
greatly extended by means of the patient purfuit of
ta<ft and experiment, inftead of the hafty adoption of
conjecture and hypothefts. We have certainly difco-
vered many of the ancient fyftems to be mereiy crea¬
tures of imagination. Perhaps, however, in fome in-
fiances, we have decided too rapidly, and rejected real
knowledge, which we would have found it tedious and
troublefome to acquire. Such has been the fate of the
fcience of phyftognomy j which certainly merits to be
confidered in a light very different from alchemy and
thofe other fanciful ftudies with which it bad acciden¬
tally been coupled. Ihe work lately pubiifhed by
M. Lavater on the fubject has indeed excited attention,
and may perhaps tend to replace phyfiognomy in that
rank in the circle of the fciences to which it feems to be
in titled.
It does not appear that the ancients extended the
compafs of phyfiognomy beyond man, or at leaft ani¬
mated nature : But the 'ftudy of that art was revived
in the middle ages, when, mifted probably by the com-
prehenfivenefs of the etymological meaning of the
word, or incited by the prevalent tafte for the mar¬
vellous, tbofe who treated of the fubjeft ftretched the
range of their fpeculation far beyond the ancient li¬
mits. The extenfion of the fignification of the term
was adopted univerfally by tbofe naturalifts who ad¬
mitted the theory of fignatures (fee Signature) ; and
phyfiognomy came thus to mean, the knowledge of the
ftf/e/wu/properties of tf/ry corporeal exiftence from the
external appearances. Joannes Baptifta Porta, for in-
fcance, who was a phyfiognomift and philofopher of con-
fiderable eminence, wrote a treatife on the phyfignemy
of plants (philognomonica'), in which he employs phy¬
fiognomy as the generic term. There is a treatife
tikewife De Physiognomia Avium, written we believe by
the fame perfon. In the Magia Physiognomica of Gai-
par Schottus, physiognomia humana is made a fuhdivifion
of the fcience.
Boyle too adopts the extenfive fignification men¬
tioned, which indeed feems to have been at one time
the ufual acceptation of the word (a). At prefent
phyfiognomy feems to mean no more than “ a know¬
ledge of the moral charadler and extent of intelleiftual
powers of human beings, from their external appear¬
ance and manners.” In the Berlin Tranfaflions for
the years 1769 and 1770 there appears a long contro-
verfial difeuflion on the fubjetft of the definition of phy¬
fiognomy between M. Pernetty and M. Le Cat, two
modern authors of fome note. Pernetty contends that
all knowledge whatever is phyfiognomy j Le Cat con¬
fines the fubjeft to the human face. Neither feems to
have hit the medium of truth. Soon after the cele¬
brated book of Lavater appeared. He indeed defines
phyfiognomy to be, “ the art of difeovering the interior
of man by means of his exterior •, but in difterent paf-
fages of his work he evidently favours the extended
fignification of Pernetty. This work gave occafion
to M. Formey’s attack upon the fcience itfelf in the
fame Berlin Tranfadftions for 1775. Formey ftrenuoufly
controverts the extent afligned by Lavater to his favour¬
ite fcience. , 2
Before the era of Pythagoras the Greeks had little or Pythagoras
no fcience, and of courfe could not be fcientifical phyfi- probably
ognomifts. Phyfiognomy, however, was much cultiva-
ted in Egypt and India } and from thefe countries the t0 Greece.
fage
^a) They’ll find i’ the phyfiognomies
0’ th"1 planets all men’s deftinies.
Hudibras.
44°
PHYSIOGNOMY.
fage of Samos probably introduced the rudiments of this
fcience,- as he did thofe of many others, generally deem¬
ed more important, into Greece.
It was a I11 t;^e t™6 Socrates it appears even to have been
profeffion adopted as a profeffion. Of this the well-known anec-
m the time dote of the decifion of Zopyrus, on the real charafter
■ot Socrates. 0p Socrates himfelf, judging from his countenace, is fuf-
ficient evidence. Plato mentions the fubjedf *, and by
Ariitotle it is formally treated of in a boolk allotted to
the purpofe.
It may be worth while to give a brief outline of Ari-
^ ftotle’s fentiments on the fubjedl.
General Phyfiognomy, he in fubftance obferves, had been
outline of treated of in three ways : Some philofophers clafled
Arittotle’s ariJinals into genera, and afcribed to each genus a cer-
S01 *-a^n mental difpofition correfponding to their corpo-
jedt. real appearance. Others made a farther diftindfion of
dividing the genera into fpecies. Among men, for
in dance, they diftinguilhed the Thracians, the Scy¬
thians, the Egyptians, and whatever nations were ftri-
kingly different in manners and habits, to whom ac¬
cordingly they affxgned the diftinftive phyfiognomical
character!ffics, A third fet of phyfiognomifts judged
of the actions and manners of the individual, and pre¬
fumed that certain manners proceeded from certain
difpolitions. But the method of treating the fubjeft
adopted by Ariftotle himfelf whs this: A peculiar
form of body is invariably accompanied by a peculiar
difpofition of mind 5 a human intellect is never found in
the corporeal form of a bead. The mind and body re¬
ciprocally affeft each other : thus in intoxication and
mania the mind exhibits the affediions of the body 5 and
in fear, joy, &c. the body difplays the affedlions of the
mind.
From fuch fadfs he argues, that when in man a par¬
ticular bodily charadler appears, which by prior experi¬
ence and observation has been found uniformly accom¬
panied by a certain mental difpofilion, with which there¬
fore it mud have been neceffarily connedled ; we are
intitled in all fuch cafes to infer the difpofition from
the appearance. Our obfervations, he conceives, may
be drawn from other animals as well as from men : for
as a lion poffeffes one bodily form and mental charadler,
a hare another, the corporeal charadleridics of the lion,
fuch as drong hair, deep voice, large extremities, dif-
cernible in a human creature, denote the drength and
courage of that noble animal •, while the dender extre¬
mities, fo ft down, and other features of the hare, vifible
in a man, betray the mental charadler of that pufillani-
mous creature.
Upon this principle Aridotle treats of the corporeal
features of man, and the correfpondent difpofitions, fo far
as obferved : he illudrates them by the analogy jud men¬
tioned, and in feme indances attempts to account for
them by phyfiological reafoning.
At the early period in which Aridotle wrote, his theo¬
ry, plauffole certainly, and even probable, difplays his
ufual penetration and a confiderable degree of know¬
ledge. He didindlly notices individual phyfiognomy,
national phyfiognomy, and comparative phyfiognomy.
The date of knowledge in his time did not admit of a
complete elucidation of his general principles ; on that
account his enumeration of particular obfervations and
precepts is by no means fo well founded or fo accurate as
his method of dudy. Even his dyle, concife and energe-
2
tic, was inimical to the fubje£l j which, to be made clear¬
ly comprehendble, mud require frequent paraphrafes.
Aridotle’s performance, however, fuch as it is, has been
taken as the groundwork and model of every phyfiogno¬
mical treatife that has fince appeared.
The imitators of this great man in the 16th and 17th
centuries have even copied his language and manner,
which are fententious, indiferinrinate, and obfeure. His
comparative phyfiognomy of men with beads has been
frequently though not univerfally adopted. Befides his
treatiie exprefsly on the fubjeft, many incidental obfer¬
vations on phydognomy will be found interfperfed
through his other works, particularly in his hidory of
animals. ^
Next after Aridotle, his difciple and fucceffor The-Theophraf-
ophradus would deferve to be particularly mentioned tu',’s ethic
as a writer on the fubjedt in quedion. His ethic cha-^’araclers
radlers, a Angular and entertaining performance, com- important
pofed at the age of 99, form a didindl treatife on a branch of
mod important branch of phyfiogr.omy, the physiognomy phyfiogno-
of manners: but the trandations and imitations of La^
Bruyere are fo excellent, that by referring to them we
do greater judice than would otherwife be in our
power, both to Theophradus and to our readers. We
cannot, however, omit obferving, that the accuracy of
obfervation and livelinefs of defeription difplayed in the
work of Theophradus will preferve it high in cladi-
cal rank, while the fcience of man and the prominent
charafleridics of human fcciety continue to be objedls
of attention. ^
Polemon of Athens, Adamantius the fopbid, and fe other
veral others, wrote on the fubjedl about the fame pe- G eek au-
riod. Lately there was publifhed a colledlion of all thethorson
Greek authors on phydognomy: the book is intitled,
Physiognomure veteris feriptores Greed, Gr. et Lat. a ^
Framzio Altenb. 1780, 8vo. From the number of thefe f.;ence
authors, it appears that the fcience was much cultivated was tt,„n
in Greece*, but the profeffors feem foon to have connedl-coupled
ed with it fomething of the marvellous. This we have with fome-
caule to fufpedl from the dory told by Apion of ApelW1*11^ of the
les : Imaginem adeo Jimilitudinis indiferetee pinxit, ut r'ai1' 1 *
(incrcdibilc dicin') Apion Grammaticus Scriptum reliqnerit
quemdam ex facie hominum addivinantem (quos melapof-
copos vacant^ ex Us dixijfe aui futurce mortis annos, aut
preeteritee *. The noviciates of the Pythagorean fchool « pn;ly
were fubjecled to the phyfiognomic obfervation of their j\7at. Hijt.
teachers, and it is probable the fird phyfiognomids by lib. 35.
profedion among the Greeks were of this feed. They, § 35* Par*
loo, to whom, from the nature of their dodlrines and
difeipline, mydery was familiar, were the fird, it is
likely, who expofed the fcience of phyfiognomy in
Greece to difgrace, by blending with it the art of divi¬
nation. g
From the period of which we have been treating toTheobfer-
the clofe of the Roman republic, nothing worthy of vat ions of
remark occurs in the literary hidory of phvfiognomy. ^°man a.n^
About the lad mentioned era, however, and from thence ters
to the decline of the empire under the later emperors,
the fcience appears to have been cultivated as an im¬
portant branch of erudition, and affumed as a profeffion
by perfons who had acquired a fuperior knowledge
in it.
In the works of Hippocrates and Galen, many phy¬
fiognomical obfervations occur. Cicero appears to have
been peculiarly attached to the fcience. In his ora¬
tion
44i
PHYSIOGNOMY.
t$on again ft Pxfo, and in that in favour of Rofcius, the
reader will at the fame time perceive in what manner
the orator employs phyfiognomy to his purpofes, and
find a curious inftance of the ancient manner of oratori¬
cal abufe.
Many phyfiognomical remarks are to be found like-
wife in the writings of Salluft, Suetonius, Seneca, Pliny,
Aulus Gellius, Petronius, Plutarch, and others.
That in the Roman empire the fcience was pra&ifed
as a profeftion, ample evidence appears in the writings
of feveral of the authors juft mentioned. Suetonius,
for inftance, in his Life of Titus, mentions that Nar-
ciffus employed a physiognomifl to examine the features
of Britannicus, who predicted that Britannicus would
not fucceed, but that the empire would devolve on
Titus.
This fcience The fcience of phyfiognomy (hared the fame fate with
fell with all others, when the Roman empire was overthrown by
the Roman the northern barbarians. About the beginning of the
em^)ire‘ 16th century it began again to be noticed.—From that
time till the clofe of the 17th,. it wTas one of the moft
fafhionable ftudies. Within that fpace have appear¬
ed almoft all the approved modern authors on the fub-
jeft (b).
It has been unfortunate for phyfiognomy, that by ma¬
ny of thefe writers it was held to be connected with doc¬
trines of which the philofophy of the prefent day would
be aftiamed. With thefe doftrines it had almoft funk
io into oblivion.
Particular In every period of the hiftory of literature there may
ftudies have eafily be marked a prevalence of particular ftudies. In
peculiarly the early period, for inftance, of Grecian literature, my-
oarticul^ ^ thological morality claimed the chief attention of the phi-
times!U af lofophers. In the more advanced (late of learning in
Greece and in Rome, poetry, hijlory, and oratory, held
the pre-eminence. Under the latter emperors, and for
fome time afterwards, the hiftory of theological contro-
verjies occupied the greateft part of works of the learn¬
ed. Next fucceeded metaphysics, and metaphysical theo¬
logy. Thefe gave place to alchemy, magic, judicial
qflrology, the do&rine of fignatures and fympathies, the
mystic, theofophic, and Rojicrucian theology, with phy¬
fiognomy. Such were the purfaits contemporary with
the fcience which is the object of our prefent inquiry.
It is no matter of furprife, that, fo afibciated, it (hould
have fallen into contempt. It is not unufual for man¬
kind haftily to reje& valuable opinions, when acciden¬
tally or artificially connedfted with others which are ab-
furd and untenable. Of the truth of this remark, the
hiftory of theology, and the prefent tone of theological
opinions in Europe, furnifh a pregnant example.
To phyfiognomy, and the exploded fciences laft men¬
tioned, fucceeded clajjic philology ; which gave place to
modern poetry and natural philofophy ; to which recent¬
ly have been added the ftudies of rational theology, che-
Vol. XVI. Part II.
mijlry, the philofophy of hi/lory, the hijlory of man, and
the fcience of politics. \ 1
About the commencement of the 18th century, and The oufer-
thence forward, the occult fciences, as they are termed, vations of
had declined very confiderably in the eftimation of the of ^h^pre-
leamed ; and thofe who treated of phyfiognomy forbore fent centu-
to difgrace it by a connexion with thofe branches of ry on this
ideal learning with which formerly it had been invari- fubjedt.
ably conjoined. In Britain, Dr Gwither noticed it with
approbation.—His remarks are publiftied in the Philofo-
phical Tranfa&ions, vol. xviii. 5 and Dr Parfons chofe
it for the fubjeft of the Croonean lectures, publiftied at
firft in the fecond fupplement to the 44th volume of the
Philofophical Tranfaftions, and afterwards (1747) in
a feparate treatife, entitled Human Physiognomy ex¬
plained.
The obfervations, however, of thefe writers, as well
as of Lancifius, Haller, and Buffon, relate rather to the
tranfient expreflion of the paftions than to the permanent
features of the face and body. The well-known charac¬
ters of Le Brun likewife are illuftrative of the tranfient
phyfiognomy, or (as it is termed) pathognomy.—See
Passions in Painting. lz
During the prefent century, although phyfiognomy We find
has been now and then attended to, nothing of import- nothing
ance appeared on the fubjebt till the difcuflion already Yery ,rn"
mentioned between Pernetty and Le Cat, in the Berlin
Tran factions. The fentiments of thefe authors, in fo farControver-
as relates to the definition of phyfiognomy, have been fy between
above noticed. Their effays are, befides, employed in t'ernetty
difcufling the following queftions: 1 ft, Whether it would an“ ^ Cat*
or would not be advantageous to fociety, were the cha-
rafter, difpofition, and abilities, of each individual fo
marked in his appearance as to be difcovered with cer¬
tainty ?
2dly, Whether, on the fuppofition that by the high-
eft poflible proficiency in phyfiognomy, we could attain
a knowledge in part only of the internal character, it
would be advantageous to fociety to cultivate the ftu-
dy, mankind being in general imperfeft phyfiogno-
mifts ?
No reafoning a priori can poflibly determine thefe
queftions. Time and experience alone muft afcertain
the degree of influence which any particular acquifition
of knowledge would have on the manners and charac¬
ters of mankind ; but it is difficult to conceive how the
refult of any portion of knowledge, formerly unknown,
and which mankind would be permitted to difcover, could
be any thing but beneficial. ^
Soon after this controverfy in the Berlin Tranfaftions, Lavater’s
appeared the great work of M. Lavater, dean of Zurich, celebrated
which has excited no inconfiderable portion of attentionWorICi
in the literary world. The work itfelf is magnificent:
That circumftance, as well as the nature of the fubjeft,
which was fuppofed to be fanciful, have contributed to
3 K extend
(b) They are, Bartholem. Codes, Baptifta Porta, Honoratus Nuquetius, Jacobus de Indagine, Alftedius, Mi¬
chael Schottus, Gafpar Schottus, Cardan, Taifnierus, Fludd, Behmen, Barclay, Claromontius, Conringius,
the commentaries of Auguftin Niphus, and Camillus Balbus on the Phyfiognomica of Ariftotle, Spontanus
Andreas Henricus, Joannes Digander, Rud. Goclenius, Alex. Achillinus, Joh. Praetorius, Jo. Belot, Guliel. Gra-
talorus, &c. They are noticed in the Polyhiftor of Morhoff, vol. i. lib. i. cap. 15. § 4. and vol. ii, lib. iii.
cap. 1. J 4.
0
442
His opi¬
nions the
refult of
obferva-
tion.
His ima¬
gination
has, how¬
ever, often
qutftript
his judge¬
ment.
* Vol. i.
R- 33—38.
vol. ii.
p. 89.
French
franfla-
tion.
f VoJ. i.
p. ie6.
16
Other
weakneffes
of this
great phy-
hognomift
PHYSIO
extend its fame ; and certainly, if we may judge, the
book, though many faults may be detefted in it, is the
moft important of any that has appeared on the fub-
jt£t fince the days4’ of Ariftotle. Lavater profefles not
to give a complete fynthelical treatife on phyliognomy,
but, aware that the fcience is yet in its infancy, he ex¬
hibits fragipents only, illuftrative of its different parts.
His performance is no doubt defultory and unconnect¬
ed. It contains, however, many particulars much fupe-
rior to any thing that had ever before appeared on the
fubjeft.
With the fcholaftic and fyftematic method adopted by
the phyfiognomifts of the laft and preceding centuries,
Lavater has rejected their manner of writing, which was
dry, concife, indeterminate, and general: His remarks,
on the contrary, are, for the molt part, precife and par¬
ticular, frequently founded on diftinctions extremely
acute. He has omitted entirely (as was to be expelled
from a writer of the prefent day) the aftrological reve¬
ries, and fuch like, which deform the writings of former
phyfiognomifts ; and he has with much propriety dedu¬
ced his phyfiognomical obfervations but feldom from
anatomical or phyfiological reafoning. Such reafoning
may perhaps at fome future period become important 5
but at prefent our knowledge of fafts, although exten-
five, is not fo univerfal, as to become the liable founda¬
tion of particular dedudlions. Lavater has illuftrated
his remarks by engravings •, a method firft adopted by
Baptifta Porta.—Lavatef’s engravings are very nume¬
rous, often expreflive, and tolerably executed.
The opinions of this celebrated phyfiognomift are evi¬
dently the refult of actual obfervation. He appears in¬
deed to have made the fcience his peculiar ftudy, and
the grand purfuit of his life. His performance exhibits
an extended comprehenfion of the fubjeft, by a particu¬
lar attention to ofleal phyfiognomy, and the effect of
profiles and contours. His ftyle in general is forcible and
lively, although fomewhat declamatory and digreflive.
His expreflions are frequently precife, and ftrikingly cha-
rafteriftic \ and the fpirit of piety and benevolence which
pervade the whole performance render it highly intereft-
ing.
The defe6ts of the work, however, detract much from
the weight which Lavater’s opinions might otherwife
challenge. His imagination has frequently fo far out-
ftript his judgement, that an ordinary reader would of¬
ten be apt to rejeft the whole fyftem as the extravagant
reverie of an ingenious theorift. He has clothed his fa¬
vourite fcience in that affe&ed myfterious air of import¬
ance, which was fo ufual with his predecelfors, and de-
feribes the whole material world to be objects of the
univerfal dominion of phyfiognomy *. He whimfically
conceives it neceffary for a phyfiognomift to be a well-
fhaped handfome man f. He employs a language which
is often much too peremptory and decifive, difpropor-
tioned to the real fubftance of his remarks, or to the
occafion of making them. The remarks themfelves
are frequently oppofite in appearance to common ob¬
fervation, and yet unfupported by any illuftrations of
his.
Lavater certainly errs in placing too great a reli¬
ance on fingle features, as the foundation of decifion on
charafter. His opinions on the phyfiognomy of the
ears, hands, nails, .and feet of the human fpecies, on
hand-writing, on the phyfiognomy of birds, infetts, rep-
G N O M Y.
tiles, and fillies, are obvioufly premature, as hitherto no
fufficient number of accurate obfervations have been made,
in regard to either of thefe particulars, to authorife any
conclufion. He has erred in the oppofite extreme, when
treating of the important topic of national phyfiognomy,
where he has by no means profecuted the iubjeft fo far
as facts might have warranted. We muft farther take
the liberty to object to the frequent introduction of the
author’s own phyfiognomy throughout the courfe of his
woVk. His Angular remarks on his own face do not
ferve to prejudice the reader in favour of his judgement^
however much his character may juftify the truth of
them. We muft regret likewife, for the credit ef the
fcience, that the author’s Angularly fanciful theory of
apparitions fliould fo nearly refemble a revival of the an¬
tiquated opinions of the fympathifts.
To theie blemifties, which we have reluCtantly enu¬
merated, perhaps may be added that high impaflioried.
tone of enthufiafm in favour of his fcience everywhere
difplayed throughout the work of this author, which is
certainly very oppofite to the cool patient inveftigation
befitting philofophy. To that enthufiafm, however, it
is probable that in this inftance (as is, indeed, no unfre-
quent effect of enthufiafm) we are indebted for the ex¬
cellency which the author has attained in his purfuit j
and it poffeffes the falutary tendency of putting us on our
guard againft a too implicit acquiefcence in his phyfiog¬
nomical decifions.
In the Berlin TranfaCtions for 1775, there appears a jjjs
formal attack upon Lavater’s work by M. Formey. was attach-
This effay we have already mentioned. After difputing ed in the
the propriety of the extenfive fignification applied by®erl1”
Lavater and Pernetty to the term phyfiognomy, M. ^
Formey adopts nearly the fame definition which we con- Fortney,
ceive to be the moft proper, and which we have put
down as fuch near the beginning of this article. He al¬
lows that the mental charaCIer is intimately connected
xvith, and fenfibly influenced by, every fibre of the bo¬
dy ; but his principal argument againft phyfiognomy is,
that the human frame is liable to innumerable accidents,
by which it may be changed in its external appearance,
without any correfpondent change of the difpofition; fo
that it furpaffes the extent of the {kill of mortals to di-
ftinguifti the modifications of feature that are natural,
from thofe which may be accidental. Although, there¬
fore, the fcience of phyfiognomy may be founded in
truth, he infers that the Deity only can exercife it.
M. Formey further contends, that education, diet,
climate, and fudden emotions, nay even the tempera¬
ments of anceftors, affeCI the caft of human features 5
fo that the influence of mental charafter on thefe fea¬
tures may be fo involved with, or hidden by, accidental
circumftances, that the ftudy of phyfiognomy muft ever
be attended by hopelefs uncertainty. Thefe objeftions
are worthy of notice, but they are by no means conclu-
five. 18
We {hall give a fpecimen of M. Lavater’s manner of Lavater’s
treating the fubjeCl on the oppofite fide of the queftion: ™°^teinof
A fpecimen, not in Lavater’s precife words, but convey-
ing more {hortly an idea at once of his fentiments, and
of his manner of exprefling them. 19
No ftudy, fays he, excepting mathematics, more juft- Phyfiog-
ly deferves to be' termed a fcience than phyfiognomy.
It is a department of phyfics, including theology and^ ayfci, ”
belles lettres, and in the fame manner with thefe fciences ence.
may
PHYSIOGNOMY.
may be reduced to rule. It may acquire a fixed and
appropriate character: It may be communicated and
taught.
Truth or knowledge,, explained by fixed principles,
becomes fcience. Words, lines, rules, definitions, are
the medium of communication. Thequeftion, then, with
refpeft to phyfiognomy, will thus be fairly dated. Can
the ftriking and marked differences which are vilible be¬
tween one human face, one human form, and another,
be explained, not by obfeure and confufed conceptions,
but by certain charadters, figns, and expreflions ? Are
thefe figns capable of communicating the vigour or im¬
becility, the ficknefs or health, of the body; the wif-
dom, the folly, the magnanimity, the meannefs, the vir-
20 tue, or the vice, of the mind ?
Experiment It is only to a certain extent that even the experimen-
is limited tal philofopher can purfue his refearches. The adtive
m extent. anq vigorous mind, employed in fuch ftudies, will often
form conceptions which he fliall be incapable of expref-
fing in words, fo as to communicate his ideas to the
feebler mind, which wTas itfelf unable to make the dif-
covery: But the lofty, the exalted mind, which foars
beyond all written rule, which poffeffes feelings and
energies reducible to no law, muff be pronounced unfei-
entific.
Phyfiogno- admitted, then, that to a certain degree
mical truth phyfiognomical truth may as a fcience be defined and
may be de- communicated. Of the truth of the fcience there can-
fined and not exjfi a doubt. Every countenance, every form, eve-
cated toa *7 Greated exiftence, is individually diftinft, as well as
certain different, in refpeft of clafs, race, and kind. No one
length. being in nature is precifely fimilar to another. This pro-
pofition, in fo far as regards man, is the foundation-
ftone of phyfiognomy. There may exift an intimate
analogy, a ftriking fimilarity, between two men, who
yet being brought together, and accurately compared,
will appear to be remarkably different. No two minds
perfectly referable each other. Now, is it poflible to
doubt that there muft be a certain native analogy be¬
tween the external varieties of countenance and form and
the internal varieties of the mind ? By anger the mufcles
are rendered protuberant: Are not, then, the angry
mind, and the protuberant mufcles, as caufe and effedt ?
The man of acute wit has frequently a quick and lively
eye. Is it poffible to refift the conclufion, that between
fuch a mind and fuch a countenance there is a determi¬
nate relation ?
Every thing in nature is eftimated by its phyfiogno¬
my ; that is, its external appearance. The trader judges
by the colour, the finenefs, the exterior, the physiogno¬
my of every article of traffic j and he at once decides that
the buyer “ has an honeft look,” or “ a pleafing or for-
bidding countenance.”
This know- -That knowledge and fcience are detrimental to man,
ledge, how- that a ftate of rudenefs and ignorance are preferable and
vI" 3d produ<^ive of more happinefs, are tenets now defervedly
not be de- exPloded. They do not merit ferious oppofition. The
trimental extenfion and increafe of knowledge, then, is an objedt
to man. of importance to man : And what objedf can be fo im¬
portant as the knowledge of man himfelf ? If know¬
ledge can-'iinfluence his happinefs, the knowledge of
himfqlf muft influence it the moft. This ufeful know¬
ledge is the peculiar province of the fcience of phyfiog¬
nomy. To conceive a juft idea of the advantages of
phyfiognomy, let us for a moment fuppofe that all phy-
443
fiognomical knowledge were totally forgotten among
men ; what confufion, what uncertainty, what number-
lefs miftakes, would be the confequence ? Men deftined
to live in fociety muft hold mutual intercourfe. The
knowledge of man imparts to this intercourse its fpirit,
its pleafures, its advantages. 23
Phyfiognomy is a fource of pure and exalted mental ft affords
gratification. It affords a new view of the perfedtion °f ^[^^6 ~
Deity ; it difplays a new feene of harmony and beauty catior.
in his works; it reveals internal motives, which without
it would only have been difeovered in the world to come.
The phyfiognomift diftinguiihes accurately the perma¬
nent from the habitual, the habitual from the accidental,
in charadter. Difficulties, no doubt, attend the ftudy
of this fcience. The moft minute (hades, fcarcely dif- Difficulties
cernible to the unexperienced eye, denote often total op- in the flu.
pofition of charadter. A fmall inflexion, diminution, c*y-
lengthening or (harpening, even though but of a hair’s-
breadth, may alter in an aftonifliing degree the expref-
fion of countenance and charadter. How difficult then,
how impoftible indeed, muft this variety of the fame
countenance render precifion ? The feat of charadter is
often fo hidden, fo malked,-that it can only be detedted
in certain, perhaps uncommon, pofitions of countenance.
Thefe pofitions may be fo quickly changed, the figns
may fo inftantaneoufly difappear, and their impreflion on
the mind of the obferver may be fo flight, or thefe di-
ftinguifhing traits themfelves fo dflhcult to feize, that it
(hall be impoftible to paint them or deferibe them in lan¬
guage. Innumerable great and fmall accidents, whe¬
ther phyfical or moral, various incidents and paflions,
the diverfity of drefs, of pofition, of light, or (hade, tend
to difplay the countenance often in fo difadvantageous a
point of view, that the phyfiognomift is betrayed into
an erroneous judgement of the true qualities of the
countenance and charadler. Such caufes often occafion
him to overlook the effential traits of charadler, and to
form a decifion on what is purely accidental.—How fur-
prifingly, for inftance, may the fmallpox disfigure the
countenance, and deftroy or confound, or render imper¬
ceptible, traits otherwife the moft decifive ? 2 -
We (hall, then, continues Lavater, grant to the op-May one
pofer of phyfiognomy all he can a(k 5 and yet we do not day be ob-
live without hopes that many of the difficulties (hall be viatcd-
refolved which at firft appeared inexplicable. 2(j
He then proceeds to a fpecific illuftration of his fub- The nature
jedf under a great variety of titles, in which he treats of of Lavater’s
human nature in general, and of each particular feature work-
feparately.
To enumerate the different divifions of his book would
not be more fatisfadiory to our readers than the perufal
of the contents of the book itfelf; and an attempt to
epitomize even the effential fubftance of the vaft multi¬
plicity of matter contained in his effays, (which are yet
only fragments, and to which indeed he himfelf does not
pretend to give any higher appellation), would extend
this article to a difproportionate length. Such an
abridgement, after all, would convey no folid informar
tion on a fubjedt which merits all the time and ftudy
that an attentive perufal of Lavater’s works at large 2-
jyould require.^ Probable
From the hiftorical dedudlion of the literary progrefs caufes of
of phyfiognomy which we have thus attempted to laythe d!fre-
before our readers, it appears, that although the fcience whisJTthis
has fallen into difrepute, there can fcarcely be mention- fcience has
3 K 2 cd fallen.
444
28
There is a
relation be¬
tween the
difpofitions
of the mind
and the fea¬
tures of the,'
face.
29
Craniognc-
mic fyftem
ef Dr Gall.
PHYSIO
ed a period in which any cultivation of fcience took
place when phyficgnomy was not likewife the ftudy, nay
ibmetimes even the piofeffion, of men of the moft emi¬
nent abilities and the greateft learning.
The reafons why at prefent fo little attention is paid
to the fubjeft probably are,
1 ft, That it has been treated in conjunction with fub-
jebts now with propriety exploded : And,
2dly, That it has been injured by the injudicious af-
fertions and arguments of thole who have undertaken its
defence.
Sometimes, however, the wife and the learned may
err. The ufe of any thing muft not be rejected for no
better reafon than that it is capable of abufe. Perhaps
the era is not diftant when phyliognomy ftiall be rein-
ftated in the rank which (he merits among the valuable
branches of human knowledge, and be ftudied with
that degree of attention and perfeverance which a fub-
ject deferves fo effentially connebted with the fcience of
man.
That there is an intimate relation between the difpo-
fttions of the mind and the features of the countenance
is a fabl which cannot be queftioned. He wdio is fink¬
ing under a load of grief for the death of an affectionate
wife or a dutiful child, has a very different call of fea¬
tures from the man who is happy" in the profpect of
meeting his miftrefs. A perfon boiling with anger has
a threatening air in his countenance, which the moft
heedlefs obferver never miftakes j and if any particular
difpofition be indulged till it become habitual, there
cannot be a doubt but that the correfponding traces
will be fo fixed in the face as to be difcernible by the
Ikilful phyfiognomift, under every effort made to dif-
guife them. But when we attempt to decide on a man’s
intelleblual powers by the rules of this fcience, wre are
often deceived } and in this refpeft we have reafon to
believe that Lavater himfelf has fallen into the groffeft
miftakes.
Connected with phyfiognomy, we may confider the
craniognomic fyftem of Dr Gall of Vienna, which is fo
called, becaufe, from the exterior form of the cranium,
he infers the powers and difpofitions of the mind. The
brain, he obferves, is the material organ of the abtion of
the mind ; and as it increafes in direct proportion to the
faculties of animals, he has endeavoured to prove, that
the faculties are diftinbt and independent on each other j
that each has its proper material organ, and that the
■expanfion of the organ is in proportion to the ftrength
of the faculty. This fyftem is attempted to be eftablifh-
ed by the following reafoning.
“ The internal faculties, (faysDr Bojanus, the author
of a view of this fyftem), do not always exift in the fame
proportion to each other. There are fome men who have
a great deal of genius without having a memory, who
have courage without circumfpeftion, and who poffefs a
metaphyfical fpirit without being good obfervers.
“ Befides, the phenomena of dreaming, of fomnambu-
lifili, of delirium, &c. prove to us that the internal
faculties do not always acft together *, that there is of¬
ten a very great ablivity of one, while the reft are not
fenfible.
“ Thus, in old age, and fometimes in difeafe, fuch,
far example as madnefs, feveral faculties are loft, while
others fubfift j befides, a continued employment of the
fame faculty fenffbly diminiihes its energy; If we em-
G N O M Y.
ploy another, we find it has all the force of which it is
fufceptible $ and if we return to the former faculty, it is
obferved that it has refumed its ufual vigour. It is thus
that, when fatigued with reading an abftrabt philofophi-
cal work, we proceed wdth pleaiure to a poetical one,
and then refume with the fame attention our former oc¬
cupation.”
“ All thefe phenomena prove that the faculties are
diftinbl and independent of each other, and we are in¬
clined to believe that the cafe is the fame with their ma¬
terial organs.”
“ [We do not entirely agree with this idea of Dr
Gall, and we believe, on the contrary, that the fepara-
tion of the material organs ought to be confidered as the
caufe of the diftinbtion of the internal faculties. It ap¬
pears, to us at leaft, that by fuppofing the faculties
themfelves as originally feparated, we cannot fave our-
felves from falling into materialifm, which exifts when
the mind is no longer confidered as unity.]
. “ The expanfion of the organs contained in the cranium
is in the direft ratio of the force of their correfponding
faculties”
“ This principle, diblated by analogy, refts on this
axiom, that throughout all nature the faculties are al¬
ways found to be proportioned to their relative organs }
and the truth of it is proved in a fpecial manner by the
particular obfervations of Dr Gall.
“ It is however to be remarked, that exercife has a
great influence on the force of the faculties, and that an
organ moderately expanded, but often exercifed, can
give a faculty fuperior to that which accompanies a ve¬
ry extenfive organ never put in abtion j as we fee that a
man of a w^eak conformation acquires, by continued ex¬
ercife, ftrength fuperior to another of a more athletic
ftrubture.”
“ [We muft here mention an opinion wdiich feems to
refult immediately from this principle, and which, how¬
ever, is falfe : It is, that the volume of the brain, in ge¬
neral, is in the direbt ratio of the energy of its faculties.
Obfervation has proved to Dr Gall, that we cannot
judge of the ftrength of the faculties but by the deve-
lopement of the feparate organs which form diftinbt emi¬
nences in the cranium ; and that a cranium perfebtly
round, of wdiatever fize it may be, is never a proof of
many or of great faculties.]
“We do not recollebl to have heard the reafon afiigned
by Dr Gall •, but, in our opinion, thefe brains may be
confidered as in a ftate analogous to obefity ; and as we
do not judge of the mufcular force of a man or an ani¬
mal by the volume of their members, but by the deve-
lopement of the mufcles in particular, one would think
we ought, in like manner, to judge of the ftrength of the
faculties by the developement of the relative organs.
“ In the laft place, the 4th principle, the moft im¬
portant for prabtice in regard to the fyftem of Dr Gall,
is:
“ IVe may judge of thefe different organs and of their
faculties by. the exterior form of the cranium.
“ The truth of this principle is founded upon another,
viz. that the conformation of the cranium depends on
that of the brain •, a truth generally acknowledged, and
proved by the anterior part of the brain, by the impref-
fions in the anterior part of the cranium, and by other
fabts.
[There are fkulls, it is ttue, in which an external
protuberance
445.
PHYSIOGNOMY.
protuberance of the bone correfponds to an interior one j
and this irregularity, which is found fometimes as a dif-.
eafe, and molt commonly at an advanced age, when the
cerebral organs do not oppofe the fame refiftance to the
cranium, renders the practice of Dr Gall’s fyltem, in
fome meafure, uncertain.]
“ Guided by thefe principles, Dr Gall examines the
nature of the Ikull, compares the crania of animals and
thofe of men analogous and different in faculties. His
refearches have proved to him, in a manner almoft in-
conteltable, not only the above truths, but that the fa¬
culties of animals are analogous to thofe of man j that
what we call inilinct in animals is found alfo in the lat¬
ter, fuch as attachment, cunning, circumfpeftion, cou¬
rage, &c. ; that the quantity of the organs fixes the
difference of the genus of animals, their reciprocal pro¬
portion that of individuals; that the difpofition original¬
ly given to each faculty by nature may be called forth
by exercife and favourable circumftances, and fometimes
by difeafe, but that it never can be created in the cafe
where it has not been given by nature (c) j that the ac¬
cumulation of the organs takes place in a conftant man¬
ner from the hind part forwards, from the bottom to
the top, in fuch a manner, that animals in proportion
as they approach man in the quantity of their faculties
have the fuperior and anterior part of the brain more ex¬
panded j and, in the laft place, that in the moft perfeft
animal, man, there are organs in the anterior and fupe¬
rior parts of the frontal bone, and of the parietals, def-
tined for faculties which belong to them exclufively.
It is under the latter point of view that the difcoveries
of Dr Gall agree perfectly with the theory of the facial
angle, which feems Hill further to eftablilh the truth of
them.”
Moll of our readers will probably be fatisfied with the
fliort view which we have now given of this fanciful and
vifionary fyftem *, but fuch as with for a fuller expofition
of it, may confult the Philofophical Magazine, vol. xiv.
p. 77. from which the above is extracted. We thall on¬
ly add the names of a few of the organs, which the au¬
thor of the fyffem thinks he has difcovered. Organ of
the tenacity of life. Organ of mufec. Organ of fight¬
ing. Organ of murder. Organ of cunning. Organ of
arithmetic. Organ of thieving, &c.
PHYSIOLOGY.
INTRODUCTION.
Definition I* T>HYSIOLOGY is that part of phyfical fcience
and objedls which treats of the nature, properties, and func-
of phyfiolo- tions of living bodies 5 comprehending under this term,
§y' animals and vegetables. The word is derived from
(puc-if, “ nature,” and Aoy#?, “ a difcourfe 5” and figni-
fied originally what we may call natural knowledge.
The objeft of this fcience is to examine and compare
the phenomena of life } to difcover the properties,
powers, and operations of the bodies that are actuated
by this principle, and to purfue the developement, pro-
grefs, and decay of vital energy, from brute matter,
which poffeffes no portion of vitality, to the moft perfect
animal, which feems to have it in the greateft perfec¬
tion.
2
Divifions.
Hiftorical
phyfiology.
4
Philofophi¬
cal phyfio-
logy.
2. Phyfiology may be confidered under three heads ;
hifiorical, philofophical or rational, and practical phyfi¬
ology.
3. Hi/lorical phyfiology is occupied in giving a Am¬
ple relation of the fadfts and phenomena that take place
in living bodies; in bringing them together, and com¬
paring thofe which fucceed each other without interrup¬
tion during the exiftence of vitality.
4. It is the bufinefs of philofophical phyfiology to
confider the nature of thele phenomena, and endeavour
to deduce from them fome general conclufions, by which
they may be explained or elucidatedto draw from
them natural confequences, and unfold fucceflively their
analogies and relations ; to arrange, diftribute, and claf-
fify them, and thus acquire fufficient data by which to
difcover the caufes which produce them.
The praElical part of phyfiology is intended to point pra(^fcap
out the application of the principles of the fcience to the pjiyf10i0gy.^
ufeful purpofes of life, efpecially to medicine and agri¬
culture. Of thefe divifions the firft is the moft import¬
ant, as, until we have acquired a pretty complete know¬
ledge of the fa£ts relating to living beings, and arranged
thefe in a natural manner, it cannot be expelled that we
(hould make any great progrefs in explaining them, or
inveftigating their caufes. From the multitude, variety,
and complex nature of thefe phenomena, a complete
view of them is extremely difficult, and requires the
united efforts of genius, dexterity, patience, and dif-
cernment. ^
Phyfiology is intimately related to feveral other de- Relations to
partments of natural knowledge. Its relation to ana- anatomy,
tomy is the moft ftrift and natural ; and indeed the
knowledge of the ftrufture of living bodies is a neceffary
introduflion to that of their properties and funftions. So
clofe is the union between thefe two fciences, that it is
generally thought that the ftudy of them ffiould go hand
in hand. Certain it is, that, without phyfiology, ana¬
tomy is a dry and uninterefting ftudy 5 while, on the
other hand, phyfiology, unaided by anatomy, is obfcure
and uncertain. It is by means of anatomy that we learn
the ftrufture and organization of the animal machine ;
the difpofition and form of its feveral members; the
parts that concur in the compofition of them ; the ar¬
rangement and the connection of thefe : it is by means
of anatomy that we know how to eftimate the advanta¬
ges
(c) The germ of every organ muft exift in embryo, if the expanfion of that organ is to be afterwards called
forth.
44'6
Introduc¬
tion.
chemiitry,
8
mechanical
philofophy,
9
metaphy-
fics.
PHYSIOLOGY.
ges of any particular confotination j that we eftimate
the proportion between the folid and fluid parts of the
body, and the adaptation of the organs to the various
ufes for which they are deltined. Eut we mutt remem¬
ber, that the aid of anatomy in phyfiological refearches,
extends no farther than to the mechanical arrangement
and relation of the feveral parts of the body j it teaches
us nothing of its intimate compofition, and much lefs
does it inform us refpedting the vital powers and mental
energies difplayed by the living body. The moft accu¬
rate infpection of the brain will afford us no light re-
fpefting the obfcure fundlion of fenfation, and the hid¬
den operation of thought and judgement } nor will the
niceft diffe£tion of the eye, or of the tongue, fhew lis
how the former is enabled to convey to us the ideas of
external obje-fli*, w how the latter imparts to us the
thoufand varied flavours of fapid bodies. In fhort, we
may conclude, that the more the exercife of any func¬
tion depends on the ftrufture and organization of the or¬
gans that perform it, the more capable is it of illuftra-
tion from anatomy.
The fcience of chemrftry. has proved of eminent ufe
in explaining feveral fundlions of the animal economy,
which, without its afliftance, would have been very im-
perfecfliy underltood. The aftion of the air on the
blood during refpiration, and the digeltion of food in the
llomach, are found to depend chiefly on chemical ope¬
rations 5 while this fcience has explained to us, in a moft
fatisfaftory manner, the nature, compofition, and reci¬
procal asftion of the component principles of organized
beings, and the nature of feveral changes which they
undergo, both in the living and the dead ftate. But if
we extend the application of chemiftry too far, and ima¬
gine, as fome of our modern chemical phyfiologifts have
done, that it is capable of explaining I'fe, motion, and
even fenfation, we ftxall only betray our own prefumption
and our ignorance of vital phenomena. When the per¬
formance of any fundlion depends on the intimate com¬
pofition of its organs, or the combinations and decom-
pofitions that take place among their component prin¬
ciples •, then, and then only, is itfufceptible of chemical
illuftration.
Mechanical philofophy is employed with advantage
in explaining fome of the phenomena that take place in
living beings. The ftrength and folidity of the bony
compages } the force and direction of the mufcular mo¬
tions ; the propagation, direction, and mechanical effect
of light, found, odours •, the effefts of the gravity and
elafticity of atmofpheric air, and a few other circum-
ftances, may be fubmitted to calculation, and illuftrated
on phyfical principles: but the laws of mechanical and
of vital aftion are, in general, fo different, and even
the moft mechanical phenomena of living beings are of¬
ten fo modified and counterafted by the agency of the
vital powers, that, on the whole, we muft confider ge¬
neral phyfics as one of the leaft ufeful auxiliaries of phy¬
fiological refearches.
Of all the branches of phyfical fcience, phyfiology
certainly makes the neareft approach to the region of
metaphyfics ; but yet there is a diflerence between thefe,
though it may not be very eafy to point out the precife
line of termination. Phyfiology, as already defined, be¬
ing that fcience which has for its objeft the organical
economy of living bodies, the word organical, we think,
here fhould mark the diftin&ion.
3
Whenever the economy of living bodies indicates de- Introdue-
fign, and cannot refult from any combination or ftruc-, tlon-
ture of organs, it muft befuppefed the'effect of fome-
thing diflerent from matter, and whole explanation be¬
longs to that fcience which is called metaphyfcs, or which
we might term the philofophy of the mind. By afcribing,
indeed, to the glandular contents within the cranium,
and to that fiction animal fpirits, the motives of aftion,
the fuperficial and ill-informed may have been led to
an opinion that perception, memory, and imagina¬
tion, are the funftions of the cerebrum, the medulla ob¬
longata, and cerebellum ,• that the foul is a confequence
of organization ; and the fcience which treats of it only
a particular branch of phyfiology. But mind and its
faculties are now fo well underftood and inveftigated,
that this opinion can feldom prevail but where penetra¬
tion is not remarkable for its acutenefs, or where re-
fleftion, reading, and refearch, have long been confined
within the limits of a narrow circle.
Some metaphyfical phyfiologifts contend, that every
living fyftem of organs fuppofes mind, and indeed in the
ftudy of fuch fyftems the phyfiologift muft often meet
with many phenomena that are lefs Angular than Ample
perception, and yet for which he cannot account by any
knowledge he poffeffes of organic powers. This truth
we partly acknowledge, when, like ancient Athens creel¬
ing her altars to unknown gods, we retreat to thofe
afylums of ignorance, the vis infta, the vis nervea, the
vis vitalis, the vis tnedicatrix, and a number of others of
the fame kind. r r
Phyfiology, in the general fenfe in which we have and natural
defined it, is a fcience that inveftigates the nature andhiftory.
the fun&ions of all living beings. It is, therefore, rea-
fonable to fuppofe that it muft have an intimate connec¬
tion with natural hiftory, and in faft, it is to this branch
cf phyfics that it has been perhaps more indebted than
to any other. A comparative view of the various gra¬
dations among organized beings has taught us to appre¬
ciate the value of the feveral funflions that charafterife
vitality, and has fnewn us, that in' proportion as the
ftrufture is more complex, the fundlions are more nu¬
merous, and more complete. Repeated obfervations,
and multiplied experiments on various tribes of anima¬
ted nature have cleared up many doubtful and obfcure
phenomena in the economy of man, and a continuation
of this truly philofophical method of refearch promifes
to place phyfiology on the folid bafis of experience, and
enable us to reafon, where only we can reafon with fafe-
ty, by a deduction from fa£ts. The more numerous
thefe fatfts, and the more complete their arrangement,
the more extenfive, and the more fecure will be the
foundation which they afford for phyfiological conclu-
fions.. In fhort (to ufe the language of Dumas, who
has illuftrated this relation at great length), “ the phy¬
fiologift who is converfant with natural hiftory, is fo
much the better fortified againft uncertain opinions in-
afmuch as he has more fully obferved the operations of
nature in conneffion and in detail. An hypothefis
which to others appears perfedlly adequate to the object
in view, is not convincing to him. He rifes above the
particular objeft to which it is accommodated, in order to
appreciate its value; and it is often among circumftances
which are foreign to the original fubjeft, that he feeks
for exceptions or contradictions that overturn the hypo-
thefis. Every thing that may ferve to complete the
knowledge
P H Y S I
Introchic- knowledge of the animal economy enters into his plan j
tion. anc} as the nature of man is fo much the lefs incompre-
henfible as wre employ a greater number of compara-
* Dumas t;ve jdeas in its expofition, it is doubtlefs in the power of
rnph^io natural hiftory to elucidate that fubjecf, by revealing a
/os-;> multitude of unknown relations between man and thofe
i.p. 231. beings which referable or which differ from him.*,,
11 The importance and utility of phyhology will fcarce-
Importance p.g qUefti0ned, and need therefore but little illuftra-
ofphyfiolo- tion. To all who defire to become acquainted with
gy. the operations that take place in the animal economy,
or to trace the progrefs of vegetation, and examine the
various changes produced on the feed or bud from the
adffion of air, heat, and moifture, (and what ftudies can
be more deferving of a rational and an enlightened
mind ?) phyfiology muff afford the mod interefting fub-
jedls of contemplation. To the anatomift and the bo-
tanift, it relieves the tedium of dry defcription andfevere
claffiffcation •, to the phyfician it holds out the fureft lights
to direft his refearches into the circumftances that are
favourable to life and health, into the nature and pheno¬
mena of death, and of courfe, the means of avoiding or
delaying its attack ; to the agricultuvift it furniffres fome
of the moft certain principles to diredt him (with the
aid of chemiftry) in the choice of foils, and the applica¬
tion of manures ; while to the genuine naturalift, no
fubject prefents fuch a field of amufement and inftruc-
tion. When it (hall have been rendered as complete
as the ftate of contemporary fcience will allow, it will
exhibit the general refult of all thofe experiments and
obfervations that have purpofely been made to illuftrate
the phenomena of animated matter, or have accidentally
contributed to that illuftration ; and when it fhall reach
that fummit of perfettion to which the efforts of genius
may carry it, it may diffufe a light, of which at the pre-
fent day we can form no juft or adequate conception.
On many occafions it may introduce order for confu-
fion, certainty for doubt; and may eftablUh fcience, in
various departments that are now occupied by fancy and
conjefture.
After having pointed out the nature, divijions, rela¬
tions, and utility of phyfiology, it may not be improper
to make a few remarks on the beft methods of purfuing
the ftudy of it, and the works that are moft worthy of a
perufal.
Methods of From what has been faid of the relations between
{tidying phyfiology and other fciences, it will be inferred that
phyfioiogy. the ftudent of our prefent fubjeft fbould come prepared
with a moderate flrare of knowledge in anatomy, both
human and comparative, of chemiftry, of mechanical
philofophy, efpecially dynamics, optics, pneumatics,
and acouftics; and natural hiftory, efpecially zoology
and botany. At leaft the rudiments of thefe branches
ftrould be well underftood, and the ftudent will then
, have laid a foundation on which to raife a firm and du¬
rable fuperftrutture.
He has now to make himfelf acquainted with what is
already known •, and in this inquiry it is of much confe-
quence that he ftrould felect thofe works that embrace
the whole fubjeft, without being too diffufe on the one
hand or too brief and general on the other. The Ele-
menta Pht/Jiologiee of Haller contains a mafs of informa¬
tion that will ever render it valuable as ?a book of re¬
ference, though it will fcarcely at the prefent day be
ftudied as a fyftem of phyfiology. His Primes Linecc
1 L G G Y. 447
Phyfiologi.ee, though firft written, is chiefly a com- Ir‘^l,c‘
pendium of the larger work, and is better adapted 
to the general ftudent, though, from its not containing
the later difcoVeries in the icience, it is far from com¬
plete. The Injlitutiones Phyjiologiee of Bluiyenbach is
a ufeful work, though it has now given place to the later
and more accurate publications oi Cuvier and Dumas.
The Anatomic Comgarce of the former writer contains an
excellent digeft of comparative phyfiology, and the pre¬
liminary oblervations prefixed to the anatomical details
contained in this work, may be read with ccnfiderable
advantage. Probably, however, the Principes de Phy-
fiologie of Dumas is the moft perteft and fcientific mo¬
dern production that has appeared on the fubjeft. We
cannot fay fo much of the Elements of Phyfology late¬
ly publiftied by Richerand, and tranflated into Engliftv
by Mr Kerrifon; for although it contains confiderable
information, and a great difplay of reading, and even of
original obfervation and experiment, it is neither fcienti¬
fic nor always very accurate. The works of Bichat,
efpecially his Anatomie Generale, Anatomic Defcriptive^
and his Rcc here lies Phyjiologiques fur la Vie et la Mart,
abound with excellent phyfiological remarks, and, allow¬
ing for the great extenCto which he has carried fome pe¬
culiar doctrines, are among the beft that have appeared
on the animal economy.
In our own country, we have many valuable treatifes
and papers on different parts of phyfiology, and the
names of Hunter, Monro, Home, Cooper,' Abernethy,
Carlifle, Sanders, Barclay, Jones, and many others, will
ever refleft honour on the country and on the age.in
which they lived. We can fcarcely, however, point
out a complete work in our language on the general --
fubjecf of phyfiology, though we doubt not that many
will be difpofed to confider the Zoonomia of Dr Darwin
as entitled to that appellation. We allow7 that this is a
ftupendous monument of the genius and induftry of its
author, and it contains an ample ftore of valuable fafts,
winch, if they could be diverted of the hypothefis with
w'hich they are fo much blended, wmuld be extremely
ufeful to the caufe of phyfiological fcience. At prefent
many of them tend to miflead, by a ftiew of metaphyfi-
cal acutenefs, and by the new fenfe in which feveral
terms are employed. Another of Dr Darwin’s wmrks,
not lefs valuable, in a phyfiological point of view, is his
Phytologia, in which he treats of the economy of vege¬
tation with ability and fuccefs.
He who is defirous of advancing and improving the Means of
fcience of phyfiology, muff, in the firft place, have re- advancing
courfe to a patient, and, as far as may be, an accurate ancl !mJ'
obfervation of the phenomena that take place in or-
ganized beings 5 but the multitude, the variety, and
complicated nature of thefe phenomena, place in his way
obftacles that it is difficult to furmount. It is only
through time, and patience, and affiduity, that he can <
attain his object ^ and it requires confiderable dexterity
and acutenefs to detedf the appearances under which
thefe phenomena fometimes prefent themfeJves, to pierce
through the obfeurity in which they are often involved,
and to avoid, in a route fo uncertain, both the illufions of
fenfe and the errors of genius. The living body has
properties peculiar to itfelf, wffiile it alfo poffeffes others
that are common to it with brute matter. The pheno¬
mena by which it manifefts thefe two orders of proper¬
ties, are therefore of tw7o kinds, as they relate particu¬
larly ,■
448
Introduc-
14
Obferva-
tion.
Experi¬
ment.
Cautions.
larly to the 'Itate of vitality, and as they are found in
every object that exifts. Thefe latter are fubjeft to
the general laws of matter, are confounded with the
phenomena of univerfal nature, and may be denominated
phyfical phenomena. Among the former, fome are con¬
fined to the arrangement or difpofition of the parts in
organs, and depend on the ftrudture or form of thefe
organs. Thefe may be called organic phenomena.
Others depend on the particular laws that govern vital
beings, and are not the refult of any peculiar organiza¬
tion •> thefe are vita/phenomena.
Obfervation alone is fufficient to indicate the prefence
or the exiftence of thefe phenomena $ but to unveil
them fully there is required an unceafing attention,
that is refolved to purfue them through the changes pro¬
duced by age, fex, climate, fituation, and all thofe cir-
cumftances that can affe£t the living fyftem.
To obfervation, he muft add, wherever this can be
done with a chance of accuracy, a patient inveftigation
of nature by experiment. From the experiments of
Spallanzani and Stevens on digeftion \ of Goodwin,
Menzies, Spallanzani, and Davy on refpiration j of
Monro, Galvani, Volta, and a hundred others on ani¬
mal irritability, with many other experiments made both
at home and abroad, more light has been thrown on
the economy of living bodies, than by all the hypothefes
and theories that the molt ingenious fpeculatifts have
contrived fince the firft dawn of infant fcience.
In following out Bacon’s great plan of obfervation
and experiment, we muft, however, take care in phyfi-
ological, as in all other phyfical inquiries, not to be too
hafty in our conclufions, and not to fuppofe that we
have reached the bottom of the well of truth, when we
have barely got within its verge. Further obfervations
on this fubjeft are unneceffary here, as we have already
treated it at fome length in the articles Philosophy and
Physics. . \
We (hall conclude thefe introductory remarks with
a brief Iketch of the principal arrangements of modem
phyfiologifts, and a tabular outline of the fubjeCt as we
propofe to treat it in the following pages.
Twi/modes There are two modes of arrangement that have ufual-
of arrange- ly been adopted in treating phyfiology j one according to
ment. the order of the funftions, and another according to that
of the organs by which thefe are performed. The latter
of thefe was adopted by Haller •, the former is that of
l9 Damas, Cuvier, and moft of our later phyfiologifts.
Dumas, after a long introductory difeourfe, in which
he treats of the beft method of purfuing the ftudy of
anatomy and phyfiology, divides his fubjeCt into fix
parts. In the firft of thefe he offers fome general views
refpeCting anatomy, phyfiology, and all the branches of
phyfics which are employed in illuftrating the nature
and properties of organized and living beings. In this
part he gives a compendious hiftory of the progreflive
improvements in anatomy and phyfiology, points out
the relations that take place between thefe fciences, and
the auxiliary branches of mathematics, mechanical phi-
lofophy, chemiftry, and natural hiftory ; he confiders
the principal differences that diftinguifh organized from
inorganic matter; the nature, effeCts, and duration of
life, and of the general and particular powers or facul¬
ties of nature, both in living and brute matter.
In the fecond part he lays down the fundamental
principles on which the phyfical conflitution and parti-
4
17
Modern
arrange¬
ments.
Arrange¬
ment of
Dumas.
PHYSIOLOGY.
cular economy of man depend $ treats of man confider- Introduc¬
ed individually ; of his formation, ftruCture, and varie-, tlon- .
ties $ of the modifications produced in the nature of man v "
by age, fex, habit, and temperament: of the relations
between man and external objeCts j of the aCtion and re¬
action of the organic fyftems on each other j of the or¬
ganic ftruCture of man, and of its feveral varieties in the
different parts and organs j of the natural compofition
of the different fluids and folids of the human body : and
gives a methodical divifion of the functions, with a criti¬
cal examination of the modes of claflification commonly
received.
In the third part he treats of the phenomena of the
animal economy, in the relation which they bear to the
perpetual commerce eftablifhed between man and the
organs that furround him, ©r of fenfation and motion.
Here he confiders the aCtion of external objeCts upon
man, whence refult the phenomena of fenfation, and the
aCtion of man on external objeCts, from which arife the
phenomena of motion.
In the fourth part he treats of the phenomena of the
animal economy, in the relation which they bear to the
confiftence of the fluids, the cohefion of its folids, and
the temperature of the whole fyftem. Here he con¬
fiders the mutual aCtion between the veffels and the
blood, from which refult,'both in the folids and fluids,
that degree of cohefion and pliability that favours the
neceffary expanfibility of the living body, or the func¬
tion of circulation •, the aCtion of the air, and of caloric,
on the folids and fluids, from which refults the degree of
expanfion neceflary to life, or the funCtion of refpiration.
In the fifth part he treats of the phenomena of the
animal economy in the relation which they bear to the
healthy and entire ftate of the material fubftance and
compofition of the body. Here he confiders the aCtion
of alimentary fubftances on the human body, in repair¬
ing its lofs, and preferving its fubftance, from which
refult the phenomena of digeftion, abforption, and
nutrition; and of the aCtion of certain organs on the
fluids of the body, in feparating thofe which do not ferve
the purpofes of nutrition, from which refult the pheno¬
mena of fecretion and excretion.
In the fixth and laft part, he treats of the phenomena
of the animal economy in the relation which they bear
to the commerce eftablilhed between the individual and
the fpecies. Here he confiders the mutual phyfical ac¬
tion of the two fexes, from which arife the phenomena
of generation j and the mutual moral aCUon of feveral
individuals, from which refult the phenomena of fpeech,
and mutual intelligence.
From this fketch of the arrangement of Dumas it
will be feen, that although he takes a very extenfive
view of the fubjeft, his obfervations are chiefly confined
to the human body. . 20
Though the leClures of Cuvier do not contain a Anangt-
complete fyftem of phyfiology, the anatomical matter in
them is, however,, fo much blended with obfervations on *vier‘
the animal economy, that it will be of importance for
the phyfiological ftudent to be acquainted with his ar¬
rangement.
The \vhole work is divided into 30 leClures : the firft
of which is occupied with preliminary obfervations on
the animal economy, comprehending a general view of
the funClions of animal bodies *, a general idea of the
organs of which the animal body is compofed j a view
of
V
P H Y S I
Introduc- of the principal differences exhibited by thefe organs,
. tion- and of the relations which exift among thofe variations,
y together with a divilion of animals founded on their or¬
ganization. The fecond lefture treats of tire organs of
motion in general 5 the third, fourth, fifth, and fixth
ledures are merely anatomical, exhibiting a comparative
view of thefe organs in the feveral claffes of animals.
The feventh ledure is llridly phyfiological, and treats
of the organs of motion confidered in the 1'everal adions
of Handing, walking, feizing and climbing, leaping,
fwimming, and flying.
The eighth, ninth, tenth, eleventh, twelfth, thirteenth,
fourteenth, and fifteenth ledures, are occupied in con-
fidering the anatomy and phyfiology of the fundion of
fenfation. Of thele, part of the ninth treats of the
nervous fyftem in general, and of its adion j part of the
twelfth gives the phyfiology of vifion ; part of the
thirteenth, that of hearing ; part of the fourteenth, that of
touch; and part of the fifteenth, that of fmell and tafte.
The fixteenth, feventeenth, eighteenth, nineteenth,
twentieth, and twenty-firll ledures treat of the organs
and phenomena of digeltion, maftication, infalivation,
and deglutition. The twenty-fecond ledure treats of
what have been called the aflirtant chylopoietic vifcera,
namely, the liver, the pancreas, the fpleen, and their
offices. The twenty-fourth treats of the organs and
phenomena of circulation in general j the twenty-fixth
of thofe of refpiration in general j the twenty-eighth of
the organs of voice.
O
The twenty ninth treats of the organs and phenome¬
na of generation, and the thirtieth, of thofe of excretion,
comprehending a general view, both of fecretion and ex-
aI cretion.
Of Bichat. Subjoined to Bichat’s introdudion to his Anfltonne
Genera/e, there is a tabular view of phyfiology, in which,
after fome preliminary outline of the general ftrudure of
the organs and of the phenomena of vitality, he divides
the fundions into claffes, orders, and genera.
The firft clafs confifts of the fundions that relate to
the individual j the firft order of which, comprifing the
fundions of animal life^ comprehends five genera, viz.
fenfations^ cerebral funBions, locomotion, voice, and ner¬
vous tranfmijjion, befides Jleep. The fecond order of this
clafs contains the fundions of organic life, and compre¬
hends eight genera, viz. digejlion, refpiration, circulation,
exhalation, abforption,fecretion, nutrition, and color f cation.
The fecond clafs contains the fundions that relate to
the fpecies in general, and is divided into three orders.
The firft of thefe, comprifing the fundions peculiar to
the male, comprehends only one genus, viz. the produc¬
tion of the feminal fluid. The fecond comprises the
fundions peculiar to the female, and contains three ge¬
nera, viz. menflruation, the production of milk, and of the
female generative fluids. The third order comprifes the
fundions that relate to the union of the two fexes, and
the produd of that union ; and it comprehends alfo three
genera, viz. generation, geflation, and delivery.
Refpeding the peculiar dodrines of this writer wre
23 fhall fpeak hereafter.
Zoological There is ftill another mode of arranging the pheno-
mena living bodies, that deferves to be noticed, name¬
ly, that in which they are arranged according to the ar¬
tificial fyftems of natural hiftory. This mode of ar¬
rangement, though of infinite advantage to the zoolo-
VOL. XVI. Part II.
O L O G Y,
gift, by (hewing him at ohce the extent of his fubjed, Introduc-
and giving to his memory a power of recolledion which tion-
it could not otherwife poffefs, is yet not fuch as the phy- ' v'^'
fiologift would wifh to be oblerved. Zoological" ar¬
rangements are ufeful chiefly as they facilitate ffie ftudy
of the manners, difpofitions, and habits of different ani¬
mals j and all that part of the outward economy which
indicates fomething of the wffdom and defign difplayed
by the Creator, in their ftrudure and adaptation to the
modes of life which they are intended to purfue ; but
they do not _ fufficiently illuftrate the internal fti udure
on which this outward economy depends, nor do they
fufficiently explain the more lecret fundions, which be¬
ing independent of the will of the creature, only dif-
play the power and ommicience of him who made it.
This will be readily conceived from confidering the dif¬
ference between zoology and phyfiology, as we have de¬
fined it. Zoology is chiefly led 10 examine the animal
kingdom as it dually prefents itfelf to the eye, includ¬
ing a great variety of objeds 5 phyfiology examines on¬
ly that part of the animal economy which is principally
made known by anatomy and chemirtry. Zoology has
been accuffomed to divide its kingdom into^ lo many
claffes or orders of animals ; phyfiology would naturally
divide its economy into fo many fundions. Zoology
has ufually fubdivided its claffes by certain obvious ex¬
ternal marks, as the teeth and claws j phyfiology woulff
naturally fubdivide its fundions by the varieties of thofe
organs which are deftmed to perform them, as the fe¬
veral kinds of lungs and ftomachs. Zoology mentions
the fundions only in a curfory manner, as forming a
part of the hirtory of animals $ phyfiology takes notice
of animals, only when they are of ufe to illuitrate the
fundions. To the(e differences we may add another j
that phyfiology, in the extended fenfe which we have
given it, goes beyond zoology in comprehending the
economy of the vegetable creation. From this compari-
fon it will be admitted, that things which are primary
in a zoological method, will often be fecondary in a
phyfiological arrangement, and vice verfa. This is very
confpicuoufly the cafe in one of the grand divifions of
Linnaeus, viz. mammalia, where the important lecretory
organs of the milky fluid are noticed only like the
colour of the hair, or the length of the tail, as a good
outward mark of diftindion, and likewife in the excel¬
lent table by D’Aubenton in his introdudory view of na¬
tural hiftory, in the Encyclope'die Methodiyue, in which
the fundion of digeftion is not even mentioned.
It is, however, extremely ufeful, both to the natural- utility
ift and phyfiologift, that the arrangements of bothofthe applii
fciences ftiould be, as far as poflible, adapted to each tat’on
other, by marking the relative importance of the feveral l’hyfioloSi"
fundions in the various claffes ofliving beings. 'j'i1jsfaltiozoolo-
has been very ably performed by Vicq d’Azyr, a modi- fangement.
fication of whole table has been given in the compara¬
tive part of our Anatomy. See Vol. II. p. 280.
With refped to all phyfiological arrangements we
may obferve, that as the phenomena ofliving beings ate
fo intimately dependent on each other, as to form the
links of one continued chain, it is of little confequence
which of the fundions or phenomena we make the point
from which we fet out in our examination. But as the
organs of fenfation in moft a> imals, and thofe of digef¬
tion in almoit all living creatures, are among the firft
3 that
24
PHYSIOLOGY.
45°
Introduc- that are evolved, it appears moft convenient to begin
, tl°n- with one of thefe. The following is the arrangement
^ that we ihall adopt in the prefent article.
Arrange- After giving a fketch of the progrefs of phyfiological
mentofthe difcoveries and opinions, we fhall divide the remaining
prefent ar- part 0f t]ie article into 16 chapters. In the firft of
tlcle' thefe we fhall treat of the charadteriftic marks, general
phenomena, duration, and principle of life. In the
fecond wre fhall confider the phenomena of ienfation, the
adtion of the nervous fyftem, and the external fenfes of
feeling, tailing, fmelling, hearing, and fight. In the
third and fourth chapters we fhall treat of irritability,
and the phenomena of motion. In the fifth we fhall
treat of digeflion ; in the fixth of abforption 5 in the
feventh of circulation ; in the eighth of reipiration and
voice } and in the ninth of nutrition, as completed by
the fucceflive performance of the four preceding func¬
tions. In the tenth chapter we fhall treat of the phe¬
nomena of fecretion j and in the eleventh, of thofe of Introduc-
excretion. In the twelfth we fhall confider the vari-, *;c;r"
ous means by which living beings defend themfelves " v
from external injury, or the phenomena that attend the
evolution and change of the integuments, to which func¬
tion we fhall give the name of inlegumation. In the
thirteenth chapter we fhall confider the transformations
that take place in feme tribes of living beings, efpecial-
ly infedls and reptiles. In the fourteenth we fhall
briefly examine the phenomena of reprodudlion, and
the hypothefes to which they have given birth. In the
fifteenth wre fhall confider the nature of deep, and die
phenomena of dreams) and in the fixteenth we fhall
terminate our inquiries by a few obfervations on the na¬
ture and phenomena of death.
The following table is intended to exhibit an outline
of the principal circumftances attending the phenomena
of life, in the order in which we have enumerated them.
id
Tabular
eutline.
I. Life—is either
” Univerfally diffufed through the body. Polypi, &c.
Moll concentrated in certain organs.
Continued for only a few hours. Ephemerce, andfame other infeEls.
. . —  about a year. Annual plants.
  two years. Biennialplants.
 feveral years. Perennial plants, and mojl animals.
 about a century. Elephants, pikes, &c.
   feveral centuries. Oaks, chefnuts, &c.
2. Sensibility—
Appears to
f Exifl in a very low degree in plants. Senjitivity.
j Exifts in a greater or lefs degree in all animals.
<{ Confined to the fenfes of feeling and tafle. Mojl %oophytes.
I Extended befides thefe to the fenfes of fmelling, fight, and hearing,
p Appears farther extended by an additional fenfe. Bats.
3. Irritability—
Affedled by
' Stimulants invifible.
—  unknown.
  unthought of.
The nervous influence.
Light.
- Heat.
Moifture.
Eledlricity.
Salts.
Gafes.
_ Bodies that a£I mechanically.
4. Motion—Per¬
formed by
r Legs.
Wings.
Fins.
< The tail.
Organs which fall not properly under thefe deferiptions, hats, flying opofjums, &c.
The fpringinefs of the body or of fome part of it, maggots, fleas, &c.
^ Contrivances which fit living bodies for being moved by foreign agents.
5. Digestion.
Introduc¬
tion,
5. Digestion—
Performed by an <
alimentary canal.
6. Absorption—
Performed by
PHYSIOLOGY.
' Without teeth.
With teeth in the mouth.
 in the ftomach.
- ■ ■ ftones or artificial teeth in the ftomach.
 glands in the mouth for fecreting a liquor to be mixed with the food,
 pouches in the mouth where the food is kept and moiftened.
 — a fac or bag where the food is kept and moiftened.
——- a membranous ftomach.
■ 1 a mufcular ftomach.
—  an intermediate ftomach.
Without a coecum or blind gut.
With a coecum. T
 two coeca. Thefe parts, as well as ruminating ftomachs and their oefophagus, have
 three coeca. ’ antiperiftaltic motions.
 four coeca. J
   one entrance or mouth.
 many entrances by abforbents.
Plants have many alimentary canals.
Some polypes have alimentary canals that branch through the body.
The alimentary canals of plants and worms diftribute the fluids without the aid of a cir¬
culating fyftem.
Veffels beginning from the alimentary canal.
      the cavities.
the furface.
<j the furfi
| Veins in the penis and placenta.
LRe -abforbents originating from all the parts of the fyftem.
7. Circulation—
Performed by a fy- <
ftem with
8. Respiration—
Performed by organs
One heart.
A heart for diftributing the blood through the refpiratory organs, and an artery for di-
ftributing it through the fyftem.
One heart for the refpiratory organs, and one for the fyftem, both in one capfule.
Two hearts for the refpiratory organs, and one for the fyftem.
A pulmonary heart, or a heart for the refpiratory organs in the courfe of circulation.
A pulmonary heart within or without the courfe of circulation at pleafure.
A heart fituated in the breaft.
   near to the head.
 — in the oppofite extremity.
__ Some animals and all plants have no circulating fyftem,
' Diffufed through the fyftem.
Confined to one place.
Situated externally.
 internally.
In the courfe of the circulation.
Not in the courfe of the circulation.
Within or without the courfe of circulation at pleafure.
Without tracheae.
With tracheae ramified through the fyftem where the refpiratory organs are generally
diffufed.
  not ramified through the fyftem where the refpiratory organs are confined. .
 formed by rings.
 by fegments of rings on one fide, and a membrane on the other.
by continuous rings running fpirally like a fcrew.
admitting air by one entrance.
by feveral entrances.
— wholly concealed in the body.
— partly projecting from the body.
 opening at the head.
 at the oppofite extremity.
, ,  upon one fide.
_— both Tides.
L 2
Nutrition.
A
452
Introduc¬
tion.
p. Nutrition—
Food prepared by
io. Secretion—
Performed by
ii. Excretion—
Excrementitious
matters thrown
out by
PHY
f The alimentary canal.
The la&eals.
The refpiratory organs.
< The circulating fyftem.
The cellular membrane.
The glands.
L And by the feveral parts
f Veffels.
| Exhaling veffels.
J Excretory organs,
j Organic pores,
j Glands.
I And by all the parts jo£ which the fyftem is compofed.
TThe integuments chiefly.
J The common openings of the alimentary canal.
J Two openings of this tube.
(_By the lungs and other emun&ories.
S I O L O G Y.
in which it becomes finally affunllated.
I2.INTEGUMATI0N—
Some living bodies
have integuments
which are
13. Transforma¬
tion—Takes place
' Scaly.
Shelly.
Membranous.
Corneous.
Cretaceous.
Ligneous.
Covered with down.
 hair.
 prickles.
—  feathers.
 a vifcid matter.
Change their colour.
 their covering.
_ Changed themfelves.
' By a change of proportion among the parts.
   of their form.
— throwing off old parts.
*  an addition of new ones of a different ufe, ftrutture, aftd form.
— a change of the whole form together.
 of qualities, propenfities, manners.
14. Generation—
Performed by
The temporary union of two fexes.
The fpontaneous reparation of parts.
Organs fituated in the breaft.
    in the fide.
  near to the head.
1 in the oppofite extremity.
An intrant organ of the male, and a recipient organ of the female.
An intrant organ of the female, and a recipient organ of the male.
The ftamina and piftils of flowers.
The feminal fecretion of the male thrown into the organs of the female.
   — fprinkled at the entrance of the female organs.
   thrown upon them from a diftance.
-   tranfported to them by the winds.
  fprinkled on the embryo after emiflion.
   diffolved in a fluid fecreted by the female before it can rightly per¬
form its office.
- - diffolved perhaps fometimes in air, as in the cafe of dioicous plants,
where it probably a£ts like an aroma.
15, Sleep—Natu¬
ral fleep is oc-
cafioned by
Quietnefs.
The abfence of ftimuli.
The famenefs of ftimuli when long continued.
Deficient affimilation.
Deficient irritability, which is owing fometimes to the weaknefs, inattention, or confined’
powers of the mental principle.
it Death. See Life,
The
PHYSIOLOGY.
4’5.
Hiftorjr.
27
Utility of
the hiftory
of phyflolo-
gy-
1%
Opinions of
Pythagoras
refpe&tng
59
©f Alcmse-
OfEmpedo-
cles and A-
naxagoras.
H I 3 T O K Y.
The early liiftory of phyfiology can be little more
than an account of the opinions of the ancient philofo-
phers refpefting the nature and functions of the human-
body j but as their opinions refleft confiderable light on
the progreflive improvemeftt of the philofophy of man,
the hiftory of phyftology, even in its early ftages, is cu¬
rious and interefting.
Of the origin of phyftology as a fcience we know no¬
thing. On examining the writings of the earlieft philofo-
phers, we meet with little more than a collection of ab-
ftraCt principles and hypothetical reafonings, efpecially
previous to Pythagoras. He confidered man as a mi-
crocofm, or an epitome of the univerfe, in which were
produced the fame phenomena as in the larger world,
only to a lefs extent. He admitted more than one
intelligent principle, conducing all the operations of
the human body. He fuppofed that the human foul
nouriftied by the blood, fixed by the veins, the arteries,
and the nerves, as fo many vifible fituations, became
obedient to the general laws of univerfal harmony. He
did not pretend that the eternal power of numbers had
prefcribed all the phenomena of nature, and that the
force of numerical harmonies regulated the motions of
the bodies which filled the univerfe, though he has been
made fo to exprefs himfelf by his difciples. He was
contented with aflerting, that every thing in nature was
brought about according to the qualities and proportions
of numbers, without attributing to them an intrinfic vir¬
tue and a pofidve exiftence. He perceived that the
phenomena of the animal economy fucceeded each other
with a ftriCh regularity, by which they concurred in
maintaining order j and in this order he found the prin¬
ciple of the exiftence and prefervation of all beings; a
principle without which they could not exift. He con¬
fidered the fouls of men as emanations from the general
foul of the univerfe, or anima munch.
Alcmaeon confidered the brain as the feat of the foul.
He fuppofed found to be produced by the reverberation
of the air within the cavity of the ear ; and he thought
that tafte was owing to the moifture of the tongue. He
compared the body of a foetus to a fponge, which obtain¬
ed its nourifhment by the fuftion eftabliftied over every
part of its fubftance. According to him, the motion of
the blood was the eftential principle of life ; and he fup¬
pofed that the ftagnation of this fluid in the veins pro¬
duced fleep, and its aftive expanfion brought back the
waking ftate of the body. Health confifted in the equi¬
librium and well proportioned mixture of certain pri¬
mary qualities; and that whenever any of thefe became
too predominant, difeafe was the confequence.
Empedocles involved himfelf in a multitude of ab-
furd hypothefes, in order to explain the formation of
man, and the combination of the elements from which
he was produced. He too, like the difciples of Pytha¬
goras, fought among the properties of numbers, for the
general principles both of phyfical and moral fcience.
In uniformity with this fyftem it was, that he reckoned
the four elements, and admitted among the particles of
thefe material principles a kind of aflfe£lion and aver-
fion, of defire and antipathy, capable of feparating and
reuniting them, as occafion might require. He be¬
lieved that relpiration commenced within the uterus,
where the infant was provided from each parent with
certain organic particles, which lendetf to unite Into one Hiftory.
uniform whole. Anaxagoras, convinced that we muft-v—
attribute the arrangement of matter to the intelligence
of a fuperintending being, imagined that the body of
every animal was formed of homogeneous particles,
which were brought together by a fort of affinity. It
appeared to him, that bodies which were endowed with
thought, were compofed of fenfible elements ; that thefe
elements remained unalterable, and that no power in
nature could exert any action on them. 31
Democritus dedicated his life to repeated experimentsDcmocrh'4S'
on plants and animals. He explained the principal phe¬
nomena of organized bodies by the adtion and reaction
of atoms, which he fuppofed to be endowed with powers
effentially aftive, and fufceptible of repelling and at¬
tracting each other. According to him, generation con¬
fifted in the cohefion of homogeneous atoms. He con ¬
ceived the heat inherent in the elements of the body to
be the foie aCtive principle with which man was anima¬
ted ; and that by increafe of this he became capable of
life and motion. He compared the organs of the fenfes
to mirrors, on which were painted the images of things,
and he reduced all fenfations to the fenfe of feeling,
which he fuppofed to be more or lefs delicate according
to circumftances. 32
Thefe philofophers, who lived before the time of Hi- Hippocra*
pocrates, had, as we fee, but very rude and indiftinCt no-tes*
tions of the animal economy \ nor were thofe of the
great father of phyfic much fuperior. Excellent as was
his praClice, and acute his knowledge of the fymptoms
and progrefs of difeafcs, the phyfiology of Hippocrates
was very lame and defeftive. He feems, indeed, to
have underftood the funCtion of nutrition better than
moft others \ he traces the aliment into the ftcmach,
feems aware of the procefies it has to undergo there, and
hazards a conjeCture that part of the chyle is taken up
immediately by the pores of the cellular texture ; and
that the juices admitted into this membrane, ferved for
the production of milk, the matter of which is after¬
wards tranfported, and laid up within the breafts. He
attributes to each vital part an attractive force, which
it exerts on the nutritious particles, in order to incorpo¬
rate and appropriate to itfelf thofe which bear to it a
certain analogy. He thought that the heat generated
in a living body was kept up entirely by the powers of
vitality; and that the external air introduced by refpi-
ration, ferved rather to check it, by exerting a cooling
effeCt on the pulmonary organs. He reprefents the hu¬
man body as agitated in all its parts by an alternate flux
and reflux, which carried the matters from within out¬
wards, or brought them from without inwards. From this
feme have fuppofed that he underftood the circulation of
the blood, a fuppofition made two hundred years ago,
and lately again brought forward by the French phyfio-
logifts. We fliall not at prbfent itay to canvafs this opi¬
nion, which, however, we conceive to be founded on
very unfatisfaCtory arguments. ,
After Flippocrates, the fcience of man was again left Plato,
to the fchools of philofophy, from which he had firft fe-
parated it. Plato is the firft philofopher whole opinions
merit particular notice. He wrote on the phyfiology
of man, with his accuftomed elegance and fplendor of
diClion •, and he aflumed the tone of an infpired prophet
in deferibing, with the force of enthufiafm, the grand
images that fuggefted thernfeives to his mind. Ac-
&ordui£.
PHYSIOLOGY.
cording to bim, tbs human body does not contain with¬
in itfelf the caufe of the phenomena which are the con-
fequence or the attendants of life. It is only a paflive
fubject, on which the foul expreiTes the feries of its func¬
tions, like the canvas on which the painter traces the
conceptions of his inventions. He diftinguifhes two
principles of aftion in man, a rational foul, on which de¬
pend refledtion and intelligence, and an irrational foul,
en which depend life and motion. The latter is dif*
fufed through every part of the body} and it is by
means of thefe parts that it feels, fuffers pain, or enjoys
pleafure. Thus it is by means of the heart it is fufcepti-
ble of courage and of paffion •, by the liver of defire. The
head is the feat of reafon 5 the cheft, and efpecially the
heart, the feat of ftrength and anger j the lungs, the
general coolers of the body. One divifion of the irra¬
tional foul, which pofleffes an appfetite for food, and all
the neceflary refrefhments of the body, refides in the
epigaftric region j which, in the language of Plato, is a
fort of liable,-in which refides a voracious animal. Du¬
ring nutrition, the vital parts afhmilate to their fubftance
the aliments which are prefented to them; and this affi-
milation is the confequence of an affinity that takes place
between thefe parts and the nutritious juices. He thus
feems to regard nutrition as the effeft of a combat be¬
tween the aliments and the parts of the animal. A
young animal will receive more nouriffiment than one
which is old, becaufe the force of its body has more
effedt in overcoming the force of the nutritious fub-
ftances.
As the reciprocal adlion of the foul and the body on
each other did not appear to him capable of being ex¬
plained on the luppofition of immateriality, he propofed
the idea of a plajlic nature, which he fuppofed to be
an intermediate principle connedting the foul and the
body.
The human body, which is entirely fpongy, is expo-
fed through every part to oppofite currents of air and
fire, which traverfe and penetrate it, being introduced
alternately by the lungs and by the fkin. Hot, cold,
denfe, rare, and the other fenfible properties of bodies,
are only the caufes of the phenomena which we per¬
ceive, and are, as it were, the occafions or accidents
that are required to keep in play the intelligent force
dilfeminated through nature.
Ariftotle, the difciple of Plato, for a long time dif-
puted with him the palm of genius and celebrity; but,
as his phyfiological dodtrines differed very little from
thofe of his mailer, it is unneceffary to detail them, ex¬
cept to remark, that he attributed to the foul three fa¬
culties, a nutritive, a fenjitive, and a rational faculty; in
the firft of which life is the only principle *, in the fe-
cond, feeling is produced ; and the third is peculiar to
man, and is that part of him which knows or judges.
This part is either an adtive or apaffive intelledl, of which
the firlt may be feparated from the body, and is immor¬
tal ; whereas the fecond perishes together with the body.
Life, according to this philofopher, is a permanence of
the foul, retained by the natural heat, the principle of
which refides in the heart.
About the period which we are now confidering, phi-
lofophy was divided into two fedls j the materialifts, who
attributed the formation of all beings to the fortuitous
concourfe of atoms ; and the fpiritualifts, who held that
the foul enjoyed an exiftence anterior to that of the bo¬
dy, which was no other than a paffive organ, in which Hiftoiy.
the phenomena that previoufly exifted in the foul, in an
abftradt, latent manner, became evident and fenfible.
To the former fedl belonged Democritus and Epicurus 3
to the latter, Zeno and Plato.
The profeffors of the Alexandrian fchool, though they Herophilus,
did much for the improvement of anatomy, added little
to phyfiology. Of thefe Herophilus brought to feme
degree of perfection the dodlrine of the pulie, and feems
to have underftood the adlion of the pulmonary organs
more corredtly than his predeceffors, attributing to them
a fort of natural appetite, by which they attracted and
rejeCled the matter of refpiration. He confidered the
nerves, the mufcles, and the arteries, as the moving
powers of the body. 35
In Galen, alio a difeiple of this fchool, we find the Galen,
molt fcientific phyfiologiit that has yet come under our
notice. He feems firlt to have afeertained by experi¬
ment, that the arteries contain blood, and not air, as
had been the opinion of Herophilus and his predecef¬
fors 3 and that they poffeffed a moving force, indepen¬
dent of that which the heart exercifes on the mafs of
blood, and he found that the contraction of the heart al¬
ways alternated with a proportional dilatation. He even
tried fome delicate experiments, in order to afeertain the
influence of the nervous fyffem upon the fenfitive and
motive powers of the body, by which he found, that
when a nerve was intercepted with a ligature, the part
to which it led became deprived of fenfe and motion.
He believed that the flomach, in a Hate of contrac¬
tion, applied itfelf to the aliment that had been taken
in ; that the mefenteric veins abforbed a portion of the
chyle prepared in the inteflines 3 that the duElus chole-
dochus carried the bile from the gall bladder into the
duodenum 3 that the kidneys feparated a part of the
urine 3 and he fuppofed, that another part of this fluid
paffed immediately from the ftomach to the bladder,
through fome unknown paffage. He believed that the
lungs tranfmitted to the blood contained within them,
an aerial principle, deftined to free them from fuliginous
vapours, and to temper the excefs of heat generated
within the body. The obfeure funCtion of generation
did not entirely efcape his refearches 3 and he made fome
curious attempts to find out how the fexual organs pre¬
pared the feminal fluid, and how this aCted in reproduc¬
tion.
For more refpeCting the doCtrines of Galen, fee the
Hiltory of Medicine. 3?
The commencement of the 13th century is the epoch The che-
of a material revolution in phyfiology. Chemiftry hav-nntts
ing penetrated into Europe, foon exerted its influence
on molt of the fciences, and efpecially on thofe connect¬
ed with medicine, the doCtrines of which were totally
changed from their ancient fimplicity, and became a far¬
rago of the moft wild and fanciful opinions. The Peri¬
patetics and the Galenifts funk into oblivion 3 and the pri¬
mitive qualities and occult faculties of the ancient fchool
gave way to the fermentations and effervefcences of the
chemifts. Albertus Magnus and Roger Bacon, when
they introduced the fcience of chemiftry, fcarcely dream¬
ed of applying it to medicine 3 but Arnoldus de Villa
Nova undertook this application, and fought for the
foundation of medical theory amid the proceffes of his
laboratory. Paracelfus followed, and furpaffed him in
this chemical delirium. An enlightened chemift and a
credulous
PHYSIOLOGY.
455
Hitfory.
38
Vaa Hel-
sacnt.
39
Bes Cartes.
40
Bifcovery
of the cir-
tulation.
credulous aftrologer, his head burning with the fire of
his furnaces, and his imagination filled with magical re¬
veries, he believed himfelf capable of conftrufting a new
fyftem of philofophy, from examining the courfe of the
ftars, and the produfts of his alembics. With the
daring affurance of infpiration, he declared man to be
compol'ed of fulphur, mercury, and fait ; and, having
traced the origin of all difeafes to certain chemical ope¬
rations, he flattered himfelf, that by means of his arca¬
na he could preferve health, and prolong, to an in¬
definite extent, the natural duration of human exift-
ence.
Van Helmont, the difciple of Paracelfus, not lefs fan¬
ciful, but more fcientific than his mailer, faw the necef-
fity of fomething more than chemical principles to ex¬
plain the functions of the animal machine. He there¬
fore introduced his archceus, an intelligent being, who
eflablifhed his throne in the epigaftric region, having le-
veral fubaltern miniffers under him, who prefided over
the feveral functions of the body, and whofe chief feats
were, the head, the chelf, and the belly.
In the philofophy of Des Cartes, the feparate exift-
ence of the vital principle is entirely rejedted. He avail¬
ed himfelf of the progrefs that had been made by Willis,
and fome other anatomiils, in the inveltigation of the
nervous fyftem, to form an hypothefis of the vital func¬
tions, founded on the fuppofition of the nervous fluid,
or what was then called the animalfpirits ; and this ner¬
vous fluid was affumed independently of the fenfitive
foul, to explain the appearances of fenfation and volun¬
tary motion.
The difcovery of the valves in the veins by Fabri-
cius ; of the lymphatics by Rudbeck and Bartholin j
of the ladleals by Afellius, and of the circulation of the
blood by Harvey, all of which took place during the
17th century, gave to phyfiology an intereft and a
clearnefs which it never poffefled before that period.
Some account of the difcoveries in the circulating and
abforbing fyftems, hath been already given under Ana¬
tomy 5 but as thefe difcoveries have been produftive of
great advantages, both in general phyfiology, and in
medicine, it will be worth while briefly to trace their
origin and progrefs.
To begin with the circulation of the blood. Hippo¬
crates fpeaks of the ufual and conftant motion of the
blood, of the veins and arteries as the fountains of hu¬
man nature, as the rivers that water the whole body,
and which if they be dried up, man dies. He fays, that
the blood-vefiels are, for this reafon, everywhere dif-
perfed through the whole body j that they give fpirits,
moifture, and motion j that they all fpring from one ;
and that this one has no beginning and no end, for
wdiere there is a circle there is no beginning. In fuch
language was the prince of phyficians accuftomed to ex-
prefs his vague ideas of a circulation j for fo far w7as he
from having acquired accurate conceptions on this fub-
jefr, that when he faw the motions of the heart, he be¬
lieved that the auricles were two bellows to draw in air,
and to ventilate the blood.
When after his time anatomy came to be more ftu-
died, the notions of the ancients refpefling the blood
were better defined j and, however chimerical they may
feem to us, they were partly derived from difleftion and
experiment. On opening dead bodies, they found that
the arteries were aimoft empty, and that very nearly the
whole of the blood was colie fled in the veins, and in Hiftory.
the right auricle and ventricle of the heart. They there- v
fore concluded that the right ventricle was a fort of la¬
boratory ; that it attrafted the blood from the cavae *,
by fome operation rendered it fit for the purpcfe of nu¬
trition, and then returned it by the way that it came.
From the aimed empty date of the arteries, they were
led to fuppofe that the right ventricle prepaied air, and
that this air was conveyed by the arteries to temper the
heat of the feveral parts to which the branches of the
veins wTere didributed.
To this lad notion, entertained by Erafiftratus, Ga¬
len added an important difeovery. By certain experi¬
ments, he proved, that the arteries contained blood as
well as the veins. But this difcovery was the occafion
of fome erubarraffment. How was the blood to get
from the right to the left ventricle ? To folve the diifi-
culty in which his new difcovery had involved him, he
fuppoled that the branches of the veins and arteries ana-
ftomofed j that when the blood was carried to the lungs
by the pulmonary vein, it was partly prevented by the
valves from returning •, that therefore during the con-
traflion of the thorax it paffed through the fmail inofeu-
latmg branches to the pulmonary vein’, and was tnei.ee
conveyed along with the air to the left ventricle to flow
in the aorta. This opinion, fo agreeable to laid, unfor¬
tunately afterwards gave place to another that was the
refult of mere fpeculation. This notion was, that the
left ventricle received air by the pulmonary vein j and
that all its blood was derived through pores in the fep-
tum of the heart.
The paflage through the feptum being once fuggefl¬
ed, and happening to be more eafily conceived than one
through the lungs, it wras generally fuppofed the only
one for a number of centuries j and fupported likewife,
as it was thought, by Galen’s authority, it was deemed
blafphemy in the fchools of medicine to talk of another.
In 1543, however, Vefalius having publilhed his immor¬
tal work upon the ftrufture of the human body, and gi¬
ven his reafons in the fixth book why he ventured to
diflent from Galen, he particularly fhewed how it was
impoflible that the blood could pafs through the feptum
of the heart. His reafoning roufed the attention of ana-
tomifts y and every one grew eager to diicover the real
paflage wdiich the blood muft take in going from the
right to the left ventricle. The difcovery of this w as
firll made by Michael Servede, a Spanilh phyfleian,
who publifhed his opinion in 1553. He expreisly lays,
that the blood does not pafs through the feptum of the
heart, as is commonly believed, but is conveyed by an
admirable contrivance from the right ventricle of the
heart, by a long paffage through the lungs. This opi¬
nion was deemed heretic, and Servede’s book was fup-
prefled by public authority. Soon after, however, the
fame difcovery was made by Realdus Columbus, an Ita¬
lian profeiTor, who publifhed his account in 1 5 yg. It
farther appears, that Andreas Caefalpinus, who pr'o’ifil¬
ed in 1^71, ard again in 159?, was acquainted, not
only with the lefler circulation, but obferved, that the
blood fometirre.s flowed from the branches of the veins
towards their trunks j and that when a vein was tied
with a ligature, it fwelled between the ligature and the
d'ftant extremity of the vein, and not between the liga-
tme and the heart. Fie thence inferred, that the veins
and arteries opened into each other, and ventured to af-
ferfe
PHYSIOLOGY.
Hiftirv.
fert that the blood could not return by the arteries to
the left ventricle of the heart. He did not, however,
dilcover the true circulation, but molt unaccountably
maintained with Ariitotle, of whom he was a zealous
•difciple, that the blood flowed like the tides of Euripus,
backward and forward in the fame channel, and fuppo-
fed that it flowed from the arteries into the veins during
fleep, and back again from the veins into the arteries
till the waking itate.
In 1574, Hieronymus Fabricius ab Aquapendente,
while he w’as feeking for a caufe by which to explain the va¬
rious fwellings of fome veins, which had arifen from friftion
and ligature, he, to his great joy and aftonifhment, dif-
covered their valves in one of his difle£tions •, and here
again the true theory of circulation teemed almoft una¬
voidable. Yet whoever reads the fmall treatife De Ve-
narum Oftiolis, firft printed by Fabricius in 1603, will
foon perceive that he was as far from entertaining a jult
notion of the circulation as his predeceflbrs. Notwith-
ftanding all that he faw, he ftill wras of opinion that the
blood flowed from the heart to the extremities even in
the veins. He thought that the valves wrere intended by
nature only to check and moderate its force. He calls
them an inftance of admirable w’ifdom, and miltakes his
own aukivard conjecture for one of the defigns of infi¬
nite intelligence. In another refpeCt, it muit be con-
fefled that he bore no inconfiderable lhare in promoting
the difcovery of the circulation. By writing on the
valves, the formation of the foetus, and chick in ovo, he
direfted the attention of his pupil Harvey to thofe fub-
jeCts wrhere it was likely that the motion of the blood
would frequently occur.
Harvey, who was bom in 1578, and graduated at
Padua in 1602, examined the valves with more accu¬
racy than Fabricius, and explained their ufe in a trea¬
tife which he publilhed foon after his graduation. In
1616, he taught the true doftrine of the circulation in
his leCtures, and publilhed on thefubjeCt in 1628. He
was the firlt author who fpoke confiftently of the motion
of the blood, and who, unbiafled by the doCtrine of the
ancients, drew rational conclufions from his experiments
and obfervations. His books prefent us with many in¬
dications of a great mind, acute difcernment, unwearied
application, original remark, bold inquiry, and a clear,
forcible, and manly reafoning •, and every one who con-
fiders the furprife which his doCtrine occafioned among
the anatomilts of thofe days, the ftrong oppofition that
it met with from fome, and the numerous and powerful
prejudices which it had to encounter from the fanCtion
of time and of great names, mutt allow it was new j and
that the author has from its importance, a title to rank
in the firft clafs of eminent difcoverers, ancient or mo¬
dern.
We have been the more particular in tracing the pro-
greflive difcovery of the circulation, and in attempting
to (hew that the real merit of the difcovery is due to
H a<vey, becaufe both the abilities and the originality
of this eminent man have been called in queftion by his
countryman Dr William Hunter •, and many hints are
given in the writings of fome foreign phyfiologifts, that
the circulation wras at leaft gueffed at by Hippocrates and
other ancient writers.
We (hall be lefs minute in tracing the difcovery of the
lymphatic fyflem, becaufe this has been related more at
-large in the article Anatomy.
4
We learn from Galen, that certain veiTels had been tftitoiy.
feen in kids by Eraliftratus, which appear to have been ' v~—
lacleals, though he called them arteries. Thefe laCleals 41
were, howrever, firft accurately diftinguithed in 1622,^^'^
by Afellius, who printed his account in 1627. Inforbentfv.
1651, Pecquet publilhed his account of the thoracic ftem.
dud:, which appears, however, to have been feen be¬
fore by Euftachius. In 1653, Bartholin publiihed on
the lymphatics, w’hich had been fome time before dif-
covered by Rudbeck. In 1654, Gliffon afcribed to
thefe vefiels the office of carrying back the lubricating
lymph from the arteries into the blood, or confidertd
them as abforbents. In 1664, the valves of thefe vef-
fels were difcovered by Swammerdam, and a year after,
an account of them was given by Ruyfch. The farther
difcoveries of Nuck, Nouges, Warton, Steno, Hunter,
Monro, Hewfon, Cruiklhank, Sheldon, Mafcagni, &.c.
have nearly completed our knowledge of the abforbent
fyftem, and its ufes.
In the latter end of the 17th century, fome ijnportant
difcoveries w7ere made on the fubjed of refpiration, by
our countryman Mayow j and thefe were fupported by
the obfervations of Lower, Verheyen, and Borelli.
Thefe difcoveries, however, lay dormant till they wrere
brought into recolledion a hundred years after in con-
fequence of the experiments of Prieflley and Lavoilier.
During the 17th century, confiderable progrefs was
made in completing the knowledge of the internal or¬
gans of generation. Much was done in this way by De
Graaff and Malpighi, and Leuwenhoeck, the two latter
of whom made feveral difcoveries with the affiftance of
their microfcopes, though Leuwenhoeck founded on his
obfervations a theory of generation which at this day ap¬
pears not a little ridiculous.
The beginning of the 18th century is remarkable forSyftem of
the promulgation of a new pbyfiological dodrine, found- Boerhaave.
ed on a miftaken application of the circulation of the
blood. We allude to the fyftem of Boerhaave. This
great phyfician fuppofed that all the fundions of the liv¬
ing body, excepting the will, are carried on by mecha¬
nical movements, fufceptible of rigid calculation, which
neceflarily fucceed each other in the organs, from the
time that life commences. Thefe movements are brought
into adion as foon as the animal begins to refpire, and
are the confequence of an impuliive power in the heart,
renewed by means of the influence of the nervous fluid
brought from the brain. He conceived the living body
to be merely a hydraulic machine, in which the heart
performs the office of a pifton, and that the alternate
contradions and dilatations that take place without
intermiflion in that organ, are owing to the alter¬
nately increafed and diminilhed compreffion of the
nerves that are diftributed to the heart. When a con-
tradion takes place, the blood fills the large arteries,
and thus diftends and compreffes them ; when the prin¬
cipal nerves of the heart, which pafs between thefe ar¬
teries, muft of courfe become compreffed, and thus their
influence being diminifhed, a relaxation takes place.
But in proportion as the heart is relaxed, the large ar¬
teries become empty, and confequently ceafe to com-
prefs the nerves, which thus recovering their influence,
reanimate the heart to a new contradion. Thus fuc¬
ceed each other without interruption the movements
which form the mechanical principle of all the fenfible
motions that we obferve in the animal machine.
Proceeding
P H Y S I O L O G Y.
457
Proceeding on tliefe principles, Boerhaave conceived
fome very Itrange notions refpeding the coniiituent
properties oi the living fluids, in which he faw no other
mark of vitality than the globular form of their particles.
He confined all the fun&ions of the feveral organs to
the operation of rounding into fpheres the particles of
the fluids which were prefented to them, or of preferv-
ing that form in thofe which they already contained.
He thought that the lungs were chiefly of advantage,
■becaufe they contained within them a complete feries of
veffels, in which the particles of the blood can receive
all thofe dimenfions which may fit them to circulate
. through the reft of the body. The greater or lefs ve¬
locity with which the fluids circulate through the fecre-
tory organs, conftitutes the principal diflerence in the
nature of the fecretions. Various orders of veffels re¬
ceive the blood and other fluids which pals through
thefe divifions, fubjedf to the laws of hydraulics; and
when a fluid got by chance into an order of veffels that
was not fitted to receive it, fome difeafe was the confe-
quence. Every thing in the animal machine was redu¬
ced to an affemblage of conduits, canals, cords, levers,
pulleys, and other mechanical contrivances, put into ac¬
tion by mechanical means.
Thus was completed the fyftem of mechanical phyfio-
logy, which was begun fome time before by Bellini
and Borelli j and this fyftem maintained its ground in
defiance of obfervation and common fenfe, till about
the middle of the xBth century. In the mean time,
however, there arofe two men, whofe enlarged ideas
and acute genius induced them to diffent from the re¬
ceived opinions of the day, and to think for themfelves.
Thefe were Hoffman and Stahl, who, though they
did not, any more than Boerhaave, form complete or un-
objeflionable theories, contributed much to improve our
ideas of the animal economy.
Hoffman faw, that in the living body we ought not
to feparate the principle of vitality from the general
properties of matter. He believed that that principle,
fufceptible in itfelf of aftivity and motion, wTas fufficient
for all the occafions and all the functions of the body
which it animated. The animal body xvas not, in his
eyes, an hydraulical elaftic machine, formed of folids
and canals, differing only ifi fize, form, elafticity and
force. He faw, that if the fblids a£t upon the fluids,
thefe mitft, in their turn, reaft upon the folids ; and
that life could fubfift only by thefe mutual aftions and
•reaftions. The effential caufe of life, according to
Hoffman, is the progreflive motion of the blood, occa-
fioned by the impulfe of the heart, and kept up by the
alternate contraclions and dilatations of the veffels.
Thefe contrablions and dilatations are the confequence
of the force of an elaftierty inherent in the vafcular
fibres, and this force is ftill farther promoted by the
different ftruclure of thefe elaftic fibres, which is fuch
that they can be penetrated by the blood and the ner¬
vous fin'd. This laft fluid he imagined to be compofed
of aerial and etherial particles enveloped in a certain
portion of a very pure fubtile lymph, that ferved them
as a vehicle. By this fluid the cavities of the nerves
are filled, and it conftitutes the fenfitive foul, in which
refides the feat of the paffions. Now', all the functions,
even thofe which we attribute to a fentient principle, are
the efleft of phyfical powers, whofe mechanifm has,
however, fomething more fubikne and more exalted
VOL. XVI. Part II.
with rcfpeiT to the animal operations than to others. Huiovy.
If all the nervous, vafcular, and membranous parts, ~V“—-
preferve a moderate degree of adftion, and a moderate
ftate of tenfion and relaxation, the folids are fubje&ed
to ofcillatory motions which balance each other, and
produce a proper equilibrium in the fyftem. In this
ftate, all the operations of the body and the mind take
place with proper regularity 5 and this happy harmony,
by affuring to the animal the entire plenitude of its ex-
iftence, becomes the foundation of health. This degree
of moderate tenfion is always more or lefs altered in a
ftate of difeafe.
Little fatisfied with all the theories founded on a grofs of Stahl,
mechanifm, and convinced of their infufficiency to ex¬
plain the phenomena of vitality, Stahl admitted forces
that were fomething more than mechanical, and that
were direfted by an intelligent principle which applies
them to their deftined ules, and which, by diftributing
them with a wife economy, proportions or accommo¬
dates them to the different occafions of the individual.
His difciples confider Stahl as the firft modern writer
who has treated the fcience of man on a general plan,
and according to a philofophical arrangement 5 and as
his dobtrine has ftill numerous advocates in the medical
Ichools of France, we ftrall be fomewhat more particu¬
lar on it than on that of Hoffman.
In determining the limits between medicine and the
other phyfical fciences, Stahl commences with leparat-
ing from the former all thofe principles which, though
true in themfelves, have no relation to the nature of that
fciencc, which he confiders as originating in obfervation
alone. The knowledge of the pbyfical ftate of the ani¬
mal body cannot, he thinks, throw any light, either on
the injuries to which it is expofed, or on the means of
preventing or removing them. Confequently it is of
little ufe in medicine, and has no right to govern an art,
the objeft of which is, to remedy thefe injuries- that
threaten the human body. He proves that living bodies
are freed from the neceffary laws of mechanics, becaufe
all their aftions tend to one common end y—an end which
embraces the whole chain of the movements effential to
life, and the means eftablifhed for its prefervation. The
human body, by means of this mixture of mechanical
and vital powers, tends naturally to felf-deftruftion j but,
on the other hand, the organic ftrufture to which is at¬
tached the exercife of the aftions peculiar to the human
fpecies, is founded on this mixture. It is therefore ne¬
ceffary that the body (hould be in a ftate of refilling this
tendency, in order that it may be luftained ; and as the
corruptibility inherent in its nature, purfues it through
every period of its exiftence, the oppofing aclion necef¬
fary to prevent the corruption from taking place, mu ft
alfo be exercifcd without intermiflion. It is this pre-
ferving action that conftitutes the effence of life.
The prefervation of the body is indeed effeiled by a
fort of mechanical aflion ; it requires the corporeal or¬
gans as its inftruments, and it depends on different co-
exifteut and fuccefflve aftions. Health is the refult of
that juft conformation of the organs which enables them
to perform their fun6lions with eafe.
The exafl conformity which fubfifts between the
ftrufture of each organ, and the funflions it is deftined
to perform, demonftrates to the philofophical eye an in¬
telligent and wife principle, that in the formation of
organized bodies dirccls and preferibes every thing in
3 M the
45S PHYSIOLOGY.
Hifbry. tLe manner moft favourable to ibe end which it pro-
-v—J p0fes. fpeculative metaphyfician, accuftomed to
wander over the field of abllraftion, to enlarge the
fphere of his intellecbjal notions, to transform ienlible
objects into ideas, this author could never perihade him-
felf that a being could not proportion and adapt its or¬
gans to the operations they are to perform, without pof-
letling a knowledge of thefe operations, and having al¬
ready exercifed a judgment with refpeifl to them. Xt is
from this that he confounds the principle of liie with the
thinking foul, which being inceifantly prefent in every
part of the body, direfts and difpofes them according to
its own views, and to the end that it propofes in the con¬
tinual developement of the actions it is to conduct'.
The formation, the itrufture, duration and move¬
ments of the body, do not belong peculiarly to it, as it
is only a pafiive fubject on which the foul imprelfes and
realifes the idea of the phenomena that lire has con¬
ceived. Every thing is derived from the union of the
body with the active forefeeing principle, which governs,
according to fpecial laws, thole phenomena which are
more particularly vital, and which are molt indepen¬
dent of the will. The immediate action of this latter
faculty does not require the afliltance of any other fub-
Itance. The intervention of an intermediate principle
would be there fupertluous j and Stahl rejects that of the
animal fpirits, which had been introduced to explain the
jmechanifm of vitality, and which, by overcharging the
fcience, embarralfes it with a ufelefs hypothelis.
Two faculties are fufficient for the foul to act upon
the body, and to preferve it in a living date, viz. thofe
of fenfe and motion. By the former the animal learns
to know the properties of the objects by which he is fur-
rounded, or in which he is interelled, and to eltimate
the relations that fublilt between thefe objects and him-
felf; the latter produces the motion of the whole ma¬
chine, and determines all the changes of lituation which
it has to undergo in its whole, and in its parts.
The faculty of fenfation has two modifications, rela¬
tive to the two kinds of knowledge which the foul may
receive by means of that function. The firfl of thefe
relides in the organs of fenfe, and is adapted to external
objects ; the fecond eitablilhes its feat in the interior or¬
gans, and refers to objefts that are within, or ideas.
Sometimes the moving powTer enveloped in the mufcular
fyltem is difplayed by the fenfible aftions that regulate
the pofition of the body with refpect to the objects of the
univerfe, of which it makes a part ; fometimes concen¬
trated vyithin thefe organs, it excites inteftinal motions,
which maintain among their conftituent parts, thofe re¬
lations, and that equilibrium, which are neceffary to pre¬
ferve the healthy date, confidence, and tone of each or¬
gan. The mufcular apparatus is fubfervient to the ex-
ercife of the fenfes •, and the different motions which it
imprefles on the body, for the purpofe of tranfporting it
towards, or to a didance from, certain objects, are al¬
ways determined by the convenience or inconvenience
which the body, by means of the fenfes, experiences
from thofe objedls. The tonic motion, determined by
the confufed ideas of the principle of life, is difplayed
in the mod hidden organic parts, in the mod perfedf re-
pofe and profound filence of the voluntary movements.
The foul gives to its organs the difpofition that is fa¬
vourable to the fenfations it widres to receive, by virtue
©f the judgement that it exerts refpe&ing thefe fenfations,
before it has experienced them. This judgement is ex- Hirtcry.
erted on the relations betvreen the objects that excite' 1 v~“ ■"
thefe imprcdions, and the adtual date of the body 5 and
it is the intuitive knowledge of thefe relations that deter¬
mines, in all their infinitely diverfified diades, the plea-
lure or the pain which the animal experiences from the
objects that iurround it.
Stahl regards the excretions as the means employed
by nature to counteract the natural tendency of the body
towards putrefaction. He believes that the animal hu¬
mours are exceedingly difpofed to thicken, and that the
circulation of the blood is the means made ule by nature
to keep up their original tluidity. One of the caufes
that mod favour the tendency ot the humours to putre¬
faction, is plethora, to w hich nature oppcles, fometimes
the motion ofthe folids that didribute the blood; fometimes
the hemorrhagic fluxes which unload the vafcular fydem.
Thefe latter opinions are the principal foundations of
what has been called the humoral pathology, which pre¬
vailed fo long in mod of our medical Ichools, and w hich,
w ith certain modifications is did maintained in many parts
of the continent. ^
The favourable impulfe given to phyfical fcience in Of Haller,
general, by the philofophical writings of Bacon and
New ton, extended itfelf at length to phyfiology ; and
phydological writers became convinced that it was bet¬
ter to colleCl and arrange the faCts that related to the
economy of living beings, than to frame hypothetical fy-
dems concerning them. The honour of forming a ra¬
tional diged of the phenomena of the animal economy
was .referved for Haller, who perceived the importance
of affembling under one view, the experiments, faCts, and
oblervations of preceding writers, and of fubdituting
them in the place of hypothetical reafonings. He traced
the plan of the immenfe edifice that he defigned to con-
druCt in his Flr/t Lines of Physiology, and executed it on
a grand and extenlive fcale, in. his Elements, in which he
has brought together into a body of doCtrine, as complete
as could be expeCted in his time, all the materials of the
fcience. He perceived the inconvenience of a too driCt
application of the laws of mechanical philofophy to the
living fydem. He admitted an aCtive force, which he
confidered as peculiar to the animal body, viz. irritabili¬
ty, which contains the reafon or the experimental caufe of
mufcular motion. He maintained that irritability Ihouid
never be confounded with fenfibilily, and that the irritable
fibre differs as much from the fenfible fibre, as thefmudion
of motion from that of ienfation. Ladly, in his Opera Mi¬
nora, he lays down many new and important points of doc¬
trine refpebfing the ftrufture of our organs, and the mecha-
niim of our functions j and he relates a number of expe¬
riments made on living animals, for the purpofe of draw¬
ing from nature the fecret of thofe phenomena which die
appears mod defirous to conceal. We owe to Haller
fome curious relearches refpe6ting the formation of bone,
and the production of callus, as well as lome important
elucidations of the manner in which the embryo con¬
tained in the egg is developed, and paffes through the
fuccedive dages of its organization. He has led us
many experiments and details relpefting the drufture of
the heart, the circulation of the blood, and the puliation
of the arteries ; on the mecbanifm of the ribs, and the
aClion of the intercodal mufcles during refpiration ; on
the differences between the fenfible and irritable organs j
on the aClion of the brain and nerves, &c.
Th$
P H Y S I
Hiftory. Tlie latter half of the 18th century is remarkable for
' many able phyhologifts, who will be admired by pofte-
rity, either for the acutenefs of their genius, or the im¬
portant improvements that they have made in the fcience.
We may mention the names of Bordeu, La Caze, Bon¬
net, Vicq d’Azyr, Bichat, Dumas, and Cuvier in
France j of Fontana and Spallanzani in Italy, and of
Whytt, Cullen, Brown, and Darwin in Britain. We
cannot pretend to enumerate all the opinions and difco-
veries of thefe celebrated men, but muft content our-
felves with giving a flcetch of the three rival fyltems of
Cullen, Brown, and Darwin, and a brief outline of the
^ opinions of Bichat.
Of Cullen. The phyfiological fyftem of Cullen was founded chiefly
on that of Hoffman. He placed the principle of the
whole animal economy in the movement of the vital
folids, regulated by the fundamental law's of the ner¬
vous fyftem. This notion of the vital folids, according
to him, originates in the nerves, and being almoft alwrays
united in the fenforium, is eafily tranfmitted from one
nervous part to another, as long as the medullary fub-
ftance of the nerves continues in its natural ftate of life
and continuity. The contraction of the moving fibres
connected with the fenfible organs through the medium
of the brain, is the direCt effeCt of a movement that
commences with thofe objeCts. It is on the contractility
inherent in the moving fibres, excited by their own ex-
tenfion, by the application of various ftimuli, and often
by the immediate influence of the animal or nervous
powers, that all the phyfical aCtions of a living being
depend. He regards this contraCtile force as diftimft
from all thofe which are poffeffed by the Ample folid,
and the inorganic elaftic parts of the body.
Of the theory of Brown, rve have given a fufficient
detail under his life, and need not repeat it here.
Of Darwin. It is not eafy to give a compendious view of the fy¬
ftem of Dr Darwin, that {hall be intelligible to thoie
who have not examined his celebrated work, the Zoo-
nomia ; but we (hall endeavour to give as brief and per-
fpicuous an account of it as poflible. It is neceffary firft
to notice the deferiptions given of the terms to be em¬
ployed, which are as follows.
The immediate organs of fenfe are, by Dr Darwin,
aflerted to confirt, like the mufcles, of moving fibres.
The contractions of the mufcles and of the organs of
lenfe, are comprehended under what are called fibrous
motions, in contradiftinCHon to the fenforial motions, or
the changes which occafionally take place in the fenfo¬
rium. By this latter term is underftood, not only the
medulla of the brain and nerves, but alfo at the fame
time that living principle or fpirit of animation, which
relides throughout the body, and which wTe perceive
only in its effeCts. An idea is defined to be a motion
of the fibres of fome immediate organ of fenfe; and
hence is frequently termed alfo a fenfual motion. Per¬
ception comprehends both the fibrous motion or idea,
and the attention to it. When the pain or pleafure arif-
ing from this motion and this attention produces other
fibrous motion, it is termed fenfation ; thus limiting this
term to an aClive fenfe. Ideas, not immediately excited
by external objeCls, but v'hich recur without them, are
termed either, i. Ideas of recolleciion, as when w'e will
to repeat the alphabet backwards ; or 2. Ideas offuggef-
iton, as when we repeat it forw'ards, A fuggefting B B
fuggefting C, &c. from habit.
O L O G Y.
After mentioning a number of experiments to prove
the fibrous motions of the organs of fenfe, LA Darwin
proceeds to lay down the following lawrs of animal cau-
faticn.
1. The fibres which conftitute the mufcles, and or¬
gans of fenfe, poflefs a power of contraction. The cir-
cumftances attending the exertion of this pow'er of contrac¬
tion conftitute the laws of animal motion, as the circum-
ftances attending the exertion of the power of attraction
conftitute the law's of inanimate matter.
2. The fpirit of animation is the immediate caufc of
the contraction of animal fibres. It refides in the brain
and nerves, and is liable to general or partial diminution
Or accumulation.
3. The ftimulus of bodies external to the moving or¬
gan is the remote caufe of the original contractions of
animal fibres.
4. A certain quantity of ftimulus produces irritation,
which is an exertion of the fpirit of animation exciting
the fibres to contraction.
5. A certain quantity of contraction of animal fibres,
if it be perceived at all, produces pleafure ; a greater or
lefs quantity of contraction, if it be perceived at all, pro¬
duces pain. Thefe conftitute fenfation.
6. A certain quantity of fenfation produces defire or
averfion. Thefe conftitute ‘volition.
7. All animal motions which have occurred at the
fame time or in immediate fucceffion, become fo connect¬
ed, that when one of them is reproduced, others have a
tendency to accompany or fucceed it. When fibrous
contractions fucceed or accompany other fibrous contrac¬
tions, the connection is termed ajjfociation ; when fibrous
contractions fucceed fenforial motions, the connection is
termed caufation ; when fibrous and fenforial motions re¬
ciprocally introduce each other, it is termed catenation
of animal motions. All thefe connections are faid to be
produced by habit ; that is, by frequent repetition.
Thefe law's of animal caufation are, according to our
author, evinced by numerous faCts, which occur in our
daily exertions, and are employed by him to explain the
difeafes and decay of the animal fyftem.
I he fom fenforial powers, upon which all the aCtions
or motions depend, are thus characterized :
Irritation is an exertion or change of fome extreme
part of the fenforium, prefiding in the mufcles or organs
of fenfe, in confequence of the appulfes of external
bodies.
Senfation, is an exertion or change of the central parts
of the fenforium, or the whole of it, beginning in fome of
thofe extreme parts of it, which refide in the mufcles or
organs of fenfe.
Volition is an exertion or change of the central parts
of the fenforium, or of the whole of it, terminating in
fome of thofe extreme parts of it which refide in the muf¬
cles or organs of fenfe.
Ajfociation is an exertion or change of fome extreme
part ol the fcnforium, refiding in the mufcles or organs
of fenfe, in confequence of fome antecedent or attendant
fibrous contraClions.
To theie four faculties correfpond fo many claffes of
fibrous contractions, named irritative, fenfitive, voluntas
ry, and officiate. But all mufcular motions, and all
ideas,, are originally irritative, and become caulable by
fcnfation and volition from habit, i. e. becaufe pleafure
ox pain, or defire or averfion, have accompanied them ;
3 M 2 thofe
459
Hiftory.
PHYSIOLOGY.
460
Hiftory. tliofe ideas or mufcular motions wliich have been fre-
quently excited together, ever afterwards have a tenden¬
cy to accompany each other.
Of thefe motions the ajjbciate feem mod to have ex¬
cited Dr Darwin’s attention. He divides them into
three kinds; irritative ajjbciations, as when any part of
the extracted heart of a frog is irritated by pundure,
the whole heart contrails regularly ; fenfitive ajjbcia¬
tions, or the trains or tribes of motions eftablilhed by
pain or pleafure j and voluntary ajfociations, or thofe pro¬
duced by volition.
The aifivity of this power of volition is fuppofed to
form the great difference between man and the brute
creation ; the means of producing pleafure and avoiding
pain given to man by this power being denied to
brutes.
Correfponding to thefe four clalfes of motions, there
are four claffes of ideas ; irritative, preceded by irrita¬
tion ; fenfitive, preceded by the fenfation of pleafure
or pain ; voluntary, preceded by voluntary exertion ;
and djfociate, preceded by other ideas or mufcular mo¬
tions.
It has been obferved in Hudibras that
“   A rhetorician’s rules
Serve nothing but to name his tools.”
So we find that a ccnfiderable part of Darwin’s work is
taken up in eftablifhing the new meaning which he at¬
taches to terms well underflood and long adopted.
We cannot enter more fully at prefent into the opi¬
nions of the Zoonomia, but we fhall have occafion to
notice feme of them in the fucceeding part of this ar¬
ticle.
Opinions Bichat’s fyflem, which has made fo much noife on the
and ar- continent, is chiefly founded on the divifion of life into
rangement pwo kinds, organic and animal; the former of which is
of Bichat. comraon t(j aii organized beings, while the latter, as its
name imports, is peculiar to animals. Each of thele
two kinds of life may be confidered as compofed of two
orders of fumSlions, which fucceed each other in an
inverfe order. The firfl of thefe feries in animal life
commences with external objects, and proceeds towards
the brain j the fecond begins in the brain, and is thence
propagated to the organs of motion and voice. In the Hitldry.
firil order of functions, the animal is paffive ; in the le- ^ "Y
cond he is active. External objedls act on the body
through the medium of the firfi ; by the fecond, the body
reahls on external objects.
Two kinds of motion take place in organic life. In
the firll the formation of the body is conftantly going
on ; in the fecond there is a conflant decompofition :
hence the elements of the body are continually chang¬
ing, while the organization continues the lame. Orga¬
nic life is accommodaied to the continual circulation of
matter. The one order of functions affimilates to the
nature of the animal, the nutritious particles received
into the fyltem ; the other rejects what is ufeiefs, or is
fo much altered as to become noxious. The affimilat-
ing order of functions confifts of digeflion, circulation,
refpiration, and nutrition ; all of which proceffes the
matter received into the body mult undergo, before it
can become a part of the animal lubflance. When it
has for fome time conflituted a part of the body, it is
taken up by abforplion, conveyed into the circulation,
and thrown out thence, by cutaneous or pulmonary-ex¬
halation, or by fome other emunftories. Hence, the
fecond order of organic functions, or difaflimilating
functions, confift of abforption, circulation, exhalation, <
fecretion, and excretion. The brain is the centre of
animal life ; the heart of organic Ife.
Bichat confiders the proper balance of life to be pre-
ferved by the proportion which exifts between the ac--
tion of furrounding bodies, and the reaction of the fy-
ftem. This reaftlon is greateft in youth, hence the
principle of life is at that time in excels. It is lead; in
old age, and then the vital principle is defective. The
meafure of life is therefore the difference which exifts
between the efforts of external powers to overturn life,
and the internal refiitance to fupport it. I he excels or
the former fhows the weakneis of life ; that of the latter
indicates its flrength.
The following table exhibits Bichat’s diftribution of
be organs, or, as be calls them, appareils, belonging to
animal and organic life, and to generation, which is
common to both.
I. Organs of Animal Life.
r . 1 . . C 1. The bones and their dependanccs.
v i. Locomotive, including ^ 'j'^e mufcles and their dependances.
2. Vocal, including the larynx and its dependances.
t/5
'A
<
o
O
3. External Jenji-1 jnclu(i;ng
live, \
4'„t<W/''”/’}includ’ing
f 1. The eye.
) 2. The ear.
3. The noftrils.
| 4. The tongue.
5. The fkin and its dependances.
f 1. The brain and its membranes,
i 2. The fpinal marrow and its membranes.
5. ConduBing fen- T . f ^ rp^e cerebral nerves.
fation and mo- >- including -< ^ 4^ nerves Qf t}le ganglia.
t J l-
Organs
Hiftorr.
PHYSIOLOGY.
II. Organs of Organic Life.
4-6 i
Hiftory;
r
i. Dige/tive,
2. Refpiratonj,
3. Circulatory,
4. Abforbent,
J
5. Secretory,
'a
<
C
o
"J f 1. The mouth.
2. The pharynx and cefophagus.
1 . . a. The itomach.
] mcludmg j ^ The fmall inieftines.
J 5. The large inteftine#.
[_ 6. The peritoncemn and epiploon.
^ including
■ including
including:
including;
^ 1. The trachea.
£ 2. The lungs and their membranes.
1. The heart and its membranes.
2. The arteries.
3. The veins of the general fyftem.
4. The veins of the abdominal fyftem.
1. The abforbent glands.
2. The abforbent vefiels.
1. The lachrymal dufts.
2. The falivary and pancreatic du£ls.
3. The biliary and fplenic dufls.
4. The urinary paffages.
III. Organs of Generation.
^ [ 1. Male.
5 \ 2. Female.
^ 3 - Produced by this
O [_ union,
including
C 1. The membranes and placenta.
2. The foetus.
Recapitula- We ’iave now ta’Ken fuch a view of the progreflive
tjon. 1 ftate of phyfiological fcience, as we deemed confiftent
with the nature and extent of this article. It has
taught us that the prevailing fpirit of every age has had
a marked influence on the produftions both of art and
fcience that have appeared during that period ; and that
phyfiology has always been impreffed with the charac¬
ter of the fcience that was moft prevalent at any parti¬
cular period. While the doftrines of Ariftotle pre¬
vailed in the fchools, phyfiology never extended beyond
the bounds that had been let to it by Galen 5 and the
belief in occult qualities univerfally prevailed. When a
tafte for metaphyfical fpeculations began to gain ground,
this fcience w^as given over to the moft abftraft lubtili-
ties and abfurd fictions. When Des Cartes had re¬
formed the principles of the ancient philofophy, the
ftudy of the animal economy, like all the other branches
of phyfics, was fettered by the trammels of the Carte-
fian doftrines. After the genius of philofophers was
directed to chemiftry, phyfiology alfo took a chemical
turn, which it quitted only to take a new dire&ion point¬
ed out to it by the tafte for mathematics and mechanical
philofophy, which prevailed among all the literary at
the end of the 17th and beginning of the 18th century ;
and now that the ftudy of chemiftry is become fo gene¬
ral, wre fee that phyfiologifts are for reducing the func¬
tions of the animal economy to the analytical and fyn-
thetical operations of the laboratory, and converting the
living body into a furnace where a conftant combuftion
is going on while life remains.
We are now to enter on the phenomena of life, and
the functions of organized beings j and here we muft
premife, that in our illuftration of thefe phenomena and
funftions we ftiall occafionally refer to every clafs of
living creatures; it being our obje£t rather to give a
comparative view of phyfiology in general, than to con¬
fine our remarks to the human economy in particular.
Indeed much of the phyfiology of man has already been
given under Anatomy and Medicine j and of that of
the inferior animals, we have treated of the phyfioiogy
of the order Cete under Cetology •, of that of Reptiles
under Erpetology •, of that of Fijhes under Ichthyo¬
logy j of that of Serpents under Ophiology.
Chap. I. Of the General Phenomena of Life.
51
When wTe take a general view of the objefts or na-General
ture, we fee that they differ from each other in many of Life,
important particulars, and we foon find that they may
be conveniently divided into two great claffes j one
capable of growth, nourifhment, and reprodudlion j tne
other not fufceptible of thefe changes. We perceive
that all thofe fubftances which are found in the bowels
of the earth, and many of thofe which appear upon its
furface, continue for an indefinite time in the fame cir-
cumftances, until they are atted on by each other, when
they undergo certain changes which entirely alter their
nature and former properties.
Sulphur, in its natural ftate, is a folid fubftance info-
luble in water, and poffefling little a&ivity when ap¬
plied to the human fkin ; but if it be fubje&ed to the
action of heat, in contaft with atmofpheric air, or any
other gas containing oxygen, it becomes a fluid, very
mifcible with water, and of a moft corrofive quality,
namely fulphuric acid. The hydrogenous gas found in
the upper part of mines, would remain for ever uncom¬
bined with the oxygenous gas which forms part of the
atmofphere in which it floats, were it not fubje&ed to
the a&ion of caloric, or ele&ricity in a very concentrat-
462 P H Y S I 0 L O
General ed dale j but as foon as either of thefe agents comes in
ofLifeena conta(^ ^ie mechanical mixture of gafes, a com-
G Y.
52 .
Diftindtion
between
organized
and inor¬
ganic mat¬
ter.
bination takes place, attended with a tremendous ex-
plolion, and the hydrogenous gas difappears.
We find that all the bodies to which we give the
name of minerals, poffefs no power in themfelves which
can enable them to refill the operation of external a-
gents ; each individual of them is compofed of a fmall
number of principles, and their texture appears to be
made up of independent particles. Every other body
in nature, comprehending the almolt infinite variety of
plants and animals, though under certain circumlfances
fubjeft to the fame changes wdiich take place among
minerals, have, when thefe circumltances do not exill,
an innate property by which they are enabled to refill
the produftion of thefe changes. They do indeed
undergo certain alterations, but by thefe their original
habit and elfential properties are not changed. From
the time that a plant fprings from the feed, till it ceafes
to vegetate, it is perpetually receiving an acceflion of
new matter, and giving out a part of its former compo-
lition : but the new matter is allimilated to it, and be¬
comes a part of the plant; the identity of the plant is
preferved, though its component parts are perpetually
changing. The lame in a Hill higher degree takes place
in animals. The individuals of this latter clafs, com¬
prehending plants and animals, poflefs peculiar llruflure,
very different from that of the former. Their texture
is fibrous, and the fibres arranged and interwoven, fo as
to form parts called organs, by means of which they
carry on certain operations or funElions neceffary for
their prefervation, or for the reproduction of the fpecies.
Hence thefe have been called organised bodies, while
the others have been denominated brute or inorganic
matter. See NATURAL Hi/lory, N° 7.
The component principles of organized beings are
much more numerous in each individual than thofe of
inorganic matter, though their abfolute number in the
former clafs is fmaller than in the latter. In order to
prefent, under a compendious point of view, the di-
Itinguilhing chara&eriltics of thefe two claffes of beings,
we Ihall give the following table.
Mobility,
o
S <
g o
*s
h£)
Jh
O
n
03
6 3
-Q
rC
e* £
£ *
<u aj
Repofe,
Aggregation,
Cohefion,
Gravitation,
Condenfation,
Dilatation,
Combination,
Diffolution.
' Imprellion,
Senfat ion,
Perception,
AffeCtion,
Sympathy,
Adion,
Locomotion,
Digeltion,
Circulation,
Refpiration,
Affimilation,
Accretion,
_ Reproduction.
4
-o
os
>
C*
Inertia,
Impulfion,
Attraction,
Affinity.
bo
4b
TO <U
> <J
.—1 s-
ez
Senfitive,
Motive,
Affimilative, and
Vital refiltance.
P-C TO
2 S
C4
C
TO <-M
bO O
^ 'T-i
4J TO
"2 w
OJ -Q
-
O In
-G
H
TO
6
.0
‘3
TO
bo
’ Extenfion,
Gravity,
Hardnefs,
Elafticity,
Fluidity,
Impenetrability,
Divifibility,
Expanfibility,
Permeability,
Figurability.
Regularity,
Individuality,
Spontaneity,
Senfibility,
ContraClility.
Irritability,
Expanfibility,
Corruptibility.
bC-C
G3 *3
u bo
O .£
.TO ^
’to
r
Cryftals,
Salts, v
<j Metals,
Stones,
Foffils.
Chap. I.
General
Phenomena
of Life.
bO
w
"O.
O.^
3
« bO
3 G
.2 «
.TO ^
TO ^
-G
o >
Man,
Mammalia,
Birds,
Reptiles,
Serpents,
Fifhes,
Mollufca,
Cruftacea,
InfeCts,
Worms,
Zoophytes,
_ Plants.
The differences that are found to prevail between Effedts of
organized beings and inorganic matter, have always life,
been attributed to fomething of a fuperior nature, called
vitality or life. This term life forms one of thofe Am¬
ple ideas which it is difficult to define, and as all un-
derftand the meaning of the expreffion, a definition is
the lefs neceffary 5 but if it be required, it cannot be ex-
preffed more accurately than in the language of Bichat,
who calls life the fum of thofe fun&lions which refjl
death. In ffiort, life is belt defcribed by the effeCts pro¬
duced on a body while it refides in it, contrafted with
thefe appearances wffiich take place in the fame body
when life is no longer prefent. ^
One of the moft general effeCts of the prefence of lifeRefittance
is, as we have faid, the refiftance which living beingst0 c^eiri^ci^
are by it enabled to oppofe to the operation of externalchanse'
agents; and this is moft remarkably leen with refpeCt to
temperature. Every living being poffeffes, in a greater
or lefs degree, the power of preferving nearly an uni¬
form temperature, which is always a few degrees great¬
er than that of the medium in which it lives. In
plants, this power feems to exirt but in a low degree.
Some of the lower animals which inhabit the air, parti¬
cularly infeCts, poffefs it much more completely. The
great heat generated in a hive of bees is a familiar il-
luftration of this. In birds this property is very re¬
markable, the heat of their bodies being greater than
that of any other fpecies of animals. The heat of fifties,
worms, and of moft reptiles, very little exceeds the
temperature of the medium in which they refide \ but
when the water in which fifties live is frozen, they are
capable of refitting, for a long time, the confequences
of the diminithed temperature. The power which ma¬
ny animals poffefs of refitting high degrees of heat with¬
out any confiderable increafe of their own temperature,
feems ftill more remarkable, and probably led to the
fable of the falamander, which was fuppofed able to en¬
dure the heat of fire, and even extinguifti it, i\hen
thrown in for that purpofe. . „
Life feems to pervade almoft every part of a living Degrees of
being. In animals, every part except the cuticle, hair, vitality,
and nails, exhibit marks of vitality j but it feems to be dif-
tributed
5«
Functions
of living
beings.
57
Motion.
Chap. I. P H Y S I
General tributed through tbofe parts in a different manner in
^^r°ffena,the various tribes of organized beings. In plants, and
i . ^ ' . in a few of the inferior animals, as the zoophyta, it
feems to exift independently in almoff every part. A
bud, flip, or fucker, torn from the parent plant, and
inferted within the bark of another plant, or placed
■within the earth, in favourable circumftances, vegetates,
increafes, and in due time becomes a perfefl plant, in all
refpe&s fimilar to the parent flock. If a polypus be
cut in pieces, each piece lives and grows, till it be¬
comes itfelf a complete polypus. If a worm be cut in
tw'o, fo as to leave one part with the head, and the other
•with the tail, each part becomes a perfeff worm, pof-
feffing both head and tail. As we afcend, howrever,
in the fcale of beings, we find life lefs equally and in¬
dependently diffufed. A part cut or tom from the bo¬
dy of moff animals quickly lofes its vitality j but this is
loft fooner in fome animals than in others. The head
of a turtle or a fnake is able to bite many hours or
even days, after it is fevered from the body ; and in the
former inftance, the animal feems for a long time to
experience little inconvenience from its lofs. The heart
of a frog is feen to move many hours after it is cut out.
The principal effefls of the prefence of life appear in
the exercife of thofe functions or actions by which living
beings preferve their exiftence, or reproduce their like.
One of the moft general properties of organized be¬
ings is that fufceptibility to motion, which is called ir¬
ritability, W’hich appears effential to life, and is poffef-
fed, in a greater or lefs degree, by every clafs of orga¬
nized beings. The motions of plants are fometimes
very remarkable, and approach very nearly to thofe
which take place in animals. The ftamina of the
cijlas helianthemum are feen to move in various direc¬
tions when the fun ftiines on them; the leaves of the
tmmofapudica (fenfitive plant), wThen touched by the
hand, or when irritated by the alighting of an infeft on
them, immediately contraft j the dioncea mufcipula
{Venus’s fly-trap), when a fly touches its leaves, clofes
the thorny fringes wdth which they are befet, on the pre-
fumptuous infeft, and crulhes it to death; but the mo¬
tions of the hedyfarum gyrans are the moft remark¬
able of all thofe that take place in plants. The leaves
of this extraordinary vegetable are feen in conftant mo¬
tion through the greateft part of the day, without the
intervention of any apparent external impulfe 5 and even
wrhen a branch is cut off and kept in water, the motion
of the leaves continues for many hours together. All
the plants which grow above the earth, expofe their
leaves and flowers to the warm funfhine, and when fitu-
ated in a place which is fupplied by light only from
one quarter, they gradually direft their branches to¬
wards that part by which the light enters. In ftormy
weather they retract their leaves, and fold up their
florvers, and when confined in the dark, their branches
retain the pofition which they had when laft expofed to
the light.
I'he motions of many of the lower animals, though
fufficiently apparent, are more obfcure than thofe of
plants. A mufcle or an oyfter feems to poffefs little
more motion than is neceffary to open and clofe the
valves of its (hell, and, no more than plants, has the fa¬
culty of conveying itfelf from place to place. This fa¬
culty of locomotion, which in all the higher claffes of
O L O G Y.
4%
animals is dependent on the will, will be fully confider- General
ed in the fecond chapter. Phenomena
The funftion which appears to be moft univerfally , otLltr' ,
diffufed in living beings, is digetlion, (including nutri- S3
tion) or that by which the fubftances intended for their Digeftion*
nouriflrmerit are aflimilated to the nature of the body
which they enter. This function varies confiderably in
the different claffes. Plants merely attradl water from
the earth in which they grow, by means of the fibrous
parts of their roots, whence it is conveyed by innumera¬
ble capillary veffels throughout the whole plant, in which
it appears partly to be decompofed, and partly to remain
in the ftate of wrater, diluting fome of the vegetable
principles, and thus forming the juices of the plant. In
fome of the inferior animals, digeftion feems to be al-
moft the only function which they are capable of per¬
forming. Thus, many of the zoophytes, as the polypi,
appear to be almoft entirely compofed of a ftomach, re-
fcmbling the finger of a glove, into which the aliment
is received, the nutritive part extracted, and the excre-
mentitious part thrown out by the fame opening, In
moft other animals, the alimentary canal has two diftinft
openings, one for the reception of the food, and the
other for the ejedlion of the excrement.
By fome animals the food is fwallowed entire, and
digeftion is performed by a Ample folution or trituratioa
in the ftomach ; wTile in others the mouth is furnithed-
with teeth, or other hard parts, capable of reducing the
aliment to a pulpy ftate, in order to render its further
digeftion more eafy and expeditious. In molt animals,
the food having undergone fome change in the digeftive
organs, is taken up from them by certain very minute
veffels, and carried to every part of the body ; but in
fome it appears rather to exude through pores in the fides
of the alimentary canal.
The fun&ion of circulation, by which the fluids are circulation*
conftantly moved through every part of the body, is not
fo general as either of the former fundlions. In plants
there is no proper circulation ; for although there are
numerous veffels by which w^ater enters into the fub-
ftance of the plant, and in which the peculiar juices of
the vegetable move, the motions of thefe fluids are not
uniform, and do not tend tow-ards one centre. The
fame defedlive circulation appears in many of the infe¬
rior animals, as in zoophytes and inlefls. As we rife,
however, to the higher claffes, we find a perfeft circu¬
lation. In thefe there is always a peculiar organ from
which the fluids are conveyed to the reft of the body,
and to which they again return in a perpetual round.
In fome animals this central organ is Angle, while in
others it confifts of tw^o fimilar organs joined together,
from one of which the whole of the fluids proceed thro’
one particular organ in a lefier circulation, and thence
return to the other part, before they are diftributed to
the general fyftem.
All organized beings require more or lefs the prefence R r
of atmofpheric air for their fubfiftence, or at leaft for C 10B*
the due performance of the vital fun&ions. In fome,
the agency of this fluid is conveyed merely by pores up¬
on the furface •, as in plants, in which the leaves abforb
the air ; and in feveral of the inferior animals, as infedls
and worms, over the furface of whofe bodies are diftri¬
buted numerous openings, by which the air enters. In
animals of the higher orders there are peculiar organs
called^
46+
General called lungs or gills, through which air, or water con-
fL'ftna *-a^n^nS a*r» enters, and from which its beneficial influ-
i  i ence is imparted to the fluids which are circulating
through them. In general, thefe beings exift for a very
fliort time, when deprived of atmofpheric air, or when
the element in which they live is deprived of oxygen :
but in feme of the lower daffes of animals the abfence
of oxygen is much lefs injurious ; and there are inftances
of reptiles in particular having been preferved in a date
fufceptible of life and motion, while buried for many
years in the heart of a tree, or in the middle of a block
of done. Kefpiration, then, though in general necel-
fary to the continuance of vitality, may, in many tribes
of organized beings, be fufpended for a confiderable
time, without the principle of life being entirely de-
6! droyed.
Reproduc- A function equally general, and equally indifpenfible
tier*. with that of digedion, and one which forms another
charafleridic of living beings, is the fundlion of regene¬
ration, a function more peculiarly neceffary, as all orga¬
nized beings, though capable of refilling for a confider-
able time the operation of external agents, tend ulti¬
mately to corruption and decay ; and as they cannot,
like inorganic matter, be regenerated by a reunion of
their component principles, it w'as neceffary that they
diould polfefs the capacity of producing, while in exif-
tence, a creature fimilar to themfelves, to fupply their
place in the fcale of being.
It has been a very general opinion among naturalids,
that all living beings, both plants and animals, originate
from feeds or eggs produced by the parent. This, al¬
though very generally true, is not a univerfal faef.
Mod plants, indeed, with which wre are acquainted, ap¬
pear capable, in their natural date, of producing feeds,
which form the embryo of a future plant. But in a
great many of them new plants are obtained from buds,
flips, or fuckers, furnifhed by the parent. In fome ani¬
mals too, as the polypi, reprodublion may be effecled
by dividing the parent into feveral pieces j and even the
natural generation of thefe animals is performed by
protuberances which grow7 from the body of the parent,
and leem to drop off fpontaneoufly, when capable of an
■independent exidence.
There are two driking differences in the manner
by which living beings are generated. In fome, tw7o
didinft fets of organs are neccflary, and by the mutual ac¬
tion of thefe generation is effefted ; while in others, as in
the indances we have mentioned of the polypus, this a£t
of copulation appears to be unneceffary. Almod all
plants poffefs didindt fexual organs, and in mod both
male and female organs are fituated in the fame indivi¬
dual. In thefe plants the female ovum is impregated
by a very fine powder, which is contained in part of
the male organs, and is applied to thofe of the female.
We are fully convinced of the necedity of the vegetable
copulation, by obferving that the females of thofe plants
which have the fexual organs fituated in didinft indivi¬
duals are not capable of producing fruit, or at lead do
not produce this in perfefuon, if they are excluded from
the influence of the male ; and that an artificial Im¬
pregnation may be brought about by bringing the male
and female organs in contaft. Many animals are her¬
maphrodite j and among thefe the individuals of fome
fpecies generate wdthout the afliflance of another indi-
j;idual of the fame fpecies. This appears to be the cafe
2
Ghap. I.
with the bivalve dtell-filh. Others again, as fnails, and 'General
mod of the mollufca, which crawl upon the earth, copu- Aenomunai
late reciprocally, or each individual performs the dcu- , ■'■‘rL-Sc-
ble office of male and female. In mod animals, how* v ~J
ever, the fexes are dittincf, and probably a real henna*
phrodite in the fuperior claffes never exided. Another
driking difference with refpetd to generation in animals
is the more or lefs perfect date in which they bring
forth their young. A large proportion of animals,
among which are the infect; tribe,.fiffies and birds, pro¬
duce eggs, which are aftertvards hatched by the heat
of the parent, or by that of the fun. Other claiies
again, as fome of the amphibia, and the whole of llie mam¬
malia, carry their young for a certain time within an
organ dedined for that purpofe, from which they are ex¬
cluded in the date of perfect animals. ^
The lad function which we lhall here notice, is fen- ctnfauon
fation. This appears to be lefs general than any which
we have hitherto mentioned. It has indeed been fup-
pofed by many philofophers and naturalids, that plants
poffefs a degree of fenfibility •, and this opinion has been
lately avoured and drenuoufiy fupported by the elegant, but
enthufiadic author of the Botanic Garden, and the Loves
of the Plants. That plants poffefs a fufeeptibility of re¬
ceiving impieffions, and in cor.fequence of that of be¬
ing roufed into action by external dimuli, we ffiali
readily admit, and diall hereafter affign to this fufeep¬
tibility its due importance ; but as there is no reafon to
believe that it ever produces fenfation, we mud not con¬
found it with the fenfibility of animals 5 nor is the diffi.
culty of explaining fome of the fimetions of vegetables,
without reforting to the hypothefis of a vegetable fenfo-
rium, a fufficient reafon for inveding them with this fa¬
culty. It has even been doubted whether fome of the
inferior animals, as the zoophytes, poffefs this function,
as nervous fibres have not yet been detected in their or¬
ganization. It is probable, that there is a regular gra¬
dation in the tribes of organized beings with refpebt t®
fenfation, as w7ell as the other fun ft ions •, and though we
have not been able to difcover all the links of this
chain, thefe will probably, as our knowledge of nature
increafes, come more into view, and we ihall then be
able to reconcile many circumdances which we cannot
at prefent comprehend.
With refpeft to the varieties that take place in the
number and degree of the external fenfes, as poffeffed
by the various claffes of animals, we may refer the
reader to what has been faid on that fubjeft in the
fird chapter of the comparative part of the article Ana¬
tomy.
The duration of life is exceedingly various. We Quriftiou
know that there are animals wffilch live but a few hours, life,
as the infefts called ephemerce; and that others, as the
elephant, the raven, and the pike, may exid for a cen¬
tury. The term of life allotted to plants is alfo vari¬
ous; fome live only for a year, and are hence called an¬
nual plants; others exid for two years, and are called
biennial plants ; while a few7 furpafs in longevity any
thing with which we are acquainted in animated na¬
ture. Thus, the oah is faid to require 100 years, in
order to acquire its full maturity; to retain its perfefl
vigour for the like term, and to complete at lead a third
century before it entirely decays. The chefnut is a dill
more remarkable indance of vegetable longevity. The
account of the gigantic chefnut on Mount iEtna, given
by
PHYSIOLOGY.
Chap, I.
P H Y S I
General
Phenomena
of Life.
64
Gaufe of
life.
. *5
Opinions
refpecting
the vital
principle.
66
John Hun¬
ter.
Goodwin.
by Brydone and other travellers, which has exifted for
many centuries, muft be familiar to moll of our readers.
We have hitherto confidered life as diiplayed in the ex-
ercife of functions j but it may exilt independently of
this exercife, or it may lie dormant for a conliderable
time, till called into adlion by particular circumllances.
Every one knows how long a feed or an egg, when ex¬
cluded from heat, air, and moifture, wall retain the fa¬
culty of producing a plant or an animal. The only
proof we have, that this faculty Hill exifts is, that when
we place the feed or the egg in circumftances favour¬
able to the developement of the embryo which it con¬
tains, the procefs of generation goes on, till the plant
or the animal is excluded. We know alfo, that after
an organized being has commenced the exercife of its
funftions, this exercife may ceafe for a time, or at leaf!
become almoft imperceptible, while yet the vital power
fhall remain fufceptible of reviving its activity at a fu¬
ture period. We then fay that the animal or vegetable
is in a torpid ftate. On this part of the hiftory of life
we lhall not enter at prefent, but fhall defer the conlidera-
tion of it till we come to treat of deep and death.
The above is a hafty comparative (ketch of the func¬
tions exercifed by the various tribes of organized beings.
It is fufficient to (how, that there is in thefe beings a vi¬
tal power which completely diftinguilhes them from
brute or inorganic matter.
A queftion which naturally arifes in every thinking
mind is, What is the effence of life, or on what does it de¬
pend ? Though we profefs ourfelves unable to anfwer
this queftion in a fatisfaftory manner, and believe that
all who have hitherto attempted to do fo, have failed in
their attempts, it may be acceptable to moft of our
readers to know the opinions of the moft refpeftable wri¬
ters on this abftrufe fubjeft. Thefe, therefore, we ft 1 all
briefly ftate.
Thefe opinions have chiefly refted on the queftion,
whether life be an independent, immaterial principle, or
merely a phyfical or chemical modification of matter.
We have already, in the hiftorical view which wre have
given of the progrefs of phyfiology, mentioned fome of
the more remarkable dodtrines refpefting the principle of
life that have been delivered prior to the 18th century ;
we fhall here, therefore, only mention thofe which have
been maintained fince that time.
Mr John Hunter, in his valuable treatife on the blood,
fuppofes the principle of vitality to exift in that fluid, or
that the blood has life ; and has founded this dodlrine
chiefly on the following proofs. Firft, It unites living
parts, when it is effufed between them. Secondly, It
becomes vafcular like other living parts; its tempera¬
ture as it flows from the veffel, is always equal in the
moft oppofite temperature in which the body can bear
expofure. Thirdly, It is capable of being a£ted upon
by a ftimulus, as is the cafe when it coagulates. Fourth,
Paralytic limbs, though deprived of motion and fenfation,
are yet nourifhed and preferved alive by the blood cir¬
culating through them.
Mr Huflter’sidea of the vitality of the blood is merely
the revival of one of the oldeft phyfiological doftrines
on record ; namely, that delivered to the Ifraelites by
Mofes, that in the blood is the life of an animal.
Dr Goodwin, in his work on the connexion of life
with refpiration, is of opinion, that the heart is the great
feat of the principle of life in all the more perfeft ani-
VOL. XVI. Part II.
O L O G Y.
465
mals j and that the contractions of the heart with the General
ordinary ftimulus is the only mark of the preience of this i
principle j that when the heart contracts under fuch cir-1 ' y ‘
cumftances, the body is alive ; when not, it is dead.
Life he therefore defines to be the faculty of propelling
the fluids through the circulatory fyftem. According
to him, the external concomitant circumftances which
operate upon the body in health are heat and refpiration,
which excite the vital principle to action ; and when¬
ever the functions of an animal are fuddenly fufpended,
and the body puts on the appearance of death, it is al¬
ways in our power to determine whether it be really
dead, by reftoring the temperature, and by inflating the
lungs with proper air. He is of opinion, with fome
others, that there are no means of determining the abfo-
lute deprivation of the vital principle but by the prefence
of putrefa&ion.
It has lately become fafliionable to confider life as the
confequence of certain chemical changes, which are go¬
ing on in the body ; an opinion which is chiefly fup-
ported by Hufeland, Girtanner, and Humboldt. gg
According to Plufeland, life is a chemico-animal flame, Hufeland.
to the produdlion of which oxygen is abfblulely necef-
fary, and the vital power is the moft general and power¬
ful of all the powers of nature. He confiders it as the
caufe of organization, and as poflefling the following
properties.
1. It has a greater affinity to fome organized bodies
than to others; thus, the polypus may be cut in pieces
without being divefled of it, and a decapitated tortoife
or a frog deprived of its heart will live a long time af¬
ter j whilft to the human body, or a quadruped, it
would be inftant death. According to this phyfiologift, it
is a general rule, that the ftronger the affinity between
life and an organized being, the more imperfed! is the
animal ; hence the zoophytes, whofe whole organization
confifts in a mouth, a ftomach, and a gut, have a life
exceedingly tenacious, and difficult to be deftroyed.
2. It is in greater quantity in fome organized bodies
than in others. In general, cold-blooded animals live
longer than thofe with warm blood. 3. It frees bodies
from the chemical laws of inanimate matter, and trans¬
fers the component parts of a body from the phyfical or
chemical to the organic or living world. 4. It prevents
putrefa&ion, for no organized body can putrefy unlefs
deprived of life. ^
Humboldt is of opinion, that the degree of vitality Humboldt,
depends upon the reciprocal balance of the chemical af¬
finities of all the elementary parts of which the animal
body is compofed.
Some phyfiologifts of the prefent day deny the exift- Cuvier,
ence of the vital principle altogether. “ The idea of life,
(fays Cuvier), is one of thofe general and obfcure ideas
produced in us by obferving a certain feries of pheno¬
mena, poffeffing mutual relations, and fucceeding each
other in a conftant order. We know" not indeed the
nature of the link that unites thefe phenomena, but we
are fenfible that a connexion muft exift ; and this con¬
viction is fufficient to induce us to give it a name, which
the vulgar are apt to regard as the fign of a particular
principle, though in fadt that name can only indicate
the totality of the phenomena which have occafioned its
formation.”
Dr Ferriar, in his obfervations concerning the vital Fcrriar.
principle, thinks, that fome dire£t arguments may be
3 N brought
466
5 General brouglit againft the general fuppohtion of an independ-
1 ent principle. Thefe arguments he divides into
i . two kinds, viz. refutations of the general proofs offered
in fupport of the vital principle •, and inftances of the di¬
rect iniluence of the mind and brain over what is term¬
ed the independent living principle. The great proofs
for the fupport of a vital principle are, the con trail ion
of mufcles feparate'd from the body on the application of
ftimulants ; the performance of the vital and involun¬
tary motions without any exertion or even confeioufnefs
of the mind, and the birth of full-grown foetules delli-
tute of a brain. In all thefe cafes, fomething is alleged
to operate, independently of the mind, in producing
mufcnlar motion.
13 r F erriar, in anfwer to the fir ft argument drawn
from the contraction of feparated mufcles, affirms, it
may be laid, lit, JLhat the power of contrailion, in a
feparate mufcle, is loft before putrefaction takes place,
i. e. before the deftruition of its texture ; but if its vita¬
lity depended on its texture, this ought not to happen.
2dly, 'i'he power of contraduon, in a feparated mufcle,
is ftrongeft upon its firft feparation, and becomes weak¬
er by degrees} therefore, the contracling power feems
to have been derived from fome fource from which it is
detached by the excilion of the part. 3dly, Irritation
of the ?nedulla oblongata, or of the nerves fupplying par¬
ticular mufcles, occafions ftronger contradlions than irri¬
tation of the mufcles themfelves ; and Dr Whytt fur-
nifhes an experiment on a frog, diredlly proving, that
the adlion oi feparated mufcles depends upon the ner¬
vous energy. 4thly, Dr Haller himfelf is obliged to make
on this fubjecl a conceffion fufficientto deftroy his favou¬
rite hypothefis ofthe vis injita. jthly, When a paralytic
limb is convulled by the electric fiiock, the motion ne¬
ver takes place without the patient’s confeioufnefs. In
this cafe there is no diiiindlion between the vital princi¬
ple, and that exertion which in voluntary motion is al¬
ways attributed to the mind. See Chap. iii.
In anfwer to the fecond argument, in favour of a vi¬
tal principle, drawn from the performances of the vital
and other involuntary nfiotions, Dr Ferriar contents him¬
felf with only cbfervmg, that, allowing the organs of
thofe motions to be fupphed with nervous energy, their
motions may be very well accounted for by the ftimulus
of their contained fluids.
1 he force of the third argument, drawn from the
want of a brain in full-grown feetufes, is taken off by
Dr Whytt, who remarks, that as the heart is fometimes
wanting in full-grown foetufes, the argument would
equally prove, that the heart is not neceflary for the
continuance of circulation, as that the brain is not ne-
ceflary to the fupport of the fyftem. Accordingly,
foetufes born without a brain do not, in general, furvive
birth.
Befides the general fuppofition of an independent liv¬
ing principle, an inference has been drawn from fadls,
oJ a nervous energy independent of the brain. By this
term is meant, iliat condition derived from the brain to
different parts of the body, by means of which they be¬
come capable cf motion. To fhow, by direct proof,
that there is no independent vital principle; Dr Ferriar
obferves, 1. That it is juftly urged by Dr Monro againft
the dodlrine of the vis infila, that there is too much de-
fign in the a&ions of different mufcles, affe&ed by dif-
Chap.
ferent Jiimuli, to be the cfica; of mere mechanifm. General
I hus, when the hand or foot is burnt, or otherwfife fud- Phenomena
denly injured, the mufcles on the part immediately Hi- °‘
mulated are not thrown into adlion, nor the mufcles on v '
tue floe nutated, but their antagonifts con trade, immedi¬
ately, and ftrongly. Now, if the inftantaneous aclion
be in this cafe chiefly produced by an effort of the mind,
the fuppofition of a diftindl vital principle is fuperfluous:
if it be faid to be produced by a living power independ¬
ent of the mind,, then there muft be a rational power in
the body independent of the mind, which is abfurd.
2. I he ftate of the vital and involuntary motions is con-
fiderably affedted by the ftate of the mind, which equal¬
ly difproves the exiftence of a feparate vital principle,
and pioves the dependence of the nervous enerpy upon
tiie brain. 3- Madnefs, it is well known, is frequently
produced by caufes purely mental, and in perfons appa¬
rently in good health 5 and, as the patient’s fenfibility
to very powerful ftimuli is much diminilhed in maniacal
cafes, they afford another proof of the fubordination of
the nervous energy. 4. It has been obferved, that in
paralytic cafes, motion is frequently deftroyed, while
fenfe remains. As the caufe of palfy almoft’always re-
ftdes in the brain, this fadt appears equally inexplicable
on the opinion of a diftmdl living principle, or of a ner¬
vous energy, independent of the brain. 5. When nerves
are regenerated, alter being cut through, fenfation and
voluntary motion are not always reftored to the parts be¬
neath the divifion : the refloration was never made in
J3r Monro’s experiments. But, on the fuppofition of a
diftindt nervous power, the nerve, after its re-union,
ought to refume all its offices. 6. Dr Whytt afferts,
that when tne fpmal marrow of a frog is deftroyed,
after decollation, no contradtion can be excited in the
limbs, .by cutting or tearing the mufcles. Such are
the fadls and arguments which Dr Ferriar brings a-
gainft the opinion of a diftindl living principle ; and
he thinks, that their inveftigation appears to lead us
back to the brain as the fource of fenfibility and irri¬
tability.
In the life of Dr John Brown, we have given an ac-Rufl^*
count of the dodtrine, of life being a forced ilate. This
dodlrine appears to have been firft delivered by Dr Cul¬
len, though he afterwards retradted it. Of late Dr
Ruffi of Philadelphia, in his LeEiurcs on animal life,
has advanced many arguments in favour of this dodlrine.
He includes, in animal life, three properties as applied
to the human body, viz. motion, fenfation, and thought;
and thefe, when united, compofe perfedt life. It may
exift without thought or fenfation ; but neither fenfation
nor thought can exift without motion. He affirms, that
the loweft degree of life exifts even in the abfence of
motion. He firft confiders animal life as it appears in
the waking and fleeping ftate, in a healthy adult ; and
afterwards inquires into the modification of its caufes in
the foetal, infant, youthful and middle ftates of life, in
certain difeafes, in different ftates of fociety, and in dif¬
ferent animals, and lays down the following propoft-
tions :
1. Every part of the human body, the nails and hair
excepted, is endued with fenfibility or excitability, or
with both.
2. The whole body is fo formed and connedted,
that impreflions made in the healthy ftate upon one part
excite
PHYSIOLOGY.
i
Chap. T.
G;neral excite motion or xenfation, or both, in every ether part
of the body.
> ' . 3. Life is the effefl: of certain ftimuli a£Hng upon the
feniibility and excitability, which are extended in differ¬
ent degrees to every external and internal part of the
body ; and thefe llimuli are as neceffary to its exiftence
as air is to flame.
He continues to obferve, that the action of the brain,
the diaftole and fyftole of the heart, the pulfation of the
arteries, the contraftion of the mufcles, the periilaltic
motion of the bowels, the abl’orbing power of the lym¬
phatics, fecretion, excretion, hearing, feeing, fmelling,
tafte, and the fenfe of touch, even thought itfelf, are all
the effects of itimuli a cling upon the organs of fenfe and
motion.
Thefe have been divided into external and internal.
1. The external are light, found, colours, air, heat,
exercife, and the pleafures of the fenfes.
2. The internal ftimuli are food, drinks, chyle, blood,
tenfion of the glands which contain fecreted liquors, and
the exercife of the faculties of the mind.
Life, therefore, (according to the hypothefis of Rufti)
even thought itfelf, is merely a quality redding in the
component parts of a material fyftem, dependent upon a
peculiar organization, by which it is enabled to aft, or
in fome ways to move on being ftimulated or excited.
Hence life can never be inherent in a fimple uncom¬
pounded fubftance, nor in a particle of animal matter;
and it the flimulus be withheld from a living fyftem be¬
yond a given time, all motion, fenfation, and thought,
muft neceffarily be extinguifhed.
73 _ Inftead of one vital principle, fome phyfiologifts have
Vital pnn- fUpp0feci the exiftence of feveral in the fame body; and
fed by feme ^rom t^e phenomena that take place in fome organized
to be divifi- beings, as the reunion of parts that had been feparated,
Isle. the reproduftion of others that have been loft, and the
feparate exiftence of the divided parts of fome worms
and zoophytes, it was formerly the opinion of a celebra¬
ted ledlurer on anatomy, that the vital principle was
really divided. From more confiderate and extenftve
inquiry, however, he is now of opinion, that the irrita¬
bility on which thefe phenomena depend, is never the
direft or immediate operation of the vital principle,
but only the confequence of its operation ; and in no
cafe exclufively the confequence, but the confequence
likewife of other operations proceeding from a number
of different caufes; and hence it is that a vital princi¬
ple may often- exift where it cannot operate in a fenfible
manner, from the want of auxiliaries ; and hence it is,
likewife, that its effefts may often be continued, at leaft
for a while after its departure.
"With regard to the portions of plants and polypi that
continue to live in a feparate ftate, affume the form of
their refpeftive fpecies, and propagate their kind, they
will be found, on a elefe examination, to have been ori¬
ginally complete fyftems 5 many of the'plants and many
of the polypi that were ufually conftdered as fimple in¬
dividuals, not conftituting one animated fyftem, but ra¬
ther a congeries of animated fyftems,—a congeries, too,
which after all is nothing more than a fpecies of fociety,
^THarclay where animated beings are affociated together for mu-
tual proteftion ; fuch as we fee among men in 3 city j
tions, D. am?n§ kees in their cells, which, in point of form, are
265.’ ’ fimilar to plants f.
PHYSIOLOGY,
Chap. II. Of Set if at bn.
As all living beings are fo related to each other, and jsj-ecefpty 0f
to the inanimate objefts of nature, as tobecapabidof de-fenfibility
riving benefit, or receiving injuries, from the one orto or£ianIZ-
from the Other; it feems neceffary that they fhould pof-et^ beir^s‘
fefs the faculty of perceiving the proximity of the be¬
neficial or injurious objeft, that they may avail them-
felves of.the benefit -which it holds out, or avoid the
danger which it threatens. Accordingly, we find that
all organized beings enjoy in feme degree the capacity
of receiving imprefjions, which we think is proved by
the motions which take place in them when affefted by
external agents. When a plant expands its flowers to
the fun, or turns', as it were, its back to the blaft; when
it ftietches out the fibres of its roots io imbibe the di-
ftant moifture, or direfts its branches to the only chink
by which it can receive the light of day ; we think
thefe motions are the confequence of that capacity of
receiving itnprejfioris, or of being rouzed to aft ion by
Jiimuli; we think that this may be conceded, without
having recourfe to the influence of mind, or even the
medium of a nervous fyftem ; wTe do not believe that the
grafs wTe cruth beneath our feet is fenfible of pain, nor
do w-e fupp&fe rvith the poet, that
E’en the poor beetle that we tread on,
75
In mortal fufferance feels a pauv as Treat
As. when a giant dies” 
but we are of opinion, that even in the leweft tribes Senfiuvity.
there is a degree of that faculty, which in the higher"
orders of animals we cA\ fenfbiliiy, and which we {hall
here, after a lefturer on the animal economy in Lon¬
don, denominate fenfitivity. This inferior degree of
the fenfitive faculty we ftiall fuppofe to be poffeffed by
plants, zoophytes, and animalcules, or thofe organized
beings in which we can perceive no marks of a nervous
fyftem ; while we {lu ll confine the term fenfibility to all
other claffes of animals.
Thefe faculties wre confider as qualities of living bodies,
while w’e regard fenfation, like perception, as a quality
of mind. We leave it to the metaphyfician to mark the
line of diftinftion between fenfibility and fenfation, and
to (how how the one arifes from the other. See Me¬
taphysics, Part I. chap. 1.
The organs of fenfation confift of the brain propel-Nervous
ly/0 called, the cerebellum, the medulla oblongata, the fyfte:*.
fpinal marrow, the nerves, and ganglia together form¬
ing what is called the nervous fystem. Thefe parts in
the human body have been deieribed under Anatomy.
For an account of thefe organs in the inferior animals,
we muft refer to the leftures of Cuvier, vol. ii. or the
Comparative Anatomy of Blumenbach.
In refpeft offenfbility the animal is only paflive ; but
vAxtn fenfation is produced, he becomes aftive, in as
much as the organs of the external fenfes are then
brought into aftion. It is by means of thefe fenfes
that the animal receives intelligence from without. \Ve
{hall therefore examine thefe before we mention the
phenomena of fenfation in general.
I. O f Feeling.
The moft general of all the fenfes, and the moil wide-Feelu l
3 N 2 ly
468
Of
Seiifition.
73
79
Organs.
So
Nature of
touch.
P H Y S I
ly dliFufed over tlie body of an animal is that of touch
or feeling. Animals that poiTefs fcarceiy any other
fenfe feem always to have that of touch. It is doubtlefs
by this that polypi, ciBinice, and other water animals,
perceive the approach of their prey, or are warned of
impending danger, from the agitation of the water that
is communicated to their bodies. Indeed fo general is
this fenfe, that fome phyfiologifts think we may reduce
all others to it as a genus; and fuppofe that fmelling,
tajiing, hearing, and feeing, are only fpecies of feeling.
This reference is not uncommon in ordinary fpeech,
as it is not unufual to talk of feeling a fmell.
By touch, taken in its ordinary limited fenfe, we per¬
ceive the more ftriking external qualities ©f bodies, as
figure, hardnefs, foftnefs, roughnefs,fmoothnefs, moifiure,
drynefs, heat, cold; of all which, except figure, we
could fcarcely form any idea by the other fenfes. There
is probably no fenfe that can fo well fupply the place of
others as that of touch ; and it is particularly acute in
thofe who have loft their fight or hearing. See the ar¬
ticle Blind, efpecially the Appendix.
The organs of touch are the Ikin and its productions,
or rather the nervous papillae (fee Anatomy, N° 76.)
that form fo large a part of the true Ikin. As many
animals, however, have the body fo enveloped in a fca-
ly, fhelly, or hairy covering, as to prevent the aflual
contaCt of the body by external objeCts, there are other
organs that feem deftined to fulfil this office. In man,
the points of the fingers and the lips are the molt deli¬
cate feeling organs 5 in many quadrupeds too, the lips
feem to poffefs an exquifite fenfibility, and in fome, as the
rhinoceros, the upper lip is lengthened out as if to ferve the
purpefe of a hand. The prolonged fnouts of the tapir,
the Jhrew, the mole, and the hog, feem to anfwer the
fame purpofe 5 and the exquifite fenfibility and flexibi¬
lity of the trunk of the elephant is well known to fit
that organ for almoft all the purpofes to which the hu¬
man hand can be applied. The tail, in fome fpecies of
monkey, oppofum and ant-eater, and in fome reptiles,
feems to poffefs a high degree of fenfibility. In fome
animals, as the cat, the whilkers are employed as or¬
gans of feeling, as we know that thefe are erefted when
the animal is palling through a narrow hole. Several
fpecies of fifties have cirri and tentacula, which they
feem to ufe as fingers in afeertaining the approach of
their prey •, and in infefts, the antenme and the palpi
are evidently organs of feeling, as are the arms, the tufts,
and tentacula offea-fiars, fea-urchins, aBinice, medufee,
and many zoophytes.
Moll of the aftions of external bodies on fhe furface
of the animal body, are merely mechanical, though the
fenfations which they communicate may often be the
effeCls of a chemical change in fome of the feeling or¬
gans, and this change can be produced only in confe-
quence of the power of Ample preffure, to form or de-
ftroy fome of the combinations that take place in the
animal fyltem. The fenfations which appear molt evi¬
dently to arife from a chemical change in the organs,
are thofe that give notice of a change of temperature.
When a body that has a temperature below that of the
animal, comes in contaCf with the furface of this latter,
we know that it abftraCls from that furface a part of its
caloric, as by the contaCt it gradually acquires the
temperature of the animal j unlefs, indeed, it be fo large
and fo cold as altogether to deftroy life. As, however,
O L O G Y. Chap. II
the refiftance which the animal body gives to a too Of
great change of temperature, generally confines this Senlation.
change to the furface of the body ; there muff be fome- v
thing more than a mechanical or a chemical aftion, or
the lenfe of feeling muft depend chiefly on the vital prin-
ciple. ^ 81
As the fenfe of feeling, from its general diffufion, Uuiverfali-
may be confidered as the moft effential of all the fenfes; fy of feel-
its degrees of perfection have confiderable influence onin£-
the nature of different animals.
Of all vertebral animals, man feems to poffefs this
fenfe in the moft perfeCt degree } but among the inverte-
bral animals, the touch feems to improve as the
other fenfes degenerate } and thofe animals which appear
to have no other fenfe, poffefs this in fo exquifite a de¬
gree that they feem to feel even the light.
Dr Darwin thinks it probable, that the animal body
is furnifhed with a diftinft fet of nerves for the fenfation
of heat and cold. We do not fee the neceflity of this,
as we think that this fenfation is very naturally reduci¬
ble to that of feeling.
To this head naturally belongs the confideration ofSenfibility
what parts of the human body poffefs fenfibility, andoftheani-
what are infenfible. This difeuffion is curious, andma^bo^y*
fome time ago exercifed the ingenuity of two very able
phyfiologifts, Haller and Whytt ; between whom it
gave rife to a long and warm difpute. We cannot pre¬
tend to enter into the merits of this controverfy, for an
account of which we refer our readers to Dr Whytt’s
Physiological EJfays, and to the Principes de Physiologic
of Dumas, tom. ii. part. Hi. feCI. 1. chap. 1.
The general refult feems to be, that many parts will
appear fenfible or infenfible, according to the nature of
the ftimuli applied to them, and that many of thofe parts
which in their natural and healthy ftate appear infufeep-
tible of pain, are when inflamed or otherwife altered by
difeafes, highly fenfible 5 and that the brain, wdiich is
confidered as the centre of all fenfation, and the punc¬
ture or laceration of which is attended with moft dif-
trefling fymptoms in other parts, is to ordinary ftimuli
as infenfible as the cuticle or the nails. See alfo on this
fubjeCl, Bichat “ Anatomic Generale,” tom. i. p. 161.
— 167.
The principal morbid affedions of this fenfe, are pain,
itching, and want of feeling; for an account of which
fee Medicine, N° 77. The fundions of the Ikin, in¬
dependently of its ufe as an organ of touch, will be con-
fidered in twTo of our fucceeding chapters.
2. Of Tafiing.
O «
This fenfe is the moft nearly allied to feeling ®fTailing,
any of the other fenfes, and therefore very properly
comes under our confideration after that fenfe. g „
The principal organ of tafte is the tongue, efpecially Organs,
at its upper furfkce, point, and edges ; but it alfo extends
to the lips, the palate, and the velum pendulum palati.
The tongue is not abfolutely neceffary to tafte, as ap¬
pears from a cafe mentioned by Juffieu, of a perfon wdio
had only a flelhy tubercle in place of a tongue, and yet
poffeffed the fenfe fufficiently perfed.
The feveral parts of the organs of tafte are not equally Different
fenfible to every fapid body *, the tongue feems to be more organs vari-
particularly affeded by faline and faccharine fubftances, affeft-
chiefly, however, at its'upper furface j the lips are faid to t ‘
be
Chap.
II. P H Y S I
Of be moft fufceptible of the tafte of hellebore, the palate of
Senfation belladonna, and the gullet of wormwood. The momor-
1 ■r~~* dica elaterium is faid chiefly to affedl the back of the
tongue, and colocynth its middle.
The greater or lefs perfection of this fenfe depends
the "erfec- much on ^ foftnefs, flexibility, and moiftnefs of thefe
tion oTutte parts. As man feems to poilefs thefe qualifications in a
depends. more eminent degree than moft other animals, fo, in the
natural unfophifticated ftate of the tongue, he probably
enjoys the benefit of tafte much more highly than they.
Such is the cafe with all young children, and with the
peafant, whofe iimple fare appears to be eaten with a
much greater relifli than all the delicacies of the volup¬
tuary, who muft have recourfe to various ftimuli to
enable him to derive gratification from even the daintieft
viands (a).
Tafte feems to be more exquifite when the fapid body
is ftrongly preffed between the tongue and the palate.
Tafte is alfo rendered more acute when the tongue is
ftimulated by various condiments, as pepper, mujlard,
which even, when not taken in fuch quantity as to be
very perceptible themfelves, evidently increafe the relilh
of the difhes which they feafon. Much alfo depends on
the nature and ftate of the bodies that are applied to the
organs of tafte. Thefe muft, in the firft place, be ei¬
ther fluid, or capable of folution in the faliva. They
muft alfo poffefs fome faline or acrid quality, to render
them capable of afting on the nervous papilla:. It was
formerly fuppofed, that faline bodies alone poflefled the
power of affe&ing the organs of tafte j and it was con¬
ceived by Bellini, that the different flavours of faline
bodies depended on the figure of their cryftalline par¬
ticles. M. Dumas has taken conftderable pains, and has
advanced feveral arguments, to fliow the abfurdity of this
hypothefis •, and we think has treated it with more feriouf-
n’efs than it deferves. That the different fenfations
which fapid bodies excite in our organs of tafte, depend
chiefly on a difference in their chemical nature, muft,
we think, be allowed, and fome have gone fo far as to
fuppofe, that the fenfation depends on fome chemical
affinity between the fapid body and the nervous fluid.
The impreflion which fapid bodies make on the or¬
gans of tafte is modified by age, fex, temperament, and
habit. We know that children are particularly pleafed
with fweet things, while high feafoned diihes and vinous
liquors are more palatable to people of a more advanced
age. Women, from various caufes, efpecially during
pregnancy, and when labouring under hyfteric affec¬
tions, have often very Angular taftes. People of a warm
and a mobile conftitudonare often affe&edby flavours that
are almoft infenfible to others ; and cuftom will render
palatable many fubftances, which, when firft tailed, are
rejedled with difguft.
"Befides the gratification afforded to animals by the
fenfe of tafte, this is fuppofed to afford one of the prin¬
cipal means of diftinguifhing between wholefome asd de¬
leterious fubftances. Indeed, with refpedt to the infe-
O L O G Y.
469
s?
Modifica¬
tions of
tafte.
88
Ufes of
tafte.
rxor animals, this difcriminating fenfe is feldom known Of
to fail, and in this inftance, they are fuperior to man, Senfation.
who is often deceived. There jre many poifonous herbs,
the fruits or roots of which have a tafte not unpleafant,
but which cannot be eaten with impunity.
On the morbid affections of tafte, fee MEDICINE,
N° 78.
3. Of Stnelling.
The fenfe of fmelling, like that of tafte, Is nearly al-Smelling*
lied to feeling, and is one of thofe by which wre become
acquainted with the mechanical and chemical properties
of external bodies. It is caufed by volatile particles
flying off from odorous bodies, and diffufed or diffolved
in the atmofphere, in union with which they enter the
noftrils and affedl the nerves of the fmelling organs. 50
It is difficult to afcertain whiat are the effential organs Organs:
of fraelling. We know that in moft animals which
breathe through lungs or gills, there is either a nofe, or
there are certain holes that ferve the purpofe of noftrils ;
but in many animals there is nothing fimilar to thefe,
and yet there is every reafon to believe that they poiTefs
the fenfe of fmelling in an exquifite degree.
Infe£ls difcover their food at a diftance. Butterflies
feek their females, even when inclofed in boxes $ and as
they are liable to be deceived by refemblance of colour,
it is evident that thefe infefts are guided in many cir-
cumftances by the fenfe of fmell. Thus the flefh-fly
(mufca vomitoria) lays its eggs on plants that have a
foetid fmell, imagining that it places them on corrupted
flefh, and the larvae which are thus produced perifh for
wTant of their neceflary food.
As the organ of fmell, in all animals which refpire
air, is fituated at the entrance of the organs of refpira-
tion, the moft probable conje£lure that has been propof-
ed refpedling its feat in infeils, is that of Barter, fines
revived by feveral naturalifts, w7ho placed it in the
mouths of the tracheae or air tubes. Befide many other
reafons that might be ftated in fupport of this opinion, we
may obferve, that the internal membrane of the tracheae
appears very well calculated to perform this office, being
foft and moiftened, and that the infe£ts in which the
tracheae enlarge, and form numerous or confiderable
veficles, are thofe which feem to poflefs the moft per-
fe£l fenfe of fmelling. Such are all the fcarabai, the
bees, flies, &c.
The antennae, which other anatomifts have fuppofed
to be the feat of fmelling in jnfefts, do not appear to
Cuvier to poffefs any of the requifites for that organ.
The mollufca, which refpire air, may alfo poffefs this
fenfation at the entrance of their pulmonary veffels ; but
it is not neceftary to fearch for a particular organ of this
fenfe in them, as their whole fkin appears to refemble a
pituitary membrane. It is everywhere foft, fungous,
and is always moiftened by a great quantity of mucous
matter. Finally, it is fupplied with numerous nervesr
which animate every point of its furface.
The
(a) It is generally fuppofed, that the fenfe of tailing is more acute in fome of the inferior animals than in*
man •, an opinion which is founded chiefly on the greater fize and number of i\\c papilla of the tongue in thofe ani¬
mals. It is fcarcely polfible to decide this point j but we fliould conceive, from the infinite variety of fubftances that
are occafionally fubjefted to the human palate, and from the extreme delicacy of tafte difplayed by fome indivit
duals, that man has the advantage of his brute neighbours in this fenfe,.
47°
Of The worms and foft zoophytes, and all the polypes,
Senfation. are probably in the lame fituadon. It cannot be doubt-
ed but that thefe animaKenjoy the fenfe of fmell. It is
chiefly by it that they dilcover their x’ood, particularly
the fpecies that have no eyes. Ariftotie remarked, that
certain herbs, which have a ftrong odour, were avoided
91 by cuttlejifhes and the oBopus.
Nature of Qf all the fubftances which affefl our organs of fenfa-
°nderftood.e t^0n’ oc*ours are ^ie underftood, though the im-
un er. 00 . pre^jons wbicb they make on the animal body appear
to be molt powerful and extenfive. Some bodies are al¬
ways odorous, becaufe the whole or a part of their fub-
ftancd, being volatile, it is conftantly flying off: others
become odorous, only under certain circumftances $ as
when a body containing a volatile principle in its com-
petition is decompofed by another that has a lefs affinity
for that principle, e. gr. when muriate of ammonia is de¬
compofed by quicklime.
Odours feem to be propagated in the air, much in
the fame manner as one fluid is diffufed through another.
Their motion is not diredl lilee that of light, nor is it
rapid or fufceptible of refle&ion and refraction like light
and caloric. The odorous particles of volatile bodies
may enter into combination with different fubftances, by
chemical affinity, and thus lofe their original properties.
In this way the effluvia of putrid meat are deliroyed by
freffl burnt charcoal, and the noxious exhalations from
peftilential apartments are removed by the vapours of
nitric or muriatic acid.
Thefe circumftances feem to prove that each fmell is
occafioned by a particular fubftance floating in the atmo-
fphere. There are others, however, which appear to
indicate that odour is not always produced in tins man¬
ner.
Several bodies yield a ftrong fmell for a great’Tength
of time, without fuftaining any fenfible lofs of fubftance j
fuch, for example, is mulk. Some 'odours are per¬
ceived when no evaporation can be obferved, as the
fmell which arifes from the fridtion of copper, that pro¬
duced by the fufton of a great number of bodies, and
even by the melting of common ice. In other cafes,
real evaporations produce no feniible odour; this may
be remarked on the difengagement of feveral gafes, and
even on the ordinary evaporation of water. Perhaps
thefe phenomena prove only that the force of fenfation
is not proportional to the quantity of the fubftance by
which it is excited, but that it depends on the nature
and degree of the affinity of that fubftance with the nef-
* Gtuxier. vous fluid.* The adtion of the greater part of odorous
fubftances on the nervous fyftem, is rendered manifeft
by a number of other effects befides the fenfation of
fmell •, fome produce faintings, others giddinefs, or even
convulfions. Some, on the contrary, ferve to remove
thefe diforders: indeed the greater part of medicines
act in general rather by their volatile and odorous parts,
than by their other principles ; and afford new proofs of
the influence exercifed in the animal economy by the
gafeous and impalpable fubftances, the greater part of
■which are doubtlefs ftill unknown to us.
We know not whether odours have a peculiar ve¬
hicle, befides the matter of heat, which is common to
them all in their quality of vapours or elaftic fluids.
We cannot explain why odours are agreeable or dif-
agreeable to us, nor why thofe that are difgufting to us
appear pleafing to other animals, and vice verfa. Though
Chap. II.
man and other animals arc generally pleafed with the Of
odour of thofe fubftances which ferve them as food •, yet Senfation.
when their appetite is fatisfied, this odour often be-
comes difpleafing to them. On the contrary, fome
animals appear to have a paffionate iondnefs for ftrong
Imelling iubltances which feem altogether ufelefs to
them. Thus cats are extremely fond of cat~mintr
and the frefh roots of valerian. In general, thofe
odours which are moft difagreeabie indicate that the
fubftances from which they proceed are injurious.
Thus venomous plants, putrid flefla, and poifonous mi¬
nerals, have commonly an unpleafknt odour. This rule,
however, is not univerfalj and the fenfe of fmell, like that
of tafte, is not an unerring guide to man, whatever it may
be to other animals.
It appears that the effluvia of odorous bodies are ca¬
pable of diffuftog themfelves through water as well as
air 5 for when thefe fubftances are thrown into water
as bait for fifli, we find that thefe animals are attra&ed
by the fmell from a coniiderable diftance. ^
The comparative phyfiology of this fenfe is very cun-Compara-
ous, though we cannot explain the reafon of the differ-dve
ences that we find to take place in the various tribes of-0^y.|0t
animals. Man in a ftate of civilized lociety, where he lmC inS’
may have recourfe to a great variety of means by which
to diftinguiflr the properties of bodies, has lefs occafion for
acutenels of fmell; but we know that favages are in
that refpe<St greatly his fuperiors. Their fmcll is. fo
acute, that like a blood-hound, they can feent their
enemy to a great diftance, and purfue his track with al-
moft certain fuccefs. Among birds and beafts of prey
we alfo find that acutenefs of fmell is a very general
property. Hyaenas, wolves, vultures, and ravens, can di-
ftinguifh the putrid carcafes on which they fe«l many
miles off-, and it is afferted by naturalifts, that jackalls
hunt in packs, and follow their game like hounds by the
feent. There is a curious diveriity in this refpedt among
birds, fome having this fenfe very acute, others very
blunt. We are told by Gattoni*, that the cock is fcarce-
ly affe£ted with the fmell of ammonia or hartfhorn,
while the duck is laid to avoid all powerful odours oifaCluT
whether agreeable or otherwife. We are not iliffici-
ently acquainted with the nature of the olfa&ory mem¬
brane, nor with that of the nerves diftributed to it, to
enable us to form an opinion refpefting the degree and
the kind of fenfations they procure to different animals.
It may, however, be at firft fight .prefumed, that all
things in other refpefls being equal, the animals in
which the olfaflory membrane is moft extenfive, enjoy
%he fenfation of fraell moft exquifitely 5 and experience
confirms this conje&ure. It would be curious to learn
why the animals which poffefs the fenfe of fmell in the
higheft degree, are precifely thofe which feed on the
moft fetid fubftances, as we obferve in dogs which eat
carrion.
4. Of Hearing.
The fenfe of hearing is mere important than any Hearing,
which we have yet noticed, but it appears to be lefs
generally diffufed.
By means of it we become acquainted with thofe pro¬
perties of bodies which fit them for making fepfible im-
preflions on the air, as hardnefs, elafticity, &c. j and thefe
impreffions on the air, when communicated to the or¬
gans of hearing, convey ^to cur mind the ideas of found.
By
P H Y S I O L O G Y.
Chap. II.
PHYSIOLOGY.
471
Of By tins fenfe wc derive two of the higheil gratifications
Senfation. that ive are capable of enjoying, viz. the pleafures of
converfation and of mufic ; and in this way moil animals
hold intercourfe with each oilier.
94 The organs of hearing diil'er exceedingly in the vari-
r^ans’ ous claffes of animals. The human ear and its appen¬
dages have been described in Anatomy, Part I.
chap. vi. feet. 4.; and for an account of thefe organs in
other animals, we mull refer to Cuvier's LeClures, vol. ii.
or the Comparative Anatomy of Blumcnbach, chap. xx.
Red-blooded animals without exception have evident
auditory organs ; and analogous parts are found in
many of the white-blooded. In a great number of the
inferior clafles, however, no fuch parts have been afeer-
tained, though it is certain that many of them do really
hear. In all thofe in wdiich theie organs have been de¬
tected, there is always found a gelatinous pulp, covered
with a fine, elaffic membrane, and in this pulp the rami¬
fications of the auditory nerve are loft. It is therefore,
highly probable that \\\zfcat of hearing relides in the
minute nervous fibres that are diftributed through the
pulp, and that this latter is the medium by which founds
are communicated from the percufied air. We may
form a tolerably juft idea of the manner in which this
pulpy fubftance is conneded with the external move¬
ments that are the caufe of found 5 for this quivering
jelly will readily receive the concuflions of the air or
■water that are tranfmitted to it from the vibrations of
fonorous bodies, and communicate them to the nervous
filaments. Thus far only can w-e trace the motion of
found •, but the fteps by which this motion is carried on
till the perception of found is produced in the mind, are
equally unknown to the anatomift and the metaphyfi-
- ^ ciam
Varieties of philofophy of found has already been treated of
found. under Acoustics. It is neceflary here to remark only,
that the qualities of found may be diftinguifhed into
force, depending on the extent of the vibrations of the
body from which the found proceeds; tone, depending
on the velocity of the vibrations*, refonance, arifing
from the intimate compofition of the fonorous body 5
fwiple modulation of voice, and articulations.
S>S The human ear can diftinguifti all thefe different qua-
tiv^phyGo-^68 w*t^1 re^a^on t° one found 5 this diftiuclion is made
logy of w*th vronderful accuracy, by petfons who frequently ex¬
hearing. ercife that faculty, and particularly by profeffional mu-
ficians. The other mammalia exhibit proofs that they
are capable of diftinguifhing the qualities of found which
relate to fpeech, that is to fay, Jimple vocal modulations
and articulations ; for wTe may obferve daily, that they
remember the found and fignxfication of feveral wTords.
Some are ftrongly afFe&ed by certain founds. Acute
tones produce a painful fenfation in dogs, and we alfo
obferve that thefe animals are terrified by violent noifes;
they therefore diftinguifti thefe two properties. Birds
have a feeling, no lefs exquifite, of voice, tone, articula¬
tion, and even refonance, fince they learn to ling with
great correftnefs; and when their vocal organs permit
them, can completely counterfeit the human fpeech,
with all the modifications pradlifed by the individuals
they imitate.
As to cold-blooded animals, it is well known that fe¬
veral of them call each other by certain founds, and that
others, wdiich are incapable of producing founds, can at
Jeafi: underftand them, as carps, which appear when the
noife of a bell indicates to them that they are to be fed, Of
&c.; but we know not w7hat qualities of found they Scniaiion.
diftinguifti, and how far, in this refpedl, the delicacy of" v~
their fenfe of hearing extends *. * Cuvier
, fee Mediciny, Crj1f;An(p'
7 7 vol. 11. iect.
13*
For the morbid aiteftions of hearing
N° 8: .
5. Of Seeing.
97
As we afeend from the finipler to the more complex Seeing*,
fenfes, we find a greater fcope for defeription and ob-
fervation ; but we alfo find our phyfiological difficulties
increafed. The fenfe of touch being the moll fimple of
all the fenfes, requires but a fimple organization, and is
the mo ft widely diffufed; that of vilion, on the other
hand, is the moil; complex, and requires for its mecha-
nifm, a more elaborate fet of organs. There is not, in
the whole animal ftrufture, a more curious and admir¬
able organ than the eye, whether wTe contemplate it in
its moft perfeft ftate in the human body, or in its moft
fimple conformation, as it appears in the horn of a fnail. o8
The anatomy of the human eye has been fufficiently Organs,
deferibed in the article Anatomy, Part I. chap. vi.
feft. 5. } and if our readers defire a fuller account of
this organ, we may refer Them to the elegant work of
Profeffor Soemmering. The ftrifelure of the eye in the
inferior animals is well deferibed in Cuvier’s twelfth
ledfture, and in Blumenbach’s Comparative xlnatomy,
chap. xvi. We fhall extract from the former a deferip¬
tion of the eyes of infers and cruftaceous animals, as
being among the moft; curious and kail known fubjefts
of comparative anatomy.
“ The ftruiflure of the eye of infects is fo very dif¬
ferent from that of other animals, even the mollufca,
that it wTould be difficult to believe it an organ of fight,
had not experiments, purpofely made, demonftrated its
ufe. If we cut out, or cover with opaque matter, the
eye of the dragon-fly, it wrill ftrike againft walls in its
flight. If we cover the compound eyes of the veafp, it
afeends perpendicularly in the air, until it completely
difappears; if we cover its fimple eyes only, it will not
attempt to fly, but will remain perfeftly immoveable.
“ The furface of a compound eye, when viewed by
the microfcope, exhibits an innumerable multitude of
hexagonal facets, (lightly convex, and feparated from one
another by fmall furrows, which frequently contain fine
hairs, more or lefs long.
“ Thefe facets form altogether a hard and elaftlc
membrane, which, when freed of the fubftances that
adhere to it'pofteriorly, is very tranfparent.
“ Each of thefe fmall furfaces may be confidered
either as a cornea, or a cryftalline ; for it is convex ex¬
ternally, and concave internally, but thicker in the mid¬
dle than a( the edges, it is alfo the only tranfparent part
in this lingular eye.
“ Immediately behind this tranfparent membrane
there is an opaque fubftance, wffiich varies greatly as to
colour in different fpecies, and which fometimes forms,
even in' the fame eye, fpots or bands of different colours.
Its confiftence is the fame as that of the pigment of the
choroides; it entirely covers the pofterior part of the
tranfparent facets, without leaving any aperture for the
paffage of the light.
“ Behind this pigment we find feme very (hort while
filaments, in the form of hexagonal prifms, fituated
clofe to each other, like the Hones of a pavement, and
* precifely v
Cuvier's
Lectures,
vol. ii.
99
Immediate
i'eat of vi-
fion proba¬
bly the re¬
tina.
P H Y S I
precifely equal in itumber to the facets of the cornea ;
each penetrates into the hollow part of one of thefe fa¬
cets, and is feparated from it only by the pigment men¬
tioned above. If thefe filaments are nervous, as in my
opinion they appear to be, we may confider each as the
retina of the furface behind which it is placed : but it
will always remain to be explained, how the light can
on this retina, through a coat of opaque pig¬
ment.
“ This multitude of filaments, perpendicular to the
cornea, have behind them a membrane which ferves
them all as a bafe, and which is confequently nearly
parallel to the cornea 5 this membrane is very fine, and
of a blackifh colour, which is not caufed by a pigment,
but extends to its moft intimate texture j we obferve
in it very fine whitifh lines, 'which are tracheae, and
and will produce Hill finer branches, that penetrate be¬
tween the hexagonal filaments, as far as the cornea.
By analogy, we may name this membrane the c/10-
roides.
“ A thin expanfion of the optic nerve is applied to
the pofterior part of the choroides. This is a real ner¬
vous membrane, perfectly fimilar to the retina of red-
blooded animals 5 it appears that the white filaments,
which form the particular retinae of the different ocular
lurfaces, are produftions of this general retina, which
perforates the membrane I have named choroides, by a
multitude of fmall and almoft imperceptible holes.
“ To obtain a diftinft view7 of all thefe parts, it is
neceffary to cut off the head of an infedl that has the
eyes large, and diffedt it pofteriorly j each part will
then be removed in an order the reverfe of that in wdiich
I have defcribed them.
“ In the Cray fillies, in general, the eye is fituated on
a moveable tubercle. The extremity, which is rounded
on every fide, and fometimes elongated into a cone,
when viewed by a glafs, prefents the fame furfaces as
the eyes of infedts. When we cut this tubercle longi¬
tudinally, we obferve that the optic nerve paffes through
it in a cylindrical canal, which occupies the place of its
axis. Arrived at the centre of the concavity of the
eye, it forms a fmall button, which detaches very fine
filaments in every diredfion j at a certain diftance thefe
filaments meet the choroides, wdiich is nearly concentri-
cal with the cornea, and covers the fpherical brulh of
the extremity of the nerve, like a hood. All the di-
flance between the choroides and the cornea is occu¬
pied, as in infedts, by white filaments, clofely arranged
in a perpendicular dirediion to each other, .and which
have the extremity next the cornea alfo coated with a
black pigment.
“ Thefe filaments perforate the choroides, and are
continuations of thofe produced by the button, which
terminates the optic nerve.”
The immediate feat of vifion is ftill in difpute ; but
it appears to be the expanfion of the optic nerve upon
the inner coat of the eye. The other parts of that or¬
gan ferve to colled!, refradl, abforb, and fometimes even
refledl, the rays of light, according as thefe operations
are required for the diftindl vifion of any particular ani¬
mal. Thofe animals that feek for their prey during
O L O G \. Chap. II.
night, have a pupil that is very dilatable, and have Of
very little of that dark fubftance called pigjneutum ni- Senfation.
that lies between the retina and the choroid coat'
in diurnal animals. Thus, the former have their eyes
better adapted to receive and to retain the feeble rays
of light, and thus poffefs a great advantage over the
animals which they purfue, whofe eyes are calculated
for feeing belt in a ftrong light.
The fubjedl of vifion has been fo fully confidered un¬
der Optics, Part I. fedt. j. that it is unneceffary for
us to give any detailed account of it here. We iliall
therefore merely enumerate the principal phenomena. IOo
1. I he rays of light proceeding from luminous bo-Phenomena
dies, are colledted by the cornea j varioufiy refradted byafvifi(>nv
the aqueous, cryftalline, and vitreous humours, till they
meet in a point (in perfect vifion) in the retina, from
which the fenfation conveyed to the brain, excites there
the ideas of light, colour, and other qualities of extreme
objedts, of w’hich the eye is capable of judging.
2* The image ©f the objedt thus pidtured on the reti¬
na, is inverted, though the mind is habituated to perceive
it as if it were eredt.
3. There is a certain point within the eye where the
retina is deficient, and here the luminous rays make no
impreffion.
4. The eye is calculated to fee objedts moft difiindtly
at certain diftances or foci, though thefe diftances vary
confiderably in different fpecies, and different individu¬
als. A perfon of ordinary fight can read a middle-fized
print moft diftindtly at the dittance of about eight inches.
Thofe who require a lefs diftance are near-fighted, or
myopes, and in them the point of divergence of rays is '
before the retina. Thofe who require a greater diftance
are long-fighted, or/rc/Z-p/w ; and in thefe the point of
divergence is behind the retina.
5. In thofe animals that have twro eyes, an image of
a luminous objedt is formed in each, though the mind
is accuftomed to unite both images into one. In ftra-
bifmus or fquinting, the twro eyes not being fimilarly
diredted, do not concur in producing a fingle objedt.
6. Though the images of many objedts are impreffed
on the retina at the fame time, the mind can attend di¬
ftindtly to only one of them.
7. In perfedt vifion, the pupil contracts or dilates ac¬
cording to the greater or lefs quantity of light that is
prefent.
8. When the eye has looked fteadily for fome time
on a circumfcribed fpace, of a particular colour, as a
piece of red paper placed on a w’hite ground, it perceives
a border of a different colour furrounding the original
fpot. This furrounding colour is called the accidental
colour of the former, and differs according to the colour
of the original fpot. In the prefent inftance it is green,
or bluifh-green. The other natural colours are attend¬
ed by the following accidental colours, viz. orange, by
blue, with nearly an equal proportion of indigo; yel¬
low by indigo, with a mixture of violet-, green by
violet, with a mixture of red; BLUE by red, with a
mixture of orange ; indigo by yellow, with a confider-
able mixture of orange ; and VIOLET by green, w ith a
confiderable mixture of Hue (b).
The
(b) Dr Darwin, in his Zoonomia, vol. i. fedt. 2.
4
employs the phenomena of accidental colours to prove that the
fibres
Chap. It.
I* H Y S I
Of The exercife of diftinft vifion depends chiefly on the
Senfation. following circumftances: I. The perfeft tranfparency of
the cornea, and the feveral humours of the eye 5 2. on
Reqaifites tlie juft proportional diftance between the cornea and
for diftindl the cryftalline lens, and on their degree of convexity ;
vifion, on the fenftbility of the retina ; 4. on the degree of
illumination of the viflble objedf 5 5. on the colour of
the pigmentum between the choroid and the retina ;
10* and 6. on the contradiion and dilatation of the pupil.
Adtion of The adtion of light on living beings is not confined
light on the t0 l(-s effedts in producing vifion. It feems to adl on the
/fftem. fyftem in general as a moderate but conftant ftimulus.
When the light of day is vivid, as in bright funfhine,
the body is more adtive, and the mind more vigorous,
than under a cloudy Iky. Thofe climates which are
frequently obfeured by clouds and vapours, are notori-
oully the birthplaces of ferioufnefs and gloom 5 and
Boeotian dulnefs and Englifn melancholy have long be¬
come proverbial 5 while on the contrary, the ferene
brightnefs of an eaftern Iky has been confidered as pe¬
culiarly favourable to the exertions of imagination, and
the flights of fancy. Mr Stuart, a famous pedeftrian
traveller, told Dr Rufti, that during a fummer which
he paired in a high northern latitude, where the fun is
vifible for feveral months together, he enjoyed an un¬
common lhare of health and fpirits, which he attributed
to the long continuance of the light of the fun. In a
ftate of nature moft animals retire to reft when the light
fails, and few people can fleep foundly, unlefs light be
excluded.
The ftimulating effedfs of light are peculiarly evident
on perfons whofe nervous fyftem is unufually fenfible ;
they cannot bear ftrong light, wdiich not only hurts
their eyes, but produces confiderable agitation on their
whole frame. The fame effects are produced on thofe
who have been confined in a dark prifon. The counte¬
nance of thefe unfortunates is pale and fallow. This
latter effeft of the abfence of light is fimilar to what
takes place in vegetables, as we knowT that the colour,
tafte, and fmell of plants depend on their being expofed
ICj to a due degree of light.
Abtence of It has been remarked, that thofe animals which have
light fup- been long confined in a dark fituation, are univerfally
^a* difpofed to grow fat; and this has been found to take
place even in condemned criminals, in whom we wrould
leaft expedft it. This obefity has been attributed chiefly
to the abfence of light. We are difpofed to think that
the abfence of this ftimulus can have no immediate ef-
fe£l, but that the difpofition to obefity depends rather
on the indolence of the confined animals, which is fa¬
voured by the abfence of light.
For an account of the principal morbid affeflions of
vifion, fee Medicine, N° 81.
6. Is there in fame animals a Jixth fenfe ?
104 # _ _ •
Bats fup- From the experiments of Turin and Spallanzani on the
pofed to flight of bats that have been deprived of fight, (fee Mam-
ftnfe 3 MALIA> 38.) it has been fuppofed by fome that the
accuracy with wdiich thefe animals in their flight avoided
the obftacles that w’ere placed in their wray, is owing to
Vol. XVI. Part II.
473
O L O G Y.
fome additional fenre which they poffefs. Others have Of
conceived that the ienfe of hearing which appears to be Senfation
very acute in the fpecies on which thefe experiments “• v
were made, is fufficient to fupply their want of fight.
It is fcarcely poftible to afeertain which of thefe two
opinions is the more probable 5 but the writer of this
article is rather inclined to adopt the latter, from hav¬
ing obferved that when he was walking in an unfre¬
quented ftreet, when it was very dark, he was enabled
to avoid running againft the common flairs that pro¬
jected into the ftreet, from a certain fenfation that he
perceived, when he approached the wrall of the flair,
which he cannot better deferibe than by faying that
the air at thefe points appeared to be unufually ftili.
With refpeft to fenfation in general, we may lay
down the following laws, which are confidered by Du¬
mas as fundamental principles of this function. T, „
1. As activity is an effential charadter of fenfation,LaWS of
this cannot exiit without a certain action of the organs, fenfation.
and muft be proportioned to the degree of attention be¬
llowed on the external objedts, or ideas by which it is
produced.
2. A repetition of the fame fenfations tends to render
the fenfibility lefs acute, and lefs capable of receiving
newr impreflions. By repofe its energy is reftored.
3. As fenfibility cannot be employed on two impref-
fions at the fame time, it muft hold a certain balance
throughout all the organs, and it cannot be acutely ex¬
cited in one part, without being proporponably dimi-
niftied in another. 1
4. Senfibility is a relative faculty, which is not equal¬
ly obedient to all kinds of excitations, but only to thofe
wdiich have fome relation to it in the different parts of
the living body.
5. It is increafcd and accumulated in the diredt pro¬
portion to the defedt or weaknefs of ftimulus.
6. It is not proportioned to the number, arrangement,
or diftribution of the nerves, and its changes of increafe
or diminution are not fufceptible of calculation.
7. It is inconftant, variable in its progrefs, and un-
confinable *. * Dimas,
To thefe wre may add the following fadts refpedling
this funSion and its organs.
1. The nerves which are principally diftributed totheii. p.’151.
organs of the external fenfes, arife from that part of the
fenforium that is within the head.
2. The fenfations produced in any part by ihe con-
tadl of external bodies, are more perfedf, according as
the nerves which terminate in that part arife more im¬
mediately from the common fenforium.
3. When a ligature is faftened on a nerve, the parts
on wdiich the nerve is diftributed are deprived of fenfa¬
tion as far as depends on that nerve.
4. Compreflion of the brain diminilhes general fenfa¬
tion in proportion to its intenfity. Slight compreffion
produces numbnefs.
5. Though fenfation probably takes place only in the
central parts of the fenforium, it is commonly referred
to the extremities of the nerves. Thus, a gouty perfon
who has loft his leg, will fuppofe that he fometimes
3 O feels
fibres of the retina are thrown into contradlion, like thofe of mufcles, and that fome of them act as antagonifts tG
others > as he confiders the accidental as the reverfe of the natural colours.
/-
474
Of feels the pain of the gout in the toe of the amputated
. Senfauon limb#
6. A fympathy takes place between thofe parts which
are fupplied by branches of the fame nerve. Thus, a
violent fcratching of the head often produces fneezing j
powerful odours fnuft'ed at the nofe produce a flow of
tears j the head fympathifes with the ftomach 3 the
mammae with the uterus, &c.
Thefe are all the phenomena refpedting fenfation which
we can at prefent notice 3 we {hall mention others when
we come to confider the relation between this fundtion
io6 and thofe of motion, digeftion, circulation, &c.
Internal What have been called the internal fenfes, as memo-
fenfes be- ry, imagination, and judgement, are rather qualities of
long to me- than operations of the brain 3 and the confi-
‘•P1) 1C“‘ deration of them belongs rather to metaphyfics than
phyflology. To that article, therefore, we refer the
reader ; and we fhall conclude this account of the phe¬
nomena of fenfation with the following comparative view
10^ of that fundtion in the inferior animals.
Compara- In all animals that have nerves, voluntary motions
tive phyfio- and diredt fenfations take place by the fame means as
logy of fen- j[n man< Xhe differences in their motions depend partly
on the intrinfic mobility of their fibres, and partly on
the difpofition of their mufcles, and the parts to which
they are attached.
The differences in their fenfations depend on the num¬
ber of their fenfes, and the perfedlion of the organs be¬
longing to each fenfe. The animals that approach near-
efl to man have their fenfes equal in number to his. In
certain fpecies, fome of thefe fenfes are even more per-
fedt in the ftrudture of their organs, and fufceptible of
more lively and delicate impreflions than ours ; on the
contrary, in proportion as animals are removed from us,
the number of their fenfes and the perfedlion of certain
organs are diminifhed 3 but perhaps fome animals, at the
fame time, polfefs fenfes of which we can form no
idea.
We know not whether there are diflerences in the in¬
trinfic fenfibility of the nervous fyflem of different ani¬
mals, i. e. whether an equal impreflion made on an or¬
gan equally perfedt, wrould afledl every animal with the
fame force.
The animals next in order to man have, like him,
fpontaneous, or what we call internal, fenfations. Images
are excited in them at times, when they receive no im¬
mediate impreflxon from external objedls. Thus, dogs
and parrots dream. We are not certain, indeed, that
the more inferior animals experience fimilar fenfations.
The paflions produce effedls in animals fimilar to thofe
which they excite in man. Love is manifefted in the
fame manner in all clafles 3 fear occafions a difcharge
of excrements in quadrupeds and birds 3 it makes them
tremble, and even renders infedts immoveable 3 but the
other animals afford fewer examples of thefe kind of
phenomena than man, becaufe they are not mailers of
their imagination, cannot diredl it towards certain ob¬
jedls, and create for themfelves fadlitious paflions. We
are even ignorant whether their imaginations can, like
ours, be wrought up to fuch a pitch as to make them
experience emotions of anger, defire, or fear, from Am¬
ple ideas or Ample recolledlions; and whether the real
prefence of the objedls which caufe thefe paflions, is not
always neceffary to excite them in the inferior animals 3
we know, however, that thofe which approach nearelt
Chap. IX.
to us, the mammalia and the birds, have their forrows. Of
The afflidlion they feel on the abfence or lofs of a com- Senfation.
panion, friend, or benefadlor, is manifefted by evident
figns, in the fame manner as they teftify their attach¬
ment without any temporary inducement.
The fame animals exhibit frequent proofs of a very
perfedl memory 3 fome even appear to poffefs a certain
degree of judgement. Eut does any thing fimilar exiil
in the inferior claffes, and particularly in the loweft ?
Of this we ftiall probably remain always ignorant.
With fo much refemblance in the ftrudlure of the
nervous fyftem, in its mode of adtion, and in the num¬
ber and ftrudlure of the principal external organs, why
is there fo vaft a difference, as to the total refult, be¬
tween man and the moft perfedl animal ?
Is this owing to a more accurate proportion in the re¬
lative perfedlion of the external organs, fo that one does
not fo much furpafs another ? Or has the internal organ,
in which are performed all the intermediate operations
between the fenfation received and the movement exe¬
cuted, that is to lay, the organ of perception, memory
and judgement, greater differences than wre have yet
obferved ? Or, finally, is the fubftance by which thefe
proceffes are effedled of a different nature ? Thefe, how¬
ever, are not anatomical queftions.
The fympathies or effedls refulting from the connec- * Culler'
tions of nerves with each other, and the influence of the LeOures *
nerves on vegetative fundlions, are fubjedl to the fame vol. ii.
laws in man and the other animals *. I08
The theory of fenfation is perhaps more imperfedl Theory of
than that of any other fundtion. On this fubjedl we can fenfatio1'-
derive little light from the ftrudlure of the brain and
nerves, accurately as this has been examined. Anatomy
has taught us, that the principal part of thefe organs
confifts of very delicate fibres, intermixed with a medul¬
lary pulp, and incafed in membranes 3 and that they are
furnilhed with a great proportion of blood-veffels 3 but
whether the feat of fenfation refides in the fibrous or me¬
dullary part, vre cannot afcertain.
It was formerly the opinion, that the nervous power Vibration,
was propagated between the brain and the external or¬
gans, by vibrations of the nerves 3 but as the ftrudlure
of thefe chords, and their connedlion with furrounding
parts, muft wholly difqualify them for fuch vibrations,
this theory has long been abandoned. IIO
Another hypothefis that has been very generally re-Nervous
ceived is, that the nervous fibres are the conductors of^u^
a very fubtile fluid, called the nervous fluid, the motions
of which are the caufe of fenfation. This was the opi¬
nion of Dr Haller, (Ffiy? Lines, chap, x.) and was ftre-
nuoufly maintained by Dr Cullen. We {hall prefent our
readers with the following modification of it, as given
by an able difciple of Cullen.
“ It is probable, (fays this writer), that in each ner¬
vous fibril, an elaftic fluid is inherent, forming, from the
moment of animation, a part of it 3 differing, however,
according to the ftate of the conftitution, in power, mo¬
bility, and, perhaps, in other qualities. Of this fluid
the nerves are condudlors, and are furrounded in their
courfe by non-condudling membranes, while the fame
membrane lines every part of the brain, and is carried
into the deepeft cavities, guarding with particular atten¬
tion the flighteft aperture. In this view fanguiferous
veffels are chiefly ufeful in nouriftiing this medullary fub¬
ftance, and they appear to be neceffary alfo in adapting
the
PHYSIOLOGY.
Chap. II.
Of the nerves to their office •, for, when the circulation is
[,Senfation greatly increafed, the fenfibility is more acute *, and
' » when it languifties, or is deftroyed, the nervous energy
foon (hares the fame fate.
“ This fluid muft neceffarily be an elaftic one ; and
impreffions are apparently conveyed through it by vi¬
brations. It does not follow from hence, that the nerves
vibrate like mufcular cords j or that, in every the flight-
eft motion, a portion is conveyed from the brain. The
elafticity of the fluid is proved from the momentary con¬
tinuance of the impreflion after the caufe is removed;
and vibration is a term employed in many branches of
philofophy as a means of communicating motion, with¬
out any diftintft application. If we touch an objeft with
a flick, or with a metallic rod, we perceive through it
the impreflion, and, in a general way, the nature of the
fubftance. The impreflion muft be conveyed by fome-
thing j and whatever that fomething is, it may as well
convey impreffions through the nerves as through the
rod. But through the nerves only can it affetft the
brain, and produce an idea, or fome change in the
brain, or its fluid connefled with the nature of the ob-
jeift, and which conveys to the mind fome peculiar and
* New difcriminated impreffion which it afterwards retains
London A third hypothefis, jvhich is at prefent very falhion-
Meduai able? iS) that fenfation is produced by a change in the
vol. lT7' fubftance of the brain and nerves. M. Cuvier is an ad-
398. vocate for this do&rine, which he illuftrates in the fol¬
lowing manner.
The nervous fyftem is fufceptible of two kinds of ac¬
tion *, one which is confined to our fenfitive faculty, and
another which affedls our vital and vegetative funftions
only. External fenfations are produced by the impref¬
fions of external bodies, on our fenfes $ internal fenfa¬
tions, by changes which take place, in the ftate of the
internal parts of the body, to which the nerves are di-
ftributed ; and fpontaneous fenfations are caufed by a
change in the nerves, or in the brain itfelf, without any
external excitement.
Thefe circumftances, added to the phenomena arifing
from the cutting or tying of nerves, {how, that fenfation
does not refide in the external organs, but nearly in the
centre of the nervous fyftem, and that the external or¬
gans ferve only to receive the action of the external bo¬
dies, and to convey it to the nerves, by which it is propa¬
gated to a greater diftance. They alfo demonftrate,
that this propagation is not produced by any matter or
concuffion, but by a change in the ftate of the nervous
fubftance. This change may arife from internal caufes,
or it may be produced by external caufes, different from
thofe which ufually occafion it. The nerves are not
merely paffive agents, nor the conductors or refervoirs of
any particular matter *, but it appears, that the fubftance
which produces fenfation, is liable to be confumed, or
to lofe its aftivity by exertion.
There are phenomena which {hew that the general
fufceptibility of the nerves, for receiving fenfations, may
vary in confequence of caufes external to the nerves
themfelves, and which can operate only by altering
their fubftance. Certain medicines weaken or revive
that fufceptibility ;—inflammation frequently increafes it
to an exceffive degree. Does this take place in confe-
quenCe of an increafed fecretion of the nervous matter ?
The moft remarkable change that occurs in the fufcepti-
hility of ne.rves, is fleep. It is not unnatural to fupppfc
475
that this change may be occafioned by the temporary Of
lofs of the fubftance which is effentially fenfitive. But Sen^riorl‘.
how does it happen that fleep depends, in a certain de- ""
gree, on the will ? Why do w-e awake fuddenly, or
from caufes which do not appear calculated to reftore
that fubftance ? Wliy does cold produce fleep ? From
thefe obfervations, may it not rather be fuppofed that
this ftate is the effeft of a change in the chemical nature
of the nervous fubftance ?
But whether the fubftance contained in the nerves is
exhaufted by fenfations, or whether it merely undergoes
an alteration in its chemical compofition, and becomes,
as it w'ere, neutralized, it muft remain in the nerve
throughout the whole of its courfe, and leave it only at
one of its extremities. It does not, however, refemble
the blood in the veffels, either as to the manner in which
it is retained, or in which it moves in the nerve. There
is no evidence of the nerves being tubular. No pheno¬
mena indicate that any matter efcapes from them when
they are divided. Befides, what veffels could have pa-
rietes fufficiently compadl to retain fo fubtile a fluid as
that of the nerves muft be. It is far more probable that it
is retained in the nerves, in the fame manner as the elec¬
tric matter is in ele&ric bodies, by communication and
infulation $ and that the nervous fyftem is its only con-
duftor, wrhile all the other parts of the animal body are,
with refpeft to it, cohibent fubftances *. * Cuvier's
The theory of fenforialpower, brought forward by Le£tures,
Dr Darwin, has already been noticed. vo1, “•
Chap. III. Of Irritability.
1. When any part of a living animal body that con-General
tains mufcular fibres, as a part of its compofition, is phenomena
touched with a {harp inftrument, with a hot iron, orof hriubili-
with a corrofive liquor j or when a {hock of eleftricityty-
or galvanifm is made to pafs through it, a contradlion
takes place in the part, and this contraftion is difconti-
nued wdien the ftimulus is removed, but is renewed on
repeating the application.
2. The fame contractions take place in certain parts
of a living animal body, from an exertion of the will.
3. Many parts in which the prefence of mufcular
fibres has not been afcertained, poffefs the fame capacity
of being excited to motion by ftimuli. Such are the
ureters, the biliary duCts, the fmall blood-veffels, and
probably the lymphatics; all of w-hich, though not evi¬
dently mufcular, have a fibrous ftruCture.
4. Some parts of the living animal body which ap¬
pear rather nervous than mufcular, poffefs a contra&ile
power, as the retina.
5. When the nerves wffiich form a communication be¬
tween a contraftile part and the brain, in the higher or¬
ders of animals, are divided or compreffed, thofe parts
which before contracted in obedience to the will, lofe
this power j but,
6. Thefe parts, as well as every mufcular part, ftill
contract on the application of ftimuli, particularly elec¬
tricity and galvanifm.
7. Such parts of an animal body as have mufcular
fibres, are thrown into contraction on the application of
ftimuli, for fome time after having been feparated from
the living body, provided that nervous filaments remain
conneCted with the mufcular fibres.
8. It has been found, that the fibrine of. the blood is
3 0a fufceptible
PHYSIOLOGY*
112
Definition
ef irritabili¬
ty
. TI3
Different
applications
of this
term.
P II Y S I
ful'ceptible of contraction on the application of the gal¬
vanic ftimulus, after having been feparated from the liv¬
ing body.
9. In fome animals in which a nervous fyftem has
not been detedled, as polypes, this contradtile power
feems to pervade every part of the animal.
10. Plants, in a greater or lefs degree, poffefs the
power of moving on the application of Itimuli *, and in
fome fpecies this motion is very remarkable. See
N° 57.
The above are fome of the principal phenomena
which take place in organized beings with refpedt to
irritability. They are fo analogous, that wTe may attri¬
bute tlrem to the fame caufe or the fame vital power.
This fufceptibilty of being thrown into contraction on
the application of Itimuli is called irritability j and it is
poffelfed in a greater or lefs degree by every organized
being with which we are acquainted.
We have refiricted the term irritability to denote the
fufceptibility of the fibrous ItruCture to contraction on
the application of ftimuli ; but it is proper to remark
that this term has not always been ufed in the fame
fenfe.
Irritability has long been employed in medicine, as
in common language, in reference to the paflions, efpe-
cially that of anger ; and this appears to have been the
original meaning of the term.
Malta fero ut placem genus irritahile vatuin. Hor.
It is perhaps ftill more common to apply it to a mor¬
bid fenfibility of the fyftem j and we fpeak of a perfon
being of a very irritable habit, or poffefling a great de¬
gree of irritability, when we mean to fay that he pofieffes
a more than ordinary {hare of fenfibility, liable to a
more keen fenfation of the fame impreflions.
“ Or are your nerves too irritably ftrung.”
Armstrong.
Even the accurate Dr Whytt, to whom the proper
diftinCtion between irritability and fenfibility mult have
been familiar, and by whom it is in general ftriCtly re¬
garded, fometimes falls into this inaccuracy. He fpeaks,
in his work on nervous difeafes, of “ a delicate or eafily
irritable nervous fyltem.” In fad, this confufion of irri¬
tability with fenfibility, appears to be a Humbling block
to Hnofl pbyfiological writers. We fhall prefently in¬
quire how far they are independent of each other.
The term irritability, in its moft received accepta¬
tion, as a property of the mufcular fibre, feems to have
been firft employed by Gliffon, about the middle of the
17th century. Ide diftinguiflies two kinds of irritability,
^Gliffon Pr’maiT or direft, and fecondary or fympathetic *.
de Ventti- Haller was, however, the firit, who treated of irritabi-
culo et In- lity with any degree of accuracy. He confines it to the
lejlims. mufcular fibre 5 though at the fame time he will not al¬
low it to many parts, the mufcularity of which has ne¬
ver been queftioned, and which, fince his time, have,
by decifive experiments, been proved to poffefs a confi-
derable degree of contraClile power. He -completely di-
O L O G Y. Chap. III.
ftinguifhes irritability from fenfibility, with which he Of
will have it to be totally unconnected ; and he attempts Irritability,
to make a diftinCtion between the irritability of the liv- y *
ing, and that of the dead fibre f. | Haller's
Dr Whytt, whofe controverfy with Haller refpeCring Firjl Lines
the nature of irritability and fenfiblity is famous in the °f Phyfl°-
annals of medical warfare, admits three kinds of irrita-
bility : 1. That power of alternate contraction and dila¬
tation which is peculiar to thofe organs we call mufclesj
2. That uniform contraction which takes place in the
dartos (one of the coats of the fcrotum) and the pores
of the fkin j and, 3. That rednefs and inflammation:
which is excited in every fenfible part of the body, as
often as acrid things are applied to it j although this laffc
is allowed by him to be only an effeCt of the firft kind
of irritability taking place in the fmall veffels of the
part J. Thus, he reduces the three kinds to two, and f Whytt'r
we may perhaps confider his fecond kind only as a mo- Phyfiologi-
dification of the firft. Ejfcys,
Among thofe who feem to have a fufficiently juft
idea of the nature of irritability, the word itfelf is not
unfrequently mifapplied. Thus, Vicq d’Azyr ||, and d Encyclop.
Dumas $, in enumerating the functions of the animal
body, called thofe of motion and fenfation, irritability Comparee.
and fenfibility. Thefe latter are powers or capacities of ^ principes
living beings, and as fuch fliould be diftinguifhed from de Phyfio-
the functions that depend on them. logic, tom.
In confidering the phenomena of irritability, it is ne-u
ceffary to take notice of the feveral kinds of Itimuli . Ir4
which excite it. Thefe have been reduced by Cuvier to
five orders, viz. volition ; external aclions operating on tability.
nerves; external actions operating on the Jibre itfelf j
mixed aBions operating on both the nerves and Jibres1
and certain difeafes or violent emotions. ir^
When the animal body is in a Hate of health, and Volition,
awake, the will exercifes a prompt and conftant influ¬
ence over the greater part of the mufcles, which, on
that account,, are denominated voluntary mufcles. A
fmall number of mufcles, viz. thofe which produce the
internal movements neceffary to life, and which cannot
be interrupted, fucb as the heart and the alimentary ca¬
nal, are not fubjeCI to the will. It muff be obferved,
however, that fome of the mufcles, that in man and
moft other animals are involuntary, are fubjeCt to the
will in others. This is the cafe with the ftomach in ru-
rpinating animals, the movements of which may be ex¬
erted at pleafure in two different directions. In fome
mufcles, as in thofe of refpiration, there feems to be a
mixed aCtion with refpeCt to the will, as this faculty can
interrupt their motion for a time, though, in general,
this is continued from habit, without the will, or even
confcioufnefs of the animal. Thofe mufcles that are ab-
folutely involuntary, are continually excited by an
extraneous irritating caufe j for the blood which is
brought to the heart on every dilatation, determines that
organ to contraction, and the alimentary canal is affeCt-
ed in the fame manner by its contents. It feems, there¬
fore, that the will is not effential to the aCtion of thefe
mufcles, and that it cannot interrupt their motion (c).
(c) There are faCts which fhew that the will has often confiderable influence even on mufcles that are uniyer-
fijly ftyled involuntary. The abbe Fontana, when making experiments with wheel polypes, was led to believe
that the heart, in thefe animalcules, is a voluntary mufcle, and from this belief he learned? in fome degree, to ac-
oelerat®
Chap
HI. PHYSIOLOGY.
Of A mufcle laid bare, and expofed to an irritating caufe, there have been feveral opinions
116
Nervous
energy.
117
External
ttunuli.
118
Calvaniixn.
Irritability yyjjj contraft itfelf, even in the living fubject, without
being influenced by the will. It fhould feem, therefore,
that though the mufcles which we call voluntary, are
ufually put in motion by the will, they may yet be ex¬
cited to aftion in oppofition to that faculty.
The will itfelf feems to a£f only through the medium
of the nerves ; and it is found that thofe nerves which
fupply the voluntary mufcles, are generally the largeih
The external ftimuli that a£l on the mufcular fibre
through the medium of the nerves, and on the fibre it¬
felf, are chiefly of a mechanical and chemical nature, as
concuflions, punftures, lacerations, all of which are ca¬
pable of producing convulfive motions in all the mufcu¬
lar parts to which the nerves extend.
One of the moll: remarkable of thefe ftimuli is the
galvanic influence. It is well known that the experi¬
ments by which this influence is made to aft on the
mufcular fibre, conlilt in eftablilhing between a mufcle
and the trunk of the nerves which extend to it, an ex¬
ternal communication with one, or a feries of lubltances
placed clofc to each other. Metals are not the only
means that may be employed in this operation ; and in
general, the conduftors are not the lame as thofe of elec¬
tricity. Experiments have fometimes been fuccefsfully
performed, wdien an interval wras left in the feries of ex-
citators : this circumlfance, in the opinion of Cuvier,
proves the exiflence of an atmofphere.
The moment the contaft takes place, the mufcle fuf-
fers violent convulfions. Thefe experiments fucceed on
the living body, or animals recently dead, and even
on parts feparated from the body, precifely in the man¬
ner of thofe which Haller accounts for on the principle
of irritability. Neither pointed inftruments nor acrid
liquors are neceffary j and the galvanic experiments
even fucceed w’hen thefe means have failed.
Diltenfion has been obferved to have a powerful ef-
feft in exciting irritability.
Violent paflions may, to a certain degree, be confi-
dered as the afts of the will ftrongly excited. Thefe,
in fome cafes, have an influence even on the involuntary
mufcles ; for it is no unufual thing for palpitation of
the heart, and fometimes even a fufpenfion of its mo¬
tion, to be the confequence of ftrong paflions. Thefe
aftions, however, are to be prevented by moderating the
excefs of fenfibility by which they are occafioned. Even
in nervous difeafes, which appear to be the leall con-
nefted with thofe paflions wdrofe influence is more im¬
mediately felt, the will is often capable of preventing
or retarding the approach of nervous fymptoms, when
the patient is determined to refill the paroxyfm.
From what has been faid, it appears that, in the fu-
perior claffes of animals, all the orders of ftimuli, either
aft through the medium of the nerves, or that they are
capable of being modified or controuled by the will, the
exertion of wdrich depends on nervous influence.
Caufe of xr- With refpeft to the immediate caufe of irritability,
stability.
M9
Diftenfion.
120
Violent
pafiion?.
- ^ 477
One of thofe which Of
has been moft generally received is, that irritability Irritability.
Is intimately connefted with fenfibility ; or, that it is v
an immediate efteft of the nervous power. This was
the opinion of Whytt and Cullen, the former of
whom endeavours to prove it by the following argu¬
ments. 122
1. We almoft always obferve the irritability of tbe Whytt’s ar-«-
mufcular organs of tbe human body to bear a proper- gnments
tion to their fenfibility. Thus, children, and people nefvous
delicate nerves and very quick feelings, are moil fub- influence,
left to convulfive and Ipafmodic difeafes, while on the
other hand old people, and thofe of lefi delicate fenfi¬
bility, have a mufeuiar lyftem that is not fo irri¬
table.
2. Whatever increafes the fenfibility of the mufcles,
alfo increafes their irritability.
3. Whatever leffens or deftroys the fenfibility of tbe
mufcles, alfo leffens or deftroys their irritability or
power of motion.
4. That the motions of irritated mufcles are owing to
the fenfation excited by the ftimulus applied to them,
Dr Whytt thinks highly probable, if it be confidered
that we are in faft coufcious of many involuntary mo¬
tions in our own bodies, proceeding from a particular
fenfation, either in the organs moved, or in the neigh¬
bouring parts. * r * Phyftofr*-
Dr Cullen was fo fully convinced of the neceflity oigical Ef-
nervous influence to produce mufcular contraftion, that^y-f, Effay
he confidered the mufcular fibre to be only a conti-11*
nuation of the nervous fibre. See Medicine, N° 73. 123
Haller, as we have faid, firenuoufly maintained, that Hall1^sof
irritability was quite independent of the nerves, and was°£”^°“
an inherent power or vis injita of the mufcular fibre.^/^.
Indeed there are feveral circumftances which would in¬
duce ns to believe that irritability is at leaft, in fome
cafes, independent of nervous influence. We have feen
(N° 111.) that it takes place in thofe animals in which
there is no appearance of nerves ; and that it is very re¬
markable in fome fpecies of vegetables, in which none
but the moft fanciful phyfiologifts have dreamed of
finding a nervous fyftem. Nay, it appears that the
fibrine of the blood, which we can fcarcely fuppofe to
be affefted by the nervous power, when taken out of the
body, is ftill fufceptible of imitation. r2^
From, a comparifon of all thefe circumftances, we General
muft either conclude, that the irritability of living muf- conclufion
cles, and of the fuperior animals, is different from that of
the fibrine, of polypes and plants j or, if we admit thatJ~
nervous influence is effential to irritability, we muft al¬
fo allowr that this influence defeends to the latter clafs
of organized bodies. 125
Before we quit the fubjeft of irritability, we muft no- Chemical
tice the chemical hypothefes that have been lately pro- ^tabili
pofed, to explain the immediate caufe of this faculty. ty<
The firft of thefe is that of Girtanner, who con- 126
fidered oxygen as the principle of irritability. The Girtanner’s
arguments °P’I^ons*
celerate and retard the motion of his own heart. We have even heard of a perfon who had fuch a command over
both heart and lungs, that he could, at pleafure, arreft the motion of both, and affume all the appearance of a
lifelefs corpfe. Many of thofe mufcles, which, in ordinary fubjefts, are not obedient to the will, as thofe o£-
the nofe and external ear, may, however, become fo by habit or patient afiiduity in cultivating their aftion,
47$ P H Y S I
Of arguments on which he founded this opinion are the fol-
Irritability. lowing.
v ' i. The irritability of organized bodies is always in a
direft ratio to the quantity of oxygen they contain.
2. Every thing that augments the quantity of oxygen
in organized bodies augments at the fame time their ir¬
ritability.
3. Every thing that dimini(hes the quantity of oxy¬
gen diminilhes likewife their irritability.
He diftinguilhes the organized fibre by three differ¬
ent ftates :
1. A ftate of health, or the tone of the fibre, in which
the oxygen exifts in its proper quantity.
2. A ftate of accumulation, in which the fibre is over¬
charged with the oxygen or irritable principle.
3. A ftate of exhaujlion, in which the fibre is more or
lefs deprived of it.
He likewife arranges the fubftances, that are capable
of coming into contact with the irritable fibre, into
three claffes.
The firft comprehends thofe fubftances that have the
fame degree of affinity for the irritable principle or oxy¬
gen, as the organized fibre itfelf $ hence the fubftances
produce no effedl upon it.
The fecond comprehends thofe fubftances that have
a lefs degree of affinity for o»xygen than the organized fi¬
bre has : hence thefe, when they come into contaft with
it, furcharge it with oxygen, and produce a ftate of ac¬
cumulation. They are called negative ftimuli.
The third comprehends fubftances for which oxygen
has a greater affinity than it has for the organized fi¬
bre. Thefe, therefore, deprive the fibre of its oxygen,
and produce a ftate of exhauftion. They are called po-
fitive ftimuli.
By way of anfwer to this fanciful do&rine, we may
obferve, that if oxygen were fo effential to irritability
as is fuppofed in Girtanner’s pofitions, thofe animals
which refpire moft oxygen ffiould poffefs moft irritabili¬
ty, and thofe which are capable of living for a long time
in deoxygenated air, ffiould have their irritability
very low. Now, the reverfe of this is found to take
place. The mufcular fibres . birds which refpire more
' Johnforit oxygen than moft other animals, poffefs but little irri-
' tability, while reptiles and worms, which can live for a
long time without oxygen, are univerfally and ftrongly
irritable *.
The other opinion is that of Humboldt, who confi-
ders the galvanic fluid as the fource of nervous power,
and the primary caufe of irritability. He lays down
three principles as neceffary to excite irritability j viz.
1. Oxygen, which forms combinations with different
acidifiable bafes. 2. The acidifiable bafes (carbone,
hydrogen, azote, and phofphorus,) of the fibre, with
which the oxygen may combine. And 3. The galvanic
fluid.
The galvanic fluid produces, according to Humboldt,
the fame effeft in the animal economy, as the eleftric
fluid in the mixture of azote and oxygen. It is this gal¬
vanic fluid that, being conveyed by the nerves, brings
about the combinations of the oxygen with the different
acidifiable bafes of the fibres 5 but when the nerve of a
part is tied, it prevents the fluid from paffing, wffiich ex¬
plains the reafon of the irritability being deftroyed.
The oxygen neceffary fca* thefe unions is carried by
the arterial blood in the courfe of circulation f and the
4
Animal
Chemijlry,
vol. iii. .
127
Hypothefis
of Hum¬
boldt.
O L O G Y. Chap. III.
acidifiable bafes, which are to unite with it, are found to Of
be already prefent in the fibre. Irritability^
He found that every thing that augments too much v—
the quantity of the acidifiable bafes diminiffies the irri¬
tability 5 and that every thing that increafes too much
the quantity of oxygen, likewife diminiffies it j and he
thinks it very probable, that the fame takes place with
refpeft to the proportion of the galvanic fluid.
It is therefore only in a juft equilibrium of thefe prin¬
ciples that the neceffary irritability of the parts confifts.
Upon thefe principles this phUofopher thus explains
the production of mufcular motion. “ In a ftate of re-
pofe, the nerve being inferted in the mufcles, the gal¬
vanic fluid is put into equilibrium in organs that touch
each other. The fpontaneous motion is made by a fur-
charge of galvanic fluid into the nerve. It appears
that the inftant we wiffi to make a motion, the gal¬
vanic fluid produced in the brain, is carried en majfe to¬
wards the part that ought to move, and furcharges the
nervous fibres. A difcharge from the nerve is then
made into the mufcles. The particles of thefe laft, ani¬
mated by increafed affinities, approach each other, vxA*John/on't
it is this that conftitutes the phenomena of mufcular mo- Animal
tion Cbemijlry,
Dumas lays down the following fundamental laws^ ^ p*
refpeCling animal irritability. ri8
1. The effential charafteriftic of irritability confifts Laws of ir»
in a feries of contractions and dilatations, determined r‘tab*^ty
either by the impreffion of an external ftimulus, or by the ^
Ample exertion of the will.
2. Irritability is independent of the aCtion of the
nerves} and though generally diffufed throughout the
animal organization, it belongs rather to the mufcular
fibre than to any other ftruCture. Its aCtion is in pro¬
portion to the number of fibres upon which the irritating
caufes can exert their influence.
3. Irritability is a relative faculty which is not indif-
criminately obedient to every fpecies'of excitation, but
only to thofe which have fome relation to it in the dif¬
ferent parts of the living body.
4. There belongs to each organ a fpecific irritability
which requires a peculiar ftimulus, accommodated to
its nature, and to the kind of functions which it ex-
ercifes.
5. Irritability has certain viciffitudes of diminution
and increafe, which vary in the different fpecies of ani¬
mals, in the different organs of the fame animals, and
under the different circumftances that fucceffively occur
in the life of an individual.
6. Irritability is developed with moft energy at the
moment of death, and immediately after this has taken
place.
7. It is multiplied and revived in proportion as the
organ which has loft it is divided into a greater number
of pieces.
8. It diffufes itfelf in each part with a velocity pro¬
portioned to the aftivity, number, and duration, of the
irritations by which it is excited.
9. There exift mutual relations with refpeCt to influ¬
ence between fenfibility and irritability, though each of
them is effentially diftinCt from the other.
10. The exercife of this faculty fuppofes in the organs
a moderate degree of cohefion, above or below which * Principei
the aCtion of this force is enfeebled, obftruCted, or op- de Pbyjio-
pofed - TZT
Chap. P'53'
Chap. IV.
Of Animal
. Motion. ^ Chap. IV. Of Animal Motion.
Organs of The organs of motion vary confiderably in their na-
motion. ture and connection in the different claffes of animals.
In fome tribes, as in the animalcules and polypes, no
ditfind organs can be obferved. In all above thefe,
however, there are evident mufcular fibres, and in many
there are hard parts or ftrong membranes, which ferve
as points of attachment and fulcra of motion to thefe
fibres. The mufcular fibres are to be confidered as the
eiTential moving organs, -while the parts to which they
are attached are merely the paffive fundions of this or¬
gan. It would be out of place here to enter on a com¬
parative account of the organs of motion 5 and there is the
lefs occafion for it, as they have been more or lefs fully
defcribed in the former part of the work. The bones, liga¬
ments, mufcles, and tendons, with their appendages, as
they appear in man, have been amply defcribed in the
firft and fecond chapters of the Firft Part of Anatomy j
and thofe of other animals have been briefly noticed in
the Second Part of that article. Such of our readers as
wifh for a more particular account, may confult Cuvier’s
Ledures vol. i. or Blumenbach’s Comparative Anato-
my, chap. 1, 2, 3, 4, 5, and 22.
Principles Many of the phenomena of mufcular motion, as they
of mufcular take place in man, have alfo been related under Anato-
adion. my, N° 85 and 86. We ftiall here therefore only enu¬
merate and briefly illuftrate thefe phenomena, and fhall
then proceed to confider a molt interefting part of the
phyfiology of motion, the progreflion of different ani¬
mals.
Dr Barclay, in his late excellent work on the muf¬
cular motions of the human body, has confidered the
general fubjed of mufcular adion under the following
heads, which may be confidered as fundamental prin¬
ciples.
1. Flefhy fibres that are continued into tendon by a
ftraight line, fhorten the mufcle which they compofe, in
the fame degree in which they fhorten themfelves j thofe
fibres which enter the tendon obliquely, fhorten it more,
and ftill more in proportion to their degree of contrac¬
tion, as they deviate more from the line of the tendon,
and approach nearer to the perpendicular, in which laft
diredion they would fhorten the mufcle mofl with the
leaf! contradion.
This may be illuftrated in the following manner.
p»iate Let AB (fig. 1.) reprefent a tendon, and CD a flefhy
Ccccxvn. fibre j and let us fuppofe that AB is the diameter, and
1. CD the radius of the fame circle ADB. It is evident
that if the fibre CD flrould contrad fo as to bring the
point C of the tendon to the point G in the ftraight
line, the extremities of the tendon A, B, (which are
fuppofed to be moveable) would come refpedively to E
and F; and the fituation of the tendon itfelf would be
reprefented by the angle EGF. If the fibre could be
fuppofed to contrad fo as to bring the point C to D, the
two parts of the tendon CA and CB, would come in
contad. If, on the other hand the fibre CH, which
enters the tendon obliquely, were to contrad to H, fo
, 479
as to bring the point C to H, the point A would be ©f Animal
drawn but a little beyond the middle point C, fo that, Mot1011- a
although this latter fibre is contraded to as great an
extent as the former, it has not brought the extremities
of the tendon fo near together.
2. When two fibres enter a tendon on oppofite fides
and contrad at the fame time, they will draw the ten¬
don in the diagonal, and the more nearly the angles
which they form with the tendon approach to right
angles, the more will the length of the mufcle be fliort-
ened in proportion to the degree of contradion of the
fibres. 1
Let the fibres BC, BD, BE, BF, BG, (fig. 2.) be ^
flefhy fibres, inferted into the tendon AB, at the point
B, and let us fuppofe that all thefe fibres co-operate in
bringing the point B to the point G, in the ftrarght
line BG. Now the ftraight fibre BG will be fo much
fhortened when B comes to G, as to be obliterated,
while the oblique fibres EB and FB will be fhortened
only to E o and F £, and the more oblique fibres CB
and DB will remain of the length of C c and D d.
3. All mufcles that are inferted into bones, are there¬
by furnifhed with levers, and as in the adion of all
levers there are alfb a fulcrum, a power, and a refift-
ance, thefe in different cafes will be differently fituated
with refped to one another.
a. In the motions of the head backward and forward
on the atlas, the fulcrum is fituated between the power
and the refiftance; or the lever is of what is called in
mechanics, the firft kind. See Mechanics, N° 33.
b. When the tibia refts upon the aftragalus, and the
heel is raifed by the mufcles of the calf of the leg ading
on the tendo achillis, the refiftance (which in this cafe
is the preflure of the tibia) is fituated between the
power and the fulcrum, which are here refpedively at
the heel and at the toes j or the lever is of the fecond
kind.
c. In railing a weight at the palm of the hand, and
bending the arm at the joint of the elbow, the power
of adion in this joint is fituated between the refiftance
and the fulcrum, which are here refpedively at the
palm of the hand and the diftal extremity of the hu¬
merus (d), or the lever is of the third kind.
The ihortnefs of the lever, and the confequently great
force of the mufcular power required to overcome the
refiftance in this laft cafe, may be thus illuftrated. Let
AB (fig. 3.) reprefent the radius articulated at B with p;„,
the humerus BC ; let DFE reprefent the biceps flexor
mufcle running along the humerus, and attached to the
radius at E j and fuppofe a weight W hung to the dif¬
tal extremity A of the radius. Now, BH will repre¬
fent the lever of refiftance, and BG perpendicular to it.
the lever of the mufcle, which is in this cafe extremely
fhort.
4. As, other things being equal, all mufcles pro¬
duce a greater extent of motion by a lefs proportion¬
al degree of contradion, and confequently a lefs propor¬
tional change in their fibres, than if they were fhorter ;
thofe mufcles which follow a dired courfe are feldom
attached at the neareft points of the two bones with
which
PHYSIOLOGY.
(d) In Dr Barclay’s nomenclature, that extremity of a bone which is towards the trunk is called proximal^ andi
that extremity which looks from the trunk is called diflal.
Motion.
Tig. 4.
480 P H Y S I
Of Animal wlilcli they are corme&ed. Hence, befide the advan¬
tages already mentioned, relations are thus formed be¬
tween parts at a diftance, and the mutual dependence of
the fundlions and their organs is extended and ilrength-
ened. On the contrary, thofe mufcles that are not ex¬
tended along the furface of the bones to which they are
attached, are obferved to follow an oblique direftion, by
which they acquire not only contradlibility and length,
but at the fame time a fhorter lever than if they had
been inferted at the fame place with a lefs obliquity.
5. Of mufcles attached to ribs that are parallel,
equally moveable, and at right angles to the vertebral
column, thofe that follow a diredfc courfe from one to
the other, will a£l on each by equal levers, and make
them approach with the fame velocity ; while thofe that
obferve an oblique courfe will a£l on each by different
levers, and make them approach with different veloci¬
ties.
Let AB and CD (fig. 4.) reprefent two parallel
ribs, articulated with the vertebral column at A and C,
where they are equally moveable; and let DB and D E
be two rnyfcles, the former obferving a diredl, and the
latter an oblique courfe. The levers of DB will be
AB and CD, rvhich, as AC is parallel to BD, are evi¬
dently equal •, but the levers of DE will be CF and
AG, which being of different lengths, the mufcle muff
aft with different degrees of force on the different ribs,
fo that it will make CD, on which it afts with the
longed; lever, approach AB, farter than it will make
this latter approach the former.
Corollary.—When bones are not parallel, the mufcles
that crofs in the interval between them, muft fall o-
bliquely on both, as it is impoffible for a ftraight line to
be at the fame time perpendicular to twro other lines,
unlefs thefe be parallel.
6. As all bones move on a centre or axis of motion,
while the mufcular attachments move in a circum¬
ference, the mufcles, in changing the relative pofition
of any two bones, rauft at the fame time, be changing
the direftion c£ their own aftion, and varying their
lever.
Let AB a«d CD (fig. 5.) reprefent parts of twro pa¬
rallel ribs, and let AB be moveable on the centre A,
and let CF and GE be two mufcles inferted obliquely
into AB at F and E. Now fuppofe that by the aftion
of thefe mufcles, AB is brought into the pofition A b.
The points of attachment of the twro mufcles to AB,
will now be f and e, and the mufcles will be Cy" and
G e, having changed their length, fituation, obliquity,
and lever.
7. All mufcles where the points of attachment move in
a circle, draw either towards the centre, or towards the
circumference.
8. If any two bones could, by the aftion of their
mufcles, be made to approach in a parallel direftion, the
oblique mufcles attached to their parallel and approach¬
ing furfaces, would perform a greater extent of motion
Fig. 5-
0 L 0 G Y. Chap. IV-
with a lefs ffortening of their fibres, than any ftraight Of Animal
mufcles attached to the fame parallel furfaces. Motion.
Let AB and CD (fig. 6. and 7.) be parts of twop- 6V ^
ribs that are parallel, and that will continue parallel till ^ ’ ' ’
they are brought in contaft by the aftion of the ftraight
mufcles AC, EF, and BD, or by the aftion of the
oblique mufcles CE and DE (fig. 7.) and FA and FB
(fig. 6.). It is evident, that when the point E comes
in contaft with F, the length of the ftraight mufcles
muft be obliterated, rvhile that of the oblique mufcles
will only be fhortened by c E and r/E in fig. 7. and /A
and ^B in fig. 6.
9. As, however, no two bones can approach one ano¬
ther in a parallel direftion, at leaft by the aftion of a
fingle mufcle, and as no mufcle can continue to aft in a
direftion perpendicular to their twTo approximating fur¬
faces } a mufcle entering them at right angles, when
they are parallel, may be placed fo near to the centre of
motion as to carry the bones through a given (pace,
with a lefs (hortening of fibres than any oblique mufcle
that has the fame origin, but is inferied at a diftance,
and afts through the medium of a longer lever.
Further, a mufcle with a lefs obliquity may be fo fitu-
ated as to carry the bones through a given fpace, wfith
a lefs {hortening of fibres than any other muffle of the
fame origin, but of a much greater obliquity.
Let AB and CD (fig. 8.) be twro ribs, of which AB Fig. §«
is moveable about the centre A •, and fuppofe that by
the {hortening of the ftraight mufcle EF, and of the two
oblique muffles, EG and EH, AB is brought into the
pofition Ab. The points of attachment, after moving in
the fegments Fy Gf, and H/q will now be refpeftively
at y, and //. Now, on the centre E, with the radii
E f, Eg, and Eh, defcribe three different circular feg¬
ments. The difference between the prefent and former
lengths of the moft oblique mufcle EH, will be cH,
while the differences between the prefent and former
lengths of the muffles EG and EF, will be only *G
and )}F refpeftively.
10. The fiiortenings wdfich any muffle fuffers in car¬
rying round the point of its attachment through a given
fpace, wall partly depend on the length of its lever,
partly upon its degree of obliquity, partly on its drawT-
ing peripherad or centrad, and partly on its afting with¬
out or with a pulley (e).
11. The lever of a mufcle, which is varied with every
degree of obliquity, is alfo varied by every change in
the centre of motion. Where bones are connefted by
large furfaces, the centre of motion frequently ftufts
from one part to another •, but in general it approaches
towards that afpeft whither the bone is moving at the
time 3 and as it advances, the mufcles recede, to increaff
their force.
a. The lever of refiftance, as well as of the powrer, is
varied by the feveral changes of pofition j is fometimes
fhortened at the time that the lever of the power is
lengthened 3 and vice verfa.
If
(e) The terms peripheral and central, are employed by Dr Barclay, to denote the afpefts of any organ, accord¬
ing as they refpeft the circumference or the centre of the organ ; and when the termination of thefe words is chan¬
ged from / into d, they denote, like the other terms of his nomenclature, the direftion in which the aftion of thefe
ijparts is exerted. See Barclay’s Anatomical Nomenclature.
Chap. IV. P H Y S I
Of Animal If AB (ng. 9.) reprefent tliefadius, BC the humerus,
Motion. DE the biceps flexor mufcle, and R the refiitance hung
to the diflal extremity of the radius, it will be evident
that, when BA is, by the aftion of the flexor mufcle,
brought into the position B«*, the lever of refinance will
no longer be BA, but BH, equal to a perpendicular
ftraight line drawn from B, the centre ol motion, to the
plane of reliftance 5 and, as the lever of refinance has
been fliortened, the lever of the mufcle has been pro-
porfionably lengthened. Were the radius to refume its
former pofition, the reverfe of thefe circumftances would
take place.
b. Sometimes again, the lever of the power and of the
reiiftance are lengthened or (hortened at the fame time.
Let AB (fig. 10.) reprefent the tibia, BC the femur,
and DEF the crureus mufcle j and that the femur, with
the weight of the body, is to be raifed to the fituation
Be; the centre of motion will, during extenfion, ap¬
proach towards the mufcle at the rotular afpedf, while
the plane of refiftance, as is evident from the figure, will
be approaching to the centre of motion.
c. In the changes of attitude, while a bone is turning
on its centre of motion, the centre itfelf is often at the
fame time deferibing, either the fegment of a circle, or a
line compofed of circular iegments.
Let AB (fig. 11.) reprefent the foot, BC the ^z’#, CD
the thigh bone, and DE the trunk ; and let us fuppofe
that it*is required to bring the three laft, by the aftion of
their mufcles, to the perpendicular BF, fo that BC fhall
occupy the fituntion of BG, CD the fituation of GI, and
DE the fituation of IF 5 the point C on the centre B will
move in the fegment CG, and as C is changing its pofi¬
tion in CG, the point D, which moves round the point
C as its centre, will, if the extenfions be regularly per¬
formed in the fame time, deferibe fuch a curve as DI j
for as the point D mull neceflary move atlantad and fter-
nad, (f) in order to preferve the centre of gravity, the
general direffion of its courfe muft be known 5 and if CG
be divided into equal parts, and at each of the divifions a
circle deferibed with the radius CD, the points in DI, cor-
refponding in number with the points in CG, and at equal
diftances in the fternal direefion, will each be found in
the circumference of one of the circles deferibed fuccef-
fively round the point C as it pafles along the fegment
CG.
In like manner, if the extenfions of CD and DE be
regularly performed in the fame time, the point E will
deferibe fuch a curve as EF, the points in EF being in
the circumferences of the feveral circles fucceflively de¬
feribed round the point D as it moves along the curve
DI.
12. When we examine the ftru&ure of the animal
fyftem, we {hall generally find that the motions of the
bones, as produced by the mufcles, are the combined
effefls of different forces, and hence that a fmall num¬
ber of mufcles is enabled to produce, with fteadinefs and
accuracy, an almoft infinite variety of changes *.
For more on the general fubjedl of mufcular adlion,
/zzr ikZoZzozz, anJ p acc0unt of the principal motions of the hu-
Partn. , , „ e . -r-. ri 1 * , v •
# Barclay
on MufcK-
chap.3.
131
Progreffive
motions.
man bodv, we muff refer to Dr Barclay’s publication.
One of the moil interefting enquiries refpedling ani¬
mal motion, is that of the progreflion of different ani¬
mals, or of the powers of loco-motion.
Thofe animals which poffefs the faculty of changing
their place, exercife this faculty by very different or-
VoL. XVI. Part II.
O L O G Y. 481
gans. Some can only creep, as worms, and many mol- Of An aial
lufea •, others can only fwim, as all filhes, many of the , A
mollufca, and iome of the teftacea. Moll birds^ can
both fly, walk, and run, while a few do not poffeis the
power of exercifing the firft of thefe motions. Ail the
mammalia, and moft reptiles, properly fo called, can
walk, run, climb, leap, and perform a variety of other
motions ; and a few of the former clafs can imitate the
flying ot birds. We lhall briefly examine the mecha-
nifm of thefe different aftions, but by way of introduc¬
tion, ive (hall iirif confider how the adtion of {landing
is performed. FT®
Standing, in moft animals, is folely the effedl of the Standing,
continued action of the extenfor mufcles of all the joints,
as is evident from the circumltance, that it an animal,
while Handing, fuddenly dies, or in confequence of fome
powerful caufe, as a ftrong electric {hock, ceaies to
make the neceffary efforts for preferving the upright po¬
fition, all the articulations of the legs yield to the weight
of the body, and bend under it. In iome animals, how¬
ever, the extenfion of the mufcles is io much afiifted by
powerful ligaments attached to the articulations of the
legs, that they are enabled to continue Handing for a
much longer time, and with much lefs fatigue than motl
others. This is the cafe with birds that perch, and it
is particularly remarkable in the flork, which by means
of this peculiar mechanifm is able to Hand on one foot
for feveral days together.
The aftion of Handing is fomewhat different, accord¬
ing as the animal Hands on twro feet or on four. .
That a body may be fupported in a vertical pofition, Standingoa
it is neceffary that it be fo difpofed as to be in a Hate of two teet.
equilibrium, or that it be fo balanced that a perpendi¬
cular line from the centre of gravity fliall fall within its
bafe. See Mechanics, N° 193, et feq. It is evident
that the more extenfive the bale is on which the 'ody
Hands, the lefs is the danger of its lofing its balance.
Man can very eafily preferve himfelf in the vertical po7
fition, from the broad balls formed by his feet, and
from the great power he poffeffes of feparating thefe to a
confiderable diHance. This latter depends chiefly on
the greater weight of his pelvis., and the length and ob¬
liquity of the neck of the thigh bone, by which this
bone is carried more outward, and removed farther in
its.articulation, than in any other animal. In man, too,
the foot is peculiarly adapted to Hand firmly on the
ground, from the flatnefs of its inferior furface, and from
having the heel bone fo formed as to come in perfect
contact with the ground. The mufcles that move the
foot are alfo very advantageoufly inferted, and the ex¬
tenfor mufcles of the heel are proportionably thicker
than in mofl of the mammalia.
The thigh of man, when in the ereft poflure, is in a
flraighf line with the trunk and the leg, whereas in
quadrupeds, it is fituated clofe upon the flank, and forms
an acute angle with the fpine. On this account, the
thigh bone of quadrupeds is flat, and proportionally
weaker than that of man. The extenfor mufcles of the
thigh are proportionally flronger in man than in the
other animals ; and as the thigh bone moves upon the
pelvis in every direflion, thefe extenfors are in man fo
confiderable, that he is the only animal that poffeffes
what are properly called hips.
In confequence of this Aruflure, the human facral
extremities are furnifhed with a fufficient bafe, and form
3 p very
482 PHYSIOLOGY. Chap. IV.
Of Animal very folid bodies for fapporling tli6 trunk. Man alfo
Motion. pofTeffes feveral advantages for maintaining the general
equilibrium of the body, efpecially the tacility with
which he holds his head in the erect poiture, owing to
the portion of the occipital bone, and the horizontal di¬
rection of the eyes and mouth. See the article Man,
N° 5 and 6.
The quadrupeds that fometimes try to Hand on their
hind feet only, in order that they may either employ
their fore feet in taking hold of fome objeCt, or avoid
keeping their head too low, feem rather to lit than to
Hand. Their trunk refts at the fame time on their hind
feet, as far as the heel, and on the buttocks *, it is Hill
.necelfary, however, that their head and neck fhould be
proportionally fmall, as in monkeys, fquirrels, oppojj'ums,
■b'c. otherwife the weight of thofe parts would be too
great for the force employed in their elevation j but
even when feated, the animal is generally obliged to reft
on the fore feet, as may be pbferved in dogs, cats, be.
Some quadrupeds ufe their tail as a third foot, to en¬
large the bafe of the body : and when it is ftrong, it is
capable of contributing to their fupport for fome time.
We find examples of this in the kangaroos and jerboas.
We have already noticed the mechanifm in the feet
of birds, v/hich enables thefe animals to fupport them-
felves on two legs, though they do not ftand in a verti¬
cal pofition, and though the atlantal part of their bodies
is advanced'more beyond the centre of gravity than the
facral part. Other advantages poffeffed by birds in this
refpeft are, the great fiedlion of the thigh bone and tar-
fus •, the length of the anterior toes, and the length and
, ^ flexibility of the neck.
Standing on An animal which Hands on four feet is fupported on
four feet. a very confiderable bafe) but from the great weight of
the head and neck in thefe animals, their centre of gra¬
vity is nearer to the atlantal than to the facral extremi¬
ties (f). It is evident from this, that in quadrupeds,
the former muft fuftain almoft the whole weight of the
body •, and we find, accordingly, that they are furnifli-
ed with very ftrong mufcles. In ftiort, all that the fa¬
cral extremities feem to wrant in mulcular force, appears
to be transferred to the atlantal.
As in moft quadrupeds the head inclines towards the
horizon, and the neck is often very long, very powerful
means are required to fuftain the former. Thefe means
are furnifhed by the great fize and extenfive attacb-
ments of the mufcles of the neck, and efpecially in ma¬
ny quadrupeds by the cervical ligament. In the mole,
which employs its head to raife confiderable burdens ©f
earth, the cervical mufcles are peculiarly ftrong, and
the ligament is converted into bone.
The body of a quadruped hangs between the four legs,
and by its weight tends to draw the fpine downwards.
This is ccunteradted by the abdominal mufcles, efpe¬
cially by the ftraight mufcles, which produce a curva¬
ture in the oppofite direftion. The abdominal mufcles
act with peculiar force in arching the fpine upwards in
thofe mammalia that are covered with feales or fpines,
and are accuftomed to roll themfelves upon the ap¬
proach of danger, as the hedgehog, the armadillos, and Of Animal
the pangolins. Motion.
O viparous quadrupeds or reptiles, have their thighs w—^
diretfted outward, and the infle&ions of the limbs take
place in planes that are perpendicular to the fpine. In
thefe, therefore, the weight of the body muft a<ft with
a much longer lever, in oppofing the extenfion of the
knee-joints; and accordingly they have the knees air¬
ways bent, and the belly dragging on the ground be¬
tween their legs, whence their name of reptiles.
In walking on a fixed furface, the centre of gravity Walking,
is alternately moved by one part of the extremities, and
fuftained by the other, the body never being at any time
completely fufpended qver the ground. ^
Animals which can ftand eredl on two legs, fuch as Walking on
man and birds, walk alfo on two legs. Tut feveral two feet,
quadrupeds that canndt ftand on two feet but with great
difficulty,,.inay yet move in that pofture for fome time
with fuffieient eafe. This arifes from its being in gene¬
ral lefs painful to walk than to ftand, the fame muicles
net being continued fo long in action. And alfo it is
lefs difficult to correct the unfteady motions by con¬
trary and alternate vacillations (a thing ea’y in walk¬
ing), than it is to prevent them altogether.
When man intends to walk on even ground, he firft
advances one foot; his body then refts equally on both
legs, the advanced leg making an obtufe angle with the
tarfus, and the other an acute one. The ground
not yielding to the point of the foot, the heel and the
reft of the leg muft of neceffity be raifed, otherwife the
heel could not be extended. The pelvis and trunk are
confequently thrown upward, forward, and - feme what
in a lateral direction. In this manner they move round
the fixed foot as a centre, with a radius confifting of a
leg belonging to that foot, which, during this opera¬
tion, continually diminiihes the angle formed with the
tarfus. The leg which communicated this impulfe is
then thrown forward, and refts its foot upon the ground j
while the other which now forms an acute angle with
its foot, has the heel extended in its turn, and in like
manner makes the pelvis and trunk turn round upon the
former leg.
As each leg fupports the body in its turn, as in Hand¬
ing on one foot, the extenfor mufcles of the thigh and
knee are brought into action, to prevent thefe articu¬
lations from yielding j and the flexors a<£l immediately
after, when the leg having thrown the weight of the
body on its fellow muft be raifed before it can again be
carried forward. As the undulalory motion that necef-
farily attends a man’s walking, cannot be perfe&ly regu¬
lated on both fides, he cannot wralk in a perfect ftraight
line, nor can he walk in a direft courfe with his eyes
fhut.
In walking down an inclined plane, or defeending a
ftaircafe, as the advanced leg is placed lower that that
which remains behind, the extenfors of the leg muft a£l
more powerfully to prevent the body from falling back¬
wards. Again, on afeending fuch fituations it is requi-
fite at each ftep, not only to tranfport the body hori¬
zontally,
(f) Thefe terms fignify the fame as fuperior and inferior in man, anterior and pqfterior in quadrupeds; but are
more convenient, as applying indiferiminately to both. Atlantal denotes what is next the atlas ; facral what is next
the facrum. See Barclay's Nomenclature.
Chap. IV.
Of .Vmmal zontaiI)T, as on tvalklng on level ground, but to bear it
, i)n , up againft its own weight, by means of the extenfors of
the knee of the advanced leg, and thofe of the heel of
that which is behind; this is the realon of the knee and
calf of the leg being fatigued in afcending *, and the fa¬
tigue is relieved by inclining the body forward, becaufe
then the lever by which its weight adts on the knee is
fhortened.
Running is only a fucceflion of fhort leaps, and it
will be underftood from what we fliall prefently fay
137 of leaPin6r*
Walking on When a quadruped walks, he firft {lightly bends the
ftw feet, articulations of the hind legs, and then extends them, in
order to carry forward the body, which motion is con-
liderably aided by the extenfors of the knee and the
keel. The bread being thus thrown forward, the fore
legs incline backward, and the animal would fall, did
it not inftantly throw them forward in order to fupport
itielf. It then draws up tire trunk upon the fore legs,
and renews its former efforts.
In this walking, each ilep is performed by two legs,
ene belonging to the fore, and the other to the hind
pair. Sometimes thefe are of the fame fide, and fome-
times thofe of oppofite fides. The motion of a horfe
who fteps forward in the latter way, is termed a pace.
_ In the animals that have the fore feet longer than the
kind ; and have their ftrength chiefly in the anterior
part ot the body, tne principal impulle is given by ex¬
tending the fore foot. The hind foot then rifes to fol¬
low it, audit is not until the moment that the latter
extends itfelf in its turn, that the fore foot is raifed.
This is the manner in which the is laid to move.
But when the forelegs areconfiderably difproportioned
to the others, and particularly when the pofterior extre¬
mities are feebly and badly articulated, as in the floths,
the animal is obliged to drag itfelf forward, by firft ex¬
tending the fore legs, and then bending them fo as to
draw the body after them. Hence the progreffion of the
floth is fo laborious.
Thofe animals which have their fore legs very fhort
in proportion to their hind legs, would be incapable of
fufficiently fupporting their bodies, and muff fall for¬
ward on each impulfe of the latter, had they not the
precaution to make a prancing movement; that is, to
raife_ the anterior extremities entirely off the ground,
previoufiy to their being impelled onward by means of
the hind feet. Accordingly, fuch animals cannot in
pronriety of language be faid to walk ; they only move
.forward by leaps. 1 his is the cafe with hares, rats,
and particularly jerboas. Indeed, thefe animals cannot
be fa:d to walk at all, except in the a&ion of afcendiim.
When they attempt to walk flowly on level ground,
they are obliged to move themfelves by the fore feet’
and merely to drag after them the hind pair. This may
be obferved in rabbits, and ftill more diflindly in
138 fr°gs-
4feaping. In leaping, the body rifes completely from the earth,
and remains without any fupport for a fhort period, the
duration ot which depends on the force with which the
leap has been made. 1 his addon is Performed by a hid¬
den extenfion of all the mufeies belonging to the facral
articulations, immediately after they have undergone an
unufual degree of fledion. By this general extenfion
the e articulations receive a violent motion, the impulfe
9f which is communicated to the center of gravity of
PHYSIOLOGY. 48.5
the body, and it is thus projeded with a determined ve- Of Animal
locity, which is more or lefs in oppofition to its weight, ^lotion.
1 he projedile force and extent of the leap depend on " v
the proportional length of the bones, and ftrength of
the mufcles. Thofe animals, therefore, leap beft that
have the facral extremities longer and thicker than the
atlantal ; as the kangaroos, jerboas, frogs, aliiccr, gnjllk.
fens, iyc.
Small animals leap proportionally much farther than
the larger fpecies; and we know of none whofe mufeu*
lar ftrength, in this way, can be put in competition with
that of a flea, which on a moderate computation is known
to leap to a diflance of at leaf! 20c times its own length.
The diredion of a leap depends on the fituation of the
centre of gravity with refped to the member by which
the impulle is given. Hence, only man and birds can
leap vertically, becaufe they alone have the trunk fitua-
ted above the members by which the leap is effeded.
Quadrupeds, and moil infeds, can only leap forward ;
but fpiders, which have feveral long feet on each fide of
their body, can alfo leap fideways.
Running confifts of a feries of low leaps performed al- Rumamg.
temately by each leg. It differs from walking, in the
body being projeded forward at each ftep, and in the
hmd foot being raifed before the anterior touches the
ground. It is more rapid than the quickeft walk, be¬
caufe the acquired velocity is preferved, and increafed
at each bound by a new velocity. Running, therefore,
cannot be inftantaneoufly fufpended, though a flop may
be put to walking at each ftep.
In running, the animal inclines its body forward,
that the centre of gravity may be in a proper pofition
for receiving an impulfe in that diredion from the hind
leg; and it is obliged to move the fore leg rapidly for¬
ward, to guard againft falling.
Man varies his manner of running, only bv lakir.p-
longer or fborter fteps, or giving to this motion a grea£
er or lefs degree of rapidity ; but quadrupeds vary this
motion by the different order in which they raife each
foot, or bring it to the ground.
I rotting is a mode of running in which the feet di-Trotting,
agon ally oppofite rife at once, and fall at once, each
pair alternately, but in fuch a manner, that for a mo¬
ment all the four feet are off the ground. This pro¬
duces a regular motion, and the found of the animal’s
fteps are heard two and two in fucceflion.
Galloping is a running motion in which the animal Gahopinrr,
raifes the anterior feet at each ftep, and throws the body * * £*
forward by the extenfion of the pofteiior feet. When
the two fore-feet defeend at the fame time, and are fol¬
lowed by the two hind feet alfo defeending together,
the motion is called a full gallop, which is the molt
rapid a horfe can perform, and the only mode of running
in dogs, hares, Sec. In this kind of gallop the fteps of
the horfe are like wife heard by two beats at a time.
The common gallop is when the two fore-feet are lifted
unequally, and fall one after another. This may be
divided into gallops in which the horfes footfteps are
heard by a feries of three or four beats, becaufe the po¬
fterior feet may fall to the ground either both together,
or one after the other.
There are feveral kinds of animals which leap by the
means of organs different from feet, but always by a
hidden extenfion of feveral articulations.
Serpents leap by folding their bodies into feveral u«-
3 P 2 dulationsj
48 t
P H Y S I
Of A n:ma\ dulations, which they unbend all at once, according as
^ ^ 100* » 1 - * Y! • *      *— 1 ^. 1 ^ t 4 ■« -r -4 x-x P 1*% * ■* T -*• I" t ^ •
I43
Climbing.
T43
Flying.
they wifn to give more or lefs velocity to their motion-,
home may be affifted by the fcales of their belly, which
they can elevate and deprefs, but only a few genera are
capable of employing this means.
Some fifhes alfo leap to the tops of cataratts by bend¬
ing their bodies ftrongiy, and afterwards unbendmg
them with an elaftic fpring.
The long-tailed cray-jijhes, particularly the primps,
leap by extending the tail after it has been previoufly
bent under the body.
The larva of the jly, vulgarly called the maggot,
forms itfelf into a circle, contrabfs itfelf as much as pof-
fible, then fuddenly unbending, darts forward to a con-
liderable diftance.
The motion of climbing, fo ufeful to many of the in¬
ferior animals, conlifls in hanging from, and ftrongiy
grafping any object fufceptible of being feized by the
fingers, toes, or tail, and thus rifing, by fucceflive efforts,
in a direftion oppofite to the animal’s weight, from
this explanation it is evident that thofe animals which
have the divifions of their extremities moil diftintt and
flexible, will be the belt climbers 5 and accordingly we
find that the animals called quadrumanous, as the apes,
lemurs, and a f&w others, perform this action in the
moft perfefl manner. Man is but an indifferent climb¬
er, as he can only grafp with his hands. In oppojjums,
ant-eaters, and Jloths, one of the toes is diftin6I, like the
thumb in man, apes, and lemurs j or elie they have a
confiderable protuberance on the heel, which has the
fame effeif. Many animals, as fome of the monkeys,
fome fpecies of oppojfum and ant-eater, the mams, &c.
have a very flexible prehenfile tail, which aflifts them
in climbing. The animals of the cat genus have very
fliarp talons, by which they are materially affifted in
this kind of progreflion, as they enable them to adhere
firmly to the bark of trees, &c. Creepers, nut-hatches,
woodpeckers, and other climbing birds, fupport them-
felves in a fimilar manner.
The motion of flying, by which an animal can fup¬
port itfelf for fome confiderable time in the air, can pro¬
perly be faid to be performed only by birds : for though
bats can imitate this motion with tolerable fuccefs, and
the galiopithecus, flying-fquirrels, and flying-oppoffums,
appear to fly from one tree to another, the motion of
the former cannot be fupported for fo long a time as
that of birds ; and the motion of the latter animals can
be confidered only as a leap, aflifted and prolonged by
the oppofition given to the air, by the membranous ex-
panfion between their limbs.
When a bird defigns to fly, it firft darts into the air,
either by leaping from the ground, or by throwing it¬
felf from fome height. In the mean time it raifes the
whole of the wings which had till then remained folded,
and which it unfolds in a horizontal direction by extend¬
ing the bones. When the wings have thus acquired all
the fuoerficial extent of which they are fufceptible, they
are fuddenly depreffed, till they form, with the vertical
plane of the body, an angle that is obtufe upward, and
acute downward. The refiftance which the air gives
to this motion fuddenly performed in it, produces a re-
aftion on the body of the bird, and thus moves it for¬
ward as in ordinary leaps. This impulfe once given,
the bird refolds the wings by bending the joints, and
O L O G Y. Chap. IV.
repeats its efforts by another ftroke. As the velocity Of Animal
thus acquired in afcending is gradually diminiftved by -nouon.
the effedt of gravitation, a moment occurs in which it v
ceafes, and in which the bird tends neither to aicend
nor defcend. If at thb moment it gives a new ftroke
with the wings, it acquires a new aicending velocity,
by which it will be carried as far as before, and by re¬
peating thefe efforts, it will afcend in a uniform man¬
ner. If this fecond ftroke be made before the velocity
firft acquired is loft, an additional impulie will be re¬
ceived } and by a continuance of this action the bud
will afcend with an accelerated motion, if the wings
do not vibrate when the aicending velocity is loft, the
bird will begin to delcend ; and it it allow itfelf to fall
down to the point from which it let out, it cannot ai¬
cend as high as at firft, but by a much ftronger exer¬
tion of the wings; but if it feizes in the fall a point fo
fituated that the acquired defending velocity, and the
fmall fpace which it has to fall down reciprocally ba¬
lance each other, it may, by a feries of equal vibrations,
keep itfelf at the fame height.
When a bird willies to defcend rapidly, as when it
darts upon its prey, it altogether fuppreiles the vibra¬
tion of its wings, and thus falls by its own gravity.
While defending, however, it may fuddenly break its
fall by extending its wings, and this fufpenfion is called
a recover.
We have as yet confidered only the vertical flight of
a bird. To fly horizontally, it muft rife in an oblique
direblion, and make a new movement of its wings,
when it is ready to defcend below the point from which
it departed ; but in this way it will not fly in a ftraight
line, but will defcribe a feries of curves lo very much
depreffed, that the horizontal will overcome the vertical
motion. In order to afcend obliquely, the bird muft
make quicker vibrations of its wings, and to defcend in
a fimilar dire&ion, the vibrations muft be flower.
The deviations of flight to the right or left are chiefly
produced by the unequal vibrations of the oppofite
wing 5 thofe of the left wing carrying the bird to the
right, and vice verja. T-he more rapid the flight is
forward, the greater is the difficulty of one wing fur-
palling the other in the velocity of its vibrations, and of
courfe the deviation fideways is the more difficult. Hence
birds which fly with the greateft velocity make large
circles in turning.
The tail, when fpread out, contributes to fuftain the
pofterior part of the body. If it is depreffed when the
bird has acquired a progreffive velocity, it prefents an
obftacle which elevates the pofterior part of the body,
and depreffes the anterior. If it is turned up, the con¬
trary effebt is produced. Some birds incline to one
fide, to affift them like a rudder, when they wifti to
change their horizontal direblion.
The ftrucfure of moft birds peculiarly adapts them
for rapid motion through the air, and for fuftaining
themfelves in this element with the greateft facility.
See Ornithology, N0 37- . . , 144
The abfion of fwimming, like that of flying, nearly Swimming,
refembles leaping, except that, like flying, the leap does
not take place on a fixed fin-face. A great variety of
animals, befides filli, and moft of the other inhabitants
of the waters, are capable of fwimming. This abfion is
performed with confiderable eafe by feveral of the mam¬
malia,
Chap. IV. P H Y S.1
Of Animal malia, even by the bulky elephant, and the unwieldy hip-
Motion. popotamus j by many tribes ol birds } by leveral rep-
tiies and ferpents, and by lome infedts.
The* organs employed by fibres, in making their way
through the water, are their fins, tail, and.air-bladder •,
the two former exerting the ncceffary motions Ime the
wings of birds, while the latter, by being compreffed or
expanded, caufes the neceffary changes in the fpeeme
' ' gravity of the body, and thereby readers the animal
more or lefs buoyant. The fwimming of fillies has been
treated of with fufficient minutenefs under IcilTtlYOLOGY,
chap. in. led. d* tn which we refer the leader.
The cetacea employ much tire fame means as filhes •,
but in them ihe principal eilorts of the tail are made
in a vertical diredion, and the ufe of the air-bag is fup-
plied by lungs, which they can comprefs and dilate at
pleafure, by the adion of the diaphragm, or the inter-
coltal mufcles. See CETOLOGY. <
The fwimming of mammalia, and of water biros,
is per±ormed by means of the legs and feet, which are
uied like oars, to propel the bouy forward by toe refill-
ance which they make to the water in tbe contiaiy di-
redion. Hence thofe quadrupeds and birds that have
fiat or webbed leet, fwim moll eafily, as the refilling
furface is the greateft. Of all the mammalia, man has
the molt occalion to ufe Iris hands in fwimming, on ac¬
count of the greater proportional weight or ins head..
Serpents, and the larvae of fuen imeds as lometimes
inhabit the waters, perform the adion of fwimming by
rapid intledions of the body like an eel or a leech.
The larvae that are moll commonly found in the waters
are thofe of the water beetles ^ the hydvop h it us, the duy
fries, the aquatic tipuhv, 2.wA. gnats.
No animal walks without legs, or flies without wings
(if we except the flying fith, whofe fins enable it rather
to fpring than fly) ; but there are many that fwim with¬
out fins, and that leap and creep without any legs. The
rapidity of movement is not proportioned to tfie number
of inftruments that are employed : if the fpout-filh be ob-
ferved to move flowly with one leg, the fea-urchin moves
Hill more flowly with many thoufands i theoyfler mo\es
by fquirting out water •, the feallop by the jerk of its
{hell, and when in the water it riles to the furface and
fails before the wind.
Many animals are formed by nature to fly, walk, leap,
and fwim,: the fate of thofe is rather uncommon whofe
mufcles or feet are by nature attached to their integu¬
ments ; the lobfter is obliged to throw off its fliell, and
the caterpillar all its feet, with the Ikins, and in that fi-
tuation to remain ftationary till it receive new ihfl.ru-
ments of motion.
Whoever has read the celebrated work De Main Ani-
malium, needs not to be told that, befides the organs
which are here mentioned, the form, the ftrudure, and
even the fpecific gravity of the body, as depending on
' the nature of the bones and mufcles, or as varied by air-
velicles and bubbles, with a great variety of other cir-
cumftances, are neceffary to explain the different pheno¬
mena of locomotion.
As to vegetable motions, they evidently depend on
external agents : the wings of feeds only fit them to be
carried by the wind, their fpecific gravity to float in the
water, and their legs or tentacula to adhere to bodies
that are in motion j the Angular motions which have
o L o G Y. 4&5
been aferibed to deeping, to waking, to fenfation, and Of Animal
... . . , , , • 1 r* , Mntmn.
*45
145
I47- ,
Vegetable
motions.
volition, in the vegetable kingdom, ieem only the con- 0‘<jn~
fequence of light, heat, moifture, and fuch itimulants,
adling inviflbly or with fecret influence : the opening
and doling of the meteoric flowers are always corre-
fpondent to the Hates of the atmofiphere j and the open¬
ing and doling of the equinoftial and tropic flowers, to
the light, the length or Ihortnefs of the day.
The principal intentions of locomotion are to get Ufcs of lo-
food, to flam danger, to promote intercourfe and di-coinot‘on*
fperfe the fpecies.
There is perhaps no part of phyfiology which is more
important than the relations which lubfiff between tb.e
different functions of the living body j but it is a part of
the fubject which is as yet but little underftood. We
regret that our limits will not permit us to pay all the
attention to it which we could wilh. We fliail, how¬
ever, briefly notice under each fun&ion, the principal
relations that are found to take place between it and
thofe which have been previoufly confidered. 149
Befldes the dependence w hich animal motion has, in Mutual re-
moil inllances, on the nervous fyltem, (fee N°i 11.) we find !a^°RS
an evident fympathy between thefe two functions in a va- fdtion and.
riety of phenomena. A violent emotion or impreflion on motion.
the nerves often throws the limbs into convulfive agita¬
tions j fpafmodic affections are relieved, or fometimes re¬
moved, by the coming on of delirium j and thefe fymp-
toms will alternate with each other : a compreflion of
the brain, or of fome large nervous trunk, produces ge¬
neral or partial wrant of motion, and when this compref-
fion is removed, the mufcles for the moll part recover
their ufual aflion 5 an attack of epilepfy is often preced¬
ed by the fenfation of a Itream of vapour commencing in
fome external part, and riling to the brain. T'hefe, and
many other phenomena that might be mentioned, fully
prove the fympathy between the nervous and mufcular
fyftems; and with this enumeration wre mult difmifs the
fubjedt.
Chap. V. Of Digejtion.
I5°
The neceflity of repairing the w^afte of the body is Appetite
announced in all animals by the feelings of hunger and tor tood. -
third: j the former of which intimates the occalion for
folid, the latter for liquid food. This imperious necef-
fity overrules all the other affedlions of the vital prin¬
ciple, and every other appetite often remains fufpended
till that neceflity be fatisfied. It is diflicult to aflign
the final caufe of thefe lingular fenfations, but probably
our refearches on that fubjedt are rather curious thanufe-
ful. Whatever be the ultimate end of thefe appetites, wre
readily perceive how7 much they are influenced by habit.
We find that when we are accuflomed to take food at
particular times, the appetite, under ordinary circum-
flances, always reminds us at thefe times, of the occafion,
whether real or apparent, for receiving a new fupply.
By this influence of habit fome animals, efpecially man,
are accuftomed to take feveral meals in a day, while
others can fall for days, or even weeks, together. The
appetite for food alfo varies confiderably at different ages.
It is more lively and more imperious in infancy and early
childhood, and in general in thofe animals who have not
yet acquired their full growth 5 it is on the contrary
W’eaker in advanced age, and when the body ceafes-xb
increafe -
15l
Plants and
fome ani¬
mals live on
water and
air alone.
Of digeftion.
P H Y S I
inereafe in fize. ll is more frequently renewed in the
llrong and healthy, and thofe who are accuitomed to la¬
borious occupations or active exercifes.
We know that in the natural Hate of the animal body,
the appetite for food is influenced by the nature of the ali¬
ment on xvhich the animal is accuftomed to fubfift. Many
animals live entirely on vegetable food, and thefe have no
appetite for animal fubftances, and even rejeft thefe when
offered to them. On the other hand, many tribes live en¬
tirely ,on animal food, and either refui'e vegetable, or, if ob¬
liged by neceffity to employ it as food, do not appear to
derive nourilhment from it. We find, hovvever, that it is
in the power of habit to remove thefe appetites ; that a
horfe or a flieep may be taught to live on animal food,
while a dog or a cat may be fupported entirely on vege¬
table fubftances. A few animals are capable of fubfift-
ing on almoft every kind of animal or vegetable fubftan¬
ces,4 or are omnivorous.
Many animals are capable of being fupported by v:a-
ter and air alone. We knotv that feveral fifties, as the
minow, the gold and filver fifti, &c. will live for a lon^
time in a veffel containing pure water, and freely expof-
fed to the air. Rondelet (a celebrated writer on. fifties in
the 16th century) relates a remarkable inftance of this.
He kept a fifh during three years in a veffel that ivas
conftantly full of very pure water. It grew to fuch a
fize, that at the end of that time the veffel could no long¬
er contain it. Leeches are often kept for feveral years
with no other nutriment but water, and that not very
often changed. There is good reafon to believe that the
foie food of plants confifts of water and air, and that the
foil in which they grow anfwers fcarcely any other
purpofe than that of preferving and condufting thofe ne-
ceffary aliments.
It has been fuppofed that fome animals are capable of
fubfifting on matters that appear to contain no nutnticus
principles, fuch asfand, hair, and wmol. Borelli long, ago
conceived this opinion, from obferving that in nftany te-
ftaceous animals which he differed, the alimentary tube
contained nothing but fand. It has often been remark¬
ed, that horfes, cows, and ftieep, when deprived of their
ufual nourilhment, will lick their bodies, and fwallow
down the hair, or, in the cafe of fheep, wall tear off and
{wallow each others wool. If we con fide r the nature of
thefe liibftances, we think there is no reafon to fuppofe
that they anfwer any other purpofe than diftending the
alimentary canal or ftomach, and thus in fome^ meafure
COunterafting the effect of hunger.
The fubject of food in general has been already treat¬
ed of, under Aliment, and in Materia Medica,
Part I. N° 175 and the funflion of digeftion, as far as
it relates to man, has been confidered under AXatomy,
N° 106, 107, and under Chemistry, N° 2548. It re¬
mains for us here only to make a few obfervations on the
comparative phyliology of this function.
Digeftion differs confiderably in the various claffes of
i. animals, both as to the organs by which it is performed,
and as to the fimplicity or complex nature of the opera¬
tion itfelf. The general variations that take place in
the organs of digeftion, have beeh mentioned under the
comparative part of Anatomy, N° 152, and are fully
treated of by Cuvier, in his Lefons d'Anatomic Com-
parte, tome iii, and Blumenbach, in his Comparative
Anatomy, chap. 6. and 7.
Th the more perfect animals, digeftion fuppofes a
3
O L O G Y. Chap. V
feries of operations, from the time that the food enters Of
the mouth, tilt the nutritious parts of it are taken into Digeftion.
the circulating fyftem. Thefe operations are, majhca- ' ' v~' J
tion, infalivahon, deglutition, chymijication, and chylijica-
tion. _ ,5S
Mcjlication is performed by means of teeth, and there-Maftica-
fore can fcarcely be faid to take place in thofe animals bon.
that are not furnilhed with thele organs. We know that
all mammalia except thofe which Cuvier calls edentate,
as the ant-eaters, pangolins, and platypus, have teeth,
fitted both for dividing and chewing their food j but
here an important difference takes place. Thofe ani¬
mals which live chiefly on animal food, have moft of
their teeth lharp and pointed, for the purpofe of feizin^
and tearing their prey, while the graminivorous and gra-
nivorous animals have very large and ftrong grinders, in
which the hard fubftance commonly called enamel (or
what Blake , calls corpus Jlriaturn, *) forms alternate * ^
layers with the bony part. Such are alfo found in moft ^ Struc-
reptiles and ferpents, and in many fifties j but in fome aiture and
thefe they feem lefs to ferve the purpofe of dividing the formation
food, than to feize and retain it till fwallowed. Birds
have no teeth, though fome of them have the mandibles
of the bill fo formed as to divide and cut in pieces their
food.
During maftication the food is mixed with the faliva,
and is thus better fitted for eafy folution in the ftomach. tion.
This infalivation of the food may, how ever, take place,
without previous maftication. It is common for fer¬
pents to fwallow their food whole ; but in order to faci¬
litate its paffage down the throat, they firft befmear it-
all over with their mucous faliva. In many animals, a
procefs fimilar to infalivation takes place, while the
food remains in the mouth. In feveral fpecies of the
ape tribe there is a pouch fituated on each fide of the
jaw7, and in thefe pouches the greater part of the food is
retained, not merely as fome fuppofe, to ferve as a fu¬
ture meal, but to undergo a dilution by the fluids that
are there fecreted. In granivorous birds, the food is
firft received into a membranous bag, formed by a dila- %
tation of the gullet, and commonly called the crop,
. where it * macerated by the fluids that are there fepa-
rated by means of glands or exhaling veffels, and paffes
down, as the animal requires, to be further prepared by
the ftomach. The buftard, indeed, though a granivo¬
rous bird, has no proper crop, but the gullet it furnilhed
with numerous an dn'large glands.
For an account of the chemical nature and properties
of faliva, fee Chemistry, N° 2723. I57
The operation of deglutition depends chiefly on the Degluti.
aiftion of the tongue, and on that of the mufcles wdiichtion,
furround the pharynx and gullet. It is more or lefs
fpeedy in proportion as thefe are more or lefs aftive and
vigorous. Moft animals, after having once fwallowed
their food, do not receive it again into the mouth •, but
this takes place in feveral tribes, and is called rumina¬
tion, or chewing the cud.
Rumination takes place chiefly in thofe animals that Ru^aS-
feed on herbage, and Lave not a mufcular ftomach *, fuchtion>
as all the tribes that Linnaeus has ranked under the or¬
der pecora. In thefe the food, after being {lightly
chewed, is received into the firft ftomach, and after re¬
maining 'there for a Ihort time, it is gradually brought
by a retrograde aftion of the gullet into the mouth,
where it undergoes a complete trituration and infaliva-
\
Chap. V.
1S9
€hym:fica-
tion.
160
Organic
aClion of
the fto-
mach.
tion, and is tLen conveyed into the 2d, 3d, and 4th
• liomachs, to be mixed with the gadric juice.
Some of thofe birds which have a diluting lire or in-
gluvies, feem likewife to ruminate. This in the parrot
was obferved by the gentlemen of the French academy.
(It has fmee been obferved in rooks, macaws, cockatoos,
and others: and Mr Hunter, to whom phyiiology is fo
much indebted, difeovered that the male and the female
pigeon fecrete in their mgluvies a certain liquor for
feeding their young ; and that mod: kinds of w hat have
been thought ruminating birds do very often in expveffing
their fondnefs regurgitate their food. Yet both this
and another fpecies of regurgitation which is very com¬
mon with thofe animals that fwallow indigertibfe fub-
Aances with their food, Ihould be carefully diilinguilhed
from rumination. For a farther account of rumination,
and of the digeftive organs of ruminating animals, fee
Comparative Anatomy, N° 228—234. and Phi/. Tranf.
1807, Fart ii.
The food having entered the fto'rach, undergoes in
that organ proceffes that are partly mechanical, or ra¬
ther organic, and partly chemical, depending on the
ilruclure of the flomach, and the nature of the juices
fecreted into its cavity. Ey thefe actions it is reduced
into a pulpy lubfianee commonly called chyme.
The organic adlion of the Itomach is greater or lefs,
according as this organ is more or lefs mulcular. There
are many animals, chiefly birds of the granivorous
tribes, that have a very mufcular llomach, commonly
called gizzard, capable of grinding, not only the grains
received into it, but even of reducing to powder fmall
pieces of glafs, and of blunting the points of needles
and lancets. Thefe fadfs wTere firff proved by Borelli,
who introduced into the gizzards of fowls, nuts, filberts,
hollow fpheres of glafs, hollow cubes of lead, {mail py¬
ramids of wood, and feveral other fuhftances, which he
found were either crufhed together, or broken to pieces,
lie computer the power exerted by the ftomacb of the
Indian cock as equal to the preffure of 1350 pounds
weight. Thefe experiments were repeated and verified
by Spallanzani.
Some animals that are not polTeiTed of a mufcular
flomach have, within that organ, teeth, or other hard
bodies, for the purpofe of breaking or grinding their
food. This is the cafe with many of the crullaCea, as
crabs and lobllers.
A great many animals have w’hat Spallanzani calls in¬
termediate llomachs, i. e. not fo mufcular as the gizzard
of fowls, nor fo membranous as the flomachs of rumi¬
nating animals 5 this is the cafe with many birds, as ra¬
vens, crows, herons, &c. The ftomachs of thefe animals
are pcffeffed of confiderable force, though this is not
nearly equal to that exerted by the gizzard. Thefe ani¬
mals poflefs the power of rejedling by the mouth the
fubftances that are incapable of digellion in the ftomach,
every nine, or fometimes every three hours.
The animals wdth membranous llomachs are very
numerous, comprehending man, mod beads and birds of
prey ; many reptiles, fnakes, fidi, &c. The domachs
of thefe animals are fufceptible of but little mufcular
aflion, though in many fpecies they both contradl upon
the food, and reje£l it through the gullet, on various
occafions. Birds of prey, like the ravens, crows, &c.
polTefs the power of rejefting, in the form of pellets, the
P H Y S I O L O G Y. 487
indigefiible parts of their food, which ufually takes place
every 24 hours. Digeftior.^
A mod intereding paper by Mr Everard Home is l6vt
published in the Pbilofophical Tralifa&ions for 1807, Difroveries
part ii. on the fhu&ure and functions of the domachs of of Mr
various animals. We regret that we can here give l;Ionne‘
little more than the relulls of his inquiries.
-A From previous invettigations refpefiing the flomachs
of ruminating animals, Mr Home was led to believe
that the fourth Aomach in thefe tribes was either always,
or during digellion, divided into two portions, each
performing a different office in tfie digeflive procefs 5
and he even conjedlured, that a fimilar divifion might
take place in other animals.
Mr Home has examined the llomachs of a great va¬
riety of animals, and invedigated the progrefs of di-
gedion in ruminants, the hare tribe, which occafionally
ruminate, the beaver, dormoufe, water-rat, common rat,
inoufe, horfe, and afs, kangaroo, pecare, hippopotamus,
elephant, the cetacea, fowls, and ladly in man. i62
The human domach appears to be the uniting link Human fta-
between thofe that are fitted only to diged vegetablemach the
fubdances, and thofe of animals that are entirely carni-iin^ ^e"
vorous; and yet we find, that in its internal ftrutture nTvorous^"
it is in every material refpeft fimilar both to thofe of the and phyti-
monkey and fquirrel, which ufually diged only vege- vorous fto-
table food, and to thofe of carnivorous animals. machs.
The human domach is occafionally divided into a car-
cardiac and a pyloric portion, by a mufcular contraftion dmc and
fimilar to thole of other animals j and as this circum-/>y/or*V por-
dance has not before been noticed, it is proper to betion-
more particular in deferibing it.
The fird indance in which Mr Home obferved
this mufcular contraction in the human domach, was
in a woman who died in confequence of being burnt,
and who had been unable to take much nourilhment
for feveral days before her death. The domach was
found empty, and was taken out of the body at a very
early period after death. It was carefully inverted
to expofe its internal furface, and gently didended
with air. The contraftion was fo permanent, that
after the domach had been kept in water, in an invert¬
ed date, for feveral days, and at different times diflended
with air, the appearance was not altogether dedroyed.
Since that time, Mr Home has taken every opportu¬
nity of examining the human domach diortly after
death j and he finds that this contraction, in a greater
or lefs degree, is very generally met with. He is of
opinion that this effedl is not produced by a peculiar
band of mufcular fibres, but that it arifes from the muf¬
cular coat, in the middle part of the domach, being
thrown into adion to a greater or lefs extent according
to circumdances. When this part of the domach is ex¬
amined by diffe&ion, its mufcular fibres are not to be di-
dinguilhed from the red. If the body be examined fo
late as 24 hours after death, this appearance is rarely
met with j a circumdance which accounts for its not
having before been particularly noticed.
That the food is diffolved in the cardiac portion of Food fird
the human domach, is proved by this part only being d’ffdved in
found digeded after death j the indances of which are^.ie car~
fufficiently numerous to require no addition being made^:.pC>J>
to them. This could not take place unlefs the folvent ’
liquor was depofited there. Mr Hunter goes fo far as
to
483
Of to fay ia Ills paper on this fubjecl, “ there are few dead
Oigeftion. ^0jjes Jn which the ttomach at its great e’ad is not in
' fome degree digefted.”
bwt the That the chyle is not formed there, and that it is
chyle form-commonly formed before the food paffpfi through the />y-
ed in the /oruSf is proved by the refult of fome experiments made
pyloric por-j^y |Y[r Hunter upon dogs, in the year 1760. The dogs
were killed while digeftion wras going on ; and in all, the
food was lead diffolved, or even mixed, towards the
great end of the ftomach, but became more and more fo
towards the pylorus, juft within which it was mixed with
166 a whitilh fluid like cream.
Solvent From the refult of thefe experiments, as well as from
liquor fe- the analogy of other animals, it is reafonable to believe}
err ted by ^1- tjle glands fituated at the termination of the cuticu-
the'1"ullet' lar ^n‘nk the oefophagus, which are deferibed by Mr
S ‘ ” Home, fecrete the folvent liquor, which is occafionally
poured on the food, fo as to be intimately mixed with it
before it is removed from the cardiac portion} and the
mufcular contraftion retains it there, till this takes place.
'>67 Such contraction being occafionally required in the
Curvature ftomach, accounts for its being more or lefs bent upon
of the fto- as ^ jqfts ftruClure it is more readily divided into
counted for.two portions, by the action of the mufcular fibres at that
part where the angle is formed.
This contraction alfo explains why the contents of
the ftomach are not completely difeharged from the firft
effeCt of an emetic ; and by it Mr Home thinks we may
explain the cramp of the ftomach, And fome kinds of in*
digeftion.
t6S After comparing the flomachs of feveral carnivorous
Ornitho- an;mals wfth that of man ; in tracing the gradation from
real link carnivorous beafts through the bat tribe to birds of prey,
between Mr Home remarks that “ the only real link between
quadrupeds the ftomachs of quadrupeds and birds is that of the orni-
aud birds. tftorinchus (0r platypus), which, however, is more an
approach to the gizzard, being lined with a cuticle con¬
taining land, and having the fame relative fituation to
the oefophagus and duodenum. The food of this animal
is not known } it is probably of both kinds; the papillae
at the pylorus, which appear to be the fecretory duCts
of glands, are peculiar to it.
169 From the faCts and obfervations brought forward in
General t|fts valuable paper, Mr Home deduces the following
conclufions. ^eneral COnclufions. “ That the folvent liquor is fe-
creted from glands of a fomewhat fimilar ftrufture in all
animals, but much larger and more confpicuous in fome
than in others.
« That thefe glands are always fituated near the ori¬
fice of the cavity, the contents of which are expofed to
their fecretion.
“ That the vifeid fubftance found on the internal
membrane of all the ftomachs that were examined re¬
cently after death, is reduced to this ftate by a fecretion
from the whole far face of the ftomach, which coagulates
albumen. This appears to be proved, by every part of
the fourth cavity of the calf’s ftomach having the pro¬
perty of coagulating milk.
“ This property in the general fecretion of the fto¬
mach leads to an opinion, that the coagulation of fluid
fubftances is neceffary for their being afted on by the
folvent liquor; and a praftical obfervation of the late
Mr Hunter, that weak ftomachs can digeft only folid
food, is in confirmation of it.
“ That in converting animal and vegetable fubftances
Chap. V.
into chyle, the food is firft intimately mixed with the Of
general fecretions of the ftomach, and after it has been Dig(:^10n^
added on by them, the folvent liquor is poured upon it, v~““
by which the nutritious part is diffolved. This folution
is afterwards conveyed into the pyloric portion, where
it is mixed with the fecretions peculiar to that cavity*
and converted into chyle.
“ The great ftrength of the mufcles of the pyloric
portion of fome ftomachs will, by their action, comprefs
the contents, and feparate the chyle from the indigeftible
part of the food.
“ In animals whofe food is eafy of digeftion, the fto¬
mach confifts of a cardiac and pyloric portion only ; but
in thofe whofe food is difficult of digeftion, other parts
are fuperadded, in which it undergoes a preparation be¬
fore it is fubmitted to that procefs.” 1_Q
The action of the juices of the ftomach, or of what A&ion of
we call the gq/iric juice, appears to have much more ef- the gaftnc
feft in the procefs of chymification, than the mufcular jnice,
action of the ftomRch, though the diffolvmg power of
this fluid feems to be proportionally lefs in thofe ani¬
mals that have the moft muicular ftomachs. The ga-
ftric juice of granivorous birds is capable of difiblving
flefh ; but when this is entire, it requires four or five
days for folution •, whereas when bruiled, hall that time
is fufficient. Even grain is not diflblved in it except
when bruifed. The gaftric juice of animals with inter¬
mediate ftomachs diiiolves ftefh and cartilage, but not
bone. It is incapable of diffolving entire feeds. In
animals with membranous ftomachs, the gaftric juice is
extremely aftive, and feems to be almoft the only agent
in the digeftive procefs. In fome of thele animals, ^
however, as the ruminating tribes, this fluid has no ef-
fedt on the food, unlefs it be bruifed, or thoroughly
mafticaied. Spallanzani found, that owls digeft fleih
and bones, but not grain ;—that the gaftric juice of the
eagle diffolves bread and bone, and even animal and
vegetable matters, when it is taken out of the body •,—
that a wood pigeon may be gradually brought to live
on flefh ;—that the owl and falcon do not digeft bread *
—that the gaftric juice of the dog diffolves even the
enamel of the teeth.
Hence, in every order of animals, the gaftric juice is
the principal caufe of digeftion, and it agrees in all in
many properties, and differs in others. In the frog, the
newt, fcaly fifties, and other cold-blooded animals, it pro¬
duces digeftion in a temperature nearly equal to that oi
the atmofphere. In warm blooded animals it is capable
of diffolving the aliment in a degree of heat lower than
that of thefe animals. In them too the food is digefted
in a few hours, whereas in the oppofite kind it requires
feveral days, and even weeks, particularly in ferpents j
likewife, the gaftric juice of the gallinaceous clafs can
diffolve only bodies of a foft and yielding texture, and
previoufly triturated ; whilft in others, as ferpents, the
heron, birds of prey, and the dog, it decompofes fub¬
ftances of great tenacity, as ligaments and tendons *
and even of confiderable hardnefs, as the moft compadl
bone. Man belongs to this clafs, but his gaftric juice
feems to have no action on the hardeft kinds of bones.
Some fpecies, likewife, are incapable of digefting vege¬
tables, as birds of prey ; but man, the dog, cat, crows,
&c. diffolve the individuals of both kingdoms alike, and
are omnivorous, and in general their gaftric juices pro¬
duce thefe effects out of the body.
P H Y S I O L O G Y.
For
Cliap. V.
Of For an account of the chemical nature and properties
■ Digcftion., 0p ,-ijg gaftric juice, fee CHEMISTRY, N° 2551.
l^l The procefs of chymification depends alfo, in a great
Solubility meafure, on the nature of the fubftances employed as
of foods. food, as fome of thefe are much more foluble than
others^ On this fubjeft much information may be de-
*Stark'i rived by confulting the experiments of Dr Stark *, and
Sr r‘ thofe of M. Goffe of Geneva, an abtlraft of which is
given in Johnfon’s Animal Chemiftry, vol. i. p. 207.
From the latter experiments it appears, 1/?, That the fol¬
lowing fubftances are either infoluble, or are not digeft-
ed in the ufual time in the ftomach.
Animal fubjlances* 1. Tendinous parts. 2. Bones.
3. Oily or fatty parts. 4. Indurated white of egg.
Vegetable fubjlances. 1. Oily or emulfive feeds. 2.
ExpreiTed oils of different nuts and kernels. 3. Dried
grapes. 4. Rind of farinaceous fubftances. 5. Pods of
beans and peafe. 6. Skins of ftone fruits. 7. Hulks of
fruits, with grains or feeds. 8. Capfules of fruit, with
grains. 9. Ligneous ftones of fruits. 10. The gaftric
juice does not deftroy the life of fome feeds; hence bit-
ter-fweet, hemp, milletoe, and other plants which fome-
times grow upon trees, are produced by the means of the
excrements of birds, the kernels of feeds being defended
from the menftruum by their exterior covering.
2</, That the following are partly foluble, viz.
Animalfubjlances. 1. Pork dreffed various ways. 2.
Black puddings. 3. Fritters of eggs, fried eggs and
bacon.
Vegetable Subjlances.'— I. Salads of different kinds,
rendered more fo when drefl'ed. 1. White of cabbage
lefs foluble than red. 3. Beet, cardoons, onions, and
leeks. 4. Root of fcurvy-grafs, red and yellow carrots,
fuccory, are more infoluble in the form of falad than
any other way. 5. Pulp of fruit with acids, when not
fluid. 6. Warm bread and fweet paltry, from their pro¬
ducing acidity. 7. Frelh and dry figs. By frying all
thefe fubftances in butter or oil they become ftill lefs
foluble. If they are not diffolved in the ftomach, they
are, however, in the courfe of their paffage through the
inteftines.
3//, That the following are foluble, or eafy of dige-
ftion, being generally reduced to chyme in an hour, or
an hour and a half.
Animal SubJlances.——\. Veal, lamb, and in general
the flefli of young animals, are fooner diffolved than that
of old. 2. Frelh eggs. 3. Cows milk. 4. Perch boil¬
ed with a little fait and parfley. When fried or fea-
foned with oil, wane, and white fauce, it is not fo
foluble.
Vegetable Subjlances.—1. Hferbs, as fpinach, mixed
xvith forrel, are lefs foluble. Celery. Tops of afpara-
gus, hops, and the ornithogalus of the Pyrenees. 2. Bot¬
tom of artichokes. 3. Boiled pulp of fruits, feafoned
with fugar. 4. Pulp or meal of farinaceous feeds.
5. Different forts of wheaten bread, without butter, the
fecond day after baking *, the cruft more fo than the
crumb. Salted bread of Geneva more fo than that of
Paris without fait 5 brown bread in proportion as it
tontains more bran is lefs foluble. 6. Rapes, turnips,
potatoes, parfnips, not too old. 7. Gum arabic, but its
acid is foon felt. The Arabians ufe it as food.
The folvent power of the gartric juice is increafed by
Various ftimulants, efpecially by thofe called condiments,
as fea fait, fpices, muftard, vinegar, as well as by vi-
Vol. XVI. Part II.
489
nous and fpirituous liquors and old cheefe in (mail quan- Of
titics, and by various bitters. It is retarded by large Oigeftion.
quantities of diluting liquors, efpecially when taken ' <l ^
hot j by acids and aftringents taken a thort time after
eating; by uwftuous fubftances j by mental employ¬
ment, or fevere bodily exercife, too loon after a meal)
and by leaning with the breaft againft a table. t ^
It may be proper here to hotice the various opinions Various
that have been entertained refpedting the immediate theories of
caufe of digeltion. The principal of thefe opinions are, ^'6e^‘on'
that it is produced by codtion or heat) by trituration
in the ftomach ) by fermentation, or by putrefaftion. ^
That it is not brought about by heat alone, will ap- Heat,
pear from the circumftance, that many cold-blooded
animals digeft their food as completely, though not fo
expeditioully, as warm-blooded animals,
That it is not effe&ed by trituration in the ftomach Trituration,
alone, is evident from the experiments that have been
made by Spallanzani, Stevens, and others, of giving to
animals food enclofed in hollow perforated balls, fuffi-
ciently ftrong to refift the mufcular power of the fto¬
mach 5 as the balls have been found empty, and not
compreffedk
1 hat it is not owing to fermentation is proved by the FiirniecUU
circumftance, that the more perfeffly digeftion proceeds, tion.
the lefs is the evolution of gafes in the ftomach j the
contrary of which would be the cafe, if digeftion confift-
ed in a fermentation of the aliment.
That it does not depend on putridity, is evidenced by Putndity.
the obfervations that have been made on putrid food
given to dogs, and examined fome time after, when it
was found perfectly fweet.
On the whole it appears, that in moft animals the di¬
geftion of food in the ftomach depends partly on a due
degree of heat, partly on the vital aflion of the ftomach,
but chiefly on the aftion of the gaftric juice.
When the aliments have been converted in the fto- ch/fifica*
mach to the crude pulp called chyme, they are g' a dually tion.
propelled through the pylorus into the duodenum, w here
they are mixed with the bile, the pancreatic juice, and
the fluids that are feparated by the mucous coat of that
inteftine, and are thus reduced to a ftill finer pulp, con¬
taining, as one of its principal ingredients, the nutritious
fluid called chyle, the nature and properties of which,
as they have been but flightly mentioned in the former
parts of this work, fall to be noticed here.
The properties of chyle have not been minutely in- p.0\l*ties
veftigated 5 but according to Fordyce, as far as experi- of chyle?0
ment has been carried, the chyle of quadrupeds is fo
fimilar to that of man, and of each other, as hardly to
be diftinguilhed, even in tribes the moft oppofite to each
other in their ftru&ure, food, and habits of life. As far
as we can perceive, the chyle of a dog or a wolf differs
in nothing from that of a (heep or an ox.
The chyle confifts of three parts j one part which is
fluid, and contained in the lafteals, but coagulates on
extravafation.
The fecond part confifts of a fluid, which is coagu-
lable by heat, and in all its properties hitherto obferved,
it is fimilar to the ferum of the blood.
The third part confifts of globules, w'hich render the
whole white and opake. Thefe globules have been fup-
pofed by many to be an expreffed oil} but this has not
been proved. Neither has it been perfedlly demonftrated
that fugar is contained in the chyle, although it has
3 Q. been
PHYSIOLOGY.
flioii,
*79
Progrefs of
the chyle.
tSo
Paflhge
of food
49°
Of been made very probable The difficulty of determining
'Digcftnru t^efe points aril'es from the fmall quantity that can be col-
v ledted, the larged animals not fupplying more than one
ounce or twOj at the mod. However, the part coagulating
on extravafaiion j the part agreeing with ferum in its
qualities the globular part, which in fome animals,
* Fordyce but not in quadrupeds, exitis without giving whitenefs
on Digs- t0 qle chyle—alone, or along with fugar, form the elTen-
tial parts of the chyle *.
The compound pulpy matter containing the chyle is
carried forward from the duodenum through the whole
courfe of the intedines, where it is fubjefted to the con¬
tinual action of the internal wrinkled membrane of the
bowels, and its nutritious particles, or chyle, felefted
and abforbed by the lacleals that are abundantly didri-
buted there, and open their mouths dire&ly within the
cavity.
As to the movements of the alimentary canal, the
diredtion of hairs found in the domach, and the balls
through the of hairs which are thrown up, would appear to indicate
Juteftines. a circular motion. The imedinal part has a motion
iimiiar to that of a worm, and is called the vermicular
or perijlahic. Here every portion retains its own mo¬
tion, although it be feparated from the red by liga¬
tures. The domach of the polype, the gullets of the
ruminating kinds, and the coeca, have the motion in
different diredlions at different times ”, and that obferved
in the alimentary canal of a loufe is, when viewed
through a microfcope in the time of aftion, amazingly
rapid ; the dimulating caufes employed are the food,
the different liquors with which it is mixed, the air, the
nerves where they exid, and a portion of heat. Some
degree of heat is neceffary to every procefs of digedion,
both in the animal and vegetable kingdom ; what that
degree is depends on the nature of the living body;
and is various according to its age, its health, its em¬
ployments, and habits.
With rjfpeft to the function of digedion in the lower
claffes of animals, we can fay but little. We know that
their food is diffolved in the domachs of the crudacea,
of mollufca, and of polypes \ but whether this procefs
in mod infedls and worms is any thing more than im¬
bibition, or taking in aliment, which is to undergo lit¬
tle change, we are uncertain. We know, indeed, that
many in fecks live on fubdances which mud be diffolved
before they enter into the pores of their bodies, and
that many of them abound in acrid juices, which are
well fitted for this folution. It does not appear that
plants poffel’s what may be called the faculty of di-
gedion.
Relations ^'^e relations between digedion and the funftions we
between di-have already confidered, efpecially fenfation, are various
geftion and and important. The fympathies that exid between the
fenfation. bead and the domach, have been long acknowledged.
Several affeftions of the brain are accompanied with
ficknefs at the domach, lofs of appetite, and indigedion ;
while, on the other band, the deranged date of the di-
gedive organs feldom fails to produce giddinefs, headach,
PHYSIOLOGY.
Of
Di<reftion.
Chap. V.
ringing in the ears, confufion or (depravation of fight,
&.C.; and if the fomier fymptoms arife to a great height,
as in the cafe of o^/erloaded domach or furfeit, coma, Y
or even apoplexy, is frequently produced. In many
nervous adeeHons, particularly hyderia and hypochon-
driafis, in which there frequently takes place altoniffiing
accumulations of air in the domach and Dowels the
affections of the head, fuch as ftupor, confufion of
thought, partial biir.dnefs, &c. fometimes proceed to
fuch a height, as to threaten, or even fomeiimes to pro¬
duce, an apcpkdic paroxyfm. In many cafes thefe affec¬
tions are referred immediately to the head ; but are pro¬
ved, in m -d.indances, to depend on the difordered date
of the alimentary canal, from the immediate relief pro¬
cured by thoie remedies which promote the difeharge
of air, or produce copious evacuation from the bowels.
On the other hand, in feme difeafes, where the head is
primarily affe&ed, as in phrenitis hydrocephalic a (water
in the head^), the complaint is referred to the bowels, from
the codivenefs or other difordered date of thefe. The
daily experience of literary men fhows how much in-
tenfe thought diminidies the digedive powers, and how
iinperfeCfiy dudious occupations can be carried on after
a full meal. The aclion of the digedive organs is alio
confiderably influenced by the mind, or the paffions.
We know how rerffily the appetite may be diminifhed
or dedroyed by fudden anger or affliction.
The action of the domach may even be indue need by
the will. We have known a perfon who could vomit
whenever he pleafed ; and Dr Darwin fpeaks of another
who had acquired this voluntary command over the in¬
verted motions of the domach' and throat, to fuch a de¬
gree, as to gain a fubfidence by exhibiting thefe unna¬
tural powers to the public. At thefe exhibitions he was
accudomed to fwallow a pint of red rough goofeberries,
and a pint of white fmooth ones ; to bring them up in
fmall parcels into his mouth, and redore them feparately
to the fpeCfatcrs, who called for red or white, as they
pleafed, till the whole w^ere redelivered *. * Zcono-
The fympathies that take place between the brain and w,‘1’ vol‘
the digedive organs, are eafily explained, from coniider-P‘ 276'
ing the didribution of the great fympathetic nerve, to p]?te
illudrate which we have given a figure (fig. i.) drew-ccccxvm.
ing its courfe and didribution from the head through the
ched, as far as the domach. i82
The relations between the digedive and the locomo-Relations
tive funftions, are not lefs obvious. Experience fiiewsbetwe.en
how much digedion depends on regular exercife, and aig.eftl°L
how imperfeCfly it is carried on in the domach of the**™ ul0Uv!1'
indolent and fedentary ; while, on the other hand, when
the domach is overloaded, voluntary motion becomes
difficult and fatiguing. Spafmodic contractions of the
mufcles, twitchings of the limbs, and fimilar affeCHons,
are the common attendants of indigedion, though thefe
may perhaps be referred equally to the nervous as to the
mufcular fydem. 1§3
The principal morbid affeCtions of digedion are, nau- Morbid af-
fea, flatulence, eruCtation, rumination (g), vomiting, fe(d'ons
heartburn, diSeftlon*
(g) That ruminating power which is natural to the quadrupeds of the order Pecora, is fometimes met with in
man. We have heard of perfons who regularly brought up their food into the mouth foon after eating, chewed it
over again, fwallowed the juices with the faliva, and fpat out the more folid parts. In thefe cafes, the rumination
is
Chap. VI. P H Y S I
Of heartburn, 'ivater-brafn or pyrq/is, lofs of appetite, and
Abforption. inordinate appetite j for an account of which, fee the ar-
* * *■ tide Medicink.
Chap. VI. Of Abforption.
184
Abforption, We have faid that the chyle is taken up from the
compound pulpy matter compofed of the food and the
animal juices, as it paffes through the inteftines, by the
ladeals. This, however, is not the only abibrption that
takes place in the animal body. The fluids poured out
into cavities by the exhalant arteries, as well as all the fe-
preted or exuding fluids, and even the lolid materials of
the fyftem, are taken up by the lymphatics, and carried
into the circulation the blood poured out into cells in
fome parts, is evidently ahforbed by veins 5 and, as we
(hall endeavour to prove, an abforption takes place over
the external furface of the body.
lS5 What is called the abforbent fyftem, is compofed, in
ri.au>’ j.|ie fUperior animals, of the laAeals, the mefenteric
glands, the thoracic duEt, the lymphatics, and the lym¬
phatic glands. For an account of thefe in man, fee
Anatomy, Part I. Se£t. 14. This fyftem, in a great¬
er or lefs degree, is found in all animals, except fome
mollufca, infefts, worms, and zoophytes. See Cuvier’s
JLefons, tom. iv. le^. xxiii. and Elumenbach’s Cotnpara-
live Anatoiny, chap. xiii.
Bv lafteals The action of the la&eals and lymphatics is probably
and lym- much the fame, and is exerted in a fimilar manner.
phatics. That of the lacfeals is to convey the nouriftiing parts of
the food into the circulating fyrtem •, that of the lym¬
phatics ta carry to the fame fyftem watery fluids, for the
purpofe of diluting the blood, and fuch fluid or folid
materials as ax-e ufelefs, or may prove noxious to the fy¬
ftem. The a£lion of the laTeals may be readily feen on
opening an animal killed two or three hours after eating*,
f '.'d in this way they were firft feen by Afellius. They
are then found filled with a milky fluid, while, at other
times, they are invifible. That the lymphatics are the
principal organs of abforption, is now the general opi¬
nion of all phyfiologifts, though their adfion in this way
can feldom be demonftrated. As, however, it has been
fatisfaclorily proved, that the veins do not in general ab-
forb, and as the lymphatics that proceed from parts that
contain irritating matters, are often-feen inflamed, pi*ov-
ing that they have imbibed a part of the irritating mat¬
ter, there is little doubt that the office of abforption be¬
longs almoft exclufively to the adlion of the lympha¬
tics.
O L O G Y. 49I
Mr John Hunter made feveral experiments to fuew Of
that the veins do not abforb. He conveyed milk, co- Abforption.
loured with various dyeing fubftances, or perfumed with
muflc, into the fmall inteftines of an afs, which was foon gy ti)e
after killed. On opening the veins of the inteftines, and veins,
allowing the blood to ieparate into ferum and craflamen-
tum, the ferum was found neither to be tinged with the
colouring matters, nor fcented by the perfume, while
the coloured milk was evident in the lacfeals. That the
howTever, do in fome cafes perform the office of
abforbents, is evident from the fpeedy depletion of the
corpora cavernofa penis, after having been diftended with
arterious blood ; and from a fimilar depletion that
takes place in the nipple of the female breaft. 1S8
The principal objedt in difpute refpedfing the fundlion % t^e ^n*
of abforption in man and the higher claffes of animals, is,
whether the Ikin poffeffes the power of abforption. This
queftion, as it is both curious and important, wTe {hall
examine pretty much at large ; and for this purpofe we
(hall avail ourfelves of an able paper on the fubjedt, by
Dr George Kellie.
It had long been received as an eftablifhed truth, that
the {kin was an inhaling or an abforbing organ, and
that fometimes the inhalation balanced, or even lurpaf-
fed, the exhalation of the cutaneous furface ; but of late
this dodfrine of inhalation has been called in queftion,
and, in the opinion of many, entirely overlhroxvn. It
has been faid, that this abforption neither does nor can
take place on the outfide of the cuticle ; that in every
cafe of apparent abforption, the epidermis had been in¬
jured, or that the matter abforbed had been mechanical¬
ly forced through it, and brought into immediate con-
tadl with the {kin.
Haller had affexled *, on the authority of Default, * Elementa
that the body acquired an increafe of w'eight in the Pbyjiolo-
warm bath j and this augmentation of weight was^7^’tom•v"
efteemed an experimentum crucis in favour of cutaneous
abforption.
Experiments, however, have fince been made with
every neceffary care, which feem to contradidl the pofi-
tion, and to provd, that the body acquires no additional
weight in the warm bath.
Seguin, from a great many experiments of this de-
feription, concludes, that there is no inhalation, becaufe
the body, fo far from gaining, always loft fome part of
its weight during immerfion, although much lefs than
in the air in equal times f. f La Med,
In other experiments again, as in thofe of Gerard and Eclairee-
Currie, there was no increafe of weight; but the body
3 Q. 2 was
is to be confidered as a difeafe, depending on the inability of the ftomach to propel the folid food into the
duodenum.
Mr Home, in the paper we have already quoted, (N° 161 —169), relates a curious inftance of habitual ru¬
mination in a man 19 years of age, who is blind, and has been an idiot from his birth. He has a very ravenous
appetite, and it is neceffiary to reftrift him in the quantity of his food, fince, if he eats too much, it difordei*s his
bowels. Fluid food does not remain on his ftomach, but comes up again. He fwallows his dinner, which confifts
of a pound and a half of meat and vegetables in two minutes, and in about 1 $ minutes he begins to chew the cud.
Mr Home was once prefent on this occafion. The morfel is brought up from the ftomach with apparently a very
flight effort, and the mufcles of the throat are feen in adtion when it comes into the mouth 5 he chews it three or
four times, and fwalloxvs it j there is then a paufe, and another moriel is brought up. This procefs is continued for
about half an hour, and he appears to be more quiet at that time than at any other. Whether the regurgitation of
the food is voluntary or involuntary, cannot be afeertained, the man being too- deficient in underftanding, to give
any information on the fubjedt.
49 2
P H Y S I
. Y’as not obtcrved to liavc loit any Lhin^ durinji imnier-
Ao urpt:on. £on jn warm bath.
Now, during thefe experiments, the body was doubt-
lefs wafting, by the pulmonary and cutaneous difcharges,
and yet the weight of the body either continued un¬
changed ; or where a lofs of rveight was obferved, this
was conftantly lefs, greatly lefs, than is experienced du¬
ring the fame interval in air. And we might be inclined
to infer, from a truth fo general, and fo well afcertain-
ed, an argument in favour of abforption.
It might be atgued, that the lofs of wreight amounts
to little or nothing, becaufe, during immerfion, the bo¬
dy acquires more by inhalation than it does or can do in
the air j that the lofs by the pulmonary and cutaneous
difcharges is counterbalanced, or nearly counterbalanced,
by the increafed abforption.
Thofe, however, wTho deny abforption, wall not allow
us the advantage of this argument. They tell us, that
the exhalation by the fkin and lungs is diminilhed,
which fufficiently explains why the body lofes lefs in the
warm bath than in air. Eut that the accuftomed dif¬
charges are fuppreffed or diminilhed in the warm or te¬
pid bath, is, we apprehend, far from being proved j
and, till this propofition is made good, the argument
againft cutaneous inhalation cannot be fecurely main¬
tained.
One of Dr Currie’s cafes deferves farther confidera-
tion. We allude to the cafe of dyfphagia, publiftied by
t Medical this gentleman J, in which Mr M. the fubjeft of the
Report, cafe> was feverai t;mes immerfe(l jn a vvarrn bath of
milk and wrater, and was weighed wrhen taken out.
Mr M. it is true, gained no weight w?hile in the warm
bath j but the lofs continually going on. in the air was,
as in other trials, fufpended during the immerfions. Be-
fides, he always exprdTed great comfort from the bath,
with abatement of thirft ; and, fubfequent to the daily
life of it, the urine flowed more plentifully, and became
lefs pungent. An obfervation, precifely fimilar, is made
by Mr Cruicklhank. “ A patient of mine (fays Mr
Cruicklhank), with a ftri&ure of the oefophagus, re¬
ceived nothing, either folid or liquid, into, the ftomach
for two months ; he wras exceedingly thirfty, and com¬
plained of making no water. I ordered him the w^arm
bath for an hour, evening and morning, for a month 5
his thirft vanifhed, and he made water in the fame man¬
ner as when he ufed to drink by the mouth (h) *.
^dbforbents ®Ut t0 return to t^le ca^e ^Currie
J ' himfelf remarks, that the difeharge by urine alone ex¬
ceeded much in weight the wafte of his whole body;
and it cannot be doubted that the difeharge by ftool and
perfpiration exceeded the weight of the clyfters.—Thus
it appears, that the eg c/1 a exceeded the ingejla in a pro¬
portion much greater than the wafte of his body will ex¬
plain. Howr is this accounted for, Dr Currie alks, un-
kfs by cutaneous abforption ?
That the excefs of thefe difcharges above the ingefta
»nd total wafte, can be accounted for by abforption on¬
ly, was indeed an irrefiftible conclufion. Still, how-
fi'rlt edit.
j>- 227.
* Cruik-
OLO GY. Chap. VI,
ever, cutaneous abforption is denied j and, when forced Abforption.
to confefs, that thefe are cafes where the egejla exceed-y-—■*
the ingejla in a much greater proportion than the wafte
ot the body will explain, and which can only be ac¬
counted for by abforption, they refufe this fundion to
the fkin, and beftow it moft liberally, and, in fo far as
we know, moft gratuitoufly, on the lungs. We are
not entitled, in return, to deny the reality of pulmonary
abforption, but we may furely be allowed to urge, that
there is no proof that the only inhaling organ is in the
lungs j and there is none agaiuft the poffibility of cuta^
neous abforption.
Is it not, on the other hand, proved, by the experiments
of Seguin and Lavoifier, that the exhalation, greatly ex¬
ceeds the abforption by the pulmonary fyftem ? And if
this is always the cafe, we cannot explain by pulmonary
inhalation alone, why the egejla ftiould, in fome cafes,
exceed the ingejla in a much greater proportion than the
wafte of the body will account for.
We now proceed to examine another clafs of experi¬
ments, much infilled on by thofe who deny cutaneous
abforption j we mean thofe experiments performed by
immerfing a part of the body in folutions of active drugs,
the abforption of which Ihould be indicated by their ufual
effects on the fyftem.
Seguin made numerous experiments of this kind, with
folutions of muriate of mercury (corrofive fublimate), on
fyphilitic patients. And we are informed, that in cafes
where the epidermis was perfectly found, neither the
known effects of mercury on the body, nor any amelio¬
ration of the venereal fymptoms, was ever obferved.
He alfo immerfed his own arm in a folution of two drams
of the mercurial muriate in ten pounds of water. At the
temperature of io° and 28° Reaumur, no part of the fait
was miffing at the end of the experiment; but when the
bath was at 180 of the fame fcale, there was a lofs of one
or two grains, of the muriate in the hour, though the
quantity of fluid was not diminilhed.
The explanation given by Seguin of this unexpected
refult is curioully ingenious, but embarraffed, and incoi>*
fiftent.
At the temperature of 120, he obferves, the exhalants
are in a ftate of contraction, and their orifices nearly clof-
ed. When the heat again is raifed to 26°, the exhala¬
tion is fo rapid, that nothing can enter the veffels from
without 5 but at 18° of temperature, the orifices of the
exhalants are fufficiently relaxed, and the exhalation at
the fame time fo conveniently languid, that the folution-
refts quietly in contaft with the matter of perfpiration
in the mouths of the exhalants, where it is fomehow or
other decompofed j a part of the fait leaving the water
of folution, and combining with the perfpirative matter,
with .which it is carried into the fyftem *. Carried into* La
the circulation by the exhalants ! Is not this a plain ac- EciairePy
knowledgment of the reality of inhalation ? But if intom*iiL
one cafe fubftances may thus be carried into the circula-P*
tion, why not in many others ?
Surely if the weight continues undiminiffitd, in cir-
cumftances
(h) That thirft may be allayed by immerfion in water, is fully proved by the experience of Ihipwrecked mari¬
ners. who, when obliged to take to their boats with very little frefli water, frequently have recourfe to bathing im
*he fea, or covering themfelves with a ftftrt wetted in fait water, and thus quench their thirft, nearly as well as, if
they had drunk frelh watet;.
f Ralio
Medendi,
part iv^
chap. 3.
$ Eiem.
PbyfioL
tons. v.
P- 90.
Chap. VI. P H Y S I
Of cumilances where the body js continually lofing, we may
Abfurptioiu infer> that fomething has been gained by abforption.
v ' And where the egefta exceed the ingeila in a proportion
much greater than the wafte of the body wall explain,
there abfortion muft have been going on.
The cafe of Mr M , publilhed by Dr Currie, is
not lingular. The writings of phylicians abound in li-
milar examples. They had often occurred to that ex¬
cellent clinical practitioner De Haen, who was there¬
fore perfuaded that water was imbibed f. Haller too,
with his ufual induftry, has collefted a great many ob-
fervations of the fame kind J.
Again, when phyficians were engaged in their ex-
tenlive ftatical experiments, weighing themfelves, their
ingejla and egejiay for many months, nay for years to¬
gether •, they fometimes obferved, that fo far from loling,
they had gained weight, efpecially during cold and moift
weather. Thus, Rye, under a cold and humid atmo-
fphere, gained 13 ounces. Linnings, during two hours
expofure to cold, acquired 84- ounces. The abbe Fon¬
tana, after two hours expofure to a moift atmofphere, re¬
turned home fome ounces heavier than he went out. De
Gorter gained 6 ounces in one night j and on other
occafions, two ounces and four ounces. Thefe obferva-
tions are confirmed alfo by the experience of Dr Francis
Home, profeflbr of Materia Medica in the univerfity of
Edinburgh. ‘ Having fatigued myfelf pretty much (fays
he) in the afternoon, I went to bed without fupper, and
was fo hungry that I could not fall afleep for fome time.
Betwixt eleven at night and feven next morning I had
$ Medical gained two ounces J.’
TraHc and Here then are examples of the body gaining confider-
ably more than the ingejla will account for, acquiring
weight when neither food nor drink had been fwallow-
ed. And we have the concurring teftimony of the moft
refpe&able writers fupporting the fame truth.
How can this increafe of weight be accou»ted for,
unlefs by abforption ? In fuch experiments, the lofs of
weight, which cannot be accounted for by the fenfible
egejla, is attributed to the exhalation ; the increafed
weight fometimes obferved, and which cannot be ex¬
plained by the fenfible ingejla, muft in like manner be
referred to the inhalation.
That the fyftem may be affefted by aftive medicines
introduced and abforbed by the Ikin, cannot be denied.
And were proofs rtill wanting to eftabliih the doftrine of
cutaneous abforption, this argument might be infilled on.
It is true, that friflion is commonly employed when w7e
wilh to introduce medicines by the Ikin, by which, it is
faid, the fubftance is mechanically forced through the cu¬
ticle, and brought into conta<51 wdth the abforbents of the
true Ikin. The fyrtem, however, may be affefled without
friction, for example, by wearing a mercurial plaiter, and
more certainly by mercurial fumigation, as pra&ifed by
Lalonette and others *.
It might even be concluded from an examination of
voTl'pasT ^ie ftru<^ure the 1km, that abforption muft take place
at its furface. We know that the cuticle is porous, and
is penetrated by exhaling veffels *, we know that lymph¬
atics commence immediately below it ; and we know
that when certain fubftances are applied to the cuticle,
efpecially when this application is aided by moderate
friftion, as in the cafe of applying garlic poultices to the
feet, and the more familiar inftance of mercurial inunction,
Exper.
p. 250.
• Edinb.
ATed. and
O L O G Y. 49S
that thefe fubftances are taken up by the abforbents, and Of
conveyed into the circulation. Abforption.-
From a confideration of all thefe circumftances, we
think it fully proved, that the Ikin is an abforbing or
inhaling organ. For further proofs we may refer our
readers to Bichat’s Anat. Gener. tom. iv. p. 691. 189
Mr Charles Darwun, fon of the late Dr Darwin, pub- Suppcfed
lilhed in 1780, a Latin thefis, wdiich is tranilated in theret™£rac:2'
29th fedt. of his father’s Zoonomia, vol. i. in which he at-
tempts to prove, that the valves of the lymphatics are fophatks.
formed as in particular cafes to admit of the regurgitation
of the abforbed fluids. The arguments on Which he
founds this opinion (befide the difficulty of accounting
for the phenomena of feveral difeafes on any other prin¬
ciple), are chiefly the following :
Firft, The mouths of the lymphatics feem to allow wTa-
ter to pafs through them after death, the inverted way,
more eafily than in the natural diredtion.
Secondly, In fome difeafes, as diabetes and fcrofula, it is
probable the valves themfelves are difeafed, and are thence
incapable of preventing the return of the fluids they fhouid
fupport.
Thirdly, There are valves in other parts of the body'ana-
logous to thofe of the abforbent fyftem, which are liable,
when difeafed, to regurgitate their contents.
Fourthly, The capillary veflels, which muft be confider-
ed as analogous to abforbents, may be feen, in animals
fubmitted to the microfcope, to regurgitate their contents
into the arteries, during the ftruggles of the dying ani¬
mal.
By means of this hypothefis (for notwdthftanding the
arguments adduced in its favour, wTe can call it no bet¬
ter), Mr Darwin explained the fpeedy paflage of wa¬
tery fluids from the ftomach to the urinary bladder; the
phenomena of diabetes •, diarrhoea, dropfy, cold fweats j
tranflations of matter, chyle, milk, and urine j the ope¬
ration of external remedies, &c. r9o-
In all thofe clalTes of animals that poffefs a complete Abforptiou'
abforbent fyftem, the phenomena of abforption feem
proceed much in the fame manner as in man 5 but in ( f aCmmais-
fome of the inferior animals, efpecially in mollufca and
wmrms this fun&ion feems to be performed by the veins *. * Cuvier
In \}c\t echinodermata, however, efpecially in the fea-ur-
chin ( echinus efculentus'), lymphatics have been demon-tom'1V*
ftrated by the fecond Monro. In infedts and polypes therel6l‘
is no proper abforption. I9I
The abforbing veflels of plants are chiefly the fibrils Ybforptlon-
of the roots, which evidently imbibe moifture, and per-°f P'auts*
haps gafeous fluids, from the earth j but there have alfo
been demonftrated veflels opening beneath the outer bark,
which botanical phyfiologifts confider as lymphatics.
“ Lymphatic veflels (fays Wildenow), are found in the
epidermis of plants, and are of great minutenefs, ana-
ftbmofing in various w-ays through fmall intermediate
branches.” They furround the apertures of the cuticle,
by which the inhalation and exhalation of vegetables are
carried on ; but they are fo minute as not to have yet
been filled with coloured liquids. Round each opening,
which is commonly fhut by a moveable valve, they foim
a circle, rarely a rhombus, as in the %ea mays. In the
/ilium splcedonicum, thofe veflels run obliquely, and fome- Plate
what in an irregular undulating manner, fig. 2. In the ccccxvrri. -
common onion {allium cepd), they run in a ftraight,
though oblique and regular form, fig. 3. In the pink,
{dianthus
♦
494
P H Y S I O L O G ^
Of
* Wilde-
now's
Princ. of
Bot. feci.
230.
192
{clianthus caryaphyilus'), they are very ftraight, with
A'.norpuon. ancj horizontally tranfverfe branches, fig. 4. In
almoft every plant they have their certain and peculiar
direction, which in each remains conflantly the fame *.
The theory of abforption is ftill but imperfedlly un-
derftood. We fliall briefly notice the principal hypo-
thefes that have been brought forward to account for the
Theory of entrance of fubftances into the mouths of the abforbing
abforption. veffels; for this part of the procefs alone feems to be dif-
puted.
It was long the opinion of phyfiologifts, that fluids
enter The mouths of the abforbents on the principle of
capillary attradiion ; but as the abforbing veffels are not
circumftanced like rigid capillary tubes, immerfed in a
fluid ; and as, were this hypotheffs juft, abforption fhould
go on with regularity, and all fluids fhould be abforbed
indifcriminately, neither of which circumftances is true $
this hypothelis is now generally abandoned.
Mr John Hunter accounted for the entrance of fub¬
ftances into the mouths of the abforbents, by attributing
to the mouths of thefe veflels a power of nibbling, fimi-
lar to that exerted by a caterpillar when feeding on a
leaf. This opinion may be called ingenious, but is cer¬
tainly very wild and fanciful.
Dr Fullarton, in a thefts on abforption, publifhed at
Glafgow in 1800, attributes to the abforbing orifices, a
power of fuel ion fimilar to that of the probofeis of but¬
terflies, and the tentacula of fome marine animals.
The firft and third of thefe hypothefes fuppofe the ab-
forbents incapable of taking up any but fluid fubftances;
but we well know that even the hardeft bones are fome-
how abforbed, and conveyed to the circulation. We
muft therefore add another hypothefis, which fuppofes
that there is fecreted in the animal body, a fluid capable
f Duncan's of diffolving flefli and bones f. The hypothefis, however,
is without foundation. It is contrary to the fimplicity
of the animal economy, that there fhould take place, firft,
a fecretion of iolid matters to compofe the ftrufture of
the body, and then a fecond fecretion to diffolve them.
We muft therefore confider this part of phyfiology as a
fubjedl of future inveftigation.
When the abforbed fubftances have once paffed the
barrier of the firft valve, it is not difficult to account for
their further progrefs through the lymphatics. A con¬
tinual fucceffion of frefli abforbed matter muft drive for¬
ward what is already in the veffels, while the valves muft
in general prevent its reflux. The impelling force from
behind is alfo probably afiifted by the irritability of the
veffels. It is not fo eafy to decide how the abforbed
matters pafs through the glands, if, as is generally be¬
lieved, they do not in thefe form continuous tubes, there
muft be a freih abforption by the mouths of the veffels
that pafs out of the gland, which is as difficult to account
for as the firft reception at the origin of the veffels.
Relations of The relations that take place between abforption and
akforpuon the preceding fundlions, are perhaps the lead underftoed
of any that occur in the animal economy. We know
that the adlion of the abforbents is greatly affifted by
mufcular motion, and that it is in general moft defedlive
in indolent and fedentary perfons. An evident fympa-
thy is alfo obferved between the ftomach and the ab¬
forbents. Naufea, and efpecially vomiting, are power¬
ful promoters of abrorption, and fotne remarkable in-
ftanccs are related of the fpeedy abforption of a large
Chap. vn.
JVIed. Com
vol. x.
P- 3 54'
103
with the
preceding
tundlions.
quantity of purulent matter from an abfc'eft, in confe- Of
quence of violent vomiting. Circulation.
Chap. VII. OJ Circulation.
194
We have traced the nutritious particles of the food Circulation,
from the inteftines through the lacleals, the mefenteric
glands, and the thoracic duct, into the left fubclavian
vein, where we find the chyle is mixed with the venous
blood, and carried to the right auricle of the heart. We
muft now confider how the tluids are conveyed to every
part of the body, or we muft examine the funclion of cir¬
culation.
This function takes place in all the vertebral animals, Organs,
and in mollufca, worms, and cruftacea ; but there appears
to be no real circulation in infects, zoophytes, and plants.
The organs by which circulation is performed differ
effentially in the feveral clafies of animals. Thofe of
the human fyftem have been deferibed in the firft part of
Anatomy, fed. x. and xi. and a brief comparative
view of thefe organs in the inferior animals, has been
given in the lecond part of that article, N° 154, 201 
204, 300, &c. .and in the articles Cetology, Erpeto-
logy, Ichthyology, and Ornithology. For a fuller
account of thefe latter, we may refer to Cuvier’s Logons,
lee;, xxiv and xxv. and to the Comparative Anatomy of
Elumenbach, chap. xii.
It is well known that, in the red-blooded animals, thepuimonic
blood is not of the fame ffiade of red in every part of the and fyfte-
body ; but that what has paffed through the lungs, and mic Parts*
is circulating through the arteries that proceed from the
aorta, is of a fiorid red colour, while that which is fent
to the lungs by the pulmonary artery, as well as that
which is returning from the extremities of the arteries
through the veins, is of a purple or crimfon colour. As
one fet of organs always contains florid, and another fet
always erimfon blood, it is convenient to diftinguifti each
fet by an appropriate name. Dr Barclay has done this,
and he calls that fet of organs which are employed to
convey the blood from the arteries, and diftributed to
the lungs, pulmonic, compriling the pulmonic veins, viz.
the vena cava and its branches, pulmonic auricle, pul¬
monic ventricle, and pulmonic arteries: while he denomi¬
nates that fet of organs which return the blood from the
lungs, and diftribute it to the fyftem, fijjlemic, compre¬
hending the fyftemic veins (pulmonary veins), fyftemic
auricle, fyftemic ventricle, and fyftemic arteries, (the
aorta and its ramifications). One great advantage of
this nomenclature, is that it prevents the ambiguity of
the expreffiows right and left, anterior and poferior, ap¬
plied to the auricles and ventricles of the heart. We
fhall therefore employ them in the fubiequent part of this
chapter *. * See Bar-
For an account of the nature and properties of therlfr’l1
blood, fee Anatomy, Part I. fe<ft. 14. and Chemistry,"Motiwu
N°. 2642. _ _ P, 231. ’
It may not be improper, in this chapter, to notice the I97
principal arguments that have been ufed to prove the ^roofs °9
circulation of the blood. They are as follow : tiiedrcn «-
I. When an artery is tied, the part 01 the artery that blood,
is betwixt the ligament and the heart, fvvells ; but that
part of it which is betwixt the ligature and the remote
branches, becomes more flaccid than before. On the
’other hand, when a vein is tied, the part between the li¬
gature
Chap. VII.
. gature and tlie remote branches, fwells, while the part
Cr cuiation. between the ligature and the heart becomes flaccid.
2. The valves placed at the mouths of the aorta and
pulmonary artery, mult prevent the blood frcm regur¬
gitating into the ventricles, while they permit it to flow
forward through the arteries, into the capillary branches
oi: the veins. Again, the valves fitualed in the courfe
of the veins prevent the blood from flowing back into
the arteries, while they permit it to proceed forward-
through the venous trunks into the heart.
3. By the afliftance of a micrcfcope, the blood may
be leen in the pellucid parts of animals, as the feet of
frogs, (lowing from the arteries into the veins.
4. When an artery of moderate fize is wounded, and
not fecured by ligature or compreflion in proper time,
the blood (lows out till the animal be dead.
5. Any thin liquid, when injected into an artery, does
not pafs backwards into the heart, but flows forward in¬
to the inoiculating veins. On the other hand, f’uch a
liquid thrown into a vein, flows towards the heart, and
not into the imaller branches of the vein.
The phenomena of circulation in the human body have
been already mentioned under Anatomy, fe<ft. xii. and
xiii. and under Medicine, N° 95. We fhall here only
offer a compendious view of the courfe of the blood in
I55 the adult and in the foetal date.
Circulation T After birth, the blood coming from every part of
in the adult the body through the numerous ramifications of the ve-
i31.111, na cava, is poured into the right or pulmonic auricle of
the heart, by the contradlion of which it is thrown into
the right or pulmonic ventricle, which contracting,
throws it into the pulmonary artery, being prevented
from regurgitating into the auricle by the adtion of the
tricufpid valves. It is now, by means of the ramifications
of the pulmonary artery, diltributed through the lungs,
from which it is brought back by four principal pulmon¬
ary veins, and poured into the left or fyftemic ventricle,
which contradtipg with great force, propels it into the
aorta, it being prevented from regurgitating into the au¬
ricle by the adlion of the mitral valves. The blood be¬
ing propelled into the aorta, is by its trunks and branches,
diltributed to every part of the body, and brought back
as before by the ramifications and trunks of the ve/ia
cava.
199 _ II. In the foetal date, the blood being brought back
iii'die hT" k°m every Part °* t^ie body by the ramifications and
raan foetus. trunks of the vena cava, is poured into the pulmonic
auricle of the heart, where it is mixed with the blood
brought from the placenta. A part of this blood is con¬
veyed from the firms of the auricle while in a date of di¬
latation, through the oval hole, into the fydemic auricle j
while another part, by the contradlion of the auricle, is
thrown into the pulmonic ventricle, which contradling,
propels it into the root of the pulmonary artery. From
this the greater part of the blood pafles through the ar-
terious canal, that in the foetus joins the pulmonary ar¬
tery to the aorta, into this latter j while the remainder is
didributed by the ramifications of the pulmonary artery
to the lungs, and brought back by the pulmonary veins
to the fydemic auricle of the heart. By the contradlion
of this auricle, the blood is thrown into the fydemic ven¬
tricle, which contradling, propels it into the aorta. Now,
while one part of the blood is didributed by the numer¬
ous ramifications of the aorta to every part of. the body
■ 495
of the foetus, another part is carried from the miernal rr'
iliac arteries, through the two umbilical arteries, into Cirndauo!-.
the placenta, from which it is conveyed through the
umbilical vein to the linus of the liver. Hence, one part
ot the blood, without entering the liver, is tranfmdted
by a branch of the umbilical vein, called venous dutf, in¬
to the left branch oi the vena cava hepatic a ; thence in¬
to the inferior great vena cava 5 while another part, by
another branch of the umbilical vein, (lows into the left
branch of the vena porta, by the numerous ramifications
of which it is diilributed to the liver. From the liver
it is carried by the vence cavee hepaticce into the inferior
great vena cava, ■whence it is conveyed with the red of
the blood, to the pulmopic auricle of the heart, to be
didributed as before.
\V e mud now briefly confider the powers by which Powers car-
the blood is made to circulate through fuch a multitude vying on the
of veffels, fo infinitely ramified, and^ differing fo much circulation,
in their diameter. It feems generally allowed at the
prefent day, that thefe powers are chiefiy the immediate
mufcular action of the heart, the action of the arteries,
the valves of the veins, and the preffure produced on
fome of the veins by the action of the muicles that lie
contiguous to them.
1. That the heart mud poffefs very confiderable force a A on of
in propelling the blood through the arteries, may be the heart,
fuppofed from the great mufcularity of its ventricles
and this force has been proved by experiment and ob-
fervation. From experiments made by Hales, viz. that
or inlerting a glafs tube into a large artery, and rneafur-
ing the height to which the blood afeends at each pul-
fation, it has been calculated, that the human carotid
aiteiy is capable of projedlmg its blood to a perpendicu¬
lar height of feven feet and a half 5 and if we'edimate
the furface of the fydemic ventricle at 15 fquare inches,
we fhall find that it fudains a preffure of 1350 cubic
inches, equal to 51 pounds weight, which it has to
overcome by its con trading force *. This is a moderate * „ , r,
computation ©f the force of the heart, for Borelli edi- Statical
mates it at 180,000 pounds, while Keill diminifhes it Efays,
to eight ounces. Senac again, from having obferved,vo!-
that if a weight of 5c pounds be attached to the foot’
with the knee of that fide placed over the oppofite
knee, the weight will be railed at each puliation, and
allowing for the didance at w hich the weight is placed
from the centre of motion, computes the force of the
heart at 400 pounds f. Blumenbach has leen the blood + Trai^
projeefed from the carotid of an adult more than fivedn Cceur’
feet J. On a medium calculation, edimating the quan-1 hnptv-
tity of blood contained in the body at 30 pounds, the tiones
number of pulfations in each minute at 75, and the^°^'
quantity of blood ejefted from the fydemic ventricle at
each contraftion at twTo ounces and a half, w’e lhall find
that the whole 30 pounds of blood will be carried
through the whole body no lefs than 23 times in an
hour, or the circulation wall be completed in lefs than
three minutes. . From thefe circumdances w^e mud infer
that the impelling power of the heart is very great, and
fully adequate to the office which it has to perform.
Various hypothefes have been formed to explain how
the heart and arteries are excited to motion, but our li¬
mits will not permit us to detail them. Our readers
will find them related at confiderable length, and fully
examined in the Pain apes de Phyfioiogie of Dumas, tom..
ilk.
PHYSIOLOGY.
49 6
Of
Circulation.
* TJvnter
on the
blond,
p. 114.
203
Valvular
flrudtureof
the veins.
204
A&iur. of
'the mufcles,
205
Circulation
of the infe¬
rior ani¬
mals.
206
Circulation
of the moi-
lufca.
207
in the
vermes;
2c8
in crulta-
*ca.
lii. p. 332—354. The general opinion at prefent en¬
tertained on this fubjedl is, that the heart is excited to
action by the liimulus of the blood.
2. Although it is more than probable that the a£Hon
of the heart is the principal inftrunjent in carrying on
the circulation, there can be no doubt that the arteries
contribute effentially to this office. They are evidently
mufcular, and are poffeffed of confiderable irritability j
are lupplied with numerous nervous filaments, and are
nouriffied by fmall arterial branches, commonly called
vaja vaforum. Nay, we know that they are fufceptible
of contraftion; for wffien we divide an artery in the liv¬
ing body, the divided extremities gradually contraft,
till, if the animal is not killed by the experiment, the
aperture is at length obliterated LalUy, there have
been inltances of fcetufes without a heart; and as wre
muft fuppofe that, during the life of the foetus, the cir¬
culation was going on, it is a natural inference that this
was chiefly efte&ed by the contraftion of the arteries,
and not entirely by the impelling power of the circulat¬
ing fyftem of the mother,
3. It cannot be fuppofed that the veins have any im¬
mediate aftion on the blood, as they exhibit no circular
fibres like the arteries, except in the immediate vicinity
of the heart j but their valvular ftrudlure mull; contri¬
bute to the carrying on of the circulation, from the op-
pofition it gives to the return of the blood, fo that what
is called the vis a tergo, or impelling power from be¬
hind, aided by the conical form of the veins, may have
its full effect.
4. That the a£Hon of the mufcles has confiderable in¬
fluence in propelling the blood towards the heart, in
thofe veins that lie in their neighbourhood, is evident
from the effefl that bodily exercife produces in accele¬
rating the circulation, and from the efficacy of friftion
in removing congeftions of blood in the veins of the ex¬
tremities, and in the more familiar inftance of promot¬
ing the fwelling of the veins of the arm by the fame
means in the operation of bleeding.
The circulation in thofe animals whofe ftrufture ap¬
proaches to that of man, differs little from what is above
deferibed. There are indeed fome peculiarities, a few
of which we fhall prefently notice. An account of the
circulation in the cetacea wflll be found in the article
Cetology, N° 140—145, that of the reptiles is de¬
feribed under Erpetology, page 309.
The mollufca poffefs an evident and powerful circula¬
tion. Moft of them have a Ample heart, sonfifting of
one auricle and one ventricle; and in thefe the vena cava
performs the office of an artery, carrying the returning
blood to the gills, whence it paffes to the auricle, and
is afterwards thrown into the aorta. There is a pecu¬
liarity in the cuttle fiffi, which has a heart confifting of
three ventricles, without any part that can properly be
called an auricle. Two of the ventricles are placed at
the roots of the two bronchiae, and have each a branch
of the vena cava, by wffiich they receive the blood from
the body, and propel it into the bronchise. The re¬
turning veins open into the middle ventricle, and from
this the aorta proceeds.
Some of the vermes, as the leech, and the tribes of
the naias, nereis, and aphrodite?, and fome fpecies of
lumbricus, have no heart, but they have circulating vef-
fels with evident contraftion and dilatation.
In the crujiacea, the circulation is performed by a
4
PHYSIOLOGY. Chap. Vlf.
Angle ventricle, expelling the blood into the arteries of
°f
the body, and receiving it again after it has palled Circulation,
through the gills, in a manner very fimilar to the circu-
lation of fiffies. 205>
There is no circulation in infe&s ; but thefe animals Contraft-
have running along the back a membranous tube, in'nSanddi-
which alternate contractions and dilatations are Percep-
ceptible. This tube, however, is doled at both ends,
and has no vellels proceeding from it. aro
From the refearches which evince circulation to be a No circula-
funCtion fo general among animals, fome are difpofed totion in
think it takes place in all living bodies. But notwitk-l?*ant5*
Handing the falhionable language of circulating fluids,
of veins, arteries, and even of valves, in the vegetable
ftruCture; yet nothing performing the office of a heart,
and nothing that feems to condud fluids in a circular
courfe, has been found in plants. In the vegetable
kingdom, the chyle is diftributed to all the parts, from
the numerous veffels which convey the lap; and thefe
veffels, being fitted by their ftruCture to carry the fap
either downwards or upwards, from the branches to the
roots, or from the roots to the branches, is the reafon
why plants inverted in the ground will fend forth roots
from the place of their branches, and fend forth branches
from the place of their roots. Even a fimilar diftribu-
tion of the chyle takes place in fome animals. In the nor in fome
human tjenia, in the fafciola hepatica (fluke) of ffieep, animal!*
and in moft polypes, the chyle, without a circulating
fyftem, is conveyed direftly to the different parts from
the alimentary canal.
For an account of the motion of fap in plants, Fee
Darwin’s Phyto/ogia, a paper by Mr Knight in the
Philofophical Trarifa&ions for 1801, Wildenow’s Prin¬
ciples of Botany, feft. 276, and the article Plant in
this Encyclopaedia.
The relations that fubfift between the fundlion of cir¬
culation, and thofe which we have already confidered,between
are very important. We ffiall begin with thofe of cir-cireulatio®
culation and fenfation. That the funftions of the ner-^ ^en^a-
vous fyftem muft be confiderably influenced by the cir-tlonk
culation of the blood, may be fuppofed a priori, from
the large quantity of blood fent to the head, this being,
on a moderate calculation, about one-tenth of the whole.
A certain quantity of blood In the veffels of the brain
feems effential to the due performance of the fun ft ions
of that organ ; and thofe animals, which, like man,
have the blood fent in greatefl: quantity, and with great-
eft impulfe, feem to poffefs the faculties of the brain in
the greateft perfeftion, while thofe in whom the mo¬
tions of the blood towards the head is much retarded,
as in the flieep and cow, are remarkable for mildnefs
and ftupidity. When, however, the quantity of blood
becomes too great, or its impetus too violent, the facul¬
ties of the brain are impaired, or altogether deftroyed*
No man, and very few other animals, can remain fuf-
pended with the head downwards for any long time,
without dangerous, and commonly fatal confequences.
The bat, indeed, is a remarkable exception to this rule,
for this animal can hang by its hinder feet for days or
weeks together, with perfeft fafety, a circumftance that
may be accounted for from the very fmall quantity of
blood contained in its circulating veffels. Again, the
brain exerts an evident influence on the circulation. It
is well known how much the aftion of the heart and ar¬
teries is quickened, impeded, or rendered irregular, by
the
art
"Relations
ch.iP. vir.
P H Y S I
Of _ the paffions of the mind. Cafes are recorded in which
Circulation. thefe_paffi0nS, carried to excels, have altogether flopped
’ v ” the circulation, and produced inflant death. Fainting
is often brought on by the fight of a difgufling or terri¬
fying objeft, or by the odour of perfumes, or of fub-
Itances to which the perfon has a particular antipathy.
The fympathy between the heart and the nervous ly-
flem is farther ftiown by the violent pain below the
Jlermm, and fometimes in the arrn, in cafes of organic
dileafe of the heart.
The circulation is even affe&ed by intenfe thought ;
and we have heard of a bleeding from the nofe being
brought on by long and deep ftudy, while the body was
213 in a reclining pollute, namely in bed.
Relations 'J'he fundtions of circulation and motion are intimate-
ciicuhnion ^ 1S fcarcely necelfary to notice the accele-
and motion. rati°n of the pulfe, in confequence of exercife and la¬
bour, or to remark that in indolent and fedentary people
the circulation is generally flow and languid. In gene¬
ral, too, the blood circulates with moft rapidity in thofe
animals who are formed for quick motion, though the
Inflance above quoted, of the bat, fliows that the quick-
nefs of motion does not depend on the quantity of blood.
Several curious anatomical fadls have rendered it proba¬
ble, that the produdlion of quick or flow motion depends
in a great meafure on the mode in which the arterial
branches are diftributed to the moving organs. The
arterial branches that fupply the organs of voluntary
motion, are divided in iuch a manner as to impede the
motion of the blood towards thefe organs as little as pof-
fible : their ramifications are therefore few, and they go
off from the trunk at very acute angles ; wfliereas thofe
that fupply the vifcera are at nearly right angles, are
often tortuous, and are otherwife fb conftrufted as fre¬
quently to impede the flow of blood. Pbyfiolcgifts have
even explained the greater power that is generally found
in the right arm, and the greater readinefs with which
moft people ufe that arm, by the manner in which the
right fubclavian artery comes off from the aorta. This
indeed we are difpofed to confider as fanciful, and to
attribute the more ready ufe of the right arm folely to
2T4 habit and early inftmclion not to employ the left.
Diftribu- In fome animals that are remarkable for flownefs of
tion of the motion, as the lemur tardigradvs, or flow lemur, and
tbeTmbTof ^bradypus tridattylus, or common floth, there is a
flow-mov- curious conftrudlion of the arteries that are diftributed
ing ani- to the limbs of thefe flow-moving animals, which mull
mals. have the effebl of breaking the force, and impeding the
velocity of the blood towards thefe limbs. In the lemur
tardigrade, a fpecimen of which was differed by Mr
Carlifle, it was found that the fubclavian artery and the
external iliac were, foon after rifing from the general
trunk, divided into a great number of equal-fized cylin¬
ders furrounding -the principal artery, now diminilhed
to a very fmall fize, and that each of thefe branches
was lent to each of the principal mufcles of the limbs,
wftile the other arteries that fupplied the other parts of
the limbs wTere divided in the ufual arborefcent form.
Struck with this appearance, Dr Shaw and Mr Carlifle
afterwards examined feveral fpecimens of the floth, and
found a fimilar conformation, while in other fpecies of
, bradypus, not remarkable for flow' motion, no fuch ap-
Geneml' Peara,?ce took p\ace * Fig. 5. & 6. Plate CCCCXVIII.
Zoology, rePreient the divifion of the arteries in the flow lemur
vok i. above'defcribed.
Vol. XVI. Part II.
O L O G Y. 4g7
The relations between the circulating and digeftive Of
organs are proved by thefudden acceleration of the pulfe circulat;on
from ftimuli received into the ftomach ; from the dimi- ' " 'r*‘ ‘
nilhed circulation or flidden ceffation of the heart’s mo- Relations
tion from powerful fedatives received into the fame or-of circula-
gan, efpecially the prunus lauro-cerafus ; from the irre-tijn wilh
gularity produced in the circulation in confequence 0fdlgeftl0n*
dyfpepfid, and many other confiderations. 216
I hat there is an intimate relation between circulation Relation of
and abforption, cannot be doubted, though the naturecircuIatiotl
and eftedls of this relation are not yet well underftood. a"d al^orP-
W'e know that the veffels fympathize with the abfor-101'
bents in their aflivity or languor ; that tvhen the abfor-
bents arc languid in their adiion, the blood-veffels, ef¬
pecially the exhalants, are in a feeble or relaxed ftate,
and that the abforbents are often roufed to greater ac-
tionby remedies that firft a 61 on the circulation. 2I7
Numerous experiments have ihown how much theAcftionof
colour and confiftence of the blood are altered by thefhe xeflels
mere action of the vefl'els; and this difcovery has ena- °" 1
bled us to conjecture with more probability than w e did IjUJ0U'
formerly, wny in infants and phlegmatic perfons the
blood is paler, in the choleric more yellow, and in the
fanguine of vermilion red. It explains likewife in fome
meafure, why the blood varies in the fame individual,
not only with regard to the ftate of health, but likewife
at the lame inftant 5 and why the blood wfluch circulates
through the veins has not the fame intenfity of colour,
nor the fame confiftence, as that of the arteries j and why
the blood wflrich flows through the organs of the breaft
differs from that which paffes languidly through the vif-
ccra of the lower belly. This power of the veffels over
the blood wflll bring us alfo to the true caufe why the
veffels vary in the denfity of their coats and in their dia¬
meters 5 w7hy they are lometimes convoluted in a gland,
and why they fometimes depofit their contents in a fol¬
licle ; wfey they are fometimes of a fpiral form ; why
the branches ftrike off at various angles \ why they are
varioufly anaftomofed ; why they fometimes carry the
blood with difpatch, and fometimes flowly through a
thoufand windings. Ey thefe means their a6tion is va¬
ried, and the blood prepared numerous ways to anfwer
the ends of nutrition and fecretion.
On the varieties of the pulfe, and the morbid affec¬
tions ol circulation, fee Medicine, N° 96—104.
Chap. VIII. OfRefpiration.
While the fluids are palling through the body, byNeceffity
wdiat is called the greater circulation, they give out cer- of refpira-
tain parts or principles, partly for the purpofe of nutri-tion*
tion, and partly to free the fyftem from noxious mat¬
ters. In order to regain fome of the principles wdrich
they have loft, it is neceffary that they Ihould be expof-
ed to the influence of atmofpheric air ; for wfeich pur-
pofe they are made to pafs through appropriate organs,
which, as wre have already obferved, are in general ei¬
ther lungs or gills. The adlion by which the fluids and
the air are made to a6l on each other, is called refpira-
fton, and confifts of twro kinds, infpiration, by which the
air is received into the body, and expiration, by which
it is again throwm out.
So effential is refpiration to the fyftem, that fnails,
chameleons, and fome other animals, can live for years,
without any apparent nourifhment, provided they be not
3 ft excluded
498
Of
Refpiration
219
Organs.
221
Mechaniim
of refpira¬
tion in
®an.
P H Y S I
excluded from air. We have feen a chameleon that
'lived, and was vigorous, for 22 months, without any
food, and which might have continued to live much
longer, but for an unfortunate bruife by a fall.
Other phenomena equally demonftrate the importance
of air to the living body. The frog leaps away wanting
its heart; it furvives the lofs of the greateft part of its
fpinal marrow 5 without its head, it lives for fome
days, and its heart continues to circulate its blood. Bo-
relli found, that eels and ferpents, though their bodies
be opened, and the whole of their bowels be taken out,
are able to move for a day after, and yet, in all thefe
animals, the life is obferved to be fuddenly extinguilhed
when the all-vivifying air is excluded. Even the fmall-
eft infedd has died, and the plant loft its vegetative
power, when retained for any conftderable time in a
vacuum. Fishes themfelves, when placed under an ex¬
hausted receiver, have ftarted anxioufly to the furface
•f the water in queft of frefh air ; and finding none,
have funk to the bottom and expired in convulfions.
It will prefently appear that this neceflity of air to life
is general in all the claffes of organized beings (k).
The organs of refpiration belonging to the human fy-
ftem, viz. the larynx, windpipe, lungs, diaphragm, ribs,
and numerous mufcles, have been fufficiently defcribed
in various parts of the article Anatomy ; and fome
account of thefe organs in the inferior animals has been
given in the fecond part of that article, N° 155, 156,
206, 208, 271 — 274, and in the articles Cetology,
Eepetology, and Ichthyology. For a more com¬
plete account of the refpiratory organs in the inferior
animals, the reader is referred to Cuvier’s Lepons d'Ana-
tomie Comparer, Le^.J xxvi. et xxvii. and to Blumen-
bach’s Comparative Anatomy, chap. xiv. and xv.
In examining the funftion of refpiration in warm¬
blooded animals, two circumftances are principally to
be confidered 5 the mechanifm of refpiration, or the me¬
chanical means by which the organs are enabled to re¬
ceive and expel the air, and the effefts produced by re¬
fpiration on the circulating fluids, and on the fyftem at
large. Our principal object in this article is briefly to
explain the mechanifm of refpiration •, to notice the ef-
fedts produced on the air by the refpiration of difterent
animals, with the eflfefts produced on them, and the re¬
lations that take place between refpiration and the pre¬
ceding functions of fenfation, motion, digeftion, and
circulation.
In order to make an infpiration, the intercoftal muf¬
cles, and the mufcular fibres of the diaphragm, are
thrown into contraftion, while at the fame time the ab¬
dominal mufcles, and the mufcular fibres of the wind¬
pipe, are relaxed. By thefe means the diaphragm being
drawn towards the facrum, and rendered lefs convex
towards the cheft, and the ribs being drawn upwards
(or forwards in quadrupeds), the cavity of the cheft is
enlarged, and the air remaining in the lungs being ra-
O L O G Y. Chap. VIII.
refied, the external air rufties in through the windpipe Of
by its own gravity, and diftends the lungs. In making ^efy*rat‘oni'
what is called a very deep infpiration, other mufcles
that are connedled with the atlantal ribs, viz. thofe
called fcalem, trape'zn, cervica/es defcendentes, ferrati
fuperiores, and peiftoral mufcles, a (lift to elevate the
ribs more than in an ordinary infpiration. By the ac¬
tion of the intercoftal mufcles the ribs are drawn atlan-
tad (upwards in man, and forwards in quadrupeds), be-
caufe the moft atlantal rib on each fide of the thorax is
fixed, and therefore all the other ribs are drawa towards
it 3 and they are alfo drawn peripherad (outwards), be-
caufe their greater curvature is in the direftion of the
facrum, and becaufe they turn on their vertebral extre¬
mities as on a fulcrum.
In order to make an expiration, the abdominal muf¬
cles, and the mufcular fibres of the windpipe, are con¬
tracted, while the intercoftal mufcles, and the mufcular
fibres of the diaphragm are at the fame time relaxed.
By thefe means, aided by the elafticity of the cartilages
of the ribs, and perhaps of the mediaftinum, the ribs are
drawn facrad (towards the facrum), while the dia¬
phragm, partly by its own mufcular aftion, and partly
in confequence of the preffure of the bowels, is rendered
convex towards the cheft. Thus, this cavity is confi-
derably diminifhed, the lungs are comprefied, and part
of the air is expelled through the windpipe. In making
a ftrong expiration, little more is neceflary than a more
po-werful contraftion of the abdominal mufcles. 222
The mechanifm of refpiration in mammalia is fo fi-in other
milar to that of man, that we need notenter into it 3 animals,
that of cetacea has been fufficiently explained under Ce¬
tology, N° 146—151 3 that of birds may be gather¬
ed from what has been faid on their ftnnfture, in the
comparative part of Anatomy, N° 271, and in Orni¬
thology, N° 37 3 that of reptiles has been fully ex¬
plained under Erpetology, page 3113 and that of
fifties under Ichthyology, page 73. The mechanifm
of this fun&ion in the claifes of animals below thefe is
fo fimple, that a confideration of it is unneceflary. In
infefts the air enters the numerous ramifications of the
tracheae; is carried by them into every part of the bo¬
dy, and is then returned by the fame paflages. In fome
of the mollufca, refpiration proceeds in a fimilar man¬
ner, by the ramifications of the pulmonary veffels that
enter by the neck 3 but in moft of thefe, and in all the
loweft tribes, fuch as worms and zoophytes, refpiration
feems to be carried on entirely by the pores of the
Ikin. # 223
Many attempts have been made to afcertain the quan- Quantity of
tity of air received and emitted in a fingle infpiration or air received
expiration. See Chemistry, N° 2535. This point
is not yet fully afcertained, but we may probably efti- '
mate the quantity expelled by each ordinary exfpiration
at one-feventh part of the whole contents of the lungs,
and that of the moft violent expiration at about four-
fevenths
(k) It was long ago obferved by Pliny, that if the bodies of infe£is are befmeared with oil, they foon perifli:
« oleo illito in feci a omnia exanimantur.'n The fame obfervation was afterwards made by Ray, who explained it by
Ihowing that in this way the pores through which the animals breathe are flopped. Mayow alfo found, that if the
®il be applied only to fome of thefe pores, the neighbouring parts become paralytic, while the reft of the body con-
iinued found. See Ray’s Wifdom of God, and Mayow’s Trad a tits.
%
Chap.
* Bojlcck
tn Jicfpi-
ration,
P- 35-
224
xn a au
*ute.
vnr. PHY
Of fevenths of that quantity *, or that the medium quantity
HeTpiration. 0f a|r confumed during a common infpiration or expira¬
tion is about 40 cubic inches *.
Another circumftance refpecting the mechanifm of
refpiration merits notice, viz. the ordinary number of
refpirations made in a minute by a healthy perfon. This
varies confiderably in different iubjedls, being in gene-
Jiumber of ra^ greateft in children, and leal! in old perfons. Dr
refpirations Hales eftimated the number of 20 in a minute j the
- m‘- fubjedt of Dr Menzies’ experiments refpired only 14
times in the fame period, while Mr Davy reckons his
refpirations at between 26 and 27 5 the fubjeft of the
experiments made by Meffrs Allen and Pepys, breathed
about 19 times in a minute, and with this Dr Thorn-
fon’s experience agrees. The average of all thefe is
about 20, which we may probably confider as a tolera¬
bly juft eflimate. Much, however, will depend on the
circumflances in which the perfon is placed j on his
habits of activity or indolence, of temperance or in-
temperance ; on the Hate of the atmofphere, &c.
Expetimen- The chemical changes produced on the air by the
tal writers refpiration of animals have been defcribed, fo far as
on refpira- lhey
were then known, under Chemistry, N° 2536.
Since that article was written, however, feveral valu¬
able obfervations have been pubHfhed, and the moft im¬
portant of thefe mull be here noticed ; but as we can¬
not, in this place, give any thing more than a fummary
fketch of thefe obfervalions, we thall here enumerate
the principal works that have appeared on this experi¬
mental part of our fubjeft. The chemical phyfiologifts
who have been moff confpicuous in thefe refearches are,
Mayow (in his TraBatus cle Refpiratione, or the AnaLj-
Jis of his works by Beddoes) ; Prieftley (Experiments
and Obfervations on Air); Lavoifier (Traite Elemen-
taire de Chitnie, Phyjical and Chemical EJfays, and a
work, on Atmofpheric Air) ; Goodwyn (On the Connec¬
tion of Life with Refpiration ) ; Coleman (On Safpend-
cd Refpiration ) ; Menzies (On Refpiration) ; Spallanza¬
ni (Memoires fur la Refpiration, tranflated into French
by Senebier, and lince into Englifh, and fapports de
I'Air avec les Etres O’-ganifes, &c. alfo collefted by Se¬
nebier) 5 Davy (Refearches Plu/ofophical and Chemical,
into the Nature of Nitrous Oxide; Ellis (Inquiry into
the EffeBs produced on Atmofpheric Air by Refpiration),
and Allen and Pepys (Philofophical TranfaBions, 1808,
Part II. or Phil. Mag. vol. xxxii.^). Moll of the fadls
obferved by thefe experimentalills, except thofe of the
three laft mentioned, have been collefled by Dr Bo¬
llock, in his EJfay on Refpiration, by Dr Thomfon in
his Syflem of Chemiftry, vol. v. third edition, and by
a,(5 Mr Johnfon in his Animal Chemiftry, vol. iii.
Afcertained The following changes produced on air that has been
changes on refpired by warm-blooded animals, feem to have been
refpired a:r. £uqy afGerta]n6£} . v;z> I# That the refpired air general¬
ly fuffers a fenlible diminution of bulk ; 2. That it lofes
a part of its oxygenous portion •, 3. That it acquires an
additional quantity of carbonic acid gas 5 4. That it is
charged with watery vapour. We fhall refume thefe
fuels, and confider the additional information which has
been acquired refpecling them fince the publication of
our article Chemistry.
1. Atmofpheric air generally fuffers, by the refpiration
of warm-blooded animals, a fenfible diminution in its
bulk.—The refults of the experiments made by different
cheiniils ©n the diminilhed volume of refpired air, are
HYSIOLOGY.
Its volume
fenfibly di-
rainiflied.
499
exceedingly various. Mr Davy makes the diminution Of
amount to one-eighteenth f of the whole air infpired j Refp|rabot/.
Lavoilier and Goodwyn eftimate it at no more than v
one-fixtieth and Dr Bollock fo low as one-eightieth jj, ^eJectrrh~
while Crawford and fome later experimentalills could '
perceive no diminution. Dr Thomfon Hates the re- on Refpi-
fults of his experiments upon this fubjefl to be, that in ratim,
fome cafes he could perceive no diminution at all, while
in others it wras perceptible. It was greatelt when the' ’ P'
animal was taken out repeatedly during the experiment,
or when he employed air purer than that of the atmo¬
fphere. He is difpofed to confider. the diminution as
accidental, and as owing to fome abforption of air, al¬
together independent of refpiration, and exceedingly
various in different circumllances $. In the Syftem of
ments of Meffieurs Allen and Pepys, the general wc-Chem.thuA
raee of the deficiency in the tola! amount of common ' ^11'vo*‘ v*
air infpired, appeared to be very fmall, amounting to1’ 7
about fix parts in 1000, and they are inclined to attri- ^
it, in a great meafure to the difficulty of exhaull-
the lungs fo completely after an experiment as be- vol. xxxii.
bute
ing the
fore it 228
2. Atmofpheric air, by the refpiration of warm-blooded Hart of its
animals, lofes a part of its oxygen.—From a ccmparifon °*ysen ab-
of the experiments of Mr Davy, with thofe made by^ia<^ct*'
Lavoifier jull before his death, Dr Thomfon eltimates
the quantity of oxygen confumed in a minute, by refpi¬
ration, at 31.6 cubic inches, making in 24 hours
4 ^04 cubic inches; and he concludes that in a day a
man confumes rather more than 25 cubic feet of oxy- f Svftem of
gen, and that he renders unfit in the fame time, {oxChemiJlry,
fupporting combuftion and refpiration, no lefs than 125 vo*- v‘
cubic feet of air -f. P"
3. Atmofpheric air acquires, by refpiration, an addi- Carboffic
ttonal quantity of carbonic acid gas.—The opinion ofacidgasac-
Dr Menzies, that the bulk of carbonic acid gas pro-8u‘red.
duced by refpiration, is precifely equal to that of the
oxygen loll, appears now to be fully confirmed. In Mr
Davy’s experiments they correfponded very nearly ^
and in thofe of Mr Dalton and Dr Thomfon, they cor-^’ * ’
refponded exactly. The latter chemill found, on the
whole, that the bulk of oxygen which difappeared was
fomewhat greater than that of the carbonic acid gene¬
rated •, but the difference varied confiderably, and kept
pace with the diminution of the bulk of air refpired.
Hence he confiders it as owing to the abltradlion of
part of the air by fome other way than refpiration, and
allowing for this abftraction, he has no doubt that the
bulk of the carbonic acid formed is precifely equal to
that of the oxygen that has difappeared. He is difpof¬
ed to confider the abfolute quantity of carbonic acid ge¬
nerated in 24 hours, as fomething lefs than 40,000 cu¬
bic inches on an average ||. The following refults ofU S)flern
the experiments made by Meffieurs Allen and Pepys, as ckem.
thefe were made on a large fcale, may be confidered as
quite fatisfaftory on this head. 1. It appears that the
quantity of carbonic acid gas emitted is exadlly equal,
bulk for bulk, to the oxygen confumed. 2. Atmo¬
fpheric air once entering the lungs, returns charged
with from 8 to 8.5 per cent, carbonic acid gas, and
when the contadls are repeated almoft as frequently as
poffible, only 10 per cent, is emitted. When the in-
Ipirations and expirations are more rapid than ufual, a
larger quantity of carbonic acid is emitted in a given
time *, but the proportion is nearly the fame, or about
3 R 2 eight
voi- v.
P- 737*
* Phil. ■
JWag.
Tel. xxxii.
p. 265.
*3°
Watery va¬
pour ac¬
quired.
500 • ^
. . eight per cent. The proportions of carbonic acid gas,
Relpirat;on.ja £nq. ancj |a^. port:Qns 0f a iufp
iration, differ
as widely as from 3.5 to 9.5 per cent. 3. it appears
that a middle-fized man, aged about 38 years, and
whofe pulfe is 70 on an average, gives off 302 cubic
inches of carbonic acid gas from his lungs in 11 mi¬
nutes } and fuppofing the production uniform for 24
hours, the total quantity in that period would be 39534
cubic inches, (agreeing almoji ex a cl I 1/ with Dr Thom-
fori's ejlimate') weighing 18,683 grains, the carbone in
which is 5363 grains, or rather more than n ounces
troy ; the oxygen confumed in the fame time will be
equal in volume to the carbonic acid gas 5 but it is evi¬
dent, that the quantity of carbonic acid gas emitted in
a given time, muff depend very much upon the circum-
ffances under which refpiration is performed j and here
it may be proper to notice, that all thefe experiments
were made between breakfaft and dinner. 4. A larger
proportion of carbonic acid gas is formed by the hu¬
man fubjeef, from oxygen than from atmofpheric
air *.
4. Atmofpheric air returns from the lungs charged
zvith aqueous vapour.—Of this circumitance there is no
doubt, but the quantity of water contained in the expired
air, and the fources from which it is derived, are ftill in
difpute. Dr Thomfon effimates the former at about 19
ounces per day; but he does not lay much ftrefs on the
refults of his own experiments, as they wrere not futE-
c.'ently varied to give a fair average. As to the fources
of this watery vapour, it has been generally fuppofed,
that the water is formed in the lungs by a combination
of part of the oxygen confumed with hydrogen evolved
from the venous blood. This, however, is mere hypo-
theEs. It has not been proved that hydrogen *is evolved
from the blood ; and as the quantity of oxygen con¬
fumed appears to be taken up in forming the carbonic
acid gas that is expired, there is none left to form wa-
. ter. No hydrogen, or any other gas, except carbonic
acid and azotic gas, appear to be evolved during the
procefs of refpiration f.
There is another change fuppofed by mod: chemical
phyliologifts, to be produced on the air by refpiration,
namely the lofs of part of its azote ; but this is Hill dif-
puted. Dr Bollock concludes it to be probable, that
a fmall portion of azote is loll, which he ellimates on
an average at of the air refpired, making in 24
I Eq/ajs on hours, about 4.5 ounces, or four cubic feet Mr
Refpira- Davy found the confumption of azote to amount to
\0^efearch ab°ut one feventh of that of oxygen || ; and feme late
es, p. 433. experiments of Dr Henderfon afford a fimilar refult,
§ Nicholf. though in thefe the proportion is rather lefs §. Dr
Jourfvo. Thomfon alfo found a lofs of azote, but it was extreme¬
ly inconllant, fometimes being fcarcely perceptible, at
others conliderable. It kept pace with the diminution
of the bulk of the air refpired, and with the difference
between the bulk of the oxygen confumed, and the car¬
bonic acid formed. He conceives that a portion of the
air refpired difappears without undergoing any change,
and that this portion occafions the diminution of the
azote, ahd the difference between the bulk of the car¬
bonic acid formed, and that of the oxygen confumed.
He thinks it conceivable, that the difappearing of fuch
a portion may be confined to the unnatural circumllan-
ces occafioned by the experiment; that the difficulty of
throwing out the air from the lungs in thefe circumllan-
PHYSIOLOGY. Chap. VIII.
ces, may be fuch as to induce abforbents to a61, and Of
f Phil.
££ag. xxxii.
p. 269,
231
Is azote
loft?
vo!. viii.
* 44
remove a portion which in the ordinary Hate of the R^fyuation.
lungs would have been thrown out by expiration \
Experiments on the changes produced on atmofphe- chim.'
ric air and oxygenous gas, by the relpiration of the in vol. v.
ferior animals, have been made chiefly by Vauquelin,P-7J8<
Spallanzani, and Mr Davy, and 1’ome of them have been rl f2
repeated and varied by Mr D. Ellis. From all thefe
experiments we find, that, by the refpiration of ampin- the refpira-
bia, of filhes, of infebls, of mollulca, and of worms, thet on?t tiie
air in which they have been confined liiffers changesn'ferlor am“
analogous to thole produced in it by the refpiration of'™1115'
the warm-blooded animals ; that the oxygenous part is
diminiffied, and that this diminution is moll complete
when infects and worms have been confined in it; that
carbonic acid gas is in all cales produced, but that the
quantity produced varies in different animals, that filhes
live for the ihortelt time, and amphibia and worms for
the longelt, when confined in a certain quantity.
From the latell experiments made by Spallanzani,
on the effects both of living and dead animals, on at-
mofpheric air, as collected by Senebier, that experimen-
talill has drawn the following conclufions. 1. In begin¬
ning with worms, and riling up to man, there is no ipe-
cies of animal which does not deltroy the oxygen of the
atmofphere after death, and deltroy it entirely if it be
kept incloled in it, provided the quantity be not too
great in proportion to the fize of the animal; becaufe a
confiderable time is required when the volume of air
is large, and a lefs time when the quantity is fmail.
2. This deftruttion of oxygen by dead animals, is un¬
der fimilar circumltances flower than that effected by
living animals, if we regard merely the effects produced
by the cutaneous organ, independent of the action of
the lungs.
3. He thought he had legitimately proved, that the
deltruftion of oxygen by the cutaneous organ, is not
occafioned by the combination of this gas with the car-
bone of the animal; but that it is a true abforption of
that element, by the body of the animal deprived of
life. It does not give out carbone, but carbonic acid,
as he believed he had proved by unanfwerable experi¬
ments.
4. The abforption of oxygen by animals cut into fmall
pieces, is greater than that occafioned by animals entire
in fimilar circumltances.
5. A cold blooded animal of the fame bulk, and in
the fame circumltances as a warm-blooded animal, ab-
forbs more oxygen than the latter after death.
6. The Ikin is not the only part of an animal which
abforbs oxygen ; all the parts, folid, fluid, and foft, not f Edin.
excepting the drielt horny parts, as the nails of qxia.-Med. Jour.
drupeds, the bill and feet of birds, produce the fame ef-vo1-v-
feft f. P- I05-
It has long been known that plants would not vege- Effedls^of
tate, if excluded from atmofpheric air. Papin confined vegetation
an entire plant in the exhaulted receiver of an air-pump, on the air.
and it foon perilhed ; but on keeping a fimilar plant in
this vacuum, with only its leaves expofed to the air, it
continued to live for a long time J. When the leaves j Darrwin->s
of a plant are llript off, or blighted by infects; when Phytologia,
they have the upper furface fmeared with oil, with var-P- 51-
nifti, or laid upon water the plant dies in a few days. § FMis's
Hence it is evident that the leaves of a plant are necef- Inquiry,
fary organs, and that there is produced on the air inP, 2S*
which
Chap. VIII.
P H Y S I
Of
Kefpiratior
* Ellis's
Inquiry,
P- 39-'
etfeq. ■
234
ElFeias ©f
refpiiatioxi
©n the ani¬
mal fjfteoi.
235
Changes on
the bleed.
236
Increafe of
tempera¬
ture.
237
Theory of
refpirhtion.
238
Theory of
Allen and
Bollock.
which the plant vegetates, feme change effential to the
■healthy action of the plant. What this change is, has
not been fully afcertaxned. It is the general opinion,
that the leaves abforb a portion of the atmofphere, and
give out certain gafeous produ&s •, and it is generally
believed, that molt plants have the property of giving
out oxygenous gas during their expofure to the light,
and azotic gas or feme other irrefpirable air in the
dark. That oxygenous gas is necelfary to vegetation,
is fully proved ; and it feems certain, efpecially from the
expe riments of Mr Ellis, chat under the ordinary cir-
eumiiances, carbonic acid gas is generated during their
vegetation *. Mr Ellis, who is not fatisfied with the
accuracy of the experiments of Scheele and Prieltley,
feems to doubt whether plants at any time give out oxy¬
genous gas 5 and thinks that the principal ufe of oxygen
to them, is to combine with the fuperfluous carbone
produced by vegetation, and thus form the carbonic acid
evolved.
Having confidered the effe&s produced on the air by
the refpiration of animals, and the vegetation of plants,
wre muff now notice the effects produced by the exercife
of the fame fundfion on the animal body, as the compa-
rifon of thefe effefts with the changes produced on the air
itfelf, affords us the only clue to a rational theory of re¬
fpiration.
We have already ftated (CHEMISTRY 2540), that
during refpiration, the blood changes from the dark co¬
lour which it has in the veins, to the bright fcarlet of
arterial blood. It has been found, that a clot of venous
blood, when out of the body, affumes the bright tinge,
when expofed to the adfion of oxygenous gas ; and that
venous blood confined within a bladder, undergoes a fi-
milar change, when the bladder is immerfed in oxygenous
gas. It has been alfo found, that when arterial blood
out of the body is expofed to the affion of irrefpirable
gafes, it lofes its bright colour, and affumes the purple
hue of venous blood.
It is fully afeertained, that the heat of the body is
chiefly kept up by refpiration, See Chemistry, N°
2545-
Let us now confider the moil probable theories of re¬
fpiration, chiefly as they are applicable to the human
fyflem. Without flaying to notice the older hypothefes
that have been advanced to explain this fundfion, we
fhall only ftate the prefent moft received dodtrine, and
mention the objedtions that have been lately made to it.
This dodfrine is ffated in the following manner by Dr
Bollock, one of its moft ffrenuous defenders. “ The
blood arifes at the right fide of the heart, in a venalized
ftate, loaded with a quantity of the oxyde of carbone ; as it
paffes through the pulmonary veffels, it becomes fubjedted
to the action of the air contained in the bronchial cells ;
a portion of the oxygen is removed from the air, part of
which, forming an intimate union with the oxyde of car¬
bone, is expelled in the form of carbonic acid gas, while
the remainder is diffolved in the blood.” It is here
neceffary to remark, that it is not oxygenous gas, but
oxygen, which is fuppofed to be mixed wdth the blood.
The caloric thus fet at liberty is employed, part of it in
maintaining the temperature of the lungs, which would
otherwife be cooled by the admifiion of the external air ;
part of it in carrying off the aqueous vapour, and another
portion in converting the carbonic acid into carbonic
acid gas j but the greateft part of it is united, in the
O L O G Y. 501
form of fpecific heat, to the arterial blood, which-, by Of
becoming arterialized, has its capacity for heat-increai- R' fpnv.tiop.
ed. The arterial blood is poured into the left cavity of “ v
the heart, and propelled through the arteries into the
extreme parts of the body. The oxygen which was dif¬
folved in the whole mafs of blood, during the circula¬
tion, gradually unites itfelf more intimately to a portion
of the carbone in itj which it converts into the oxide of
carbone, and thus the blood acquires the venous ftate.
By this change, its capacity for caloric is diminithed j
the fpecific heat which it obtained in the lungs, is given
out in the capillary veffels, to keep up the temperature
of the body, and the blood returns to the right fide of
the heart completely venalized. This hypolhefis is near¬
ly fimiiar to the one which was propofed by M. M. La
Grange and Haffenfratz it received fome modifications
from Mr Allen of Edinburgh, and was delivered by him
nearly in the form which I have ftated above, in his ad¬
mirable courfe of phyfiological ledtures. It was, I be¬
lieve, firft publiihed in my Effay on Refpiration * Edin.
This doctrine, if fufficiently eftablifhed, would explain Med. Jour-
the manner in which the blood becomes arterialized in
the courfe of the circulation. It would alfo (hew how,iJ’ 1
under particular circumftances, the arterial blood may
be venalized without leaving the arteries, and the venous
blood arterialized without leaving the veins. It accounts
for the gradual evolution of caloric in the capillary vef¬
fels, during the courfe of the circulation, by the union
which takes place between the oxygen and the carbone j
whereas in the other hypothefis, (fee N° 241.5) this union
is entirely completed in the lungs. It would allow a
confiderable time in which this union might be accom-
plilhed, and would likevvife fuppofe the conftituent parts
to remain in perfeft contadl for an indefinite period.
This hypothefis would alfo explain how the oxygen is
difpofed of, which is fuppofed not to be concerned in the
formation of carbonic acid, and would likewife poffefs
the advantage of fuppofing the exiftence of a furplus
quantity of oxygen, which being carried along the cir¬
culation, might be expended in a variety of ufeful pur-
pofes in the different parts of the animal economy. It
would (hew how the fupply of matter which is poured
into the blood by the abforbents, is gradually incorporat¬
ed with the mafs } and after the reparation of that por¬
tion, which is neceffary for repairing the wafte of the
different organs, the remainder is united to oxygen, and
keeps up the temperature of the body ; and, having af¬
terwards no farther ufeful purpofe to ferve, it is difehar- ,
ged by the lungs f. .
Several objeftions, however, may be made to this Objections
theory. It is not proved that there is in natural refpi¬
ration any abforption of oxygen by the blood ; for though
much of the oxygenous portion of the atmofphere is loft,
the quantity of carbonic acid generated is fufficient to
account for it. Mr Ellis has lately made very ftrong
objections to this fuppofed abforption of oxygen, drawn
chiefly from the anatomical ftructure of the blood vef¬
fels, and of the bronchial cells. He contends that the
coats of the former, and the membranes bounding the
latter, can fcarcely admit the paffage of air through
them, much lefs that of the folid bafis of oxygenous gas,
which bafis Dr Boftock fuppofes to be the principle ab-
forbed. It is ftill more improbable, according to Mr Ellis,
that two folid bafes, namely thofe of oxygenous gas, and
of oxide of carbone, ftiould be at the fame time palling ■
through
■ | Enis's
Inquiry,
p. ir7.—
IZ3.
240
anfwered.
502 P H Y S I
Of through thefe refifting membranes} a fuppofition that is
Refpiration. neceflTary in the hypothecs juft ftated. Again, fuppofing
that this abforption of oxygen ftiould take place, from
the affinity of the blood for this principle, it is not eafy
to conceive why this affinity ihould fo foon ceafe, and
why the blood ffiould again part with the oxygen, to the
bafe of carbonic oxide Thefe objections are certain¬
ly very forcible j let us fee how they have been anfwer¬
ed.
Dr Boftock, in an ingenious reply to Mr Ellis’s ob¬
jections, in invalidation ot the firft objection, quotes the
well-known experiment of Dr Prieftley, mentioned in
N° 235. that venous blood becomes changed when ex-
pofed to oxygenous gas, even though a bladder be in-
terpofed between them j and in controverting of the reft,
he feems chiefly to rely on the fuppofition that a greater
quantity of oxygen is confumed than is taken up in the
formation of the carbonic acid. He alfo does not confi-
der it as necejffary to fuppofe that either the oxygenous
gas, or the oxygen itfelf, ftiould enter the blood-veffsls,
and ffiould afterwards be expelled from them j but on¬
ly that a part of the oxygen fliould be attracied by the
blood, and after entering into a variety of new combina¬
tions, ffiould be difeharged as a conftiluent of fome of
thefe new compounds. Without inquiring in what way
the aCtion between the blood and oxygen takes place •,
whether it be in confequence of the mechanical itruCiure
of the membranes, which permits the oxygen to pafs
through their pores, or whether it be owing to the affinity
of the blood for oxygen, which c^ufes it as it were to be¬
come faturated with this fubftance before it tranfrnits it $
it appears to him fufficient to ftate, that oxygen and
Med. Jour, blood can ad on each other, through a membrane which
is very much thicker, and pfobably much denfer, than
that which feparates the blood in the lungs from the air
in the bronchial cells *.
From a confideration of the principal experiments on
refpiration that have been made by the ableft chemical
phyfiologifts, and a comparifon of thefe with what he has
himfelf made, Mr Ellis contends that no part of the air
enters into the blood, but all the oxygen which difappears
is to be found in the carbonic acid produced ; and that
this carbonic acid is formed by the union of carbone
emitted by the exhalant vefi'els of the lungs, uniting with
part of the oxygenous portion of the infpired air f.
To this opinion Dr Boftock, in the paper already re¬
ferred to, makes the following objections; that this opi¬
nion does not explain how the regular fupply of carbone
is, at each fucceffive circulation, brought to the lungs in
a ftate proper to be difeharged j and that it does not ex¬
plain in what way the oxygen is employed, which is con-
fumed in refpiration f.
To the firft of thefe objections (which, if it be prov¬
ed that the whole of the oxygen is taken up in forming
carbonic acid, is the only objection that can properly lie
againft his opinion), Mr Ellis replies, that the fupply of
carbone is derived from the digeftive organs *, but he
does not conceive, as Dr Boftock feems to imagine, that
this is no fooner received into the blood than excreted,
or that the firft operation which takes place in the fan-
guiferous fyftem after it has received the fubftanoe which
is to afford nutriment to the body, is to difeharge the
greateft part of it. He regards carbone as a conftituent
part of the animal fluids, and he has endeavoured to
jhew, that it is emitted by the exhalants of the ikln and
3
* Ed in.
vol. iv.
p. 161.
etfeq.
241
Mr Ellis’s
opinion.
f Edbu
P- 327-
242
Objections
f Edin.
Jour.
r«l. iv.
p. 163.
243
anfwered.
O L O G Y. Chap. VIII.
inteftines, as wTell as by thofe ©f the lungs, producing in Of
all cafes fimilar changes on the air. Digeftion he holds Refpiratiorf,
to be in no other -way the fource of the carbone in thefe
fluids, than as it is the fource of all the other principles
which they contain. We know that all the phenomena
of refpiration are often exhibited for long periods where
no digeftive procefs is carried on ; but the functions of
life muft fooner or later come to an end, if the various
means of exhauftion be not recruited by fupplies through
the digeftive organs. It is only in this diftant view that
he confiders digellion as the fource of carbone ; its im¬
mediate fources are the exhalant functions of the body,
which will afford carbone as long as they are fupported
by the motion of the blood, and will no longer yield it
when the motion of the blood has ceafed. But whether * Edin.
the exhalant functions continue or ceafe, he confiders y°ur/
that carbone exifts abundantly, if not equally, in the fe- vol‘l^’
rum and craffamentum, in arterial and venal blood *.
On the whole, though the final caufes of refpiration, Theory of
or the ufes to which it is fubfervient in the animal eco- refpiration
nomy, are now pretty well underftood, we muft acknow-iDcona"
ledge that the mode in which thefe beneficial effeCts are P '~e'
produced, has not yet been fatisfaCtorily explained. 24;
The principal ufes of refpiration appear to be, 1. To Ufes or re¬
bring about fome beneficial change in the fluids of the (Pirati0R-
body, and through them on the folids; 2. To preferve
the equable temperature of the body ; and 3. In all thofe
animals that breathe by lungs to produce thofe founds
which arife from what we call voice.
That animal heat is kept up chiefly by refpiration, Animal
requires we think, no particular proof. It is well known, heat,
that thofe animals which confume moft air during refpi¬
ration, have the higheft temperature. Birds in particu¬
lar have the moft extenfive breathing organs, and the
temperature of thefe animals is higher than that of any
other clafs. The refpiration of reptiles, fifties, and moft
of the lower claffes, is flow and languid, and the tempe¬
rature of thefe animals is proportionally low. The heat
of each fpecies is, however, pretty uniform under ordi¬
nary circumftances. That of the human body is gene¬
rally about 98° of Fahrenheit. This however depends
on the circumftances in which it is placed. When much
chilled by the adftion of cold, the temperature of the hu
man body falls a degree or two below the ordinary
height; and under the influence of violent fever, it rifes
feveral degrees above it. The temperature is generally
higheft in children •, and inftances are recorded of thefe
having furvived, while their mothers, to whofe breafts
they clung, have periffied from the feverity of cold.
One of the moft interefting fadfts relating to the fob- Preferva-
je<ft of animal heat, is the capacity of preferving the tion of
equable temperature of their bodies, poffeffed by moft ani- equatfle
mals. Man himfelf can live with little inconveniencetempera’
in the frozen regions of Spitzbergen, and under the equa¬
torial heats of Africa. He can even fupport a greater
degree of heat than is perhaps ever known to take place
from the rays of the fun, as is proved by the experiment
of Drs Blagden and Fordyce in heated rooms ; thefe
gentlemen having remained for 15 minutes together in
a heat exceeding 130°. The heat fupported by fome of
the inferior animals is ftill more extraordinary. A dog
has been known to live for a confiderable time in air
heated to 260°, and ftill the heat of his body was not
raifed more than 2° above its natural ftandard. A frog
has lived for more than 25 minutes when laid on flan¬
nel,
Chap. VIII.
PHYSIOLOGY.
503
Of nel, heated from 950 to 10C0. Fiihes live very well at
Reflation. y2o . anci Lucas, in his hiftory of mineral waters, fpeaks
v' 1 of carp that were living in a hot bath, whofe tempera¬
ture was at leaf! equal to that of the human body.
How this equable temperature is preferved, cannot be
completely explained. We know that the heat of the hu¬
man body is commonly moderated by perfpiration j but
in fome cafes, as in that of Dr Fordyce alluded to above,
where the heated atmofphere was filled with watery va¬
pour, this could have little efFeft. We can afcribe it on-
!.(S ly to the aftion of the living principle.
V*ice. It was long ago obferved by Ariilotle, that thofe ani¬
mals only who poffefs lungs, have a true voice, and this
opinion is confirmed by the experience of modern na-
turalifts. We find, that only mammalia, cetacea, birds,
reptiles and ferpents, can utter vocal founds. Several
tribes below thefe do indeed emit certain founds, efpe-
cially infedls; but thefe are owing to vibrations of the
air in confequence of the agitation of their external or¬
gans. It is only in mammalia and birds that the voice
becomes an interefting objedf of enquiry ; for that of the
cetacea is little more than blowing and grunting, and
that of the other two claffes is either hi fling or croak-
249 ing- . . . .
Amazing Nothing can exceed, in variety and execution, the hu-
vanety of voice } as will readily be allowed, if we confider
the human ^ complicated ftrufture of the human vocal organs, and
VOiCC* A # o '
the almoft infinite variety of changes of which they are
fufceptible. Dr Barclay has calculated thefe with great
accuracy, proceeding on the principle, that where a num¬
ber of moveable parts conftitutes an organ deitined to
fome particular funftion, and where this funfh’on is va¬
ried and modified by every change in the relative fitua-
tion of the moveable parts, the number of changes pro-
duceable on the organ muft at leaf! equal the number of
mufcles employed, together with all the combinations
into which they can enter. Now, the mufcles proper to
the five cartilages of the larynx, are at leaf! feven pairs j
and fourteen mufcles that can aft feparately or in pairs,
in combination with the whole, or with any two or
more of the reft, are capable of producing 16,383 dif¬
ferent movements •, not reckoning as changes the vari¬
ous degi'ees of force and velocity, nor the infinitely va¬
ried order of fucceflion by which they may occafionally
be brought into aftion. The number appears almoft
incredible ; but to leffen the furprife, it muft be recol¬
lected that we fpeak not here of the powers poftefTed by
any individual, which will depend on habits and circum-
ftances, but of the powers of the vocal organs, confider-
ed in the abftraft, free from all the influence of cuftom,
equally indifferent, and equally difpofed to aft in any
order of fucceflion, in any combination, and with any
degree of force and velocity of which their original
powers were fufceptible.
If the powers we have mentioned appear aftonifhing,
and able to account for many thoufands of thefe varieties
obferved among the voices of the human fpecies, we have
further to add, that the mufcles alluded to are only the
proper mufcles of the larynx, or the mufcles reftrifted in
their attachments to its five cartilages. Thefe are but a
few of the mufcles of voice. In fpeaking we ufe a great
many more. Fifteen pairs of different mufcles, attached
to the cartilages, or os hyaides, and afting as agents, an-
tagonifts, or direftors, are conftantly employed in pre-
ierving the cartilages of the larynx fteady, in regulating
the place of their fituation, or moving them as occafion Of
requires, upwards and downwards, backwards and for- Respiration,
wards, and is every way, direftly and obliquely, accord- v
ing to the courfe of the mufcular fibres, or in the diag¬
onal between different forces. Thefe mufcles, independ¬
ent of the former, are fufceptible of 1,073,741,823 dif¬
ferent combinations 5 and co-operating with the feven
pairs of the larynx, of 17,592,186,044,415, exclulive of
the changes which muft arife from the different degrees
of force and velocity, and the infinitely varied order of
fucceflion in which they may be brought into aftion.
But thefe are not all that co-operate with the larynx,
either in forming or changing the voice } the diaphragm,
the abdominal mufcles, the intercoftals, and all that di¬
reftly or indireftly aft on the air, or on the parts to
which the chondral and hyoidal mufcles are attached,
contribute their {hare. The os hyoides could not be raif-
ed unlcfs the inferior jaw-bone were previoufly fixed by
the temporals, majfeters, and internal pterygoids ; and a
fimilar afliftance is likewife furnifhed by feveral other
auxiliary mufcles that fix the head.yPe/vmw, and fcapula ;
to thefe we muft add fome pairs belonging to the pharynx
and ijlbnus faucium, and fome alfo belonging to the
tongue, which, combining with others, give to that Or¬
gan an inconceivable variety of movement \ and fo quick¬
ly, that, in rapid utterance, they change its ftate 3000 f Barclays
times in a minute. Thus'Haller could articulate i^QO^’,at-
letters in a minute, which required 1500 centraftions,^™^-
and as many relaxations of the lingual mufcles f.
The principal organ of voice is the larynx, which isMechanifm
proved by the circumftance that, when this is injured,of voice
the voice is either loft, or rendered very indiftinft. In anc* fpeec^*
ordinary refpiration the chink of the glottis feems to be
in a relaxed ftate, and when this chink is contrafted,
voice is produced, and the found of the voice is more or
lefs Ihrill, according as the glottis is more or lefs con¬
trafted. By this contraftion of the glottis alone wre can
produce only inarticulate founds, varied indeed almoft
infinitely with refpeft to intenfity and tone, by the ac¬
tion of the mufcles. The produftion of fpeech requires
the aftion of the tongue, the lips, the palate, and the
teeth ; and the articulations are moft complete, when all
thefe parts are moft perfeft in their ftrufture, and in the
moft healthy condition. Tod great length or ftiortneis .
of the tongue, fwelling of this organ in confequence of
inflammation, &c. imperfeftion of the palate, lofs of
the teeth, fwelling of the lips, all ferve to render fpeech
imperfeft and inarticulate. The ftrength of the voice
depends on the quantity of sir expired, and on the con¬
traftion of the glottis j and, confequently thofe animals
who have the moft capacious and moft dilatable lungs,
together with an ample cartilaginous and elaftic larynx,
will, other things being equal, have the ftrongeft voice. 2 ^r
Among the various effefts of the human voice, there Vemrilo- -
is none more calculated to produce furprife in the hear-T1^1®*
ers, than that extraordinary talent which fome men pof¬
fefs of deceiving their hearers into a belief, that the
founds wflnch they utter do not proceed from the real
fpeaker, but from fituations at a diftance. This talent
has been termed ventriloquifm, from an idea that the
voice of the fpeaker proceeded not from the mouth, but
from the belly. The moft remarkable inftance of this
rare talent of which we have heard, is that of M. Fitz-
James, who was formerly at Paris, and exhibited in
London in the year 1803. Mr Nicholfon has given an
amufing
5C4
PHYSIOLOGY.
Chap. VIII.
Of amufing account of the performance of this ventriloquiif,
Refpiiation.anj we {hall prefent part of it to our readers.
v " After ibme remarks on the nature of ventriloquifin,
which we {hall notice prefently, and on the difficulty of
afcertaining the diredtion of the found, Mr Nicholfon
thus proceeds :—“ We lliould fcarcely be difpofed to a-
fcribe any definite direction to it} and confequently are
readily led to fuppofe it to come from the place bell
adapted to what was faid. So that when he wrent
to the door, and alked in French (in which the whole
performance was carried on), ‘ are you there ?’ to a per-
fom fuppofed to be in the paflfage, the anfwTer in the un-
ufual voice was immediately afcribed by the audience to
a perfon abfually in the paffage 5 and upon {hutting the
door and withdrawing from it, when he turned round,
direbting his voice to the door, and faid, ‘ flay there till
I call you,’ the anfwer which v’as lowrer, and well adapt¬
ed to the fuppofed diftance, and obftacle interpofed, ap¬
peared {till more flrikingly to be out of the room. He
then looked up to the cieling and called out in his own
voice, ‘ wffiat are you doing above ?’ ‘ do you intend to
come down ?’ to which an immediate anfwer was given,
which feemed to be in the room above, ‘ I am coming
down direbtly.’ The fame deception was prablifed on
the fuppofition of a perfon being under the floor, who
anfwered in the unufual, but a very different voice from
the other, that he was down in the cellar putting av/ay
fome wine. An excellent deception of the wTatchman
crying the hour in the ftreet, and approaching nearer the
houfe, till he came oppoflte the window, was prabtifed.
Our attention w-as direbted to the ftreet by the marked
attention which Fitz-James himfelf appeared to pay to
the found. He threw up the faffi and alked the hour,
wffiich wras immediately anfwered in the fame tone, but
clearer and louder •, but on his {hutting the window dowm
again, the watchman proceeded lefs audibly, and all at
once the voice became very faint, and Fitz-James in his
natural voice faid, ‘ he has turned the corner.’ In all
thefe inftances as w^ell as others w hich were exhibited to
the veiy great entertainment and furprife of the audience,
the acute obferver will perceive that the direblion of the
found was imaginary, and arofe entirely from the well-
ftudied and {kilful combinations of the performer. Other
feenes-which were to follow- required the imagination to
be too completely miiled to admit of the ablor being
feen. He wrent behind a folding fereen in one corner
of the room, when he counterfeited the knocking at a
door. One perfon called from within, and w-as anfwer¬
ed by a different perfon from without, who was admit¬
ted, and w-e found from the converfation of the parties,
that the latter w as in pain, and defirous of having a tooth
extrabled. The dialogue, and all the particulars of the
operation that followed, would require a long difeourfe
if I were to attempt to deferibe them to the reader. The
imitation of the natural and modulated voice of the ope¬
rator, encouraging, foothing, and talking with the pa¬
tient j the confufion, terror, and apprehenfion of the fuf-
ferer the inarti mlate noifes produced by the chairs and
apparatus, upon the whole, conftituted a mafs of found
which produced a ftrange but comic effebt. Some ob-
fetvers w-ould not have hefitated to affert, that they
heard more than one voice at a time; and though this
certainly could not be the cafe, and it did not appear
fo to jue, yet the tranfitions were fo inflantaneous, with¬
out the leaft paufe between them, that the notion might
very eafily be generated. The removal of the fereen Of
fatisfied the audience that one performer had effebled the Refpirations
wThole. y—w
“ His principal performance, however, conflfted in the
debates at the meeting of Nauterre, in which there were
twrenty different fpeakers, and certainly the number of
different voices was very great. Much entertainment
wTas afforded by the fubjebt, which was taken from the
late times of anarchy and convulfion in France ; when
the low-eft, the moft ignorant part of fociety, was called
upon to decide the fate of a whole people by the ener¬
gies of folly and brdte violence. The fame remark may
be applied to this debate, as to the other feene refpebting
tooth-drawing j namely, that the quick and fudden Iran-
fttions, and the great differences in the voices, gave the t Philof
audience various notions, as well with regard to the num-.70?y- 8vo’
ber of fpeakers, as to their pofitions and the direblion of !v‘
. n r P- 203.
their voices f^
Various explanations of this peculiar modification of How cx-
voice have been given. From the report of Fitz-James piahied,
himfelf, it appeared to Mr Nicholfon, that by long prac¬
tice he had acquired the faculty of fpeaking during the
infpiration of the breath, with nearly the fame articula¬
tion, though not fo loud, nor fo varioufly modulated, as
the ordinary voice, formed by expiration of the air. M.
Richerand, who heard Fitz-James at Paris, gives a dif¬
ferent account of the matter. He fays that every time
the ventriloquilt exerted this unufual peculiarity, he fuf-
fered diftention in the epigaftric region •, that lometimes
he perceived the wind rolling even lower, and that he
could not long continue the exertion without fatigue.
Richerand believes that the whole mechanifm of this art
confifts in a flow, gradual expiration, drawn in fuch a
w-ay, that the artift either makes ufe of the influence ex¬
erted by volition over the mufcles of the parietes of the
th®rax, or that he keeps the epiglottis down by the bafe
of the tongue, the apex of which is not carried beyond
the dental arches.
He always made a ftrong infpiration juft before this
long expiration, and thus conveyed into the lungs a
confiderable mafs of air, the exit of w-hich he afterwards
managed w-ith fuch addrefs. Therefore repletion of the
flomach greatly incommoded the talent of M. Fitz-
James, by preventing the diaphragm from defeending
fufficiently to admit of a dilatation of the thorax, in pro¬
portion to the quantity of air that the lungs ffiould re¬
ceive. By accelerating x>r retarding the exit of the air, he
can imitate different voices, and induce his auditors to a
belief, that the interlocutors of a dialogue kept up by
himfelf alone, are placed at different diftances J. 1 Riche-
Mr Gough in an ingenious paper, containing an in- P^”^
veftigation of the method whereby men judge, by the He'rrifont
ear, of the pofition of fonorous bodies, relative to their p. 370.
own perfons, explains the phenomena of ventriloquifm,
on the principles of reverberated found, and confiders it
as confifting in the talent of making the voice iffue on¬
ly from the mouth ; whereas he thinks that in ordinary
cafes the different vibrations which are excited by the
joint funbtions of the feveral vocal organs in ablion, pafs
along the bones and cartilages from the parts in motion,
to the external teguments of the head, face, neck, and
cheft, from which a fucceffion of fimilar vibrations is im¬
parted to the contiguous air, thereby converting the up¬
per half of the fpeaker’s body into an extenfive feat of
found. He thinks that the founds proceeding from the
' mouth
ter Me¬
moirs, vol
622.
.*53
Voice ol
brutes.
Chap. VIII. P H Y S I
mouth of a ventriloquift are uttered in fuch a direftion
Refpiration. that the h
earers may receive the imprelTion of fome
echo with much more force than they can receive the
♦ Manchef- original founds *. It may be doubted whether fuch
echoes can take place in an ordinary room filled with a
large ailembly ; and on the whole we are inclined to
■'confider this phenomenon as being effedted partly by the
gradual emilTion and a fkilful management of a large
quantity of air taken in by a full infpiration, and partly
by the influence which the performer is capable of ex¬
erting over the imagination of his hearers.
Several of the mammalia have a charafteriftic voice,
which is formed by particular organs. Thefe are in
fome animals tenfe membranes j in others peculiar cavi¬
ties opening into the larynx, and fometimes appearing
like continuations of the laryngeal ventricles. Thus
the neighing of the horfe is effefted by a delicate, and
nearly falciform, membrane, which is attached by its
middle to the thyroid cartilage, and has its extremities
running along the outer margins of the opening of the
glottis. The braying of the afs is produced by means
of a fimilar membrane, under which there is an excava¬
tion in the thyroid cartilage. In this animal there are
alfo two large membranous facs opening into the larynx.
The purring of the cat feems to be owing to two deli¬
cate membranes that lie below the ligaments of the
glottis. Some of the monkey tribe, eipecially the Ji-
tnia feniculus and beelzebul, have the middle and fore
part of the os hyoides formed into a fpherical bony cavi¬
ty, by which thefe animals are enabled to produce thofe
horrible and penetrating tones, which can be heard at
^at- chap. vaq. (finances, and have gained them the name of howl¬
ing apes f. See Mammalia, N° 33.
The fimplett vocal organ feems to be that of birds.
Thefe animals have, on the fides of the windpipe next
the lungs, and at the opening of the bronchiae, two
membranous folds which partly clofe the pulmonary
aperture of the windpipe, and the aperture next the
head is fufceptible of great contradfion and dilatation.
In thort, the vocal organ of birds may be confidered as
one of the moft perfect wind inilruments, very much
refembling, both in its ftru£lure and effeft, a clarinet or
hautboy, the opening next the lungs being fimilar to
the reed of thefe inftruments. For fome remarks on
the fong of birds, fee Ornithology, N° 42 ; and for
farther obfervations on the voice, fee Anatomy, Part I.
N° 122.
In tracing the relations of refpiration with the pre¬
ceding functions, we mull deviate a little from our ufual
order, and begin with thole between refpiration and
circulation, as it feems to be through the medium of the
circulating fyftem that refpiration principally a£ts on the
other funddions. The relations between refpiration and
With circa- circulatj°n are the moft immediate and the moft obvi-
latian. ous. When the breathing is moft free and rapid, the
circulation is moll vigorous and adtive *, while in labo¬
rious or interrupted refpiration, the a£lion of the heart
and arteries becomes flow, feeble, irregular; and where
the lungs are deprived of oxygenous gas, the arteries
gradually ceafe to pulfate, and foon after the motion of
the heart ceafes. If the ftimulus of oxygen be not too
long withheld, fo that the lungs can again be excited to
action, firlt the heart, and then the arteries, gradually
renew the exercife of their functions, and the circulation
proceeds as before. On the application of thefe princi-
Vol. XVI. Part II.
f Munienr-
bach's
Comp.
XT.
*54
Voice ot
birds.
, *55
Relations
of refpira¬
tion with
other func¬
tions.
O L O G Y.
5° 5
pies depends the recovery of thofe apparently dead from Of
afphjxia (liiffocation, drowning, &c.). When the cir-Re{Pir-it:ori;
culation becomes languid from indolence, from depref- '
fing paflions, or the w'ant of accuftomed itimuli, we feel
about the breaft a peculiar fenfation, which phylicians
call anxiety, and which is relieved by a deep infpira¬
tion } by fighing, yawning, &c. Violent exertions of
the refpiratory, organs, fuch as laughing, coughing,
finging, talking unufually long or loudly, quicken the
circulation, fometimes to an alarming degree, fo as to
occafion haemorrhage in fuch as are predifpofed to that
affedlion. Breathing in an atmofphere that is much ra¬
refied, as on the top of a high mountain, has often the
effedt of producing plethora and haemorrhage ; though
this, perhaps, is imputable rather to a want of the ordi¬
nary preflure on the furface of the body.
When the circulation through the lungs is impeded With fenfa-
or obftrudted, a determination of blood takes place to1'011*
other parts, efpecially to the head. The effects produced
on the brain and other organs of fenfation, by the
breathing of impure air, are dreadful. When the fame
quantity of air is repeatedly refpired, there is experien¬
ced, firlt, great anxiety about the breaft, and this foon be¬
comes intolerable 5 the face fwells, becomes livid, or
even black, and feels exceflively hot \ fparks of fire
feem to dance before the eyes j the fight becomes de¬
praved ; giddinefs, ringing in the ears, and confufion of
thought fucceed ; and if freili air be not foon fupplied,
the fubjedt of the experiment lofes both fenfation and
motion, and falls into a ftate refembling apoplexy 1
When rarefied air is breathed, the nervous fyftem expe- on.
riences a kind of excitement } agreeable fenfations are Death
produced, with a difpofition to mirth and cheerfulnefs ; p. 25.
but if the perfon continue for fome time in fuch a fitua-
tion, an unufual languor, heavinefs, and difpofition to
fleep, come on f. We need not here defcribe the plea-f Saujfure
furable fenfations excited by the refpiration of nitrous Voyage dam
oxide, as thefe have been already related under Chemi- les -Atpes,
stry, N° 366. The exhilarating effects which
pure and ferene atmofphere produce on the general fy¬
ftem, and the uneafy lenfations experienced under a
thick and clouded Iky, are partly referable to this head.
1 he nervous fyftem alio afts on the organs of relpira-
tion. In fome affections of the brain, refpiration is
much quickened, while in others, efpecially the coma-
tofe affe£tions, it is flow, laborious, and often attended
with that peculiar noife called Jlertor. It is well known
what effect anxiety, eagernefs, hope, or defire, have on
the refpiration. According as one or other of thefe
paflions is predominant, the breathing becomes hurried,
irregular, or fufpended.
An evident relation takes place between refpiration With ma-
and motion. The breathing is quickened by exercife jtion;
and when there is a confiderable debility of the mufcu-
lar fyftem, the flighteft exertion produces hurried refpi¬
ration, panting, &c. In thofe animals that poffefs the
greateft powers of motion, refpiration is moft free, and
the air moft extenfively diffufed over the body. In
birds, not only the lungs are very extenfive, but the air
is conveyed into the bones of the fkull, and into the
hollows of the larger cylindrical bones; and in inledts
which have the moft rapid motions, the air penetrates to
every part of the body. Motion, as well as fenfation,
becomes unufually free and vigorous in rarefied air, and
during the refpiralion of nitrous oxide ; while in cafes
3 S of
*59
With diaef-
506 PHYSIO
Of of impeded or obflructed refpxration, the atlion of the
R f fpiiation. mu{cjes is languid and feeble.. Indeed, if we may im-
y plicitly rely on the experiments that have been made on
the refpiration of de-oxygenated gafes, the mufcular
fibres are among the firit organs tnat are injured. \\ e
are told that by the admiiTioa of black blood, or blood
that has not undergone the neceffary changes by heal¬
thy refpiration, the mufcles lofe their power of contrac¬
tion, and even their irritability.
The organs and function of refpiration fympathife
with thofe of digeftion. When the former function is
molt free, the latter is generally molt healthy 5 the re¬
fpiration of pure or rarefied air, or of the nitrous oxide,
is attended with an increafe of appetite, and of the di-
geftive powers, as w*as experienced by M. Sauffure while
wandering among the Alps, and by Davy while relpir-
ing the gas of Paradife. Again, when digeftion is im¬
paired, or when the ftomach is overloaded, the breath¬
ing is rendered difficult, laborious, or irregular, and in
many cafes of affeftion of the itomach, cough is a very
common fymptom. Tliefe effects produced on the re-
Ipiratory organs in confequence of impaired digeftion,
are afcribable chiefly to the preffure on the diaphragm
by the diftended Itomach.
Many other relations might be pointed out between
refpiration and the other functions of the animal econo¬
my, but our limits do not permit us to enlarge further
on the fubjedt *. _ • _
^ ^ For an account of the morbid affections of refpira-
'phyjioL fur t*on, fuch as fneexing, hiccup, coughing, anxiety, dyf-
la Vie et la pnoca, or difficulty of breathing, fee the article Medi-
iy
* See Bi¬
chat Re-
Mort.
CINE.
Chap. IX. Of Nutrition and JJftmilatiorn
260
Nature of
nutrition.
261
Each athni!
peculiar
changes
LOGY. Chap. ia.
into chyle ; but if chyle, or what is very fimilar toil, OfNutri-^
frefti milk, be received into the ftomach, this organ
exerts on it the ufual change, and does not pafs it for- ‘ ^ 1 ^
wrard into the inteftines unaltered, though we know by
experiment, that frelh milk is capable of being taken
up unchanged by the abforbents of the bowels *. A- * Fordyce
gain, blood is always perfected within the circulating on Digef-
veffels ; and if chyle or frefti milk be injected into the^07Z»l>’I*£'
arteries, it produces dangerous effects, while the frelh
blood of another living animal may be transfufed into
thefe veffels without injury. In like manner, if a piece
of frefli mufcular flefh be cut from a living animal, and
applied to the mufcles of another living animal, alfo
newly divided, the tw’O parts unite, and are immedi¬
ately aflimilated j and even frefti bone may, in the fame
manner be ingrafted on the living bones of the fame, or
of a different fpecies of animal f j w hile fubftances |
that are foreign to the nature of the animal body, when Mag. \u
introduced into the blood-veffels, prove fatal, and wfien 308.
inferted into a wounded mufcular or bony part, prevent
the wound from healing
The funftion by which the nutritious particles re¬
ceived by a living being are aflimilated to the nature of
that being, or become part of its fubftance, is properly-
called nutrition. This is the completion of the proceis
which, in moft animals, is the combined refult of. feve-
ral other operations. ’I bus, in the fuperior animals,
from man to the mollufca, the whole procefs of nutrition
confifts of digejlion, abforption, circulation, and refpira-
tkn ; by the two laft of w hich the nouriftiment received
is changed into perfect blood, and fitted ior the lupport
and renewral of the feveral parts of the fyftem. F.cm
the account of the conftituent parts of the blood given
under Chemistry, N° 2660, it will appear, that this
fluid contains within itfelf the principles of which every
part of the body is compofed. Thus it contains f brine,
which is the chief principle of the mufcular parts; phof-
phate of lime, which forms the bafis of the bones •, albu¬
men and gelatine, the chief conftituents of cartilages,
ligaments and tendons, &c. Thefe principles are con¬
veyed by the arterial blood, during its circulation, to
thole parts of the fyftem where they are required, for
renewing wafte, or fupplying deficiencies, and thus they
are aflimilated to the nature of the body.
The powTer of affimilation, fo remarkable in living
latingorga, bodies, is not the fame in every aflimilating organ}
produces eP.cH fias the property of converting the materials it
receives (provided they be fulceptible of this converfionj
into a peculiar fubftance. Thus, the ftomach always
converts the food into chyme; the inteftines change it
Thtfe chcumftances ihow that affimilation is a che-^flimila-
mical procefs, though modified and regulated by the tion a che-
aflion of the living principle. The chemical nature ofmieal Pr°-
aflimilation is molt dillin&ly proved by the well-knowncefs*
experiment of colouring the bones of an animal, by
feeding it on madder. The particles of the madder,
which wTe knowr to have a ftrong affinity for phofphate
of lime, are carried unchanged from the ftomach into
the blood-veffels, and are thence conveyed, probably in
combination with the phofphate of lime there contained,
into the fubftance of the bones, where they are depo-
fited, and remain for a confiderable time.
We have confidered nutrition as performed by the Nutrition
circulating veffels. It has been fuppofed that the nerves n°t per-
are the organs of nutrition ; but this ftrange hypothefis by
is completely overturned by an experiment of the fecond
Monro, which proves that the limb of a frog may be
preferved alive and nouriihed by the blood-veffels, after
its communication with the brain has been cut off by
dividing the nerves. _ 264
In infefts and zoophytes, where there are no circula- Nutrition
ting veffels, nutrition muff be a very fimple operation, in infedbs
According to Cuvier, it is performed by imbibition ; the ft*
pores of the animal’s body receiving immediately the "
nutritious fluids on which it feeds. 465
In plants and animals, the aflimilating power has al-Aflimiiat-
wTays certain limits preferibed to it 5 its influence is very ^
generally confined to the fort of food congenial to the
fpecies, and its ftrength is varied according to eircum-
ftances, as the age, the habits, and the flate of health.
Thofe which are young aflimilate fafter than thofe
which are old 5 and one fpecies, which may partly be
ownng to the nature of their food, will affimilate much
fafter than another. Certain worms that feed on ani¬
mal and vegetable fubftances will, in twenty-four hours
after their efcape from the egg, become not only double
their former fize, but will weigh, according to Redi,
from 155 to 210 times more than before. Moft oils
are of very difficult affimilation j and thofe which are
volatile will often refift the long-continued and the
varied aftion of the living organs; will mingle with the
parts, and, undecompofed, communicate their flavour.
Other circumftances refpe£Ung nutrition have been
noticed
Chap. X.
Of noticed in the firft part of Akatcmy, N° 130 ; and
t Secretion chemical doctrine of aflimilation is more fully con-
" v" lidered under Chemistry, N° 2576—2571.
PHYSIOLOGY
while it at the fame time feparates and diftinguilhes
507
Of
Chap. X. Of Secretion.
266
Secretion. That function by which any organ, or fet of organs,
feparates from the general mafs of blood certain prin¬
ciples intended to perform fome important office in the
animal economy, is called fecretion ; and the fubftances
2(5^ io feparated, are called fecretions.
Organs. The fecretory organs in the more perfeef animals are
very numerous, and fome of them very complex. The
molt fimple of them feem to be the cellular texture, and
the mucous membranes. The next in fimplicity are
the conglobate glands, and perhaps the fpleen, while
the more complex organs are the liver, the tejlicles, the
atrabiliary capfules, 6i.c. An account of all thefe or¬
gans, as they occur in the human body, has been given
in the firft part of the article Anatomy j and the cor-
reiponding organs of the inferior animals, with others
not found in man, are deferibed by writers on conspara-
tive anatomy, efpecially Cuvier and Blumenbach.
Kinds of 4- Secretion appears to be of three kinds: 1. Tranfuda-
cretion. non, in which the fecreted matters merely ooze through
the pores of the fecreting organ. This takes place in
the loweft claftes of animals, as in zoophytes, infedls,
and fome worms, but rarely in the human fubjeft.
2. Exhalation, in which the fecieted fluids are poured
out into cavities by certain branches of the arteries with
open mouths, called exha/ants. This appears to take
place in many organs of the moft perfeft animals, efpe¬
cially from the mucous membranes, the fynovial glands,
&.c. 3. Secretion, properly fo called, in which the
blood paifes through glandular bodies, where a part of
it is decompofed, and carried out in another form by
particular tubes called excretory duEls. This is the
cafe with moft of the fecreting organs, as the falivary
glands, the lachrymal glands, the liver, the pancreas,
2(jp the tefticles, and a few others.
Secreted The fecreted fluids are chiefly the following : lymph,
matters, fei'um, tears, mucus, faliva, pancreatic juice, gajlricjuice,
enteric juice, bile,femen, fynovia,fat, marrow, cerumen
or ear-wax, and in the female, milk. The other mat¬
ters fecreted, which may rather be termed folid than
fluid, are albumen, gelatine, f brine, and phofphate of
lime. On the nature and properties of all thefe fub¬
ftances, fee the article Chemistry, Chap. xix. fe<ft. 3.
With refpeft to the fecretions in general, we may re¬
mark, that they are confiderably influenced by age, fex,
various affe£tions of the mind, and various bodily dif-
Senend ea^es- They are formed by organs which are fometimes
modifka- capable of fupplying the deficiencies of each other ;
tions of fe- they are fubje&ed to the influence of the atmofphere,
cretion. and to the temperaments of the body ; they are fome¬
times mixed together, and by this combination their na¬
ture is changed.
We (hall now briefly examine the adlion of three of
the fecreting organs, viz. the cellular membrane, the
liver, and the fpleen.
A&ion^f From the extenfive diftribution of the cellular mem-
the cellularhrane it is reafonable to conclude, that it is intended to
membrane, perform feveral important offices in the animal economy.
One of its raoft obvious ufes is to form a general con-
neifting medium between every part of the ftruflure.
every organ. From its eiafticity, and the lubricating Secretion,
fluid which it holds within its cells, it facilitates motion, V"“""
and thus affifts the adlion of all the mufcular parts and
organs. That it is i'ulceptible of great dilatation is
proved by the phenomena of analarcous dropfy ; and the
gradual evacuation of the water when anafarcous limbs
are pundlured, as well as the paffage of extraneous
bodies below the Ikin from one part to another, feem to
Ihow that ,it poffeffes confiderable. contra&ile powers.
It is chiefly, however, as a fecreting organ that we are
here to confider the cellular membrane ; and in this way
its function is of the utmoft importance. The fatty
matter, that is fo copious in moil of the fuperior ani¬
mals, is contained within particular cells or bags of the
cellular membrane, and is found in greateft quantities
below the Ikin, efpecially on the fernal part of the
belly, and about the kidneys. In fome animals, as the
hog, the feal, the walrus and the cetaceous tribes, it
forms a layer feveral inches in thicknefs, and in all the
water animals above mentioned it is nearly fluid. To
thefe animals it not only ferves the purpofes of a warm
covering by the flownefs with which it condufts heat j
but, by diminifliing their fpecific gravity, renders their
motions on the furface of the'water much more eafy
and expeditious. One of the moft important ufes of the
fat feems to be to fupply nouriflnnent to the body, when
the ordinary channel is obltrufted, or the lyftem render¬
ed incapable, from torpor or difeafe, of receiving food.
When fat perfons are attacked by fever, or fimilar acute •
difeafes, they become emaciated, fometimes to fo great
a degree as to appear a mere (keleton j and thofe" ani¬
mals who fleep during winter, though very fat when
they retire to their dormitories, are extremely lank and
lean when they quit thefe on the return of fpring. In
all thefe cafes the fat alone is abforbed, and fupplies the
wafte that takes place in the body, and would other-
wife prove fatal.
On the attions of the cellular membrane, fee Bichat,
Anatomic Generale, tom. i.
Some phyfiologifts have fuppofed that the bile fecret- Region
ed by the liver is not formed entirely from the blood of the Hver.
the vena portarum, but partly from the hepatic artery.
Dr Saunders, who has examined the arguments in fa¬
vour of this fuppofition, decides againft it, and confiders
the ufual opinion of the bile being folely fecreted from
the blood of the vena portarum, as quite fatisfadlory.
It has alfo been fuppofed, that the whole of the bile Is
not fecreted by the liver, but that the gall bladder has
a (hare in this office, and is not merely a refervoir, like
the urinary bladder. This fuppofition is highly improba¬
ble, although we think there can be little doubt that
the bile undergoes, within the gall bladder, fome pe¬
culiar changes, which render it better fitted for the
functions it has to perform. We know that the gall
bladder is very mufcular, and that there is an appear¬
ance of follicles within it. It is therefore probable
that fome matter is fecreted from its internal furface,
which produces a neceflary change in the bile.
The principal ufe of the bile feems to be to ftimulate IKes of the
the inteftines, and thus keep up their energy and peri- bile,
ftaltic motion, though it is probable that, befides this
office, it performs feveral others of importance in the
animal economy, fuch as affifting in the decompofiticn
of the food, and thus forming chyle; and acling as a
3 $ 2 general
So3
dfrj on the
Liver.
274
yfes of the
fpieen.
P H Y S I
Of general ftiumlus to the fyftem. That it has this lafl
Secretion. ei]'cQ- Js probable from the torpor, inactivity, and de-
*“ v — jC(c^on t}iat attend hypochondriacal and chlorotic af¬
fections, in which this lecretion is defective. 1 oo great
a fecretion, or rather excretion of bile, is attended with
* See SUun- violent purging *.
On the nature of the bile, and biliary concretions,
fee Chemistry, N° 2664.
Few iubjeCls in phyfiology have given rife to more
difcuflion, and few have been coniidered with fo little
fuccefs, as the ufe of the Ipleen in the animal economy.
That an organ fo large, and io well fupplied with blood,
fhould be intended for iome important function, is Icarce-
ly to be doubetd 5 and yet the inftances of animals that
have lived, feemingly with little inconvenience, after the
fpleen had been cut out, feem to prove that this organ
is not of i'uch great importance as it appears to be. 1 he
conjectures refpeCling its ufes are various, and fome of
them, not a little ludicrous. Some have fuppofed that
it aided by its weight and preffure on the ftomach, and
thus promoted digeftion at one time, and counteracted
hunger at another j fome, that it was intended to dilute
and attenuate the blood; others, to deprive that fluid of
its fuperabundant oil; another party, that it contributed
to form the red globules of the blood 5 and fome of the
older phyfiologifts fuppofed that it fecreted that fluid to
Opinion of which they gave the name of blach bile. Dumas is of
Dumas. opinion that it is a fort of fupplementary organ, both to
the liver and the kidneys, feparating from the blood part
of its feroflty, and then delivering it over to the liver in
a proper ftate for the formation of bile ^ and furniihing
to the kidneys another portion of lerolity to form the
* Principes via.te.iy part of the urine*. That at leaf! a part of thefe
de Phyfiol. opinions of Dumas has fome foundation, will appear from
the following fummary of the late experiments of Mr
Everard Home.
Profecuting the inquiry refpe&ing the ftate of the
ftomach during digeftion, which we have formerly al¬
luded to (fee N° 161), Mr Home found that during di¬
geftion, the fluids taken into the ftomach are principally
contained in the cardiac portion ; and he inferred, from
the uniform conftftence of the chyme in the pyloric por¬
tion, that a great part of the fluids are carried out of the
ftomach without ever reaching the pylorus. As he con¬
ceived very naturally, that the lymphatics of the fto¬
mach were inadequate to this office, he conje&ured that
the fluids might pafs off by the fpleen. He proved, by
a decifive experiment, that liquors might pafs through
the ftomach without going through the pylorus, and he
alfo found at the fame time, that the fpleen was turgid,
Unufually large, and its external furface very irregular •,
and wThen cut into, fmall cells were every where met
with, containing a v7atery fluid, and occupying a confi-
derable portion of its fubftance. Rudiments of thefe
cells had been feen before by Malpighi, who confidered
them to be glands, and by Cuvier, who calls them cor-
pufcles ; but the cells in a diftended ftate feem not to
have been examined till Mr Home was led to look for
them, in confequence of the above experiment. Mr
Home varied this experiment, by giving animals a de-
eoftion of madder, and an infufion of rhubarb, and obtain¬
ed fimilar refults. Part of the fluid fwallowed was again
rejected by vomiting j but of that which remained it was
always found that a. part had efcaped, wdthout any pof-
fibility of paffing by the pylorus, as this was fecured by
tom
592*
976
Experi¬
ments of
A'lr Home.
O L O G Y. - Chap X.
ligature. It did not probably efcape by the abfbrbents, Of
as thefe were not ib much dillended by fluid as to be Secretion.
viftble \ and it certainly did enter the fpleen, as there
wTas there found a quantity of liquor, which w as proved,
by an alkaline left, to contain rhubarb. A large quan- * Phil.
tity of urine was found in the bladder, alfo impregnated ^'Ufts‘ for
•ill-. ^ e> iSgs, p. 2.
with rhuoarb *.
brom thefe experiments it appears, that the fpleen is Spken car-
capable of carrying off from the itomach, a part of its fits off fluid
fluid contents, thus affording a much nearer paflage to f‘om tl,e
the bladder than through the abforbents. If this invef- lwI1“lc ''
tigation,on further trials, ihall prove equally fatisfablory,
it will explain why the bladder is often diftended wadi
urine in a fliort time alter drinking} and will do away
the neceflily of having recourle to the difputed hypo-
thefts of the retrograde ad ion of the abforbents.
In the inferior claffes of animals there are a number pCCuifar
of peculiar i'ecretions, which, from their utility in medi- animal fe-
cine or the arts, or from their noxious or unpleafant ef-cretions.
feels, are deferving the attention of phyfiologiits. We
can here only mention a fewr of the more important.
The nature and properties of moft of them are explained
under Chemistry.
Some of the mammalia fecrete matters that have a
very ftrong fmell, as vujli, civet, cajlor, and-in particu¬
lar the fluid emitted from the hide of feveral of the
weazel tribe, befide the civet cat. Ambergris is fecret¬
ed by fome fpecies of whales. Birds, elpecially waiter
fowls, fecrele a large quantity of oily matter, which they
ufe in drefling their feathers. Some reptiles, efpecially
the toad, fecrete an acrimonious fluid, which feems to
ferve them as a weapon of defence. Many ferpents, as
is well known, produce a moft virulent poifon, which
they infert into the wounds inflidled by their fangs.
Some fifties fecrete fluids of a fimilar tendency. Few
animals, however, form fecretions fo various and fo uf'e-
ful, as the iniedt tribes, from whom we procure cochi¬
neal, kermes, Lac,fdk, occ. Some of the mollutca, as the
mufcle, and the fpinning flag, alfo fecrete a matter fimi¬
lar to filk, by means of which they either fecure them-
felves firmly in their fituations, or facilitate their pro-
greflive motion. The ink of the cuttleJijh, fuppofed
w ith no fmall probability, to be the bafis of Indian or
Chinefe ink, is alfo a remarkable animal fecretion, which
feems intended by nature to fereen the animal, and af-
fift it in eluding the vigilance of its purfuers.
There are alfo many important vegetable fecretions, Vegetable
conftituting what are called gums, rejins, and gum-ref,ns; fecretious.
as gum arable, gum-dragant; guaiac, dragon's blood;
ajfafoetida, gamboge, myrrh, aloes, and many others; for
an account of which fee Chemistry and Materia
Medica.
Chap. XI. Of Excretion.
280
The fundlion of excretion differs but little in its na-Excraio*.
ture from that of fecrelion already confidered. As the
organs of fecretion feparate from the blood thofe fub-
ftances wftiich are ufeful in the animal economy, fo the
excretory organs feparate from the blood, or from the
food taken into the ftomach, thofe fubftances which are
to be conveyed out of the body as excrementitious, viz.
the folid excrement, the urine, and perfpiratioru 5jr
The organs of excretion, then, are chiefly the bowels, Organs^
efpecially the larger inteftines, the kidneys, with their
appendages,
Chap. XD P H Y S I
Df appendages, tKe ureters and urinary bladder, and the
Excretion. For an account of thefe in the human body, fee
^ Anatomy, Part I. j and for the varieties of thefe or¬
gans in fuch of the inferior animals as poiTels them, and
for the means by which their abfence is fupplied in
others, fee the works of Cuvier and Blumenbach already
2S2 quoted.
Excretion f he phyfiology of inteftinal excretion requires little ex-
by the intef-planatioii. The remains of the food, after the nutritious
t-iues. chyle has been extracted from it by tire lafteals, are car¬
ried onward through the colon and redlum by the pe-
riftaltic motion of the inteftinal canal, excited to adlion
by the ftimulus of their contents, and of the bile, and
aflifted by the prefture of the abdominal mufcles, till
they reach the extremity of the redlum, when becoming
more itimul nt, partly by their bulk, and partly by their
increafed acrimony, they roufe the mufcular fibres of that
inteftine to greater adlion, fo as, with the afliftance of
the abdominal mufcles, to overcome the refiftance of the
fphinttet', and are thus expelled.
Relations. Inteftmal excretion is influenced by moft of the pre¬
ceding fundlions. I. By the nervous power j as we find
that in cafes of paralyfis, the excrements are not paffed
without artificial means, or they are voided involuntari¬
ly. 2. By motion. Thus wre find that the adtion of
the bowels is increafed by exercife, and leflened by in¬
dolence and a fedentary life ; though the quantity of
excrement paffed is greater in the latter cafe than in the
former, (hewing that the ftimulus of the excremcntitious
matter is not fufficient without mufcular adfion, to pro¬
duce the regular performance of this fundtion. 3. By
digeftion. It is well known that the ftronger the digef-
tive powers of the ftomach, the more adlive are the
bowels, and again, when thefe latter are overloaded with
excrement, the fundlions of the ftomach are difordered.
4. By fecretion. The adfion of the inteftines is increaf¬
ed, when that of the fecretory organs which pour their
contents into the alimentary canal, becomes unufually
great, viz. in unuiual fecretions of bile or mucus, as in
cholera and diarrhoea; while, when thofe fecretions are
defedlive, as in cafes of jaundice, the inteftines become
unufually torpid.
. The morbid affedfions of inteftinal fecretion have been
’Excretion confidered under Medicine, N° 109—112, and 114,115.
by the kid- T he organs deftined for the excretion of urine afford
«eys. the moft complete apparatus for this fundlion of any that
we lhall l^ave occafion to notice, confifting of an affem-
blage of glands, colledled within one membrane 5 an ex¬
cretory dudl ; a refervoir for colledling the excreted
fluid, and a canal for conveying it out of the body. In¬
deed we may confider the kidneys rather as fecreting
than excreting organs, as the urine there formed differs
fo much in its nature and properties from the circulating
fluids. We know, by a decifive experiment, that the
kidneys perform the whole of this office, and that the
other organs are intended for the excretion of the urine ;
for when the ureters are tied or obftrufted next the blad¬
der, we find that the fecretion of urine flill goes on, and
that the ureters above the obftruftion foon become filled
and prodigiouffy diftended.
I he nature and properties of urine, in its natural ffate,
and as altered in certain difeafes, have been confidered
under Chemistry, N° 2670.
As the urine contains two fubftances that are not
found in the blood, viz. urea and uric acid, Dr Thom-
O L O G Y. 50y
fon concludes, on very probable grounds, that the office
of the kidneys is not merely to feparate from the blood, £'xc:et‘on,j
a quantity of water and falts, but that they exert on this | j}j0ri.
fluid fome peculiar adlion, decompofing fome part of the fan's Che-
blood, and forming fomc new fubftance or fubftances f. viijlry, yol.
The mutual relations between this excretion and the v' 5^ ePlt*
preceding fundHons, are not many, or very important./425k
During certain affcdlions of the nervous fyftem, there is a Relations.
hidden and copious excretion of limpid urine, and fome
mental emotions produce an involuntary flow of it J. j Mer-
And in cafes of palfy, an incontinence, or a total fup- chant of
preffion of urine, is very common. This excretion emce, ^
A ' “ • • • • 1 v« icciic 1.
confiderably influenced by motion, being lefs copious m
thofe who ufe much exercife, or lead a laborious life.
The morbid affedfions referable to this excretion, are
noticed under Medicine, N° 118—122. 28(J
The excretion by the fkin, or peifpiration, has exer- Escret;0n
cifed the ingenuity of many phyficians and phyfiologifts, by the fkin.
ever fince the time of Sandforius; and though it is not
now confidered as fo eflential to life and health as it was
in the beginning of the 18th century, is certainly of
great importance. The quantity of watery fluid occa-
fionally thrown out by the fkin in the form of fweat,
proves that, by means of this organ, the blood is freed
from a great deal of ufelefs or perhaps injurious matter,
which could not fo conveniently, or fo perfedfly, be ex¬
pelled by other outlets. The nature of the matter per-
fpired, and the quantity of ordinary perfpiration, have
been inveftigated by many able experimentaliifs, the re-
fult of whofe labours is given in the firft volume of John-
fon’s Animal Chemijlry ; the fifth volume (third edition)
of Dr Thomfon’s Si/Jlem of Chemijlry ; in a paper by Dr
Kellie in the i'econd number of the Edinburgh Me¬
dical and Surgical Journal, and in our article Chemistry.
The principal fadls that have been afeertained with
refpedt to the perfpirable matter thrown out by the {kin,
relate either to its quantity, or its chemical compofition. ^
I. The experiments on the quantity perfpired, on Quantity of
which we can the moft rely, are thofe of Lavoiffer, Se- the perfpi-
guin, and Mr Abernethy. From thefe experiments vveiat*on‘
may deduce the following conclufions : 1. The great eft ■
quantity of matter perfpired in a minute, amounts to
about 26 grains troy, the leaf! to about 9 grains; giv¬
ing an average of about 17 grains in the minute, or
about 52 ounces in 24 hours. Dr Kellie eftimates the
quantity at about 30 ounces, which feems too fmall. 2.
The quantity of perfpiration is increafed by drink, but
not perceptibly by folid food. 3. Perfpiration is the
leaf! in quantity immediately after a meal, and reaches
its higheft proportion during digeftion.
II. The perfpirable matter is chiefly compofed of a Its C(j^8 ^
large quantity of water, fome carbon or carbonic acid, tion. F ^
a fmall quantity of another acid, fuppofed to be the
phofphoric, and a peculiar oily matter of an odorous
quality, differing in different animals, and, as it fhould
feem, in different individuals. The perfpiration of qua¬
drupeds is frequently found to contain phofphate of lirne,
and fometimes urea. See Chemistry, N° 2532.
As to the relabons of perfpiration with the preceding
funefions, we may remark that this excretion is in¬
creafed by various paffions of the mind, by exercife, by
healthy and rapid digeftion ; that it is generally in pro¬
portion to the vigour and quicknefs of the circulation
and refpiration, and that it is capable of fupplying the'
defeat of the two former excretions. On the contrary^
5io
P II Y 3 I
Of Integu- it is lelTened by inafUvity j by tbe impaired ftate of the
. niat1' ' digeftive organs ; by languid circulation and refpiration,
and by violent purging, or evacuation of urine.
Chap. XII. Of Integumation.
ZQO
Ufesofinte- All living bodies are furnilhed with integuments,
gup. nts as -^-Ixich are intended to afford them a defence againft
etence. thofe injuries to which their fituation is commonly ex-
pofed. Of the integuments fome are ufeful in prevent¬
ing the diflipation of the fluids ; fome in refilling acrid
and corrofive fubilances j fome of them are indigeflible
in the ffomach of animals, and fome appear to be incor¬
ruptible in the earth. By thefe properties, feeds and the
ova of infefls are preferved for a confiderable time, wait¬
ing the changes of foil or of feafon that are favourable to
their evolution. They are protedled from the action of
weak membranous flomachs, and thus the animals who
may fwallow them contribute to their propagation. It is
thus the feeds of the mifletoe are difperfed, and depofit-
ed on the bark of the oak or the afh. There is a gela¬
tinous fubftance frequently ejefted by birds, and com¬
monly called tremella, nq/Ioc, or liar-fall, which Dr Bar¬
clay has proved to be nothing elfe than the ovidudls of
frogs, which, as the embryo in form of an egg, moves
along their winding canal, fecrete that tranfparent and
r ifcid matter which conflitutes the’albuminous part of the
ovum, and feeds and protects the embryo while in wa¬
ter.
The moil important circumftances with refpedl to in¬
tegumation relate to the varieties of the integuments
themfelves, and to the changes or renovation of thefe in
different animals.
Integu- I. Some integuments are ufeful, chiefly from their
ments ufe- flrength and hardnefs. The elytra or fhelly coverings
ful by their of beetle tribes afford an excellent defence for their
hardnefs; niembranous wdngs, when folded up j the (hell of the
In ail lodges the inteflines, when the animal comes forth
to fearch for food, and affords a fafe retreat to the ani¬
mal, when it is threatened with any danger from with¬
out. The fhells of fome animals can be opened and
clofed by a mufcular powder ; and fome of them, as in
the tail of the lobfler, are fo difpofed in plates or fcales,
as to be no hindrance to the animal’s motion. Several
infects which pafs a part of their time in the W'ater, al¬
ways compofe for themfelves a fhell, where it is need¬
ful.
l>y their ex- Some integuments are covered with feathers, fome
ternal co- with hair or thick down. Befides many other obvious
vering; ufes of thefe coverings, they generally ferve to repel in¬
fers •, and being bad condudtors of heat, tend to pre-
ferve an equal and neceifary temperature. Some inte¬
guments are covered whh prickles, which oppofe the at¬
tacks of an enemy by the ftrength of their points, or by
the venom which they infufe, as in the flings of nettles,
and the down of fome other plants, and fome infcdfs.
Others again are moiftened by a vifcid fecretion, which
preferves the neceflary foftnefs of the parts, prevents
evaporation, refills acrimony, enables fome beings. to
deltroy their enemies, and aflifts others in performing
293 their progrelfive motions.
by their ef- Both plants and animals, but particularly the former,
flu via; are 0ften protect ed by odorous effluvia from their inte¬
guments. Thefe effluvia are the finer parts of their vola¬
tile oil. always inflammable, and fo fubtile, that the
4
O L O G Y. Chap. XII.
continual emifflon of it from wood or flowers does not Oflntegu-
fenfibly diminifh their W'eight. To this fragrance it is n‘atlon
owing, that the deadly nightfhade ("atropa belladonna\
the henbane, hounds-tongue, and many others, are feen
on alffioit every high road untouched by animals. The
manchinelle-tree of the Weft Indies emits fo very dan¬
gerous vapours, that the natives poifon their arrows with
its juices, and thofe have died wTho have ventured to deep
under its lhade. The lobelia longifiora of America pro¬
duces a fuffocating oppreflion in the breaft of thofe w ho
refpire in its vicinity. The return of a periodical difor-
der has been attributed to the exhalation of the rhus
toxicodendron. Of all the vegetable effluvia, however,
that afford defence to the plant from which they pro¬
ceed, or annoyance to the animals that approach it,
none are equal to thofe of the celebrated bohun-upas, or
poifon-tree of Java, whofe exhalations have been laid to
extend to the dillance of feveral miles, preventing all
accefs of animals, or punilhing the intruders with ccr- * See p- j
tain death. It is rather unfortunate for the botanical kerten's
poets, that the eftedls of this poifon have been <gre&\\y Ge graphy,
exaggerated, if indeed fuch a marvellous tree really ex-''Tmer Ja~
ills *. w‘
Various colours of the integuments afford a fpecies offcy iheir co«
defence. Caterpillars which feed on leaves are general-lour,
ly green •, and earth wrorms the colour of the earth
wfflich they inhabit. Butterflies which frequent flowers
are coloured like them. Small birds which frequent
hedges have greenilh backs like the leaves, and lights
coloured bellies like the Iky, and are hence lefs vifible
to the hawk wrho paffes under them or over them.
Thofe birds which are much amongft flowers, as the
goldfinch, are furnilhed with vivid colours. The lark,
partridge, and hare, are of the colour of dry vegetables,
or earth on wrhich they reft; and frogs vary their colour
with the mud of the ftreams which they frequent, and
thofe which live on trees are green. Fifh which are
generally fufpended in the wrater, and Swallows which
are generally fufpended in the air, have their backs the
colour of the diftant ground, and their bellies of the
Iky. The fphinx convolvuli, or unicorn moth, refembles
in colour the flower on which it reffs j and among
plants, the neftary and petals of the ophrys, and of
fome kinds of the delphinium, rcfemble both in form
and colour the infefls which plunder them, and thus
fometimes efcape from their enemies by having the ap¬
pearance of being pre-occupied. From colour being
thus employed as a defence, many animals vary their
colours with the feafons and circumftances ; and thofe
which are of different colours in fummer according to
the places which they inhabit, in wfinter aflume in com¬
mon the colour of the fnow. ' *95
II. The changes that take place on the integumentsC5ianSe ^
confift either of a partial,4 or complete, renewal of^^"
them. As the more fuperficial integuments are com¬
monly infenfible to ftimuli, and pofleis little or nothing
of the vital principle ; in all cafes where they cannot be
enlarged to admit of an additional increafe of growth,
or, where they are not furniffled with organs for re¬
pairing thofe injuries which they may fuffer from acci¬
dent or difeafe, the body is endowed by nature with
a power of throwing them off, and of producing others
in their Head. Thus, ferpents and toads Hough their
fkinsj the oruftacea caft their fhells ; the larvae of in¬
fers change their cuticle j and feveral trees, efpecially
the
Chap. XIII.
PHYSIOLOGY.
5 IT
Of Trans- the cork tree, throw off their outer bark. Even man
formation, generally changes the cuticle, which peels off
w form of fcales. Moft animals once a year change
their hair, wool, or feathers, and have thefe renewed
by a frefh covering j a procefs w7ell known by the name
of moulting. Some animals wrho do not ufually caff
their external covering, have the power of repairing this
when injured. This is the cafe with molt of the teftacea,
efpecially fnails.
Chap. XIII. Of Transformation,
Transfer- The alterations which organi-zed beings undergo from
oiation. metamorphofs or transformation, are more ftriking than
thofe which we have delcribed in the preceding chap¬
ter. It has indeed been afferted, that thefe alterations
conlift in throwing off certain temporary coverings j but
this expreffion is inaccurate, and arifes from a w7ant of
precilion of ideas. Transformation and change of in¬
teguments are really different; the truth is, transforma¬
tion often takes place without any change of integu¬
ments, and there is often a change of integuments with¬
out any change of form. This new form is fometimes
occafioned by a change of lhape, confiftency, and colour,
as when the lobes of a feed are converted into feminal
leaves. It is at other times occalioned by a change of
proportion among the parts, and at others by the addi¬
tion of new7 organs, as when the emmet receives wnngs,
and the plume of the feed is fed by new roots ftriking
into the ground : or, laftly, it is occafioned by a change
in the form and organs, and in their mode of operation,
as happens in a remarkable degree to feme infe<fts. In¬
deed, though all living bodies, both plants and animals,
undergo feme degree of transformation in the courfe of
their exiftence, thefe changes are moft remarkable in in¬
fects.
Transfor- Many reptiles undergo very curious changes, but thefe
mationof are moft remarkable in the frog tribe. The larva or
teptiies; tadpole, as it is called, of the frog, is an animal with a
large head, a long tail, no limbs, and commonly poffef-
fed of gills, all obvioufly very different, both in form,
proportion, and ufes, from the parts of the perfeft ani¬
mal. The curious appearance of w7hat has been confi-
dered as the tadpole of the rana paradoxa, has led fome
naturalifts to deferibe it as an animal of a different ge-
29S nus’ e’t^ler or a Iizard } fee Erpetology, p. 284.
of infedts. Many infefts appear to coniift of two diftindt animal
bodies, one within the other; the exterior, a creature of
an ugly form, refiding in the w7ater, or under the earth,
breathing by gills, or fometimes by tracheae projecting
from the tail, pofieffing a voracious and grovelling ap¬
petite, and having a fvftem of fanguiferous veffels that
circulates the blood towards the head. When all its
parts decay and fall off, the creature inclofed fucceeds
in its ftead : this often is an animal of a different form,
generally lives in a different element, feeds on a diffe¬
rent fpecies of food, has different inftruments of motion,
different organs of fenfe, different organs of refpiration
and differently fituated } and being endowed with the
parts of generation, inclines to gratify the fenfual pro-
penffty, and produces an embryo, which becomes like
the firft, and from which, in procefs of time, a creature
is evolved fimilar to the former.
If the cm! ryo or egg be depofited on a leaf, the leaf
is frequently obferved to bend, to wrap it in folds, in¬
tended for the purpofe of pro testing it from injuries Of Trans-
and danger. If depolited in the body of an animal or formation.^
plant, they accommodate themfelves to its wants and '~"v
neceflities, and furnilh a tumor which ferves it for a
nidus, and befides, like an uterus, fupplies it with nouriih-
ment j and if depofited in the body of an infect, the
creature provides for the future deftination of its young
charge with all the tender care of a parent, and then
dies. 399
Thefe circumftances, added to the great variety of P*rents
forms which infers affume, render it fometimes difficult
to know who is the parent. We cannot, for inftance, diftinguith-
pronounce with certainty who is the true parent of the'ed.
gordius, known by the name of the feta equina, or hair
eel. A fet of experiments which Dr Barclay once be¬
gan with a view to throw fome light on the fubjeft,
were unfortunately interrupted by an accident. He
learned only, from a number of obiervations, that certain
black beetles, at the end of fummer, have the ftrongeff
propenfity to run into the water, where they foon die
and that one or twro, and fometimes three or four of
thofe eels gradually drop from the beetle by the anus.
Whether other infe&s provide for the gordius in this
manner, w7e have not yet been able to determine. 300
In all living bodies poffeffed of a fenforium, the changes Transfor-
of form, as well as the changes of habit and ofage, are ufu- mat‘on ac“
ally accompanied with new propenfities, appetites, and j-omPamc^
paffions. ... of propenfi-
Microfcopic obfervations having demonftrated, that ties,
all the forms of the plant and animal exifted previouffy 301
in the feed or embyro j transformation muft be owing
entirely to the evolution of the different parts by means tjon'0f
of nutrition. parts.
What nature intends by transformation, w7e cannot 302
determine ; but by means of it different elements areIts ufes
peopled, the different feafons varioufly adorned, and ani¬
mated nature wonderfully diverfified without a multipli¬
cation of beings.
Chap. XIV. Of Reproduction.
y
303
In the prefent chapter w7e ftiall notice, firft, the par- Reproduc-
tial reproductions that take place in fome claffes of aiti-ftonofpartsi
mals, and then take a general comparative view of the
principal phenomena of generation, in the various claffes
of living beings.
Experiments have proved, that even in the fuperior In mar^andt
claffes of animals, many parts of the body, wffien de- mammalia*
ftroyed or removed, may be reproduced. A bone may
be broken in fuch a manner, that part of it muft be
taken aw7ay, but in a few7 weeks the feparated ends are
brought together by the fecretion of new bony matter,
called callus. Little more than 24 hours have elapfed
after a fradure, before nature begins her operations. The
foft parts inflame ; the periofteum becomes fwelled 5 the
veffels pour out coagulable lymph, and a pellucid, gela¬
tinous fubftance appears about the broken extremities of
the bone. Into this minute blood-veffels are gradually
fent off' from the arteries, and in no very long time phoff
phite of lime begins to be fecreted, for rendering the
w'hole firm and compaCL In cafes of necrofs, where the
old bone entirely lofes its vitality, new bony matter is fe-
cretedinto the furrounding periofleum, which thickens and
enlarges, and in time fupplies the place of the old bone.
When a mufcular part is cut away, as in removing flelh .
that7
512
Of Repro-
cltuftion.
* Phil.
Trans.
■{• Jones'1!
Trehtife on
Hcetnorrha-
ges. Sec.
3°S
Reproduc¬
tion ofparts
in the infe¬
rior ani¬
mals;
306
in reptile';
.307
in crufta-
cea;
P II Y 3 I
tliai has become gangrenous, if the healthy funclion of
the furrounding parts can be re'fored, and the lofe or
fleflt has not been too great, the wound gradually fills
up, not indeed with tlelhy fibres, but with granulations
very much refembling the ordinary cellular fubfiance.
It is well known, that the hair, nails, and fkin, are oc-
cafionally renewed ; but it will appear extraordinary
that blood-vell'els, and even nerves, have been reprodu¬
ced. In cafes of aneurifm, where the trunk of the dif-
eafed artery is divided, fo as to cut off the ufual channel
for tire blood, the anaftomofing branches become gra¬
dually enlarged, and even new branches appear to be
formed for carrying on the circulatidn. What has been
faid above refpe&ing the formation of callus, alfo proves
the formation of new blood-veffels ; and the obfervations
of Mr John Hunter put this beyond a doubt. Till with¬
in thefe few years, it was thought impoffible that a di¬
vided nerve ihould re-unite; but fome late experiments
of Mr Cruikfhank have proved that this re-union may
take place*.
Under this head we may mention fome curious ex-
■ periments that have been lately made by Dr Jones, on
the means by which nature fupprefies the haemorrhage
from divided arteries. Thefe experiments were made
on dogs, and the refults of them lead us to con¬
clude, that the following is nearly the procefs by udiich
the haemorrhage is fuppreffed. Firft, the divided artery
contrafts, and is drawn within the neighbouring parts ;
blood is gradually effufed into the {heath of the artery
and the adjoining cellular fubflance, where it is entang¬
led, and affords a bafis for the formation of a coagulum or
clot, which furrounds the extremity of the divided ar-
tery, and prevents the farther effufion of blood, till ano¬
ther clot is formed within the mouth of the artery, plug¬
ging it completely up. Soon after there oozes out be¬
tween the external and internal clot, a quantity of co-
agulable lymph, which cements all the parts together,
and thus in time, if the artery divided be not very large,
and the force of the circulation very great, the cavity of
the veffel and the divided extremity, is obliterated, and
all further lofs of blood effe&ually prevented f.
It is, however, in the lower clalies that we are to look
for the moll remarkable inftances of this provifion of na¬
ture, particularly among the reptiles, cruftacea, moiiuf-
ca, worms, and polypes.
In many reptiles, the legs and tail, when cut off, are
foon renewed, and even the eyes have been re-produced.
Some interefting experiments on this fubjeft by Spallan¬
zani have been related under Erpetology, p. to
which v.Te refer the reader.
In the cruftacea, the legs and claws are very often
torn aw’ay, either by accident, or by fome voracious ani¬
mal •, but thefe never fail to be renewed in a Ihort time,
provided the animal is in good health. I his is moft re¬
markable in the craw-fifh (cancer aftacus, Lin.). ^ It
has been obferved that when the claw of this animal is
broken, the moft diftant part is gradually call off, and
about a day or twm after, a red membrane, not unlike
a bit of red cloth clofes up the aperture. This is at
firft plain *, but in the courfe of four or five days it af-
fumes a convexity, which gradually augments till it
takes the appearance of a fmall cone, which exceeds not
a line in height. It continues, however, to ftretch out,
and in ten days it is fometimes more than three lines, or
about one-fourth of an inch high. It is not hollow, but
2 '
O L O G Y. Chap XIV.
filled with flefh, and this flefti is the bafis or rudiment of Of Repro-
a new claw. The membrane that covers the flefh per- , *' ,
forms the fame office to the young claw as the mem¬
branes do to the foetus of the larger animals. It ex¬
tends in proportion as the animal grows ■, and as it is
pretty thick, we'can perceive nothing but a lengthened
cone. When 15 days are elapfed, this cone inclines to¬
wards the head of the animal. In a few days more its
curvature increafes, and it begins to affume tne appear¬
ance of a dead claw. This claw, though at the end of
a month or five weeks it has acquired the length of fix
or feven lines, wdrich is more than half an inch, is ftill
incapable of action. The membrane in which it is en-
clofed becoming gradually thinner, in proportion as it
extends, gives an opportunity of obferving the parts of
the claw, and we now perceive that this conical fub-
ftance is not a fimple congeries of flefh. Ihe moment
is now arrived when the claw7 begins to be brought
forth. The membrane at laft burfts, and the new clawr,
though ftill foft, appears without incumbrance or inveft-
ment. In a few days more it is covered wuth a fhell ;
and though ftill delicate, and not the half of its former
length, it is able to perform all the natural funftions.
It has likewife been difeovered, that, whether the claw
has been lopped off at the fourth articulation, or any- _ ^
where elfe, the animal in a fliort time recovers all that *
it had loft. The fame reproduction takes place alfo in ^^ol.
the horns; but, if the tail is cut oft, the animal furvives ij;.
a few7 days only *. . .. 3o8
Many of the mollufca exhibit curious inftances of re-in mollu.-
produftion, efpecially the aftinia, the Itar-fifh, andta’
fnails. The Abbe Dicquemaire made feveral experi¬
ments to afeertain the reproductive power of the aclinia
rufa (purple fea anemony). He firft cut off all its len-
tacula, which grew7 again in lefs than a month ; and on
repeating this a fecond and third time, he had equal
fuccefs. He cut off the upper part of one, and a few days
after, the bafe of the animal was found to have fallen
from its place; but it foon entirely recovered its limbs.
But if the bafe of thefe animals is injured by the inci-
fion, the wound commonly proves mortal, i he arms
of the ftar-filh are often torn off, but appear always to
be reproduced. The power of fnails in this refpeCl
is very great; for Spallanzani has afeertamed, that even
if their heads are cut off, thefe are regenerated in no
very long time. There can fcarcely be a more furpri-
fing inftance of animal reproduction than this, as we
fhall readily allow, if w7e confider the complicated
ftruCture of the head of a fnail *, that it contains a bram
divided into two parts ; that the horns attached to it
are furnifhed with mufcles, and that on the tops of the
larger horns there are eyes, compofed of two coats
and three humours; that the head contains a mouth,
lips, teeth, and a palate ; and yet all thefe parts, when
cut a wav, have been reproduced in the courfe 0! a few
weeks. 3°9
On the reproductive power of polypes we have been in polypes,
fufficiently minute under Helminthology, T\ 84. ^ 310
As this fubjeCt of partial reproduction is extremely 0*
curious, and as wt cannot here enter upon any particu- (ia<q;on 0f
lar detail on the experiments and obfervations that have parts,
been made on the fubjeCt, w7e {hall conclude this part
of the prefent chapter by enumerating the principal
works to which the reader may refer for a more fatif-
faCtory account of the fubjeCt. I hefe are chiefly 1 rem-
* bley,
Tpecies by
generation.
312
Organs.
313
Nature of
Chap. XIV. P H Y S I
Of Repro- bley, Menioires fur Its Polypes; Bonnet, Traite r/’ In-
, ducbon' feBologie, Palingenefe, and Conf derations fur les Corps
y" OrganfeSy vol. ii. •, Reaumur, fur les Inf Els; Spallan¬
zani, 7 raEls on Animals and Vegetablesy and Rjfay on
Reproduction; Hunter’s Treatife on the Bloody See. j
Ruffel’s Practical E/Jay on Necrofs Moore on the
Healing Procefs ; Murray, de Redintegratione Partium;
and the publications of Dr Jones and Mr Cruiklhank
already referred to. There is alfo a neat view of the
principal fads relating to this fubjed in a thefis De Vul-
nere Nature? Sandndoy publilhed at Edinburgh in 1805,
311 by Dr John Gordon.
^ionofthe ^ e ^ave a^reac^y ftated it as our opinion, that plants,
•fpecies by as we^ as animals» reproduce their like by generation.
We fhall not now enter on a difeuflion of the controver¬
ted point of the fexual fylfem ; and as the parts that
appear fubfervient to this fundion in plants, and their
various modes of propagation, have been fufficiently ex¬
plained under the articles Botany and PlaKt, we (hall
in this chapter confine our attention to the generation of
animals.
The human organs of generation are deferibed in the
article Anatomy, fed. xv. thofe of the cetacea under
Cetology, N° 161.J thofe of birds under Compara¬
tive Anatomy, 277 : thofe of filhes have been noticed
under Ichthyology. For a more full comparative
view of thefe organs, we refer to Cuvier and Blumen-
bach.
  The nature of generation which is the greatefl my-
generation. fiery in the economy of living bodies, is dill involved in
impenetrable obfeurity. The only circumftance com¬
mon to all generation, and confequently the only effen-
tial part of the procefs, is, that every living body is at¬
tached at firft to a larger body of the fame fpecies with
itfelf. It conftitutes a part of this larger body, and de¬
rives nourilhment, for a certain time, from its juices.
The fubfequent feparation conftitutes birthy and may
be the fimple refult of the life of the larger body, and
of the confequent developement of the fmaller, without
the addition of any occafional adion.
Thus the effence of generation confifts in the appear¬
ance of a fmall organized body in or upon fome part of
a larger one 5 from which it is feparated at a certain
. period, in order to affume an independent exiftence.
All the proceffes and organs, which co-operate in the
bufinefs of generation in certain claffes, are only accef-
314 fory to this primary fundion.
TJemmipa- When the fundion is thus reduced to the mod fimple
mion^" ^ate’ 11 conft^utes the gemmiparous, or generation by
flioots. In this way the buds of trees are developed into
branches, from which other trees may be formed. The
polypes (hydra) fee Helminthology, N® 84. and
the lea anemones (adiniae), multiply in this manner $
fome worms are propagated by a divifion of their body,
and mud, therefore, be arranged in the fame divifion.
This mode-of generation requires no didindion of fex,
no copulation, nor any particular organ.
Other modes of generation are accomplilhed in ap¬
propriate organs; the germs appear in a definite fitua-
tion in the body, and the adidance of certain operations
is required for their further developement. Thefe ope¬
rations conditute fecufidationy and fuppofe the exidence
oi fexual parts; which may either be feparate, or united
in the fame individual.
In mod animals the embryo of the future young- is
Vol. XVI. Part II. ^
315
Fecunda
■tion.
O L O G Y. 5? -$
fecundated within the peculiar organs of bne individd- Repro-
al, while another of the lame fpecies is provided with clu<d,0'!*
the means of giving adivity to the embryo by a fecun¬
dating duid. In fome animals, however, both thefe of¬
fices are performed by the fame individual, which is then
faid to be androgynous, or hermaphrodite. ^
The office of the male fex is that of furnilhing the Diftindliou
fecundating ox femmalfluid; but the manner in which of fexes;
that contributes to the developement of the germ is not
yet fettled by phyliologids. In feveral indances, par¬
ticularly in the frog, the germ may be clearly recogni¬
zed in the ovum before fecundation; its pre-exidence
may be inferred in other cafes from the manner irr
which it is conneded to the ovum when it fird becomes
vifible 'y for it is agreed on all hands, that the ovum
exifts in the female before fecundation, ftnee virgin hens
lay eggs, &c. . ^
The combination of the fexes and the mode of fecun- Herma-
dation are fubjed to great variety. In fome indances phroditeS*
they are united in the fame individual, and the animal
impregnates itfelf. The acephalous mollufca and the
echini exemplify this drudure. In others, although
the fexes are united in each individual, an ad of copu¬
lation is required, in wffiich they both fecundate, and are
fecundated j this is the cafe wdth the gaderopodous
mollufca and feveral Worms. In the remainder of
the animal kingdom the fexes belong to different in¬
dividuals. 5ig
The fecundating liquor is always applied upon or Modes of
about the germs. In many cafes the ova are extruded 1rnPrtgna-*
before they are touched by the lemen, as in fome bony fidies tK'h*
and the cephalopodous mollulca. Here, therefore, im¬
pregnation is efieded out of the body, as it is alfo in the
frog and toad. But in the latter inltances the male em¬
braces the female, and difeharges his femen in propor¬
tion as die voids the eggs. In mod animals the leminal
liquor is introduced into the body of the female, and
the ova are fecundated before they are difeharged.
This is the cafe in the mammalia, birds, mod reptiles,
and fome fidies; in the hermaphrodite gaderopodous
mollufca, in the crudacea, and iniedfs. In all the lad
mentioned orders ova may be difeharged wnthout pre¬
vious copulation, as in the preceding. But they re¬
ceive no further developement $ nor can they be fecun¬
dated when voided *. We diall not gratify the pruri-*Czm’irr
ent imagination of the philofophic feniualid, by any de- Lemons
tails of the mode in which thefe operations are carried
on in the various claffes of animals, except in one in-Vi0p^*j0rC*
dance, which is fo curious that we diall be excufed
for deferibing it. We allude to bhe copulation of the
■fnail.
Thefe animals meet in pairs, and dationmg them-Copulation
felves an inch or two apart, launch feveral little darts, of fnails,
not quite half an inch long, at each other. Thefe are
of a horny fubdance, and lharply pointed at one end.
The animals, during the breeding feafon, are provided
with a little refervoir for them, fituated within the
neck, and opening on the right fide. On the dif-
charge of the fird dart, the wounded fnail immediately
retaliates on its aggreffof by ejefting at it a fimilar dart;
the other again renews the battle, and in turn is again
wounded. Thus are the darts of Cupid, metaphorical
with all the red of the creation, completely realifed
in fnails. After the combat they come together*. Each
of them lays its eggs in fome flickered and mold fitu-
3 T • tioiq
5H
Of Repro-
duflion.
f Shaw's
JVatura-
lift's Mif-
ccllany,
vol. i.
320
321
Oviparous
generation.
PHYSIOLOGY.
323
Ovo-vivipa
rous ani¬
mals.
3l3
Viviparous
generation.
* Cuvier t
ICC.
fion, generally under a little clod of earth, or in fome
cool cavity f.
The efteft of a {ingle copulation varies in its degree :
it ufually fecundates one generation only ; but iome-
times, as in poultry, feveral eggs are fecundated} Hill,
however, they only form one generation. In a very
few inftances one aft of copulation fecundates feveral ge¬
nerations, which can propagate their fpecies without
the aid of the male. In the plant-loufe (aphis) this has
been repeated eight times; and in fome monocuh x 2 or
15 times.
When the germ is detached from the ovary, its mode
of exiftence may be more or lefs complete. In moll
animals it is connebled, by means of vefiels, to an orga¬
nized mafs, and the abforption of which nourifhes and
dpvelopes it until the period of its birth. It derives
nothing, therefore, from the body of the mother, from
W'hich it is feparated by coverings varying in number
and folidity. The germ, together with its mafs of nou-
rithment, and the furrounding membranes, conftitutes
an egg, or ovum ; and the animals which produce their
young in this date, are denominated oviparous.
In mod of thefe the germ contained in the egg is not
developed until that part has quitted the body of the
mother, or has been laid; w'hether it be necellary that
it diould be afterwards fecundated, as in many fidies •,
or require only the application of artificial heat for its
incubation, as in birds j or that the natural heat of the
climate is fufficient, as in reptiles, infetds, &c. Thefe
are dridlly oviparous animals.
The ovum, after being fecundated and detached from
the ovarium, remains in fome animals wfithin the body
of the mother* until the contained germ be developed
and hatched. Thefe are falfe viviparous animals, or
ovo-viviparous. The viper, and tome tidies, afford in¬
dances of this procefs. Mammalia alone are truly vivi¬
parous animals. Their germ poflefles no provifion of
nourilhment, but grows by vrhat it derives from the
juices of the mother. For this purpofe it is attached to
the internal furface of the uterus, and fometimes, by ac¬
cident, to other parts, by a kind of root, or infinite ra¬
mification of veflels, called placenta. It is not, there¬
fore, completely feparated from the mother by its co¬
verings. It does not come into the wTorld until it can
enjoy an independent organic exiftence. The mamma¬
lia cannot, therefore, be faid to poffefs an ovum in the
fenfe which we have afligned to that term.
From this view of the fubjefl, generation may be faid
to confift of four functions, differing in their importance,
and in the number of animals to which they belong.
1. The produBion of the germ, which is a conftant
circumdance •, 2. Fecundation, which belongs only to
the fexual generation 5 3. Copulation, which is confined
to fchofe fexual generations, in which fecundation is ac-
complifhed within the body; 4. Uterogejlation, which be¬
longs exclufively to viviparous generation *.
There is a general rule obfervable among all quadru¬
peds, that thofe which are large and formidable pro-
Chap. XIV.
duce but few at a time } while fuch as are mean and Of Repro-
contemptible are extremely prolific. The lion, or tiger,
have feldom above two cubs at a litter *, while the cat, ~
that is of a fimilar nature, is ulually feen to have five or Compara-
fix. In this manner, the lower tribes become extreme- live fecun-
ly numerous 5 and, but for this fuipriling fecundity, dhy ot ar>i-
from their natural weaknefs, they w7ould quickly be ex-mais#
tirpated. The breed of mice, for indance, would have
long fince been blotted from the earth, w'ere the moufe
as ilow in production as the elephant. Eut it has been
wifely provided, that fuch animals as can make but lit¬
tle refiitance, fliould have at lead a means of repairing
the dedruftion which they mud often differ, by their
quick reproduction ; that they (hould increafe even
among enemies, and multiply under the hand of the de-
droyer. On the other hand, it has as wifely been or¬
dered by Providence, that the larger kinds {hould pro¬
duce but llowly ; otherwife, as they require proportion¬
al lupplies from nature, they would quickly confume
their own dore •, and, of confequence, many of them
would foon perilh through wTant j fo that life would thus
be given without the neceflary means of fublidence. In
a word, Providence has mod wifely balanced the drength
of the great againlt the weaknefs of the little. Since it
was neceflary that fome drould be great and others
mean, fince it w7as expedient that fome Ihould live upon
- others, it has addled the w'eaknefs of one by granting it
fruitfulnefs, and diminidied the number of the other by
infecundity.
In confequence of this provifion, the larger creatures,
wdich bring forth few at a time, feldom begin to gene¬
rate till they have nearly acquired their full growth.
On the contrary, thole wThich bring many reproduce
before they have arrived at half their natural fize. Thus
the horfe and the bull are at their bell before they begin
to breed : the hog and the rabbit fearce leave the teat
before they become parents in turn. Almod all animals
likewife continue the time of their pregnancy in propor¬
tion to their fize (l).
For an account of the principal phenomena attending
the reproduction of the human fpecies, viz. the requi-
fites for conception and its figns ; the effeCts of impreg¬
nation ; the gradual evolution of the foetus, and the
fuccedive changes that take place in the uterine fydem
during uterogedation, fee the article Midwifery,
chap. i. and ii. The phenomena of reproduction in other
viviparous animals are fo analogous to thofe in the hu¬
man fpecies, that we need not enter on an examination
of them. We {hall here only give a view of the fuccef-
five changes that take place in the egg of birds during
incubation, taken from the obfervations of the celebrated
Blumenbach.
The following obfervations refer to the egg of the
common hen, as affording the mod familiar example ofp1ro£rcffiv®
, . 7 0 changes of
incubation.
A fmall {hining fpot, of an elongated form, with during ^
rounded extremities, but narrowed in the middle, iscubation.
perceived at the end of the fird day, not in nor upon
the
3*5
326
(l) In the following table are noted the time of geftation, incubation, and the number of young produced in fe¬
veral fpecies of quadrupeds and birds, as far as thefe have been afcertained 5 and the fecond column {hews the
period to which the life of each is ufually extended.
Chap. XIV.
Of Repro- the cicatricula (m), but very near that part on the yolk-
, (Inchon, This may be faid to appear before-hand, as the
, *7 abode of the chick which is to follow.
Secojid No trace of the ‘Jitter can be difcovered before the
cuy.
PHYSIOLOGY. ' 5,5
beginning of the fecond day and then it has an incur- Of Repro.
vated form, refembling a gelatinous filament with large du(^lon-
extremities, very clofely furrounded by the amnion,
which at firft can fcarcely be diftinguiflied from it.
3 T 2 About
Species.
n
w
CL,
«!
<!
oi
Apes.
Bats.
Sloth.
Rhinoceros.
Elephant.
Arctic walrus.
Seal.
Bitch.
Wolf.
Fox.
Jackall.
Lionefs.
Tigrefs.
Cat.
Ferret.
Otter.
Virginian opoffum.
< Kanguroo.
Mole.
Porcupine.
Guinea pig.
Common rat.
Moufe.
Common fquirrel.
Hare.
Rabbit.
Camel.
Rein deer.
Stag.
Goat.
Ewe.
Cow.
Mare.
„ Sow.
f Eagle.
Raven.
Cuckoo.
Humming bird.
Blackbird.
Canary bird.
Wren.
Pigeon.
Turkey.
Hen.
Oftrich.
Swan.
Goofe.
Duck.
Period of Life.
70 or 80 years.
Above 100 years.
12 or 16 years.
About 14 years.
Above 70 years.
From 10 to 18 years,
6 or 7 years.
From 2 to 3 years.
40 or 50 years.
15 or 16 years.
Near 50 years.
15 years.
30 or 40 years.
Nearly 20 years.
Above 100 years.
Near 100 ditto.
10 or 20 years.
About 13 years.
Above 100 years.
Near 100 years.
Time of Geftation.
21 months.
9 months.
9 weeks.
3x months.
6 weeks.
8 weeks.
6 weeks.
9 weeks.
3 weeks.
5 or 6 weeks.
6 weeks.
A month.
Ditto.
12 months.
8 months.
5 months.
5 months.
Ditto.
9 months.
11 months.
4 ditto.
l ime ot Incubatit
30 days.
20 ditto.
12 days.
14 ditto.
Ditto.
Ditto.
Ditto.
A month.
3 weeks.
Six weeks.
Ditto.
A month.
Ditto.
Number of Young.
About 2.
From 2 to c.
One.
One.
One.
One.
About two.
From 4 to 10.
5 or 6.
From 3 to 6.
From 6 to 8.
4 ?r 5-
Ditto.
From 4 to 6.
6 or 7.
4 or 5.
Ditto.
One.
4 or 5.
Two.
From 5 to 12.
From 12 to 18.
From 6 to 10.
From 4 to 5.
3 or 4-
About 8.
One.
Two.
One.
About 2 or 3.
From 1 to 2.
1 to 3.
1 or 2.
From 10 to 20.
2 or 3.
5 or 6.
1 or 2.
Two.
4 or 5.
Ditto.
From 10 to 18.
Two.
18 or 20.
About 20.
One or two each.
6 or 8.
9 to 12.
12 to 14.
„f Tl“ of a? has alr,ea<iy b«" defcribed under the article Egg ; but for the better underftandi™
by *7au,h„Ch S ?rb rVatT’ 11 T? bc,nec/5irary 10 'numerate the feveral parts, with the names given to them
ejL • r‘ r i Ke J^mbrane lining the fhell is called membrana albumims, and includes the two whites of the
n t.I1Iler v U KI: I Surrounds the yolk, which is contained within a peculiar, very delicate membrane called
the From two oppoflte fides of this bag proceeds a white knotty body, terndnating in dTe whTte of ^
^’,7 a ?°f k ent extrem“y- Th'f' bodies are called the rAttW orgrlnJml; the ctcu/rL/u, Vread or toddle
bounded by one or more whitilh concentric circles called uLs, or brc/i, the ufe’5 which is
5i 6
.Of Repro¬
duction.
PHYSIOLOGY.
About , this tims ‘the- hijloncs enlarge their circles aud the chorion, winch are .-o
but they.foon after difappear entirely, as well as the ci-
Chap. XIV:
328
Third day.
catncula.
The firil appenrauce of red blood is difcemed' on the
fiirface. of the yolk-bag, towards the end of the fecond
day. A feries of points is obferved, which form grooves j
and thefe doling, conilitute veifels, the. trunks of which
become connected to • the chick. The vafcular furface
itlelf is called Jigura ventfci, or area v'afculofaand the
veffel by which its margin is defined," vena termmalii.
The trunk of all the veins joins the vena pertce ; while
the arteries, which ramify on the yolk-bag, arife from
the mefenteric artery of the chick.
On the commencement of the third day; the newly
formed heart is difcerned by means of its triple pulfa-
tion, and conftitutes a threefold punSium/aliens. Some
parts of the incubated chicken are deftined to undergo
fucctiTive alterations in their form 5 and this holds good
of the heart in particular. In its firft' formation it re-
fembles a tortuous canal, and confifts of three dilations
lying clofe together,.and arranged in a triangle. One
of thefe, which is properly the right, is then the com¬
mon auricle ; the other is the only ventricle, but after¬
wards the left; and the third is the dilated part of the
aorta.
About the fame time, the fpine, which was originally
extended in a ftraight line, becomes incufvatedj and
the diftinffion of the vertebrae is very plain." The eyes
may be diftinguifhed by their black pigment, and com¬
paratively immenfe fize •, and they are afterwards re¬
markable in confequence of a peculiar flit in the lower
329. part of the iris.
Feurth day. From the fourth day, when the chicken has attained
the length of four lines, and its moft important abdomi¬
nal vifcera, as the ftomach, inteftines, and'liver, are vi-
fible, (the gall-bladder, however, does not appear till
the fixth day), a vafcular membrane begins to form
about the navel; and increafes in the following days
with fuch rapidity, that it covers nearly the whole inner
furface of the fhell, within the membrana albuminis, du¬
ring the latter half of incubation. This feems to fupply
the place of the lungs, and to carry on the refpiratory
procefs inftead of thofe organs. The lungs themfelves
begin indeed to be formed on the fifth day ; but, as in
the foetus of the mammalia, they muft be quite incapa¬
ble of performing their functions while the chick is con¬
tained in the amnion.
Voluntary motion is firft obferved on the -fixth day,
when the chick is about feven lines in length.
Offification commences on the ninth day, when the
olTific juice is firft fecreted; and hardened into bony
points. Thefe form the rudiments of the bony ring of
the fclerotica, which refembles at that time a circular
row of the moft delicate pearls.
At the fame period, the marks of the elegant yellow
veffels on the yolk-bag, begin to be vifible. •
On the fourteenth day the feathers appear ; and the
animal is abk to open its mouth for air, if taken out of
the egg;
Qn the xuneteenth day it is able to utter founds ^ and:
omthe twenty-fir ft to break through its prifon, andcom^
naence amevrdtfei
Blamenbach concludes his obfervations < with a few
remarks on tboihvery. fingular membranes; the yolkthag.-
336
Sixth day.
33i
Plinth day.
33*
Fourteenth
day.
. 333
Nineteenth
day.
eflhtitiai to tko life and ®i'-Repra«
ptrefervation of the animal. , duction. ^
The chorion, that-moft firaple yet moft perfect tem- ' ' 1'
porary fubftitnte for the lungs,, if examined in the kt-Remains
ter half of incubation in an egg very cautioully opened, on the cho*
prefents, without any artificial inje&ion, one of the moft n0B*
1’pkndid fpeftacles that occurs in the whole organic cre¬
ation. It exhibits a furface covered with, numberlefs
ramifications of arterial and venous veffels. The latter
are of a bright fcarlet colour, as they are carrying oxy¬
genated blood to the chick; the arteries, on the con¬
trary, are of a deep or livid red, and bring the carbonat¬
ed blood from the body of the animal. Their trunks
are corine&ed with the iliac veffels •, and, on account of
the thinnefs of their coats, they afford the beft micro-
fcopical object for demonftrating the circulation in a
warm-blooded animal.
The other membrane is alfo conne&ed to the body On the yolk
of the chick j but by a two-fold union, and in a very bag.
different manner from the former. It is joined to the
fmall ifiteftine, by means of the duElus vitello-intejiina-
//>, and alfo by the blood-veffels,* with the mefenteric
artery and vena portse.
In the courfe of the incubatipn the yolk becomes con-
ftantly thinner and paler, by the admixture of the inner
white. At the fame time innumerable fringe-like vef¬
fels with flocculent extremities, of a moft Angular ftruc-
fure, form on the inner furface of the yolk-bag, oppo-
fite to the yellow ramified marks, and hang into the
yolk. There can be no doubt that they have the office
of abforbing the yolk, and. conveying it into the veins
of the yolk-bag, where it is affimilated to the blood, and
applied to the nutrition of the chick. Thus in the chick
which has juft quitted the egg, there is only a remain¬
der of the yolk and its bag to be difcovered in the abdo¬
men. Thefe are completely removed in the following
rveeks, that the only remaining trace is a. kind of ci¬
catrix on the furface of the inteftine * Blum^a.
Many of the caufes which contribute to the forma- h/ch's
don of a living body have hitherto eluded human re-
fearch ; may in all probability never be difcovered ; and KKVij.’
perhaps are beyond human comprehenfion. ... 33?
Some philofopkers, difcovering the extreme divifibili- Theories of
ty of matter, and learning from the microfcop that gcnerat1011*
transformation is but the developement of certain parts 337
that previoufly ejdfted, have thence imagined that ge-^P^?^
neration is fomewhat analogous5 that all organifed bo- eY0]uti0IU
dies received their form at the beginning ; that the firft
of every genus and fpecies contained by involution the
mimberlefs millions offucceeding generations j and that
the union of the two fexes gives only a ftimulus, and
brings into view forms that had exifted fince the world
began* # 338
By this hypothefis they have attempted to explain a objectkliS
thing that is unknown by what muft remain for ever in-
comprehenlible to the human mind in its prefent ftate.
They afefurdly appeal from obfervation to conje&ure; and
fuppofe that bodies which are originally brought into
view, which are daily, augmented, frequently repaired,
and fomfctimes renewed by organic a&ion, do neverthe-
lefs in their firft formation require an effort fuperior to
wbat omnipotence is; able to perform by fecondary
agents. Had the fupporters of this hypothef • confider-
ed- that many herbaceous plants produce, new flowers
when
Chap, Xtv: P H Y s I'
Of K;epro- when the fitft fet are untimely cut off 5 that lobfters andi
d*lt^IQn- many other animals renew their limbs, and that certain
v ' polypes can raife a ftrufture fo perfe&ly refembling a
vegetable form as to puzzle the naturalift whether or
not he Ihould clafs them under plants, they would fure-
ly not have prefcribed fuch bounds to ommfcient wif-
dom and almighty power, or declared with fuch confi¬
dence what the Author of nature, to fpeak with the vul¬
gar, mult neceffarily perform by his own hands, or
what he may intruft to fecondary caufes regulated by his
laws.
Thefe philofophers wall find it difficult to account in
a very fatisfadlory manner for monitrous productions,
and for thofe changes of ItruCture and of form which for
a while continue hereditary from the influence of habit.
They objeCt to others, that all the parts of a living
body arc mutually dependent on one another, and that
they mult neceffarily have been coeval, or have cxilted
at once. But though every attempt that has yet been
made to afcertain which of the vital organs are prior
and which polterior in a living body has proved unfuc-
cefsful, it ffias not been demonlirated that either them-
felves or their functions are coeval. It may, on the
contrary, be plainly demonltrated from obfervation,
that the lungs and the Itomach do not begin to perform
their functions fo early as the heart and the vafcular
fyltem 5 that even the heart and its fyltem perform their
fimClions with fome confiderable changes, immediately
after birth; that the vegetable tribes are without nerves j
and that the brain and nerves in the animal king¬
dom perform more and more of their functions, accord¬
ing as the fyltem approaches towards maturity. It has
even been Ihewn* that bones will unite j that the limbs
of an animal continue to be nourilhed without the
nerves; that there is a principle of life in the blood;
that the heart will aCi under other Itimuli befide that
of nervous influence ; and found logic does by no means
require us to fuppofe* that the firft aCtion of the foetal
heart, or the pun&um /aliens, is owing to the influ¬
ence of ftimuli from the brain, or that the brain muft
have exilted when the heart firll moved. Although the
minutenefs and tranfparency of the parts may prevent
us from feeing the firll gradual formation of the embryo,
yet every obfervation corroborates the opinion, that it
is formed by fecondary caufes, and through the medium
of organic powers.
Molt phyfiologiits have- believed, the certain inorga¬
nic particles are contained in the fyllem of one fex or of
the other, and that by the union of the fexes thefe par¬
ticles have become organifed. It has* however* been
alked whether or not is the- embryo formed by the joint
operation of the two fexes ? or is it formed entirely by
one, and brought into aClion by a flimulus from the
other •? The former of'thefe queitions fuppofes that each
of the fexes has afeminal fluid; that fome mixture takes
place in the uterus, and produces an embryo, in the
lame manner that a neutral fait affumes a certain and de¬
terminate form. The notion implies fome general and
confufed ideas of chemical combination ; but does not
befpeak a very clear underltanding, profound reflec¬
tion, or much acquaintance with the nature and pro¬
perties of living bodies.
For a long time pall the moll rational phyfiologills
have generally thought that the embryo is formed gra-
339
Hypothefis
of Eplge-
cefis.
O L O G Y.
dually and flowly in one or other of the two fexes, rfofc OfRepro-
by chemical combination, but a fyflem of-organs, di- dL,(^ion*
reeled by laws and prompted by llimuli, with many of
which we are yet unacquainted. From the great Hip¬
pocrates to Fabricius and Harvey, the-credit of furniffi-
ing the foetal embryo wras almoil univerfaliy given to
the females of oviparous animals. Among the viviparous,
appearances were fuch, that the female was left to con-
tell it with the male. At lail the eclat of Leeuwen-^ ^
hoek’s difeoveries feemed to put an end to all doubts en- fuppofed to
tertained upon the fubjeft. He very plainly faw through be derived
his microfcope that very great profufion of particles thatfrofT1 ’-he-
move to and fro wfith amazing rapidity in the male
men. Upon this he embraced the doblrine of Hamme,
who had feen them before, and fuppofed from their mo¬
tions that thefe particles were not only animalcules, but
the principles or rudiments of that animal in whom they
were formed, and that they were depofited in the ute¬
rus of the female only to be nourilhed and augmented in
fize.
What raifed obje&ions againft this theory was, that Objection;;
numerous animalcules were difcoverable by the micro¬
fcope in othei fluids, and that a vaft profufion of young
embryos appeared in cafes where never more than one or
two arrive at-maturity. It w^as an objection to it, that
fome females had been impregnated, where the hymen
remained unbroken, lo that the impregnating fluid could
have reached only the mouth of the uterus. Again,
m frogs, fiffies, and many other animals, the ova are
not impregnated till after extrufion ; and laftly, Haller
had obferved the chick completely formed in eggs that
had not been fecundated.
It is now,. wre believe, pretty generally known, that
the embryo does not commence its exiftence in the ca¬
vity of the uterus. De Graaf obferved it on its paffage
down the fallopian tube ; he faw the place where if fir A:
began in the ovarium of the female, and cafes have oc¬
curred where it has miffed the fallopian tube, where it
has fallen into the abdomen, in which the placenta has
been formed, and the foetus has grown among the
bowels. 6
. From thefe fafls it has been concluded, notwithftand- Mor^pro-
ing fome feeble obje&ions, that the female ovaria con-bable that
tain the embryos in the form of eggs ; that thefe eggsthe en?brv''
are brought into aftion by the ftimulating power of the female" ^
male femen, which is fometimes thrown into the cavity
of the uterus,, fometimes applied only to its mouth, and
fometimes fprinkled on the eggs after they are extruded.
For more on this fubjedl fee the article Midwifery. 34-
A view of the relations between the prefent fun&ion Relanonv
and thofe which we have before examined, is a fubje&
of fo delicate a nature, that we muff not enlarge on it.
The fympathy between the reprodu&ive and the ner¬
vous fyfiems is well known. The effeft which defir«
has occafionally produced on the brain is very great
madnefs being not unfreqyently the confequence, either
of too much indulgence, or of total continence. We
are.of opinion that tlie influence of the fancy or imagi¬
nation on the uterine fyftem has been over-rated, though
the accounts given of monllers or deformed births, in •
confequence of terror experienced by the mother, ’ap¬
pear to be too. well authenticated to warrant our total
diffielief in this influence. Too much indulgence in
this appetite produces a debilitated ftate, both of
the
5i8
PHYSIOLOGY.
Of Sle?p the mental and bodily functions, and deprives the fyf-
ancl Torpor. tem Qf natural ftimulus which feems eflential to the
activity and vigour of the body in the male.
Chap. XV. Of Sleep and Torpor.
NecSnty of We have already confidered the aftive means by
deep. which the wafte of the body is repaired \ but all thele
would have little effe£t, and could not indeed be carried
on for any confiderable time, without fome general re*
laxation of the fyftem. This relaxation is brought
about by deep, in which the a&ive fun&ions find a re¬
pole from the labours which they have undergone during
the day; and in this way the fyftem is recruited more
345 completely than by any other means.
Sleep, an Sleep may be confidered as awafteftion of mind, and
affection of therefore more properly a fubjeft of metaphyfical, than
mind’ of phyfiological fpeculation. It is, however, generally
treated of in fyftems of phyfiology •, and it will be ne-
ceflary to take notice of fome circumftances refpefting
it. We fhall chiefty confider the ftate of the body and
mind during deep, and fome of the principal theories
g that have been contrived to account for it.
Phenomena Natural deep returns at certain intervals, which, are,
of fleep. however, difterent in different animals. Moft animaiS,
and efpecially man, deep only during the night, but
moft of the predacious fpecies, as beafts and birds of
prey, choofe this time for their predatory excurfions,
and repofe during the day. Sleep comes on with an un-
ufual languor and laflitude ; an averfion t© motion ; the
mind becomes unfit for its ufual exertions; and the de-
fire of reft pervades the whole fyftem. In particular,
the extenfor mufcles lofe their power of preferying the
body in an ere& pofture ; the eyelids involuntarily fall;
the head bows forward; the joints bend, and the body
finks. During deep, all the voluntary motions are in
general fufpended j but the involuntary actions of the
heart and lungs proceed, though not fo vigoroudy as in
the waking ftate *, the circulation and refpiration being
dower than ufual. Moft of the fenfes are alfo in a ftate
of repofe, efpecially thofe of feeling,. fmell, and pro¬
bably of tafte. Hearing is, in fome animals, very acute
during deep, and they are thus enabled to efcape any
danger that threatens them. Some animals, as the hare,
alfo deep with their eyes open ; and in moft the impref-
fion of light, when the eyelids are raifed, h very evi¬
dent. The funftions of digeftion, abforption, and fe-
cretion, feem to proceed with greater eafe and a&ivity
during deep} and adimilation and nutrition are much
promoted by this ftate of repofe. Some of the faculties
of the mind, efpecially the imagination, are, however,
in full vigour, as appears from the dreams that take
■place during deep. The duration of deep is exceeding¬
ly various. Among the human fpecies, young chil¬
dren, and very old perfons, pafs the greateft half of
their time in deep, while middle-aged and aftive people
feldom deep fo much as one third of the 24 hours. -
Though the returns of deeping and waking depend
much on cuftom, they may, however, be changed by
various circumftances j and though the commencement
of one of thefe periods happen to be altered, that of the
other may remain as before. If a perfon is accuftomed
to go to deep exaftly at nine in the evening, and to rife
again at fix in the morning, though the time of deep
may be occafionally protra&ed till twelve, he will yet
2
Chap. XV.
aivaken at his ufual hour of fix: or if his deep be conti- Of Sleep
nued by darknefs, quietnefs, or fimilar caufes, till thean(l torpor.
day be farther advanced, the defire of deep will return v
in the evening at nine. 347
- Moft of the caufes that produce or prevent deep, have Theory of
been mentioned in the article Medicine, N° 94. As^eeP'
to the immediate caufe, the opinions of phyfiologifts are
much at variance, and the theory of deep is as little un-
devftood as that of any funftion of the animal eco¬
nomy. 348
According to Haller, deep arifes, either from a fim- Hypothcfis
pie abfence, deficiency and immobility of the fpirits, orof ilalAer'
from compredion of the nerves, and always from the
motion of the fpirits through the brain being impeded *. * Yirfi
That deep is, fome how or other, connected with a com-
preflion of the brain, appears very probable, from the ^5.
heavinefs and coma that take place in cafes where fuch
a compredion has evidently been produced ; but how
this compreflion afts has never yet been fatisfaftorily ex¬
plained ; and the obftruftion that Haller fuppofes in
the motion of the animal fpirits, or nervous duid, is gra¬
tuitous.
One of the fadiionable do&rines of the prefent day Qf Brown,
refpetting the immediate caufe of deep is, that this ftate
is produced by an exhauftion of irritability or excitabili¬
ty. According to Brown, deep fucceeds a diminution
of excitement, during wdiich the excitability is either
only fo far diminiftied that it can be accumulated again,
or fo abundant, that the excefs can be wafted, and in
each cafe the excitement reftored f. ^ JLlem
Similar to this is the doftrine of Zoonomia, that deep 4^/ '
depends on an exhauftion of fenforial poiver. Dr Dar- §.'.337.
wan thus charafterizes perfedt deep: 1. The power of 330
volition is totally fufpended. 2. The trains of ideas Of Darwia.
caufed by fenfation proceed with greater facility and
vivacity •, but become inconfiftent wdth the ufual order
of nature. The mufcular motions caufed by fenfation
continue ; as thofe concerned in our evacuations during
infancy, and afterwards in digeftion, and in priapifmus.
3. The irritative mufcular motions continue, as thofe
concerned in the circulation, in fecretion, and refpira¬
tion. But the irritative fenfual motions, or ideas, are
not excited ; as the immediate organs of fenfe are not
ftimulated into adlion by external objedls, which are
excluded by the external organs of fenfe j which are not
in deep adapted to their reception by the power of vo¬
lition, as in our waking hours. 4. The affociate mo¬
tions continue, but their firft link is not excited into ac¬
tion by volition, or by external ftimuli. In all refpefts,
except thofe above mentioned, the three laft fenforial
powers are fomewhat increafed in energy during the fuf-
penfion of volition, owing to the confequent accumula¬
tion of the fpirit of animation j]. f Darwin's
Thus, the immediate caufe of deep confifts in the fuf-Zoo?zo/rcf«,
penfion of volition produced by the exhauftion of fenfo-xol. i. $. i«.
rial power •, and hence, whatever diminidies the gene¬
ral quantity of fenforial power, a£ls as a remote caufe of
deep.
Befide the infufficiency of thefe hypothefes to account
for many circumftances that take place during deep, we
may remark, that this ftate is often produced when no
exhauftion of irritability, excitability, or fenforial power,
can be fuppofed to have taken place. Thus, the pro-
penfity to deep often becomes irrefiftible from the effefts
of monotonous fpeaking, from ftilinefs, darknefs, or
from
Chap. XV. PHYSIOLOGY.
Of Sleep from the famenefs of the fceHerv around us j and when
and Torpor. one ftimulus, after long application, can arroufe no
_v more, another ftimulus that in ordinary cafes is lefs
powerful, produces excitement, and keeps off fleepj an
evident proof that excitability or fenforial power have
not been very far exhaufted.
Suppofed Plants have been faid to deep. At the approach of
fleep of night, many of them are obferved to change their ap-
plants. pearances very confiderably, and fometimes even to fuch
a degree as fcarcely to be known for what they are.
Thefe changes happen principally to the leaves and the
flowers. During the night, many leaves, according to
the nature and genus of the plant, are feen to rife up,
to hang down, or to fold themfelves in various ways,
for the prote&ion of the flowers, the buds, the fruits,
the young Items} and many flowers, to efcape a fupera-
bundance of moifture, to hang down their mouths to¬
wards the earth, or to wrap themfelves up in their ca-
lices. Thefe phenomena are owing to ftimuli a fling"
from without } we may add, that molt of the motions
are performed at the joints where the leaves and petals
articulate with the Item. A period of reft is as necef-
fary to plants as fleep is to animals. The irritable prin¬
ciple cannot aft long under the influence of the fame
ftimulus, except at intervals, and the rapid growth ob-
fervable in plants during the night, is a ftrong proof
that the organs employed in aflimilation had been dif-
turbed in difcharging their funftions during the day,
when expofed to the aftion of heat and light and of other
ftimuli.
Dreaming. 1° our general outline, we had propofed introducing
here an account of the phenomena of dreams, but we
find that this fubjeft has been fo fully difcuffed under
the article Dream, that any additional remarks would
be unneceffary. To this article therefore we refer the
reader.
Rules for the management of the body with refpeft to
fleep, fcarcely come within our prefent province 5 but as
wre pafs fo much of our time in this flate, during which
we are fometimes occupied in a very agreeable manner,
while at others we are fubjeft to moft uneafy fenfations,
it is a matter of confiderable confequence to take thofe
meafures which may fecure to us the former, and enable
us to avoid the latter. We have feen few rules better
adapted to thofe purpofes than thofe of Dr Franklin $
but as more important matter preffes for infertion within
the circumfcribed limits to which we are reftrifted, we
muft refer our readers to the original paper, wdiich is
publilhed in the late 8vo edition of Franklin's Works,
vol. iii. p. 437.
S imnarabu- a ^ew ca^es) not only the imagination has a full
lifm. range during fleep, but the voluntary motions of the
body, and even the exercife of feme of the external
fenfes, are carried on with apparently .as much perfec¬
tion as when the perfon is awake. This ftate is called
fomnambulifyn, or fleep-walking, and is commonly con-
fidered as a variety of dreaming. Many furprifmg ac¬
counts have been given of fleep-walkers. They have
been known to rife, drefs themfelves, go out of doors,
and fometimes out of a window, from which they have
climbed upon the roof of a houfe, dig in a garden, draw
water from a well, faddle a horfe and ride feveral miles $
maintain a rational and interefting converfation, and even
go through a laborious and difficult literary talk} and af¬
ter having performed thefe exploits, they have returned Of Sleep
to their bed without being confcious of what they had anci ToiTor-
been doing. This want of confcioufnefs appears from '
their remembering nothing when they awake, of what
pafied during their fleep. It is difputed whether fom-
nambuliits incur as much danger in the aftions which
they perform, as thofe who are awake, in fimilar cir-
cumftances. We are inclined to think that the danger
is much lefs in the former cafe, as fleep-walkers feem en¬
tirely free from the terror which commonly attends the at¬
tempting of any hazardous enterprife when aw ake; fuch as
mounting to the roof of a houfe, climbing a fteeple, &c.
If fuddenly awaked, however, while engaged in any of
their hazardous actions, the danger is very great.
Dr Darwin confiders fomnambulifm, not as a ftate of Reverie,
fleep or dreaming, but as a variety of reverie, carried to
a morbid extent, fo as to become a fort of epileptic or ca¬
taleptic paroxyfm. In the ftate of reverie, according to
Dr Darwin, the irritative motions occafioned by internal
ftimuli continue, thofe from the ftimuli of external ob¬
jects are either not produced at all, or are never fucceed-
ed by fenfation or attention, unlefs they are at the fame
time excited by volition ; the fenfitive motions continue,
and are kept confiftent by the power of volition 5 the vo¬
luntary and affociate motions continue undifturbed. He *
confiders reverie as an effort of the mind to relieve fome ' 1‘
painful fenfation, w hence it is allied to convulfion and *
infanity *. . 355
The torpor that takes place in many animals during TorPor
winter, appears to be fo nearly allied to fleep, that weanimiUS*
{hall confider it in this chapter.
A great variety of animals of almoft every clafs, re¬
tire during the cold of winter, to the receffes of ca¬
verns, holes in old walls, hollow trees, or below the
earth, where they remain in apparently a lifelefs ftate
till the return of fpring roufes them from their trance.
We fhall here enumerate the different animals that have
been known to undergo this ftate of hibernation.
- Bats, efpecially the vefpertilio murinus, auritus, and Hibernat-
v.noBula (fee Mammalia, N° 39) ; efpecially ing mam-
the brown and the polar bear, and the badger; the hedge- malia.
hog, Cerinaceus Europeus) ; feveral fpecies of the moufe
and rat tribe, but more efpecially the hamjier (mus cri-
cetus'), the marmots, efpecially the ar&omys marmota,
(fee Mammalia, N° i 24); the dor moufe (" myoxus mu/car-
dinus.) Sheep appear capable of living for a confiderable
time in a torpid ftate, as they have been known to re¬
main alive for feveral weeks, buried under the fnow.
It does not appear that birds in general are capable of Hibernation
undergoing this ftate of exiftence ■, but the inftances of of bird*;
fwallow's that have been found in this ftate in old walls
and hollow trees, and even, as fome affirm, below water,
and have recovered life and activity on being expofed to
gradual warmth, are too well authenticated to admit >a
doubt, that thefe at leaft fometimes hibernate. 358
Moft reptiles and ferpents pafs the winter in a ftate of of reptiles
hibernation ; but this is more particularly the cafe with and fer"
the land tortoife (tejludo greeca), fee Erpetology, pents ’
p. 271 $ frogs, and thofe lizards which inhabit cold cli-
mates. _ 359
It is not certainly known whether many fpecies of filh of fifties;
become torpid in winter ; but there is no doubt that fe-
veral of them are fufceptible of this ftate * ; and we are deA^ima'
told that in North America, efpecially about Hudfon’s Hbm Hie-
bay, mefopitiiyi,
p. IC. -
52°
Of Slcfp ;
and Torpor.
3<Si
<Of man.
362
Principal
phenomena,
of hiberna¬
tion.
363
Sufpended
animation
of feme ani¬
mals.
P H Y S I
bay, fifties are not unfreguently found included within a
body of ice, and when expofed to gentle heat, have re¬
covered life and motion.
Almoft all infers remain, during the winter, in a tor¬
pid ftate. This happens principally to the chryfolites,
and fuch grubs as canriot, in that feafon, procure their
food.
It will appear extraordinary that we Ihould place man
.among the hibernating animals $ and yet there feems lit¬
tle doubt, that even he is capable of having his life fu-
fpended for a confiderable time, when expofed to thofe
caufes which bring about the torpidity of thofe animals
that vre have already mentioned. We are told of a wo¬
man who, in February 1789, remained eight days
buried in the fnow, and ftill recovered j and the cafe of
the three women who remained for 37 days in a liable
at Bergamoletto, that had been overwhelmed by an
avalanche, or fnow heap, with no other fuftenance than
the milk of a half-llarved (he goat, is well known.
Thefe inflances, added to others of perfons who have
paffed feveral weeks in a Hate of almoft uninterrupted
lleep, tend to prove that man himfelf may, under certain
circumftances, continue in a torpid ftate.
During this ftate of torpidity, the animals fcarcely ap¬
pear to live } fenfation feems altogether loft j their irrita¬
bility is fo much diminilhed, that they may be cut, torn,
or even broken to pieces, without exprefling any mark
of feeling, or giving any fign of motion ; digeftion feems
entirely fufpended •, the fecretions and excretions are dif-
continued. Some of the functions, however, are carried
on. Refpiration and circulation, though very languid,
and fometimes fcarcely perceptible, appear to go on in
a degree fufficient to preferve the exiftence of the animal \
and the aftion of the abforbents feems to be very little
diminiihed, as appears from the gradual abforption of the
fat. If the animal is taken from its place of confinement,
and expofed to a gentle heat, it gradually recovers all
its faculties ; but if carried back to its cell, it relapfes
into the ftate of torpidity.
The long fufpenfion of animation, of which feveral
animals are fufceptible, appears ftill more extraordinary
'than the torpidity above defcribed. The common hair
worm Cgordins aquaticus) may, when dried, be pre¬
ferred for an indefinite length of time, and when put
into water, gradually recovers its ufual aftivity of mo¬
tion. See Helminthology, N° 32. One of the moft
remarkable cafes of this fufpended animation is that re¬
lated of the garden fnail, of which the following curious
account has been given in the Philofophical Tranfaftions
for 1774. Mr Stuckey Simon, a merchant in Dublin,
whofe father, a fellow of the Royal Society, and a lover
of natural hiftory, left to him a fmall colleddion of fof-
fils and other curiofities, had amongft them the (hells
of fome fnails. About 15 years after his father’s death
(in whofe poffeflion they were many years), he by
chance gave to his fon, a child about 10 years old,
fome of thefe (hells to play with. The boy put them
into a flower-pot, which he filled with water, and the
-next day into a bafon. Having occafion to ufe this,
Mr Simon obferved that the animals had come out of
their (hells. He examined the child, who allured him
that they were the fame he had given him, and faid he
had alfo a few more, which he brought. Mr Simon
put one of them into water, and in an hour and a half
after obferved that it had put out its horns and body,
O L O G Y. Chap. XV.
which it moved but (lowly, probably from tveaknefs. Of Sleep
Major Valiancy and Dr Span were afterwards. prefent,and Torpo-.
and faw one of the fnails crawl out, the others -being
dead, mod probably from their having remained - fome
-days in the Water. Dr Quin and Dr Rutty alfo exa¬
mined the living fnail feveral times, and were greatly
pleaf’ed to fee him come out of his folitary habitation
after fo many, years confinement. Dr Macbride, and a
party of gentlemen at his houfe, were alfo vvitneffes of
this furprifing phenomenon. Dr Macbride has thus
mentioned the circumftance ; “ After the (hell had lain
about ten minutes in a glafs of water that had the cokl
barely taken off, the fnail began to appear $ and in five
minutes more we perceived half the body puftied out
from the cavity of the (hell. We then removed it into
a bafon, that the fnail might have more fcope than it
had in the glafs j and here, in a very (hort time, we
faw it get above the furface of the water, and crawl up
towards the edge of the bafon. While it was thus mov¬
ing about, with its horns eredt, a fly chanced to be
hovering near, and, perceiving the fnail, darted down
upon it. The little animal inftantly withdrew itfelf
into the (hell, but as quickly came forth again, when it
found the enemy was gone off. We allowed it to wan¬
der about the bafon for upwards of an hour, when w:e
returned it into a wide-mouthed phial, wherein Mr
Simon had lately been ufed to keep it. He w>as fo
obliging as to prefent me with this remarkable (hell;
and I obferved, at twelve o’clock, as I was going
to bed, that the fnail was ftill in motion, but next morn¬
ing I found it in a torpid ftote, (ticking to the fide of
the glafs.”
The ftill more extraordinary inftances that have been
related, on what many have confidered authentic tefti«
mony, of toads having been found inclofed in the trunk
of a large tree, or within a folid block of (lone, appear
almoft incredible $ and yet if we confider that M. He-
riffant preferved toads in a ftate of fufpended animation
for 18 months, in boxes covered with a thick coating
of mortar (fee Erpetology, p. 286.) ; that the fnails
mentioned in the above quotation, mull have lain for at
lead 20 years ; and that flies have been recovered after
being immerfed for many months in Madeira wine, it is
difficult to fay how long this fufpended animation may
not be continued.
3<*4
Similar phenomena take place in the vegetable crea- Hiberna¬
tion. Moft of thofe plants which furvive one year, non of
(hed their leaves on the approach of winter 5 and, dur- P^n**-
ing this feafon, the motion of the fap ceafes, and they
have all the appearance of dead (hrubs. The herba¬
ceous tribes even die down to the roots, which, being
moftly of the bulbous kind, afford (belter to the furviv-
ing germ } and are hence called, by botanifts, the hyber-
nacula of plants. On return of fpring, the plant (hoots
anew from its winter’s retreat, and flourithes with its
former ftrength and beauty.
Some plants are even capable of having their vitality,
or rather the exercife of all their functions, fufpended,
as in the gordius and the fnail, for an indefinite length
of time. MoJJes have been kept in a dried ftate in
a hortus Jiccus for many years, and have (hown no fign
of life, till they were moiilened and expofed to air,
light, and a moderate heat, when they have recovered
all their powers, have erefted their ftems, (hot forth
new branches, and ffourilhed as at firft.
It
Chap. XV.
Of Sleep It is. almoft irnpoffible, in the prefent ftate of our
a:;;l i'orpor.phynological knowledge, to give any rational theory of
thei'e phenomena. The torpor of animals has been at-
Theory of tributed to exhaufled excitability, or exhauited fenforial
torpor." power j to the effefls of habit, and to the effect produ¬
ced on the brain by fufpended or diminithed refpiration.
The laft of tlrefe, though wot quite fatisfa£lory, appears
to us the moft probable hypothecs. It has been ably de¬
fended and illuftrated by Dr George Kellie, in a paper in
which he relates a remarkable cafe of torpor from cold.
“ The powers of voluntary motion and of fenfation
(fays Dr Kellie), are known to depend immediately up¬
on the conditions of the brain and nerves •, if, therefore,
we could difcover in what manner thefe organs are af-
fetted by any of the preceding ev'ents, we fhould advance
conliderably towards the folution of the queftions above
ftated. {Namely, What is the order of fuccejjion be¬
tween the diminijhed irritability of the heart, in confe-
quence o f the abjlraEtion of caloric, and the complete tor¬
por of the voluntary mufcles and of the organs of fenfe,
and how are the intervening effects connected?') Were the
inactivity of thefe organs the direft effect of their dimi¬
nished temperature ; did the torpor in no cafe happen, till
the heat of the brain and nerves was reduced beneath
the natural ftandard, there could be hardly ground for
any farther inquiry. But, as it is not fo, fome other
change, lefs direfl, mutt have occurred, in confequence
ot the connexion of the brain with, and its dependence
upon, fome other of the funflions antecedently and more
immediately affefted *, and this function I apprehend to
be relpiration, between vrhich and the energies of the
nervous fyftem a very intimate connection is maintained,
through the changes produced on the blood during the
pulmonary circulation. This dependence of the brain
upon the properties of the blood, maintained by refpira¬
tion, is evinced by a great variety of obfervatiens.
w hatever impedes the refpiratory changes of the circu¬
lating fluid debilitates or deftroys the powers of mufeu-
lar motion, as the refpiration of noxious gafes, of reduced
or rarefied atmofphere ; while greater exertions of muf-
cular powers call for, and give occafion to more fre¬
quent refpiration, more rapid confumption of air, and
greater changes of the. blood ; and the breathing of
more effedlive gafes, as of the nitrous oxide, increafes
the motive and fenfitive powers of animals. That thefe
effedts depend immediately upon the properties of the
blood, as modified by relpiration, adling on the brain
has, I think, been proved by the experiments of Bi¬
chat, who, in a mafterly manner, has traced the mu¬
tual connedfion and dependencies of the vital functions
xn his admirable Recherches Physiologiques fur la Vie. et
la Mart. The transfufion or injedlion of venous blood
into the carotids induced afphyxia or death, the inflant
it reached the brain ; an effcdl which did not follow the
. fimilar transfufion of arterial blood from the carotid of
Recht-r*' anot^er *• By thefe experiments, and by feveral other
ches, partii. phfervations, he has thewn, that the afphyxia which fo
art. 7. m!tantly follows impeded or fufpended refpiration is oc-
cafioned by the impreffion of dark, venous, unchanged
blood upon the brain, and not, as has commonly been
fuppofed, from this blood being incapable of llimulating
the left fide of the heart, which, on the contrary, con¬
tinues to contract and to circulate the blood for fome
time after the voluntary functions are fufpended ; an ob-
fervation confirmed alfo by Coleman and others.
Vol. XVI. Part II.
521
“ Such then appears to be the connection between the Of Sleep.
- funClions of refpiration and thofe of the brain. Now, ar.ci terpo;-.
in animals rendered torpid from cold, there are many
obfervations which lead us to believe, that the immobi¬
lity of the nervous fyftem depends much, and very di-
reftly too, on the ftate of refpiration.
“ In the perfect torpor of the hibernating amphibia-,
refpiration is completely fufpended, and the confequent
changes produced on the blood by that funCtion totally
prevented. This, which appeared from a variety of ob¬
fervations on the winter quarters of luch animals found
imbedded in mud, incafed in ice, or clofed up in oper-
cula of their own eonftruction, for the occaficn of ex¬
cluding the air, has been amply confirmed by the pointed
experiments of Spallanzani, lately publiftxed by Senebier f. j. Mem. cn
“ In every cafe of torpor from cold, where the rei'pira- Ref ira-
tion falls ftxort of this complete iufpenfion, it is at leaft bow.
more or lefs impaired. How much the torpid ftate de¬
pends on this condition of the refpiratory funClions,
farther appears from obferving, that hibernating ani¬
mals, even thofe not of the amphibious order, warned
by the approach of winter, inftinClively or induftrioufly
feek fituations unfavourable to perfeCl refpiration, where
this function may be either inadequately or not at all
performed, as by premature and involuntary interment
under ground, in old walls, in mud, at the bottom of
lakes, &c. The inftinft of thefe animals, too, has
been finely imitated by experiment, illuftrating at once
the objeCt of this inftinCt, and confirming the opinion
here advanced of its tendency. Thus the dormant
hamfter was found to regain and preferve its activity,
when freely expofed to a pure atmofphere, the tempera¬
ture, at the fame time, not exceeding that at which it
had formerly become torpid, or at which it relumed to
that ftate when again fecluded under ground |. Thefe . p .r
obfervations feem conclufive on this point, and, with MaUlliJl.
thofe already brought forward confirming the general by Smeliie,
connection eflablilhed between the properties of thevoLvii-
blood, as modified by refpiration, and the funClions ofp‘ I5'5‘
the brain, render it, I think, highly probable, that the
torpor of the voluntary powers, in the cafes now under
confideraiion, is the confequence of a limited and im-
perfeft refpiration, antecedently induced by dimini (bed
temperature.
Obfervation, indeed, is more deficient on this point
with regard to the higher orders of animals, and to men,
who only occafionally become torpid from cold. Yet
more than analogy, which is here very ftrong, leads me
to believe that, even in thefe, the fun&ions of refpira¬
tion are much and neceffarily affeCled. The examples
of cattle and of men remaining long torpid, deeply buried
under fnow, are pretty direft and convincing proofs of this.
“ If our induction from all thefe obfervations be admit¬
ted, we have the rudiments of a theory adequate to the
explanation of the phenomena, in fo far, at leaft, as the
torpor of the voluntary powers is concerned.
“ From the fufpended or imperfeCt refpiration, thofe
changes, by which the blood is fitted for maintaining
the aClivity of the fenforial fyftem, are interrupted^
this imperfeCt blood circulating ftowly through the brain
direCtly impedes its functions, and fo debilitates the ex¬
citability of the motive and fenfitive organs, that they
become torpid. This enunciation may feem hypotheti¬
cal ; but let the proofs of the intimate connection be¬
tween the reipnable and fenfonal functions be weighed ’
3 II confider
P H Y S I O L O G ,.Y.
3
c8.
^22 P H Y S I
OLgleep confider alfo lilie ialerrupted refpiratxon of hibernating
fl»d Torpor. anc} torpid animals, their inilinfts with regard to this,
and the greater facility with which torpor is induced in
a confined fituation, which they naturally feek } and
compare all thefe with the obfervations and experiments
of Bichat on the effefts of the immediate impreflion of
venous blood upon the brain, and you wiK perceive a
conneded fyftem, not entirely fanciful, a theory not
without foundation and drength, and which appears to
* Edin. me at lead to merit feme attention
Med. and For further particulars refpefting the torpidity or hl-
U-urg. Jour, beriiation of animals, we refer the reader to Spallan-
’■ zani’s Tra&s on Animals and Vegetables i White’s isalu-
ral Hiflory ofSelborne; Barton’s Fragments of the Natu¬
ral Hijlory of Pennfylvania ; Pennant’s ArBic Zoology ;
La Cepede on Oviparous Quadrupeds, as tranfated by
Kerr; Townfon’s Tra&s on Natural Hiflory and Phy¬
siology, and the Inaugural Differtation of IV Reeve de Am-
maiilus Hieme Sopitis, publiihed at Edinburgh in 1803.
Chap. XVI. Of Death.
In the article Man, (N° 33. to the end') we have
traced the pregrefs of human life, from the cradle to
the grave; and have briefly confidered the phenomena
and the confequences of natural death. In that article,
and LONGEVITY, we have alfo ilated the natural dura¬
tion of human life, and the circumftances that tend to
prolong our exiftence beyond the ordinary period. We
fhall not here enter again on any of thefe topics, except
to give a more ample account of the gradual approaches
of natural death, and (hall then enumerate the caufes
which ufually produce violent or accidental death, and
mention the opinions of fome of the belt writers on the
nature o£ death.
Natural death is, in the prefent date of civilized fo-
by no means a common occurrence. When it
S'«
3*7
SrsuhiaJ
approach of ciety
natural
rlefeth.
does take place, its approach is dow and gradual. He
whofe life terminates in confequence of advanced age,
(to ufe the language of a celebrated French phyfiolo-
gid), dies in detail." His external functions fucceflively
ceale to exert their action ; all his fenfes are fucceflively
lod, or the ordinary caufes of fenfation pafs over them
without leaving their ufual impreflions. The fght be¬
comes obfeure, and at length the humours of the eye
no longer tranfmit the rays of light; the ear receives
only confuted founds, and frequently before death, is
altogether infenfible ; the fenfe of touch, in confequence
of the hardnefs and calloufnefs of the cuticle, and the
obliteration of many of the fubcutaneous veffels, grows
dull and uncertain •, and all the parts depending on the
flein {how marks of weaknefs; the hair and the beard
grow white, and a greater or lets degree of baldnefs
takes place •, odours are no longer perceived, or they
are perceived but faintly. The tade ufually fuivives
the red of the fenfes ; but that too, at lad, grows equally
obfeure. The functions of the brain partake of the
imbecility of the external fenfes. The imagination in
particular becomes dull and often depraved •, the memory
no longer retains thofe occurrences which are every day
taking place, though it recalls with increafed relith and
delight thofe of pad times 5 the judgement becomes
weak and wavering.
From the univerfal agency exerted by the nervous
fyftem on all the animal functions, we mud expeft that
O L O G Y. Chap. XVI.
when the former is impaired, the latter will fee proper- Of Death,
tionally enfeebled. The faculties of locomotion and of v
fpeech are commonly the fird of thefe that fail 5 the
body totters at every hep, the voice grows weak, and
the tongue faulters. The motion of the limbs is diffi¬
cult and painful, and hence is but feldom willingly ex¬
erted. Not fo with the vocal organs, though the im¬
pediments to utterance are evident and painful to his
hearers, the old man kimfelf feems fcarcely to attend t«
them, but talks with proverbial garulity, and efpecially
delights in recounting the feenes and a&ions of his youth.
While the external funftions, and thofe of the brain, are
thus gradually impaired } the internal, or what are com¬
monly called the vital and natural funftions, as digedion,
abforption, circulation, refpiration, and fecretion, proceed
with but little derangement. The circulation and re¬
fpiration are indeed flower than before, and the appetite
is in general Ids keen and returns lefs frequently; but
the digeilive powers of the gaftric fluids remain in full
vigour j and even after death has taken place, are ex¬
erted on the coats of the ftomach 5 abforption is alfu
very a&ive, and nutrition, at lead in many parts of the
body, is fufficiently evident. At length, however, all
thefe fundions lole their powers} digedion languiihes }
the fecretions no longer take place ; the circulation,
efpecially in the minute veffels, becomes obfeure, and
being deprived of the tonic powers by which it was * ^
carried on, gradually ceaies altogether *, the heart no rs,
longer propells the blood from its ventricles; and the cherches
circulation through the lungs being thus arreffed, thefe Pbyfiol.
organs ceafe to take in air, make their laft expiration,
and thus the natural life of man is terminated *. 368‘
Accidental death takes place in one of the two fol- Accidental
lowing ways j either fuddenly, in confequence cf fome or violent
great didurbance produced in the animal economy, as‘Ieatb*
when a man is cut off by a hidden droke of apoplexy,
violent haemorrhage, afphyxia, &c. «*r by dow and
gradual fteps, in confequence of fome lefs violent but
iiill fatal difeafe. In the former cafe, it is fuddtn or
violent death •, in the latter lingering death.
Violent death may take place fird, either in the brain,
the lungs, or the heart; but when the a&ion of one of
thefe organs ceafes, that of the others foon terminates.
The entire reflation of life feems, however, to be more
hidden in the two latter cafes, and mod of all in the
lad *, when the heart is wounded or ruptured, the ani¬
mal dies indantly ; when the lungs are rendered inac¬
tive in confequence of fuffocation, the animal may live
for feveral minutes, or for an hour or two ; but when
the brain is overwhelmed, he may furvive for hours or
even days. Thus it fometimes happens, in cafes of
apoplexy, that the patient lies motionlefs, fpeechlefs, and
quite infer Able to external dimuli, while the circula¬
tion and refpiration continue, impeded indeed, but not
dedroyed, for a confiderable time, though life, as ap¬
pears from the event, be in a date of irrecoverable de-
clenfion. We (hall prefently thow how thefe circum-
dances have been explained.
The ufual figns of approaching death are, a very
quick and fmall pulfe, fcarcely didinguithable, and com¬
monly intermitting; Coldnefs, and generally clammy
fweats about the" extremities; a “ lack In Are” eye,
funk in features, want of exprefiion about the counte¬
nance, and a prominence of the bones of the face, with a
correfponding hollownefs in the cheeks, orbits, and
efpecially
/
actual
death.
Chap. XVT. P H Y S I
Of Death, efpecially at the temples. Thefe laft appearances con-
'   ftitute the marks of what has been called facies Hippo-
Sioarafa erotica- They are all figns of a lofs of activity and
poaching power in the circulating and nervous fyftems. Under
death. thefe bodily circumftances, the powers of the mind
feem to decline, generally with an equal pace with
thofe of the body; and when the medium through
which the activity of the foul is manifelled can no long-
el- aft, we cannot expeft to find any further traces even
of its exiftence. Yet at the period of its feparation,
we are told of brilliant mental exertions of powers of
intelleft, not equalled in the belt portion of exiltence.
It has not been our fortune to fee fuch intelledtual
animation. At the moment of death, anxiety for thofe
we have loved will fometimes occafion apparently dif-
proportioned exertions ; and as they were unexpected,
they have been exaggerated. But in no inltance could
we ever deleft the aftivity of mind independent of the
* New body. To this temporary prifon the foul is confined,
Land. Med. til], by the deftruftion of the machine, its animating
Di:l. vo.. i. pfbiciple is emancipated, foaring probably in higher,
and, we trull, in more blifsful, regions *.
Sign? or A few cafes have occurred, in which perfons, who
criterion of were thought dead, have recovered from what was real¬
ly a Itate oifufpended animation ; and there is reafon to
believe, that fome unhapoy beings have been buried
while in this feemingly lifelefs date. It becomes, there¬
fore, a matter of the highed importance to afeertain,
with certai’nty, whether or not death has actually taken
place. The ordinary figns of death, as enumerated by
one of the lated writers on this fubjeft, are as follow:
l. 'Wit fufpenfon of refpir at ion. 2. The rigidity of the
limbs. 3. The /ofs offenjation and motion. 4. The want
of pulfation in the heart and arteries. 5. ’W\t fpontaneous
dife barge offeces. 6. The col lapfe, opacity, and want of
luf re in the eyes. 7. The coldnefs of the body. 8. The
palenefs or lividity of the countenance. 9. The relaxation
of the lower jaw. 10. The regurgitation of liquids to
the mouth, n. The infenfbiUty of the pituitary mem¬
brane of the nofe. 12. The collapfe, foftnefs, and
wrinkling of the lips. 13. The hollownefs of the temples,
and tlnnnefs and contraction of the nofe. 14. Put refaction if.
Mod ox theie figns fingly have been fhown to be falla¬
cious and none of them, except the lad, are to be depend¬
ed on with implicit confidence. Dr Davis recommends
the following mode of procedure. “ As foon as the
evident figns of life ceafe, let us place the body in a
warm or dry bed, give a proper temperature to the air
of the apartment, and employ every means for re-
ftoring it to life. If we judge, from the nature of the
difeafe which preceded the death, that thefe means are
ufelefs, we may content ourfelves with keeping the bo¬
dy, until its decompofition become manifed •, but let us
never abandon an unfortunate perfon, who, perhaps,
by perreverance in the proper means, may be redored to
life :• diould he recover, he will be a living monument
of unexpefled refurreidion, and of the unceafing efforts
of humanity. If a perfon die of malignant fever, feur-
'Y'y, internal inilammation, or any other difeafe which
f Bains
Reglement
eoncernant
les dices,
part ii
CLOG Y. 52-3
corrupts the fluids, foon after death the beily becomes Of Death,
black and fwelled; black or livid fpots appear on the limbs —
and back, the eyes become hollow and foft, and dis¬
charge a puriform duid ; the eyelids grow yellow ; the
mouth opens, becaufe the lower jaw is relaxed \ the fkia
gets foft, the mufcles daccid ; and, ladly, the whole
body exhales a putrid odour. All theie phenomena
united, conditute an infallible proof of real death * IHd,
The changes which the animal body undergoes in con-
fequence of death, and during putrefadfion, have ble-n
amply detailed and explained under CHEMISTRY,
chap. xix. fedl. 2. --i
In treating of the general phenomena of life in the Comnara*-
£rd chapter of this article, we made a few obfervationsd^. PefH-
on the degree of vitality that appears in various tribes
of organized beings. There is fcarcely a more curious
part of the phyfiology of death than the confideration of
the greater or lefs difficulty with which it is produced
in different animals. Some, as the herring and the
whiting, die almod indantly on being removed from the
fituation in which they ufually live. Some are killed
by a flight bloxv on the nofe or the neck 5 this is the cafe
with the feal, the rat, the hare, and the rabbit. Others
again retain life with great pertinacily. Among the
mammalia, the cat is proverbial for being difficult to
kill ; the floth has been known to live for above 40
days clinging to a pole, and entirely without food ; and
Dr Sparrman affures us, that the rat el, or honey weazle
(viverra meUivord), is fo hardy that it is almoit im-
poffible to kill it; the colonitts and Hottentots both
affert, fays he, that it is almott irnpoffible to kill this
creature, without giving it a great number of violent
blows on the nofe; and it is remarkable that fuch a
number of hounds as are able colleflively to tear in
pieces a lion of moderate fize, are lometirnes obliged to
leave the ratel only apparently dead f. Some fithes f Sparr*
live for a long time after being removed from the wa-auiri's Voy-
ter, and even after being gutted and cut in pieces, as theadf'
carp, the founder, and the eel. It is among the reptiles,
mollufca, and zoophytes, however, that we find the
moft remarkable inftances of pertinacity of life. Re¬
ferring the reader to the article Erpetolcgy for theie
inftances in reptiles, and to Helminthology for thofe
in zoophytes, we fhall here only mention two among
mollufca. The fea marigold f acli/iia calendula) is de-
ftroyed with fuch difficulty, that after drilling the holes
of the rock from which they appear, with an iron in-
ffrument, they have been known to rife again in the
fame places, and become as numerous as before in the
courfe of a few weeks t- Snails whofe remarkable}
fufpended animation we have already recorded, may be Nat. Hi/h
cruthed beneath the foot, and will yet furvive, and re-°j -
pair the breaches in their fhelly covering ; nay, they Ct0€i‘
are capable of paffing the ordeal of boiling water, as
we learn from the relation of a lady who, wanting fome
fnail ihells for a piece of grotto work, attempted to kill
the animals by repeatedly pouring over them boiling
water ; but to her horror and aftonifixment, fhe obferved
them next day crawling about the edges of the veffel
3 U 2 in
(n) The work of M. Bruhier, fur l'Incertitude des Signes de !a Mart, from which thefe remarks of Dr Davis
appear chiefly to be taken, created fo much alarm in France, that every body dreaded being buried alive. To
Combat thefe terrors, M. Louis, in 175?- publifhed his Lettres fur la Certitude des Signes de la Mart; in which lie
has very happily, and we think fuccefsfully, refuted the arguments of Bruhier, and has thereby relieved th mind?
&is readers from one of the moft dreadful apprehenfions that can appal us on tins fide the grave.
52+
PHYSIOLOGY.
Cliap. XVI.
Of Death.
* Annual
RegifterZ
vol xviu
p. S6.
311
Caufes of
death.
in which fhe had fcalded them *. It is in vain for us
to attempt any explanation of thefe extraordinary phe¬
nomena. We mull refer them to feme principle in the
animal economy which is at prefent unknown.
The remote caufes of death have been, by Dr Ontyd,
arranged under 12 general heads, to which he gives the
name of cla/Jes. Thefe we lhall enumerate, with their
principal fubdivifions.
I. Death arifing from the mechanifm of the body.
II. Death from the paffions of the mind.
I. Excitingpajjions ; 2. DepreJJingpajlions.
III. Death from fuperabuiidance or deficiency of
heat.
* Ontyd
o?i Mortal
Dfeafes.
373
How thefe
wperate.
I. From fupci-abundant heat $ 2. From deficient heat.
IV. Death from eleffricity.
V. Death from noxious gafes.
I. From hyperoxygenmedgafies ; 2. From deoxyge-
ni%edgafies ; 3. From peculiarly Jiimulating gafies.
VI. Death from poifons.
1. Animalpoifions ; 2. Vegetable poifions ; 3. Mine¬
ral poifions.
VII. Death from univerfal difeafe.
1. Fevers; 2. Febrile dfieafies (exanthemata).
Thefe feven claifes are fuppofed to produce death by
the immediate extinction of the vital principle ; the five
following are fuppofed to effeCt this by fuppreffing the
addon of fome vital organ, or by difordering the chain
of tire vital powers by deftroying the addon of fome of
the intermediate links.
VIII. Death from inflammations.
I. Inflammations of the head; 2. Of the bread;
ofi Of the belly.
IX. Death from fluxes.
x. Alvine fluxes ; 2. Hemorrhages.
X. Death from cachexies.
x. Jjleers ; 2. Atrophies ; 3. Debilities and Priva¬
tions.
XI. Death from difeafes of the nervous fyftem.
1. Atony ; 2. Spafim.
XII. Death from difeafes of the fecretory organs.
1. From altered action ; 2. From altered Jlruc-
ture *.
The manner in which thefe caufes operate in termina¬
ting life, is thus dated by the fame author.
The caufes of theyfr/? clafis ad by inducing too great
a rigidity of the folids, and by rendering them infenlible
to Jlimuli; the neceffary effeds of the continued adion
of the powers of life. In death from caufes of the fiecond
clafis, the perfon dies in confequence of apoplexy, fiyn-
cope, m fufifocation, the brain, the heart, or the lungs
being overwhelmed by accumulated blood. The caufes
of the third clafis ad in a fimilar manner with thofe of
the fecond •, that of the fourth by fuddenly extinguifh-
ing the vital principle ; thofe of the fifth always ad by
px&ucmgfujfocation. The caufes of the fixth clafs ad
in four ways : 1. By abolilhing the vital principle by
the violence of their Itimulus) 2. By deitroying the ac¬
tion of the brain, the heart, or the lungs j 3. By pro¬
ducing mortification of the inteftinal canal ; 4. By fe-
cretly and infenfibly deftroying life. Thofe of thefie-
venth clafs ad in fix ways: 1. and 2. As in the laft;
3. By local inflammation ) 4. By mortification of fome
vital organ ; 5. By a change in the organic ftrudure of
the inteftinal canal inducing a colliquative diarrhoea;
q. By colliquativefivoeats wafting the body.
The caufes of the eighth clafs ad in four way s: 1. By Of Death.
inducing violent convulfions ; 2. As in the two laft ; 3.  v—
By fupprefling the adion of lome vital fundion from the
violence of the inflammation ; 4. By mortification. The
ninth clais may ad in five modes : 1. Bv fpafim ; 2. By
iatal fiyncope ; 3. By impeded adion of lome vital organ ;
4. By mortification or fiphacelus; 5. By waiting the
ftrength in fruitlefis exertions. The tenth clafs may ad
in no lefs than nine ways: 1. By the confumption of
fome vital organ, or deftroying the tone of the whole
body; 2. By the violence of the noxious ftimulus j
3. By fuffocation ; 4. By apoplexy ; 5. By fiyncope;
6. By hemorrhage ; y. By colliquative diarrhoea ; 8. By
mortification of fome organ } 9. By malignant fever
from ablorbed ichorous matter. The caules of the
eleventh clafs ad only in twro wrays : 1. By violent
fpaim 5 2. By apoplexy. Thofe of the twefth clafs, pro¬
duce death in three modes : 1. By the flow' effeds of the
noxious ftimulus; 2. By the continually ftimulating no¬
xious power alone, or by this and the continual w’afting
of the blood, to form fome peculiar fecretion ; 3. By im¬
peding or deftroying the fundion of a vital organ *. %
Many of thefe modes of operation are very ill defin-p.
ed, and they may all be reduced to about eight or ten,
or perhaps even fewer.
Death has been defined the feparation of the foulfrom Nature 0f
the body -f ; the extinction of the vital principle ; the ex- death.
tinc.iion of the faculty of anfiwering ajlimulus f, &c. &c. { if oh nfon.
Perhaps w7e cannot deferibe it better than by calling it* ^ntyd-
the irrecoverable cejfiation of all the bod ill/ functions. By
this charader xve diftinguiih it from jfufpended anima¬
tion and lethargy, in which fame of the fundions conti¬
nue ; while we acknowledge the furvival of the iminii
terialpart of our frame.
It has been the general opinion among philofophers,
both of ancient and modern times, that death produces
Ontyd,
(>31-
only a change of the elements or principles of the or¬
ganized body •, and does not effed the annihilation of
any part. Modern chemiftry has fully confirmed this
opinion, and has fhovn that by putrefaction the body is
diffolved into a few7 earthy,fialine, and gafieous produds,
all capable of en tering into new combinations, and thus
conftituting a part of future bodies. See Chemistry,
N° 2572, and Man, N° 44.
Of all the writers on the nature and phenomena of
death, with whom we are acquainted, none has treated
the fubjed with fuch accuracy and philofophic method,
as Bichat. With a fummary of fome of the leading prin¬
ciples of this able phyliologift we lhall clofe the pre¬
fent chapter, and thus terminate our phyfiologicai en¬
quiries.
We have already mentioned Bichat’s divifion of life Opinions of-
into/jw/wz;/and organic: fee N° 49. Proceeding on Bichat,
the principle of this divifion, he conceives that the two
lives terminate in different ways, and that one often ter¬
minates while the other remains adive. In the natural
death that happens from old age, the animal life gra¬
dually ceafes in the order we have deferibed, N°367,
while the organic life remains. The fame happens in
thofe cafes of violent death where life firft ceafes in the
brain, this organ being the centre of animal life. In
other cafes of violent or accidental death, the organic
life firft ceafes in its central organs, the heart or the
lungs ; but in thefe cafes, the animal life alfo is fpeedily
fupprelTed.
It
TABLE
[To face page 525. Vol. xvi.]
OF THE MOST IMPORTANT CIRCUMSTANCES
RESPECTING THE
ORGANIC FUNCTIONS
OF THE
HUMAN BODY.
1. ORGANS.
2. FLUIDS.
3. raF.NOMENA.
I. SENSATION.
Cerebrum, Cerebellum, Medul¬
la Oblongata, Spinal mar¬
row, Nerves, Organs of
Senfe.
Lymphatic and Gelatinous
fluids, Nervous fluid ?
Senfation, A£lion of external
bodies on Man, and Per¬
ception of thefe Adlions.
II. MOTION.
Mufcles, Tendons, Bones,
Cartilages, Ligaments, and
Mucous bagsi
Gelatinous fluijl, Synovia,
Marrow, Lymph, and
Blood.
Contraction, Dilatation, Lo¬
co-motion, Progreflion.
ACtion of Man on exter¬
nal objeCts.
III. DIGESTION.
Salivary glands, Mouth,
Teeth, Gullet, Stomach
and Inteftines, Liver, Pan¬
creas, and Spleen.
Saliva, Gaftric juice, Pan¬
creatic juice, Bile, Mu¬
cus.
IV. ABSORPTION.
LaCteals, Lymphatics, Tho¬
racic duCt, Mefenteric
glands, Lymphatic glands,
Skin.
Chyle, Lymph, Serous fluid.
Maftication, Deglutition, Di-
geftion in the ftomach and
inteftines. Mutual Ac¬
tion of Alimentary fub-
ftances and the Digeftive
organs.
Imbibition, ACtion of the
Lymphatic veffels and
glands on the fluids, Sepa¬
ration of noxious or ufelefs
matters, and Selection of
ufeful fubftances.
V. CIRCULATION.
Heart, Arteries, Veins, and
Exhalants.
Blood, Lymph, and various
exhaled and fecreted fluids.
Contraction, Dilatation, Pul-
fation, Exhalation, Nutri¬
tion.—Mutual aCtion be¬
tween tjie Blood and Cir¬
culating fluids.
VI. RESPIRATION.
Noftrils, Larynx, Windpipe,
Lungs, and Diaphragm.
Blood and Mucus.
VII. SECRETION.
Salivary glands, Liver, Pan¬
creas, Kidneys, Tejles,
Mucous glands, Mem¬
branes, &c. Miliaryglands,
Brain ?
Tears, Mucus, Saliva, Gaf¬
tric juice, Pancreatic juice,
Bile, Lymph, Synovia,
Fat, Marrow, Cerumen,Se¬
men, Urine, Milk, Ner¬
vous fluid ?
VIII. REPRODUCTION.
Penis, Tefticles, Vejiculee
Seminales, Proftate gland,
Spermatic veffels in Man $
Vulva, Vagina, Uterus, and
the Mammce, in Woman.
Semen, Mucous fluid, Profta-
tic fluid, Liquor amnii, and
Milk.
Purification of the fluids, Re¬
newal of aCtion, Animal
heat, Mutual aCtion be¬
tween the air and the
animal folids and fluids.
Separation of fluids ufeful in
the economy, and Expul-
fion of noxious or ufelefs
parts.
Copulation, Conception, Par¬
turition, Ls&ation.
4. POWERS.
Senfibility and Vital refift-
Irritability, ConiraCtility, and
Vital refiftance.
Diffolution, Aflimilation, and
Vital refiftance.
Irritability, Contractility, Af-
fimilation, and Vital refift-
Elafticity, Irritability, Con¬
tractility, Dilatability, and
Vital refiftance.
As in Circulation.
Various.
Generative power.
RELATIVE PREDO¬
MINANCE.
Moft predominant in infan¬
cy ; female fex; melancho¬
lic temperament; hypochon¬
driac, hysteric, and other
nervous affeCtions, and in
warm climates.
In manhood; in the male
fex j the fanguine tempe¬
rament, and in mountain¬
ous countries.
In infancy; in the female
fex 5 in the fanguine tem¬
perament j in cold wea¬
ther and cold climates.
In childhood; in the fanguine
temperament; in warm
climates j and dmmgjleep.
In childhood; in the female
fex $ in the fanguine tem-
peramertt 5 in warm coun¬
tries y and in febrile and
inflammatory affeCtions.
Much as in Circulation.
In middle age 5 various as to
fex and temperament 3 in
warm climates.
In youth ; in thofe of a fan¬
guine temperament, and
lively imagination.
6. PRINCIPAL MORBID
AFFECTIONS.
Vertigo, Coma, Delirium,
Infanity.—Pain, Itching,
Want of feeling 3 Ageuf-
tia; Tinnitus aurium, Deaf-
nefs 3 Intolerance of light,
Dyfopia; Caligo, Amau-
rojis.
Spafm, Convulfion, Twitch¬
ing, Paralysis.
Bulimia, Pica, Naufea, Fla¬
tus, EruCtation, Rumina¬
tion, V omiting, Heartburn,
Pyrexia, Anorexia.
Glandular obftruCtion, Ato¬
ny of lymphatics.
General fever, Palpitation,
Plethora, Inanition, De¬
bility, Syncope.
Yawning, Sighing, Sobbing,
Hiccup, Sneezing, Cough¬
ing, Anxiety, Dyfpncea,
Stertor, Afphyxia, Dumb-
nefs.
Increafed fecretion,Diminiih-
ed fecretion, Depraved fe-
cretion, Jaundice, Calcu¬
lus, &c.
Priapifmus, Satynafls, Nym¬
phomania, Menorrhagia,
Amenorrhcea, Impotence,
Sterility.
#
e 525- Vol. xvi.]
i. ORGANS.
2. FLUIDS.
I. SENSATION.
Cerebrum, Cerebellum, Medul¬
la Oblongata, Spinal mar¬
row, Nerves, Organs of
Senfe.
Lymphatic and Gelatinous
fluids, Nervous fluid ?
3. PHENOMENA.
Senfation, Adlion of external
bodies on Man, and Per¬
ception of thefe Adions.
II. MOT REPRODUCTION.
Mufcles, fend, Tefticles, Vejiculee
Cartilages, Proflate gland,
Mucous bagstrmatic veffels in Man j
Iva, Vagina, Uterus, and
: Mamma', in Woman.
Gelatinous fluy; Mucous fluid, Profta-
Marrow, L duid, Liquor amnii, and
Blood. [Ik.
Contradion, Delation, Conception, Par-
co-motion, fition, Lrfcation.
Adion of Mi
nal objeds.
POWERS.
Senfibility and Vital refin¬
ance.
Irritability, Contrative power.
Vital refiftami
RELATIVE PREDO-
MINANCE.
Mofl: predominant in infan¬
cy ; female fex ; Tnelancho-
lic temperament; hypochon¬
driac, hysteric, and other
nervous affedions, and in
warm climates.
In manhood; huth; in thole of a fan-
fex ) the fanfmt temperament, and
rament, and fely imagination.
ous countries.
6. PRINCIPAL MORBID
AFFECTIONS.
Vertigo, Coma, Delirium,
Infanity.—Pain, Itching,
Want of feeling 5 Ageuf-
tia; Tinnitusaurium, Deaf-
nefs *, Intolerance of light,
Dyfopia; Caligo, Amau-
rojis.
Spafm, Convullyy'wwj-, Satyriajis, Nym-
ing, Paralysuomania, Menorrhagia,
menorrhcea, Impotence,
terility.
Chap.
Of Death.
*Recher-
ches, part ii
art. i.
476^
Progrtfs of
death com¬
mencing in
tire heart.
XVI. P H Y S I
It is to violent or accidental death that Bichat prin-
^ cipally confines his difcufiions, and in order to determine
with precifion the phenomena that take place in the three
fpecies, he examines at great length, the relations that
fubfift among the three functions of' circulation, refpira-
tion and feniation, as they are affected byj.he death of
the heart, the lungs, or the brain. He firit confiders*
thofe cafes of iudden death that commence with the
death of the heart } then thofe originating in the lungs ;
and laltly thofe originating in the brain. He thows
how, one of thefe functions ceafing, the others fuccef-
fively flop; he points out the mechanifm by which the
death of all the parts follows that of the organ firff: af¬
fected } and he determines, according to his own prin¬
ciples, the nature of the feveral difeafes by which the life
of the heart, the lungs, or the brain, is exlinguifh-
ed *.
We confider this as the molt interefting part of his
valuable w'ork, and it well deferves the attentive peru-
fal of every medical man. We regret that we cannot
do more than extract from it the view given by the au¬
thor of the fucceffive phenomena produced by the in¬
fluence which the death of each of the vital organs ex¬
erts on the general death of the hotly.
Whenever the heart ceafes to aft, fays Bichat, gene¬
ral death comes l in the following manner. The ac¬
tion of the brain ceafes for wrant of excitation •, and from
the fame defeft, the fenfation, locomotion and fpeech,
which immediately depend on the general fenforium, are
interrupted. Befides, for want of the excitation of part
of the blood, the organs of thefe funftions would ceafe
to aft, even though the brain were fuppofed capable of
exerting on them its ufual influence. The whole of
the animal life, then, is fuddenly arrefled. The man,
from the moment that his heart dies, ceafes to exift with
refpeft to furrounding objefts.
The interruption of organic life, which has commen¬
ced through the circulation, operates at the fame lime
through the refpiration. The mechanical aftions of the
lungs no longer proceed when the brain ceafes to aft,-
fince on this organ depends the aftion of the diaphragm
and intercoftal mufcles. The chemical changes can no
longer take place, when the heart can neither receive
nor convey the materials neceflary for their developement.
InTnort, general death continues to proceed in a gradual
manner, by the interruption oi Jecretion, exhalation, and
nutrition. Thefe are the effefts produced when death
is the confequence of a wound of the heart or large
blood-veflels, a rupture of the heart, or fimilar accidents f.
Proorefs of The feries of phenomena that take place in death, as
death com- commencing in the lungs, is different according as the
mencing in mechanical or the chemical aftion of thefe organs is firft
arrefled. I. In the former cafe, as when death is pro¬
duced by an extenfive wound or laceration of the dia¬
phragm, by the frafture of a great many ribs at the
fame time, &c. they proceed as follows: 1. Ceffation
of the mechanical aftion ; 2. Cefiation of the chemical
phenomena, for want of the air which lupported them j
f 7,’. art. 5.
the lungs.
O L O G Y. 525
3. Ceflation of the brain’s aftion for want of the red blood Of Death,
by which it wras excited 5 4. Interruption of animal life, 1
of fenfation, locomotion, and fpeech, from the lofs of the
exciting powers of the brain and the red blood on the
organs of thofe funftions \ 5. Stoppage of the general-
circulation ; 6. Stoppage of the circulation in the capil¬
laries, of fecretion, abfbrption, exhalation, for want of
the excitation exerted on their organs by the red blood y
7. Ceflation of digeffion, for want of fecretion, and
of excitation of the digeftive organs. II. When the
chemical aftion of the lungs is interrupted, as when an
animal is confined in a vacuum ; in cafes of Jlrangula-
tion, fuffocation, drowning, &c. the phenomena of death
proceed in the following order: 1. Interruption of the
chemical phenomena ; 2. Confequent fufpenfion of aftion
in the brain ; 3. Ceflation of fenfation, voluntary mo¬
tion, voice, and the mechanical funftions of refpiration ;
4. Stoppage of the heart’s aftion, and of the general
circulation 5 5. Termination of the capillary circulation,
of fecretion, exhalation, abforption, and, by confequence,
of digeftion ; 6. Ceflation of animal heat, which, be¬
ing the refult of all the funftions, muft ceafe when all. r,
thefe are terminated J. 9*
The phenomena of general death commencing in the Prog refs of
brain come on in the following feries : 1. Ceffation oThath com-
the brain’s aftion j 2. Sudden interruption of fenfation r^fncmS l'1
and voluntary motion •, 3. Simultaneous paralyfis of the
diaphragm, and intercoftal mufcles; 4. Interruption of
the mechanical phenomena of refpiration, and, by con¬
fequence of voice •, 5. Ceffation of the chemical pheno¬
mena 6. Paffage of the black blood into the fyftem of
red blood \ 7. Impeded circulation, from the aftion of
the black blood on the heart and arteries, and from the
immobility of all the parts, efpecially the organs of the
cheft ; 8. Death of the heart, and iloppage of the ge¬
neral circulation ; 9. Simultaneous interruption of orga¬
nic life, efpecially in the parts that are ufually penetrat- 57,; aJ.t I7
ed by red blood ; 10. Abolition of animal heat
We have now gone through the feries of phyfiologi- ConciufioH.
cal enquiries, into which we propofed to enter in this
article. In forming an eftimate of the merit due to our
labours, we requelt that our readers will confider tire
article as in a great meafure fupplemental to many that
have preceded it in the courfe of the prelent work. It
has been our principal objeft to fill up blanks and fup-
ply deficiencies, efpecially with refpeft to Comparative
PhyJiologij; and to form, with thofe preceding articles
which have a reference to the animal economy, particu¬
larly Anatomy, Medicine, Midwifery, Chemis¬
try, Man, one conncBed, \i not uniform whole. The
difficulty of the talk vee had undertaken will probably
be admitted as-fome apology for the imperfeft execution
of it ; while the variety and interefting nature of the
fubjefts which we have treated, with the numerous re¬
ferences to the moft refpeftable fources of information,
will, we truft, render this article acceptable both to thev
general and- the fcientific reader.
EXPLANATION of PLATE CCCCXVIII.
Fig. 1. Exhibits a view of the exit from the head,
and dijlribution in the chejl, of the great fympathetic nerve,
intended to illujlrate the mutual relations between the
lead and the principal organs of the chejl and belly.
A. The right parotid gland laid bare.
B. The fuhmaxillary gland.
C. D, E. The digajiric mufcle, partly covered by
the fubmaxillary gland.'
Fi
526'
PHYSIOLOGY.
T. Part ef the thyroid gland.
G, G. The afophagus or gullet.
H, H. The wind-pipe or trachea.
II, III. IV. V. VI. VII. The bodies of the fix lower
vertebrce of the neck ; VIII. IX. the two firft vertebrae
of the back.
I, K, L. The heart, with part of the pericardium at¬
tached.
p, p. The arch of the aorta, drawn afide.
q. The common trunk of the right fubclavian (»)
ind right carotid (v) arteries.
P. The vena cava from the fuperior parts j £). That
from below.
R, S, T. The right lobe of the lungs.
U, V. Part of the left lobo,
W, X, Z. Mufcular parts of the diaphragm.
a. The firft cervical or great ganglion, from which
proceed, h. The trunk of the great fympathetic nerve,
and c. The eighth pair of nerves, or par vagurn.
d. The lower cervical ganglion, cppofite the fifth
cervical vertebra.
e. The upper thoracic ganglion, oppofite the firft
vertebra of the back.
f. The third dorfal ganglion, between the fecond and
third rib.
g. The acceffbry nerve of Willis.
h. i, k, l. Trunks of feme of the cervical nerves.
m. The cardiac plexus formed by branches from the
fympathetic nerve.
n, n. The par vagum tunning down to the diaphrngfn,
through which it paffes, unites with the intercojlal,
forms various ganglia, and gives branches to moft of the
abdominal vifeera.
o, o. The phrenic nerves diftributed to the dia¬
phragm.
Fig. 2. A feftion of the cuticle of the hlium chalce-
donicum, to (hew the lymphatic vej/els, much magnified.
Fig. 3. A fimilar magnified view in the onion.
Fig. 4. Ditto in the pink.
Fig. 5. Reprefents the atlantal extremity of the flow
lemur (lemur tardigradus), to (how the curious divi-
fion of the fubclavian artery.
a. The fubclavian artery, lying upon the fubfeapu-
laris mufcle.
b. The divifion of the artery into equal-fized cylin*
ders.
c. The ulnar artery proceeding to divide in the ufual
manner.
Fig. 6. Reprefents the facral extremities of the fame
animal, fhowing a fimilar divifion of the inguinal ar¬
tery.
a. The diaphragm.
b. The defeending aorta.
c. c. The iliac arteries.
d. The trunk of the inguinal artery, fituated umoing
the cylinders.
e. The femoral artery under fimilar circumftances.
The annexed Table fufticiently explains itfelf.
ERRATA.
Page 501. col. 2.' line 23. from the [top, for the circulation, read, the lefler circulation. N°. 360. for chryfolites,
read, chryfalids.
I N D E X.
ylBSO R BENT fyftem, difeovery of, Xf'4 x
Abforption, 26, 184
organs of, 185
by lafteals, &.c. 186
by the veins, 187
by the Ikin, 188
of the loweft Gaffes of ani¬
mals, 190
of the ants, 191
theory of, 192
relations of, 203
Accidental colours, principal phenome¬
na of, 100
Ajr, quantity of, received and emitted
during refpiration, 223
afeertained changes on, 226
volume of, fenfibly diminiftied, 227
changes on, by the refpiration
of inferior animals, 23 2
by vegetation, 233
Alnficori's opinions refpefling man, 29
Anatomy, relation of, to phyfiology, 6
Anaxagoras's phyfiological opinions, 30
Amimdon, fu{pended, of feme animals, 363
Appetite for food, N°i 50
Ari/lotle's phyfiological opinions, 34
Arrangements in phyfiology, 17—22
remarks on, 24
Arteries, aftion of, 20 2
diftribution of, in the limbs of
flow-moving animals, 214
AJJimilation a chemical procefs, 262
power of, limited, 264
Azote, doubts refpeGingits lofs by re¬
fpiration, 23 I
B.
Barclay's ideas of vitality, 73
principles of mufcular mo¬
tion, 130
Bats fuppofed to poffefs a fixth fenfe, 104
Bichat's phyfiological arrangement, 21, 49
divifion of life, 49
obfervations on death, 375
Bile, ufes of, 273
Blood, how afted on by the veffels, 217
changes on by refpiration, 235
Boerhaave's fyftem, 42
Bflock's explanation of the modem
theory of refpiration, 238
Bofock's defence of ditto, N°240
objections to Mr Ellis’s opinions, 242
C.
Carbonic acid gas generated during
refpiration, 229
Cellular membrane, action of, 271
Chemifls, phyfiology of, 37
Chemifry, relation of, to phyfiology, 7
Chyle, properties of, 178
firft formed in the pyloric por¬
tion of the ftomach, 163
Clylifcation explained, 177
Chymif cation, exp]ained, 159
Circulation, ch. vii. 26, N° 59
difeovery of, 40
organs of, 193
proofs of, 197
in the human adult, 198
in the human fetus, 199
how ctrried on, 200
of the inferior animals, 205
of the mollufca, 206
in the vermes, 207
in cruftacea, 208
none in plants, 210
CirtuUtioq
3
Index.
Circulation, »one in feme animals, N° 2il
relations of, with fenfation, 212
with motion, 213
digeftion, 215
ablorption, 2x6
Climbing, nature and mechanifm of,
explained, 142
Cullen's phyfiological fyftem, 47
Cuvier's arrangement, 20
idea of life, 70
D.
Darwin's fyftem, 48
hypothecs of the retrograde
aftion of lymphatics, 189
Death, ch. xvi.
natural, gradual approach of, 367
violent or accidental, 368
figns of, 369
enterions of, 370
caufes of, 372
nature of, 374
Deglutition explained, 157
Democritus, opinions of, 31
Des Cartes's phyfiological opinions, 39
Dig e/Hon, ch, v. N° 26, 58
differences of, 154
fteps of, 155—160
various theories of, 172
relations between it and fen¬
fation, 181
relations of, with motion, 182
morbid affe&ions of, 183
Di/lenjion an exciting caufe of irritabi-
lity, 119
Dreaming, 352
Dumas's arrangement, 19
opinion of the ufes of the
fpleen, 275
E.
F.gg, progreffive changes of, during in¬
cubation, 326
Ellis's objections to the modern theory
of refpiration, 239
opinion refpefting refpiration, 241
defence of ditto, 243
Empedocles, opinions of, 30
Excretion, ch. xi. N° 26
organs of, 281
by the inteftines, 282
by the kidneys, 284
by the fkin, 286
Experiment, a mean of improving
phyfiology, 16
iEyes of cruftacea and inffcCts deferibed, 98
Fecundation, 313
Fecundity ef animals, comparative,
Note (l) 324
Feeling. See Touch.
univerfality of, 81
Fermentation not the caufe of digef¬
tion, 173
Ferriar's arguments againfl the vital
principle, 71
PHYSIOLOGY.
Flying explained, N° 143
Food firft diffolved in the cardiac por¬
tion of the ftomach, 164
comparative folubility of, 17I
paffage of, through the inteftines, 180
Funciions of living beings, 37
G.
Galen's phyfiological opinions, 36
Galloping explained, 141
Galvanifm an exciting caufe of irrita¬
bility, 11 §
juice, aClion of, 173
Generation 311
effence of, 313
gemmiparous, 314
oviparous, 321
viviparous, 3 23
theories of, 336
relations of, 343
Girtanner's hypothefis refpeCling irri¬
tability, 126
Goodivin's opinions refpeCling life, 67
Gough's explanation of ventriloquifm, 252
H.
Haller, opinions and difeoveries of, 46
opinion of the caufe of irritabi¬
lity, _ 123
Harvey's merits difeuffed, 40
Hearing, fenfe of, 93
organs of, 94
comparative phyfiology of, 96
Heart, aClion of, 201
Heat not the foie caufe of digeftion, 173
animal, 246
Herophilus, opinions of, 3 3
Hibernation of mammalia, 336
of birds, 337
■ of reptiles, 338
of fiflies, 339
of infeCls, 360
of man, 361
of plants, 364
phenomena of, 362
Hippocrates, phyfiology of, 32
Hoffman's phyfiological opinions, 44
Home's difeoveries refpeCling the aClion
of the ftomach, 161
experiments on the ufe of the
fpleen, 276
Hufeland's idea of life, 68
HumboldCs idea of life, 69
hypothefis refpefting irri¬
tability, 127
Hunter's, John, opinions ©n the life of
the blood, 66
I.
Impregnation, mode of, '318
Infalivation explained, 13
InfeBs, want of circulation in,
how fupplied, 209
Integumation, ch. xii, N? 26
vdcs of, as defence, 290
527
Integuments ufeful by their hardnefs, N°29i
by their external
covering, 292
by their effluvia, 293
by their colour, 294
change of 295
Irritability, ch. iii. N° 26
general phenomena of, I ri
definition of, 112
different acceptation of the
term, 113
flimuli exciting, 114
caufes of, opinions refpe£ling, 1 21
chemical do&rines of, 125
laws of, 128
K.
Kidneys, action of, 284
Leaping, nature and mechanifm of, ex¬
plained, 138
Life, general idea of, 26, 51
effects of, 33
caufe of, 64
duration of; 63-
comparative pertinacity of, 371
Light, effect of, on the lyftem, J02
abfence of, fuppofed to favour
obefity, 103
Liver, aftion of, 272
Locomotion^ ufes of, 148
Lymphatics, retrograde aftion of, 189
M.
Mafication explained, 133
Mechanics, opinions of, 43
Motion, ch. iv. N° 26, 37 •
organs of, 129
principles of, 130
progreffive, of animals, 131
relations of, with fenfation, 149
vegetable, 147
Mufcles, motion of, affifts circulation, 204
N.
Nervous fyftem, ^5
ftuid, theory of, no
energy and exciting caufe of
irritability, ng
Nicholfen's account of a ventriloquift, 231
Nutrition, ch. ix. N° 26
nature of, 260
not performed by nerves, 263
of infe&s and zoophytes, 264
°.
Obfervation a mean of improving phy-
fiology, 14
Odours, nature of, little underftood, 91
Organized beings compared with in¬
organic matter, 3^
Orniihorinchus, the connecting link
between quadrupeds
and birds, 168~
Oxygen of the air diminifhed during
refpjration, 228
R.
528
p.
PaJJions, violent, exciting caufes of ir¬
ritability, N° 120
Perfpiration, quantity of, 287
compofition of, 288
relations of, 289
Physiologij, definition and objeft of, 1
divifions of, 2
hiftorical, 3
philofophical, 4
praftical, 5
relations of, to anatomy, 6
to chemiftry, 7
to mechanical philofophy, 8
to metaphyfics, 9
to natural hiftory, 10
importance and utility of, 11
methods of fludying, 12
means of improving, 13—16
application of, to zoology, 23
tabular outline of, 26
hiftory of, its utility, 27
Plato's phyfiological opinions, 33
Pultnonic organs of circulation, 196
Putridity not the caufe of digeftion, 176
Pythagoras'1 s opinions refpefting man, 28
R.
Relations of fenfation, 149, 181, 212, 257
of motion, 149, 182, 213,258,
283
of digeftion, 181, 215, 259, 277,
283
of abforption, 193, 216
of circulation, 212, 256
ef refpiration, 255
of inteftinal excretion, 283
of urinary excretion, 285
of perfpiration, 289
Reproduciion, ch. xiv. N° 26, 61
of parts in man and mam¬
malia, 304
in reptiles, 306
in cruftacea, 307
in mollufca, 308
in polypes, 309
writers on, 310
Rejijlance to chemical change, a pro¬
minent effe£t of life, 54
Rxfpiration, ch. viii. N° 26, 60
neceflity of, 218
organs of, 219
mechanifm of, in man, 221
in other ani¬
mals, 222
experimental writers on, 225
effefts of, on the animal
fyftem, 234
theory of, 237
ftill incomplete, 244
ufes of, 245
relation of, with circulation, 158
PHYSIOLOGY,
Refpiration, relations of, with fenfation,
N° 257
motion, 258
cflgeftion, 259
Refpirations-, ordinary number of in a
minute, 224
Reverie, 354
Richerand'>stxf?ir\?L\A(m of ventriloqulfm, 2 5 2
Rumination explained, 158
in man, cafes of, Note G,'
D , Pa§e 49°-
Running explained, 139
RuJIPs ideas of vitality, 7 2
Index.
T.
Secretion,
S.
ch. x'. N° 26
organs of, 267
kinds of, 268
matters furniftied by, 269
modifications of, 270
Secretions, peculiar animal, 278
vegetable, 280
Senfation, ch. ii. N° 26, 62
organs of, 76
laws of, 105
comparative phyfiology of, 107
theory of, 108
relations of, 149, 181, 212
Senfbility, neceflity of, to organized
beings, 74
of the animal body, 8 2
Senftivity, 75
Sight, fenfe of, 97
organs of, 98
Sleep, neceflity of, 344
phenomena of, 346
theory of, 347
of plants, 351
Sleep-walking, 3 ^3
Smelling, fenfe of, 89
Organs of, 90
theory of, 91
comparative phyfiology of, 92
Snails, copulation of, 319
Somnambulifm, 353
Sound, varieties of, 95
Speech, mechanifm of, 250
Spleen, ufes of, 274
carries off fluid from the
ftomach, 277
Stahl'1 s fyftem, 45
Standing on two feet explained, 133
on four feet, 134
Stomach, organic action of, 160
human, the link between
carnivorous jand phytivor-
ous ftomachs, 162
divided into a cardiac and
pyloric portion, 163
curvature of, accounted for, 167
Swimming explained, 144
Syflemic organs of circulation, 196
Tqjling, fenfe of, N° 83
organs of, 84
varioufly affected, 8 5
perfe&ion of, gg
modifications of, 8 7
ufes of, 88
Temperature, animal, 236
equable, prefervation of, 247
Torpor of animals, 355
theory of, 36 r
Touch, fenfe of, <77
ufe of, 7 g
organs of, 79
nature of, 8&
Transformation, ch. xiii. N° 26
of reptiles, 297
of infects, 298
accompanied by change
of propenfities, 300
confifts in the evolu¬
tion of parts, 301
Trituration not the foie caufe of di¬
geftion, 174
Trotting explained, 140
'V.
Van HelmonRs phyfiological opinions, 38
Veins, valvular ftru£ture of, aflifts cir¬
culation, 203
Ventriloquifm, account of, 251
how explained, 252
Vibration, a theory of fenfation, 109
Vis infta, of Haller, 123
Vifion, immediate feat of, probably the
retina,
phenomena of, 100
diftinft, requisites for, 101
Vital principle, opinions refpe£ting, 65—-73
exiftence of, denied by
fome, 70, 71
fuppofed to be divifible, 73
Vitality, degrees of, 55
Voice peculiar to thofe animals that
have lungs, 248
human, amazing variety of, 249
mechanifm of, 250
of brutes, 2? 3
of birds, _ 254
Volition, an exciting caufe of irritabi-
%> 115
W‘
Walking on two feet explained, 136
four feet, 137
Whiff's arguments in fupport of ner¬
vous influence, as exciting
irritability, 122
z.
Zoological arrangement of phyfiology, 22
PPIYTOLACCA*
PHYSIOLOGY
Plate CCCCXV1U
Pj: ano Forte Key
Bs// ■ ‘'Im BBT:/cutyifer^/fcit
k
P I A [52
Phytolacca PHYTOLACCA, Pokeweed, or American Night-
!1 fhade, a genus of plants belonging to the decandria clafs.
.p,acen2a;; See Botany Index.
PHYTOLOGY, a dlfcoutfe concerning the growth,
kind, and virtues of plants. See Botany, and Mate¬
ria Medica.
PHYTON, a general of the people of Rhegium againft
Dionyfius, the tyrant of Sicily. He was taken by the
enemy, and tortured, and his Ion was thrown into the
fea. See Syracuse.
PIA mater, a thin membrane which covers the brain
and is in immediate contact with it. See Anatomy Index.
PI ABA, in Ichthyology, is a fmall freih-water fifh
caught in all the rivers and brooks in the Brafils, and
in lome other parts in America. It is about the iize of
the common minow.
PIABUCU, in Ichthyology, is an American fifh, eaten
in many places by the natives. It is laid to be fo ravenous,
and greedy of blood, that if a perlbn go into the water
with a wound in any part of his body, the piabucu will
make up to it to fuck the blood. It leldom exceeds four
inches in length.
PIACENZA is a city of Italy, in the duchy of
Parma, in E. Long. 10. 25. N. Lat. 45. It is a large
handfome city, whole name is derived by fome from its
pleafant lituation, in a fruitful plain, on the Via ZEmi-
lia, about half a mile from the Po. It is the fee of a
biihop fuffragan of Bologna, and has a univerfity, but
of no great fame. It is defended by a wall and a
flrong citadel, and is reckoned about three miles in cir¬
cumference, fo that it is fomewhat bigger than Parma.
The houfes are low, but well built} the great llreet
called the Stradone is in a direft line and of equal
breadth, with a foot-way fenced with polls on each fide
like London, and is about 3000 feet long. The houfes
are generally built of brick, and fome of them are pret¬
tily painted. The cathedral is an old ftrudlure, but
'veil adorned within. The duke of Parma, who is fo-
vereign of Piacenza, has a palace in the city built by
Vignola. There are many excellent paintings in this place.
There are two chapels painted, one with the hiftory of
St Catharine, and the other with a picture of Chrift, as
alfo the altar of the church of St Auguftin, all by Por-
denone. In the fame church there is a fine pidlure of
the bleflfed virgin, St Peter, and St Paul, by Paolo Ve-
ronefe. At the Capuchins there is'a Francis by Guer-
cmo. There is a fountain faid to have been erefted
here by Julius Crefar, and the equeftrian ftatues of the
famous general iMexander I. duke of Parma and Pla¬
centia, and of his fon Ranuccio, both in the great
fquare. In the palace of Scotti, there are a great many
fine pictures by Lanfranco, who had been a page in
their family, and among the reft the rape of Helen, the
taking of Troy, the blefled virgin, and St Francis. The
trade of this city confifts chiefly in their cheefe, as at
Parma, thefe cities being furrounded with the richeft
pafture grounds in Italy; though the greateft part of
what is called Parmefan cheefe is made in the duchy
of Milan, and particularly at Lodi. See Parmefan
CHEESE.—Without the walls, which are wallied by the
ru ers drebbia and Po, there is a large feminary or
college, magnificently eredled by Cardinal Alberoni, a
native of this city, but confiderably hurt by the modern
Goths in the laft war. Towards the north of the citv
Vol. XVI. Part II.
9 ] PIA'
is the mouth of the river Trebbia, famous for the vitlory Piano Forte,
which Hannibal obtained over the Romans. * J
PIANO Forte, or Forte Piano, is a mufical in-
ftrument, which is too well known to require any de¬
tailed defeription. We fliall here, however, notice
fome of its peculiarities. The voice, it has been ob-
ferved, is the original mufical inftrument) of this all
other inftruments are to be confidered but as imitations j
and it is remarkable with what promptitude, as well as
accuracy, the voice of man obeys the impulfe of the
heart. Even a coarfe ear is hurt by an error in its
tone, amounting to what is called a comtna ; and a li¬
mited voice can execute melodies which include 12
notes, or an oftave and a fifth. Between thefe extremes
the motion of the glottis does not amount to one-twelfth
of an inch, which mult therefore be divided by the moll
ordinary finger into more than 1000 parts. All this
too, without any feeming effort of thought, is done in
an inflant, and repeated with rapidity, without miftak-
ing one of the divifions.
The great objedl in the conftruftion of mufical in¬
ftruments is, to bring them as near as pofilble to exprefs
the founds produced by the human voice: the violin,
however, and a few of the Ample wind inftruments, are
the only ones found fully to exprefs thefe momentary
gradations of fentiment, and thofe tender and delicate
emotions with which the heart is agitated. For the *
purpofe of removing this defetft of harmonic inftruments,
the fwell was added to the organ. Similar improve¬
ments were alfo attempted on other inftruments of the
fame kind, and in the fame way. The harpfichord was
ftmt up like the fwell organ, and was opened by means
of pedals, when the performer wilhed to- enforce the
found. But as this was found not to fucceed well,
other methods were tried, and in particular unifons
were added to each note, which were brought on, ei¬
ther by means of pedals, or by another fet of keys j
and in this way the power of the harpfichord was great¬
ly improved. Among all the keyed inftruments, the
Englilh piano forte feems to merit the preference, on
account of the fiiperior force of tone, adequate fweet-
nefs, and great variety of voice, of which, by the inge¬
nuity of Britifh artifts, it has now become fufceptible.
It has been called a national inftrument, becaufe it is
faid to be an Englifh contrivance, the invention of the
celebrated poet, Mafon. Mr Mafon had feen fome at¬
tempts that were made by the Germans to make keyed
dulcimers, which were in fome meafure fufceplible of
Cat forte and piano ; but as they were all conftrufted on
one principle, and required a particular touch of the
finger, which was of difficult acquifition, and which
fpoiled it for harpfichord praftice ; as they were alfo
deficient in delicacy and juftnefs •, and as the performer
was by no means certain of producing the very ftrength
of found intended, Mr Mafon removed all thofe imper¬
fections, by detaching the mallet entirely from the key,
and giving them only a momentary connexion. It is
by this improvement that the Englifh piano forte is di-
liinguiftied from all others. Mr Mafon’s general prin¬
ciple may be fully underftoed by the following defciip-
tion. In the figure on Plate CCCCXVIII. the parts
are reprefented in their ftate of inaftion. The key
ABK turns, as ufual, on the round edge of the bar B,
and a pm b, driven into the bar, keeps it in Us place.
3 X ‘ ‘ rI h e
P I A [ 530 ] P I A
Piano Forte. The dot F represents a feflion of the firing. ED is
* v   tiie mallet, having a hinge of vellum, by which it is at¬
tached to the upper Surface of the bar E. At the other
end is the head D, of wood, covered with Some Solds of
prepared leather. The mallet lies in the pofition repre¬
sented in the figure, its lower end relfing on a eullnon-
bar K, which lies horizontally under the v/hole row of
mallets. The key AR has a pin C, tipt with a bit of
the foftefl cork or buckfkin. This reaches to within
-~th of an inch of the fhank of the mallet, but muff not
touch it. The diifance Ee is about -yd or -Jlh of the
length of the fhank. When the end A of the key is
preiTed down on the fluffing (twro or three thickneffes
of the mofl elaftic wroollen lift) it raifes the mallet, by
means of the pin C, to the horizontal pofition E d, with¬
in -g-th or r~th of an inch of the wire F j but it cannot
be fo much preffed down as to make the mallet touch
the wire. At the fame time that the key raifes the
mallet by means of the pin C, it alfo lifts off the damper
G (a bit of fpunge) from the wire. This damper is
fixed on the end of a little wTooden pin G^, connected
with the lever g H, which has a vellum hinge at H.
This motion of the damper is caufed by the pin I, which
is fixed into the key near to R. Thefe pieces are fo ad-
jufled, that the firfl touch of the key lifts the damper,
and, immediately after, the pin C adds on the fhank of
* the mallet. As it adls fo near to its centre of motion,
it caufes the head D to move brifkly through a confider-
able arch D d. Being made extremely moveable, and
very light, it is thus tojfed beyond the horizontal pofi¬
tion E d, and it flrikes the wire F, which is now7 at li¬
berty to vibrate up and down, by the previous removal
of the damper G. Having m?de its ffroke, the mallet
falls down again, and reffs on the foft fubflnnce on the
pun C. It is of effential importance that this mallet be
extremely light. Were it heavy, it w7ould have fo
much force, after rebounding from the wire, that it
would rebound from the pin C, and again flrike the
\vire. For it will be recolledled, that the key is, at this
time, down, and the pin C raifed as high as poffible, fo
that there is very little room for this rebound. Leffen-
ing the momentum of the mallet by making it very
light, making the cufhion on the top of the pin C very
foft, and great precifion in the ffiape and figure of all
the parts, are the only fecurities againfl the difagreeable
rattling which thefe rebounds would occafion. In re-
fpedl to the folidity and precifion of workmanffiip, the
Britifh inflruments are unrivalled, and vafl numbers of
them have been fent to all parts of the continent.
As the blow of fo light a mallet cannot bring much
found from a wire, it has always been found neceffary
to have two firings for each note. Another circum-
. fiance contributes to enfeeble the found. The mecha-
nifm neceffary for producing it makes it almoft impoffible
to give any confiderable extent to the belly or found
board of the inftrument. There is feldom any more of
rit than what occupies the fpace between the tuning pins
and the bridge. This is the more to be regretted, be-
caufe the baffes are commonly covered firings, that they
may be of a moderate length. The bafs notes are alfo
of brafs, which has a confideralfiy lower tone than a
Reel wire of the fame diameter and tenfion. Yet even
this fubftitution for fteel in the bafs firings is not enough.
The highett of them are much too flack, and the low7eft
mull be loaded, to comgenfate foi want of length.
This greatly dlminiffies the fullnefs, and frill more the ^’rino Forte,,
mellownefs and difiindlnefs of the tone, and frequently Waflu*-
makes the very loweft notes hardly appreciable. This U",“v ‘
inequality of tone about the middle of the inftrument is
fomewhat diminiffied by conitructing the infirument
w ith two bridges j one for the fteel, and the other for
the brafs wires. But frill the bafs notes are very much
inferior to the treble.
PI AST US, a native of Poland, was originally a
wheelwright and the fon of Coffifco, a citizen of Cruf-
witz. He flourifiied in the year 830, when on the
extinction of the family of Popiel great difputes arofe
about his fucceffor, and Cracow7 was affiifted with a fe-
vere famine. During this extremity, when the people
were dropping dowm in the fireets, two angels in human Mzd. Uni<v.
forms, as the llory is told, took up their refidence withHijlory,
Piaftus, w7ho wTas celebrated for his piety and extenfive vo1'
charity. He had nothing left but a fmall cafk of the ^
common liquor of the country, and this he prefented to
his new7 guefts, who, charmed with his hofpitality,
promifed him the crown of Poland. The faith of Pia¬
ftus .was equal to his other virtues: he implicitly be¬
lieved the word of his guefts, and pioufty followed their
directions in every particular. He was ordered to dif-
tribute the liquor out of his little cafk to the multitude:
he did fo, and found that it was inexhauftible. The
people were afloniffied j all cried out, “ A miracle !”
and the electors determined to chufe a perlbn in whoie
favour Heaven had fo vifibiy declared : Piaftus was
accordingly taken from his fliop, and raifed to the ducal
dignity. _ # •
Such is the relation of the canon of Cracow7, w hich
differs in many particulars from the account given by
Guagnini, and feveral other hiftorians. According to
them, Piaftus had prepared a fmall collation, to enter¬
tain feme friends who were affembled at the birth of a
child. Two pilgrims, Paul and John, afterwards mur¬
dered at Rome, came about this time to Cracow7. They
begged charity at the door of the eleCtion-hall, and were
rudely repulfed 5 upon which they ftumbled on the houfe
of Piallus, and wrere kindly received. The miracle w7e
have mentioned was wrought by them ; and the two
pilgrims, and not angels, were the inftruments of the
elevation of the hofpitable wheelwright. Though we
pay but little regard to the marvellous means by which
Piaftus afeended the ducal throne of Poland, it would
be prefumptuous entirely to omit a fadt attefted by all
the waiters upon this fubjeft : it was proper, therefore,
to take notice of it, and w7e leave the reft to the reader’s
judgement.
Being now raifed to the fupreme dignity, he was not
intoxicated with his profperity. His natural charity,
benevolence, and fweetnefs of difpofition, remained:
nothing w as altered but his power of doing good. He
w7as truly called the father of his people : the injured
never returned unredreffed, nor merit unrewarded.
Piaftus wiped the tear from the eyes of the widow j
and w7as himfelf the guardian of the orphan, and the
general patron of the poor and diftreffed. His excel¬
lent inclinations ferved him in the room of great abi¬
lities $ and the happinefs that his people enjoyed made
them forget that their prince was not born a ftatefmen
and a w7arrior. Several inteftine commotions arofe du¬
ring his adminiftraticn, all which he quelled by the
niildncfs and clemency of Ills nature : his nobility were
affiamed
Pic [ s
Piaftus athamed of rebelling again ft a fovereign who devoted
.11 his whole life to render his people happy. He remo-
. Pica' , ved the court from Crufwitz, a city which he deteft-
ed, becaufe it was the fcene of Popiel’s crimes and tra¬
gical end, and fixed his refidence at Gnefna, where he
died beloved, efteemed, and even adored by his fubjefts.
It is in rgemory of this excellent prince, that all the
natives of Poland, who have been fince promoted to the
ducal or regal dignity, were called Piaftes, in contradi-
ftin&ion to the foreigners.
Piaftus affbciated his fon Ziemovitus with him in the
government before his death 5 a circumftance of much
benefit to the people.
PIAZZA, in Building, popularly called piache, an
Italian name for a portico, or covered walk, fupported
by arches.
The word literally fignifies a broad open place or
fquare $ whence it alfo became applied to the walks or
porticoes around them.
by PIBROCH, fays Dr Beattie *, is a fpecies of tune
2vo editfPecu^ar * think, to the Highlands and Weftern hies
p. 422. of Scotland. It is performed on a bagpipe, and differs
nute- totally from all other mufic. Its rythm is fo irregular,
and its notes, efpecially in the quick movement, fo mix¬
ed and huddled together, that a ftranger finds it almoft
impoflible to reconcile his ear to it, fo as to perceive
its modulation. Some of thefe pibrochs, being intend,
ed to reprefent a battle, begin with a grave motion re-
fembling a march, then gradually quicken into the on-
fet •, run off with noify confufion and turbulent rapidity,
to imitate the conflitt and purfuit ; then fwell into a
few flouriffies of triumphant joy ; and perhaps clofe with
the wild and flow wailings of a funeral proceflion.
PICA. See Corvus, Ornithology Index.
Pica Marina. See HiEMAToi-us, and Alca, Orni¬
thology Index.
Pica, in Medicine, a depravation of appetite, which
makes the patient long for what is unfit for food, or
incapable of nourifhing •, as chalk, allies, coals, plafter-
lime, &c. See Medicine Index.
Pica, or pye, had formerly the fame fenfe as ordi¬
nal, meaning a table or directory, pointing out the
order in which the devotional fervices appointed for
different occafions were to be performed. According¬
ly we are told it is derived from vi, a contradtion of
vnx^,, a table ; and by others from litera picata, a great
black letter at the beginning of fome new order in the
prayer. The term was ufed in a fimilar fenfe by offi¬
cers of civil courts, who called their kalendars or al¬
phabetical catalogues diredling to the names and things
contained in the rolls and records of their courts the
pyes.
Pica, orPicus,John, prince of Mirandola and Concordia,
was born in the year 1463, under the pontificate of Pius II.
He was the youngeft fon of John Francis of Mirandola,
and Julia, a lady of the noble family of Boiard. Some
of the credulous hiftorians of the time have related, that
at his birth a globe of fire was feen to reft upon his mo¬
ther’s bed, portending, fay they, by its fliape the per-
fedfion of his genius, and by its element, the celeftial
turn of his mind. As foon as he was capable of receiv¬
ing inftrudlion, he was placed by his mother’s care
under the moft able mafters, and very early diftinguifh-
e.d himfelf by the vigour of his application, and the
firength ot his memory } of which fuch prodigies are
1 ] .PIC
related as would be very difficult to credit, were we not p,c:i-
affured by fome modern inftances, of the perfedlion to
which that faculty may be carried. At the age of
fourteen he was fent by his mother’s direftion, who was
defirous that he fhould afiume the clerical fundtions, to
Bologna, at that time the principal refort of thole who
ftudied the pontifical law. After fpending two years
there, he became difgufted with this purfuit, although
fuch -was his induftry, even at that early age, that he com¬
piled an epitome of the pontifical epilties or decretals.
His difpofition, however, ftrongly led him to the purfuit
of philofophy, with an eager curiofity to penetrate the
fecrets of nature and fcience : with this view he travel¬
led over Italy and France, vinted the moft celebrated
fchools of each, and ftudied under the moft famous
teachers of both countries. After feven years fpent in
this courfe of inftrudlion, and at the age of twenty-
three, he went to Rome, and, after the falhion of the
fcholars of that time, brought himfelf into notice by
publicly propofing literary queftions for deputation.
This lort of challenge was very common in that age,
and, when printing was fcarcely pradlifed, and the name
of a man of learning lefs rapidly extended than it is
now, was almoft the only method that a perlbn of fu-
pjerior attainments had to make himfelf known. Pvli-
randola propofed 900 queftions, or as they were called
conclujiones, in dialedtics, mathematics, natural philofo¬
phy, and divinity, drawn not only from the ftores of the
Latin and Greek, but from the myfteries of the He¬
brew's and the arcana of the Chatdaeans and Arabians.
In addition to the endlefs topics of metapbyfics, theo¬
logy, and the ordinary fubjefts of difputation, into
which he entered very profoundly, the conclujioncs in¬
volved the ancient and obfeure philofophy of Pythago¬
ras, Trifmegiftus, and Orpheus *, the doftrines of the
Cabala, or myftic interpretation of the facred writings,
according to the Hebrew's, taught by Origen and Hi-
larius j the extent, ufes, and learning of natural magic,
which was vindicated from the vulgar reproach of im¬
piety and necromancy. Seventy-tw'o new phyfical and
metaphyfical dogmata of the author’s invention were
likew'ife propofed and defended. Thefe propofitions,
according to the oftentatious pratftice on thefe occafions,
W'ere fixed in the moft public places in Rome, and the
propofer engaged to defray the expences of any one
who fhould come from a diftance for the purpofe of dif-
puting w'ith him. This challenge did not bring for¬
ward any difputants, but expofed Mirandola to much
envy and jealoufy, particularly from the profeflbrs of
fcience at Rome, who felt the refle&ion that would be
call upon their credit by their declining a competition
w'hich they durft not encounter. Unable to injure his
fame as a fcholar, they made a much more dangerous at¬
tack upon the foundnefs of his faith 5 thirteen queftions
w'ere felecled, which were charged with the terrible
fufpiciort of herefy and conteriipt of the ordinances of
the church ; a fufpicion very readily liftened to by the
church when direfled againft great learning, which the
increafing influence of philofophy and letters began to
make her watch with extreme jealoufy. Mirandola re¬
pelled this attack by publifhing his Apologia, or De¬
fence of the accufed Propofitions; which if he did not
effefrually clear away the fufpicions he had incurred,
tended to confirm his enemies in their dread of his learn¬
ing and powers} and it muft be owned that, overlook-
3X2 ing ;
PIC [5
ing the mi'application of talents to Inch iubjefts, the
J Apologia exhibits a command of profound and well di-
gelled learning and keen argument, truly aftonifhing at
the age of twenty-three. This work, and the difcuf-
fions it contained of certain delicate points, added to
fome hints of the limit of pontifical controul in matters
of faith, were fo difagreeable to Pope Innocent VIII.
that he interdicted the reading both of the Apology and
the difputed queflions. The love of glory, however,
was not Mirandola’s only pailion : his youth, fplendid
accomplilhments, and the graces of his perfon, for which
he is faid to have been remarkable, attrafted the ad¬
miration and careffes of many diflinguifhed Roman
ladies, who united the love of letters to that of pleafure,
a tafte very common amongft the Italian ladies of that
age. The young philofopher yielded to the force of
thefe allurements, or rather, according to the account
of his nephew, and biographer, Francilco of Mirandola,
eagerly followed the bent of his difpofition, naturally in¬
clined to obey the. attractions of beauty.
But this life of pleafure, however fuitable to his con¬
dition and inclinations, was of a fhort continuance. Ir¬
ritated by the refllefs perfecutions of his enemies, and
obliged perpetually to defend himfelf againft the impu¬
tation of herefy, the moft formidable calumny which in
that age any man could have to contend with, he de¬
tached himfelf from vicious pleafures, and regulated his
manner of life by rigidly obferving the laws of abfti-
nence impofed by Chriftianity ; for being a’firm adher¬
ent to the Chriftian doctrines, the charge of infidelity
and the vigilance of his enemies made him the more fo-
licitous to guard againft the appearance of difobeying
them. Becoming from this time wholly devoted to
learning, he foon acquired fuch celebrity that the moft
eminent fcholars from all parts of Italy came to vifit
him for converfation or inftnnftion. As a proof of the
fincerily of his reformation, he committed to the flames
five books of elegiac poetry which he had compofed on
the fubjedt of his amours, together with numerous pieces
in Tufcan verfe, which had been addrefled to his various
miftrefles. There is perhaps reafon to lament that the zeal
of a new convert would not be fatisfied without this facri-
fice. It muft, however, be confidered that the fpiiit of re¬
ligion at that period exacted many facrifices from the pro-
feifors of Chriftianity, which the lenient temper of thefe
times does not call for. An example of this feverity is to
be met with amongft the works that ftill remain of Miran¬
dola ; at the end of which, in the folio edition publiftied
by his nephew, we find a learned and entertaining com¬
ment, in the Italian language, upon a compofition of his
friend Girolamo Benivieni, entitled XJna Carvzona de
Amorc fecundo la ?nente et opeuime dd Platonici, “A poeti¬
cal treatife upon love, explaining the dodlrines of the
Platonifts.” The author, Girolamo, informs the reader,
in a fhort preface, that he had determined to fupprefs
this poem and comme tt out of regard to his. friend’s
character and his own ; deeming it unbecoming a pro-
feffor of Chriftianity, in treating of celeftial and divine
love, “ to treat of it as a Piatonift and not as a Chrift-
ian 3” but that having lent it to fome of his friends for
their perufal, an imperleft and erroneous copy was
printed, which obliged him, but not till after the death
of Miranuola, to publilh it correftly j and he takes care
to allege, in excufe for himfelf, that he has apprized the
reader of his plan by the title of the. poem, and warned
32 ] p 1 c..
him in all places where Plato’s opinions depart from
thofe of Chrift, that the doctrines of a gentile and a
heathen are not entitled to the leaft weight compared
with the reafonings of the Chriftian theologifts, “ and
particularly the irrefragable arguments of the angelic
doftor St Thomas of Aquino.”
The firft fruit of Mirandola’s devotion to facred lite¬
rature was the Heptaplus, or Comment upon the Six
Days of the firft Chapter of Genefis, wTich was written,
in 1491. Two years afterwards he publiftied a treatife
in ten chapters, de Ente et Uno ; the objedl of which
was to reconcile the doftrines of Plato and Ariftotle,
and to demonftrate that the difputes of their refpe&ive
followers originated in a mifconception of the opinions
of thefe philofophers relative to the Ens and Unum, at
that time a fubjecl of mighty ftrife among the learned.
This treatife was held in high efteem by both fides. It
w'as the laft work of confequence that the author lived
to complete ; but he had laid the plan of a vaft and
comprehenfive work, which his early death prevented
the execution of. This was no lefs than to confound
the feven enemies of the Chriftian church, by examining
and refuting all their errors. In the profecution of this
defign, he had compofed and perfefled before his death
tivelve books againft aftrology, the mott popular and
the moft pernicious fuperftition which then infefted the
world. Paulus Jovius, biftiop of Nocera, has left a
teftimony to the merits of this work, w hich is above all
other encomiums:—“ In this excellent though unfinifti-
ed work, Mirandola attacked the aftrologers with fuch
erudition and keennefs, and fo ably expofed the abfurdi-
ty and vanity of the 4whole art of divination, that he
feems to have deterred the profeftbrs of the occult
fciences fiom writing*.” ' _
This great defign, as well as many others which Mi- 'dq^ (/yT
randola had formed, particularly that of a more com-p. pj.
plete efTay towards reconciling the opinions of Plato and
Ariftotle, was fruftrated by his death. From the time
that he left Rome, which ivas foon after the publica¬
tion of the Apologia, Mirandola generally reftded ei¬
ther at Ferrara or at Florence. The friendftiip of the
prince of Ferrara and its vicinity to his paternal feat
attracted him to the former place ; but Florence was
the moft agreeable to him, on account of the fociety of
literary men which it afforded, and particularly of Po/i-
tian and Lor01-7,0 de Medici, with whom he entertained
a clofe friendfhip, Befides thefe two illuftrious men, his
fociety was cultivated by other eminent fcholars, among
whom was the learned and unfortunate Hieronymus Sa-
vanarola, and Hermolaus Barbarus: Petrus Crinitus,
the pupil of Politian f, mentions him as excelling all his } p. Cn’ni-
companions in the erudition and eloquence of his con- tus de ho-
verfation. The fame author has left us an account °f reJtaDifcip.
Pica’s laborious ftudies; for when Politian had expreffed |jb’Vi'c ’(>*
in his prefence high admiration of his great genius and & Kb. K.
learning, Mirandola with lingular modefty anfwered, c. 2.
that he deferved no praife but for his aftiduous applica¬
tion—Gratulandum potius, intelligite, affiduis vigiliis
atque lucubrationibus, quam noftro ingenio plauden-
dum I lb. fib. ii.
His library like wife is celebrated by the fame writer,c- 2.
and is faid byFrancifco de Mirandola to have coft 7000
pieces of gold. His accomplilhments were not confined
to fubjedls of abftrufe literature ; in his youth he was
much attached to mufic, in which he acquired fuch Ikill,
that
* Paul.
P 1 c [53
that fome of his melodies were publicly received, and
held in great eileem. It might alfo be concluded, from
an anecdote related by Petrus Crinitus, that he was not
unacquainted with phyfic 5 for according to that author,
when Hermolaus Earbarus was feized at Rome with a
dangerous fever, Mirandola fent him from Florence a
medicine prepared by himfelf. No man ever teftified a
more fmcere devotion for learning and philofophy, to
the contempt of all other qualifications, than the Prince
of Mirandola. He poflelfed a very large eftate, which
he bellowed almoft entirely upon works of charity, ex¬
cept what was fpent in collefting books, and entertain¬
ing and providing for literary men. At length, howT-
ever, about three years before his death, he made over
te his nephew Francifco his principality and pofleffions
in Mirandola, and obtained a confirmation of the grant
from Maximilian, the Roman emperor, to whom that
principality was fubjeft. He referved to himfelf only
enough to purchafe a fmall eftate near Ferrara, where
he fpent the remainder of his life, except wdien he re-
fided at Florence, in elegant and learned retirement.
His mother, under whole care he received his education,
had deftined him for the church ", and he was often
urged by his friends to embrace the facred profeffion,
with the certainty of the higheft honours and emolu¬
ments : but nothing could induce him to quit the life
that he had chofen. He died of a fever at Florence, in
the year 1494, in the 31ft year of his age, on the fame
day that Charles IX. of France entered that 'city
on his famous expedition into Italy. That monarch,
hearing of Mirandola’s illnefs, as he approached the
city, fent two of his own phyficians to his afiiftance ",
but in fpite of their aid, the violence of his diforder put
an end to his exiftence in 13 days.
With relpedt to the works of this author, fomething
has already been faid, and little more remains to be ob-
ierved. The Conclujiones afford a very complete fpeci-
men of the learning of the age, and of what were deem¬
ed the mold valuable purpofes to which learning could
be applied. However ufelefs and unprofitable thefe pur¬
pofes may appear to us, it will not be denied by any
one, who has the curiofity to look through the Conclu-
fwnes, that the mafs of learning, which muff have been
poffeffed by the propofer of them, is prodigious 5 when
it is recolledled that, at the time he propofed them, he
w as no more than 23 years of age. For there is not the
leaft reafon to fuppofe, that a perfon whofe works prove
him to have been a man of profound learning, and wdro,
in an age and nation diftinguifhed by fome of the bright-
eft fcholars that ever appeared, was ranked by their own
judgement amongft the firft, fhould have challenged the
difcuftion of any of the propofed fubjedls, without being
w'ell provided with the knowledge necefiary for fuch a
debate. The manner in which the queftions were pro¬
pounded leave little room to doubt that the author was
deeply verfed in the refpedHve fubjefts of them ; and
the Apology for the accufed propofitions, particularly
thofe de Salute Origenis and de Magid atque Cahald, dif-
cover familiarity with the waitings of the Fathers, as
3 ] PIC
w'ell as with the Greek and Hebrew claffics, and a fad- Po¬
lity of language and argument that could not be acquired 1 " ~v
at that age without extraordinary powers of mind. It
would be worth while to tranfcribe the whole of this cu¬
rious piece for the amufement of fuch of our readers as
may not have accefs to the original, but our limits do
not admit of it.
It is curious to obferve how greatly the hidden growth
of learning outftripped that of iblid icience. No age,
perhaps, was ever lb remarkable for the learning w hich
it produced as the period from the middle of the 15th
century to the beginning of the 16th j yet, except the
ineftimable obligations we owe to the learned men of
that time for their editions of the claflics, later ages have
been little benefited by their wmrks, which are either
loft or neglebted, and even the fciences they treated of
exploded and ridiculed. School-divinity and metaphy-
fics, though the moft attended to, were not the only
ftudies in wdrich the vaft erudition of that age was
willed. The myfterious doffrines of the Cabala formed
a favourite ftudy of fome of the moft learned fcholars.
The propofition wdiich laid Pica open to the indignation
of the church, was that in which he aflerted the ortho¬
doxy of Origen •, for Origen, notwdthftanding his meri¬
torious labours in the caufe of Chriftianity, his daring
zeal and felf-martyrdom, and notwithftanding the de¬
fence of Eufebius, wTas configned by the fentence of the
church to inevitable damnation, on account of his error?
in the myfteries of the faith. To queftion his perdition,
therefore, w7as to deny that the church wTas the interpre¬
ter of the divine intentions. The defence of this part of
the Conclujiones is wudtten with a boldnefs that could
hardly be expected from an Italian of the 15th century.
But the hardieft of thefe propofitions was that in which
it is aflerted, that faith is not in a man’s own power.
In defending this and the other propofitions, wdrich were
taxed with herefy, Pica probably relied lefs on the fpi-
rit and ability of his juftification, than on his owrn high
rank and ftation, together wdth the countenance and
proteftion of his powerful friends, particularly the Me¬
dici, whofe liberality of fentiment in regard to religious
points wTas fo notorious, that even Leo X. has been di-
reftly charged, not only with herefy, but infidelity *. * Milner's
By the Cabala, a term at this time generally mifap-
prehended, w7as underftood fometimes a fpecies of divine vop ;v’’
magic operating by the agency of good fpirits, as magic
commonly fo called was fuppofed to do by that of evil
beings ", but the true definition of it, as received by the
beft of its profeflbrs, is given by Reuchlinus (a), in his
treatife addrefied to Lorenzo de Medici, Divines Revela-
tionis adfalutiferam Dei et formarum feparatarum con-
ternplationem traditee fymbolica receptio,—a fymbolic ac¬
ceptation of the Mofaic hiftory (for that is meant by di-
vina revelatio') which produced a pure and perfect ac¬
quaintance with the nature of the divinity and of fpirits;
and according to the opinions of fome, which feem to be
revived by the modern Swedenborgians, this knowledge,
rvhen fublimed to the higheft perwdfion it was capable
of, and accompanied with perfect purity, was believed
to -•
(a) this treatife, which contains the whole learning upon a fubjefl once held in the higheft veneration by men
of learning, is very curious, and is to be found in the folio edition of Mirandola’s works,, publilhed at Bali I,
in J 557-
Firn.
■nus de Arte
■Cabalijl.
F 1 c r 534
to raife the mind to an abfolute familiarity with good
angels, by whofe affiftance the poffeffors of the cabalic
fecrets were enabled to do miraculous things. This art
was derived from the rabbinical doctors, who were at
firft called Thalmudiits j and, about the middle of the
f Reuchli-^ jjth century, according to Pica de Mirandola f, its
profeffors were denominated Cabalici, Cabalmi, or Ca-
balillae, according to their different degrees of perfec¬
tion : they afterwards, however, departed from their
mailers the Thalmudiits j the latter, according to Reuch-
linus, being chiefly intent upon the law and the expla-
mation of it, while the former, paying lefs regard to
•what concerned human affairs, aimed chiefly at elevation
of mind and thought. The ideas and dodtrines of the
Cabalifts feem to have been well known to Milton, and
perhaps fuggefled fome palfages in Paradife Loft. In
Reuchlinus’s Expofltion of their myfteries there is a cu¬
rious paffage deferibing the fpeech of the Deity to the
heavenly fpirits after the fall of Adam, with the future
profpedt of redemption by the incarnation of the Mef-
uah, whom the Cabalifts recognifed in the character of
a celeftial Adam (b) ; and, among the books relating
to thefe dodtrines, which are faid to be loft, mention is
made of Liber Bellorum Domini. The myfteries of the
Pythagorean philofophy, which, according to Philolaus
apud Reuchlinum, fprung from the fame fource, were
alfo ftudied and taught with great fervency during this
period. Mirandola and Paulus Riccius were the firft
who explained the Cabaliftic myfteries in Latin, and the
former, in his Apology* has employed much labour and
learning in defending them, as well as the fcience of na¬
tural magic, from the vulgar idea that necromancy wras
at the bottom of them. His writings, however, upon
that fubjedf were few, and We do not know whether they
ftill exift ; but it may be colledled from the following
propofition in his Conclujiones, and fome others of a fimi-
lar nature, that he, like all the fcholars of his time, had
beftowed much attention upon this ufelefs learning :
“ Qui feierit quid fit denarius in Arithmetica formal!, et
cognoverit natura primi numeri fphserici, feiet fecretum
quinquaginta portarum intelligentiae et magni jobelsei, et
millefimae generationis, et regnum omnium feculorum.”
Thofe who are well acquainted with the tenets of the
modern millenarians will be able to tell whether there
be any connedlion between them and the allufions in
the concluding part of this propofition.
Magic alfo entered deeply into the learning of this
era. This comprifes two diftin£t fciences, that of natu¬
ral magic, and that of daemonology : the firft was con¬
cerned only in the properties of numbers and figures,
and fome of the more hidden properties of nature. This
knowdedge enabled its poffeiTors to produce many effefts
from natural caufes, which, when fcience Was lefs diffu-
fed than at prefent, appeared to be the effedl of fome-
thing fuperior to the common limits of human power.
Albertus, commonly called Magnus, the friend and tu¬
tor of Roger Bacon, was the moft celebrated of thofe
who excelled in this fort of knowledge. This fcience
has been produ&ive of many admirable difeoveries in ma-
P I c
thematics and chemiftry. Magic, in its common figni- Pin.
fication, or necromancy, was alfo eagerly ftudied at this
time, as appears from Cornelius Agrippa’s ftrange work
upon that fubjefl ; and we may judge of the eliimation
in which it was held, by the confelfon that writer
makes in his book De vanitate omnium Scientiarum, that
while he profefled that fcience, he derived more credit
and profit from it, than from any other ufe he ever
could make of his learning. The firft mafter in this
way was faid to be * Solomon, whofe magic ring and * Crini*
glafs are ftill famous in eaftern dsemonology.
But the moft dangerous, the moft popular, and the ix £ dg
moft pernicious delufion which the darknefs of the pre¬
ceding ages had entailed upon mankind, was aftrology,
which will perhaps never be utterly exterminated from
the minds of the vulgar, but which then poffeffed all
ranks. When thefe confiderations are taken into the
account, it mull be looked upon as no defpicable appli¬
cation of learning and talents, to have e.xpofed the fal¬
lacy and abfurdity of this delufion ; and when we recoi¬
led! the great learning and credit of fome of its uphold¬
ers, among whom our countryman Roger Bacon was the
moft efteemed •, the almoft univerfal belief entertained
of it, and the few lights which mankind then poftefied,
as to the real and conftant laws obeyed by the celeftial
bodies 5 it cannot be denied that the twelve books writ¬
ten by Mirandola againft aftrology, the effedt of which,
in opening men’s eyes upon that fubjedi is teftified by a
refpedlable cotemporary author, were the work of a ve¬
ry fuperior and enlightened mind. When we congratu¬
late ourfelves upon our freedom from thefe fuperftitions,
we ought not to forget, that we owe fomething to thofe
who gave the firft blow to them. Proud of the lights
of the age w e live in, when aftrology and fuch like
cheats are no longer in vegue, we are too apt to over¬
look the merit of thofe exertions which firft expofed ansi
refuted them j and to perfuade ourfclves, that in thefe
days of genius and philofophy, fuch exertions would
have been unneceffary •, not recolledling that if we enjoy
many fuperiorities of this kind, we are lefs indebted for
them to our own genius than to the labours of thofe who
firft paved the way for the detedlion of fuperflitious er¬
rors ; our merit is, that we do not (hut our eyes to the
light of fcience; but while wre enjoy its blaze, we
ought to be grateful to thofe who (truck the firft;
fparks.
John Pica of Mirandola has been reprefented by writ¬
ers, whofe ideas are taken from the encomiums of his
cotemporaries, as a mighty prodigy of learning and ge-,
' The diftafte which the prefent times entertain to¬
wards thofe fubjedts upon which he wrote, renders it ve¬
ry difficult, upon a review^ of his works, to think thofe
encomiums juftified. But making allowance for this
change of opinion, and weighing the impartial teftimony
of his equals, and the early age at which he obtained
their admiration, it may be fairly concluded, he was in
reality, a man of very extraordinary powders. Thefe
memoirs are principally colledled from his letters, and
the account given of him by his nephew Francifco, him-
felf
(b) Conjicimus fane, alterum effe Adam cseleftem angelis in coelo demonftratum, unum ex Deo, quem verbo
fecerat, et alterum effe Adam terremim, repulfum a l)cc, quem ex luto manibus fuis finxerat, RtucA/i-
nvs, p. 750.
2
P I c
Plea,
Picard.
[ 535 1
* P. 92.
XPet, Brin
de honrjia
Difcip-
felf an eminent fcholar.' Such a biographer might na
turally be liifpedled of partiality j but the evidence of
other writers fully confirms his account. Paulus Jo-
vius, in his E/ogia DoBorum Virorum, gives the follow¬
ing character of him *. “ John Pica of Mirandola, has
been juftly llyled the phoenix j for in him, the immortal
gods, befides the fplendour of his family, affembled all
the rarelt gifts of body and mind.”
Petrus Kiccius, commonly called Petrus Crinitus, who
was the pupil of Politian and the companion of Miran¬
dola, laments the death of liim and Politian, which hap¬
pened in the fame year, as a public misfortune, more ie-
verely felt at that particular time, when learning, ob-
ftrudted by the incurfion of the French into Italy, want- / and gave
ed the fupport and afliftance pf fuch men To thefe he feized
may be added the teftimony of Hieronymus Savanarola,
who, though afterwards put to death by Pope Alexan¬
der for a heretic, was a man of great confideration on
account of his learning and talents. In a difpute which
took place between him and Mirandola, concerning the
philofophy of the ancients; the former, yielding to the
fuperiority of his opponent, rofe up and embracing him
faid, “ Unus tu es, Pice, setate noftra qui omnium vete-
rum philofophiam ac religionis Chriftianae prtecepta et
II. iihc. 2. leges percalleas ||.” The following epitaph, written by
Hercules Strozza, is preferved by Paulus Jovius r
Joannes facet hie Mirandola ; ccetera norunt
Et Tagus et Ganges, forfan et Antipodes.
Dr Johnfon, in his Effay on Epitaphs, has taken no¬
tice of this pompous diltich, as a warning to epitaph
writers. “ Thus, fays he, have their expedfations been
difappointed, who honoured Picus of Mirandola with
this pompous epitaph. His name, then celebrated in
tire remoteft corners of the earth, is now almoft forgot¬
ten j and his works, then ftudied, admired, and appalud-
ed, are now mouldering in obfeurity.” Monthly Mag.
PICARD, a native of the Netherlands, who found¬
ed a feet the profeflbrs of which were called Picards.-
See Picards.
Picard, John, an able mathematician, and one of
the molt learned aftronomers of the 17th century, was
born at Fleche, and became prieft and prior of Rillie in
Anjou. Going to Paris, he was in 1666 received into
the Academy of Sciences in quality of aftronomer. In
1671, he was fent, by order of the king, to the caftle
of Uraniburg, built by Tycho Brahe in Denmark, to
make aftronomical obfervations there j and from thence
he brought the original manuferipts wrote by Tycho
Brahe, which are the more valuable as they differ in
many places from the printed copies, and contain a
book more than has yet appeared. He made impor¬
tant difeoveries in aflronomy } and was the fir If who
travelled through feveral parts of France, to meafure
a degree of the meridian. His works are, 1. A trea-
tife on levelling. 2. Fragments of dioptrics. 3. Ex¬
periment a circa aquas effluent es. 4. De inenfuris. 5. De
menfura liquidorum & aridorum. 6. A voyage to U-
ramburg, or aftronomical obfervatiens made in Den-
mark. 7. Aftronomical obfervations made in feveral
parts of Irance, &c. Thefe, and fome other of his
works, which are much efteemed, are in the fixth and
leventh volumes of the Memoirs of the Academy of
Sciences. • J
P I G
PICARDS, a religious feci which arofe in Bohemia Picard,
in the 15 th century. —v—-,
Picard, the author of this feft, from wBom it derived
its name, drew after him, as has been ge»erally faid, a
number of men and women, pretending he would reltore
them to the primitive Rate of innocence wherein man
was created : and accordingly he afl'umed the title of
the New Adam. With this pretence he taught his fol¬
lowers to give themfelves up to all impurity j faying
that therein confdled the liberty of the fons of God ;
and that all thofe not of their fedt w^ere in bondage.
He firft publilhed his notions in Germany and the Low-
Countries, and perfuaded many people to go naked,
them the name of Adamites. After this
on an illand in the river Laufnecz, fome
leagues from Thabor, the head quarters of Zrfca,
where he fixed himfelf and his followers. Kis women
were common, but, none rvere allowed to enjoy them
without his permiflion : fo that when any man defired
a particular woman, he carried her to Picard, w ho gave
him leave in thele words, Go, increafe, multiply, andJill
the earth.
At length, however, Zifca, general of the Huflrtes,
(famous for his vi&ories over the emperor Sigifmund),
hurt at their abominations, marched againfl them, made
himfelf mailer of their ifland, and put them all to death
except two4 whom he fpared, that he might learn their
dodlrine.
Such is the account which various writers, relying
on the authorities of Apneas Sylvius and Varillas, have
given of the Picards, w ho appear to have been a party
of the Vaudois, that fled from perfecution in their own
country, and fought refuge in Bohemia. It is indeed
doubtful whether a fc6l of this denomination, charge¬
able with fuch wild principles and fuch licentious con-
duft, ever exifled : and it is certainly aftonifliing that
Mr Bayle, in his art. Picards, fliould adopt the re¬
proachful reprefentations of the writers juft mentioned :
for it appears probable at leaft that the whole is a ca¬
lumny invented and propagated in order to difgrace the
Picards, merely becaufe they deferted the communion
and protefted againll the errors of the church of Rome.
Lafltius informs us, that Picard, together with 40 other
perfons, befides w-omen and children, fettled in Bohemia
in the year 1418. Balbinus the Jefuit, in his Epitome
Rerum Bohemicarum, lib. ii. gives a fimilar account, and
charges on the Picards none of the extravagancies or
crimes aferibed to them by Sylvius. Schle&a, fecretary
of Ladiflaus, king of Bohemia, in his letters to Erafmus
m which he gives a particular account of the Picards,
fays that they confidered the pope, cardinals, and bilhops
of Rome, as the true Antichrifts, and the adorers of the
confecrated elements in the eucharift as downright
idolaters 5 that they denied the corporal prefence of
Chrift in this ordinance ; that they condemned the w-or-
fliip of faints, prayers for the dead, auricular confeflion,
the penance impofed by priefts, the feafts and vigils ob-
ferved in the Romilh church j and that they confined
themfelves to the obfervance of the fabbath, and of the
two great feafts of Chriftmas and Pentecoft. From this
account it would apper.r that they were no other than
the Vaudois; and M. de Beaufobre has fhown that they
were both of the fame feci, though under different de¬
nominations. Befides, it is certain that the Vaudois
were-
PIC [55
Picnrd were fettled in Bohemia in the year 1178, where fome
Piccolom' 0'f t'!lcm adopted the rites of the Grerh, and others thofe
vnj 'of the Latin church. The former were pretty general-
<——v-*-;ly adhered to till the middle of the 14th century, when
the eftablithment of the Latin rites caufed great diftur-
bance. On the commencement of the national troubles
in Bohemia, on account of the oppofition to the papal
power (fee Moravians), the Picards more publicly
avowed and defended their religious opinions ; and they
formed a confiderable body in an ifland by the river
Launitz or Laufnecz, in the diftrifl of Bechin, and re¬
curring to arms, were defeated by Zifca. Enajclop. art.
Picards.
PICARDY, a province in France, is bounded on
the north by Hainault, Artois, and the ftraits of Ca¬
lais j on the eaft by Champagne j on the fouth by the
Lie of France •, and on the weft by Normandy and the
Englifh channel (a). This province is long and nar¬
row, being ufually compared to a bent arm •, and in this
.figure is nearly 156 miles in length, but not above 40
in breadth, and in many places not above 20. It is ge¬
nerally a level country •, and produces wine, fruit of all
kinds, plenty of corn, and great quantities of hay : but
wood being fcarce, moft of the inhabitants burn turf.
They have, however, fome pit-coal, but it is not fo good
as that of England. It was united to the crown of
France in the year 1643 j and is fuppofed to contain
533,000 inhabitants.
Its principal rivers are the Somme, the Oife, the
Canche, the Lanthie, the Lys, the Aa, the Scarpe, and
the Deule.
The fituation of this province on the fea, its many
navigable rivers and canals, with the induftry of the
inhabitants, render it the feat of a flourifhing trade.
In it are made beautiful filk fluffs, woollen fluffs, coarfe
linen, lawn, and foap *, it alfo carries on a large trade
in com and pit-coal. In the diftridls of Calais and
Boulogne are annually bred 5000 or 6000 colts, which
being afterwards turned loofe in the paftures of Nor¬
mandy, are fold for Norman horfes. The fifheries on
this coaft are alfo very advantageous. This province
was formerly divided into Upper, Middle, and Lower
Picardy ; and again fubdivided into four deputy-govern¬
ments. The principal town is Amiens.
PICCOLOMINI, Alexander, archbifhop of Pa¬
tras, and a native of Sienna, where he rvas bom about
the year 1508, was of an illuftrious and ancient family,
which came originally from Rome, but afterwards fet¬
tled at Sienna. He compofed with fuccefs for the
theatre ; but he was not more diftinguilhed by his ge¬
nius, than by the purity of his manners, and his regard
to virtue. His charity was very great •, and was chiefly
exerted in relieving the neceffities of men of letters.
He has left behind him a number of works in Italian.
The moft remarkable of -which are, 1. Various Drama¬
tic Pieces, which laid the firft foundation of his charac¬
ter as a writer. 2. ATreatife on the Sphere. 3. A The¬
ory of the Planets. 4. A Tranflation of Ariftotle’s
G ] PIC
Art of Rhetoric and Poetry, in 410. 5. A Syftem of Piccplorm-
Morality, publifhed at Venice, 1575, in 410; tranflated ni-
into French by Peter de Larivey in 4105 and printed
at Paris, 1581. Thefe, with a variety of other works,
prove his extenfive knowledge in natural philofophv,
mathematics, and theology. He -was the firft who
made ufe of the Italian language in waiting upon pht-
lofophical fubjedls. He died at Sienna the 12th of
March 1578, aged 70. A particular catalogue of his
-works may be feen in the Typographical Didlionary;
There is one performance aferibed to this author, en¬
titled Dialogo della bella Creanta delle Donne, (printed
at Milan, 1558, and at Venice, 1574, in 8vo.) 5 which
but ill fuits the dignity of a prelate. It is filled with
maxims which have an evident tendency to hurt the
morals of young women. Piccolomini’s name, indeed,
is not in the title page j and it has all the appearance
of being a juvenile produdlion. It is very fcarce 5 and
the public would fuftain no lofs by its being entirely
out of print. It was tranflated into French by F.
d’Amboife, and publifhed at Lyons, in i6mo, under the
title of InjlruBion des jeunes dames. It was afterwards
reprinted in 1583, under that of Dialogue is Devis des
Demoifelles.
Piccolomini, Francis, of the fame family with the
foregoing, was born in 1520, and taught philofophy
with fuecefs, for the fpace of 22 years, in the moft ce¬
lebrated univerfities of Italy, and afterwards retired to
Sienna, wdiere he died, in 1604, at the age of 84.
This city went into mourning on his death. His works
are, 1. Some Commentaries upon Ariftotle, printed at
Mayence, 1608, in 4to. 2. Univerfa Phi/ofophia de
Moribus, printed at Venice, 1583, in folio. He la¬
boured to revive the dodlrine of Plato, and endeavoured
alfo to imitate the manners of that philofopher. He had
for his rival the famous James Zabarella, whom he ex¬
celled in facility of expreflion and neatnefs of difeourfe ;
but to whom he was much inferior in point of argu¬
ment, becaufe he did not examine matters to the bottom
as the other did, but preffed too rapidly from one pro-
pofition to another.
Piccolomini of Arragon, O&avius, duke of Amalfi,
prince of the Empire, a general of the emperor’s arm^,
and knight of the order of the Golden Fleece, -was
born in 1599. He firft bore arms among the Spanifh
troops in Italy. He afterwards ferved in the army
of Ferdinand II. who fent him to the relief of Bohe¬
mia, and entrufted him with the command of the im¬
perial troops in 1634. After having fignalized himfelf
at the battle of Nortlingue, he made Marftial de Cha-
tillon raife the fiege of St Omer. He had the good
fortune to gain a vidlory over Marquis de Feuquieres
in 1639: nor did the lofs of the battle of Wolfenbut-
tel, in 1651, impair his glory. He died on the 10th
of Auguft 1656, being five years after, aged 57, with¬
out iffue ; and with the character of an able negotiator
and an adlive general. The celebrated Caprara was his
nephew.
Piccolomini,
(a) The origin of the name of this province does not date earlier than A. D. 1200. It was an academical
ioke *, an epithet firft applied to the quarrelfome humour of thofe ftudents in the umverfity of Paris who came
from the frontier of France and Flanders, and hence to their country Valejii Notitia Galliarum, p. 447. Lorgne-
f-ac, Defcription de la France, p. 5 2.
4
PIC r 557 ] PIC
Piccolo-
mini
Pickering.
Piccolomixi, James, whofe proper name was Anl-
manati, took that of Piccolomini in honour of his patron
Pius II. He was born in a village near Lucca in 1422.
He became bifhop of Mafia, afterwards of Frefcati ; a
cardinal in 1461, under the name of Cardinal de Pavie;
and died in 1479? age °f 57, of an indigeftion of
figs. He left 8000 piftoles in the bankers hands, which
Pope Sixtus IV. claimed ; and of which he gave a part
to the Hofpital of the Holy Ghoft. His works, which
confift of fome Letters, and a hiftory of his own time,
were printed at Milan, in 1521, in folio. His hiftory,
entitled Commentaries, commences the 18 th of June
1464, and ends the 6th of December 1469. They
may very properly be confidered as a Sequel of Pope
Pius II.’s Commentaries, which end with the year
1463. -
Piccolomini, ^Eneas Sylvius. See Pius II.
PICENTTA, (Strabo, Pliny), the capital of the
Picentini, whofe territory, called Ager Picentinus, a
fmall diftricft, lay on the Tufcan fea, from the Promon-
torium Minervce, the fouth boundary of Campania on
the coaft, to the river Silarus, the north boundary of
Lucania, extending within-land as far as the Samnites
and Hirpini, though the exadf termination cannot be
afilgned. The Greeks commonly confound the Picen¬
tini and Picentes, but the Romans carefully diftinguilh
them. The former, with no more than two towns that
can be named, Silernum and Picentia; the fituation of
both doubtful: only Pliny fays the latter flood within-
land, at fome diftance from the fea. Now thought to
be Bicen-za, (Holftenius), in the Principato Citra of
Naples.
PICENUM, (Ccefar, Pliny, Florus) 5 Picenus Acer,
(Cicero, Sallaft, Livy, Tacitus) ; Ager Picentium, (Var-
ro) : a territory of Italy, lying to the eaft of Umbria,
from the Apennine to the Adriatic ; on the coaft ex¬
tending from the river Aefis on the north, as far as the
Prcelutiani to the fouth. In the upper or northern part
of their territory the Umbri excluded them from the
Apennine, as far as Camerinum, (Strabo) ; but in (he
lower or fouthern part they extended from the Adriatic
to the Apennine. A very fruitful territory, and very
populous. Picentes, the people, (Cicero); from the lin¬
gular Picens, (Livy) : different from the Picentini on
the Tufcan fea, though called fo by the Greeks •, but
Ptolemy calls them Piceni, as does alfo Pliny. Their
territory at this day is fuppofed to form the greateft part
of the March of Ancona, (Cluverius).
PICHFORD, in the county of Salop in England 5
on the fouth-eaft fide of Sbrewfhury, near Condover.
It is noted for a fpring of pitchy water (from whence
fome' derive its name), on the top of which there al¬
ways Hows a fort of liquid bitumen. Over moft of the
coal pits in this neighbourhood there lies a ftratum
of blackith rock ; of which, by boiling and grind¬
ing, they make pitch and tar, and alfo diftil an oil
from it.
PICHINCHA, or Pinchinca, a mountain in Peru.
See Peru, N° $6. .
PICKERING, in the north ridmg of Yorkfhire in
England, 13 miles from Scarborough, and 12 ^ from
London, is a pretty large town belonging to the du¬
chy of Lancafter, on a hill among the wild mountains
oi Rlakemore; having the foreft of Pickering on the
north, and Pickering-common on the fouth. It is faid
Vol. XVI. Part II.
to have been built 270 years before Chrift by Perldurus, Pickering
a king of the Britons, who was buried here. It had
once a caftle, the ruins of which are ftill to be feen ; to : ^ ~ j
whofe jurifdidlion many of the neighbouring villages were
fubjeft : and the adjacent territory, commonly called
Pickering- Lath, or the liberty or foreft of Pickering,
•was given by Henry III. to his fon Edmund earl of
Lancafter. A court is kept here for all a&ions under
40s. arifing within the honour of Pickering.
PICKERY, in Scots Law, petty theft, or Healing
things of fmall value.
PICKETS, in fortification, flakes fharp at one end,
and fometimes fhod with iron, ufed in laying out the
ground, of about three feet long ; but, when uled for
pinning the fafcines of a battery, they are from three
to five feet long.
Pickets, in artillery, are about five or fix feet long,
fhod with iron, to pin the park lines, in laying out the
boundaries of the park.
Pickets, in the camp, are alfo flakes of about fix
or eight inches long, to fallen the tent cords, in pitch¬
ing the tents 5 alfo, of about four or five feet long, dri¬
ven into the ground near the tents of the horfemen, to
tie their horfes to.
Picket, an out-guard ported before an army, to give
notice of an enemy approaching.
Picket, a kind of punfihment fo called, where a fol-
dier Hands with one foot upon a fharp pointed flake;
the time of his Handing is limited according to the of¬
fence.
PICKLE, a brine or liquor, commonly compofed of
fait, vinegar, &c. fometimes with the addition of fpices,
wherein meat, fruit, and other things, are preferved and
feafoned.
PICO, one of the Azores iflands, is fo called from
fome lofty mountains on it; or rather from one very
high mountain, terminating like Teneriffe in a peak,
and reputed by fome writers equal to it in height. This '
iftand lies about four leagues fouth-iveft from St George,
twelve from Tercera, and about three leagues fouth-eaft
of Fayal ; in W. Long. 28. '21. and N. Lat. 38. 29.
The mountain Pico, which gives name to- the ifiand, is
filled with difmal dark caverns or volcanoes, which fre¬
quently vomit out flames, fmoke, and allies, to a great
diftance. At the foot of this mountain towards the eaft
is a fpring of frefh water, generally cold, but fometimes
fo heated with the fubterraneous fire, as to rufh forth in
torrents with a kind of ebullition like boiling water ,
equalling that in heat, and fending forth a fleam of ful-
phureous fetid vapours, liquefied ftones, minerals, and
flakes of earth all on fire, in fuch quantities, and with
fuch a violence, as to have formed a kind of promontory
vulgarly called Mysterios, on the declivity of the coaft,
and at the diftance of 1200 paces from* the fountain.
Such at leaft is the account of Ortelius ; though we do
not find this daft circumftance of the promontory con¬
firmed by later obfervations. The circumference of
Pico is computed at about 15 leagues : and its moft; re¬
markable places are Pico, Lagoas, Santa Cruce or Cruz,
San Sebaftian, Pefquin, San Rocko, Playa, and Magda¬
lena; the inhabitants of which live wholly on the pro¬
duce of the ifland, in great plenty and felicity. The
cattle are various, numerous, and excellent in their feve-
ral kinds : it is the lame with the vine j and its juice,
prepared into different wipes, the bell in the. Azores.
3 Y ‘ Befides
Pico
Pidlet.
vol. xiii.
p- 46. See.
Pic [5
Eefides cedar and other timber, they have a kind of
wood which they call teixo, folid and hard as iron ; and
^ veined, when finely polilhed, like a rich fcarlet tabby ;
which colour it has in great perfeftion. The longer it
is kept, the more beautiful it grows: hence it is, that the
teixo tree is felled only for the king’s ufe or by his or¬
der j and is prohibited from being exported as a common
article of trade.
Pico Marina, a fea filh common at Kongo in Africa,
derives its name from the refemblance of its mouth to
Mod. Univ. the beak of a woodpecker. It is of a large fize, and
HjJlory, prodigious flrength, has four fins on its back, three un¬
der its belly, and one on each fide of its head; its tail
is large and forked, by which it cuts the waves with
furprifing force and velocity. It is at war with every
fiih that fwims, and with every thing it meets in its
way, without being intimidated by the largeft veffels j
a furprifing inftance of which intrepidity, we are told by
fume miflionaries, whofe {hip was attacked by one of
them, near thefe coafts, in the dead of night. The vio¬
lence of the fiiock which it gave to the. veffel quickly
awakened the captain and the reft of the people ; who
immediately ran to the {hip’s fide, where they perceived,
by moon light, this huge monitor faftened by its fore¬
head to the veffel, and making the ftrongeft efforts to
difengage itfelf j upon which fome of them tried to pierce
him with their pikes, but he got off before they could
accompliih their aim. On the next morning, upon vi-
fiting that fide of the veffel, they found a piece of the
bony fnout ftuck fait into the wood, and two or three
inches of it projecting outw’ards. In the infide of the
fhip, there was difeovered about five or fix inches more
of the point of the horn, w7hich had penetrated through
the plank. But we mult obferve, that the credulity of
the times probably rendered this animal thus formidable.
PICOUERING, a flying war, or {kirmifli, made by
foldiers detached from two armies for pillage, or before
a main battle begins.
PICOUET, or Picket. See Piquet.
PICRAMNIA, a genus of plants belonging to the
dicecia clafs ; and in the natural method ranking with
thofe that are doubtful. See Botany Index.
PICRANIA AMARA, or Bitter Wood, is a tall and
beautiful timber tree, common in the woods of Jamaica,
belonging to the pentandria clafs of plants. The name
is expreffive of its fenfible qualities.
Every part of this tree is intenfely bitter ; and even
after the tree has been laid for-floors many years, who¬
ever rubs or ferapes the wood, feels a great degree of
bitternefs in their mouth or throat. Cabinet-work
made of this wood is very ufeful, as no infeft wall live
near it.
This tree has a great affinity to the ^uajjia Amara
of Linnaeus} in lieu of which it is ufed as an antifeptic
in putrid fevers. When ufed, lefs of it will do than of
the QuaJJta Amara of Surinam. See Quassia, Bota¬
ny and Materia Medica Index.
PICRIS, Ox-tongue •, a genus of plants, belonging
fo the fyngenefia clafs. See Botany Index.
PICRIUM, a genus of plants, belonging to the te-
trandria clafs; and in the natural method ranking with
thofe that are doubtful. See Botany Index.
PICTET, Benedict, a celebrated divine, was born
at Geneva, in 1655, of a difiinguiflied family, and profe-
cuted his Rudies with great fuccefs. After having travel-
Piets.
38 ] PIC
led into Holland and England, he taught theology in his Piiflet
own country with an extraordinary reputation. The
univerfity of Leyden, after the death of Spantreina, fo-, 
licked him to come and fill his place *, but he thought
that his own country had the belt right to his fervices :
and for that generality he received its thanks by the
mouth of the members of council. A languiffiing dif-
order, occafioned by too much fatigue, haftened his
death : which happened on the 9th of June 17245
the age of 69 years. This miniller had much fweetnefs
and affability in his manner. The poor found in him a
comforter and a father. He publhhed a great number
of works in Latin and French, which are much efteem-
ed in Proteftant countries. The principal of theie are,
I. A Syftem of Chriftian Theology in Latin, 3 vols. in
4to; the beft edition of which is that of 1721. 2. Chrif¬
tian Morality, printed at Geneva, 1710, 8 vols. in
i2mo. 3. The Hiftory of the nth and 12th centu¬
ries ; intended as a fequel to that of Sueur, printed in
1713, 2 vols. in 4to. The Continuator is held in higher
eftimation than the firft author. 4. Several Controver-
fial Treatifes. 5. A great number of trails on morali¬
ty and piety; among which we muff diffinguiih “ the
Art of Living and Dying well 5” publilhed at Geneva,
1705, in i2mo. 6. Some Letters. 7. Some Ser¬
mons, from 1697 to 1721 5 4 vols. in 8vo. With a
vaft number of other books, the names of which it
would be tedious to mention j but which, as Mr Sen-
nebier fays, “ all {how evident marks of piety and good
fenfe.”
Pictet, John-Louis, a counfellor of Geneva, born
in 1739, was of the fame family. He was member of
the Council of Two Hundred ; Counfellor of State and
Syndic ; and died in 1781. He applied himfelf to the
ftudy of aftronomy, and made feveral voyages into France
and England for his improvement. Few men were ever
bleffed with a clearer or more enlightened underftand-
ing. He has left in manufeript the “ Journal of a
Voyage wffiich he made to Ruffia and Siberia in 1768
and 1769, in order to obferve the tranfit of Venus over
the fun’s dilk A wmrk very interefting, from the
lively deferiptions which it gives both of men and of
nature.
PICTLAND. See Pentland. ^
PICTS, the name of one of thofe nations who an-Name,
ciently poffeffed the north of Britain. It is generally
believed that they w'ere fo called from their cuffom of
painting their bodies •, an opinion wThich Camden fup-
ports wflth great erudition. (See Gough’s edition, Vol.
I. p. xci. of the preface). It is certainly liable, howe¬
ver, to confiderable objeftions ; for as this cuftom pre¬
vailed among the other ancient inhabitants of Britain,
wffio ufed the glajlum of Pliny and the vitrum cf Mela
for the like purpofe, it may be alked, Why the name
of Bi&i was "confined by the Romans to only one tribe,
when it was equally applicable to many others ? W hy
fliould they defign them only by an epithet, wnthout ever
annexing their proper name? Or why ffiould they im-
pofe a new name on this people only, when they give
their proper name to every other tribe wffiich they have
occafion to fpeak of ? As thefe queftions cannot be an-
fwered in any fatisfa&ory manner, it is plain we muff
look for fome other derivation of the name.
The Highlanders of Scotland, who fpeak the ancient
language of Caledonia, exprefs the name of this once fa-
mow$
PIC [ S39 ] PIG
| Pi&'. mous nation by the term PiSh'c/i; a name familiar to
v the ears of the moft illiterate, who could never have de¬
rived it from the Roman authors. The word Piclich
means pilferers or plunderers. The appellation wras pro¬
bably impofed upon this people by their neighbours, or
aflumed by themfelves, fomc time after the reign of Ca-
racalla, when the unguarded Rate of the Roman pro¬
vince, on which this people bordered, gave them Se¬
quent opportunities of making incurfions thither, and
committing depredations. Accordingly this name feems
to have been unknown till the end of the 3d century.
Euraenias the panegyrift is the firR Roman author who
mentions this people under their new name of Pidlich,
or, with a Latin termination, Pi£ii. When we fay that
this name may have been probably affumed for the rea-
ron jufi now mentioned, we muR obferve, that, in thofe
of violence, the charafter of a robber was attended
wi: ■ difgrace. If he had the addrefs to form his
fche ■•el!, and to execute them fuccefsfully, he was
rather d than blamed for his conduit; providing
he made no ea: nehments on the property of his own
tribe or any of d allies. We mean this as no peculiar
fligma upon 'he tbits ; for other nations of antiquity, in
the like rude R ite, thought and aited as they did. See
i Thucydides. Jib. iii. p. 3. and Virg. Ain. vii. 745 et 749.
©rigm. Concerning the origin of the Piits, authors are much
divided. Boethius derives them from the Agathyru,
Pomponius Laetus from the Germans, Bede from the
Scythians, Camden (a) and Father Innes from the
ancient Britons, Stillingfleet from a people ^inhabiting
the Cimbrica Cherfonefus, and Keating and O’Flaherty,
on the authority of the Calhel Pfalter, derive them
from the Thracians. But the moR probable opinion
is, that they were the defeendants of the old Caledo¬
nians. Several reafons are urged in fupport of this opi¬
nion by Dr Macpherfon •, and the words of Eumenes,
“ Caledonum, aliorumque Pidlorum, filvas,” &c. plainly
imply that the Pi£ts and Caledonians were one and the
fame people.
As there has been much difpute about the origin of
the PisRs, fo there has been likewife about their language.
There are many reafons which make it plain that their
tongue wras the Gaelic or Celtic ; and thefe reafons are
a further confirmation of their having been of Caledo¬
nian extraft. Through the eafi and north-eafi coafls of
Scotland (which were pofleffed by the Pi els) we meet
3 with an innumerable lifl of names of places, rivers, moun-
Xanguage. tains, &c. which are manifefily Gaelic. From a very
old regifler of the priory of St Andrew’s (Dalrymple’s
Colleftions, p. 122.) it appears, that in the days of
Hungus, the lafi Piflilh king of that name, St An¬
drew’s was called Mukrofs; and that the town now cal¬
led Queen ferry had the name of Ardchinneachan. Both
thefe words are plain Gaelic. The firfl fignifies “ the
heath or promontory of boars }” and the latter, “ the
height or peninfula of Kenneth.” In the HR of Pi£lifir
kings publilhed by Father Innes, moR of the names are
obvioufly Gaelic, and in many inflances the fame with
the names in the HR of Scottifli or Caledonian kings
(a) See Gough's edition of Camden, Vol. I. Preface, p.
39, &c.
publiRied by the fame author. Had Innes underfiood Piets,
any thing of this language, he would not have fuppofed v'~
with Camden that the Picfs fpoke the Britifli tongue.
It was Unlucky that the two wmrds on which they built
their conjedlure (Strath and Aber) are as common in
the Gaelic as they could have been in the Britifh, and
at this day make a part of the names of places in coun¬
tries to which the Pidlilh empire never extended. The
names of Strathfillan and Lochaber may ferve as in¬
flances.
The venerable Bede, as much a Rranger to the Cel¬
tic as either of the antiquaries jufl now mentioned, is
equally unhappy in the fpecimen which he gives of the
Pidtifh language in the word penuahel, “ the head of
the wall.” Allowing the commutation of the initial
p into c, as in fome other cafes, this word has Rill the
fame meaning in Gaelic which Bede gives it in the
Pidlifli. It is true, there might have been then, as well
as now, a confiderable difference between various dia-
lefts of the Celtic 5 and thus, perhaps, that pious author
was led to difeover five languages in Britain agreeably
to the five books of Mofes: A conceit from which the
good man derived a great deal of harmlefs fatisfaftion. ^
The Pidfs of the earlieR ages, as appears from the Termor)',
joint teflimony of all writers who have examined the
fubjeft, poffeffed only the eafl and north-eafl coafl of
Scotland. On one fide, the ancient Drumalbin, or that
ridge of mountains reaching from Lochlomcnd near
Dumbarton to the frith of Tain, which feparates the
county of Sutherland from a part of Rofs, was the
boundary of the Pidlifli dominions. Accordingly we
find in the life of Columba, that, in travelling to the
palace of Brudius, king of the Picls, he travelled over
Drumalbin, the Dorfiutn Eritannue of Adamnan. On
the other fide, the territory of the Picls was bounded
by the Roman province. After Britain was relinquith-
ed by the emperor Honorius, they and the Saxons by
turns wrere maRers of thofe countries which He between
the frith of Edinburgh and the river Tweed. We learn
from Bede, that the Saxons were maRers of Galloway
wdien he finilhed his Ecclefiaflical Hifiory. The Pidls,
however, made a conqueR of that country foon after 5
fo that, before the extinction of their monarchy, all the
territories bounded on the one fide by the Forth and
Clyde, and on the other by the Tweed and Solway, fell
into their hands. -
The hiffory of the PiiRs, as well as of all the other Hiftory.
ancient inhabitants of Britain, is involved in obfeuritv.
The Irifli hiflorians give us a long HR of Pidith kings,
who reigned over Piftavia for the fpace of 11 or 13
centuries before the Chriflian era. After them Innes,
in his Critical Effay, gives us a HR of above fifty, of
whom no lefs than five held the feeptre, each for a whole
century. It is probable that thefe writers had confoun¬
ded the hiffory of the Pi£ls with that of their anceflors
the old Caledonians. In any other view, their accounts
of them are highly fabulous; and have been long ago
confuted by Dr Macpherfon of Slate, an antiquary of
much learning and refearch. The Pifts, as has been
3 Y 2 already .
xc. and the Ancient Univerfal IIft on/, Vol. XVII. p.
PIC [ 540 1 PIC
Pi&s. already obferved, were probably not known by that
name before the 2d or 3d century. Adamnan, abbot
of Iona, is the firft author that exprefsly mentions any
Pidifh king j artd the oldeft after him is Bede. We
are informed by tliefe two writers, that St Columba
converted Brudius king of the Pi£ts to the Chriftian
faith. Columba came into Britain in the year of the
vulgar era 565. Before that period we have no gene¬
ral record to afcertain fo much as the name of any Pic-
tilh king. The hiftory of Drujl or DreJ, who is faid
to have reigned over the Pifts in the beginning of the
fifth century, when St Nmian firft preached the gofpel
to that nation, has all the appearance of fiftion (b).
His having reigned a hundred years, and his putting an
end to a hundred wars, are ftories which exceed all the
bounds of probability.
Brudius, the contemporary of Columba, is the firft
Pidifti king mentioned by any writer of authority.
What figure his anceftors made, or who were his fuc-
ceffors on the throne of Piftavia, cannot be,afcertained.
Bede informs us, that, during the reign of one of them,
the Pi6ts killed Egfred king of Northumberland in bat¬
tle, and deftroyed the greateft part of his army. The
fame author mentions another of their kings called Noi-
tan, for whom he had a particular regard. It was to
this Nait an that Ceolfrid, abbot of Wiremouth, wrote
his famous letter concerning Eafter and the Tonfure
(c) } a letter in which Bede himfelf is fuppofed to have
had a principal hand. Roger Hoveden and Simon of
Durham mention two other Pictifh kings Onnujl and
Kinoth, the firft of whom died 10761, and the latter
flouriftied about the 774, and gave an afylum to Alfred
of Northumberland, who was much about that time ex¬
pelled his kingdom. The accounts given by the Scots
hiftorians of feveral other Piftifh kings cannot be de¬
pended on 5 nor are the ftories told by the Britifh hif¬
torians, Geoffrey of Monmouth and the author of the
Eu/ogium Britannia, worthy of much greater credit.
In the ninth century the Pi ft i fir nation was totally
fubdued by the Scots in the reign of Kenneth Macalpin.
Since that time their name has been loft in that of the
conquerors, with whom they were incorporated after
this conqueft ; however, they feem to have been treated
by the Scottifh kings with great lenity, fo that for feme
ages after they commanded a great deal of refpeft. The
prior of Hogulftead, an old Englifh hiftorian, relates,
that they made a confiderable figure in the army of Da¬
vid the Saint, in his difputes with Stephen king of Eng¬
land, In a battle fought in the year U36,by the Eng¬
lifh on one fide, and the Scots and Pifts on the other,
the latter infilled on their hereditary right of leading the
van of the Scots army, and were indulged in that re-
queft by the king.
The principal feat of the Piftilh kings was at Aber- Fids
nethy. Brudius, however, as appears from the accounts II
given by Adamnan, in his life of Columba, had a■ pa-
lace at Invernefs, which was probably near the extre- > ,
mity of his territory in that quarter j for there is no good
reaibn for believing, with Camden, that this king had
any property in the Weftern Ifles, or that he had made
a gift of Iona to St Columba when he vifited him in that
place. g
With refpeft to the manners and cuftoms of the Manners.
Pifts, there is no reafon to fuppole they were any
other than thofe of the old Caledonians and Scots, of
which many particulars are related in the Greek and
Roman writers who have occafion to fpeak of thole ca¬
tions.
Upon the decline of the Roman empire, cohorts of
barbarians were raifed, and Pifts were invited into the
fervice, by Honorius, when peace was every where re-
ftored, and were named Honoriaci. Thofe under Con-
ftantine opened the paffes of the Pyrenean mountains, and
let the barbarous nations into Spain. From this period
we date the civilization of their manners, which happen¬
ed after they had by themfelves, and then with the Scots,
ravaged this Roman province.
FlCl'S Wall, in antiquity, a wall begun by the em¬
peror Adrian, on the northern bounds of England,- to
prevent the incurfions of the Pifts and Scots. It was
firft made only of turf ftrengthened with palifadoes,
till the emperor Severus, coming into Britain in per-
fon, built it with folid ftone. This wall, part of which
ftill remains, began at the entrance of the Solway frith
in Cumberland, and running north-eaft extended to the
German ocean. See Adrian and Severus.
PICTURE, a piece of painting, or a fubjeft repre-
fented in colours, on wood, canvas, paper, or the like.
See Painting.
PICTURESQUE BEAUTY, fays a late writer on that
fubjeft, refers to “ fuch beautiful objefts as are fuited
to the pencil.” This epithet is chiefly applied to the
works of nature, though it will often apply to works of
art alfo. Thofe objefts are moft properly denominated
pifturefque, which are difpofed by the* hand of, nature
with a mixture of varied mdenefs, Jimplicity, and gran¬
deur. A plain neat garden, with little variation in its
plan, and no ftriking grandeur in its pofition, difplays
too much of art, defign, and uniformity, to be called
pifturefque. “ The ideas' of neat and fmooth (fays
Mr Gilpin), inftead of being pifturefque, in faft dif-
qualify the objeft in which they refide from any preten¬
tions to pifturefque beauty. Nay, farther, we do not
fcruple to affert, that roughnefs forms the moft effential
point of difference between the beautiful and the piftu¬
refque ) as it feems to be that particular quality which ?
makes
(b) According to Camden, this converfion happened about the year 630, in the fouthern Piftilh provinces j
while the northern, which were feparated by fruitful mountains, vrere converted by Columba.
(c) We are told by fome authors that Columba taught the Pifts to celebrate Eafter always on a Sunday between
the 14th and 20th of March, and to obferve a different method of tonfure from the Romans, leaving an imperfeft
appearance of a crown. This occafioned much difpute till Naitan brought his fubjefts at length to the Roman rule.
In that age many of the Pifts went on a pilgrimage to Rome, according to the cuftom of the times •, and amongft
the reft we find two perfons mentioned in the antiquities of St Peter’s church. AJlerius count of the. Pifts, and &jra
wi th his countrymen, performed their Vow.,
PHI [54
Pi&ureique makes objefts chiefly pleafing in painting. I ufe the ge-
Beauty. neral term ronghnefs; but properly fpeaking roughnels
v relates only to the i'urfaces of bodies : when we ipeak of
their delineation, we ufe the word n/ggednefs. Both
ideas, however, equally enter into the pidlurefque, and
both are obfervable in the fmaller as well as in the
larger parts of nature ; in'the outline and bark of a
tree, as in the rude fummit and craggy lides of a moun¬
tain.
Let us then examine our theory by an appeal to
experience, and try how far thefe qualities enter into
the idea of pidlurefque beauty, and how far they mark
that difference among objects which is the ground of our.
inquiry.
“ A piece of Palladian architeflure may be elegant
in*the laft degree-, the proportion of its parts, the pro¬
priety of its ornaments, and the fymmetry of the whole,
may be highly pleafing *, but if we Introduce it in a pic¬
ture, it immediately becomes a formal objedt, and ceafes
to pleafe. Should we wiih to give it picturefque beau¬
ty, we mull ufe the mallet inftead of the chilfel; we mull
beat down one half of it, deface the other, and throw
the mutilated members around in heaps j in fliort, from
a fmooth building we muft turn it into a rough ruin. No
painter who had the choice of the two objects would he-
fltate a moment.
“ Again, why does an elegant piece of garden-
ground make no figure on canvas ? the fliape is plea¬
fing, the combination of the objects harmonious, and
the winding of the W'alk in the very line of beauty. All
this is true ; but the fmoothnefs of the whole, though
right and as it fhould be in nature, offends in picture.
Turn the lawn into a piece of broken ground, plant rug¬
ged oaks in dead of flowering fhrubs, break the edges of
the walk, give it the rudenefs of a road, mark it with
wheel tracks, and fcatter around a few ilones and bruth-
wood ; in a word, inflead of making the whole fmooth,
make it rough, and you make it alfo pifturefque. All
the other in tedients of beauty it already poffeffed.” On
the whole, picturefque compofition confifts in uniting in
one whole, a variety of parts, and thefe parts can only be
obtained from rough ohjeck.
It is poflible, therefore, to find pifturefque ob]e£ls
among works of art, and it is poflible to make objects
fo; but the grand fcene of picturefque beauty is na¬
ture in all its original variety, and In all its irregular
grandeur. “ We feek it (fays our author) among all the
ingredients of landfcape, trees, rocks, broken grounds,
woods, rivers, lakes, plains, valleys, mountains, and di-
ftances. Thefe obiebts in themfelves produce infinite
variety j no tivo rocks or trees are exactly the fame 5
they are varied a feccr.d time by combination ; and al-
moft as much a third time by different lights and {hades
and other aerial effe£ts. Sometimes we find among
them the exhibition of a whole, but oftener we find only
beautiful parts.”
Sublimity or grandeur alone cannot make an objecl
piclurefque: for, as cur author remarks, “ however
grand the mountain or the rocks may be, it has no
claim to this epithet, unlefs its form, its colour, or its
accompaniments, have fome degree of beauty. No¬
thing can be more fublime than the ocean ; but wholly
unaccompanied, it has little of the pifhirefque. When
we talk therefore of a fublime objecl, we always under-
ftand that it is alfo beautiful ? and we call it fublime or
i ? P H’ I
. { .
beautiful only as the ideas of Sublimity or Ample beauty Pidlurefque
prevail. But it is not only the form and the compofi- ^tauty- 1
tion of the objects of landfcape which the picturefque r
eye examines ; it connects them with the atmofphere,
and feeks for all thofe various effects which are produ¬
ced from that vail and wonderful ftorehoufe of nature.
Nor is there in travelling a greater pleafure than when
a fcene of grandeur burits unexpectedly upon the eye,
accompanied with fome accidental circumitance of the
atmofphere which harmonizes with it, and gives it
double value.”
There are few places io barren as to afford no pic¬
turefque fcene.
    —Believe the mufe,
She does not know that inaufpicious fpot
Where beauty is thus niggard of her Itore.
Believe the mufe, through this terfeftrial wafte
The feeds of grace are fown, profufely town,
Even where we lealt may hope 
Mr Gilpin mentions the great military road between
Newcattle and Carlifle as the mod barren tradl of
country in England j and yet there, he fays, there is
“ always fomething to amufe the eye. The inter¬
changeable patches of heath and green-fveard make an
agreeable variety. Often too on thefe vaft tradls of
interfering grounds we fee beautiful lights, foftening
off along the fides of hills j and often we fee them
adorned with cattle, flocks of ffieep, heath-cocks, greus,
plover, and flights of other wild fowl. A group of cat¬
tle Handing in the thade on the edge of a dark hill, and
relieved by a lighter diffance beyond them, will often
make a complete picture without any other accompani¬
ment. In many other fituations alfo we find them won¬
derfully pleafing, and capable of making pictures amidff
all the deficiencies of landfcape. Even a winding road
itfelf is an objedl of beauty j while the richnefs of the
heath on each fide, with the little hillocks and crum¬
bling earth, give many an excellent leffon for a fore¬
ground. When we have no opportunity of examining
the grand feenery of nature, we have everywhere at leaff
the means of obferving with what a multiplicity of parts,
and yet with what general fimplicity, ihe covers every
fuface.
“ But if we let the imagination loofe, even feenes
like thefe adminilter great amufement. The imagi¬
nation can plant hills ; can form rivers and lakes in
valleys ; can build caflles and abbeys and, if it find
no other amufement, can dilate iiielf in vaft ideas of
fpace.”-
Mr Gilpin, after deferibing fuch objedls as may be
called pidlurelque, proceeds to confider their fources of-
amufement. We cannot follow our ingenious author
through the whole of this confideration, and fliall there¬
fore finifh our article with a lliort quotation from the be¬
ginning of it. “ We might begin (fays he) in moral
ftyle, and cpnfider the obje&s of nature in a higher light
than merely as amufement. We might obferve, that a
fcarcli after beauty fhould naturally lead the mind to
the great origin of all beauty ; to the
   firft good, firft perfect, and firft fair.
But though in theory this feems a natural climax, we
infill the lefs upon it, as in faft we have fcarce ground
to hope that every admirer of pidurefque beauty is an
admirer
P I E
Picturefque
Beauty
II
Piece.
admirer alfo of the beauty of virtue ; and that every
lover of nature relle&s, that
t 542 ]
P I E
Nature is but a name for an effeH,
Whofe caufe is God.. —
If, however, the admirer of nature can turn Ids amufe-
ments to a higher purpofe j if its great fcenes can in-
fpire him with religious awe, or its tranquil fcenes
with that complacency of mind which is fo nearly al¬
lied that benevolence, it is certainly the better. Apponat
lucro. It is fo much into the bargain ; for we dare not
promife him more from pidturefque travel than a ra¬
tional and agreeable amufement. Yet even this may
be of fome ufe in an age teeming with licentious plea-
fure ; and may in this light at leaft be conhdered as ha¬
ving a moral tendency.”
PICUIPINIMA, is the Brafilian name of a fpecies
of pigeon, which is fo very fmall as fcarcely to exceed
the lark in fize.
PICUMNUS and Pilumnus, were trvo Roman
deities, who prefided over the aufpices required before
the celebration of nuptials. Pilumnus was fuppofed to
patronize children, as his name feems in fome manner to
indicate quodpellat mala infantice. I he manuring of
land was firft invented by Picumnus, from which reafon
he is called Sterquilinius. Pilumnus is alfo invoked as
the god of bakers and millers, as he is faid to have firft
invented the art of grinding corn.
PICUS, the Woodpecker, a genus of birds be¬
longing to the order of pica:. See Ornithology
Index.
Picus (fab. hift.), a king of Latium, fon of Sa¬
turn. He married Venilia, alfo called Canens, by
whom he had Faunus. He was tenderly loved by the
goddefs Pomona, and he returned her affe&ion. As he
was one day hunting in the woods, he was met by Circe,
who became deeply enamoured of him, and who changed
him into a woodpecker, called by the name of picus
among the Latins. His wife Venilia was fo difconfo-
late when Are was informed of his death, that ihe pined
away. Some fuppofe that Picus was the fon of Pilum¬
nus, and that he gave out prophecies to his fubjedts by
means of a favourite woodpecker •, from which circum-
flance originated the fable of his being metamorphofed
into a bird.
Picus, John Francis, prince of Mirandola, nephew of
John Pica or Picus, mentioned above, was born about the
year 1469. He cultivated learning and the fciences af¬
ter the example of his uncle ; but he had a principality
and dominions to fuperintend, which involved him in
great troubles, and at laft coft him his life. He was
twice driven from his principality, and twice reftored ;
and at laft, in 1533, was, together with his eldeft fon
Albert, aflaftinated in his own caftle by his nephew Ga-
leoti. He was a great lover of letters •, and fuch of his
works as were then compofed were inferted in the Straf-
burgh edition of his uncle’s in 1504, and continued in
future impreffions, befides fome others which were never
collected.
PIECE, in matters of money, fignifies fometimes
the fame thing with fpecies; and fometimes, by adding
the value of the pieces, it is ufed to exprefs fuch as have
no other particular name. lor the piece of eight, or pi-
aftre, fee MONEY Table.
Piece, is alfo a kind of money of account, or rather
manner of accounting, ufed among the negroes on the Piece,
coaft of Angola in Africa. See MONE T Table. ' Piedmont.
Piece, in Heraldry, denotes an ordinary or charge. v
The honourable pieces of the ftiieid are the chief, fefs,
bend, pale, bar, crofs, faltier, chevron, and in gene¬
ral all thofe which may take up one-third of the field,
when alone, and in what manner foever it be. See
Heraldry.
Pieces, in the military art, include all forts of great
guns and mortars. Battering pieces are the larger
lort of guns ufed at fieges for making the breaches j
fuch are the 24-pounder and culverine, the one carry¬
ing a 24 and the other an 18 pound ball. Field-pieces
are 1 2-pounds, demiculverines, 6-pounders, fackers, mi¬
nions, and 3-pounders, which march with the army, and
encamp always behind the fecond line, but in day of
battle are in the front. A foldier’s firelock is likewife
called his piece.
PIEDMONT, a country of Italy, having formerly
the title of a principality, is bounded on the north by
Savoy and Italy 5 on the weft by France $ on the fouth
by the Mediterranean and the republic of Genoa ; and
on the eaft by the duchies of Montferrat and Milan}
extending about 150 miles from north to fouth, but
much lefs from eaft: t® weft. It is called Piedmont, and
in Latin Piedrnontium, from its fituation at the foot of
the mountains, or Alps, which feparate France from
Italy. This country is in fome parts mountainous, but
is everywhere very fruitful. The plains produce fine
corn, and Montferrat and the Milanefe yield great quan¬
tities of Turkey wheat, which commonly ferves for
bread, and with which the people of the middle rank
mix rye ; the pods are ufed for fuel, and the ftalks be¬
ing thick ferve to mend the roads. The hills produce
plenty of wine, which, like the Italian wanes, is very
lufeious wdien new, efpecially the white. There is
alfo a tarthh red wine called vino brufeo, faid to be very
wdiolefome for fat people, and, on the other hand, the
fweet wine is recommended as a ftomachic. The
neighbourhood of Turin is famous for its fine fruits,
and many long walks of chefnut and mulberry trees,
which produce both pleafure and profit. Marons, or
large chefnuts, are a favourite dainty among the com¬
mon people. Thefe are put into an oven, and, when
thoroughly hot, and cooled in red wane, are dryed a
fecond time in the oven, and afterwards eaten cold.
Truffles grow here in fuch abundance, that Piedmont
has obtained the name of the truffle country. Some are
black, others white marbled with red. Their price is
rated according to their fize. Sometimes they are
found of 12 or 14 pounds weight j and many country
people earn from 60 to 70 dollars a-year merely by dig¬
ging for them. The trade in cattle is faid to bring
into Piedmont no lefs than three millions of livres per
annum. The cultivation of filk is alfo a profitable arti¬
cle, the Piedmontefe filk being, on account of its fine-
nefs and ftrength, efteemed the beft in Italy, ihe Pied¬
montefe gentry breed vaft numbers of filk-worms un¬
der the care of their tenants, who have the eggs and
mulberry leaves delivered to them, and in return they
give half the filk to their mafters. This principality
comprehends eleven fmall provinces : Piedmont proper,
the valleys between France and Italy, the valley of
Saluza, the county of Nice, the marquifate of Sufa,
the duchy of Aoft, the Canavefe, the lordfhip of Vet-
fail.
PIE [ 543 ] PIE
Piedmont, fail, the county of Aft, and the Langes. It was for-
merly a part of •Lombardy, but now belongs to the
king of Sardinia, and lies at the foot of the Alps,
which feparate France from Italy. It contains many
high mountains, among which there are rich and fruit¬
ful valleys, as pleafant and populous as any part of Italy.
In the mountains are mines of feveral kinds, and the
forefts afford a great deal of curious game, among which
the tumor is an ufeful animal. “ The mules (fays Mr
Watkins) are very fine in this country ; but the inhabi¬
tants have other beafts, or rather monfters which they
find very ferviceable, though vicious and obftinate.
Thefe are produced by a cow and an afs, or mare and
bull, and called jumarres or gimerri (a). I cannot fay
that I have ever feen any of them, but I am told they
are very common.”
The Piedmontefe are faid to be more intelligent
than the Savoyards, but lefs fincere. Some authors
reprefent them as lively, artful, and witty, the inhabi¬
tants of the mountain of Aofta excepted, who are far¬
ther diftinguiihed by large wens, as even their horfes,
dogs, and other animals. Mr Baretti, however, in his
Account of Italy, vol. ii. p. 116. gives the following ac¬
count of them. “ One of the chief qualities (fays he),
which diftinguifh the Piedmontefe from all other Ita¬
lians, is their want of cheerfulnefs. Piedmont never
produced a fingle good poet, as far as the records of
the country can go, whereas there is no other province
of Italy but what can boaft of fome poet ancient or
modern ; and yet the Piedmontefe are not deficient in
feveral branches of learning, and fome of them have
fucceeded tolerably well in civil law, phyfic, and the
mathematics. It is likewife obferved of this people,
that none of them ever attained to any degree of ex¬
cellence in the polite arts, and it is but lately that they
can boaft of a painter, Cavaliero Bomente $ a ftatuary,
Signor Lodetto j and fome architects, Conte Alfieri,
Signor Borra, and others, who yet, to fay the truth,
are far inferior to numberlefs artifts produced by the
other provinces of Italy. They have, on the other
hand, greatly advanced when confidered as foldiers j
though their troops have never been very numerous,
every body converfant in hiftory knows the brave ftand
they made for fome centuries paft againft the French,
Spaniards, and Germans, whenever they have been in¬
vaded by thefe nations. The Ikill of the Piedmontefe
in fortification is likewife very great, and their Berto-
las and Pintos have ftiown as much genius as the Vau-
bans and Cohorns, in rendering impregnable feveral
places which inferior engineers would only have made
fecure.”
Payne's "The chief trade of this principality confifts in hemp
Geog- and filk. Indeed, fo great is their trade in raw filk,
vo. ii. that the Englifh alone have purchafed to the value of
200,000 lib. in a year. The filk worm thrives fo well,
that many peafants make above (b) ioo lib. of filk an¬
nually; and it is not only abundant, but univerfally Piedmont, •
known to be ftronger and finer than any in Italy. The , ptenes- ,
land owners divide the profit with their tenants. The v "
Piedmontefe workmen, however, are faid to want ex-
pertnefs, though they finith their work equally well
with thofe of other nations. The high duty and land-
carriage on mules likewife tend to leffen the value of
this trade. They have befides corn, rice, wine, fruits,
flax, and cattle.
In the valleys of Lucerne, Peyroufe, and St Martin,
which have always belonged to Piedmont, live the cele¬
brated Waldenfes or Vaudois, a name which fignifies
people of the valleys. Thefe have rendered themfelves
famous in hiftory for their diffent from the Romifti
church long before the time of Luther and Calvin, and
for the pertecutions they have fuffered on that account $
but fince the year 1730 they have not been openly mo-
lefted for their religion, but, in order to fupprefs jhem
by degrees, a popiih church has been built in every pa-
rifti. They are heavily taxed, and labour under great
oppreffions. The number of people in thefe valleys
fcarce at prefent exceeds 10,coo, of which 1000 are
Catholics. The chief river of Piedmont is the Po, which
flows out of Mount Vifo. The river Sella, the Doria,
Baltea, the ancient Druria, the Tenaro, and feveral
others, run into it. The Var, anciently called the Va¬
rus, rifes in the county of Nice, and after watering it
empties itfelf into the Mediterranean. The language of
the Piedmontefe is a mixture of French and Italian. In
this country are about 50 earldoms, 15 marquifates, a
multitude of lordlhips, and 20 abbeys. Though the
country be entirely popilh, except fome valleys inhabit¬
ed by the Waldenfes, the king referves to himfelf the
greateft part of the power in church affairs, which in
many other places is given up to the pope, and the con-
ftitution unigenitus is here univerfally oppofed. Towards
the end of the 17th century, the French king perfuaded
the duke of Savoy to drive them out of the country ; in
confequence of which 200,000 of them retired to Ger¬
many, England, and Holland, and yet they are not all
extirpated, though, as we have obferved, they are obliged
to have a Roman Catholic church in every parilh.
Turin, formerly the refidence of the king of Sardinia,
to whom this principality belonged, is the chief city.
See Turin. The number of inhabitants, Mr Watkins
fays, in Piedmont and Savoy, amount to 2,695,727
fouls, of which Turin contains about 77,000. Pied¬
mont, as well as the reft of Italy, few of our readers
need be informed, is now fubjedl to the overgrown power
of France.
PIENES, a fmall ifland of Japan, oppofite to the
harbour of Saccai, is famed not only for the beauty of
its walks, to which crowds of people refort from the
city, but for a deity worftiipped there, to which vafl,
numbers of perfons devote themfelves. They go from,
his temple to the fea fide, where they enter into a boat
provided
(A) Thefe equivocal animals, however, if we may fo term them, are fo generally mentioned by travellers in
this part of Europe, that we have no doubt of their exiftence, or of their being found hardy and ferviceable as
labourers.
(b) Each pound is valued in Piedmont at 18s. The little village of La Tour, in the valley of Lucerne, makes
above 50,000 lb. annually, and the exports every year to the fingle city of Lyons amount to more than 16o,oool>
PIE [ 544 ] PIE
Pienes provided for the purpofe } tlien, launching into the deep,
p cJ'r| ,s they throw theinfelves overboard, loaded with it ones, and
''' ' fink to tlie bottom. The temple of that deity, which is
called Canon, is very large and lofty, and fo are many
others in the city itfelf j one in particular, dedicated to
the gods of other countries, is thought the finell in the
whole empire.
PIEPOUDRE, Court of, the ioweft, and at the
fame time the moil expeditious, court of juftice known
to the lawr of England. It is called piepoudre, (curia
pedis pulverizati), from the dully feet of the fuitors j or,
according to Sir1 Edward Coke, becaufe jufhee is there
done as fpeedily as duft can fall from the foot: CTpon
the fame principle that juftice among the Jews wras ad-
miniftered in the gate of the city, that the proceedings
might be the more fpeedy, as w7ell as public. But the
etymology given us by a learned modem w-riter is
much more ingenious and fatisfadlory •, it being de¬
rived, according to him, from pitdpuldrecux, “ a ped¬
lar,” in old French, and therefore fignifying the court
of fuch petty chapmen as refort to fairs or markets. It
is a court of record incident to every fair and market;
of which the ftewTard of him who owns or has the toll of
the market is the judge. It w as inftituted to adminifter
juftice for all commercial injuries done in that very fair
or market, and not in any preceding one. So that the
injury mnft be done, complained of, heard, and deter¬
mined, within the compafs of one and the fame day, un-
lefs the fair continues longer. The court hath cogniz¬
ance of all matters of contradl that can poffibly arife
within the precinct of that fair or market j and the plain¬
tiff muff make oath that the caufe of an action arofe
there. From this court a writ of error lies, in the na¬
ture of an appeal, to the courts at Weftminfter. The
reafon of its inftitution feems to have been, to do juftice
expeditioufiy among the variety of perfons that refort
from diftant places to a fair or market ; lince it is pro¬
bable, that no other inferior court might be able to
ferve its procefs, or execute its judgements, on both or
perhaps either of the parties ; and therefore, unlefs this
court had been erefled, the complain^ muft neccffarily
have reforted even in the firft inftance to fome fuperior
judicature.
PIER, in building, denotes a mafs of Hone, &c.
oppofed by way of fortrefs to the force of the fea, or
a great river, for the fecurity of mips that lie at harbour
in any haven.
Piers of a Bridge. See Bridge.
PIERCEA. See Rivinia.
PIERIA, in Ancient Geography, a di ft riel of Mace¬
donia, contained between the mouths of the rivers Lu-
dias and Peneus; extended by Strabo beyond the Lu-
dias, to the river Axios on the north, and on the fouth
no farther than the Aliacmon, along the weft fide of
the Sinus Thermaicus.—Another Plena of Syria, the
north part of Seleucia, or the Antiochena, fituated on
the Sinus Iflicus, and lying next Cilicia to the north-
•weft.
PIERIDES, in fabulous hiftory, the daughters of
* Pierus a Macedonian prince, prefaming to difpute with
the mufes for the prize of poetry, w7ere turned into mag¬
pies. The name of Piendes was alfo given to the mufes,
from Mount Pieris in ThelLly, which was ccnfecrated
to them ; or, according to others, from Fieris, a Thtf-
falian poet, who wras the firft who facrificed to them. Piemio
See Pieris. . (1
PIERINO DEL Vaga, an eminent Italian painter. t *!e^ie'
born of poor parents in Tufcany, about, the year 1500.
He was placed apprentice with a giocer in Florence,
and got fome inltrudtions from the painters to whom
he was fent with colours and pencils j but a painter
named Vaga taking him to Rome, he was called Del
Vaga, from living with him, his real name bei»g Bua-
nacorfi. He ftudied anatomy with the fciences necef-
fary for his profeflion ; and had fomewhat of every
thing that was good in his compofilions. After Ra¬
phael’s death, he joined with Julio Romano and Fran-
eifeo Penni to finilh the wrorks in the Vatican which
were left imperfedl by their common mailer ; and to
confirm their friendfhip married Penni’s lifter. He gain¬
ed the higheft reputation by his performances in the pa¬
lace of Prince Doria at Genoa : but the multiplicity- of
his bufinefs, and the vivacity of his imagination, drained
his fpirits in the flower of his age ; for he died in the
year 1547. Of all Raphael’s, difciples, Pierino kept
the charaifler of his mailer longeft, i. e. his exterior
charadler and manner of defigning j for he fell very fliort
of the finenefs of Raphael’s thinking. Pie had a parti¬
cular .genius for the decoration of places according to
their cuftcms. His invention in that kind of painting
was full of ingenuity j grace and order are everywhere
to be met with, and his difpofilions, wdrich are ordinary
in his pictures, are wonderful in his ornaments: fome of
thefe he has made little, and fome great, and placed them
both with fo much art, that they let off one another by
comparifon and contrail. His figures are difpofed and
defigned according to Raphael’s guflo ; and if Raphael
gave him at fhft fome flight fkelches of ornaments, as
he did to Giovanni d’Udine, he executed them to admi¬
ration. The tapeftries of the leyen planets, in feven
pieces, which Pierino defigned for Diana de Poitiers,
and which were, when De Piles wrote, with Monfieur
the firft prefident at Paris, {hows fufficiently what he
wras, and that the above character does not exceed the
truth.
PIERIS, in Ancient Geography, a mountain which
is thought to have given name to Fieri a of Macedonia •,
taking its name from Pierus a poet, who was the firil
that facrificed to the Mufes, thence called Pierides,
if credit may be given to an ancient fcholiaft on Juve¬
nal.
PIERRE d’automne is a French name, tranfiated
from the Chinefe, of a medicinal Hone, celebrated in
the call for curing all diforders of the lungs. Many
imagine it had its name of the autumn-ftone from its
being only to be made at that feafon of the year ; but
it may certainly be made equally at all times, j he
Chinefe ehemifts refer the various parts of the body to
the feveral feafons of the year, and thus they refer the
lungs to autumn. This is evident in their writings, arid
thus the Hone for difeafes of the lungs came to be called
autumn-jlone. Is is prepared as follows : They put 30
pints of the urine of a ftrong and healthy young man
into a large iron pot, and fet it over a gentle fire.
When it begins to boil, they add to it, drop by drop,
about a large tea-cup-full of rape oil. They then leave
it on the lire till the whole is evaporated to a thick fub-
ftance like black mud. It is then taken out of the pot,
and
2
P I E
[ 545 ]
P I E
Kerxc, and laid on a flat iron to dry, fo that it may be powder-
Pietllts‘ , ed very fine. This powder is moiftened with frelh oil,
> and the mafs is put into a double crucible, furrounded
with coals, where it Hands till it be thoroughly dried
again. This is again powdered, and put into a china
veflel, which being covered with filk cloth and a double
paper, they pour on it boiling water, which makes its
way, drop by drop, through thefe coverings, till fo much
is got in as is fufficient to reduce it to a pafte. This
palte is well mixed together in the veffel it is kept in,
and this is put into a veffel of water, and the whole fet
over the fire. The matter thus becomes again dried in
balneo marine, and is then finithed. Obferv. fur les
Cout. de l'Afie, p. 258.
Pierre, <SV, is a large river in North America,
fcarcely inferior to the Rhine or the Danube, and navi¬
gable almoft to its fource. Together with many other
large ftreams, it falls into the great river Mifliflippi.
Pierre, -S'/, or St Peter's, the capital of Martinico,
was built in 1665, in order to overawe the mutineers of
the ifland who rebelled againlt its proprietors, the fecond
Weft India company, who were at the fame time the
proprietors of all the French Antilles. It is fituated on
the weftern fide of the ifland. The town extends along
the fhore, and a battery that commands the road is erect¬
ed on#the weft fide, which is waftied by the river Royo-
lan, or St Peter. The town is divided into three wards j
the middle, which is properly St Peter’s, begins at the
fort, and runs weftward to the battery of St Nicholas.
Under the walls of the fecond ward (hips at anchor ride
more fecurely than under the fort, on which account
this ward is called the Anchorage. The third ward, cal¬
led the Gallery, extends along the fea fide from Fort St
Peter to the Jefuits River, and is the moft populous part
of the city. The houfes of St Peter’s ward are neat,
Commodious, and elegant, particularly thofe of the go¬
vernor of the ifland, the intendant, and the other offi¬
cers. The pariffi church of St Peter is a magnificent
ftone building which belonged to the Jefuits, with a
noble front of the Doric order. The church of the An¬
chorage, which belongs to the Jacobine friars, is like-
wife of ftone. It is a place of confiderable trade, and
is built with tolerable regularity. The houfes are moftly
conftrufted of a gray pumice-ftone or lava, which is
found on the ftrand } and the high-ftreet is, according
to Dr Ifert, above an Englifli mile in length. It is
fuppofed to contain about 2000 houfes, and 30,000 in¬
habitants, including negroes. St Pierre, with the whole
of the flourilhing ifland of Martinico, was taken from
the French in the month of March 1794, by the Britiffi
troops : 125 veffels loaded with the produce of the ifland,
and of great value, were captured, 71 of which were in
the harbour of St Pierre.
PIETISTS, a religious feft, fprung up among the
Proteftants of Germany, feeming to be a kind of mean
between the Quakers of England and the Quietifts of
the Romiffi church. They defpife all forts of ecclefi-
aftical polity, all fchool theology, and all forms and
ceremonies, and give themfelves up to contemplation
and the myftic theology. Many grofs errors are charged
on the Pietifts, in a book entitled Manipulus Obferva-
tionum Antipietijiicarum ; but they have much of the air
of polemical exaggeration, and are certainly not at all
juft. Indeed there are Pietifts of various kinds : Some
running into grofs illufions, and carrying their errors to
VOL. XVI. Part II.
the overturning of a great part of the Chriflian do&rine,
while others are only vifionaries j and others are very
honeft and good, though perhaps mifguided, people. _
They have been difgufted with the coldnefs and forma¬
lity of other churches, and have thence become charm¬
ed with the fervent piety of the Pietifts, and attached to
their party, without giving into the groffeft of their er¬
rors. See Mojheim's Eccl. Hi/lory, vol. iv. p. 454.
Pietists, otherwife called the Brethren and Sifters
of the Pious and Chriftian Schools, a fociety formed in
the year 1678 by Nicholas Barre, and obliged by their
engagements to devote themfelves to the education of
poor children of both fexes.
PIETOLA, anciently called Andes, is a place with¬
in two Italian miles of Mantua, famous for being the
birthplace of Virgil.
PIETY, is a virtue winch denotes veneration for the
Deity, and love and tendemefs to our friends. This di-
ftinguiffied virtue, like many others, received among the
Romans divine honours, and wras made one of their gods.
Acilius Glabrio firft erefted a temple to this divinity,
which he did upon the fpot on wfliich a vToman had fed
with her own milk her aged father, who had been irn-
prifoned by order of the fenate, and deprived of all ali¬
ments. The ftory is well known, and is given at length
in authors which are in the hands of every fchoolboy.
See Cicero de div. 1. and Valerius Maximus, v. c. 4. and
our article FILIAL Piety.
If piety was thus praftifed and thus honoured in
Heathen antiquity, it furely ought not to be lefs fo,
among Chriftians, to whom its nature is better defined,
and to the practice of winch they have motives of great¬
er cogency. A learned and elegant writer has faid that
the want of piety arifes from the want of fenfibility *, and
his obfervations and arguments are fo juft and fo well ex-
preffed, that we cannot do better than tranfcribe them.
“ It appears to me (fays Dr Knox), that the mind
of man, wiien it is free from natural defeats and acquir¬
ed corraption, feels no lefs a tendency to the indulgence
of devotion than to virtuous love, or to any other of the
more refined and elevated affections. But debauchery
and excefs contribute greatly to deftroy all the fufcep-
tible delicacy with which nature ufually furniffies the
heart; and, in the general extinction of our better qua¬
lities, it is no wonder that fo pure a fentiment as that of
piety ffiould be one of the firft to expire.
“ It is certain that the underftanding may be improv¬
ed in a knowledge of the wrorld, and in the arts of fuc-
ceeding in it, while the heart, or wffiatever conftitutes
the feat of the moral and fentimental feelings, is gra¬
dually receding from its proper and original perfection.
Indeed experience feems to evince, that it is hardly pof-
fible to arrive at the character of a complete man of the
world, without lofing many of the moft valuable fenti-
ments of uncorrupted nature. A complete man of the
world is an artificial being j he has difcarded many of
the native and laudable tendencies of his mind, and
adopted a new fyftem of objeCts and propenfities of his
owm creation. Thefe are commonly grofs, coarfe, fordid,
felfiffi, and fenfual. All, or either of thefe attributes,
tend direCtly to blunt the fenfe of every thing liberal,
enlarged, difinterefted ; of every thing which partici¬
pates more of an intellectual than of a fenfual nature.
When t^ie heart is tied do»vn to the earth by luft and
avarice, it is not extraordinary that the eye fliould be
3 Z feldom
p I
Piety, feldom lifted up to heaven. _
Sunday (becaufe he thinks tne day fit for little elfe) in
the counting-houfe, in travelling, in the tavern, or in the
brothel, thofe who go to church appear as fools, and the
bufinefs they go upon as nonfenle. He is callous to the
feelings of devotion j but he is tremblingly alive to all that
.gratifies his fenfes or promotes his intereft.
“ It has been remarked of thofe writers who have at¬
tacked Chriftianity, and reprefented all religions merely
as diverfified modes of fuperftition, that they were in¬
deed, for the moft part, men of a metaphyiical and a
difputatious turn of mind, but ufually little diftinguithed
for benignity and generofity. There was, amidft all
their preteniions to logical fagacity, a cloudineis of
ideas, and a coldnefs of heart, w'hich rendered them
verv unfit judges on a queftion in which the heart is
chiefly interefted 5 in which the language of nature is
more expreflive and convincing, than all the dreary fub-
tleties of the difmal metaphyficians. Even the reafon-
ing faculty, on which we fo greatly value ourfelves, may
he perverted by exceflive refinement; and there is an ab-
ilrufe, but vain and foolilh philofophy, which philofo-
phizes us out of the nobleft parts of our noble nature.
One of thofe parts of us is our inftinftive fenfe of reli¬
gion, of which not one of thofe brutes which the philo-
fophers moil admire, and to whofe rank they wiih to re¬
duce us, is found in the flighteil degree to participate.
“ Such philofophers may be called, in a double fenie,
the enemies of mankind. They not only endeavour to
entice man from his duty, but to rob him ot a moft ex¬
alted and natural pleamre. Such, furely, is the _plea-
iure of devotion. For when the loul rifes above this lit¬
tle orb, and pours its adoration at the throne of celeftial
majefty, the holy fervour which it feels is itfelf a rapturous
delight. Neither is this a declamatory reprefentation, but
a truth felt and acknowledged by all the fons of men j
except thofe wdio have been defeftive in fenfibility, or
who hoped to gratify the pride or the malignity of their
hearts by fingular and pernicious fpeculation.
“ Indeed all difputatious, controverfial, and metaphy-
fical writings on the fubjeft of religion, are unfavourable
1.0 genuine piety. We do not find that the moft renorvn-
cd polemics in the church militant were at all more at¬
tentive than others to the common offices of religion, or
that they were a&uated by any peculiar degree of devo¬
tion. The truth is, their religion centered in their heads,
whereas its natural region is the heart. The heart ! con¬
fined, alas ! in colleges or libraries, unacquainted with all
the tender charities of hufband, father, brother, friend }
fome of them have almoft forgotten that they poffefs a
heart. It has long ceafed to beat with the pulfations of
love and fympathy, and has been engrofled by pride on
conquering an adverfary in the fyllogiftic combat, or by
impotent anger on a defeat. With fuch habits, and fo
defective a fyftem of feelings, can we expeft that. a. doc¬
tor of the Sorbonne, or the disputing profefibr of divinity,
Ihould ever feel the pure flame of piety that glowed in the
hofcms of Mrs Rowe, Mrs Talbot, or Mr Nelfon ?
“ It is however certain, that a devotional tafte and
habit are very defirable in themfelves, exclufive of their
eifects in meliorating the morals and difpofition, and
promoting prefent and future felicity. I hey add dig¬
nity, pleafure, and fecurity to any age : but to old age
they are the moft: becoming grace, the moft fubftan-
tial fupport, and the fweeteft comfort. In order to pre-
E [ 546 ] PIG
To the man who fpends his ferve them, it will be neceffary to preferve our fenfibihty } Piety
and nothing will contribute fo much to this purpofe as a p.
life of temperance, innocence, and fimplicity.” c—  ’
Of piety, as it denotes love and tendernefs to our
friends, there have been many diftinguilhed inftances
both in ancient and modern times. See FILIAL Piety,
Fraternal and Parental Affection, &c.
The following example of filial piety in China, ta¬
ken from P. Du Halde’s defeription of that country,
will not ive truft be difagreeable to our readers. “ In
the commencement of the dynafty of the Tang, Lou-
tao-tfong, who wras difaffecled to the government, be¬
ing accufed of a fault, which touched his life, obtain¬
ed leave from thofe who had him in cuftody, to per¬
form the duties of the Tao to one of his deceafed
friends. He managed matters fo well, that giving his
keepers the flip, he fled to the houfe of Lou Nan-kin,
with whom he had a friendftiip, and these hid himfelf.
Lou Nan-kin, notwithftanding the Ariel fearch that
was made, and the feverity of the court againft thofe
who conceal prifoners that have efcaped, wmuld not
betray his friend. However, the thing coming to be
difeovered, Lou Nan-kin was imprifoned; and they
were juft on the point of proceeding againft him, when
his younger brother prefenting himfelf before the judge.
It is /, Sir, faid he, who have hidden the prifoner; it is
I who ought to die, and not my elder brother. The eldeft
maintained, on the contrary, that his younger brother ac¬
cufed himfelf wrongfully, aad was not at all culpable.
The judge, who was a perfon of great fagacity, fifted
both parties fo effe&ually, that he not only difeovered
that the younger brother was innocent, but even made
him confefs it himfelf: It is true, Sir, faid the younger
all in tears, I have accufed myfelf falfely; but I have
very frong reafons for fo doing. My mother has been
dead for fome time, and her corpfe is not yet buried; 1
have a fifer alfo who is marriageable, hut is not yet dif-
pofed of: thefe things which my brother is capable of ma¬
naging, I am not, and therefore defire to die in hisjlead.
Vouchfafe to admit my tefimony. The commiflioner gave
an account of the whole affair to the court, and the em¬
peror at his folicitation pardoned the criminal.”
PIG, fee Sus, 1 ]\fAMMALIA Iut/ex.
Guinea-PlG, fee Mus, j
PIG of lead, the eighth part of a fother, amounting
to 250 pounds rveight.
PIGANIOL de la Force, John Aymar de, a
native of Auvergne, of a noble family, applied himfelf
with ardour to the ftudy of geography and of the bi-
ftory of France. With the view of improving himfelf
in this ftudy, he travelled into different provinces ; and,
in the courfe ©f his travels, made fome important obfer-
vations on the natural hiftory, the commerce, the civil
and ecclefiaftical government of each province. Thefe ob-
fervations were of great ufe to him in compiling the works
he has left behind him, of which the chief are, I. An
Hiftorical and Geographical Defeription of France ; the
largeft edition of which is that of 1753, in 15 vols. i2mo.
It is the beft work which has hitherto appeared upon that
fubjedt, though it contains a great number of inaccura¬
cies and even errors. 2. A Defeription of Paris, in 10
vols. 12mo a work equally entertaining and inftruftive,
and much more complete than the defeription given by
Germain Brice : befides, it is written with an elegant
fimplicity. He publiftied an abridgement of it in 2 vols.
121110.
P i G [ 547 ] P I G
Pigeon. 12mo. 3. A Defcription of the Caltle and Park of Ver-
failles, Marly, &c. in 2 vols. l2mo: it is very amufing,
and pretty well executed. Piganiol had alfo a concern
with Abbe Nadal in the journal of Trevoux. He died
at Paris in February 1753, at ths age of 80 years. This
learned man was as much to be refpetled for his manners
as for his talents. To a profound and varied knowledge
he united great probity and honour, and all the polite-
nefs of a courtier.
PIGEON, fee Columba, Ornithology Index.
PlGEON-Houfe is a houfe erefted full of holes within,
for the keeping, breeding, &c. of pigeons, otherwife cal¬
led a dove-cot.
Any lord of manor may build a pigeon-houfe on
his land, but a tenant cannot do it without the lord’s
licence. When perfo-ns fhoot at or kill pigeons within
a certain dirtance of the pigeon-houfe, they are liable
to pay a forfeiture.
In order to ere£t a pigeon-houfe to advantage, it
will be neceffary, in the firft place, to pitch upon a
convenient fituation; of which none is more proper
than the middle of a fpacious court-yard, becaufe pi¬
geons are naturally of a timorous difpofition, and the
leaf! noife they hear frightens them. With regard to
the fize of the pigeon-houfe, it mull depend entirely
upon the number of birds intended to be kept} but it
is better to have it too large than too little j and as to
its form, the round Ihould be preferred to the fquare
ones ; becaufe rats cannot fo ealily come at them in
the former as in the latter. It is alfo much more
commodious •, becaufe you may, by means of a lad¬
der turning upon an axis, ealily vifit all the nelfs in
the houfe, without the leal! difficulty 5 which can¬
not fo ealily be done in a fquare houfe. In order to
hinder rats from climbing up the outfide of the pi¬
geon-houfe, the wall ffiould be covered with tin
plates to a certain height, about a foot and a half
will be fufficient j but they ffiould project out three or
four inches at the top, to prevent their clambering any
higher. v
The pigeon-houfe ffiould be placed at no great di-
ftance from water, that the pigeons may carry k to
their young ones *, and their carrying it in their bills
will warm it, and render it more wholefome in cold
weather. The boards that cover the pigeon-houfe
ffiould be well joined together, fo that no rain may
penetrate through it : and the whole building ffiould
be covered with hard plafter, and white-waffied within
and without, white being the moll plealing colour to
pigeons. There mult be no window, or other open¬
ing in the pigeon-houfe to the eallward j thefe ffiould
always face the fouth, for pigeons are very fond of the
fun, efpecially in winter.
The nefts or covers in a pigeon-houfe ffiould conffil of
fquare holes made in the walls, of a fize fufficient to ad¬
mit the cock and hen to ftand in them. The firft range
of thefe nefts ffi«uld not be lefs than four feet from the
ground, that the wall underneath being fmooth, the rats
may not be able to reach them. Thefe nefts ffiould be
placed in quincunx order, and not dire&ly over one an¬
other. Nor muft they be continued any higher than
within three feet of the top of the wall: and the upper
row ffieuld be covered with a board projefting a confi-
derable diftance from the wall, for fear the rats ffiould
find means to climb the outfide of the houfe.
M. Duhamei thinks that pigeons neither feed upon Pigeon,
the green corn, nor have bills ftrong enough to fearch
for its feeds in the earth } but only pick up the grains
that are not covered, which would infallibly become
the prey of other animals, or be dried up by the fun.
“ From the time of-the fprouting of the corn, fays he,
pigeons live chiefly upon the feeds of wild uncultivated
plants, and therefore leffen confiderably the quantity of
weeds that would otherwife fpring up j as will appear
from a juft eftimate of the quantity of grain neceflary to
feed all the pigeons of a ■well-ftocked dove-houfe.” But
Mr Worlidge and Mr Lille allege fads in fupport of the
contrary opinion. The latter relates, that a farmer in
his neighbourhood aflured him he had known an acre
fowed with peafe, and rain coming on fo that they could
not be harrowed in, every pea was fetched away in half
a day’s time by pigeons : and the former fays, “ It is to
be obferved, that where the flight of pigeons falls, there
they fill themfelves and away, and return again where
they firft rofe, and fo proceed over a whole piece of
ground, if they like it. Although you cannot perceive
any grain above the ground, they know how to find it.
I have feen them lie fo much upon a piece of about two
or three acres fown with peafe, that they devoured at
leaft three parts in four of the feed, which, I am fure,
could not be all above the furface of the ground. That
their fmelling is their principal diredor, I have obfer¬
ved j having fown a fmall plat of peafe in my garden,
near a pigeon-houfe, and covered them fo well that not
a pea appeared above ground. In a few days, a parcel
of pigeons were hard at work in difcovering this hidden
treafure; and in a few days more I had not above two
or three peas left out of about two quarts that were
planted ; for what they could not find before, they found
when the buds appeared, notwithftanding they were hoed
in, and well covered. Their fmelling alone direded
them, as I fuppofed, becaufe they followed the ranges
exadly. The injury they do at harveft on the peafe,
vetches, &c. is fuch that we may rank them among the
greateft eqemies the poor huffiandman meets withal; and
the greater, becaufe he may not ered a pigeon-houfe,
whereby to have a ffiare of his own fpoils ; none but the
rich being allowed this privilege, and fo fevere a law
being alfo made to proted thefe winged thieves, that a
man cannot encounter them, even in defence of his own
property. You have therefore no remedy againrt them,
but to affright them away by noifes or fuch like. You
may, indeed, ffioot at them; but you muft not kill
them ; or you may, if you can, take them in a net, cut
off their tails, and let them go \ by which means you
will impound them : for when they are in their houfes,
they cannot bolt or fly out of the tops of them, but by
the ftrength of their tails ; after the thus weakening of
which, they remain prifoners at home.”
Mr Worlidge’s impounding the pigeons reminds us of
a humorous ftory of a gentleman, who, upon a neigh¬
bouring farmer’s complaining to him, that his pigeons
were a great nuifance to his land, and did fad mifehief
to his corn, replied jokingly, Pound them, if you catch
them trefpaffing. The farmer, improving the hint,
fteeped a parcel of peafe in an infufion of cocu/us indicus, ‘
or fome other intoxicating drug, and ftrew’ed them upon
his grounds. The pigeons fwallowed them, and foon
remained motionlefs on the field : upon which the farm¬
er threw a net over them, inclofed them in it, and car-
• 3Z2 f ried
PIG t 548 ] PIG
Higfon. ried them to an empty barn, from whence he fent the
—' gentleman word that he had followed his directions with
regard to the pounding of his pigeons, and deiired him
to come and releafe them.
Carrier-P 1GEON. See CARRIER-Pigeon and CoLUM-
ba, Ornithology Index.
Pigeon, Peter Charles Francis, curate of St Peter
du Regard, in the diocefe of Bayeux, was one of the
priefts lately belonging to the king’s houfe at Winche-
iter. He was born in Lower Normandy, of honeft and
virtuous parents, and of a decent fortune. His inclina-
, tions early led him to embrace the ecclefiaftical Rate,
from which neither the felicitations of his friends, nor
the profpeCl of a more ample fortune on the death of his
elder brother, could withdraw him. Several of his
fchoolfellows and mailers, who are now reiident in the
king’s houfe at Wincheiler, bear the moil ample teili-
mony to his affiduity, regularity, piety, and the fweet-
nefs of his difpoiition, during the whole courfe of his
education. The fweetnefs of temper, in particular, was
fo remarkable, and fo clearly depicted on his counte¬
nance, as to have gained him the efteem and affeCtion of
fuch of the inhabitants of Wincheiler as by any means
had become acquainted with him. Pie v7as feven years
employed in quality of vicar, or, as wre ihould call it,
curate, of a large parifh in the diocefe of Seez, where
his virtues and talents had ample fcope for exertion. His
praClice wras to rife at five o’clock every morning, and
to fpend the whole time till noon (the ufual time of din¬
ing for perfons in his Ration) in prayer and Rudy. The
reR of the day, till evening, he devoted to vifiting the
fick, and other exterior duties of his funCtion. In 17 89,
the year of the French revolution, M. Pigeon was pro¬
moted to a curacy, or rather a reCtory, in the diocefe of
Bayeux, called the pari/h of St Peter du Regard, near
the town of Conde fur Noereau. It was eafy for him to
gain the good-will and the protection of his parifhion-
ers} but a Jacobin club in the above-mentioned town
feemed to have no other lubjeCt to deliberate upon than
the various ways of harafling and perfecuting M. Pigeon
, and certain other priefls in the neighbourhood, who had
from motives of confcience refufed the famous civic oath.
It would be tedious to relate the many cruelties which
w'ere at different times exercifed upon him, and the im¬
minent danger of lofing his life to which he was expo-
fed, by the blows that were inflicted on him, by his be¬
ing thrown into wTater, and being obliged to wander in
w-oods and other folitary places, without any food or
place to lay his head, in order to avoid his perlecutors.
We may form fome judgement of the fpirit of his perfe-
cutors from the following circumflance. Being difap-
pointed on a particular occafion in the fearch they w'ere
making after M. Pigeon, with the view of amufing
themfelves with his fufferings, they made themfelves a-
mends by feizing his mother, a refpeCtable lady of 74
years of age, and his tvro fiflers, whom they placed up¬
on affes with their faces turned backwards, obliging them
in derifion to hold the tails of thefe animals. Thus they
were conduCted in pain and ignominy throughout the
whole town of Conde, for no other alleged crime ex-
* cept being the nearefl relations of M. Pigeon. At
length the decree for tranfporting all the ecclefiaflics ar¬
rived ; and this gentleman, with feveral others, after
having been flripped of all their money, -was Riipped
from Port Beflin, and landed at Pcrtfmouth, where he
was fliortly after received into the eflablhhment at Fox- Pigeon
ton, and, upon that being diffolved in order to make il
room for prifoners of war, into the king’s houfe at Win-,
cheRer. Being of a Rudious turn, he was accuflomed, " v
as many of his brethren alfo were, to betake himfelf to
the neighbouring lanes and thickets for the fake of
greater folitude. With this viewr having, about ten
o’clock in the morning, Aug. 28. 1793, retired to a
certain little valley, on the north-eaR fide of a place
called Orarn’s Arbour, the fame place where the county
elections for Hamplhire are held, he was there found,
between three and four o’clock in the afternoon, mur¬
dered, with the upper part of his fkull abfolutely broken
from the lower part, and a large hedge-flake, covered
wuth blood, lying by him, as were the papers on wThich
he had been tranferibing a manufeript fermon, with the
hearing of wThich he had been much edified, and the fer¬
mon itfelf w'hich he w7as copying, together with his pen,
imbrued in blood. His wTatch was carried aw?ay, though
part of the chain, which had by fome means been bro¬
ken, wras left behind. He was wniting the word para-
dife, the lafl letters of winch remained unwritten when
the fatal blow w7as given him, which appears evidently
to have been difeharged upon him from a gap in a
hedge which w7as immediately behind him. At firfl the
fufpicion of this cruel murder fell upon the French de¬
mocrats, wiro, to the number of 200, are prifoners of
wrar, at the neighbouring tow7n of Alresford, as one of
that number, who had broken his parole, had, about
three weeks before, been taken up in Winchefler, and
both there and at Alresford had repeatedly threatened
to murder his uncle, a priefl, whom he undevflood to be
then at Winchefler, not without fervent wiflies of hav¬
ing it in his power to murder the whole eflabliflynent,
confiding of more than 600 perfons. PIow7ever, as no
French prifoner was feen that day in the neighbourhood
of Winchefler, as none of them w7ere know n to have
left Alresford, it is evidently reafonable to acquiefce in
the verdict of the coroner j namely, that the murder
wras committed by a per'fon or perfons unknown. The
mod noble marquis of Buckingham, whofe munificence
and kindnefs to thofe confcientious exiles, the emigrant
French clergy, can only be conceived by thofe who
have been witneffes of the fame, with the truly refpeft-
able corps of the Bnckinghamfliire militia, then quar¬
tered at WincheRer, joined in paying the laff mark of
refpect to the unfortunate deceafed, by attending his fu¬
neral, which was performed at the Roman Catholic bu-
rying-ground, called St James'ls, near the faid city, on
Saturday, Aug. 29. He was juR 38 years of age when
he was murdered.
PIGMENTS, preparations ufed by painters, dyers,
&c. to impart colours to bodies, or to imitate particular-
colours. See COLOUR-Mahing, and Dyeing.
PIGNEROL is a towm of Italy in the province of
Piedmont, in E. Long. 7. 15. N. Lat. 44. 45. fituated
on the river Chizon, 10 miles fouth-weff of Turin, at
the foot of the Alps, and the confines of Dauphiny.
The towm is fmall, but populous, and extremely well
fortified by the king of Sardinia, fince the treaty of U-
trecht. It is defended by a citadel, on the top of the
mountain near which is the caflle of Peroufe, which
wras built at the entrance of the valley of that name.
PIGNUT, or Eartlinut. See Bunium, Botany
Index.
PIG US.
V 1 K
F;gus PIGUS, in Ichilnjology, is the name of a fpecies of
Pike leather-mouthed fifh, very much refembling the nature
_ * ' i of the common carp \ being of the fame ihape and fize,
and its eyes, fins, and fiefhy palate, exadtly the fame j
from the gills to the tail there is a crooked dotted line j
the back and fides are bluifh, and the belly reddilh. It
is covered with large fcales ; from the middle of each of
which there rifes a fine pellucid prickle, which is very
(harp. It is an excellent filh for the table, being per¬
haps preferable to the carp 5 and it is in feafon in the
months of March and April. It is caught in lakes in
fome parts of Italy, and is mentioned by Pliny, though
without a name. Artedi fays it is a fpecies of eyprinus,
and he calls it the cyprinus, called piclo and pig us.
PI-HAHIROTH, (Mofes) *, underftood to be a
mouth or narrow pafs between two mountains, called
Chiroth, or Eiroth, and lying not far from the bottom
of the weftern coaft of the Arabian gulf; before which
mouth the children of Ifrael encamped, juft before their
entering the Red fea, (Wells).
PIISSKER, in Ichthyology, is a fiih of the muftela
kind, commonly called the fojfile mujlela, or fojfde JiJh.
This fifh is generally found as long as an ordinary man’s
hand is broad, and as thick as the finger; but it
fometimes grows much longer : the back is of gray with
a number of fpots and tranfverfe ftreaks, partly black
and partly blue; the belly is yellow, and fpotted with
red, white, and black j the wdiite are the larger, the
others look as if they were made with the point of a
needle ; and there is on each of the fides a longitudinal
black and white line. There are fome flefhy excrefcen-
ces at the mouth, which are expanded in fwimming *,
and when out of the water, they are contrafted. Thefe
fifhes run into caverns of the earth, in the fides of ri¬
vers, in marfhy places, and penetrate a great way, and
are often dug up at a diftance from waters. Often,
when the waters of brooks and rivers fwell beyond
their banks, and again cover them, they make their
way out of the earth into the water 5 and when it de-
fcrts them, they are often left in vaft numbers upon the
ground, and become a prey to fwine. It is thought to
be much of the fame kind with the fifgum filh \ and it
is indeed poffible that the paecilia of Schonefeldt is the
lame.
PIKE. See Esox, Ichthyology Index.
The pike never fwims in fhoals as moft other fifh do,
but always lies alone} and is fo bold and ravenous, that
he will feize upon almofl any thing lefs than himfelf. Of
the ravenous nature of this filh we fhall give the follow¬
ing inllances. At Rycott in Oxfordlhire, in the year
1749, a moat furrounding the earl of Abingdon’s
feat, there was a jack or pike of fuch a monftrous fize,
that it had defiroyed young fwans feathers and all. An
old cobb fvvan having hatched five young, one after an¬
other was loft till four were gone. At length an under
gardener faw the filh feize the fifth. The old one
fought him with their beak, and with the aftiftance of
the gardener, releafed it although he had got it under
water. Inthayear 1765 a large pike was caught in
the river Ouze, which weighed upwards of 28 pounds,
and was fold for a guinea. On gutting the filh, a
watch with a black ribbon and two fteel feals w?ere found
in its ftomach, which, by the maker’s name, &c. was
found to belong to a perfon wrho had been drowned a-
bout fix weeks before. This filh breeds but once in a
P I K
year, which is in March. It is found in almoft all frelh
wraters; but is very different in goodnefs, according to
the nature of the places where it lives. The fineft pike
are thofe which feed in clear rivers thofe in ponds and
meres are inferior, and the worft of all are thofe of
the fen ditches. They are very plentiful in thefe laft
places, where the water is foul and coloured, and their
food, luch as frogs and the like, very plentiful, but ve¬
ry coarfe 5 fo that they gixw large, but are yellowilh
and high bellied, and differ greatly from thole which
live in the clearer waters.
The filhermen have twm principal wrays of catching
the pike; by the ledger, and by the wralking-bait.
The ledger-bait is fixed in one certain place, and may
continue while the angler is abfent. This mull be a
live bait, a filh or frog : and among filh, the dace,
roach, and gudgeon, are the belt; of frogs, the only
caution is to choofe the largeft and yelloweft that can be
met with. If the bait be a filh, the hook is to be ftuck
through the upper lip, and the line mull be 14 yards at
leaft in length 5 the other end of this is to be tied to a
bough of a tree, or to a flick driven into the ground
near the pike’s haunt, and all the line wound round a
forked ftick, except about half a yard. The bait will
by this means keep playing fo much under water, and
the pike will foon lay hold of it.
If the bait be a frog, then the arming wire of the-
hook Ihould be put in at the mouth, and out at the fide 5
and with a needle and fome ftrong filk, the hinder leg of
one fide is to be faftened by one flitch to the ware-arm¬
ing of the hook. The pike will foon feize this, and muff
have line enough to give him leave to get to his haunt
and poach the bait.
The trolling for pike is a pleafant method alfo of tak¬
ing them : in this a dead bait ferves, and none is fo pro¬
per as a gudgeon.
This is to be pulled about in the water till the pike
feizes it; and then it is to have line enough, and time
to fwallow it: the hook is fmall for this fport, and has
a fmooth piece of lead fixed at its end to link the bait;
and the line is very long, and runs through a ring at
the end of the rod, which muft not be too flender at
top.
The art of feeding pike, fo as to make them very fat,
is the giving them eels ; and without this it is not to be
done under a very long time ; otherwife perch, while
fmall, and their prickly fins tender, are the beft food for
them. Bream put into a pike-pond are a very proper
food : they wall breed freely, and their young ones make
excellent food for the pike, who wall take care that they
fhall not increafe over much. The numerous fhoals of
roaches and ruds, which are continually changing place,
and often in Hoods get into the pike’s quarters, are food
for them for a long time.
Pike, when ufed to be fed by hand, will come up to
the very fhore, and take the food that is given them out
of the fingers of the feeder. It is wonderful to fee with
what courage they will do this, after a while pra&ifing;
and it is a very diverting fight when there are feveral of
them nearly of the fame fize, to lee what ftriving and-
fighting there wall be for the beft bits when they are
thrown in. The moft convenient place is near the
mouth of the pond, and where there is about half a yard
depth of water ) for, by that means, the offal of the-
feedings will all lie in one place, and the deep water.
will
1 549 1
P I L t 55° ] P I L
will ferve tor a place to retire into and reft in, and will
be always clean and in order.
Carp may be fed in the fame manner as pike *, and
though by nature a fiftt as remarkably ftiy and timorous
as the pike is bold and fearlefs, yet by cuftom they will
come to take their food out of the perfon’s hand ; and
will, like the pike, quarrel among one another for the
niceft bits.
Pike, in War, an offenfive weapon, confifting of a
wooden {haft, 12 or 14 feet long, with a flat fteel head,
pointed, called the f/>ear. This weapon was long in
ufe among the infantry $ but now the bayonet, which is
fixed on the muzzle of the firelock, is fubftituted in its
ftead. It is ftill ufed by fome of the officers of infantry,
under the name of fhonttfn. The Macedonian phalanx
was a battalion of pikemen. See Phalanx.
PILA marina, or the fea-ball, in Natural Hiftory,
is the name of a fubftance very common on the fhores of
the Mediterranean, and elfewhere. It is generally found
in the form of a ball about the fize of the balls of horfe
dung, and compofed of a variety of fibrillae irregularly
complicated. Various conjectures have been given of
its origin by different authors. John Bauhine tells us,
that it confifts of fmall hairy fibres and ftraws, fuch as
are found about the fea plant called a/ga vitrianorum ;
but he does not afcertain vvhat plant it owes its origin
to. Imperatus imagined it confifted of the exuvite both
of vegetable and animal bodies. Mercatus is doubtful
whether it be a congeries of the fibrillae. of plants, wound
up into a ball by the motion of the fea water, or whe¬
ther it be not the workmanflup of fome fort of beetle
living about the fea fhore, and analogous to our common
dung beetle’s ball, which it elaborates from dung for
the reception of its progeny. Schreckius fays it is com¬
pofed of the filaments of fome plant of the reed kind :
and Welchius fuppofes it is compoled of the pappous
part of the flowers of the reed. Maurice Ploftman
thinks it the excrement of the hippopotamus} and others
think it that of the phoca or fea calf. Klein, who had
thoroughly and minutely examined the bodies them-
felves, and alfo what authors had conjectured concern¬
ing them, thinks that they are wholly owing to, and
entirely compofed of, the capillaments w'hich the leaves,
growing to the woody ftalk of the alga vitriariorum,
have wrhen they wither and decay. Thefe leaves, in
their natural ftate, are as thick as a wheat ftraw, and
they are placed fo thick about the tops and extremities
of the ftalks, that they enfold, embrace, and lie over
one another and from the middle of thefe clufters of
leaves, and indeed from the woody fubftance of the
plant itfelf, there arife feveral other very long, flat,
fmooth, and brittle leaves. Thefe are ufually four from
each tuft of the other leaves*, and they have ever a
common vagina, wffiich is membranaceous and very thin.
This is the ftyle of the plant, and the pila ??iarina ap¬
pears to be a clufter of the fibres of the leaves of this
plant, which cover the whole ftalk, divided into their
conflituent fibres *, and by the motion of the v,raves firft
broken and worn into fhort fhreds, and afterwards
wound up together into a roundilh or longifli ball.
Pila, was a ball made in a different manner accord¬
ing to the different games in which it was to be ufed.
Playing at ball was very common amongft the Romans
of the firft diftindlion, and was looked upon as a manly
exercife, which contributed both to amufement and
3
health. The pila was of four forts : ift, Follis oxbal- Pua
loon; 2d, Pila Trigonalis; 3d, Pila Paganica; 4th, I!
Harpajium. All thefe come under the general name of, *1 ,
pila. For the manner of playing with each of them, fee
the articles Follis, Trigonalis.
PILASTER, in Architecture. See there, N° 50,
&c.
PILATE, or Pontius Pilate, was governor of Ju¬
dea when our Lord was crucified. Of his family or
country we know but little, though it is believed that
he was of Rome, or at leaft of Italy. He was fent to
govern Judea in the room of Gratus, in the year 26 or
27 of the vulgar era, and governed this province for
ten years, from the 1 2th or 13th year of Tiberius to the
22d or 23d. Fie is reprefented both by Philo and Jofe-
phus as a man of an impetuous and obftinate temper, and
as a judge who ufed to fell juftice, and to pronounce any
fentence that was defired, provided he was paid for it.
The fame authors make mention of his rapines, his inju¬
ries, his murders, the torments that he inflifted upon
the innocent, and the perfons he put to death without
any form of procefs. Philo, in particular, defcribes him
as a man that exercifed an exceffive cruelty during the
whole time of his government, who difturbed the repofe
of Judea, and gave occafion to the troubles and revolt
that followed after. St Luke (xiii. 1, 2, &c.) acquaints
us, that Pilate had mingled the blood of the Galileans
with their facrifices; and that the matter having been
related to Jefas Chrift, he faid, “ Think you that thefe
Galileans were greater finners than other Galileans, be-
caufe they fuffered this calamity. I tell you nay ; and
if you do not repent, you (hall all periflr in like manner.”
It is unknown upon what occafion Pilate caufed thefe
Galileans to be (lain in the temple while they wTere facri-
ficing ; for this is the meaning of that expreffion of
mingling their blood with their facrifices. Some think
they were difciples of Judas the Gaulonite, who taught
that the Jews ought not to pay tribute to foreign princes j
and that Pilate had put fome of them to death even in
the temple *, but there is no proof of this faft. Others
think that thefe Galileans were Samaritans, whom Pilate
cut to pieces in the village of Tirataba f, as they were f Jofeph.
preparing to go up to Mount Gerizim, where a certain A7itiq. lib,
impoftor had promifed to difcover treafures to them ; but xv“1* c* S*
this event did not happen before the year 35 of the com¬
mon era, and confequently two years after the death of
Jefus Chrift. At the time of our Saviour’s paffion, Pi¬
late made fome endeavours to deliver him out of the
hands of the Jews. He knew they had delivered him
up, and purfued his life with fo much violence, only out
of malice and envy (Matt, xxvii. 18.). His wife alfo,
who had been difturbed the night before with frightful
dreams, fent to tell him flie defired him not to meddle
in the affair of that juft perfon (ib. 19.). He attempted
to appeafe the wrath of the Jews, and to give them fome
fatisfattion, by whipping Jefus Chrift (John xix. 1.
Matth. xxvii. 26.). He tried to take him out of their
hands, by propofing to deliver him or Barabbas, on the
day of the feftival of the paffover. Laftly, he had a
mind to difcharge himfelf from pronouncing judgement
againft him, by fending him to Herod king of Galilee
(Luke xxiii. 7, 8.). When he faw all this would not
fatisfy the Jews, and that they even threatened him in
fome manner, faying he could be no friend to the em¬
peror if he let him go (John xix. 12, 15.), he caufed
water
Pilate.
< v—
p 1 L t 55i 1 P I L
water to be brought, wafhed his hands before all the
people, and publicly declared himfelf innocent of the
blood of that juft perfon (Matt, xxvii. 23, 24.) j yet at
the fame time he delivered him up to his foldiers, that
they might crucify him. This was enough to juftify Je-
fus Chrift, as Calmet obferves, and to (how that he held
him as innocent; but it was not enough to vindicate the
confcience and integrity of a judge, whofe duty it was
as well to affert the caufe of oppreffed innocence as to
punilh the guilty and criminal. He ordered to bp put
over our Saviour’s crofs, as it were, an abftradb of his
fentence, and the motive of his condemnation (John
xix. 9.), Jefus of Nazareth, king of the Jews, which
was written in Latin, Greek, and Hebrew. Some of
the Jews found fault with it, and remonftrated to Pilate
that he ought to have written Jefus of Nazareth, who
pretended to he king of the Jews. But Pilate could
not be prevailed with to alter it, and gave them this
peremptory anfwer, That what he had written he had
written.
Towards evening, he was applied to for leave to take
down the bodies from the crofs, that they might not
continue there the following day, which w-as the paflb-
ver and the fabbath-day (John xix. 31.). This he al¬
lowed, and granted the body of Jefus to Jofeph of Ari-
mathea, that he might pay his laft duties to it, (ib. 33.).
Laftly, when the priefts, who had folicited the death of
our Saviour, came to defire him to fet a watch about
the fepulchre, for fear his difciples ftiould Ideal him away
by night, he anfwered them, that they had a guard, and
might place them there themfelves (Matt, xxvii. 6 ^.),
This is the fubftance of what the gofpel tells us con¬
cerning Pilate.
Juftin Martyr, Tertullian, Eufebius, and after them
feveral others both ancient and modern, affure us, that
it was formerly the cuftom for Roman magiftrates to
prepare copies of all verbal proceffes ^nd judicial a&s
which they paffed in their feveral provinces, and to
lend them to the emperor. And Pilate, in compliance
to this cuftom, having fent word to Tiberius of what
had palled relating to Jefus Chrift, the emperor wrote
an account of it to the fenate, in a-manner that gave
reafon to judge that he thought favourably of the re¬
ligion of Jefus Chrift, and fhowed that he ftiould be wil¬
ling they would decree divine honours to him. But the
ienate was not of the fame opinion, and fo the matter
was dropped. It appears by what Juftin fays of thefe
adds, that the miracles of Jefus Chrift were mentioned
there, and even that the loldiers had divided his garments
among them. Eufebius infinuates that they fpoke of his
refurredlion and afeenfion. Tertullian and Juftin refer
to thefe ads with fo much confidence as would make
one believe they had them in their hands. However,
neither Eufebius nor St Jerome, who were both inqui-
fitive, underftanding perfons, nor any other author that
wrote afterwards, feem to have feen them, at leaft not
the true and original ads 5 for as to what we have
now in great number, they are not authentic, being nei¬
ther ancient nor uniform. There are alfo fome pretend¬
ed letters of Pilate to Tiberius, giving a hiftory of our
Saviour, but they are univerfally allowed to be fpurious.
Pilate being a man that, by his exceflive cruelties
and rapine, had difturbed the peace of Judea during
tne whole time of his government, was at length de-
pmed by Vitellius the proconful of Syria, in the 36th
year of Jefus Chrift, aiid fent to Rome to give an ae- Piiate
count of his condud to the emperor. But though Ti- II
berius died before Pilate arrived at Rome, yet his fuc- ,Fllchard-,
celTor Caligula banifhed him to Vienne in Gaul, where '
he was reduced to fuch extremity that he killed himfelf
with his own hands. Ihe evangelifts call him governor,
though in reality he was no more than procurator of
Judea, not only becaufe governor was a name of gene¬
ral ule, but becaufe Pilate in effed aded as one, bv
taking upon him to judge in criminal matters ; as his
piedeceilors had done, and other procurators in the
Imall provinces of the empire w7here there was no pro-
comul, conftantiy did. See CafmePs Didiionary, Ec-
hard's Ecclefiajlical DiEhonary, and Bcaufobre',s Annot.
. ^ ^ regard to Pilate’s wife, the general tradition
is, that the was named Claudia Procula or Prolcula j
atH in relation to her dream, fome are of opinion that
as the had intelligence of our Lord’s apprehenfion, and
knew by his charader that he was a righteous perfon,
hei imagination, being ftruck with thefe ideas, did na-
tuially pioduce the dream we read of 5 but others think
tnat this dream^ was fent providentially upon her, for
trw clearer mamfeftation of our Lord’s innocence.
PI L AT RE du Rozier, Francis, was born at Metz
tne 30th of March He wras firft apprentice to
an apothecary there, and afterwards went to Paris in
queft of farther improvement. He applied himfelf to
the ftudy of natural hiftory and of natural philofophy,
and had already acquired fome reputation, when the dif-
covery of M. de Montgolfier had juft aftonilhed the
learned wmrld. _ On the 25th of Odober 1783, he at¬
tempted an aerial voyage with the Marquis of Arlande.
He performed feveral other excurfions in this way with
biilnant fucceis, in the prefence of the royal family of
France, of the king of Sweden, and of Prince Henry of
Pruflia. He then refolved to pafs into England by
means of his aerial vehicle, and for that purpoie he re¬
paired to Boulogne, whence he rofe about 7 o’clock in
the morning of the 15th June 1785 ; but in half an hour
a ter he fet. cut, the balloon took fire, and the aero¬
naut, with his companion M. Romaine, were cruftied to
death by the fall of that machine, which was more in¬
genious, perhaps, than ufeful *. Pilatre’s focial virtues * 9- 4
and courage which were very diftinguiftied, heightened/?^*
the regret of his friends for his lot's. His merit as a N° 3^’
chemift, and his experiments as an aeronaut, procured
him fome pecuniary reward, and fome public appoint¬
ments. He had a pennon from the king, was intendant
of Monfieur’s cabinets of natural philofophy, chemiftrv
and natural hiftory, profeffor of natural philofophy,'a
member or feveral academies, and principal diredor of
Monfieur’s mufeum.
PILCHARD, in Ichthyology, a fifh which has a gene¬
ral relemblance to the herring, but differs in fome effential
particulars. The body of the pilchard is lefs compreffed
than that of the herring, being thicker and rounder : the
nofe. is fhorter in proportion, and turns up ; the under
jaw is ftiorter. The back is more elevated ; the belly
lefs (harp. Jhe dorfal fin of the pilchard is placed
exadly in the centre of gravity, fo that when taken up
by it, the body preferves an equilibrium, whereas that
of the herring dips at the head. The feales of the pil¬
chard adhere very clofely, whereas thofe of the herrina
very eafily drop off. The pilchard is in general lefts
than the herring 5 but it is fatter, or more full of oil.
The
p 1 L C 55
Pilchard, The pilchard appears in vaft (lioals off the Cornifh
1J|!c' , coafts about the middle of July, difappearing the be¬
ginning of winter, yet fomelimes a few return again
after Chriftmas. Their winter retreat is the fame with
that of the herring, and their motives for migrating
t See Clu~ the fame f. They affedf, during fummer, a warmer la-
titude ; for they are not found in any quantities on
any of our coafts except thofe of Cornwall, that is to
fay, from Fowey harbour to the Scilly ifles, between
which places the fhoals keep ftiifting for fome weeks.
The approach of the pilchard is known by much the
fame figns as thofe that indicate the arrival of the her¬
ring. Perfons, called in Cornwall huers, are placed on
the cliffs, to point to the boats ftationed off the land
the courfe of the fifti. Ey the ill of James I. c. 23.
fifhermen are empowered to go on the grounds of others
to hue, without being liable to adHons of trefpdfs, which
before occafioned frequent law-fuits.
' The emoluments that accrue to the inhabitants of
that country are great, and are belt exprefled in the
words of Dr W. Borlafe, in his Account of the Pil¬
chard Fifhery. “ It employs a great number of men
on the fea, training them thereby to naval affairs} em¬
ploys men, women, and children, at land, in halting,
prefting, walking, and cleaning, in making boats, nets,
ropes, calks, and all the trades depending on their con-
ftrudlion and fale. The poor is fed with the offals of
the captures ; the land with the refufe of the fdh and
fait ; the merchant finds the gains of commiftion and
honeft commerce 5 the filherman, the gains of the fifti.
.Ships are often freighted hither with fait, and into fo¬
reign countries with the fifti, carrying off at the fame
time part of our tin. The ufual number of hogiheads
of filh exported each year, for 10 years, from 1747 to
1756 inclufive, from the four ports of Fowey, Falmouth,
Penzance, and St Ives, in all amounts to 29,794 ; fince
it appears that Fowey has exported yearly 173 2 hogf*
heads j Falmouth, 14,631 hogiheads and two-thirds *,
Penzance and Mounts-Bay, 12,149 hogiheads and one-
third 5 Stives, 1282 hoglheads. Every hogftiead for
ten years laft paft, together with the bounty allowed
for each when exported, and the oil made out of each,
has amounted, one year with another at an average,
to the price of il. 13s. 3d. ; fa that the calh paid for
pilchards exported has, at a medium, annually amount¬
ed to the fum of 49,532!. 10s.” The numbers
that are taken at one ftiooting out of the nets is ama¬
zingly great. Mr Pennant fays, that Dr Borlafe af-
fured him, that on the 5th of Oftober 1767, there
were at one time inclofed in St Ives’s bay 7000 hogf-
-heads, each hogftiead containing 35,000 fifti, in all
245,000,000.
PILE, in Hera/dnj, an ordinary in form of a wedge,
contrafting from the chief, and terminating in a point
towards the bottom of the Ihield.
Pile, among the Greeks and Romans, was a pyra¬
mid built of wood, whereon wTere laid the bodies of
the deceafed to be burnt. It was partly in the form
of an altar, and differed in height according to the
quality of the perfon to be confumed. Probably it
might originally be confidered as an altar, on which
the dead were confumed as a burnt offering to the in¬
fernal deities. The trees made ufe of in the erection of
a funeral pile were fuch as abounded in pitch or rofin,
as being moft combuftible ; if they ufed any other wood,
2 ] P I L
it was fplit that it might the more eafily catch fire. Plk*
Round the pile were placed cyprefs boughs to hinder thev”"'
noifome fmelL See Funeral.
Pile, in Building, is ufed for a large flake rammed
into the ground in the bottom of rivers, or in marftiy
land, for a foundation to build upon.
Pile is alfo ufed among architefts for a mafs of build-
ins- . . ’ .
Pile, in Coinage, denotes a kind of puncheon, which,
in the old way of coining with the hammer, contained
the arms or other figure and infeription to be ftruck on
the coin. See Coinage.
Accordingly we ftill call the arms fide of a piece of
money the pile, and the head the crofs; becaufe in an¬
cient coin, a crofs ufually took the place of the head in
ours.
PlLE-Engine, a very curious machine invented by piate
Mr Vauloue for driving the piles of Weftminfter-bridge.CGtC^IX.
A is a great upright ftiaft or axle, on which are the
great wheel B, and the drum C, turned by horfes joined
to the bars S, S. The wheel B turns the trundle X, on
the top of whofe axis is the fly O, which ferves to regu¬
late the motion, and alfo to aft againft the horfes, and
to keep them from falling when the heavy ram is dif-
charged to drive the pile P down into the mud in the
bottom of the river. The drum C is loofe upon the
ftiaft A, but is locked to the wheel B by the bolt Y.
On this drum the great rope HH is wound ; one end of
the rope being fixed to the drum, and the other to the
follower G, to which it is conveyed over the pulleys I
and K. In the follower G is contained the tongs' F,
that takes hold of the ram O by the ftaple R, for draw¬
ing it up. D is a fpiral or fufy fixed to the drum, on
which is wound the fmall rope T that goes over the
pulley U, under the pulley V, and is faftened to the
top of the frame at 7. To the pulley-block V is hung
the counterpoife W, which hinders the follower T from
accelerating as it goes down to take hold of the ram 5
for as the follower tends to acquire velocity in its defeent,
the line T winds downwards upon the fufy, on a larger
and larger radius, by which means the counterpoife W
afts ftronger and ftronger againft it ; and fo allows it
to come down with only a moderate and uniform velo¬
city. The bolt Y locks the drum to the great wheel,
being puftred upward by the fmall lever 2, which goes
through a mortife in the ftiaft A, turns upon a pin in
the bar 3, fixed to the great wheel B, and has a weight
4, which always tends to pufti up the bolt Y through
the wheel into the drum. L is the great lever turning
on the axis m, and refting upon the forcing bar 5, 5,
which goes through a hollow in the ftiaft A, and bears
up the little lever 2.
By the horfes going round, the great rope FI is
wound about the drum C, and the ram £) is drawn up
by the tongs F in the follower G, until the tongs come
between the inclined planes E ; which, by ftiutting the
tongs at the top, opens it at the foot, and difeharges
the ram which falls down between the gtudes hh 1 on
the pile P, and drives it by a few ftrokes as far into the
mud as it will go; after which, the top part is fawed
off clofe to the mud by an engine for that purpofe.
Immediately after the ram is difeharged, the piece 6
upon the follower G takes hold of the ropes a a, which
raife the end of the lever T m-d <wUfe its end N to de¬
scend and prefs down the forcing bar 5 upon the little
lever
Plate OC'CCXLX
Marhirte fo:r lioring1 wooden PIPKS.
P XL E Eng-ine .
4
P I L
lever 2, which, by pulling down the bolt Y, unlocks the
drum C from the great wheel B j and then the follow¬
er being at liberty, comes down by its own weight to
the ram and the lower ends of the tongs flip over the
ftaple R, and the weight of their heads caufes them to
fall outward, and (hut upon it. Then the weight 4
pulhes up the bolt Y into the drum, which locks it
to the great wheel, and fo the ram is drawn up as be¬
fore.
As the follower comes down, it caufes the drum to
turn backward, and unwinds the rope from it, whillt
the horfes, great wheel, trundle, and fly, go on with
an uninterrupted motion j and as the drum is turning
backward, the counte'rpoife W is drawn up, and its rope
T wound upon the fpiral fufy D.
There are feveral holes in the under fide of the drum,
and the bolt Y always takes the firfl: one that it finds
when the drum flops by the falling of the follower upon
the ram j until which ftoppage the bolt has not time to
flip into any of the holes.
This engine was placed upon a barge on the water,
and fo was eafily conveyed to any place defired. The
ram was a ton weight $ and the guides b b, by which it
was let fall, were 30 feet high.
A new machine for driving piles has been invented
by Mr Bunce of Kirby ftreet, Hatton ftreet, Loudon.
It will drive a greater number of piles in a given time
than any other \ and can be conftrufted more Amply to
work by horfes than Mr Vauloue’s engine above de-
fcribed.
Fig. I and 2 reprefent a fide and front fe&ion of the
machine. The chief parts are A, fig. 1, which are two
endlefs ropes, or chains, connected by crofs pieces of iron
B (fee fig. 2), correfponding with two crofs grooves cut
diametrically oppofite in the wheel C (fig. 1.), into
which they are received j and by which means the rope
or chain A is carried round. FHK is a fide-view of a
flrong wooden frame moveable on the axis H. D is a
wheel, over which the chain pafles and turns within at
the top of the frame. It moves occafionally from F
to G upon the centre H, and is kept in the pofition F
by the weight I fixed to the end K. Fig. 3. L is the
iron ram, which is connefted with the crofs pieces by
the hook M. N is a cylindrical piece of wood fufpended
at the hook at O, which by Aiding freely upon the bar
that connects the hook to the ram, always brings the ’
hook upright upon the chain when at the bottom of the
machine, in the pofition of GP. See fig. 1.
When the man at S turns the ufisal crane wmrk, the
ram being connected to the chain, and palling betw-een
the guides, is drawn up in a perpendicular dire£Hon ;
and wdien it is near the top of the machine, the pro-
jedling bar Q of the hook ftrikes againft a crofs piece of
wood at R (fig. 1.) ; and confequently difcharges the
ram, whilft the weight I of the moveable frame inftant-
ly draws the upper wheel into the pofition Ihown at F,
and keeps the chain free of the ram in its defcent. The
hook, wbile defcending, is prevented from catching the
chain by the wooden piece N. For that piece being
Vol. XVI. Part II.
P I L
fpecifically lighter than the iron weight below’, and
moving with a lefs degree of velocity, cannot come in
contaft with the iron till it is at the bottom and the ram
flops. It then falls and again connefts the hook with
the chain, which draw’s up the ram, as before.
Mr Bunce has made a model of this machine, which
perfoims perfectly well; and he obferves, that, as the
motion of the wheel C is uninterrupted, there appears to
be the leaft poflible time loll in the operation.
PILE-Worms, are a kind of worms found in the piles
of the fea-dikes in Holland. I hey are of very various
fizes 5 for fome of the young ones are not above an inch
or two in length, while others have been found thirteen
or fourteen inches long. The heads of thefe crea¬
tures are covered with tw’o hard (hells or hemicrania ;
which, together form a figure refembling an augre j
and wfith which they bore the wood. The beft reme¬
dy againft them is, to perforate the pile with many
fmall holes about an inch afunder j then it muft be
done over with a varnilh in the hotteft fun ; and, while
the varnilh is het, brick dull muft be ftrew’ed over it :
and this being feveral times repeated, the pile will be
covered with a ftrong cruft abfolutely impenetrable to
all infefls.
PILES, in Medicine, the fame with haemorrhoids.
See Medicine, N° 240, &c.
PILEUS, in Roman antiquity, w’as the ordinary cap
or hat W’orn at public Ihows and facrifices, and by the
freedmen. It was one of the common rewards afligned
to fuch gladiators as w’ere Haves, in token of their ob¬
taining freedom.
PILEWORT (RanunculusJicaria, Lin.), the root.
This is a very fmall plant, -found in moift meadows and
by hedge fides. The roots confift of (lender fibres with
fome little tubercles among them, which are fuppofed to
refemble the haemorrhoids. From thence it has been
concluded, that this root muft needs be of wonderful
efficacy for the cure of that diftemper : to the tafte, it
is little other than mucilaginous j and although ftill re¬
tained in feveral of the foreign pharmacopoeias, it is
hardly in ufe in this country.
PILGRIM, one wrho travels through foreign coun¬
tries to vifit holy places, and to pay his devotion to the
relicks of dead faints. See Pilgrimage.
The word is formed from the Flemilh pe/grim, or
Italian pelegrino, which fignifies ihe fame ; and thofe
originally from the Latin pcregrinus, a “ ftranger or
traveller.” 6
PILGRIMAGE, a kind of religious difcipline,
which confifts in taking a journey to fome holy place
in order to adore the relicks of fome deceafed faint. Pil¬
grimages began to be made about the middle ages of
the church •, but they w’ere moft in vogue after the
end of the nth century, when every one was for vifit-
ing places of devotion, not excepting kings and princes
themfelves; and even bilhops made no difficulty of be¬
ing abfent from their churches on the fame account.
The places moft vifited were Jerufalem, Rome, Com-
poftella (a), and Tours ; but the greateft numbers now
4 A refort
F 553 ]
(a) It deferves to be remarked here, that in the year 1428, under the reign of Henry VI. abundance of licences
W’ere granted from the crown of England to captains of Englilh (hips, for carrying numbers of devout perfcns to
the (brine of St James of CompofteUa in Spain j provided, however, that thofe pilgrims (hould firft take an oath
P I L [ 554 ] P I L
Pilgrinnage. refort to Loretto, in order to vifit the chamber of the
v “ ' bleffed virgin, in which the was born, and brought up
her fqn Jefus till he was 12 years of age. ' For the pil¬
grimage of the followers of Mahomet, fee Mahome¬
tanism.
In every country where popery was eftablifhed, pil¬
grimages were common •, and in thofe countries which
are ftill popifh, they continue. In England, the Ihrine
of §t Thomas a Becket was the chief refort of the
pious •, and in Scotland, St Andrews ; where, as tradi¬
tion informs us, was depolited a leg of the holy apoftle.
In Ireland they ftill continue ; for, from the beginning
of May till the middle of Auguft every year, crowds
of popifti pfenitents from all parts of that country re¬
fort to an iiland near the centre of Lough-Jin, or White
Lake, in the county of Donnegal, to the amount of
3000 or 4000. Thefe are moftly of the poorer fort,
and many of them are proxies for thofe who are richer ;
fome of which, however, together with fome of the
priefts and biftiops on occafion, make their appearance
there. When the pilgrim comes within fight of the
holy lake*, he muft uncover his hands and feet, and thus:
walk to the water-fide, and is taken to the ifland for
fixpence. Here there are two chapels and 15 other
houfes} to which are added confeflionals, fo contrived,
that the prieft cannot fee the perfon confefling. The
penance varies according to the circumftances of the
penitent; during the continuance of which (which is
fometimes three, fix, or nine days) he fubfifts on oat¬
meal, fometimes made into bread. He traverfes lharp
ftones on his bare knees or feet, and goes through a va¬
riety of other forms, paying fixpence at every different
confeflion. When all is over, the prieft bores a gimblet-
hole through the pilgrim’s ftaff near the top, in which
he faftens a crofs peg j gives him as many holy pebbles
out of the' lake as he cares to carry away, for amulets
to be prefented to his friends, and fo difmiffes him, an
objedl of veneration to all other papifts not thus initiated ,
who no fooner fee the pilgrim’s crofs in his hands, than
they kneel down to get his blefling.
There are, however, other parts of Ireland facred to
extraordinary worlhip and pilgrimage ; and the number
of holy wells, and miraculous cures, &c. produced by
them, is very great. That fuch things (hould exift in
this enlightened age, and in a Proteftant country, is in¬
deed ftrange ; but our wonder ceafes, wdien we reflefl
that it is among the loweft*, and perhaps the worft of the
people. They who carry external religion to an ex¬
treme, and place that confidence in ceremony which be¬
longs only to the fpirit of it, are feldom diftinguiftied ei¬
ther for their wifdom or their virtue. We do not deny,
however, that they who carry matters to the other ex¬
treme, may be equally deftitute of real knowledge and
genuine morality.
Dr Johnfon, in his Rajfelas, gives us fome obferva-
tions on pilgrimage, which are fo much to the purpofe,
that we think we cannot do better than lay them before
our readers. “Pilgrimage (faid Imlac, into whofe Pilgrimage
mouth the obfervations are put), like many other aits H.
of piety, may be reafonable or fuperftitious according to
the principles upon which it is performed. Long jour- v~'““
neys in fearch of truth are not commanded. Truth, fuch
as is neceffary to the regulation of life, is always found
where it is honeftly fought : change of place is no natu*
ral caufe of the increale of piety, tor it ipevitably pro¬
duces diflipation of mind. Yet fince men go every day
to view the fields where great aitions have been perfor¬
med, and return with ftronger impreflions of the event,
curiofity of the fame kind may naturally difpofe us to
view that country whence our religion had its begin¬
ning : and I believe no man furveys thofe awful fcenes
without fome confirmation of holy refolutions. That the
Supreme Being may be more eafily propitiated in one
place than in another, is the dream of idle fuperftition j
but that fome places may operate upon our own minds in
an uncommon manner, is an opinion which hourly ex¬
perience will juftify. He who fuppofes that his vices
may be more fuccefsfully combated in Paleftine, will,
perhaps, find hknfelf miftaken; yet he may go thither
without folly: he who thinks they will be more freely
pardoned, difhonours at once his reafon and religion.”
PILKINGTON, Ljetitia, a famous poetical ge¬
nius, the daughter of Dr Van Lewin, a phyfician of
Dublin, where (he wras born in 1712. She wras married
very young to the Rev. Matthew Pilkington, a poet al~
fo of no inconfiderable merit j and the two wits, as is
often the cafe, lived very unhappily together. They
were at length totally feparated, on the hulband acci¬
dentally difcovering a gentleman in her bedchamber at
two o’clock in the morning ; 3 circumftance w'hich (he
accounted for in a very unfatisfaftory manner. The
ftory is told at large in her Memoirs j where flie fays,,
“ Lovers of learning, I am fu-re, will pardon me, as I
folemnly declare it was the attractive charms of a new
book, wdiich the gentleman would not lend me, but
confented to ftay till I read it through, that was the foie,
motive of my detaining him.” As there are not want¬
ing fome who form objections to marrying learned
wives, the chance of fuch literary aflignations may per¬
haps be added to the lift of them. After this unlucky
adventure, Mrs Pilkington came to London j and ha¬
ving recourfe to her pen for fubfiftence, through the
means of Colley Cibber, {he lived for fome time on the
contributions of the great. She was however throw n into
the Marftialfea for debt j and being fet at liberty, opened
a pamphlet {hop. She raifed at length a handfome fub-
fcription for her Memoirs ; which are written with great
fprightlinefs and wit, 'containing feveral entertaining
anecdotes of Dean Swift, with whom (he was intimate,
as well as many pretty- little pieces of her owrn poetry.
This ingenious rvoman is faid at laft to have killed her-
felf with drinking. She died at Dublin, in 1750.
PILL, in pharmacy, a form of medicine refembling
a little ball, to be fwallowed whole j invented for fuch
as
not to take any thing prejudicial to England, not to reveal any of its fecrets, nor to carry out with them any more
gold or filver than what would be fufficient for their reafonable expences. In this year there went out thither from
England, on the faid pilgrimage, the following number of perfons. From London 280, Briftol 200, Wey¬
mouth 122, Dartmouth 90, Yarmouth 60, Jerfey 60, Plymouth 40, Exeter 30, Poole 24, Ipfwich 20, in all.
926 pejfons.
P I L [ 555 1 P I L
Pillar as cannot take bitter and ill-tafted medicinal draughts :
as alio to keep in readinebs for occadonal ufe without
decaying. See Materia Medic a Index.
PILLAR, in architeflure. See Architecture.
Pillar, in the manege, is the centre of the ring, or
manege-ground, round which a horfe turns, whether
there be a pillar in it or not. Befides this, there are
pillars on the circumference or {ides of the manege-
ground, placed at certain diftances, by two and two,
from whence they are called the two pillars, to diftin-
guilh them from that of the centre. The ufe of the pil¬
lar in the centre is for regulating the extent of ground,
that the manege upon the volts may be performed with
method and juftnefs, and that they may work in a
fquare, by rule and meafure, upon the four lines of the
volts; and alio to break unruly high-mettled horfes,
without endangering the rider. The two pillars are
placed at the diltance of two or three paces one from the
other ; and the horfe is put between thofe, to teach him
to rife before and yerk out behind, and put himfelf upon
raifed airs, &c. either by the aids or chaflifements.
Pompeifs Pillar. See Alexandria.
PILLARS, in antiquarian topography, are large
fingle Irenes let up perpendicularly. Thofe of them
which are found in this country have been the work of
the Druids ; but as they are the moll fimple of all mo¬
numents, they are unquellionably more ancient than
druidifm itfelf. They were placed as memorials record¬
ing different events j fuch as remarkable inftances of
•God’s mercies, contracts, fingular vidtories, boundaries,
and fometimes fepulchres. Various inftances of thefe
monuments eredled by the patriarchs occur in the Old
Teftament: fuch was that raifed by Jacob at Luz, af¬
terwards by him named Bethel; fuch alfo was the pillar
placed by him over the grave of Rachel. They were
likewife marks of execrations and magical talifmans.
Thefe ftones, from having long been confidered as
objects of veneration, at length were by the ignorant
and fuperftitious idolatroudy worftiipped ; wherefore, af¬
ter the introdudtion of Chriftianity, fome had croffes cut
on them, which was confidered as fnatching them from
the fervice of the devil. Vulgar fuperftition of a later
date has led the common people to confider them as per-
fons transformed into ftone for the puniihment of fome
crime, generally that of fabbath-breaking ; but this tale
is not confined to fingle ftones, but is told alfo of whole
circles: witnefs the monuments called the hurlers in
Cornwall, and Rollorick ftones in Warwicklhire. The
firft are by the vulgar fuppofed to have been once men,
and thus transformed as a punifhment for playing on the
Lord’s day at a game called hurling ; the latter, a pa¬
gan king and his army.
At Wilton, where the earl of Pembroke has a very
magnificent houfe, there is a pillar of one piece of white
Egyptian granite, which was brought from the temple
of Venus Genetrix at Rome, near 14 feet high and 22
inches diameter, with an infcrjption to Aftarte or Ve¬
nus.
PILLORY (colliflrigium, “ collum ftringens pil¬
lar m, from the French pillcur, i. e. depeculator ; or pr¬
iori, derived from the Greek ttvAo, janua, a “ door,”
becaufe one Handing on the pillory puts his head as it
v/ere through a door, and video), is an engine
made of wood to punilh offenders, by expofing them to
public view, and rendering them infamous. There is a Piliory,
Jlatute of the pillory, 51 Hen. III. And by ftatute it is piiot-
appointed for bakers, foreftallers, and thofe who ufe v
falfe weights, perjury, forgery, &c. 3 Inf. 219. Lords
of leets are to have a pillory and tumbrel, or it will be
the caufe of forfeiture of the leet j and, a village may be
bound by prefeription to provide a pillory, &c. 2 Hawk.
P. C. 73.
PILOT, the officer who fuperintends the navigation,
either upon the fea-coaft or on the main ocean. It is,
hov rever, more particularly applied by our mariners to
the perfon charged with the dire&ion of a Ihip’s courfe
on or near the fea-coaft, and into the roads, bays, rivers,
havens, &c. within his refpective diltridt.
Pilots of Ihips, taking upon them to conduft any ffiip
from Dover, &c. to any place up the river Thames, are
to be firft examined and approved by the matter and
wardens of the fociety of Trinity Houfe, &c. or fhall
forfeit 10I. for the firft offence, 20I. for the fecond, and
40I. for every other offence ; one moiety to the infor¬
mer, the other to the matter and wardens *, but any
mafter or mate of a {hip may pilot his own veffel up the
river: and if any {hip be loft through the negligence of
any pilot, he lhall be for ever after difabled to aft as a
pilot. 3 Geo. I. c. 13. Alfo the lord-warden of the
cinque ports may make rules for the government of pi¬
lots, and order a fufficient number to ply at fea to con-
duft {hips up to the Thames : 7 Geo. I. c. 21. No
perfon {hall aft as a pilot on the Thames, &c. (except
in collier fhips) without a licence from the mafter and
wardens of Trinity Houfe at Deptford, on pain of for¬
feiting 20I. And pilots are to be fubjeft to the go¬
vernment of that corporation j and pay ancient dues,
not exceeding is. in the pound, out of wages, for the
ufe of the poor thereof. Stat. 5 Geo. II. c. 20.
By the former laws of France, no perfon could be re¬
ceived as pilot till he had made feveral voyages and paf-
fed a ftrift examination; and after that, on his return
in long voyages, he was obliged to lodge a copy of his
journal in the admiralty ; and if a pilot occafioned the
lofs of a ffiip, he had to pay 100 livres fine, and to be
for ever deprived of the exercife of pilotage ; and if he
did it defignedly, be punifhed with death. Lex Mercat.
7°, 71*
The laws of Oleron ordain, That if any pilot defign¬
edly mifguide a {hip, that it may be call away, he {hall
be put to a rigorous death, and hung in chains : and if
the lord of a place, where a ffiip be thus loft, abet fuch
villains in order to have a ffiare of the wreck, he ffiall
be apprehended, and all his goods forfeited for the fa-
tisfaftion ox the perfons fuffering j and his perfon fhall
be faftened to a {lake in the midft of his own manfion,
which, being fired on the four corners, ffiall be burned
to the ground, and he with it. Leg. 01. c. 25. And
if the fault of a pilot be fo notorious, that the (hip’s crew
fee an apparent wreck, they may lead him to the hatches,
and ftrike off his head ; but the common law denies this
hafty execution: an ignorant pilot is fentenced to pafs
thrice under the (hip’s keel by the law's of Denmark.
Lex Mercat. 70.
The regulations with regard to pilots in the royal na¬
vy are as follow : “ The commanders of the king’s {hips,
in order to give all reafonable encouragement to fo ufe-
ful a body of men as pilots, and to remove ail their ob-
4 A 2 __ jeftiont
Pilot.
. . p 1 ,L r 556 i
/ jeflions to his majefty’s fervice, are ftriftly charged to place
~ treat them with good ufage, and an equal refpeft with
•warrant-officers.
“ The purfer of the ffiip is always to have a fet of
bedding provided on board for the pilots ; and the cap¬
tain is to order the boatfwain to fupply them with ham¬
mocks, and a convenient place to lie in, near their du¬
ty, and apart from the common men ; which bedding
and hammocks are to be returned when the pilots leave
the ffiip.
“ A pilot, when conducing one of his majefty’s
ffiips in pilot-water, (hall have the foie charge and com¬
mand of the ftiip, and may give orders for fleering, fet-
ting, trimming, or furling the fails j tacking the ffiip j
or whatever concerns the navigation : and the captain
is to take care that all the officers and crew obey his
orders. But the captain is diligently to obferve the con-
duft of the pilot j and if he judges him to behave fo ill
as to bring the ffiip into danger, he may remove him
from the command and charge of the fliip, and take fuch
methods for her prefervation as ftiall be judged necef-
fary; remarking upon the log book, the exaft hour and
time when the pilot-was removed from his office, and the
reafons affigned for it.
u Captains of the king’s ffiips, employing pilots in
foreign parts of his majefty’s dominions, fliall, after per¬
formance of the fervice, give a certificate thereof to the
pilot, which being produced to the proper naval officer,
he ffiall caufe the fame to be immediately paid 5 but if
there be no naval-officer there, the captain of his ma¬
jefty’s fhip fhall pay him, and fend the proper vouchers,
with his bill, to the navy-board, in order to be paid as
bills of exchange.
“ Captains of his majefty’s (hips, employing foreign
pilots to carry the ffiips they command into or out of
foreign ports, flrall pay them the rates due by the efta-
bhffiment or cuftom of the country, before they difcharge
them : whofe receipts being duly vouched, and fent,
with a certificate of the fervice performed, to the navy-
board, they ffiall caufe them to be paid with the fame
exa&nefs as they do bills of exchange.” Regulations and
InJlruBions of the Sea fervice, &c.
PiLOT-FiJh. See Gasterosteus, Ichthyology
Index.
Office tells us, that they are ffiaped like thofe mack¬
erels^ which have a tranfverfe line upon the body.
“ Sailors (continues he) give them the name of pilots, be-
caufe they clofely follow the dog-fiffi, fwimming in great
ffioals round it on all fides. It is thought that they
point out feme prey to the dog-fifh. They are not only
not touched, but alfo preferved by it againft all their
enemies.
It likewife follows the ffiark, apparently for the pur-
pofe of devouring the remains of its prey. It is pre¬
tended that it atfts as its pilot, d. he manner in which it
attends the ffiark, according to M. Daubenton, may
haye given rife to this name. It is faid to fwim at the
height of a foot and a half from the fnout of this vora¬
cious animal, to follow and imitate all its movements,
and to feize with addrefs every part of its prey which
the ftrark allows to efcape, and which is light enough to
buoy up towards the furface of the water. When the
ftiark, which has its mouth below, turns to feize any
fiffi, the pilot-fiffi ftarts away 5 but as foon as the ffiark
jrefumes his ordinary pofition, it returns to its former
P I M
It is laid, that in the gulf of Guinea thofe
fifties follow ffiips for the fake of the offals and human
excrements j and hence the Dutch give them the name
of dung fjh. It is remarkable, that though fo fmallthey
can keep pace with fliips in their fwifteft courfe.
PILTEN, a divifion of Courland, which lies in
Courland properly fo called, derives its name from the
ancient caftle or palace of Pilten, built by Valdemar II.
king of Denmark about the year 1220, when he found¬
ed a bifhop’s fee in this country for the more effectual
converfion of its Pagan inhabitants. This diftridt af¬
terwards fucceffively belonged to the Germans, then
again to the king of Denmark, the duke of Courland,
and to Poland ; and by virtue of the inftrument of re--
gency drawn up for this diftridt in the year 1717, the
government is lodged in feven Poliffi fenators or coun-
fellors, from whom an appeal lies to the king. The bi-
fliop of Samogitia alfo ftyles himfelf bifliop of Pilten.
The moft remarkable part of this diftridt is the pro¬
montory of Domefnefs, which projedts northward into
the gulf of Livonia. From this cape, a fand-bank runs
four German miles farther into the fea, half of which
lies under water, and cannot be difeerned. To the eafl:
of this promontory is an unfathomable abyfs, which is
never obferved to be agitated. For the fafety of veffels
bound to Livonia, two fquare beacons have been eredled
on the coaft, near Domefnefs church, oppofite to the
fand bank, and facing each other. One of thefe is twelve
fathoms high, and the other eight ; and a large fire is
kept burning on them from the firft of Auguft to the
firft of January. When the mariners fee thefe fires ap¬
pear as one in a diredt line, they may conclude that
they are clear of the extremity of the fand bank, and
ccnfequently out of danger ; but if they fee both bea¬
cons, they are in danger of running upon it. The dif-
tridf of Pilten contains leven panfhes, but no towns wor¬
thy of notice. The inhabitants are chiefly of the Lu¬
theran perfuafion.
PILUM, a miffive weapon ufed by the Roman fol-
diers, and in a charge darted upon the enemy. Its
point, we are told by Polybius, was fo long and fmall,
that after the firft difcharge it was generally fo bent as
to be rendered ufelefs. Ihe legionary foldiers made ufe
of the pilum, and each man carried two. The pilum
underwent many alterations and improvements, infomuch
that it is impcffible with any precifion to deferibe it.
Julius Scaliger laboured much to give an accurate ac¬
count of it, and would have efteemed fuccefs on this
head amongft the greateft bleffings of his life. This
weapon appears, however, to have been fometimes round,
hut moft commonly fquare, to have been two cubits long
in the ftaff, and to have had an iron point of the fame
length hooked and jagged at the end. Marius made a
material improvement in it; for during the Cimbrian
war, he fo contrived it, that when it ftuck in the ene¬
mies ftiield it thould bend down in an angle in the part
where the wood was connefled with the iron, and thus
become ufelefs to the perfon who received it.
PIMENTO, Piemento, Jamaica pepper, or A/l-
fpice, a fpecies of myrtus. See Myrtus, Botany ln±
dex.
“ The pimento trees grow fpontaneoufly, and in
great abundance, in many parts of Jamaica, but more
particularly on hilly fituations near the fea,- on tha
northern fide of that iiland 3 where they form the
moft
P I M [ 557 ] PIN
Fimento moft delicious groves that can pofiibly be imagined;
. II filling the air with fragrance, and giving reality, though
Pimple. jn a very. part Qf globe, to our great poet’s
defcription of thofe balmy gales which convey to the de-
lighted voyager
‘ Sabean odours from the fpicy fhore
* Of Araby the bleft.
‘ Cheat’d with the grateful fmell, old ocean fmiles.’
“ This tree is purely a child of nature, and feems to
mock all the labours of man in his endeavours to extend
or improve its growth: not one attempt in fifty to pro¬
pagate the young plants, or to raife them from the feeds,
in parts of the country where it is not found growing
fpontaneoully, having fucceeded. The ufual method of
forming a new pimento plantation (in Jamaica it is cal¬
led a walk) is nothing more than to appropriate a piece
of woodland, in the neighbourhood of a plantation al¬
ready exifting, or in a country where the fcattered trees
are found in a native date, the woods of which being
fallen, the trees are fuffered to remain on the ground till
they become rotten and perilh. In the courfe of twelve
months after the firll feafon, abundance of young pimen¬
to plants will be found growing vigoroully in all parts
of the land, being without doubt produced from ripe
berries fcattered there by the birds, while the fallen
trees, &c. afford them both Ihelter and ihade. At the
end of two years it will be proper to give the land a
thorough cleaniing, leaving luch only of the pimento
trees as have a good appearance, which will then foon
form fuch groves as thofe I have defcribed, and, except
perhaps for the firft four or five years, require very little
attention afterwards.
“ Soon after the trees are in bloffom, the berries become
fit for gathering •, the fruit not being fuffered to ripen
on the tree, as the pulp in that ftate, being moift and
glutinous, is difficult to cure, and when dry becomes
black and taftelefs. It is impoffible, however, to pre¬
vent fome-of the ripe berries from mixing with the reft •,
but if the proportion of them be great, the price of the
commodity is confiderably injured.
“ It is gathered by the hand •, one labourer on the tree,
employed in gathering the fmall branches, will give em¬
ployment to three below (who are generally women and
children) in picking the berries •, and an induftrious
picker will fill a bag of yolbs in the day.
“ The returns from a pimento walk in a favourable
feafon are prodigious. A fingle tree has been known
to yield 150 lbs. of the raw fruit, or one cwt. of the
dried fpice , there being commonly a lofs in weight of
one third in curing ; but this, like many other of the
minor produftions, is exceedingly uncertain, and per¬
haps a very plenteous crop occurs but once in five
years.”
PIMPINELLA, Burnet Saxifrage-, a genus of
plants belonging to the pentandria clafs. See Botany
Index.
PIMPLE, in Medicine, a fmall puftule arifing on
the face. By mixing equal quantities of the juice of
houfe-leek (fcdum minus), paffed through paper, and of
fpirit of wine reclified by itfelf, a white coagulum of a
very volatile nature is formed, which Dr Bughart com¬
mends for curing pimples of the face and fays, that
the thin liquor feparated' from it with fugarcandy is
an excellent remedy for thick vifcid phlegm in the Pin
breaft. ——y
PIN, in commerce, a little neceffary inftrument made
of brafs-wire, chiefly ufed by women in faftening and
adjufting their drefs.
In the year 1543, by ftatute 34 and 35 of Henry
VIII. cap. 6. it was enabled, “ That no perfon ffiall put
to fale any pinnes but only fuch as lhall be double-head¬
ed, and have the heads foldered fail to the fhank of the
pins, well fmootned, the ihank well-fliapen, the points
well and round filed, cauted, and ffiarpened.” Front
the above extradl it ihould appear that the art of pin-
making was but of late invention, probably introduced
from France ; and that our manufactories fince that pe¬
riod have wonderfully improved.
Though pins are apparently Ample, their manufac¬
ture is, however, not a little curious and complex. We
ihall therefore give our readers an account of it from
Ellis’s Campagna of London.
“ When the brafs-wire, of which the pins are form¬
ed, is firft received at the manufactory, it is generally
too thick for the purpofe of being cut into pins. The
firft operation therefore is that of winding it off from
one wheel to another with great velocity, and caufin'g
it to pafs between the two, through a circle in a piece
of iron of fmaller diameter : the wire being thus redu¬
ced to its proper dimenfions, is ftraitened by drawing
it between iron pins, fixed in a board in a zig-zag
manner, but fo as to leave a ftraight line between them :
afterwards it is cut into lengths of three or four yards,
and then into fmaller ones, every length being fufficient
to make fix pins ; each end of thefe is ground to a
point, which was performed when I viewed the manu¬
factory by boys who fat each with two fmall grinding
ftones before him, turned by a wheel. Taking up a
handful, he applies the ends to the coarfeft of the two
ftones, being careful at the fame time to keep each
piece moving round between his fingers, fo that the
points may not become flat: he then gives them a
fmoother and ffiarper point, by applying them to the
other ftone, and by that means a lad of 12 or 14 years
of age is enabled to point about 16,000 pins in an
hour. When the wire is thus pointed, a pin is taken
off from each end, and this is repeated till it is cut in¬
to fix pieces. The next operation is that of forming
the heads, or, as they term it, head-fpirming; which is
done by means of a fpinning-wheel, one piece of wire
being thus with aftonifhing rapidity wound round an¬
other, and the interior one being drawn out,-leaves a
hollow^ tube between the circumvolutions : it is then
cut with ffieers -, every two circumvolutions or tun s-
of the wire forming one head ; thefe are foftened by
throwing them into iron pans, and placing them in a
furnace till they are red hot. As foon as they are
cold, they are diftributed to children, who fit with
anvils and hammers before them, which they work
with their feet, by means of a lathe, and taking
up one of the lengths, they thruft, the blunt end
into a quantity of the heads which lie before them,
and catching one at the extremity, they apply them
immediately to the anvil and hammer, and by a
motion or two of the foot, the point and the head
are fixed together in much lefs time than it can b»
defcribed, and with a dexterity only to be acquired-
by pra6Ucej the fpedlator being in continual apprehen-
iloa.
Pin
II
Pindar.
P I N
fion for the fafety of their fingers ends.  
now finifhed as to its form, but itill it is merely brafs ;
it is therefore thrown into a copper, containing a folu-
tion of tin and the leys of wine. Here it remains for
fome time ; and when taken out affumes a white though
dull appearance : in older therefore to give it a polifli,
it is put into a tub containing a quantity of bran, which
is fet in motion by turning a ihaft that runs through its
centre, and thus by means of friftion it becomes per-
feffly bright. The pin being complete, nothing re¬
mains but to feparate it from the bran, which is perfor¬
med by a mode- exadlly fimilar to the winnowing of
the bran dying off and leaving the pin behind fit
corn
for immediate fale. I was the more pleafed with this
manufa&ory, as it appeared to afford employment to a
number of children of both fexes, who are thus not only
prevented from acquiring the habits of idlenefs and vice,
but are on the contrary initiated in their early years in
thofe of a beneficial and virtuous induftry.” See Nee¬
dles.
PINACIiV, among the Athenians, were tablets of
brafs infcribed with the names of all thofe citizens in
each tribe who were duly qualified and willing to be
judges of the court of Areopagus. Thefe tablets were
caft into a veffel provided for the purpofe, and the fame
number of beans, a hundred being white and all the reft
black, were thrown into another. Then the names of
the candidates and the beans wTere drawn out one by one,
and they whofe names were drawn out together with the
white beans were eledfed judges or fenators. In So¬
lon’s time there were only four tribes, each of which
choie 100 fenators; but the number of tribes afterwards
increaling, the number of fenators and judges increafed
to fo many hundreds more.
PINANG, the Chinefe name of the Areca Catechu
Lin. See Areca, Botany Index.
PINCHBECK, a factitious metallic fubftance, or an
alloy of zinc three parts, and of copper, four. See Che¬
mistry Index.
PINDAR, the prince of lyric poets, was born at
Thebes, about 520 years B. C. He received his firft
mufical inftrudtions from his father, who -was a flute-
player by profeflion j after which, according to. Sui-
das, he was placed under Myrtis, a lady of dittinguifti-
ed abilities in lyric poetry. It was during this period
that he became acquainted with the poetefs Corinna,
who was likewife a ftudent under Myrtis. Plutarch
tell us, that Pindar profited from the lefibns which
Corinna, more advanced in her ftudies, gave him at
this fchool. It is very natural to fuppofe, that the
firft poetical effufions of a genius fo full of fire and
imagination as that of Pindar would be wild and luxu¬
riant ; and Lucian has preferved fix verfes, faid to
have been the exordium of his firft effay ; in which he
crowded almoft all the fubjedls for fong which ancient
hiftory and mythology then furnifhed. Upon commu¬
nicating this attempt to Corinna, flie told him fmiling,
that he fliould fow with the hand, and not empty his
1 558 ] Pi N
dhe pin is whole fack at once. Pindar, howTever, loon quitted Pindar.
the leading firings of thefe ladies, his poetical nudes, ■v"—’
and became the difciple of Simonides, now arrived at
extreme old age : after which he foon furpafled all his 5
mafters, and acquired great reputation over all Greece :
but, like a true prophet, he was lefs honoured in his
own country than elfewhere ; for at Thebes he was fre¬
quently pronounced to be vanquifhed, in the mufical and
poetical contefts, by candidates of inferior merit.
The cuftom of having thefe public trials of ikill in
all the great cities of Greece was now fo prevalent,
that but little fame was to be acquired by a muftcian
or poet any other way than by entering the litis •,
and we find, that both Myrtis and Corinna publicly
dilputed the prize with him at Thebes. Pie obtained
a vidlory over Myrtis, but was vanquilhed five dif¬
ferent times by Corinna. P he judges, upon occafions
like thefe, have been frequently accufed of partiality or
ignorance, not only by the vanquilhed, but by pofte-
rily } and if the merit of Pindar was pronounced in¬
ferior to that of Corinna five feveral times, it was,
Pays Paufanias, becaufe the judges were more fenfible
to the charms of beauty than to thofe of mufic and poe¬
try (a).. Was is not ftrange, faid the Scythian Ana-
charfis, that the Grecian artills wTere never judged by
artifts, their peers ?
Pindar, before h»cquitted Thebes, had the vexa¬
tion to. lee his Dithyrambics traduced, abufed, and
turned into ridicule, by the comic poets of his time j
and Athenseus tells us, that he was leverely cenlured
by his brother lyrics, for being a lipogrammatift, and
compofing an ode from which he had excommunicated
the letter S. Whether thefe cenfures proceeded from
envy or contempt cannot now be determined; but
they wrere certainly ufeful to Pindar, and it was necefi
fiiry that he Ihould be lalhed for fuch puerilities.
Thebes feems to have been the purgatory of our
young bard : when he quitted that city, as his judge¬
ment was matured, he avoided moft of the errors for
which he had been chaftifed, and fuddenly became the
wonder and delight of all Greece. Every hero, prince,
and potentate, defirous of lafting fame, courted the mufe
of Pindar.
He feems frequently to have been prefent at the
four great.feftivals, of the Olympian, Pythian, Nemean,
and Ifthmian games, as may be inferred from feveral cir-
dumftances and expreflions in the odes which he com-
pqfed for the vi&ors in them all. Thofe at Olympia,
who were ambitious of having their atchievements cele¬
brated by Pindar, applied to him for an ode, which was
firft fung in the Pry taneum or town-hall of Olympia, where
there was a banqueting room, fet apart for the enter¬
tainment of the conquerors. Here the ode was rehear-
fed by a chorus, accompanied by inftruments. It was
afterwards performed in the fame manner at the trium¬
phal entry of the viftor into his own country, in prs-
ceflions, Or at the facrifices that were made with great
pomp and folemnity on the occafion.
Pindar,
(a) Paufanias fays, that Corinna was one of the moft beautiful wromen of her time, as he judged by a pic¬
ture of her which he law at Lanagris at the place where the public exercifes were performed. She ? as re-
prefented with her head ornamented by a riband, as a memorial of the victories die had obtained over Pindar at
Thebes.
2
P I N
Pindar, in Ms fecond Ifthmian ode, has apologized for
the mercenary cuftom among poets, of receiving money
for their eompofitions. “ The world (fays he) is grown
interfered, and thinks in general with the Spartan
philofopher Ariilodemus, that money only makes the
■man : a truth which this fage himlelf experienced, ha¬
ving with his riches loft all his friends.” It is fuppofed
that Pindar here alludes to the avarice of Simonides,
who firft allowed his mufe to fell her favours to the
higheft bidder.
There is no great poet in antiquity whofe moral
character has been lefs cenfured than that of Pindar.
Plutarch has preferved a fingle verfe of his Epicedium
or Dirge that was fung at his funeral; which, fhort
and ftmple as it is, implies great praife : This man was
plea fing to Jlrangers, and dear to his fellow-citizens. His
works abound with precepts of the pureft morality:
and it does not appear that he ever traduced even his
enemies ^ comforting himfelf, for their malignity, by a
maxim which he inferted in his firft Pythic, and which
afterwards became proverbial, That it is better to be en¬
vied than pitied.
Paufanias fays, that the character of poet was truly
confecrated, in the perfon of Pindar, by the god of
verfe himfelf; who was pleafed, by an exprefs oracle,
to order the inhabitants of Delphos to fet apart for
Pindar one half of the firft-fruit offerings brought by
the religioUs to his fhrine, and to allow him a confpi-
cuous place in his temple, where, in an iron chair, he
ufed to fit and ling his hymns in honour of that god.
This chair tvas remaining in the time of Paufanias,
feveral centuries after, and ftiown to him as a relick
not unworthy of the faneftity and magnificence of that
place.
But though Pindar’s mufe was penuoned at Delphos,
and well paid by princes and potentates elfewhere, fhe
feems, however, fometimes to have fung the fponta-
neous ftrains of pure frxendfhip. Of this kind were,
probably, the verfes befkwed upon the mufician Mi¬
das, of Agrigentum in Sicily, who had twice obtain¬
ed the palm of viftory by his performance on the flute
at the Pythic games (b). It is in his 12th Pythic
ode that Pindar celebrates the vidtory of Midas over all
Greece, upon that injlrument which Minerva herfelf had
invented (c)
Fabricius tells us, that Pindar lived to the age of
90; and, according to the chronology of Dr Blair, he
died 435 years B. C. aged 86. His fellow citizens
eredted a monument to him in the Hippodrome at
Thebes, which was ftill fubfifting in the time of Pau¬
fanias ; and his renowm was fo great after his death,
that his pofterity derived very confiderable honours and
privileges from it. When Alexander the Great at-
P I N
tacked the city of Thebes, he gave exprefs orders to
his foldievs to fipare the houfe and family of Pindar.
The Lacedemonians had done the fame before this pe¬
riod ; for when they ravaged Boeotia and burned the
capital, the following words were written upon the
door of the poet: Forbear to burn this houfe, it was
the dwelling of Pindar. Refpedt for the memory of
this great poet continued fo long, that, even in Plu¬
tarch’s time, the heft part of the facred vidtim at the
Theoxentan feftival was appropriated to his defeend-
ants.
PINDARIC ode, in Poetry, an ode formed in
imitation of the manner of Pindar. See Poetry, n°
136, &.C.
PINDUS, in Ancient Geography, not a fingle moun¬
tain, but a chain of mountains, inhabited by different
people of Epirus and Theffaly j feparating Macedonia,
Theffaly, and Epirus : An extenfive chain, having Ma¬
cedonia to the north, the Perrhoebi to the weft, the Do-
lopes to the fouth, and the mountain itfelf of Theffaly
(Strabo).
Pindus, a Doric city of ALtolia, fituated on the
cognominal river, which falls into the Cephiffus (Stra¬
bo.) ,
PINE, in Botany. See Pinus, Botany Index.
PlNE-Apple. See Bromelia, Botany Index; and
for an account of the mode of cultivating the pine-apple,
fee Gardening.
PINE A, or pigne, in commerce, is a term ufed in
Peru and Chili, for a kind of light, porous maffes, or
lumps, formed of a mixture of mercury and filver-duft
from the mines. The ore, or mineral, of filver, when
dug out of the veins of the mine, is firft broken and then
ground in mills for the purpofe, driven by water with
iron peitles, each of 200 pounds weight. The mineral,
when thus pulverized, is next lifted, and then worked
up with'water into a pafte ; which, when half dry, is cut
into pieces, called cuerpos, a foot long, weighing each
about two thoufand five hundred pounds.
Each piece or cuerpo is again kneaded up with fea-
falt, which, diffolving, incorporates with it. They
then add mercury, from 10 to 20 pounds for each
cuerpo, kneading the pafte afrefh until the mercury
be incorporated therewith. This office, which is ex¬
ceedingly dangerous on account of the noxious quali¬
ties of the mercury, is always made the lot of the poor
Indians. This amalgamation is continued for eight or
nine days 5 and fome add lime, lead, or tin ore, &c. to
forward it; and, in fome mines, they are obliged to
ufe fire. To try whether or no the mixture and a-
malgamation be fufficient, they waffi a piece in water •,
and if the mercury be white, it is a proof that it has
had its effefl j if black, it muft be ftill farther work¬
ed.
r 559 1
(B) This Midas is a very different perfonage from his long-eared majefty of Phrygia, whofe decifion in fa¬
vour of Pan had given fuch offence to Apollo ; as is manifeft, indeed, from his having been cotemporary with
Pindar. <
(c) The moft extraordinary part ©f this mufician’s performance that can be gathered from the fcholiaft
upon Pindar, was his finiihing the folo, without a reed or mouth-piece, which broke accidentally while he was
playing. The legendary account given by the poet in this ode, of the occafion upon which the flute was in¬
vented by Minen-a, is diverting : “It was (fays he) to imitate the howling of the Gorgons, and the biffing
of their Makes, which the goddefs had heard when the head of Medufa (one of thefe three anti-graces) was cut oft
by Per feus.”
PIN [ 560 ] PIN
Pinea
. II
Pineau.
ed. Wlien finlflied, it is fent to the lavatories, which
are large bafcms that empty fucceflively into one ano¬
ther. The paile, &c. being laid in the uppermoft of
thefe, the earth is then wafhed from it into the reft by
a rivulet turned upon it} an Indian, all the while, ftir-
ring it with his feet, and two other Indians doing the
like in the other bafons. When the water runs quite
clear out of the bafons, the mercury and filver are found
at bottom incorporated. This matter they call pel/a,
and of this they forfn the pineas, by expreffing as much
of the mercury as they can; firft, by putting it in
woollen bags, and prefling and beating it ftrongly;
then, by ftamping it in a kind of wooden mould, of
an oflagonal form, at bottom whereof is a brafs plate
pierced full of little holes. The matter, when taken out
of the mould, is laid on a trivet, under which is a large
veflel full of water ; and the wdiole being covered with
an earthen head, a fire is made round it.
The mercury Hill remains in the mafs, and is thus
reduced into fumes, and, at length condenfing, it is
precipitated into the water, leaving behind it a mafs
of filver grains of different figures, which, only joining
or touching at the extremes, render the matter very
porous and light. This, therefore, is the pinea, or
pigne, which the workmen endeavour to fell fecretly
to veffels trading to the South fea 5 and from which
thofe, who have ventured to engage in fo dangerous a
commerce, have made fuch vaft gains. Indeed the
traders herein muft be very careful •, for the Spanifti
miners are arrant knaves, and to make the pignes
weigh the more, they often fill the middle with fand
or iron. -
PINEAL gland. See Brain, Anatomy Index.
PINEAU, Gabriel du, a diftinguifhed lawyer, was
born at Angers in 1573. He wrent afterwards to
Paris, and pled wdth eclat before the parliament and
great council. Upon his return to Angers, he became
a counfellor in the prefidial court. He was confulted
by all the neighbouring provinces, and had an aftive
hand in all the great affairs of his time. Mary de Me-
dicis conferred upon him the office of matter of re-
quefts, and in her difgrace wdffied to fupport herfelf
by his credit and counfels ; but Du Pineau, ahvays at¬
tentive to wffiat he owed on the one hand to the mo¬
ther of his king, and on the other to the king himfelf,
never ceafed to infpire that princefs with fentiments of
peace.
In 1632 Louis XIII. by way of reward, appointed
him mayor and captain-general of the city of Angers;
a fituation in which he merited the flattering title of
Father of the People. He had no refpecl of perfons j
for he was equally acceffible to the poor and the great.
This wmrthy citizen died the 15th of October 1644,
at the age of 71. His houfe was a kind of academy,
where regular conferences wTere held, and attended by
young officers, advocates, and other literary characters.
In thofe conferences every one freely ftated the diffi¬
culties v'hich occurred to him upon fubjeCls either of
law or hiftory ; and when Pineau fpoke, all w'as made
clear; but he was always the laft in delivering his fenti¬
ments, becaufe he perceived that too much deference
was paid to his opinion. His writings are, 1. Latin
notes, in addition to thofe of Du Moulin, upon the ca¬
non law, and prinied along with the works of that
eminent lawyer by ihe care of Francis Pinfon. 2. Com¬
4
mentaries, obfervations, and confultations, upon fevcral
important queftions reipecling the laws both of Anjou
and of France, with lome differtations upon different
fubjefts, &c. reprinted in 1725, in 2 vol. folio, by the
care of Livoniere, who has enriched them with very
ufeful remarks. The editor fays, that “ Du Pineau
is a little inferior to the celebrated Du Moulin on the
civil law, but that he is more accurate than the other
upon the canon law.”-—Menage made thefe two verfes
upon his death :
Plflcaw
. it .
I'inelii.
Pine/lus periit, Themidis plus ille facerdos.
In proprio judex limine perpetuus.
PINEDA, John, a writer of hiftory, was born at Se¬
ville of a noble family, and entered into the iociety of
Jefuits in 1572. He taught philofophy and divinity in
feveral colleges; and devoted his time to the ftudy of
the Holy Scriptures. That he might render that itudy
the eafierj he made himfelf mafter of the oriental lan¬
guages. We have of his writings, 1. Two volumes of
Commentaries upon the book of J ob, in folio. 2. Two
upon Ecclefiaftes. 3. A General Hiftory of the Church,
in Spanifti, 4 vol. in folio. 4. A Hiftory of Ferdi¬
nand III. in the fame language, in folio. He died in
1637, much regretted by the members of his lociety,
and by the public in general.
PINELLI, John Vincent, a diftinguiflied literary
char after, was born at Naples, and was fon of Count
Pinelli, a noble Genoefe, who had fettled in that city,
and had acquired a handfome fortune in the way of
trade. After receiving a liberal education, he quitted
the place of his nativity, and repaired to Padua, where
he took up his refidence at the age of 24. Being a
great lover of fcience, he gave a preference to that city
on account of its famous univerfity, which brought to it
a number of learned men. He had an excellent library,
which confifted of a choice colleftion of books and ma-
nufcripts, and which he continued to enrich till the
hour of his death. His literary correfpondence, not on¬
ly in Italy, but through the moft of Europe, procured
him all the new w orks which w'ere worthy of a place in
his colleftion. The authors themfelves were often for¬
ward to pay their refpefts to him. In many cities of
Italy he had perfons employed to fearch, at leaft once a
month, the flails of thofe artificers w ho make ufe of old
parchments, fuch as lute-makers, fievewrights, and
others ; and by this means he had the good fortune of¬
ten to fave from deftruftion fome valuable fragments.
His paffion for knowledge embraced all the fciences 'r
but hiftory, medals, antiquities, natural hiftory, and par¬
ticularly botany, wrere his favourite ftudies. He was
confulted from all quarters, and the extent of his ac¬
quaintance with the learned wTorld was very great. He
correfponded with Juftus Lipfius, Jofeph Scaliger, Si-
gonius, Poffevin, Peter Pithou, and a great many
others, who have all paid the higheft compliments ts
his erudition. Infenfible to all the pleafures of life, and
acquainted only wfith thofe of the mind, he had a great
diflike to plays, entertainments, fhows, and every thing
which moft excites the curiofity of other men. During
the fpace of 43 years that he lived at Padua, he was
never known to he out of the city but twice ; once on
occafion of a plague which mfefted it; and afterwards
on a voyage to Naples, wrhich he made at the earneft
folicitation of his friends. In ffiort, Pinelli was gener¬
ous1,
PIN [ 561 1 PIN
Pine
Ping-leang
fou.
ous, fympathizlng, and compaflionale, particularly to
men of letters, whofe rvants he often anticipated. His
zeal for the progrefs and advancement of fcience render-
J ed him very communicative of his knowledge and of his
books} but this was always done with judgement and
difcre ticn. He died in 1601, aged 68, without having
publifhed any work. Paul Gualdo, who has written
Pinelli’s lite, does not fpecify the number of volumes
of which his rich library confifted •: he only infornts us,
that when it was tranfported by fea to Naples, it was
packed up in 130 cheits, of which 14 contained manu-
fcripts; but it did not go wholly to his heirs. The
fenate of Venice caufed their feal to be fet upon the
manuicripts, and took away whatever concerned the
affairs of the republic, to the number of 200 pieces.—
“ I compare (fays Prendent de Thou) Pinelli to Titus
Pomponius; for, as that illuftrious Roman was called
Ajtwk, Pinelli alio bore the title of Venetian, on account
of the great affection which the republic of Venice had
for him.
PINET, Antony du, lord of Noroy, an ecclefiafli-
cal writer, lived in the 16th century, and was a native
of Befan^on. He was ftrongly attached to the Pro-
teftant religion, and a bitter enemy to the church of
Rome. His book, entitled La Cortformite des Eglifes
Reformes de France, and de AFg/ife primitive, printed
at Lyons, 1564, in 8vo ; and the notes which he added
to the French tranflation of the Fees of the Pope’s Chan¬
cery, which was printed at Lyons, in 8vo, 1564, and
reprinted at Amflerdam in 1700, in 1 2mo, plainly dif-
cover his fentiments. He publifhed the laft-mentioned
performance under this title : Taxe dcs parties cafuelles
de la boutique du Rape, in Latin and French, with fome
notes taken from decrees, councils, and canons, in order
to aicertain the difcipline anciently obferved in the
church. In the epiftle dedicatory, he affumes the tone
of a declared enemy to the court of Rome. He apolo¬
gizes for having prefented this book “ to a fociety fo holy
as yours (the Proteftants), in which are heard only
hymns, pfalms, and praifes, to the Lord our God:
but it is proper to fliow to the villain his villany, and
the fool his folly, left one fhould be thought to re-
femble them.” We fee by this fpecimen, that Pinet
had no more politenefs in his ftyle than in his manners.
His tranflation of Pliny’s Natural Hiftory, printed at
Lyons in -2 vol. folio, 1566, and at Paris, 1608, was
formerly much read. Though there are a good many
errors in it, it is yet very ufeful at prefent, efpecially for
thofe who underftand Pliny’s Latin, on account of the
tranflator’s refearches, and a great number of marginal
notes. Pinet alfo publifhed Plans of the principal for-
treffes in the world at Lyons, 1564, in folio.
PING leang fou, a city of China in the pro¬
vince of Chen-fi. It is one of the moft confiderable
fifriptio/i cities of the weftern part of the province, and is fi-
voH * luat£d oo the river Kin-ho. The air here is mild ;
i3‘ '' and the agreeable views which the furrounding moun¬
tains prefent, added to the ftreams which water the
country, render it a very delightful refidence. It has
under its jurifdiflion three cities of the fecond clafs
and (even of the third. In this diftridt is a valley fo
deep and narrow, that it is almoft impervious to thg
light : a large highway, paved with fquare fiones, runs
through it.
VOL. XVI. Part II.
Grofier's
General
PINGUICULA, Butter wort ; a genus of plants PbguWa
belonging to the diandria clafs. See Botany Index. II
_ PENGUIN, or Penguin, in Ornithology, a genus 0f,p,pr,(*enis-.
birds of the order anferes. See Aptenodytes, Orni¬
thology Index, or page 507.
PINION, in Mechanics, an arbor, or fpindle, in the
body whereof are feveral notches, which catch the teeth
of a wheel that ferves to turn it round *, or it is a leffer
wheel that plays in the teeth of a larger.
PINK, a name given to a fhip with a very narrow
ftern •, whence all veffels, however fmall, whofe Herns
are fafhioned in this manner, are called pink-Jlerned.
Pink. See Dianthus, Botany Index.
PINNA, in Zoo/q§y, a genus of fhel’-fifh belonging
to the order of vermes teftacea. See CoNCHOLOGY In¬
dex.— Pliny, who gives fome account, perhaps not very
correft, of the hiftory of fome of the fpecies of this ge¬
nus, (lib. ix. 51.) fays, the fmalleft of all the kinds is
called the pinnoteres, and therefore liable to injury j
this has the prudence to hide itfelf in the thells of oy-
flers. Again, lib. ix. 66. he fays, the pinna is of the
genus of fhell-filh 5 it is produced in muddy waters, al¬
ways ereft, nor ever without a companion, which feme
call the pinnoteres, others the pinnophylax. This fome-
times is a fmall fquill, fometimes a crab, that follows
the pinna for the fake of food. The pinna, upon open¬
ing its fhell, expofes itfelf as a prey to the fmalleft
kind of fillies ; for they immediately affault her, and,
growing bolder upon finding no refiftance, venture in.
I he guard, watching its time, gives notice by a bite ;
upon which the pinna, clofing its Ihell, fliuts in, kills,
and gives part of whatever happens to be there to its
companion.
The pinna and the crab together dwell,
For mutual fuccour, in one common Ihell.
1 hey both to gain a livelihood combine ;
That takes the prey, when this has given the fign.
From hence this crab, above his fellows fam’d,
By ancient Greeks wraspinnoteres nam’d.—Oppian.
PINNACE, a fmall veflel navigated with oars and
fails, and having generally two marts, which are rigged
like thofe of a fchooner.
PINNACE is alfo a boat ufually rowed with eight oars.
See, the article Boat.
PINNACLE, in Archite&ure, the top or roof of
a houfe, terminating in a point. This kind of roof
among the ancients was appropriated to temples 5 their
ordinary roofs were all flat, or made in the platform
way.
PINNATED leaves. See Botany Index.
PINNATIFID leaves. See Botany Index.
PINNOTERUS, or Pinnophylax, is a kind of
crab-filh, furniflied with very good eyes. It is faid to
be the companion of the pinna marina. They live and
and lodge together in the fame fliell, wdiich belongs to
the latter. When it has occafion to eat, it opens its
valves, and fends out its faithful purveyor to procure
food. If during their labour the pinnoterus perceives
the polypus, it immediately returns to wam its blind
friend of the danger, wdien, by fhutting its valves, it
efcapes the rage of its enemy j but when the pinnoterus
loads itfelf with booty without moleftation, it makes a
gentle noife at the opening of the fliell, and when ad-
4 B mitted
P I N
mitted tlie two friends feafl on the fruits of its induftry.
See Pinna, &c.
j PINT (pinta), a veflel, or meafure, ufed in eftima-
ting the quantity of liquids, and even fometimes of dry
things.—Budteus derives the word from the Greek
others from the German, pint, a little meafure of wine;
Nicod from the Greek tumiv, “ to drink.”
The Eng/ijh pint is twofold; the one for wine mea¬
fure, the other for beer and ale meafure. See Mea¬
sure.
PINTADiV, a fpecies of Procellaria.
PINTLES, certain pints or hooks faflened upon
the back part of the rudder, with their points down¬
wards, in qrder to enter into, and reft upon, the goo-
gtngs, fixed in the flern-poft, to hang the rudder. See
Hel^.
PI NT OR, Peter, ,phyfician, was born at Valentia
in Spain, in the year 1420, and was phyfician to Alex¬
ander VI. whom he follotved to Rome, where he prac-
tifed with great fuccefs. He has left behind him two
performances of cohfiderable merit, 1. Aggregator Sen-
tentiarum DoElorum de Curatione in Pe/lilentia, printed
at Rome 1499, in folio. 2. De Morbo Dado et Occu/to ‘
his Tanporibus Affiigenti, Nc. printed at Rome, 1500,
in 410, black letter : a book extremely fcarce, unknown
to Luifini and Altruc, and which traces the venereal
difeafe to the year 1496. Pintor died at Rdme in 1503,
aged 83 years.
PINPURICCIO, Bernardino, a celebrated Italian
painter, rvas born at Perufia in 1454. Pie ivas the
difciple of Peter Perugiuo, under whom he became fo
good an artiil, that he employed him on many occa-
lions as his affiilant. He principally painted hiftory
and grotefque ; but he alfo excelled in portraits, among
which thofe of Pope Pius II. and Innocent VII1. of
Giulia Farnefe, Cmfar Borgia, and Oueen Ifabella of
Spain, are particularly diftinguiflied. The moll me¬
morable performance of Piuturiccio is the hillory of
Pius II. painted in ten compartments in the monaftery of
Siena ; in which undertaking, Raphael, then a young
man, and bred under the fame mailer,'afiilted him fo
far as to Iketch out cartoons of many parts of the com-
pofition. The llory vf his death is worth relating,
elpecially as it illullrates Lis character. The lall work
he was engaged in was a Nativiti/ for the monallery
of St brands at Siena : the monks accommodated him
with a chamber to work in, which they cleared of all
the furniture, except one old trunk or chelt that ap¬
peared too rotten to move; but Pinturiccio, naturally
politive and peevgh, infilled on its being taken away, and
the monks, willing to gratify him, complied. It wTas
no fooner llirred than one of the planks burfling, out
tumbled 500 pieces of gold, which had been fecreted
there for many years. The monks were overjoyed at
Ending this treafure, and the painter proportionably
mortified at lofing his chance of the difcovery by his
indifcreet obllinacy : it afiedded his fpirits fo much that
he furvived but a few months, and it was generally con-
fidered as the caufe of his death.
PINUS, the Pine-tree; a genus of plants belong¬
ing to the monoecia clafs. See Botany Index. The
pine-tree was well known to the ancients, and has been
defcribed and celebrated both by their philofophers and
poets. Pliny enumerates no lefs than fix fpecies of trees
of this genus ; and it is mentioned by Virgil both in his
P I N
Eclogues, his Georgies, and his Alneid ; by Horace Piuus.
in his Odes; by Ovid in his Metamorphofes ; by Sta- v—-
tins; and by Catullus, &.c. Macrobius relates an anec¬
dote concerning the cones of pine-trees, which in com¬
mon language were called poma pine a ^ “ pine-apples.”
There lived in the Auguftan age one Valinius, who by
fome means had irritated the Roman people fo much
that they pelted him with Hones. When he entertain¬
ed them with gladiators, to fave himfelf from fuch
treatment for the future, he procured an edift from the
ediles, that no perfon fhould throw any thing but apples
in the amphitheatre. It accidentally happened that at
this time Cafcellius, eminent for his wit as well as know¬
ledge of the law, was confulted on the queflion, whether
a pine-apple (the cone of the pine) was legally included
in the term potnum, “ an apple ?” It is an apple (faid
he) if you intend to fling it at Vatinius *. A deci- * Saturn.
fion by which the edicl in his favour did not much^'1^
mend his fituation: for Martial reprefents it dangerous^’
to come under this tree, becaufe the cones in his time
were of fo great a fize and weight, probably enlarged
by cultivation for ages.
Nuces Pinea>.
Poma fumur Cyheles : procul hinc difeede% viator,
Ne cadat in miferum n 'dira ruina caputj xiiL
There are generally reckoned 14 fpecies of this genus ; ^ 25*
of which the moil remarkable are thefe following :
1. The pinea, pineajier, or wild pine, grows naturally
on the mountains in Italy and the fouth of France. It
grows to the flze of a large tree ; the branches extend
to a confiderable diftance; and while the trees are young,
they are fully gavniihed with leaves, efpecially where
they are not fo clofe as to exclude the air from thofe
within ; but as they advance in age, the branches ap¬
pear naked, and all thofe which are fituated below be¬
come unlightly in a few7 years ; for which reafon they
are now much lefs in elleem than formerly.
2. The pinus pine a, or Hone pine, is a tall evergreen
tree, native of Italy and Spain. It delights in a faridy
loam, though like moll others it will grow well in al-
moll any land. Refpefting the ufes of this fpecies,
Hanbury tells us that “ the kernels are eatable, and by
many preferred to almonds. In Italy they are ferved
up at table in their defferts.—They are exceeding whole-
fome, being good for coughs, colds, ccnfumptions, &c.
on which account only this tree defetves to be propa¬
gated.” Hanbury continues : “ It may be very proper
here to take notice of a very great and dangerous mif-
take Mr Miller has committed, by faying, under this
article of Hone-pine, that feeds kept in the cones will be
good, and grow if they are fown ten or twelve years
after the cones have been gathered from the trees ;
whereas the feeds of this fort, whether kept in the cones
or taken out, are never good after the firH year ; and
though fometimes a few7 plants will come up from the
feeds that are kept in the cones for two years before, yet
this is but feldom ; neither muH a tenth part of a crop
be expefled. This caution is the more neceflary, as
feveral gentlemen who had cones, upon reading Mr
Miller’s book, and finding the feeds would take no
damage when kept there, deferred the work for a fea-
fon or two, when they thought they fhould have more
conveniency either of men or ground for their purpofe ;
and were afterwvds wholly difappointed, no plants ap-
, , pearing,
[ 562 1
Treatife on
Planting
and Orna¬
mental
? I N [56
Pinti?. pearing, the feeds being by that time fpoiled and worth
—V nothing.”
3. The rubra, commonly called the Seats yfr or fnnc.
It is common throughout Scotland, whence its name 5
though it is alfo found in moft of the other countries
of Europe. M. du Hamel, of the Royal Academy of
Sciences, mentions his having received feme feeds of it
from St Domingo in the Weft Indies 5 and thence con¬
cludes, that it grows indifferently in the temperate,
frigid, and torrid zones. The wood of this tree is
the red or yellow deal, which is the moft durable of
any of the kinds yet known. The leaves of this tree
are much ftrorter and broader than thofe of the former
fort, of a grayifh colour, growing two out of one
ftieath ; the cones are fmall, pyramidal, and end in r.ar-
ro-^points } th,ey are of a light colour, and the feeds are
fmall.
4. The pitius picca, or yew-leaved fir, is a tall ever¬
green, and a native of Scotland, Sweden, and Germany.
This fpecies includes the filver fir and the balm of Gi¬
lead fir. The firft of thefe is a noble upright tree.
Mr Marfham fays, “ The talleft trees I have feen vTere
fpruce and filver firs in the valleys in Switzerland. I
faw feveral firs in the dockyards in Venice 40 yards
long; and one of 39 yards w7as 18 inches diameter at
the fmall end, I was told they came from Switzer¬
land.”
The branches are not very numerous, and the bark
is fmooth and delicate. The leaves grow fingly on the
branches, and their ends are (lightly indented. Their
Gardening, upper furface is of a fine ftrong green colour, and. their
under has an ornament of twro white lines running
lengthwife on each fide the midrib; on account of
winch filvery look this fort is called xht jilver fir. The
cones are large, and grow7' ereft ; and, wrhen the warm
weather comes on, they foon' (lied their feeds; which
Ihould be a caution to all who ui(h to raife this plant,
to gather the cones before that happens.
The balm of Gilead fir has of all the forts been moft
coveted, on account of the great fragrance of its leaves ;
though this is not its only gooff property : for it is a
very beautiful tree, naturally of an upright growth,
and the branches are fo*ornamented with their balmy
leaves, as to exceed any of the other forts in beauty.
The leaves, which are very clofely fet on the branches,
are broad ; and their ends are indented. Their upper
furface, wThen healthy, is of a fine dark-green colour,
and their under has white lines on each fide the mid¬
rib lengthwife, nearly like thofe of the filver fir. Thefe
leaves when bruifed are Very finely feented ; and the
buds, wftiich fwell in the autumn for the next year’s
(hoot, are very ornamental all winter, being turgid,
and of a fine browm colour : and from thefe alfo exudes
a kind of fine turpentine,, of the fame kind of (though
heightened) fragrancy. The tree being wmunded in
any part, emits plenty of this turpentine ; and Hanbury
fays, “ it is fuppofed by many to be the fort from whence
the balm of Gilead is taken, which occafions this tree
being fo called. But this is a miftake ; for the true
balm of Gilead is taken from a kind of terebinthus :
though I am informed, that w’hat has been coiled!ed
from this tree has been fent over to England from A-
merica (where it grows naturally), and often fold in the
(hops for the true fort.”
The fxlver fir is very hardy, and will grow in any
, 1 PIN
foil or fituation, but always makes the greateft pregrefs
in rich loamy earth. The balm of Gilead fir muft be
planted in deep, rich, good earth ; nor wall it live long
in any other. The foil may be a black mould, or of a
fandy nature, if it be deep enough, and if the roots have
room enough to ftrike freely.
9. The pin us abies, or European fpruce fir, a native
of the northern parts of Europe and of Afia, includes.
the Norway fpruce and long-coned Cornifh fir. The
former of thefe is a tree of as much beauty while grow¬
ing as its timber is valuable when propagated on that
account. Its growffh is naturally like the filver, up¬
right : and the height it will afpire to may be eafily
conceived, when wTe fay that the white deal, fo much
coveted by the joiners, &c. is the wcod of this tree ;
and it may perhaps fatisfy the curious reader to know7,
that from this fir pitch is drawn. The leaves are of a
dark-green colour; they (land fingly on the. branches,
but the younger (hoots are very clofely garnilhed with
them. They are very narrow ; their ends are pointed ;
and they are pcffeffed of fuch beauties as to excite admi¬
ration. The cones are eight or ten inches long, and
hang downwards.
The better the foil is, the fafter will the fpruce fir
grow, though it will thrive very well in moft of our
Englfth lands. In ftrong loamy earth it makes a fur-
prifing progreCs; and it delights in frelh land of all forts,
which never has been worn out by ploughing, &c.
though it be ever fo poor. I he long-coned Corniftr fir
differs fcarcely in any relpect from the Norway fpruce,
except that the leaves and the cones are larger.
6. The pinas Canadenfis, American or Newfoundland
fpruce fir, a native of Canada, Bennfylvania, and other
parts of North Amrerica, includes three varieties. The
white Newfoundland fpruce, the red Newfoundland
fpruce, and the black Newfoundland fpruce. Thefe,
however, differ fo little, that one deferiptien is common
to them all. They are of a genteel upright growth,
though they do not (hoot fo freely or grow fo faft with
us as the Norway fpruce. The •javes are of the fame
green, and garnilh the branches in the fame beautiful
manner as thofe of that fpecies ; only they are narrower,
fhorter, and (land clofer. The greateft difference is ob-
fervable in the cones; for thefe are no more than about
an inch in length, and the feales are cloudy placed. In
the cones, indeed, confifts the difference of thefe three
forts : thofe of the white fpecies are of a very light brown
colour ; thofe of the red fpecies more of a nut-brown or
reddifh colour ; and thofe of the black fpecies of a dark
or blackifti colour. Befides this, there is fcarcely any
material difference ; though it is obfervable, that this
trifling variation feems to be pretty conftant in the plants
raifed from the like feeds. Thefe forts will often flower,
and produce cones when only about five or fix feet high ;
and indeed look then very beautiful : but this is a fign
of weaknefs in the plant, which it does not often fairly
get over. *
7. The pin us balfamea, or hemlock fir, a cative of
Virginia and Canada, poffeffes as little beauty as any of
the fir tribe ; though, being rather fcarce in proportion,
it is deemed valuable. It is called by feme the yew¬
leaved fir, from the refemblance of the leaves to thofe
of the yew-tree. It is a tree of low growth, with but
few branches; and thefe are long and (lender, and (pread
abroad without order. The leaves do not garnifh the
4 B 3 branches
Plnus.
Ibid.
Finns.
, , r P 1 N f 564 ]
^ branches fo plentifuily as thofe of any olher fort of fir. among
-The cones are very fmall and rounded" ; they are about
half an inch long; and the fcales are loofely arranged.
VVe receive thefe cones from America, by which we
raife the plants; though this caution fhould be given to
tne planter, that this tree is fond of moifi rich ground,
and in fuch a kind of foil will make the greatelf pro-
gref*
8. The pinus orientalis, or oriental fir, a native of the
Eaif, is a low but elegant tree. The leaves are very
fhort, and nearly fquare. 1 he fruit is exceeding fmall,
and hangs downward ; and the whole tree makes an
agreeable variety with the other kinds.
9. Ihe Jirobus, Lord Weymouth’s pine, or North
American white pine. This grows fometimes to the
height of 100 feet and upwards, and is highly valued
on account of its beauty. The bark of the tree is very
fmooth and delicate, efpecially when young; the leaves
are long and flender, five growing out of one {heath ;
the branches are pretty clofely garnilhed with them,
and ^ thus make a fine appearance. The cones are long,
flenaer, and very loofe, opening with the fir if warmth
ot the fpring; fo that if they are not gathered in win¬
ter, the fcales open and let out the feeds. The wood
of this fort is eifeemed for making mails for fliips. In
£)ueen Anne s time there was a law made for the pre-
feivatiou ot the!e trees, and for the encouragement of
their growth in America. Within thefe lail ijo years
tney have been propagated in Ifritain in confiderable
plenty.
With refpedl to the culture of this fpecies, Mr Han-
bury, after fome more general directions, continues thus,
I have known gentlemen, who, in attempting to raife
thefe trees, have feen tne young plants go off without
perceiving the caufe ; and the more watering and pains
they have taken, have found the plants periilt in this
way more and more, to their great mortification and
aifonifhment. In the fpring following thefe plants ihould
be pricked cut in beds half a foot afunder each way; and
here they may Hand two years, when they may be either
finally planted out, or removed into the nurfery, at the
didance of one foot afunder, and two feet in the rows,
if caie has Deen taken of them in the nuviery, they may
be removed at a confiderable height with great affurance
of fuccefs : for it is much eafier to make this pine grow
than any of the other forts: fo that where they are want¬
ed for ornament in parks, open places, &c. a fhow of them
may be made in a little time.
“ Ihe foil the Weymouth pine delights in moft is a
fandy loam ; but it lilies other foils of an inferior nature :
and although it is not generally to be planted on all lands
like the Scotch fir, yet I have feen it luxuriant and
healthy, making ftrong flioots, on blue and red clays,
and other forts of ftrong ground. On ftony and flaty
ground, hkewife, I have feen fome very fine trees; fo
that I believe whoever is defirous of having plantations
of this pine, need not be curious in the choice of his
ground.”
10. The pini/s tee cl a, or fwamp-pine, is a tall evergreen
tree, a native of the fwamps of Virginia and Canada.
There are feveral varieties of this genus which Han-
bury enumerates and deferibes : fuch as, iff, The three¬
leaved American fwamp-pine. 2d, The two-leaved
American pine. 3d, The yellow American pine, the
yellow tough pine, and 'the tough pine of the plains;
P I N
„ which there is but little variety,
b a third pine.. 3th, 1 he frankiheenfe pine.
The dwarf pine.
J-litre ai.e (continues our author) many other
forts of American pines, which we receive frqm thence
with the hke cant names of thofe of the above,
which 1 have chofen to retain, as they will probably be
continued to be fcnt over ; and that the gardener re¬
ceiving them as Inch may belt know what to do with
lueoi. In many ot thofe forts I lee at prefent no ma-
lenal dideience ; 10 .am induced to think they are ihe
lame, lent over with different names. Some of the
forts above-mentioned differ in very few reipe&s p but
I have chofen to mention them, as a perfon may be
lupplied with .the feeds from Pennfyl vania, Jerfey, Vir¬
ginia, Carolina, occ. wnere they all grow naturally :
and having once obtained the leeds, and from them
plants, they will become pleafmg objefts of his niceit
oblervalions.”
Ihe pmus cedrus, ranked by Tournefort alid
Pimis.
others under larix, famous for its duration, is that po¬
pularly called by us the cedar of Lebanon, by the an¬
cients cedrus tnagna or the great cedar ; alio cede elate,
y-dpi>MTA; and iometimes the Phoenician or Syrian ce-
oar, Irom the country where it grows in its greateif per-
feciion. It is a coniferous evergreen, of the bigger fort,
bearing large roundilh cones of fmooth fcales, Handing
ered, the leaves being fmall, narrow, and thick fet.—
They fometimes counterfeit cedar, by dyeing wood of a
reddilh hue : but the Imell difeovers the cheat, that of
true cedar being very aromatic. In fome places, the
wood of the cajou-tree paffes under the name of cedar,
on Account of its reddilh colour and its aromatic fmeil
which lomewhat referable that of fantal. Cedar-wood
is reputed, almoft immortal and incorruptible ; a prero¬
gative v.hich it owes chiefly to its bitter talk, which the-
worms cannot endure. For this reafon it was that the
ancients tiled cedar tablets to write upon, efpecially for
things of importance, as appears from that expreffion of
j er^us’ C£dra digit a locutus. A juice was alfo drawn,
from cedar, with which they fmeared their books and
writings, .or other matters, to preferve them from rot-
? which is alluded to by Horace : by means of which
it was, that Numa’s books, written on papyrus, were
preferved entire to the year 535, as we are.informed by
Pliny. J
^ kjolomon s temple, as well as his palace, were both of
this wood. That prince gave King Hiram feveral cities
iOr the cedars he had furnilhed him on thefe occafions,
Cortes is faid to have ereeled a palace at Mexico, in
which were 7000 beams- of cedar, molt of them 120
feet long, and 12 in circumference, as we are informed
by Herrera. Some tell us of a cedar felled in Cyprus
130 feet long, and 18 in diameter. It was ufed fur the,
mam-mall in the galley of King Demetrius. Le Bruyn
affures us, that the two biggeft he law on Mount Leba¬
non,, meafured, one of them 57 palms, and the other-
47, m circumference. In the temple of Apollo at Uti¬
ca, there were cedar trees near 2000 years old ; which
yet were nothing to that beam in an oratory of Diana at
Seguntum in Spain, faid to have been brought thither
200 years before the deftrudlion of Troy. Cedar is of
fo. dry a nature, that it will not endure to be faftened
with iron nails, from which it ufually fhrinks ; fo that
they commonly fallen it with pins of the fame wood.
“ The
p 1 N [ 565 1 PI N
i: The ftatue (fays Hanbury) of the great goddefs
at Ephefus was made of this material ; and, if' this tree
abounded with us in great plenty, it might have a
principal ihare in our mod fuperb edifices. The eillu-
V'.a conftantly emitted from its wood are faid to purify
tne air, and make rooms wholefome. Chapels and
places let apart for religious duties, being wainfcolted
with this wood, i dpire the worlhippers with a more
fjlema awe. It is not obnoxious to worms ; and emits
an oil which will preferve cloth or books from worms
or corruption. The law-dull will preferve human bo¬
dies fi-ora putrefaflion ; and is therefore faid to be
plentifully tiled in the rites ol embalming, where prac-
tifed.”
It is remarkable that this tree is not to be found as
a native in any other part of the world than Mount Li-
banus, as far as hath yet been difcovered. What we find
mentioned in Scripture of the lofty cedars can be nowife
applicable to the common growth of this tree ; fince,
from the experience we have of thofe now growing in
England, as alfo from the teilimony of feveral travellers
wno have via ted thofe few remaining trees on Mount
Libanus, they are not inclined to grow very lofty, but
on' the contrary extend their branches very far 5 to
winch the allulion made by the Pfalmifi: agrees very
well, when he is deferibing the flourilhing Hate of a
people, and fays, “They lhall Tpread their branches
like the cedar-tree.”
Rauwolf, in his Travels, fays, there were not at that
time (L e. anno 1574) upon Mount Libanus more than
26 trees remaining, 24 of which Hood in a circle ; and
tire other two, which Hood at a fmall dillance, had their
branches almoll confumed with age ; nor could he find
any younger tree coming up to fucceed them, though he
looked about diligently for fome. Thefe trees (he fays)
were growing at the foot of a fmall hill, on the top of
tire mountains, and amongil the fnow. Thefe having
very large branches, commonly bend the tree to one fide,
but are extended to a great length, and in fo delicate and
pleafaat order, as if they were trimmed and made even
with great diligence, by which they are eafiiy diliin-
guithed, at a great difiance, from fir-trees. The leaves
(continues he) are very like to thofe of the larch- tree,
growing clofe together in little branches upon fmall
brown fhoots.
Maundrel, in his Travels, fays, there were but 16
large trees remaining when he vifited the mountain,
fome of which were of a prodigious bulk, but that there
were many more young ones of a fmaller fize : he mea-
fured one of the largeft, and found it to be 1 2 yards fix
inches in_ girth, and yet found, and 37 yards in the
fnread of its boughs. At about five or fix yards from
the ground it was divided into five limbs, each of which
was equal to a great tree. What Maundrel hath related
was confirmed by a gentleman who was there in the year
1720, with this difterence only, viz. in the dimeniions'
of the branches of the largeft tree, which he meafured,
and found to he 22 yards diameter. Now, whether Mr
Maundrel meant 37 yards in circumference of tliefpread-
ing branches, or the diameter of them, cannot be deter¬
mined oy his words; yet either of them well agrees with
this laft account.
12. There is another fpecies, viz. the larch-tree, which
the old botanifts ranked under larix, with deciduous
leaves, and oVal ootufe cones. It grows naturally upon
the Alps and Apennines, and of late has been very much
propagated in Britain. It is of quick growth, and the
trunk riles to 50 leet or more ; the branches are fiender,
tneir ends generally hanging downward, and are garnifh-
ed wall long narrow leaves which arife in clutters from
one point, fpreading open above like the hairs of a pain¬
ter’s bruih : they are of a light green, and fall away in
autumn. In the month of April the male llowers ap¬
pear, which are difpofed in-form of fmall cones 5 the fe¬
male dowers are collected into oval obtufe cones, which
m fome fpecies have bright purple tops, and in others
they are white: thefe differences are accidental; the
cones are about an inch long, obtufe at their points \ the
feales are fmooth, and lie over each other; under each
fcaie there are generally lodged two feeds, which have
wings, d here are other two varieties of this tree, one
of which is a native of America, and the other of Sibe¬
ria. Ibe cones of the American kind which have been
brought to Britain feem in general to be larger than
thofe of the common fort.
- “ .Many encomiums (fays Hanbury when fpeaking
of tnis ipecies) have been beftowed on the timber of the
larch : and we find fuch a favourable account of it in
ancient authors, as dhould induce us to think it would
be proper for almoft any ufe. Evelyn recites a ftory of
Witfen, a Dutch writer, that a ftiip built of this timber
and. cyprefs had been found in the Numidian fea, twelve
fathoms under water, found and entire, and reduced to
fuch a hardnefs as to refift the fharpeft tool, after it had
lain fubmerged above 1400 years. Certain it is this is
an excellent wood for Chip and houfe-building. At Ve¬
nice this wood is frequently ufed in building their houfes,
as well as in Switzerland, where thefe trees abound : fo
that, without all doubt, the larch excels for mafts for
flnps, or beams for houfes, doors, windows, &c. parti¬
cularly as it is faid to refift the worm.
“ In Switzerland (a) their houfes are covered with
boards of this wood cut out a foot fquare ; and, as it
emits a refinous fubftance, it fo diffufes itfelf into every
joint and crevice, and becomes fo compact and clofe, as
well as fo hardened by the air, as to render the covering
proof againft all weather. But as fuch covering for
houfes would caufe great devaftation in cafe of fire, the
buildings
(a) “ Between Bex and Bevieux (fays Coxe in his Trave/s in Switzerland), I obferved the larch in meat
plenty. Painters, from the time of Pliny to that of Raphael, trufted their works to this wood, which the
Roman naturahlt fines immortate lignum. The wood is- reckoned excellent for all works which are to lie un¬
der water : and the borderers on the lake of Geneva prefer it for building their veffels. In thefe parts I faw
molt beautiful woods of chefnut. Haller fays_that they extend fome leagues: he alfo informs us, that they are
found in other parts of Switzerland, and even in defert places in fome of the tranfalpine parts. Accident muft
iiavebrought them thither, as, it appears from Pliny that thefe trees were firft introduced into Europe from .
Plfcus.
•buildings ar
P I M [
onFmed to a limited diftance by an order
of police from the magiftrates. I he wood when firlh
laid op the houfes, is faid to be v:ry white ; but tnis co¬
lour, in two or three years is changed, by means of the
fun and refin, to a black, which appears like a ImoOih
fhinirig varnilh.”
Of the common larch there are feveral varieties. The
flowers which-the commonefl fort exhibits early in the
fpring are of a delicate red colour j another lort produ¬
ces white flowers at the fame feafon, and thefe have a
delightful effeft among thole of the red fort ; whillt ano¬
ther, called the Black Newfoundland larix, increafes the
variety, though by an afpeft little differing from the
others. There are alfo larches with greenilh flowers,
pale red, &c. all of which are accidental varieties from
feeds. Thele varieties are eafily diftinguilhed, even when
out of blow : the young (hoots of the white-flowering
larch are of the lighteft green, and the cones when ripe
are nearly white. The red flowering larch has its fhoots
of a rcddirii caft, and the cones are of a brown colour 5
whilft the cones and fhoots of the black Newfoundland
larch are in the fame manner proportionally tinged.
The cones, which are a very great ornament to feveral
forts of the pines, are very little to thefe. Iheir chief
beauty confifts in the manner of their growth, the na¬
ture and beauty of their pencilled leaves and lair
566 ] . PIN
Siberia ufe the tender tops, and even the bark rubbed off
in' the fpring, as an antifcorbutic. The kernels of the
nuts of the amygdalus nana give a very pleafing flavour
to brandy ; and, when preifed, afford a bitter oil in large
quantities. The way of deftroying the bitter is by di-
gefting it in the fun with fpirit of wine, and it then be¬
comes fweet and extremely agreeable.
From the larch-tree is extra&ed what is erroneoufly
called Venice turpentine. This fubftance, or natural bal-
fam, flows at firit without incifion } when it has done
dropping, the poor people rvho wait in the fir woods
make incifions at about two or three feet from the
ground into the trunks of the trees, into which they fix
narrow troughs about 20 inches long. The end of thefe
troughs is hollowed like a ladle ; and in the middle is a
fmall hole bored for the turpentine to run into the re¬
ceiver which is placed below it. As the gummy fub-
flance runs from the trees, it paffes along the doping
gutter or trough to the ladle, and from thence runs
through the holes into the receiver. The people who
gather it vifit the trees morning and evening from the
end of May to September, to colled! the turpentine out
of the receivers. When it flows out of the tree, Venice
turpentine is clear like water, and of a yellowfifti white j
but, as it grows older, it thickens and becomes of a ci¬
tron colour. It is procured in the greatefl: abundance in
Pinus.
flowers j for the cones that fucceed them are fmall, of the neighbourhood of Lyons, and in the valley of St
a whitifli, a reddilh, or a blackifh-brown colour, and
make no figure.
The pinus cedrus and pinus larix are propagated by
fowing in March on a bed of light earth expofed to the
morning fun. The leed muff bfe covered half an inen
thick with fine light earth, and the beds watered, at
times when the weather is dry. In about fix weeks the
plants will appear j they muft at this time be carefully
guarded from the birds, fliaded from the fun and winds,
and kept very clear of weeds. In the latter end of
April the following year, they may be removed into
beds of frefh earth, placing them at ten inches diftance
everyway. They are to be kept here twro years, and
fuch of them as feem to bend mult be tied up to a flake
to keep them upright. They may afterwards be plant¬
ed in the places where they are to remain. They thrive
Martin near St Lucern in Switzerland.
Though we have already noticed the manner of cul¬
tivating fome of the particular fpecies of this genus, and
have alfo remarked the ufes of fome of them, we ffiall
finifh the article with a few general obfervations on the
culture and dies of the whole..
Culture. All the forts of pines are propagated by
feeds produced in hard woody cones. The wray to get
the feeds out of thefe cones is to lay them before a gentle
fire, wLich will caufe the cells to open, and then the
feeds may be eafily taken out. If the cones are kept en¬
tire, the feeds will remain good for fome years ; fo that
the fureft rvay of preferving them is to let them remain
in the cones till the time for fowing the feeds. If the
cones are kept in a warm place in fummer, they will
open and emit the feeds ; but if they are not expofed to
well on the fides of barren hills, and make a very pretty - the heat, they will remain clofe for a long time. The
beft feafon for fowincr the pines is about the end of
figure there.
Refpe&ing the ufes of this tree, Dr Pallas, in his
Flora RoJJica, informs us, that if it is burnt, and _ the
wood confumed, the internal part of the wood diftils
copioufly a drying reddilh gum, a little lefs -glutinous
than gum arabic, fomewhat of a refinous tafte, but wrhol-
ly foluble in water. At the inftigation of M. Kinder,
this gum has lately been fold in the Ruffian (hops under
the name of gumvu 0renburgerfs, but which our author
thinks fhould be called gummi Urahenfe or laricis. It is
eaten by the Woguli as a dainty, and is faid to be nutri¬
tious and antifcorbutic. Some manna was gathered from
the green leaves, but -it could never be condenfed. The
Ruffians ufe the boletus laricinus a? an emetic in inter-
mittents, and to check the leucorrhcea. At Bafchir and
Siberia the inhabitants fprinkle the diy powder on the’
woun ds of oxen and horfes, as a detergent and anthel¬
mintic. The nuts of the pinus cembra, the fame author
afferts, are eaten as luxuries in Ruflia, and are even ex¬
ported with the fame view. The unripe cones give a
very fragrant oil, termed balfamic. Fne inhabitants of
March. When the feeds are fown, the place fhould be
covered with nets to keep off the birds ; otherwife, when
the plants begin to appear with the hulk of the feed on
the top of them, the- birds will peck off the tops, and
thus deftroy them.
Ufes. From the firft fpecies is extradled the com¬
mon turpentine, much ufed by farriers, and from which
is drawn the oil of that name. The procefs of making
pitch, tar, refin, and turpentine, from thefe trees, is very
familiar. In the fpring time, when the fap is moft free
in running, they pare off the bark of the pine tree, to
make the fap run dowm into a hole which tney cut at
the bottom to receive it. In the way, as it runs down,
it leaves a white matter like cream, but a little thicker.
This is very different from all the kinds of refin and tur¬
pentine in ufe, and it is generally fold to be ufed in the
making of flambeaux inftead of white bees wax. 1 he
matter that is received in the hole at the bottom is taken
up with ladles, and put in a large balket. A great part
of this immediately runs through, and this is the com¬
mon
PIN C 567 ] PIP
‘inus. mon turpentine. This is received into flone or earthen
pots, and is ready for fale. The thicker matter, which
remains in the bafket, they put into a common alembic,
adding a large quantity of water. They diftil this as
long as any oil is feen fwimming upon the water. This
oil they feparate from the furface in large quantities, and
this is the common oil or Ipirit of turpentine. The re¬
maining matter at the bottom of the Hill is common yel¬
low refin. When they(have thus obtained all that they
can from the fap of the tree, they cut it down, and hew¬
ing the wood into billets, they fill a pit dug in the earth
with thefe billets, and, fetting them on fire, there runs
from them, while they are burning, a black thick mat¬
ter. This naturally fells to the bottom of the pit, and
this is the tar. The top of the pit is covered with tiles,
to keep in,the heat-, and there is at the bottom a little
hole, out at which the tar runs like oil. If this hole be
made too large, it fets the whole quantity of the tar on
fire ; but, if fmall enough, it runs quietly out.
The tar, being thus made, is put up in barrels; and
if it be to be made into pitch, they put it into large boil¬
ing vefiels, without adding.anything to it. It is then
luffered to boil a while, and being then let out, is found
■when cold to be what we call pitch.
A decofKon of the nuts or feeds of the firft fpecies in
milk, or of the extremities of the branches pulled in
fpring, is faid, with a proper regimen, to cure the moft
inveterate fcurvy. The wrood of this fpecies is not va¬
lued ) but that of the Scots pine is fuperior. to any of
the reft. It is obfervable of the Scots pine, that when
planted in bogs, or in a moift foil, though the plants
make great progrefs, yet the wmod is white, foft, and
little efteemed but when planted in a dry foil, though
the growth of the trees is there very flow, yet the wmod
is proportionably better. Few trees have been applied
to more ufes than this. The tailed: and ftraigheft are
formed by nature for mafts to our navy. The timber is
refinous, durable, and applicable to numberlefs domeftic
purpofes, fuch as flooring and wainfccftting of rooms,
making of beds, chefts, tables, boxes, &c. From the
trunk and oranches of this, as well as moft others of the
pine tribe, tar and pitch is obtained. By incifion, bar-
ras, Burgundy pitch, and turpentine, are acquired and
prepared. The refinous roots are dug out of the ground
in many parts of the Highlands, and, being divided into
fmall fplinters, are ufed by the inhabitants to burn,
inftead of candies. At Loch-Broom, in Rofs-fhire
the fithermen make ropes of the inner bark • but hard
neceflity has taught the inhabitants of Sweden, Lapland,
and Kamtfchatka, to convert the fame into bread. To
cffefl this, they, in the fpring feafon, make choice of
the talleft and feireft trees ; then flopping off carefully
the outer bark, they colleft the foft, white, fucculent
interior bark, and dry it in the (hade. When they have
occafion to ufe it, they firft toaft it at the fire, then
grind, and after fteeping the flour in warm water to take
off the refinous tafte, they make it into thin cakes, -which
are baked for ufe. On this ftrange food the poor inha¬
bitants are fometirqes con {trained to live for a whole
year ; and, we are told, through cuftem, become at laft
even fond of it. Linnaeus remarks, that this fame bark-
bread wdll fatten fwine 5 and humanity obliges us to wifh,
that men might never be reduced to the neceflity of rob¬
bing them of fuch a food. The interior bark, of which
the above-mentioned bread is made, the Swedifti boys
frequently peel off the trees in the fpring, and eat raw
with greedy appetite. From the cones of this tree is
prepared a diuretic oil, like the oil of turpentine, and a
refinous extrafl, which has fimilar virtues with the bal-
fam of Peru. An infufion or tea of the buds is highly
commended as an antifcorbutic. The farina^ or yellow
powder, of the male-flowers, is foaaetimes in the fpring
carried away by the winds, in fuch quantities, where
the trees abound, as to alarm the ignorant with the no¬
tion of its raining brimftone. The tree lives to a great
age 5 Linnaeus affirms to 400 years.
PIONEERS, in the art of war, are fuch as are com¬
manded in from the country, to march with an army
for mending the ways, for working on intrenchments
and fortifications, and for making mines and approach¬
es. The foldiers are likewife employed for all thefe pur¬
pofes. Moft of the foreign regiments of artiltery have
half a company of pioneers, well inftrufled in that im¬
portant branch of duty. Our regiments of infantry and
cavalry have three or four pioneers each, provided with
aprons, hatchets, faws, fpades, and pick-axes. Each
pioneer muft have an axe, a few, and an apron ; a cap
with a leather crown, and a black bears-lkin front, on
which is to be the king’s creft in white, on a red ground ;
and the number of the regiment is to be on the back
part of it.
PIP, or Pep, a difeafe among poultry, confifting of
a white thin {kin, or film, that grows under the tip of
the tongue, and hinders their feeding. It ufually arifes
from want of water, or from the drinking puddle-water,
or eating filthy meat. It is cured by pulling oft' the film
with the fingers, and rubbing the tongue with felt.
Hawks are particularly liable to this difeafe, efpecially
from feeding on {linking flelh.
PIPE, in building, &c. a canal, or conduit, for the
conveyance of water and other liquids. Pipes for water,
water-engines, &c. are ufually of lead, iron, earth, or
wood : the latter are ufually made of oak or elder.
Thefe of iron are caft in forgestheir ufual length is a-
bout two feet and a half: feveral of thefe are commonly
feftened together by means of four ferews at each end,
with leather or old hat between them, to flop the wa¬
ter. Thofe of earth are made by tfie potters 5 thefe are
fitted into one another, one end being always made
wider than the other. To join them the clofer, and pre¬
vent their breaking, they are covered with tow and
pitch : their length is ufually about that of the iron pipes.
The wooden pipes are trees bored with large iron au-
gres, of different fizes, beginning with a left, and then
proceeding with a larger fuccemvely j the firft being
pointed, the reft being formed like fpoons, incrcafing
in diameter, from one to fix inches or more : they are
fitted into the extremities of each other (as reprefeuted
fig. 2.), and are fold by the foot.
Wooden pipes are bored as follows. The machine
reprefented fig. 1. is put in motion by the wheel A,
which is moved by a current of water ; upon the axle
of this wheel is a cog-wheel B, which caufes the lan¬
terns C, D, to turn horizontally, whofe common axis
is confequently in a perpendicular direction. The lan¬
tern I) turns at the fame time two cog-wheels, E and
F : the firft, E, which is vertical, turns the augre winch
bores the wood; and the fecond, F, which is horizon¬
tal, caufes the carriage bearing the piece to advance by
means of the arms H, I, which take hold of ihe not-.
che§. •
PIP [ 568 ] PIP
p'Pp, ches in the wheel K. The firft, H, by means of the
^P1^* , notches, draws the wheel towards F j and the other, I,
puihes the under-poft of the wheel in an oppofite direc¬
tion 5 both which motions tend to draw the carriage to¬
wards F, and confequently caufe the augre to pierce the
wood. The augre being from 9 to 12 feet in length,
and of a proportionable bignefs, it itill be neceffary to
have two pieces, as L, L, to fupport its weight, and
caufe it to enter the piece to be bored with the fame
uniformity.
For the conftruftion of leaden pipes, fee the article
Plumbery.
Air-PlPES. See AlR-Pipes.
Pipes of an Organ. See Organ.
Bag-PlPE. See BAG-Pipe.
Horn-PiPE. See Hornpipe.
Tobacco-PlPE, a machine ufed in the fmoking of to¬
bacco, confiding of a long tube, made of earth or clay,
having at one end a little cafe, or furnace, called* the
bowl, for the reception of the tobacco, the fumes where¬
of are drawn by the mouth through the other end.
Tobacco pipes are made of various fafhions ; long, fhort,
plain, worked, white, varnifhed, unvarnilhed, and of
various colours, &c. The Turks ufe pipes three or
four feet long, made of rufhes, or of wood bored, at the
end whereof they fix a kind of a pot of baked earth,
which ferves as a bowl, and which they take off after
fmoking.
Pipe, alfo denotes a veffel or meafure for wine, and
things meafured by wine-meafure. See Barrel and
Measure.
Pipe, in Mining, is where the ore runs forwards end-
wfife in a hole, and doth not fink downwards or in a vein.
Pipe ,Pipa, in Law, is a roll in the exchequer, call¬
ed alfo the great roll. See the next article.
PlPF.-OJfice, is an office wherein a perfon called the
clerh of the pipe, makes out leafes of crown-lands, by
warrant from the lord-treafurer, or commiffioners of the
treafury, or chancellor of the exchequer. The clerk of
the pipe makes out alfo all accounts of flieriffs, See.
and gives the accountants their quietus ef. To this of¬
fice are brought all accounts which pafs the remembran¬
cer’s office, and reitiain there, that if any ftated debt be
due from any p&rfon, the fame may be drawn down in¬
to the great roll of the pipe : upon which the comptrol-
4 ler iflues out a writ, called fummons of the pipe, for
recovery thereof; and if there be no goods or chattels,
the clerk then draws down the debts to the lord treafur-
er’s remembrancer, to wTrite eflreats againft their lands.
All tallies which vouch the payment'of any fum contain¬
ed in fuch accounts are examined, and allowed by the
chief fecohdary of the pipe. Befides the chief clerk in
this office, there are eight attorneys or fworn clerks,
and a comptroller.
PiPE-Fifh. See Syngnathus, Ichthyology Index.
Sea PIPES, the trivial name of univalve ffiells belong¬
ing to the genus dentalis. See Concholotsy Index.
PIPER, a fpecies of fiffi. See Trigla, Ichthyolo¬
gy Index.
Piper, Pepper; a genus of plants belonging to the P
diandria clafs. See Botany Index. There are 20
fpecies,' of wdiich the molt. remarkable is the firiboa,
with oval, heart-fhaped, nerved leaves, and reflexed
fpikes, This is the plant which produces the pepper fo
much ufed in food. It, is a flirub whofe root is frnall,
fibrous, and flexible; it rifes into a ftem, which re¬
quires a tree or prop to fupport it. Its wTood has the
fame fort of knots as. the vine 5 and when it is dry, it
exadlly refembles the vine-branch. The leaves, which
have a flrong fmell and a.pungent tafte, are of an oval
fhape j but they diminilh towards the extremity, and
terminate in a point. From the flower-buds, which
are white, and are fometimes placed in the middle and
fometimes at the extremity of the branches, are produ¬
ced fmall berries refembling thofe of the ,currant tree.
Each of thefe contains between 20 and 30 corns of pep¬
per they are commonly gathered in Oftober, and ex-
pofed to the fun feven 01; eight days. The fruit which
was green at firft, and afterwards red, when ftripped
of its covering affumes the appearance it has when we
fee it. The largeft, heavieft, and lead fhrivelled, is
the beft.
The pepper plants flourifhes in the ifland of Java, Su¬
matra (a), and Ceylon, and more particularly on the
Malabar coaft. It is not fown, but planted 5 and great
nicety is required' in the choice of the fhoots. It pro¬
duces no fruit till the end of three years; but bears fo
plentifully the three fucceeding years, that fome plants
yield between fix and feven pounds of pepper. The bark
then begins to fhrink ; and the fhrub declines fo faft,
that in 1 2 years time it ceafes bearing.
The culture of pepper is not difficult: it is fufficient
to plant it in a rich foil, and carefully to pull up the
wTeeds that grow in great abundance round its roots,
efpecially the three firll years. As the fun is highly ne¬
ceffary to the growth of the pepper plant, when it is ready
to bear, the trees that fupport it. muff be lopped to pre¬
vent their fhade from injuring the fruit. When the fea-
fon is over, it is proper to crop the head of the plant.
Without this precaution, there would be too much
wood, and little fruit.
The pepper exported from Malabar, which was for¬
merly entirely in the hands of the Portuguefe, and was
afterwards divided between the Dutch, Britifh, and
French, amounted to about 10,000,000 weight. Betel,
or betle, is a fpecies of this genus. See Betel. It is
a creeping and climbing plant like the ivy 5 and its'
leaves a good deal refemble thofe of the citron, though
they are longer and narrower at the extremity. It
grows in all parts of India, but thrives befl: in moift
places. The natives cultivate it as we do the vine, pla¬
cing props for it to run and climb upon ; and it is a
common practice to plant it againfl: the tree which bears
the areca-nut.
At all times of the day, and even in the night, the
Indians chew the leaves of the betel, the bitternefs of
which is corre&ed by the areca that is wrapped up in
them. There is conftantly mixed with it the chinam,
a
(a) See a copious account of the mode, of cultivating pepper in Sumatra, in Mr Marfden’s Hi/lory of Sumatra,
or in the Hew Annual Regi/ler for 1783, p, 147.
2
i
L.ondon
Medical
Journal,
vol. viii.
part iii.
p. 276. 6cc
P I R [
a kind of burnt lime made of (hells. The rich frequent
ly add perfumes, either to gratify their vanity or their
fenfuality.
It would be thought a breach of politenefs among the
Indians to take leave for any long time, without prefent-
ing each other with a purle of betel. It is a pledge of
friendlhip that relieves the pain of abfence. No one
dares to fpeak to a fuperior unlefs his mouth is perfumed
with betel; it would even be rude to negledt this pre¬
caution with an equal. The women of gallantry are
the mod lavifh in the ufe of betel, as being a powerful
incentive to love. Betel is taken after meals j it is
chewed during a vifit j it is offered wdien you meet, and
when you feparate j in Ihort, nothing is to be done with¬
out betel. If it is prejudicial to the teeth, it afhfts and
ifrengthens the ftomach. At lead, it is a general fafhion
that prevails throughout India.
The piper mna/ago, or black pepper, and the piper
inequale, or long pepper of Jamaica, with fome other
fpecies, are indigenous, and known by the names of
joint wood, or peppery elders. The fird bears a fmall
fpike, on which are attached a number of fmall feeds
of the fize of mudard. The whole of the plant his the
exadt talle of the Eaft India black pepper. The long
pepper bu(h grows taller than the amalago. The leaves
are broad, fmooth, and fliining. The fruit is dmilar to
the long pepper of the (hops, but fmaller. The com¬
mon people in Jamaica feafon their meffes with the
black pepper. To preferve both, the fruit may be
(lightly fcalded when green, then dried, and wrapped in
paper. Perhaps hereafter they may be deemed worthy
of attention.
PIPRA, a genus of birds, of the order of pajjeres.
See Ornithology Index.
PIQUET, or Picket, a celebrated game at cards,
much in ufe throughout the polite world.
It is played between two perfons, with only 3 2 cards ;
all the duces, threes, fours, fives, and fixes, being fet
afide.
In reckoning at this game, every card goes for the
number it bears, as a ten for ten $ only all count cards
go for ten, and the ace for eleven : and the ufual game
is one hundred up. In playing, the ace wins the king,
the king the queen, and fo down.
Twelve cards are dealt round, ufually by two and
two 5 which done, the remainder are laid in the middle:
if one of the gamefters finds he has not a court card in
his hand, he is to declare he has carte blanche, and tell
how many cards he wall lay out, and defire the other
to difcard, that he may (how his game, and fatisfy his
antagonill that the carte-blanche is real; for which he
reckons ten.
Each perfon difcards, i. e. lays afide a certain num¬
ber of his cards, and takes in a like number from the
(lock. The firft of the eight cards may take three,
four, or five 5 the dealer all the remainder, if he
pleafes.
After difcarding, the elded hand examines what fuit
he has mod cards of; and reckoning hpw many points
he has in that fuit, if the other have not fo many in
that or any other fuit, he tells qne for every ten of
that fuit. He who thus reckons mod is faid to win the
.point.
The point being over, each examines what fcquences
4ie has of the fame fuit, viz. how many tierces, or fe-
Vol. XVI. Part II.
569 ] PIE
quences of threes, quartes or fours, quintes or fives, fix-
iemes, or fixes, &c. For a tierce they reckon three
points, for a. quarle four, for a quinte 15, for a fixieme
16, &c. And the feveral fequences are didinguiihed
in dignity by the cards they begin from : thus ace
king, and queen, are called tierce major ; king, queen,
and knave, tierce to a king; knave, ten, and nine,
tierce to a knave, &c. and the belt tierce, quarte, or
quinte, i. e. that which takes its defcent from the bed
card, prevails, fo as to make all the others in that
hand good, and dedroy all tho(e in the other hand.
In like manner, a quarte in one hand lets afide a tierce
in the other.
J he fequences over, they proceed to examine how
many aces, kings, queens, knaves, and tens, each
holds j reckoning for every three of any fort, three :
but here too, as in fequences, he that with the fame
number of threes has one that is higher than any the
other has, e. gr. three aces, has all his others made
good hereby, and his adverfary’s all fet afide. But four
of any fort, which is called a quator%e, ahvays fets
afide threl;.
All the game in hand being thus reckoned, the elded
proceeds to play, reckoning one for every card he plays
above a nine, and the other follows him in the fuit j and
the highed card of the fuit wins the trick. Note, un-,
lefs a trick be won with a card above a nine (except the
lad trick), nothing is reckoned for it, though the trick
ferves afterwards towards wanning the cards ; and that
he who plays lad does not reckon for his cards unlefs he
wins the trick.
The cards being played out, he that has mod tricks
reckons ten for wanning the cards. If they have tricks
alike, neither reckons any thing. The deal being fi-
niihed, and each having marked up his game, they pro¬
ceed to deal again as before, cutting afreih each time for
the deal.
If both parties be within a few points of being up, the
, carte-blanche is the fird thing that reckons, then the
point, then the fequences, then the quatorzes or threes,
then the tenth cards.
He that can reckon 30 in hand by carte-blanche,
points, quintes, &c. without playing, before the other
has reckoned any thing, reckons 90 for them j and
this is called a repique. If he reckons above 30, he
reckons fo many above 90. If he can make up 3c,
part in hand and part play, ere the other has told anv
thing, he reckons for them 60. And this is called
a pique. Whence the name of the game. He that
wins all the tricks, indead of ten, which i$ his right
for winning the cards, reckons 40. And this is called
a capot.
Mr de Moivre, wdio has made this game the obje£l
of mathematical invedigation, has propofed and folved
the following problems: 1. To find at piquet the pro¬
bability which the dealer has for taking one ace or more
in three cards, he having none in his hand. He con¬
cludes from his computation, that it is 29 to 28 that
the dealer takes one ace or more. 2. To find at piquet
the probability which the elded has of taking an ace
or more in five cards, he having no ace in his hand.
Anfwer : 23210 91, or 5 to 2, nearly. 3. To find
at piquet the probability which the elded hand has of
taking an ace and a king in five cards, he having none
■in his hand. Anfwer: the odds ^craind the elded hand
' O
4 C taking
Piquet..
P I II Is
Piquet, taking an ace and a king are 531 to 315. or 21 to 20
1Jira' , nearly. 4. To find at piquet the probability of having
12 cards dealt to, without king, queen, or knaves,
which cafe is commonly called earies-bianchcs. An-
fvver j the odds againft cartes-blanches are 1791 to 1
nearly. 5. To find how many different lets, effential-
ly different from one another, one may have at piquet
before taking in. Anfwer j 28,967,278. This num¬
ber falls fhort of the fum of all the diftindt combina¬
tions, whereby 12 cards may be taken out of 32, this
number being 225,792,840 •, but it muff be confidefed
that in that number feveral fets of the fame import,
but differing in fuit, might be taken, which would not
introduce an efTentiaf difference among the fets. The
fame author gives alfo fome obfervations on this game,
which he had from an experienced player. See Doc¬
trine of Chances, p. 179, &c. M. de Monmort has
treated of piquet in His Analyse des Jeux de Hazard,
p. 162.
PIKA, is a name by which a variety of foreign
fiflies are diftinguifhed. The pira-aca is a little horned
fifh of the Weft Indies, called by Clufius and others
the monoceros or unicorn fjh. Thepira acangata is the
name of a Brafilian fifh, which refembles the perch
both in fize and fhape. It feldom exceeds four or five
inches in length 5 its mouth is fmall; its tail fork¬
ed. On the back it has only one long fin, which is
supported by rigid and prickly fpines. This fin it can
deprefs at pleafure, and fink within a cavity made for
it in the back. Its feales are of a filvery wdrite colour 5
it is wholefome and well tailed. Pira bebe is the name
of the milvus, or kite-fifh. Pira-coaba is an American
fifh of the truttaceous kind, of a very delicate flavour.
It grows to the length of 12 inches 5 its nofe is point¬
ed, and its mouth large, but without teeth j the up¬
per jaw is longer than the under one, and hangs over
like a cartilaginous prominence ; its eyes are very
large, and its tail is forked ; under each of the gill fins
there is a beard made of fix wdrite filaments, and covered
with filvery feales. Pira jiirumenheca is a Brafilian fiflr,
otherwife called bocca mollc. It lives in the muddy bot¬
tom of the American feas, and is a long-bodied not flat¬
ted filh. It grows to a great fize, being found nine, and
lometimes even ten or eleven, feet long, and twro feet
and a half thick. It has one long fin on the back, the
anterior part of which is thin and pellucid. There is
alfo a cavity on the back, as in the pira acangata, into
which the fin can be deprefled at pleafure j the tail
is not forked, and the feales are all of a filvery co¬
lour and brightnefs. The fifh is very well tafted j
the pira pixanga is another Brafilian fifh of the turdus
or wrafie kind, and called by fome the gutvifeh. It
is generally about four or five inches long } its mouth
is pretty large, and furnifhed with very fmall and very
fharp teeth ; its head is final], but its eyes are large and
prominent, the pupil being of a fine turquoife colour,
and the iris yellow and red in a variety of {hades. The
coverings of the gills end in a triangular figure, and are
terminated by a fhort fpine or prickle 5 its feales are
very fmall, and fo evenly arranged, and clofely laid on
the flefh, that it is very finooth to the touch •, its tail is
rounded at the end ; its whole body, head, tail, and fins,
are of a pale yellow colour, variegated all over w'ith
’tccry beautiful blood-coloured fpots j thefe are round,
'O ) P I R
and of the bignefs of hemp-feed on the back and Tides, Pira,
and fomething larger on the belly ; the fins are all fpot- Plneus-
ted in the fame manner, and are all marked with an edge v" " '
of red. It is caught among the rocks, and about the
fhores, and is a very well tafied fiih. Piranha is an
American fifh, more generally known by the name pi-
raya. Piraquiba, or ipiraquiba, is the name of a fifh
originally Brafilian, which fome waiters apply to the
remora or fucking fjh.
P1KALUS PORTUS, in Ancient Geography, a celebra¬
ted port to the weft of Athens, confifting naturally of
three harbours or bafons, (Thucydides) 5 which lay ne¬
glected, till Themiftocles put the Athenians on making
it a commodious port, (Nepos) *, the Phalerus, a fmall
port, and not far from the city, being wdiat they ufed
before that time, (Paufanias, Nepos). Piraeus w7as ori¬
ginally a village of Attica, (Paufanias) ; an ifland,
(Strabo) •, and though diftant 40 ftadia from Athens,
was joined to it by two long walls, (Thucydides), and
itfelf locked or walled round, (Nepos): A very com¬
modious and fafe harbour. The whole of its compafir
wTas 60 ftadia, including the Munichia. Not far from
the Piraeus flood the fepulchre of Themiftocles j whither
his friends conveyed his bones from Magnefia, into the
Hither Afia, (Cicero, Plutarch, Paufanias). The tn-Chandler's
trance of the Piraeus is narrow, and fonned by two rocky ^jaTels m
points, one belonging to the promontory of Eelicn, the ^?
other to that of Alcimus. Within were three ftations1
for {hipping •, Kantharus, fo named from a hero •, Aphro-
difimn, from, a temple of Venus *, and Zea, the refort of
vefiels laden with grain. By it was a demos or borough
town of the fame name before the time of Themiftocles,
who recommended the exchanging its triple harbour for
the finglc one of Phalerum, both as more capacious and
as better fitnated for navigators. The wall was begun
by him when archon, in the fecond year of the 7 5th
Olympiad, 477 years before Chrift •, and afterwards he
urged the Athenians to complete it as the importance of
the place deferved. This whole fortification was of
hewn ftone, without cement or other material, except
lead and iron, which were ufed to hold together the ex¬
terior ranges or facings. It was fo wide that loaded
carts could pafs on it in different direcHons, and it was
40 cubits high, which w7as about half what he had de¬
li gned.
The Piraeus, as Athens flourifhed, became the com¬
mon emporium of all Greece. Hippodamus an architect,
celebrated, befides other monuments of his genius, as the
inventor of many improvements in houfe-building, was
employed to lay out the ground. Five porticoes, which
uniting formed the Long Portico, w7ere erefted by the
ports. Here was an agora or market-place, and, farther
from the fea, another called Hippodanua. By the vef-
fels wrere dwellings for the mariners. A theatre wras
opened, temples wTere raifed, and the Piraeus, which
furpaffed the city in utility, began to equal it in dignity.
The cavities and windings of Munichia, natural and ar¬
tificial, were filled with houfes; and the whole fettle-
ment, comprehending Phalerum and the ports of the
Piraeus, wdth the arfenals, the ftorehoufes, the famous
armdury of wdiich Philo wTas the architedt, and the fheds
for 300, and afterwards 400, triremes, refembled the
city of Rhodes, which had been planned by the fame
Hippodamus. The ports, on the commencement of the
Peloponnefian
FIR [ 571 ] P I R
Pnaeus, Peloponnefian war, were fecured with chains. Cen-
p;rar}'' , tinels were ftationed, and the Piraeus was carefully
guarded.
The Piraeus was reduced with great difficulty by Syl-
la, who demoliffied the walls, and let fire to the ar¬
moury and arfenals. In the civil war it was in a de-
fencelefs condition. Calenus, lieutenant to Caefar, fei-
zed it, invefted Athens, and ravaged the territory.
Strabo, who lived under the emperors Auguftus and Ti¬
berius, obferves, that the many wars had deftroyed the
long walls, with the fortrefs of Munychia, and had con-
traded the Piraeus into a fmall fettlement by the ports
and the temple of Jupiter Saviour. This fabric was then
adorned with wonderful pidures, the works of illuftrious
artifts, and on the outfide with ftatues. In the fecond
century, befides houfes for triremes, the temple of Jupi¬
ter and Minerva remained, with their images in brafs,
and a temple of Venus, a portico, and the tomb of The-
miftocles.
The port of the Piraeus has been named Porto Lione,
from the marble lion feen in the chart, and alfo Porto
Dracco, The lion has been defcribed as a piece of ad¬
mirable fculpture, 10 feet high, and as repofing on its
hinder parts. It was pierced, and, as fome have conjec¬
tured, had belonged to a fountain. Near Athens, in
the way to Eleufis, was another, the pofture couchant ;
probably its companion. Both thefe were removed to
Venice by the famous general Morofini, and are to be
feen there before the arfenal. At the mouth of the port
are two ruined piers. A few veffels, moRly fmall craft,
frequent it. Some low land at the head feems an in-
croachment on the water. The buildings are a mean
cuftomhoufe, with a few ffieds 5 and by the ffiore on
the eaft fide, a warehoufe belonging to the French 5 and
a Greek monaftery dedicated to St Spiridion.- On the
oppofite fide is a rocky ridge, on which are remnants of
the ancient wall, and of a gateway towards Athens.
By the water-edge are veftiges of building; and going
from the cuftomhoufe to the city on the right hand,
traces of a fmall theatre in the fide of the hill of Muny¬
chia.
PIRACY, the crime of robbery and depredation up¬
on the high feas.
By the ancient common law, piracy, if committed by
a fubjeft, was held to be a fpecies of treafori, being con¬
trary to his natural allegiance; and by an alien, to be
felony only: but nove, fince the ftatute of treafons,
25 Edw. III. c. 2. it is held to be only felony in a fub-
jefl. Formerly it was only cognizable by the admiralty
courts, which proceed by the rules of the civil law.
But, it being inconfiftent with the liberties of the na¬
tion, that any man’s life ffiould be taken away, unlefs
by the judgement of his peers, or the common law of the
land, the ftatute 28 Hen. VIII. c. 15. eftablifhed a new
jurifdiftion for this purpofe ; which proceeds according
to the courfe of the common law.
The offence of piracy, by common law, confifts in
committing thofe afts of robbery and depredation upon
the high feas, which, if committed upon land, would
have amounted to felony there. But, by ftatute, fome
other offences are made piracy alfb : as, by ftatute 11
and 12 W. III. c. 7. if any natural-born fubjeft com¬
mits any aft of hoftility upon the high feas, againft others
of his majefty’s fubjefts, under colour of a commiffion
from any foreign power j this, though it would only be
an aft of war in an alien, (hall be conftrued piracy in a Piracy,
fubjeft. And farther, any commander, or other feafar- '
ing perfon, betraying his truft, and running away with " _¥
any thip, boat, ordnance, ammunition, or goods ; or
yielding them up voluntarily to a pirate 5 or confpiring
to do thefe afts \ or any perfon affaulting the command¬
er of a veffel, to hinder him from fighting in defence of
his ftiip ; or confining him, or caufing or endeavouring
to caufe a revolt on board ; ffiall, for each of thefe of¬
fences, be adjudged a pirate, felon, and robber, and
flrall fuffer death, whether he be principal, or merely
acceffory by fetting forth fuch pirates, or abetting them
before the faft, or receiving or concealing them or their
goods after it. And the ftatute 4 Geo. I. c. 11. ex-
prefsly excludes the principals from the benefit of cler¬
gy. By the ftatute 8 Geo. I. c. 24. the trading with
known pirates, or furniftung them with ammunition, or
fitting out any veffel for that purpofe, or in anywife con-
fulting, combining, confederating, or correfponding with
them ; or the forcibly boarding any merchant veffel,
though without feizing or carrying her off, and deftroy-
ing or throwing any of the goods overboard; fnall be
deemed piracy : and fuch acceffories to piracy as are dc-
feribed by the ftatute of King William are declared to
be principal pirates •, and all pirates convifted by virtue
of this aft are made felons without benefit of clergy.
By the fame ftatutes alfo, (to encourage the defence of
merchant-veffels againft pirates), the commanders or fea-
men wounded, and the widows of fuch feamen as are
fiain, in any piratical engagement, fliall be entitled to
a bounty to be divided among them, not exceeding one-
fiftieth part of the value of the cargo on board .- and
fuch wounded feamen ftiall be inlitled to the penfion of
Greenwich hofpital •, which no other feamen are, except
only facli as have ferved in a flrip of war. And if the
commander ffiall behave cowardly, by not defending the
(hip, if ffie carry guns or arms; or ffiall difeharge the
mariners from fighting, fo that the flap falls into the
hands of pirates: fuch commander ftiall forfeit all his
wages, and fuffer fix months imprifonment. Laftly, bv
ftatute 18 Geo. II. c. 30. any natural-born fubjeft or
denizen, who in time of war ffiall commit hoftilities at
fea againft any of his fellow-fubjefts, or {hall affift an
enemy on that element, is liable to be tried and convift¬
ed as a pirate.
PIRATit, (vrugiihs, Gr.) ; a fea-robber, or an arm¬
ed ffiip that roams the feas without any legal commif¬
fion, and feizes or plunders every veffel {he meets indif-
criminately, -whether friends or enemies.
The colours ufually difplayed by pirates are faid to be
a black field, with a death’s head, a battle-axe, and
hour-glafs. The laft inftrument is generally fuppofed to
determine the time allowed to the prifoners, whom they
take, to confider whether they will join the pirates in
their felonious combination, or be put to death, which
is often perpetrated in the moft cruel manner.
Among the moft celebrated pirates of the nprth is re¬
corded Alvilda, daughter of a king of the Goths named
Syparaus. She embraced this occupation to deliver her-
felf from the violence impofed on her inclination, by a
marriage with Alf, fon of Sigarus king of Denmark.
She dreffed herfelf as a man ; and compofed her band of
rowers, and the reft of her crew, of a number of young
women attired in the fame manner. Amongft the firft
of her cruizes, flie touched at a place where a company
C 2 of
P I R [ 572 ] FIR
Pirate of pirates bewailed the death of their captain. The
p ftrangers were captivated with the agreeable manners of
   Alvilda, and choft her for their chief. Ey this rein¬
forcement fne became fo formidable upon the fea, that
Prince Alf came to engage her. She fuftained his at¬
tacks for a confiderable time : but, in a vigorous aftion,
Alf boarded her veffel, and having killed the greatetl
part of her crew, feized the captain, namely herfelf j
whom neverthelefs he knew not, becaufe the princefs
liad a cafque w7hich covered her vifage. Being mafler
ofherperfon, he removed the cafque j and in fpite of
lier difguife, inftantly recognized her, and- oifered her
his hand in wedlock.
PIRENE, (Pliny) 5 a fountain facred to the mufes,
fpringing below the top of the Acrocorinthus, a high
and ifeep mountain which hangs over Corinth. Its wa¬
ters were agreeable to drink, (Paufanias) j extremely
clear, (Strabo) 5 very light, (Athenseus) j and pale,
(Perfius) : having relation either to the grief of Pirene,
mother of Cenchrea, from whofe tears this fountain
arofe, (Paufanias) 5 or to the palenefs brought on by the
too eager purfuits of the mufes.
PIROMALLI, Paul, a dominican of Calabria, was
fent a miffionary into the ead. He remained a long
time in Armenia, where he had the happinefs to bring
back to the church many fchifmatics and Eutycheans,
and the patriarch himfelf, wffio had before thrown every
obdacle in his way. He afterwards paffed into Georgia
and Perfia, then into Poland, in quality of Pope Ur¬
ban VIII.’s nuncio, in order to appeafe the didurbances
which had been occafioned there by the difputes of the
Armenians, who were very numerous in that country.
Piromalli reunited them in the profeffion of the fame
faith, and obfervance of the fame ceremonies. In his
return to Italy, he was taken by fome corfairs who car¬
ried him prifoner to Tunis. As foon as he was ranfomed,
he went to Rome, and gave an account of his miffion to
the pope, wffio conferred upon him fome dgnal marks of
his edeem. His holinefs entruded him with the revifal
of an Armenian Bible, and fent him again into the ead,
where he was promoted, in 1695, to bilhopric of
Naffivan. After having governed that church for nine
years, he returned to Italy, and took the charge of the
church of Bafignano, wffiere he died three years after in
1667. His charity, his zeal, and other virtues, did ho¬
nour to the Epifcopal office. There are extant of his
writings, 1. Some works of Controverfy and Theology.
2.. Two Dictionaries j the one a Latin-Perfian, and the
other an Armenian-Latin. 3. An Armenian Grammar.
4. A Directory, which is of great ufe in correcting Ar¬
menian books. All thefe works equally didinguiih him
for virtue and for learning.
PIRON, Alexis, a French poet, was born at Dijon
in July 1689, where his father wras an apothecary, and
where he palled more than 30 years in idle and dedruc-
tive diffipation. Fie was at length obliged to quit the
place of his nativity, in order to avoid the reproaches of
his fellow citizens, on account of an ode which he had
written, and which gave great offence. His relations
not being able to give him much affidance, he fupport-
cd himfelf at Paris by means of his pen, the drokes of
which were as beautiful and fair as thofe of an engraver.
He lived in the houfe of M. de Bellifle as his fecretary,
and afterwards with a financier, wffio did not know that
he had a inan of genius under his roof. His reputation
as a writer commenced with fome pieces which he pub-
luffied tor the entertainment of the populace, and which
fliowed drong marks of original invention ; but what
fully edabliihed his character in this way was his come¬
dy intitled Metromany, which was the bed that had ap¬
peared in France fince Regnard’s Gameder. This per¬
formance, in five aCts, wTell conducted, replete with ge¬
nius, wit, and humour, was aCted with the greated fuc-
cefs upon the French dage in 1738. The author met
with every attention in the capital which was due to a
man of real genius, and whofe daffies of wut were inex-
haudible. We fhall infert a few anecdotes of him,
wffiich wall ferve to diow his charafler and turn of mind.
In Burgundy the inhabitants of Beaune are called the
AJfes of Beaune. Piron often indulged his fatirical dif-
polition at their expence. One day as he was taking a
wfalk in the neighbourhood of that city, he diverted him¬
felf with cutting down all the thidles which he met with.
When a friend afked him his reafon for doing fo, he re¬
plied, J^ai a me plaindre des Beaunois ; je leur coupe ie r
viv/'es, i. e. “ I am forry indeed for the Beaunians; for
I am cutting down their food.” Being told again that
thefe people would certainly be revenged of him,
Alle%, (fays he) A/lez : je ne crains point leur impuif-
fant couroux ;
Et quand je ferois feu!, je les batterois tons.
“ Get you gone, get you gone : I fear not their feeble
revenge •, for though alone, I ffiould beat them all.”
Going into a theatre one- time where a play was adling,
'he alked what it was ? The Cheats of Scapin, gravely
replied a young Beaunian. “ Ah ! Sir, (fays Piron,
after thanking him), I took it to be the Cheats of
Oreftes.” In the time of the play, fome body addreffes
the company with “ Silence there, gentlemen, we don’t
hear.” “ It is not at leaf! (cried Piron) for wrant of
ears.” A biffiop one day afked Piron, during the dif¬
putes about Janfenifm, “ Did you read my mandate, Mr
Piron ?” No, my lord ; and you The converfation
Turning very warm, the biffiop reminded him of the di-
fiance which birth and rank had put betiveen them.
“ Sir (fays Piron), I have plainly the fuperiority over
you at this moment ; for I am in the right, and you are
in the wrong.”—Voltaire’s Semiramis did not meet with
a very favourable reception the firft time it was adled.
The author finding Piron behind the fcenes, afked him
what he thought of his performance ? “ I think (replied
he) you w ould have been pleafed that I had been the
author of it.” The performer of the charadler Ferdi¬
nand Cortez (the title of one of Piron’s tragedies) hav¬
ing requefled tome corredlions to be made on the play
the firfl time it wras added.. Piron fired at the word cor-
reBions. The player, who was deputed to wait upon
the author with this requefl, cited the example of Vol¬
taire, who corredled fome of his pieces in order to gra¬
tify the taffe of the public. “ The cafes are widely dif¬
ferent (replied Piron)-, Voltaire works in chequer-work,
and I caff in brafs” If this anfwer be not very modeft,
we muff allow that it does not want wit. He thought
himfelf, if not fuperior, at leaf! equal to Voltaire.
Some perfon congratulating him on having compofed
the befl comedy of this age, he anfwered, with more
franknefs than modefly, “ Add too, and the befl tra-
gedy.”
PIS [ 573 ] PIS
Piron, gedy.” The following verfes are well known, in which
Pi fa. he fayS ;
En deux mots voulez-vous diftinguer et connoitre
Le rimeur Dijonnois et le Parifien ?
Le premier tie fut rien, et tie voulut rien etre ;
1?autre voulut tout etre, et ne fut prefque rien.
We fee by thefe different traits that Piron had a fuf-
ficient flock of felf-conceit. What helped to increafe
it, and make him fancy himfelf fuperior to the mofl ce¬
lebrated of his contemporaries, was, that his company,
on account of his original humour, of which he had an
uncommon fhare, was more courted than that of Vol¬
taire, who was otherwife too lively, too captious, and
crabbed. But thofe who have favoured us with an ac¬
count of his many witticifms in converfation, would have
done more honour to his memory if they had paffed over
fuch as were either indecent or infipid. A thing often
pleafes over a glafs of wine, which will not give the
fame fatisfa&ion when it is repeated, efpecially if, in re¬
peating it, you want to make it appear of fome import¬
ance. Be that as it may, Piron’s mifchievous ingenuity
was partly the caufe which excluded him from the
French Academy.—“ I could not (faid he) make thirty-
nine people think as I do, and I could lefs think as
thirty-nine do.” He called that celebrated fociety very
unjuftly les invalides du bel efprit, “ the invalids of wit j”
and yet he often endeavoured to be one of thofe inva¬
lids. His death was haflened by a fall which he got a
little before. He died the 2ift of January 1773, at the
age of 83. He had prepared for himfelf the following
epitaph, in the way of an epigram :
Ci git Piron, qui ne fut rien,
Pas me me academicien.
Here lies Piron, who was nothing, not even an aca¬
demician.”
His wife Maria Therefa Quenandon, who died in
1751, he defcribes as a fweet and moft agreeable com¬
panion. They lived together for feveral years ; and no
hufband ever difcharged his duty with more fidelity and
attention.
A colle&ion of his works appeared in 1776, in 7 vols
8vo, and 9 vols 1 2mo. The principal pieces are, The
School of Fathers; a comedy afted in 1728 under the
title of Ungrateful Sons. Callifthenes •, a tragedy, the
fub]'e£l of which is taken from Juftin. The Myfterious
Lover, a comedy. Guftavus and Ferdinand Cortez, two
tragedies •, fome fcenes of which difcover an original ge¬
nius, but the verfification neither pleafes the ear nor af-
fe£ls the heart. Metromany, a comedy. The Courfes
of Tempe, an ingenious paftoral, in which the manners
both of the town and country are pleafantly drawn.
Some odes, poems, fables, and epigrams. In this laft
kind of poetry he was very fuccefsful, and he may be
placed after Marot and Rouffeau. There was no occa-
fion for loading the public with 7 vols of his works; the
half of that number might have fufficed. For, excepting
Metromany, Guftavus, the Courfes of Tempe, fome
odes, about 20 epigrams, three or four fables, and fome
epiftles, the reft are but indifferent, and have no claim
to any extraordinary merit.
PISA, a large town of Tufcany in Italy, fituated on
the river Arno, ^2 miles from Florence. It was a fa¬
mous republic, till fubdued, firft by the duke of Milan,
and then by the Florentines in the year 1406. Before
it loft its freedom, it is faid to have contained near
150,000 inhabitants, but now it has not above 16,000
or 17,000. It was founded, we are told, by the Pilaus
of Peloponnefus, and after-wards became one of the 12
municipia of Tufcany. Its neighbourhood to Leghorn,
which is now the chief port in the Mediterranean,
though formerly of little or no note for trade, has con¬
tributed greatly to the decay of Pifa, which, however,,
begins to lift up its head again, under the aufpices of the
prefent grand duke, who has made it his winter refi-
dence. Between Pifa and Leghorn is a canal 16 Ita¬
lian miles in length.—Its territory is very fruitful ; a-
bounding in corn, wine, and fruit, and fine cattle. The
houfes are well built, and the ftreets even, broad, and
well paved} but in many places overrun with grafs.
The univerfity is well endowed, and has able profeffors,
but is not in a very flourilhing condition. The exchange
is a ftately ftru6ture, but little frequented. The grand
duke’s galleys are built, and commonly ftationed here.
This city is alfo the principal refidence of the order ol
St Stephen, and the fee of an archbifhop. The cathe¬
dral, a large Gothic pile, contains a great number of
excellent paintings and other curiofities. This church
is dedicated to St Mary 5 is very advantageoufty fituated
in the middle of a large piazza, and built out of a great
heap of wrought marble, fuch as pillars, pedeftals, capi¬
tals, cornices, and architraves, part of the fpoils which
the Pifans took in their eaftern expeditions, when the re¬
public was in a flourifhing condition. The roof is fup-
ported by 76 high marble pillars of different colours, and
finely gilt. Both the church and the cupola are covered
with lead. The choir is painted by good hands, and
the floor is mofaic work. The brazen doors are cu-
rioufly wrought with the hiftory of the Old and New
Teftament, by Bonanno, an ancient ftatuary. The
chapel of St Rainerius is richly adorned with gilt me¬
tals, columns of porphyry, and fine paintings. In the
middle of the nave of the church you fee two brazen
tombs, raifed upon pillars. The marble pulpit was car¬
ved by John Pifano, and the choir by Julian da Ma-
jana. Joining thereto is the altar, over which is prefer-
ved a hollow globe or veffel of marble, wherein they
kept the facrament for the new baptized, according to
the opinion of Father Mabillon. In the fquare before
the church, you fee a pillar upon which is the meafure
of the ancient Roman talent. In the fame fquare with
the dome, ftands the baptiftery, a round fabric fiipported
by ftately pillars, and remarkable for a very extraordi¬
nary echo.
On the north fide of the cathedral is the burying-
place, called Campo Santo, being covered with earth
brought from the Holy Land. This burying-place is
inclofed with a broad portico, well painted, and paved
with grave ftones. Here are a great many ancient tombs,
among the reft that of Beatrix, mother of the counteis
Mathilda, with marble baffo-relievos, -which the Pifans
brought from Greece, where you fee the hunt of Mele¬
ager, which aflifted Nicholas of Pifa in the reftoration
of fculptiire. The walls of the Campo Santo are paint¬
ed by the beft mafters of their times. Giotto has drawn
fix hiftorical pieces of Job •, and Andrea Orgagna has
given a fine piece of the laft judgement. Under the
portico there is a decree of the city, ordering the inha¬
bitants to wear mourning a year for the death of Ctefar.
Near.-
P I s
Pi fa
. I) .
Pifcidia.
Near tlie church you fee a fteepie in the form of a cylin¬
der, to which you afcend by 153 fteps 5 it inclines 15
_ feet on one fide, which fome afcribe to art, but others
to the finking of the foundation. Its inclination is fo
great that a plumb-line let fall from the top touches the
ground at the diftance of almoft 15 feet from the bot¬
tom. It was built by John of Infpruck and Bonanno of
Pifa, in 1174. Near this fteepie is a fine hofpital, de¬
pendent on that of St Maria Nuova in Florence.
The fteepie of the church of the Auguftinians is alfo
very fine, being an o&agon, adorned with pillars, and
built by Nicholas of Pifa. In the great market-place
there is a ftatue of Plenty, by Pierino da Vinci. In the
church of St Matthew, the painting of the ceiling by
the brothers Melani, natives of this city, is an admired
performance. The church of the knights of St Stephen,
decorated with the trophies taken from the Saracens, is
all of marble, with marble fteps, and a front adorned
with marble ftatues. In the fquare there is a ftatue of
Cofmo I. upon a very fine pedeftal. Contiguous to the
church is the convent or palace of the knights, which
is worth feeing, as alfo the churches Della Madonna and
Della Spina; ihe laft of which wras built by a beggar,
whofe figure you may fee on the outfide of the wall. It
is pretended that one of the thorns of the crown which
was placed on our Saviour’s head is preferved here. Be-
longing to the univerfity there is a great number of col¬
leges, the chief of wduch is the Sapienza, where the pro-
feifors read their public lectures 5 next to which are the
colleges Puteano, Ferdinando, Ricci, and others. Be-
fides the public palace, and that of the grand duke,
there are feveral others with marble fronts, the fineft of
wTich is that of Lanfranchi, which, with the reft along
the banks of the Arno, makes a very fine appearance.
There is here a good dock, where they build the galleys,
which are conveyed by the Arno to Leghorn. They
nave a famous anuedudl in this torvn, confifting of 5000
arches, which conveys the water from the hills at five
miles diftance. 1 his water is efteemed the beft in Italy,
and is carried in flafks to Florence and Leghorn. The
neighbouring country produces great ftore of corn and
wine, but the latter is not much efteemed. They have
very good butter in this neighbourhood, which is a
fcarce commodity in Italy. The city for its defence has
a moat, walls, a caftle, fort, and citadel ; the laft of
which is a modern wrork. I he Arno is of a confiderable
breadth here, and has three bridges over it, one of them
of marble : two leagues below the town it falls into the
lea. The phyfic-garden is very fpacious, contains a
great number of plants, and is decorated with water-
works: over the door leading into it are thefe words,
Hie Argus fed non Bnareus efo : i. e. “ Employ the
eyes of Argus, but not the hands of Briareus. The air
is Laid to be unwholefome here in fummer, on account
of the neighbouring morafles. Many buffaloes are bred
in the neighbouring country, and their flefli is common¬
ly eaten. Between Pifa and Lucca are hot baths. E.
Long. 10. 17. N. Lat. 43. 43.
PISCARY , in our ancient ftatutes, the liberty of
fifiring in another man’s waters.
PISCES, \n Ajlronomy, the 12th fign or conftella-
tion of the zodiac.
PISCIDIA, a genus of plants belonging to the diadel-
phia clafs. See Botany Index.
PISCIDIA Erythrina, or Dogwood-tree, is employed to
3
t 574 1
P I S
intoxicate fifti. For this purpofe, the bark is pounded Pifcina,
fmall, put into bags, and foaked in fait water. The juice, iFlfiftrahls.
which is of a red colour, makes the fifii ftupid, fo that
they are eafily taken.
PISCINA, in antiquity, a large bafon in a public
place or fquare, where the Roman youth learned to
fwim : and which was furrounded with a high wall, to
prevent filth from being thrown into it.—This word is
alfo ufed for a lavatory among the Turks, placed in
the middle court of a mofque or temple, where the
Muffulmans wafli themfelves before they offer their
prayers.
PlSISTRATUS, an Athenian who early diftin-Bib/iot/je-
guifiied himfelf by his valour in the field, and by hiscal Ci’a.fica,
addrefs and eloquence at home. After he had render-
ed himfelf the favourite of the populace by his libera-6^'
lity and by the intrepidity ivith which he had fought
their battles, particularly near Salamis, he refolved to
make himfelf mafter of his country. Every thing feem-
ed favourable to his ambitious views; but Solon alone,
who was then at the head of affairs, and who had late¬
ly enforced his celebrated laws, oppofed him, and dif-
covered his duplicity and artful behaviour before the
public aftembly. Pififtratus was not diiheartened by
the meafures of his relation Solon, but he had recourfe
to artifice. In returning from his country-houfe, he
cut himfelf in various places; and after he had expofed
his mangled body to the eyes of the populace, deplo¬
red his misfortunes, and accufed his enemies of at¬
tempts upon his life, becaufe he -was the friend of the
people, the guardian of the poor, and the reliever of
the oppreffed, he claimed a chofen body of 50 men.
from the populace to defend his pevfon in future from
the malevolence and the cruelty of his enemies. The
unfufpefting people unanimoufly granted his requeft,
though Solon oppofed it with all his influence 5 and
Pififtratus had no fooner received an armed band on
whofe fidelity and attachment he could rely, than he
feized the citadel of Athens, and made himfelf abfo-
lute. The people too late perceived their credulity j
yet, though the tyrant was popular, two of the citi¬
zens', Megacles and Lycurgus, confpired together a-
gainft him, and by their means he was forcibly eje6I-
ed from the city. His houfe and all his effefts were
expofed to fale j but there was fouixl in Athens only
one man who would buy them. The private diffen-
fions of the friends of liberty proved favourable to the
expelled tyrant; and Megacles, who wTas jealous of Ly¬
curgus, fecretly promifed to reftore Pififtratus to all his
rights and privileges in Athens, if he w-ould marry his
daughter. Pififtratus confented 5 and by the afliftance
of his father-in-law, he was foon enabled to expel Ly¬
curgus, and to re-eftablifti himfelf. By means of a wo¬
man called Plya, whofe ftiape was tall, whofe features
wrere noble and commanding, he impofed upon the
people, and created himlelf adherents even among his
enemies. Phya wras conducted through the ftreets of
the city, and (bowing herfelf fubfervient to the arti¬
fice of Pififtratus, (lie w7as announced as Minerva, the
goddefs of wufdom, and the patronefs of Athens, who
was come down from Heaven to re-eftabli(h her favou¬
rite Pififtratus in a power which was fanftioned by the
will of Heaven, and favoured by the affection of the
people. In the midft of his triumph, horvever, Pifi¬
ftratus found hiflifelf unfupported } and fome time after,
when
PIS [ :
.Pifirira’ ns.^ when he repudiated the daughter of Megacles, he found
that not only the citizens, but even his very troops,
were alienated from him by the influence, the intrigues,
and the bribery of his father-in-law. He fled from
Athens where he no longer could maintain his power,
and retired to Euboea. Eleven years after he was
drawn from his obfcure retreat, by means of his fon
Hippias, and he was a third time received by the
.people of Athens as their mafter and fovereign. Upon
this he facrificed to his refentment the friends of P4e-
gacles, but he did notlofe fight of the public good, and
while he fought the aggrandizement of his family, he did
not neglefk the dignity and the honour of the Athenian
name. He died about 528 years before the Chriitian
era, after he had enjoyed the fovereign power at Athens
for 33 years, and he -was fucceeded by his (bn Hippar¬
chus. Pififtratus claims our admiration for his juflice,
his liberality, and his moderation. If he was dreaded
and detefted as a tyrant, the Athenians loved and refpeft-
ed his private virtues and his patriotifm as a fellow'-
citizen : and the opprobiium which generallv falls on
his head may be attributed not to the feverity of his
adminidration, but to the republican principles of the
Athenians, who hated and exclaimed againll the mo¬
deration and equity of the mildeft fovereign, while
they flattered the pride and gratified the guilty defires
of the mod tyrannical of their fellow fubjects. Pifi-
dratus often refufed to punifli the infolence of his ene¬
mies 5 and when he had one day been virulently accu-
led of murder, rather than inflict immediate punifh-
ment upon the man who had criminated him, he went
to the areopagus, and there convinced the Athenians
that the accufations of his enemies were groundlefs,
and that his life w^as irreproachable. It is to his la¬
bours that we are indebted for the prefervation of the
poems of Homer; and he w’as the fird, according to
Cicero, who introduced them at Athens in the order
in which they now dand. He alfo edablifhed a public
library at Athens; and the valuable books which he
had diligently colle&ed were carried into Perfia wdien
Xerxes made himfelf mader of the capital of Attica.
Hipparchus and Hippias the fons of Pifidratus, who
had received the name of Pifijlratidce, rendered them-
felves as illudrious as their father 5 but the flames of li¬
berty were too powerful to be extinguifhed. The Pi-
dftratidae governed with great moderation, but the
name of tyrant or fovereign w>as infupportable to the
Athenians. Two of the mod refpeftable of the citi¬
zens, called Harmodius and Ariflogiton. confpired againft
them, and Plipparchus -was difpatched in a public af-
fembly. This murder w'as not, however, attended
with any advantages ; and though the two leaders of
the confpiracy, who have been celebrated through eve¬
ry age for fheir patriotifm, were fupported by the
people, yet Hippias quelled the tumult by his uncom¬
mon firmnefs and prudence, and for a while preferved
that peace in Athens which his father had often been
unable to command. This was not long to continue.
Hippias was at lad expelled by the united efforts of
the Athenians and of their allies, and he left Attica,
when he found himfelf unable to maintain his power
and independence. The red of the family of Pifidra¬
tus followed him in his banifhment 5 and after they had
refufed to accept the liberal offers of the princes of
ThelTaly. and the king of Macedonia, who wilhed them
175 ] PIS
to fettle in their refpe&ive territories, the Piiidratidm Pififtratus
retired to Sigaeum, which their father had in the dim- |l
mit of his power conquered and bequeathed to his, Plfo‘ .
poderity. After the banilhment of the Pifidratidm,
the Athenians became more than commonly jealous of
their liberty, and often facrificed the mod powerful of
their citizens, apprehenfive of the influence which po¬
pularity and a well-diretded liberality might gain among
a fickle and uniettled populace. The Pilldratidse were
banifhed from Athens about 18 years after the death of
Pifidratus.
1 1SMIRES, or Axts, are a kind of infeids very
common in Africa ; of which there is fo great a variety,
and fuch innumerable fwarms, that they dedroy not on¬
ly the fruits of the ground but fometimes even men and
beads in fo little time as one fingle night j and would,
without all doubt, prove more fatally dedru&ive to the
inhabitants, were they not fb happily dedroyed by a
proportionable number of monkeys and other animals,
who greedily devour them. The far greater part of the
vad continent of Africa is afflifted with thefe and fome
ether grievous plagues, and particularly with the horrid
vifitation of locuds, which feldom fail a year of laying
wade fome of the provinces.
PISO, Lucius Calpurnius, furnamed jFW/§7 on ac¬
count of his frugality, was defeended of the illudrious
family of the Pifos, which gave fo many great men to
the Roman republic. He was tribune of the people in
the year 149 before Chrid, and afterwards conful.
During his tribunefhip, he publifhed a law againd the
crime of concuffion or extortion, intitled Lex Colpuvnui
depecuniis repetundis. He happily ended the war in
Sicily. To reward the fervices of one of his fons, who
had didinguilhed himfelf in that expedition, he left him
by his will a golden crown, weighing 20 pounds. Pifo
joined to the qualities of a good citizen the talents of a
lawyer, an orator, and hilforian.
Piso, Lams Calpurnius, a Roman conful in the
year 67 before Chrid, was author of the law which
forbade canvading for public offices, intitled I^ex CaL
purma de atnhitu. He difplayed all the firmnefs worthy
of a conful in one of the mod dormy periods of the
republic. The Roman people, deceived by the flat¬
tery of Marcus Palicanus, a turbulent and feditious fel¬
low, were on the eve of loading themfelves with the
greated difgrace, by putting the fupreme authority in¬
to ^ the hands of this man, who deferved puniffiment
rather than honours. The tribunes of the people, by
their harangues, inflamed the blind fury of the multi¬
tude, already diffidently mutinous of themfelves. In
this fituation, Pifo mounted the roflrum, and being
alked if he would declare Palicanus conful, in cafe the
fuffrages of the people ffiould concur in the nomina¬
tion, he inflantly replied, that “ he did not think the
republic was yet involved in fuch darknefs and defpair
as to be capable of committing fo infamous an a&ion.”
Being afterwards drongly and repeatedly called upon
to fay, “ what he would do, if the thing ftiould hap¬
pen his anfwer was,_“ No, I would not name him.'”
By this firm and laconic anfwer he deprived Palicanus
of the dignity to which he afpired. Pifo, according to •
Cicero, was not poffeffed of a quick conception, but
he thought maturely, and with judgment, and, by a pro¬
per firmnefs, he appeared to be an abler man than he
really was.
Piso,
P I s
Pif°. Piso, Cneius Calpurnius, was conful in the reign of
HiitumiaI~ ^uguftus> and governor of Syria under Tiberius,
: , whofe confidant he was. It is faid, that by the order
of this emperor he caufed Germanicus to be poifoned.
Being accufed of that crime, and feeing himfelf aban¬
doned by every body, he laid violent hands on himfelf
in the 20th year of our Lord. He was a man of infup-
portable pride and exceflive violence. Some inftances
of his wicked cruelty have been handed down to us.
Having given orders in the heat of his paflion to con-
duft to punifhment a foldier, as guilty of the death of
one of his companions, becaufe he had gone out of the
camp with him and returned without him, no prayers or
intreaty could prevail with Pifo to fufpend the execution
of this fentence until the affair fhould be properly in-
veftigated. The foldier was led without the entrench¬
ments, and had already prefented his head to receive
the fatal ftroke, when his companion whom he was
accufed of having killed made his appearance again.
Whereupon the centurion, whofe office it wras to fee
the fentence executed, ordered the executioner to put
up his fword into the fcabbard. Thofe two companions,
after embracing each other, are conduced to Pifo,
amidft the acclamations of the whole army, and a pro¬
digious crowd of people. Pifo, foaming with rage,
afcends his tribune, and pronounces the fame fentence
of death againft the whole three, without excepting the
centurion who had brought back the condemned fol¬
dier, in thefe terms: “ You I order to be put to death
becaufe you have been already condemned : you, be¬
caufe you have been the caufe of the condemnation
of your comrade; and you, becaufe having got orders
to put that foldier to death, you have not obeyed your
prince.”
PISSASPHALTUM, or Asphaltum, Earth-
pitch ; a fluid, opaque, mineral body, of a thick con¬
fidence, flrong fmell, readily inflammable, but leaving
a refiduum of greyifli alhes after burning. It arifes out
of the cracks of the rocks, in feveral places in the ifland
of Sumatra, and fome other places in the Eafl: Indies,
where it is much efteemed in paralytic diforders. There
is a remarkable mine of it in the ifland of Bua, {fee
Bua), of which the following curious defcription is gi¬
ven us by the Abbe Fortis. “ The ifland is divided in¬
to two promontories between the north and weft. Crof¬
ting over the top of the latter, which is not half a mile
broad, and defcending in a right line towards the fea,
one is conduced to a hole well known to the inhabi¬
tants. This hole extends not much above 12 feet, and
from its bottom above 25 feet perpendicular, arife the
P I s
marble ftrata which fuftain the irregular mafies that fur- PifTkfpKal-
round the top of the mountain. tcm
This piffafphaltum is of the moft perfeft quality, black p^[CI-a
and ffiining, very pure, odorous, and cohefive ^ and it < .. ' .
comes out almoft liquid, but hardens in large drops
when the fun fets. On breaking many of thefe drops on
the fpot, I found that almoft every one of them had an
inner cavity full of very clear water.
“ The greateft breadth of the tears that I fawr was
two inches, and the common breadth is half an inch.
The chinks and fiflures of the marble, from whence this
bituminous pitch tranfudes, are not more than the thick-
nefs of a thread; and for the moft part are fo imper¬
ceptible, that were it not for the pitch itfelf, whereby
they are blackened, they cculd not by any means be
dirtinguiffied by the naked eye. To the narrownefs of
thefe paffages is, no doubt, in part owing the fmall quan¬
tity of piffafphaltum that tranfpires.”
After fome ccnjeftures about the origin of this mine,
our author proceeds to inform us that the piffafphaltum
of Bua is correfpondent to that foffilprodudlion which by
Haffelquift, in his Travels, is called mumia miner ale, and
mumia nativa Perjiana by Kempfer, which the Egyp¬
tians made ufe of to embalm their kings (a). It is
found in a cave of Mount Caucafus, which is kept fhut,
and carefully guarded by order of the king of Perfia. One
of the qualities affigned by M. Linnaeus to the fineft bitu¬
men is to fmoke when laid on the fire, as ours does,
emitting a fmell of pitch not difagreeable. He believes
it would be very good for wounds, as the oriental mumia
is, and like the pitch of Caftro, which is frequently ufed
by the Roman chirurgeons for fraflures, contufions, and
in many external applications. See Asphaltum, Mi¬
neralogy Index.
PISSELALUM INDICUM, Barbadoes Tar; a mine¬
ral fluid of the nature of the thicker bitumens, and of all
others the moft approaching, in appearance, colour, and
confiftence, to the true piffafphaltum, but differing from
it in other refpe&s. It is very frequent in many parts
of America, where it is found trickling dowm the fides
of mountains in large quantities, and fometimes floating
on the furface of the waters. It has been greatly re¬
commended internally in coughs and other diforders of
the breaft and lungs.
PISTACIA, Turpentine-tree, Pijiachia nut and
Majlick-tree; a genus of plants belonging to the dio-
ecia clafs. The moft remarkable fpecies. are, 1. The
terebinthus, or piftachia-tree, which grows naturally in
Arabia, Perfia, and Syria, whence the nuts are annually
brought to Europe. In thofe countries it grows to the
height
[ 576 ]
(a) “ Mumiahi, or native Perfian mummy. It proceeds from a hard rock in very fmall quantity. It is a bi¬
tuminous juice, that tranfudes from the ftony fuperficies of the hill, refembling in appearance coarfe ftioema-
kers wax, as well in its colour as in its denfity and duclility. While adherent to the rock it is lefs folid, but
is formed by the -warmth of the hands. It is eafily united with oil, but repels water •, it is quite void of fmell,
and very like in fubftance to the Egyptian mummy. When laid on burning coals, it has the fmell of fulphur
tempered a little with that of naphtha, not difagreeable. There are two kinds of this mummy •, the one is va¬
luable for its fcarcity and great aiffivity. The native place of the beft mummy is far from the accefs of men, from
habitations, and from fprings of water, in the province of Daraab. It is found in a narrow cave, not above two
fathoms deep, cut like a wrell out of the mafs, at the foot of the rugged mountain Caucafus.” Kempfer. Aman.
Per/.
This defcription agrees perfeiftly with the piffafphaltum or foffil mummy of Bua, differing only in the privation
qf fn ell, which it is difficult to imagine is totally wanting in the Perfian mummy,
4
PIS [ 577 ] p 1 s.
Piftarhia. height of 2J or 30 feet: the bariv of the flem and old fcribed by way of reftoratives, eaten in {mall quantity,
   ' branches is of a dark ruflfet colour, but that of the young to people emaciated by long illnefs.
branches is of a light brown. Thefe are garnifhed with PISTIL, among botanifts, the little upright co¬
winged leaves, compofed fometimes of two, at other lumn which is generally found in the centre of every
times of three, pair of lobes, terminated by an odd one : flower. According to the Linnaean fyftem, it is the
thefe lobes approach towards an oval fliape, and their female part of generation, whofe office is to receive and
edges; are turned backward j and thefe, when bruifed, fecrete the pollen, and produce the fruit. It conlilts of
emit a fineil flmilar to that of the flrell of the nut. three parts, viz. germen, ffylus, and itigma. See Bo-
Some of thefe trees produce male and others female TANY Index.
flowers, and feme have both male and female on the PISTOIA is a city of Italy, in the duchy of Tuf-
fame tree. The male flowers come out from the fides cany, fituated on the river Stella, in a beautiful plaiu
of the branches in loofe bunches or catkins. They have near the foot of the Apennine mountains. By Pliny
no petals, but five fmall ftamina crowned by large four- it is called Piflorium, and is laid to have been once a
cornered fummits filled with farina; and when this is Roman colony. At prefent it is a bithop’s fee, fufiffra-
difeharged, the flowers fall off. The female flowers gan of Florence. The ftreeis are broad and regular,
come out in duffers from the fides of the branches : the houfes tolerably well built, but poorly inhabited
they have no petals, but a large oval germen fupport- for want of trade. Formerly it was an independent re-
ing three reflexed ftyles, and are fucceeded by oval public, but fince it was fubdued by the Florentines in
nuts! 2. The lentifeus, or common maftich tree, grows 1200, it has been in a declining condition. The ca¬
l'aturally in Portugal, Spain, and Italy. Being an thedral has a very handfome cupola, and a magnificent
evergreen, it has been preferved in this country in or- ftaircafe to afeend to it. In the chapel dedicated to St
der to adorn the green-houfes. In the countries where .Tames, where his relics are preferved, the walls are al-
it is a native, it rifes to the height of 18 or 20 feet, moft covered with plates of iilver. Plere are four mar-
covered with a grey bark on the them 5 but the bran- ble ftatues of very good workmanlhip. The marble pul-
ches, which are very numerous, are covered with a red- pit, the baflb-relievos, the veflel that holds the holy wa-
dith brown bark, and are garniffied with winged leaves, ter, and the fquare ffeeple, are the work of John Pifano.
compofed of three or four pair of fmall fpear-fliaped The Jefuits have a very fine college, and the Francif-
lobes, without an odd one at the end. 3. The orienta- cans, Dominicans, and Auguftinians, good churches,
lis, or true maftich tree of the Levant, from which the In the church of Madonna dell’ Umilta there are two
maftich is gathered, has been confounded by moft bota- ftatues, one of Leo X. and the other of Clement VII.
rical writers with the lentifeus, or common maftich tree, The public palace, fituated in a large fquare, is a hand-
above deferibed, though there are confiderable differ- fome building ; feveral of the nobility have alfo very
ences between them. The bark of the tree is brown ; good houfes. In the neighbouring mountains, called by
the leaves are compofed of two or three pair of fpear- the name of Piftora, there are many large villages, the
fliaped lobes, terminated by an odd one : the outer lobes chief of which is that of S. Marcello, belonging to the
nre the largeft ; the others gradually diminilh, the in- family of Cartoli. Thefe mountains are a part of the
nermoft being the leaft. Thefe turn of a brownifh co- Apennines, and border on the. territory of Bologna and
lour towards the autumn, when the plants are expofed the county of Vernio ; higher up is the fource of the ri-
to the open air ; but if they are under glaffes, they keep ver Renor The country about Piftoia, efpecially to-
green. The leaves continue all the year, but are not fo wards Florence, is exceeding fertile and delightful, co¬
thick as thole of the common fort, nor are the plants fo vered with all forts of fruits, corn, wine, &c. and con-
hardy. taining a vaft number of little towns, wealthy villages,
Culture. The firft fpecies is propagated by its nuts, and country feats, fo as to be reckoned the richeft and
which Ihould be planted in pots filled with light kitchen- moft beautiful in all Tufcany. It is about 20 miles N.
garden earth, and plunged into a moderate hot bed to W. of Florence, and 30 N. E. of Pifa/E. Long. 11. 29.
bring up the plants : when thefe appear, they ftiould N. Lat. 43. 55.
have a large {hare of air admitted to them, and by de- PISTOL, the fmalleft piece of fire-arms, borne at the
grees they fhould be expofed to the open air, which at faddle-bow, on the girdle, and in the pocket,
laft they will bear in all feafons, though not without PISTOLE, a gold coin, ftruck in Spain and in fe-
great danger of being deftroyed in fevere winters. The veral parts of Italy, Switzerland, &c.—The piftole has
fecond fort is commonly propagated by laying dovm the its augmentations and diminutions, which are quadruple
branches, though it may alfo be raifed from the feed in piftoles, double piftoles, and half piftoles. See MONET-
the manner already direfted for the piftachia-nut tree : Table.
and in this manner alfo may the true maftich-tree be rai- PISTON, in pump-wm-rk, is a fhort cy linder of me-
fed. But this being more tender than any of the other tal or other folid fubftance, fitted exaftly to the cavity
forts, requires to be conftantly fheltered in vfinter, and of the barrel or body of the pump. See Hydrodyna-
to have a warm fituation in fummer. Mies.
Piftachia nuts are moderately large, containing a ker- PISUM, Pease ; a genus of plants belonging to the
nel of a pale greenifh colour, covered wffth a reddifh {kin. diadelphia clafs. See Botany Index. The fpecies are
They have a pleafant, fweet, undtuous tafte, refembling 1. Thefativum, or greater garden-pea, whofe lower fti-
that of almonds; and they abound wffth a fweet and pulae are roundifh, indented, with taper foot-ftalks, and
well-tailed oil, which they yield in great abundance on many flowrers on a foot-ftalk. 2. The humile, or dwTarf
being preffed after bruifing them : they are reckoned pea, with an ereft brandling {talk, and leaves having
amongft the analeptics, and are wdiolefome and nutri- two pair of round lobes. 3. The umbellatum, rofe or
live, and are by fome efteemed very proper to be pre- crowm-pea, with four pointed acute ftimdi,-and foot-'
Vol. XVI. Part II. 4 D ftalks
PIS [ 578 ] PIS
Pi rum. {talks bearing many flowers, which terminate the flalks.
4. The maritimum, or lea-pea, with foot-ftalks which
are plain on their upper Ikie, an angular ftalk, arrow-
pointed ftipulije, and foot-ftalks bearing many flowers.
5. The Americanum, commonly called Cape-Horn pea,
with an angular trailing ftalk, w'hofe lower leaves are
fpear-ihaped, lharply indented, and thofe at the top ar¬
row-pointed. 6. The ochrus, with membranaceous
running foot-ftalks, having two leaves and one flower
upon a foot-ftalk.
There is a great variety of garden-peafe now cultiva¬
ted in Britain, which are diftinguifhed by gardeners
and feedfmen, and have their different titles; but as
great part of thefe have been feminal variations, fo if
they are not very carefully managed, by taking away
all thofe plants which have a tendency to alter before
the feeds are formed, they will degenerate into their
original ftate : therefore all thofe perfens who are cu¬
rious in the choice of their feeds, look carefully over
thofe rvhich they defign for feeds at the time when they
begin to flower, and draw out all the plants which they
diftike from the other. This is what they call roguing
their peafe; meaning hereby the taking out all the bad
plants from the good, that the farina of the former may
not impregnate. the latter} to prevent which, they al¬
ways do it before the flowers open. By thus diligently
drawing out the bad, referving thofe vdiich come ear-
lieft to flower, they have greatly improved their peafe
of late years, and are conftantly endeavouring to get
forwarder varieties \ fo that it wmuld be to little pur-
pofe in this place to attempt giving a particular account
of all the varieties now cultivated: we (hall therefore
only mention the names by which they are commonly
known, placing them according to their time of coming
to the table, or gathering for ufe.
The golden hotfpur.
The Charltqn.
The Reading hotfpur.
Mafter’s hotlpur.
Eflex hotfpur.
The dw’arf pea.
The fugar pea.
Spanifti Morotto.
Nonpareil.
Sugar dwarf.
Sickle pea.
Marrowfat.
Rofe or crown pea.
Rouncival pea.
Gray pea.
Pig pea } with fome others.
The Englilh fea-pea is found wild upon the thore in
Suffex and feveral other counties in England, and is
undoubtedly a different fpecies from the common pea.
The fifth fpecies hath a biennial root, wrhich conti¬
nues twro years. This was brought from Cape Horn by
Lord Anfon’s cook, when he paffed that cape, where
thefe peafe were a great relief to the failors. It is kept
here as a curiofity, but the peafe are not fo good for
eating as the worft fort now cultivated in Britain. It
is a low trailing plant ; the leaves have two lobes on
each foot-ftalk : thofe below are fpear-fliaped, and
lharply indented on their edges 5 but the upper leaves
are fmall, and arrow-pointed. The flowers are blue,
each foot-ftalk fuftaining four or five flowers ; the pods
are taper, near three inches long ; and the feeds are
round, about the fize of tares.
The fixth fort is annual. This growrs naturally
among the corn in Sicily and fome parts of Italy, but
is here preferved in botanic gardens for the fake of va¬
riety. It hath an angular ftalk, rifing near three feet
fcigh^ the leaves ftaud upon yonged foot-ftalks, each
uuumung IWO OCuuug JUuCB.     aJC ^ a
yellow colour, {Raped like thofe of the other fort of'
pea, but are fmall, each foot-ftalk fuftaining one
flower 5 thefe are fucceeded by#pods about two inches
long, containing five or fix roundifli feeds, which are a
little compreffed on their fides. Thefe are by feme
perlons eaten green ; but unlefs they are gathered very
young, they are coarfe, and at beft not fo good as the
common pea. It may be fown and managed in the
lame way as the garden pea.
h or an account of the method of cultivating the feve¬
ral torts of garden peafe, fo as to continue them through¬
out the feafon, fee Gardening.
The gray and other large winter peafe are feldoin
cultivated in gardens, becaufe they require a great deal
of room 5 they are therefore ufually fown in fields. For
the proper method of managing them, fee Agricul¬
ture.
In the Mufeum Rujlicum, vol. i. p. 109. we find the
following method of preparing peafe for hog-meaf„
which we fliall give in the words of the ingenious far¬
mer who communicated it.
“ 4 few }Tears aS0 (%s he)> 1 had a plentiful crop
of peafe on a ten acre piece, wEich lies near my houfe :
when they w^ere full podded and nearly ripe, I had
them hooked in the ufual manner ; but before I could
get them in, there came a heavy ftiower of rain winch
wetted them through and through j and the dull heavy
weather, with frequent fhowers which followed, pre¬
vented their drying for a confiderable time.
“ I caufed the w’ads to be from time to time turned,
to prevent the haulm from rotting; and at length a few
days funfhine dried them enough to be inned j for as
they lay hollow, the wind was greatly affiftant to the
operation.
“ Before I got them in, on examining fome of the
pods, I found that the peafe were all fprouted to a
confiderable length : this wTas what I had expected, as
I gave my crop over for loft, till after a little recol-
leftion, as the wTeather ftill continued fine, I determin¬
ed to threflr them in the field.
14 "This was accordingly done j and the corn, after
it wTas call and riddled to feparate it from the rubbifti,
was dried on my malt kiln.
“ When this operation was over, I began to reflect
in what manner I Ihould difpofe of my peafe, beino-
fenfible that they could not be proper for feed, and
Handing no chance of difpofing of them to any advan¬
tage in the market.
“ At length, as it was then a time of w^ar, and of
courfe there was a great demand for pork for the ufe
of the navy, I determined to buy a confiderable num¬
ber of lean hogs, that I might by their means confume
this crop on my own premifes, and in that manner make
the moft of it.
“ My expe&ations were more than anfwered ; for I
found, by repeated experience, that three bufhels of
the peafe I have mentioned w7ent nearly as far in fat¬
tening the hogs I bought as four bufhels got in dry
and hard in the manner ufually praffifed.
“ This difeovery I made feveral years ago, and it
has turned out to my advantage 5 for fince that time
I have been quite indifferent as to the weather in
which my peafe are hooked, being rather better pleaf-
ed, as far as relates to them, with wet than dry wea¬
ther)
P I T
Fifiim tli£r j but if tbe weather happens to be
Pitcairne t’me are r*Pe’ ^ a^ways caufe as many as I want
i t - for feeding my hogs, which are not a few in a year,
to be regularly malted in the fame manner nearly as
my barley : this management has of late fucceeded
very well with me, and I therefore intend to conti¬
nue it.
“ Befides feeding my hogs with thefe malted peafe,
I have often given them to my horfes, with which they
agree very well, and are heartening food.
“ Turkeys will fatten apace on them alfo, and be
fine meat.
“ I have applied my malted peafe to many other
ufes, which I have not at prefent time to enumerate :
but were they only ufed for feeding hogs and horfes,
it is ftill worth while to prepare fome in this manner
every year.”
PIT coal, or Stone coal. See Coal, Minera¬
logy Index, and Coalery.
The coal-trade is of infinite importance to Great Bri¬
tain, which never could have arrived at its prefent com¬
mercial eminence without it; and this eminence it wTill
be impoffible to retain if coal (hould ever become fcarce.
This we truft is not likely to be the cafe, though Mr
Williams exprefles great fears for it, and informs us that
at Newcaftle and in many parts of Scotland, the mines
near the fea are already w^afted, the firft confequence of
which muft be an enormous rife in the price. See
his obfervations on this fubjefl in his Natural Hijlory
of the Mineral Kingdom. This author fays, that coal
was not difcovered till between the middle of the 12th
and beginning of the 13th centuries : it is therefore, ac¬
cording to him, 400 years fince it wms firft difcovered
in Britain, but they have not been in common ule for
more than 200 years. The fame author makes many
excellent obfervations on the appearances and indications
of coal, inftru£lions about fearching for it, remarks on
falfe and doubtful fymptoms of coal ; for all which, to¬
gether wfith his obfervations on the different kinds of
Scots coal, wt lhall refer our readers to the work itfelf j
the firft part of which, occupying a large proportion of
rt, is upon the Jlrata of coal, and on the concomitant
frata. See Geology and Strata of the earth.
PIT AH AY A Call us Pitajaya. Lin. Syft. Vegeta-
bilium. Jacquin Amer. 151. ed. 2d. p. 75. M. E. Car-
thagena), a ftirub peculiar to California, the fruit of
which forms the greateft part of the harveft of the na¬
tives. Its branches are finely fluted, and rife vertical¬
ly from the ftem, fo as to form a very beautiful top.
The fruit is like a horfe-chefnut $ in fome wdiite, in
others yellow7, and in others red, but always exquifitely
delicious, being a rich fiveet, tempered with a grateful
acid. See Cactus, Botany Index.
PITCAIRNE, Dr Archibald, an eminent phyfi-
cian and ingenious poet, was defcended from the ancient
lamily of tbe Pitcairnes of Pitcaime in Fifefliire, and
was born at Edinburgh on the 25th of December 1652.
He commenced his ftudies at the fchool of Dalkeith j
and from thence he was removed to the univerfity of
Edinburgh, where he improved himfelf in claflical learn¬
ing, and completed a regular courfe of philofophy. His
friends, according to the authors of the Biografihia Bri-
tannica, were defirous that he fhould follow the profef-
fion of theology. The unpleafant gloom, however,
[ 579.3 PIT
dry jit the which at that time hung over religion and its profefiors Pitcairr,e.
in Scotland, could not but very ill fuit with that native'
cheerfulnefs of temper and liberality of mind wdiich
made him, long after, a mark for the arrows of precife-
nefs and grimace. The lawr feems to have been his own
choice, and to this fcience he turned his attention. With
an ardour peculiar to himfelf, and an ambition to excel
in whatever he undertook, he purfued it with fo much
intenfenefs, that his health began to be impaired. On
this account, his phyficians advifed him to fet out for the
fouth of France. By the time he reached Paris, he was
happily fo far recovered, that he determined to renew
his ftudies; but being informed that there was no able
profeffor of law in that city, and finding feveral gen¬
tlemen of his acquaintance engaged in the ftudy of
phyfic, he W’ent with them to the leftures and hofpi-
tals, and employed himfelf in this manner for feveral
months till his affairs called him home.
On his return, he applied himfelf chiefly to the ma¬
thematics. It is not ufual to fee the briars of this
fcience and the flow’ers of poetry growing in the fame
foil. Here, however, they were happily united; and
to this union perhaps was owing that Angular command
°f judgement, over one of the livelieft of fancies, which
appears in every part of his works. His intimacy with
Dr David Gregory, the celebrated mathematical profef¬
for, began about the fame time ; and probably conduced
to cherifh his natural aptitude for this ftudy. It was
then in a great meafure, new to him ; it foon became
his principal delight 5 his progrefs in it was rapid, and
correfpondent to his progrefs in other purfuits. His im¬
provements on the method of infinite feries then adopt¬
ed, which Dr Wallis of Oxford afterwards publiihed,
were a confpicuous and early proof of his abilities in this
fcience.
Had Dr Pitcairne continued to profecute the ftudy of
the law, and could he have moulded his principles to
the times, the firft offices and honours of the ftate might
have been looked for without prefumption as the pro¬
bable reward of fuch talents as he poffeffed. Struck,
however with the charms of mathematical truth which
had been lately introduced into the philofophy of medi¬
cine, and hoping to reduce the healing art to geometri¬
cal method, he unalterably determined on this lefs af-
piring profeflion. At the penod when he formed this
refolution, the ideas of the medical world, already fuf-
ficiently confufed, wrere ftill farther jumbled by the dif-
covery of the circulation of the blood, which had as yet
produced nothing but doubt, uncertainty, and aftonifh-
ment. In Edinburgh at that time there was no fchool,
no hofpital, no opportunity of improvement but the
chamber and the fhop. He therefore foon after re¬
turned to Paris. Genius and induftry are unhappily,
not often united in the fame character : of fuch an
union, however, Dr Pitcairne is a celebrated inftance.
During his refidence in France, he cultivated the object
of his purfuit with his natural enthufiafm, and with a
fteadinefs from which he could not be diverted by the
allurements of that joy which, in his hours of focial and
feftive intercourfe, he alwavs felt and always gave.
Among his various occupations, the ftudy of the ancient
phyficians feems to have had a principal (hare. This
appears from a treatife which he publifhed fome time
after his return j and it ftiows, that he wifely determined
4 D 2 to
Pitcaime.
PIT [ 580 ] P
to know the progrefs of medicine from its earlieft pe- foplorum feBa & liheram.
nods, before he attempted to reform and improve that
fcience.
I T
In this he clears medicine Pitcaime.
On the 13th of Auguft 1680, he received, from the
faculty ©i Kheims the degree of Dodtor j which, on
the 7 th of Auguft 1699, was iikewife conferred on him
by the univerfiiy of Aberdeen 5 both being attended with
marks of peculiar diftinftion. Other medical honours
are faid to have been conferred on him in France and
elfewhere; but nothing affords a more unequivocal tefti-
mony to his abilities than that which the furgeons of
Edinburgh gave, in admitting him, freely and unfolicit-
ed, a member of their college. None had fucli opportu-
nities of judging of his merit as a pradlidoner, and on
no phyfician did they ever beftow the fame public mark
of refpedt. Soon after his graduation at Rheims, he re¬
turned to Edinburgh j where, on the 29th of November
1681, the Royal College of Phylicians was initi'uted •,
and his name, among others, graced the original patent
from the crown.
In h;s Solatia Problematis de Inventorilus, the treatife
above alluded to, he difcovers a wonderful degree of
medical literature, and makes ufe of it in a manner that
does great honour both to his head and his heart. His
objeft is to vindicate Dr Harvey’s claim to the difco-
very of the circulation of the blood. The difcovery
was, at firft. controverted by envy, and reprobated by
ignorance. When at length its truth was fully efta-
blilhed, many invidioufly attempted to tear the laurels
from the illuftrious Engliftrman, and to plant them on
the brows of Hippocrates and others. Had the attempt
been direfted againft himfelf, the generous foul of Pit-
cairne could not have exerted more zeal in a defence j
and his arguments remain unanfwered.
During his refidence in Scotland, his reputation be¬
came fo confiderable, that, in the year 1691, the uftiver-
fity of Leyden folicited him to fill the medical chair, at
that time vacant. Such an honourable teftimony of
refpect, from a foreign nation, and from fuch an univer-
fity, cannot perhaps be produced in the medical biogra¬
phy of Great Britain. The luftre of fuch characters re¬
flects honour on their profeflion, and on the country
which has the good fortune of giving them birth ; and
ferves to give the individuals of that country not only
a ufeful eftimation in their own eyes, but in thofe alfo
of the reft of the wmrld. Dr Pitcairne’s well-known
political principles excluded him from public honours
and promotion at home : he therefore accepted the invi¬
tation from abroad j and, on the 26th of April 1692,
delivered, at Leyden, his elegant and mafterly inaugural
oration : Oratio qua ojlenditur medicinam ab omniphilo-
from the rubbiih of the old philofophyj feparates it from
the influence of the different fedts 5 places it on the
broad and only lure foundation of experience} fhows how
little good inquiries into the manner how medicines ope¬
rate have done to the art j and demonfirates the necef-
fily of a fedulous attention to their efl'efts, and to the va¬
rious appearances of diieale.
Nothing (fays an elegant panegyrift * of our author) * Dr Chas.
marks a lupenority of intellect io much as the cou- Webiter, in
rage rcquifite to item a torrent of obftinately prevailingthe.Har-
and groundless opinions. For this the genius and
lents of Pitcairne were admirably adapted 5 and, in hisdmburgh"
oration, he difplays them to the utmoft. It was receivedftie year
with the higheft commendations j and the adminiftrators, l7Sl; from
to tcftify their feme of fuch an acquifition to their uni- wmch per‘
p. , , . g . ronnance
verlity, greatly augmented the ordinary appointment ofthe pretent
his chair. article is
He dilcharged the duties of his office at Leyden f0;cliiefly ex-
as to anlwer the moft fanguine expectations. jqe tia<ited.
taught with a perfpicuity and eloquence which met
with univerfal applaule. Independently of the enco¬
miums of Boerhaave and Mead, who were his pupils,
the numerous manufeript copies of his leCiures, and
the mutilated fpecimen of them f which found its way f Element a.
into the world without his knowledge, fhow howr jult- Medicinx,
ly it was beftowed. At the fame time, he was not
more celebrated as a profeffor than as a practical phy¬
fician ; and notwithftanding the multiplicity of his
bufinefs in both thefe characters, he found leifure to
publifti feveral treatifes on the circulation, and fome
other of the moft important parts of the animal econo-
my (a).
_At the elefe of the feflion he fet out for Scotland,
with an intention of returning in time for the fucceed-
ing one. On his marrying (b) the daughter of Sir Ar¬
chibald Stevenfon, the objeCt of his journey, her rela¬
tions would on no account confent to part with him
again. He was therefore reluctantly obliged to remain ;
and he wrote the univerfity a polite apology, which was
received with the ulmoft regret. Fie even declined the
moft flattering folicitations and tempting offers to fettle
in London. Indeed he foon came into that extenfive
praftice to which his abilities entitled him, and was alfo
appointed titular profeffor of medicine in the univerfity
of Edinburgh.
The uniformity of a profeflional life is feldom inter¬
rupted by incidents worthy of record. Specimens, how¬
ever, of that brilliant wit with which he delighted his
friends in the hours of his leifure, continue to entertain
us (c) : and the effeCts of that eminent fkill which he
excited.
(a) Dr Boerhaave gives the following charaCler of thefe and fome other of Dr Pitcairne’s differtations, which
were colleCled and publifhed at Rotterdam, anno 1701 : “ Haec feripta optima lunt et perfecta, five legas Differta-
tionem de Motu Sanguinis per Pulmones, five alia opufcula, five ultimum traefatum de Opio.” MethadusJludii, ab
Hallero edit a, p. 569.
(b) He had been married before to a daughter of Colonel James Hay of Pitfour, by whom he had a fon and-
daughter, who both died young.
(g) Vide Pitcarmi Poemata.—Several of his poems, however, are obfeure, and fome of them totally unintel¬
ligible without a key. In thofe of them which are of a political kind, he wfilhed not to exorefs himfelf too
clearly; and in others, he alludes to private occurrences wftfich were not knowm beyond the circle of his com¬
panions. His poem (Ad Lindefium), addreffed to his friend Lindfey, is commented on by the authors of the Bio-
graphia Bntannica ; and it is to be regretted that it is the only one on which they have been folicitous to throw
light.
PIT [ 5S
prtcaime. exerted in tKe cure of difeafe, ftill operate to the good
0f pofterity.
The difeovery of the circulation, while in fome mea-
fure it exploded the chemical and Galenical doctrines,
tended to introduce mathematical and mechanical rea-
foning in their Head. Of this theory (d) Dr Pitcairne
was the principal fupport, and the firft who introduced
it into Britain. A mathematical turn of mind, and a
with for mathematical certainty in medicine, biaffed him
in its favour, and he pufhed it to its utmolt extent. One
is at a lofs whether mod to admire or regret fuch a
wafte of talents in propping a theory which, though
fubverfive of former ones, was to fall before others but
a little more latisfaftory than itfelf. Mechanical phy-
ficians expected more from geometry than that fcience
could grant. They made it the foundation inftead of
an auxiliary to their inquiries, and applied it to parts of
nature not admitting mathematical calculations. By
paying more attention afterwards to the fupreme influ¬
ence of the living principle, the fource of all the mo¬
tions and functions of the body, it was found that thefe
could not be explained by any laws of chemiftry or me-
chanifm. They are fall, however, involved in obfeuri-
ty ; and notwithftanding the numberlefs improvements
which have taken place in the fciences connedfed with
medicine, will perhaps remain infcrutable while man
continues in his prefent ftage of exiftence.
i ] . PIT
In a fcience fo flowly progreffive as that of medi- Pitcairne.
cine, Dr Pitcaime did a great deal. By labouring in “"""v *
vain for truth in one road, he laved many the fame
drudgery, and thereby fhowed the neeeffity of ano¬
ther. He not only exploded many falfe notions of
the chemifts and Galenills which prevailed in his time,
but many of thofe too of his own feet. In particu¬
lar, he Ihowed the abfurdity of referring all difeafes
and their cures to an alkali or an acid (e). He refuted
the idea of fecretion being performed by pores diffe¬
rently fhaped (f), Bellini’s ©pinion of effervefcences in
the animal fpirits with the blood, and Borelli’s of air
entering the blood by refpiration (g). He proved the
continuity of the arteries and veins (h) ; and feems tu
have been the firft who Ihowed that the blood flows
from a fmaller capacity into a larger; that the aorta,
with refpecl to the arterial fyftem, is the apex of a
cone (i). In this therefore he may be confidered as
the latent fpring of the difeoveries refpe'dfing the powers
moving the blood. He introduced a fimplicity of pre-
feription unknown in pharmacy before his time (k) :
and fuch was the ftate of medicine in this country, that
fcarcely have the works of any cotemporary or preced¬
ing author been thought worthy even of prefervation(L).
As to the errors of his philofophy, let it be remember¬
ed, that no theory has as yet flood the teft of many
years in an enlightened period. His own hung very
loofely
light. “ Some parts (fay they) of this poem, are hardly intelligible, without knowing a circumftance in the doc¬
tor’s life, which he often told, and never without fome emotion. It is a well known rtory of the two Platonic phi-
lofophers, who promifed one another, that whichever died firft fhould make a vifit to his furviving companion, ihis
ftory being read by Mr Lindfey and our author together, they being both then very young, entered into the fame
engagement. Soon after, Pitcairne, at his father’s houfe in Fife, dreamed one morning that Lindfey, xvho was then
at Paris, came to him, and told him he wTas not dead, as was commonly reported, but ftill alive, and lived in a very
agreeable place, to which he could not yet carry him. By the courfe of the poft news came of Lindfey’s death,
which happened very fuddenly the morning of the dream. When this is known, the poem is eafily underftood. and
Thmes with no common degree of beauty.
“ Lyndefi ! Stygias jamdudum ve£te per undas,
“ Stagnaque Cocyti non adeunda mihi ;
“ Excute paulifper Lethaei vincula fomni,
“ Ut feriant animum carmina noftra tuum.
w Te nobis, te redde tuis, promiffa daturas
“ Gaudia ; fed proavo fis comitante redux :
“ Namque novos viros rnutataque regna videbis,
‘ Paffaque Teutonicas feeptra Britanna manus *. * Written
“ He then proceeds to exclaim againft the principles and pra&ices which produced this Teutonic violence ^
upon the Britifti feeptre; and concludes with a wifh, that Lindfey might bring Rhadamanthus with him to pu-
nifli them.
“ Unus abeft fcelerum vindex Rhadamanthus j amice,
“ Dii faciant reditus fit comes ille tui.
“ Everyone fees how much keener an edge is given to the fatire upon the Revolution, by making it an addition¬
al reafon for his friend’s keeping his promife to return him a vifit after his death.”
(d) See the article Physiology.
(e) Pitcarnii Dijfertationes, Edin. edit. 1713. De opera quam pneftant corpora acida vel alkalica in curatione-
morborum.
(f) De circulatione fanguinis per vafa minima.
(g) De diverfa mole qua fanguis fluit per pulmones.
(h) De circulatione fanguinis per vafa minima.
(1) De circulatione fanguinis in animalibus genitis et non genitis.
(k) E/ementa Medicince, lib. i. cap. 21. et paflim.
(l) The firft medical publication which diftinguifhed this country, after Dr Pitcairne’s, was that of the Edin¬
burgh Medical Effays, in the year 1732. Vid, the article Monro.
FIT [ 582 ]
Fitcairne l00fely about liim (m) j and the prefent generally re- the wind
Pitch/no-. C£ive^ pra&ice differs from his very little in reality.
 r—,‘ - He treated inflammatory and hemorrhagic difeafes by
bleeding, purging, and bliftering, as has been done uni¬
formly and folely on the different theories fince. His
method of adminiflering mercury and the bark is ob-
ferved at this day; and with refpeft to febrile, ner¬
vous, glandular, and dropfical affe&ions, they feem to
be as often the opprobriums of the art now as they were
then.
Dr Pitcairne was univerfally confidered as the firft
phyfician of his time. No one appears ever to have
had fo much praftice in this country, or fo many con-
fultations from abroad4, and no one, from all accounts,
ever pra&ifed with greater fagacity and fuccefs. The
higheft thought themfelves honoured by his acquaint¬
ance, and the lowed were never denied his affiftance
and advice. The emoluments of his profeffion muff
have been great; but his charities are known to have
been correfpondent. The poffefllon of money he poft-
poned to more liberal objefts ; he colle&ed one of the
fineft private libraries in the world ; which was pur-
chafed, after his death, by the Czar of Mufcovy. Not-
withftanding the fatigues he underwent in the exercife
of his profeffion, his conftitution was naturally deli¬
cate. About the beginning of Oftober 1713, he be¬
came affefted with his laft illnefs ; and on the 23d he
died, regretted by fcience as its ornament, by his "coun¬
try as its boaft, and by humanity as its friend. He
left a fon and four daughters : of whom only one of the
latter now furvives. The prefent noble family of Kelly
are his grandchildren.
Some anonymous publications are attributed to Dr
Pitcairne, particularly a treatife De Legibus Hijlorice
Naturaiis, &c.; but the only ones he thought proper
to legitimate are his Dijfertationes Medico;, and a Ihort
effay De Salute.
PITCAITHLY. See Pitkeathly.
PITCH, a tenacious oily fubftance, drawn chiefly
from pines and firs, and ufed in (hipping, medicine, and
various arts : or it is more properly tar infpiffated by
boiling it over a flow fire. See Tar.
FoJJil Pitch. See Petroleum, Mineralogy In¬
dex.
PITCHING, in fea-affarrs, may be defined the ver¬
tical vibration which the length of a fliip makes about
her centre of gravity; or the movement by which fhe
plunges her head and after-part alternately into the hol¬
low of the fea. This motion may proceed from two
caufes: the waves which agitate the veffel; and the
wind upon the fails, which makes her ftoop to every
blaft thereof. The firft abfolutely depends upon the
agitation of the fea, and is not fufceptible of inquiry ;
and the fecond is occafioned by the inclination of the
mails, and may be fubmitted to certain eftablifhed
maxims.
When the wind a£fs upon the fails, the mail yields to
its effort, with an inclination which increafes in propor¬
tion to the length of the maft, to the augmentation of
P I T
and to the comparative weight and diftrlbu- Pitching
tion of the (hip’s lading. jj
1 he repullkui oi the water, to the effort of gravity,
oppofes itfelf to this inclination, or at lead fultains it,
by as much as the repulfion exceeds the momentum,
or abfolute effort of the maft, upon which the wind
operates. At the end of each blaft, when the wind
fufpends its adlion, this repulfion lifts the veffel; and
thefe fucceflive inclinations and repulfions produce the
movement of pitching, which is very inconvenient;
and, when it is confiderable, will greatly retard the
courfe, as well as endanger the maft, and (train the vef¬
fel.
_ PITH, in vegetation, the foft fpongy fubftance con¬
tained in the central parts of plants and trees*. * See Plant*
PITHO, in fabulous hiftory, the goddefs of per-
fuafion among the Romans. She was fuppofed to be
the daughter of Mercury and Venus, and was reprefent-
ed with a diadem on her head, to intimate her influence
over the. hearts of man. One of her arms appeared
raifed as in the attitude of on orator haranguing in a
public affembly ; and with the other (lie holds a thun¬
derbolt and fetters, made with flowers, to fignify the
powers of reafoning and the attraftions of eloquence.
A caduceus, as a (ymbol of perfuafion, appears at her
feet, with the writings of Demofthenes and Cicero, the
two mod celebrated among the ancients, who under-
ftood how to command the attention of their audience,
and to roufe and animate their various paflions.—A Ro¬
man courtezan. She received this name on account of
the allurements which her charms poffeffed, and of her
winning expreflions.
PITHOM, one of the cities that the children of
Ifrael built for Pharaoh in Egypt (Exod. i. 11.) du¬
ring the time of their fervitude. This is probably the
fame city with Pathumos mentioned by Herodotus,
which he places upon the canal made by the kings Ne-
cho and Darius to join the Red fea with the Nile, and
by that means with the Mediterranean. We find alfo
in the ancient geographers, that there was an arm of
the Nile called Pathmeticus, P/iatmicus, Phatnicus, or
Phatniticus. Bochart fays, that Pithom and Raamfes
are about five leagues above the divifion of the Nile,
and beyond this river ; but this affertion has no proof
from antiquity. This author contents himfelf with re¬
lating what was faid of Egypt in his own time. Mar-
(ham vvill have Pithom to be the fame as Pelufium or
Damietta.
PITHOU or PlTHOEUS, Peter, a Frenchman of
great literary eminence, was defcended from an ancient
and noble family in Normandy, and born at Troyes in
1539. His tafte for literature appeared very early, and
his father cultivated it to the utmoft. He firft ftudied
at Troyes, and was afterwards fent to Paris, where he
became firrt the fcholar, and then the friend, of Tur-
nebus. Having finilhed his purfuits in languages and
the belles lettres, he was removed to Bourges, and
placed under Cujacius in order to ftudy civil law. His
father was well (killed in this profeffion, and has left no
inconfiderable
(m) Patet (fays hemedicinam effe memoriam eorum quae cuilibet morbo ufus oftendit fuiffe utilia. N^m notas
non effe corporum intra venas fluentium aut confiftentium naturas, adeoque fola obfervatione innotefcere quid cuique
morbo conveniat poftquam faepius eadem eidem morbo profuiffe comperimus. De Div. Morb.
4
pit r 583 ] pit
Pithoii, inconuderable fpecimen of his judgement in the advice
j^itifcus. ^ ]le gaye pon wjt^ regarj to aCqUiriI1g a knowledge
* of it j which was, not to fpend his time and pains upon
voluminous and barren commentators, but to confine
his reading chiefly to original writers. He made fo
rapid a progrefs, that at feventeen he was able to fpeak
extempore upon the mod difficult queftions j and his
mafter was not afhamed to own, that even himfelf had
learned fome things of him. Cujacius afterwards re¬
moved to Valence j and Pithoeus followed him, and con¬
tinued to profit by his ledhires till the year 1560. He
then returned to Paris, and frequented the bar of the
parliament there, in order to join praftical forms and
ufages to his theoretic knowledge.
In 1563, being then 24, he publiffied Adverfaria
Subfeciva, a work highly applauded by Turnebus, Lip-
lius, and other learned men j and which laid the foun¬
dation of that great and extenfive fame he aftemards
acquired. Soon after this, Henry III. advanced him
to fome confiderable polls ; in which, as well as at the
bar, he acquitted himfelf moll honourably. Pithoeus
being a Protellant, it was next to a miracle that he
was not involved in the terrible maffacre of St Bartho¬
lomew in 1572 ; for he was at Paris where it was com¬
mitted, and in the fame lodgings with feveral Hugue¬
nots, who were all killed. It feems indeed to have
frightened him out of his religion 5 which having, ac¬
cording to the cullom of converts, examined and found
to be erroneous, he foon abjured, and openly embraced
the Catholic faith. He afterwards attended the duke
of Montmorency into England; and on his return,
from his great wifdom, good nature, and amiable man¬
ners, he became a kind of oracle to his countrymen,
and even to foreigners, who confulted him on all im¬
portant occafions 5 and inllance of which we have in
Ferdinand the grand duke of Tufcany, who not only
confulted him, but even fubmitted to his determination
in a point contrary to his interells. Henry III. and IV.
were greatly obliged to him for combating the League
in the moll intrepid manner, and for many other fervices,
in which he had recourfe to his pen as well as to other
means.
Pithoeus died upon his birth-day In 1596, leaving
behind him a wife whom he had married in 1 ^79, and
fome children. Thuanus fays he was the moll excellent
and accomplilhed man of the age in which he lived $
and all the learned have agreed to fpeak well of him.
He collefled a very valuable library, containing a va¬
riety of rare manufcripts, as well as printed books j
and he took many precautions to hinder its being dif-
perfed after his death, but in vain. He publilhed a
great number of works upon law, hillory, and claffical
literature ; and he gave feveral new and corredl edi¬
tions of ancient writers. He was the firll who made
the world acquainted with the Fables of Phiedrus;
which, together with the name of their author, were ut¬
terly unknown and unheard of, till publilhed from a ma-
nufcript of his.
PITISCUS, Samuel, a learned antiquary, was bom
at Zutphen, and was re£lor of the college of that city
and afterwards of St Jerome at Utrecht, where he died
on the firll of February 1717, aged 90. He wrote,
1. Lexicon Antiquilatum Romanarutn, in two volumes
folio; a work which is elleemed. 2. Editions of many
Latin authors, with notes y and other works.
PITKEATHLY, or PlTCAITHLY, is the name of Pitkeatldy,
an ellate in Strathern in Scotland, famous for its mine-, Pltot’
ral waters. An intelligent traveller * gives the follow- % ^
ing account of it. “ The fituation of the mineral journey
fpring at Pitcaithly, the efficacy with which its waters the
are laid to operate in the cure of the difeafes for which Wejlern
they are ufed, and the accommodations which the neigh- c°un^es °j
bourhood affords, are all of a nature to invite equal-^
ly the lick and the healthy. Two or three houfes are
kept in the Ityle of hotels for the reception of Hr angers.
There is no long-room at the well} but there are plea-
ling w'alks through the adjoining fields. Good roads
afford eafy accefs to all the circumjacent country. This
delightful tra£t of Low'er Strathern is filled with houfes
and gardens, and ftations from wffiich wdde and delight-
fill profpedls may be enjoyed 5 all of which offer agree¬
able points to wfliich the company at the wrell may di-
re<ft their forenoon excurfions; converfation, mufic,
dances, wffiift, and that bell friend to elegant, lively,
and focial converfe, the tea-table, are fuffident to pre¬
vent the afternoons from becoming languid : and in the
evenings nothing can be fo delightful as a walk when
the fetting fun fheds a foft llanting light, and the dew
has juft not begun to moiften the grafs.—Thus is Pil-
caithly truly a rural watering-place. The company
cannot be at any one time more in number than two or
three families. The amufements of the place are limply
fuch as a fingle family might enjoy in an agreeable fitu¬
ation in the country •, only the fociety is more diverfifi-
ed by the continual change and fludluation of the com¬
pany.” Ihe w’aters of this place are of a fulphureous -
nature.
PITOT, Henry, of a noble family in Languedoc,
was born at Aramont in the diocefe of Ufez, on the
29th of May 1695, and died there on the 27th of De¬
cember 1771, aged 76. He learned the mathematics
without a mailer, and went to Paris in 1718, where he
formed a clofe friendlhip with the illuftrious Reaumur.
In 1724, he wras admitted a member of the Royal Aca¬
demy of Sciences at Paris, and in a few years rofe to
the degree of a penfioner. Befides a vail number of
Memoirs printed in the colledlion of that fociety, he
publilhed in 1731 the Theory of the Working of Ships,,
in one volume 410 ; a wmrk of confiderable merit, which
was tranllated into Englilh, and made the author be ad¬
mitted into the Royal Society of London. In 1740,
the ftates-general of Languedoc made choice of him for
their chief engineer, and gave him at the fame time the
appointment of inlpeftor general of the canal which
unites the two feas. That province is indebted to him
for feveral monuments of his genius, which will tranf-
mit his name wnth luflre to pofterity. The city of
Montpellier being in want of water, Pitot brought from
the dillance of three leagues the water of two fprings
which furnilh a plentiful fupply of that neceffary article.
They are brought to the magnificent Place du Peyron,
and thence are diftributed through the city. This afto-
nilhing work is the admiration of all ftrangers. The il¬
luftrious marlhal de Saxe was the great patron and friend
of Pitot, who had taught this hero the mathematics. In
1754 he was honoured with the order of St Michael.
In 17^5 he had married Maria Leonina Pharambier de
Sabballoua, defcended of a very ancient noble family of
Navarre. By this marriage he had only one fon, who
was firft advocate-general of the court of accounts,
Pitot
II
Pitt.
pit r 584
aids, and finances of Montpellier. Pitot was a pradfical
philofopher, and a man of uncommon probity and can-
dour. He was alfo a member of the Hoyal Society of
Sciences of Montpellier 5 and his eulogium was pro¬
nounced in 1772 by M. de Rdtte perpetual fecretary, in
prefence of the dates of Languedoc ; as it like wife was
at the Royal Academy of Sciences of Paris by Abbe de
Fouchi, who was then fecretary.
PITS, John, the biographer, was born in 1560, at
Aulton in Hampfhire, and educated at Wykeham’s
fchool, near Winchefter, till he was about 18 years of
age j when he was fent to New-college in Oxford, and
admitted probationer fellow. Having continued in that
univerfity not quite two years, he left the kingdom as a
voluntary Romilh exile, and retired to Douay ; thence
he went to the Englifli college at Rheims, where he re¬
mained about a year j and then proceeded to Rome,,
where he continued a member of the Englifh college
near feven years, and was made a prieft. "in 1589 he
returned to Rheims ; and there, during two years,
taught rhetoric and the Greek language. He now
quitted Rheims on account of thetivil war in France j
and retired to Pont a Moufibn in Lorrain, where he
took the degrees of mailer of arts and bachelor in divi¬
nity. Hence he travelled into Germany, and refided a
year and a half at Triers, where he commenced licen¬
tiate in his faculty. From Triers he vifited feveral of
the principal cities in Germany j and continuing three
years at Ingoldftadt in Bavaria, took the degree of doc¬
tor in divinity. Thence having made the tour of Italy,
he returned once more to Lorrain ; where he was pa-
tronifed by the cardinal of that duchy, who preferred
him to a canonry of Verdun ; and about two years after
he became confeflbr to the duchefs of Cleves, daughter
to the duke of Lorrain. During the leifure he enjoyed
in this employment, he wrote in Latin the lives of "the
kings, bilhops, apodolical men, and writers of Eng¬
land. The lalt of thefe, commonly known and quoted
by this title, De illuflrihus Anglia; fcriptoribus, was
publilhed after his death. The three fird remain dill
m manufcript among the archives of the collegiate
church of Liverdun. rJ he duke of Cleves dying after
Pits had been about twelve years confeffor to the duch¬
efs, die returned to Lorrain, attended by our author,
who was promoted to the deanery of Liverdun, which,
with a canonry and officialddp, he enjoyed to the end
cflds life. He died in 1616, and was buried in the
collegiate church. Pits was undoubtedly a fcholar,
and not an inelegant writer ; but he is judly accufed
of ingratitude to Bale, from whom he borrowed his
materials, without acknowledgment. He quotes Le-
land with great familiarity, without ever having feen
his book: his errors are innumerable, and his par¬
tiality to the Romidi writers mod obvious •, neverthe-
lefs we are obliged to him for his account of feveral po-
pidi authors, who lived abroad at the beginning of the
Reformation.
PITT, Christopher, an eminent Englidi poet,
celebrated for his excellent tranflation of Virgil’s iEneid,
was born in the year 1699. Having dudied four years
at New-college, Oxford, he was prefented to the living
of Pimperne in Dorfetfhire, which he held during the
remainder of his life. He had fo poetical a turn, that
while he was a fchool-boy he wrote two large folios
of manufcript poems, one of which contained an en-
1 PIT
tire tranflation of Lucan. He was much efteemed
while at the univerfity j particularly by the celebrated '
Dr Young, who ufed familiarly to call him his fon.
Next to his fine tranllation of Virgil, Mr Pitt gained
the greateft reputation by his excellent Englifli tranlia-
tion of Vida’s Art of Poetry. This amiable poet died in
the year 1748, without leaving, it is faid, one enemy
behind him.
Pitt, William, earl of Chatham, a mod celebrated
Britifh datefman and patriot, was born in November
1708. He was the younged fon of Robert Pitt, Efqj
of Boconnock in Cornwall; and grandfon of Thomas
Pitt, Efqj governor of Fort St George in the Ead In¬
dies, in the reign of Queen Anne, who fold an extraordi¬
nary diamond to the king of France for 135,000!. and
thus obtained the name of Diamond Pitt. Flis intel-
lecdual faculties and powers of elocution very foon made
a didirrguiflied appearance j but at the age of 16 he
felt the attacks of an hereditary and incurable gout, by
.which he w’as tormented at times during the red of his
life.
His lordfliip entered early into the army, and ferved
in a regiment of dragoons. Through the interefl of
the duchefs of Marlborough he obtained a feat in
parliament before he w as 21 years of age. Flis firft
appearance in the houfe was as reprefentative of the
borough of Old Sarum, in the ninth parliament of
Great Britain. In the 10th he reprefented Seaford,
Aid borough in the 11 th, and the city of Bath in the
1 2th 5 wdiere he continued till he was called up to the
houfe of peers in 1766. The intention of the duchefs
in bringing him thus early into parliament was to op-
pofe Sir Robert Walpole, whom he kept in awe by the
force of his eloquence. At her death the duchefs left
him 10,00c 1. on condition, as was then reported, that
he never fhould receive a place in adminiftration. How¬
ever, if any fuch condition was made, it certainly was
not kept on his lordfhip’s part. In 1746 he was ap¬
pointed vice-treafurer of Ireland, and foon after pav-
mafler general of the forces, and fworn a privy-counfel-
lor. He difcharged the office of paymafter with fuch
honour and inflexible integrity, refufing even many of
the perquifites of his office, that his bittereft enemies
could lay nothing to his charge, and he foon became
the darling of the people. In 17 5:5 he refigned the of¬
fice of paymafter, on feeing Mr Fox preferred to him.
The people were alarmed at this refignation j and be-
ing difgufted with the unfuccefsful beginning of the war,
complained fo loudly, that, on the 4th December 1 7 ;6,
Mr Pitt was appointed fecretary of ftate in the room of
Mr Fox afterwards Lord Holland ; and other promo¬
tions wrere made in order to fecond his plans. He then
took fuch meafures as were neceffary for the honour and
interefl of the nation j but in the month of February
I757> having refufed to aflent to the carrying on a war
in Germany for the fake of his majefty’s dominions on
the continent, he was deprived of the feals on the 5th of
April following. Upon this the complaints of the peo¬
ple again became fo violent, that on the 29th of June
he wTas again appointed fecretary, ai\d his friends filled
other important offices. The luccefs with which the
war was now conducted is univerfally known j yet on
the 5th of Odlober 1761, Mr Pitt, to the aftonifhment
of almoft the whole kingdom, refigned the feals into his
majefty’s own hands. The reafon of this was, that Mr
Pitt,
Pitt.
PIT [ 585 1 PIT
Pitt. Pitt, having received certain intelligence that the fa-
"'V'"""' mily-compatt was ligned between trance and Spain,
and that the latter was about to join Prance againlt us,
thought it neceffary to prevent her by commencing hof-
tilities firft. Having communicated this opinion in the
privy-council, the other minifters urged that they would
think twice before they declared war againft that king¬
dom. “ I will not give them leave to think (replied
Mr Pitt) ; this is the rime, let us cruth the whole houfe
of Bourbon. But if the members of this board are of a
different opinion, this is the iait time I fhall ever mix in
its councils. I was called into the miniitry by the voice
of the people, and to them I hold myfelf anfwerable for
my conduft. I am to thank the minifters of the late
king for their fupport •, I have ferved my country with
fuccefs j but I will not be refponfible for the conduct
of the war any longer than while I have the direbhon
of it.” To this bold declaration, the lord who then
preftded in council made the following reply. “ I find
the gentleman it determined to leave us ; nor can 1 fay
that I am forry for it, fince he would otherwiie have
certainly compelled us to leave him. But if he is re-
lolved to affume the right of advifing his majefty, and
directing the operations of the war, to what purpofe are
we called to this council ? When he talks of being
refponfible to thek people, he talks the language of the
houfe of commons, and forgets that at this board he is
relponfible only to the king. However, though he
may poftibly have convinced himfelf of his infallibility,
ftill it remains that we fhould be equally convinced be¬
fore we can refign our underftandings to his direction,
or join with him in the meafure he propofes.”
This converfation, which was followed by Mr Pitt’s
refignation, is futhcient to Ihow the haughtinefs and im¬
perious temper of our minifter. However, thefe very
qualities were fometimes produdtive of great and good
eonfequences, as appears from the following anecdote.
—Preparatory to one of the fecret expeditions during
the war which ended in 1763 the minifter had given
orders to the different prefiding officers in the military,
navy, and ordnance departments, to prepare a large
body of forces, a certain number of fhips, and a pro¬
portionable quantity of ftores, £kc. and to have them
all ready againft a certain day. To thefe orders he re¬
ceived an anfwer from each of the officers, declaring
the total impoffibility of a compliance with them.
Notwxthftanding it was then at a very late hour, he
fent immediately for his fecretary ; and after expreffing
his refentment at the ignorance or negligence of his
majefty’s fervants, he gave the following commands :
—“ I defire, Mr Wood, that you will immediately go
to Lord Anfon ; you need not trouble yourfelf to fearch
the admiralty, he is not to be found there ; you muft pur-
fue him to the gaming-houfe, and tell him from me, that
if he does not obey the orders of government which he
has received at my hands, that I will moft affuredlv im¬
peach him. Proceed from him to Lord Ligonier ; and
though he fhould be bolftered with harlots, undraw his
•urtains, and repeat the fame meffage. Then direfl your
courfe to Sir Charles Frederick, and affure him that if
his majefty’s orders are not obeyed, they flrall be the laft
which he {hail receive from me.” In confequence of
thefe commands, Mr Wood proceeded to White’s, and
told his errand to the firft lord of the admiralty ; who
infifted that the fecretary of flate was out of his fenfes,
Vol. XVI. Part II.
and it was impoffible to comply with his u iihes: “ how- Pitt’
ever, (added he), as madmen muft be anfwered, tell him l~—-v”—-3
that I will do my utmoft to fatisfy him.” From thence
he went to the commander in chief of the forces, and de¬
livered the fame meffage. He alfo faid that it was an
impoflible bufinefs $ “ and the lecretary knows it, (ad¬
ded the old lord) : neverthelefs, he is in the right to
make us do what we can 5 and what it is poffibte to do,
inform him, lhall be done.” The furveyor general of
the ordnance was next informed of Mr Put’s relolution ;
and, after fome little confideration, he began to think
that the orders might be completed within the time pre-
fcribed. The conlequence at laft was, that every thing,
in fpite cf impoffibilities themfelves, was ready at the
time appointed.
After his refignation in 1761, Mr Pitt never had any
{hare in adminiitration. He received a penfion of 3000I.
a-year, to be continued after his deceale, during the fur-
vivancy of his lady and fon ; and this gratuity was dip--
nined with the title of Baronefs of Chatham to his lady,
and that of Baron to her heirs male. Mr Pitt at that
time declined the title of nobility •, but in 1766 accepted
of a peerage under the title of Baron Pynjent and Earl
oj Chatham, and at the fame time he was appointed lord
privy-feal.
I his acceptance of a peerage proved very prejudicial
to his lordlhip’s charafter. However, he continued fled-
faft in his oppofition to the meafures of adminiftration.
His laft appearance in the houfe of lords was on the 2d
of April 1778. He was then very ill and much debili¬
tated : but the queftion was important, being a motion
of the duke of Richmond to addrefs his majefty to remove
the minifters, and make peace with America on any
terms. His lordfhip made a long fpeech, which had cer¬
tainly overcome his fpirits : for, attempting to rife a fe-
cond time, he fell down in a convulfive fit 5 and though
he recovered for that time, his diforder continued to in-
creafe till the 1 ith of May, when he died at his feat at
Hayes. His death wras lamented as a national lofs. As
foon as the news reached the houfe of commons, which
was then fitting, Colonel Barre made a motion, that an
addrefs ftiould be prefented to his majefty, requefting
that the earl 01 Chatham fhould be buried at the public
expence. But Mr Rigby having propofed the eredfing
of a^ ftatue to his memory, as more likely to perpetuate
the fenfe of his great merits entertained by the public,
this wras unanimoufly carried. A bill w'as foon after
paffed, by which 4000k a-year was fettled upon John
muv earl of Chatham, and the heirs of the late earl
to whom that title may defeend.—His lordftiip was
married in 1754 to Lady Hfcfter, filler to the earl
of Temple j by whom he had three fons and two
daughters.
Never perhaps was any life fo multifarious as that of
Lord Chatham ; never did any comprife fuch a number
of interefting fituations. To bring the fcattered fea¬
tures of fuch a charadfer into one point of view, is an
arduous talk. I he author of the hiftory of his life * ^ Ht/toryof
has attempted to do it; and with the outlines of what ^ Life °f
he has faid in fumming up his charadfer, w^e {hall finiftt Tilt*Earl
our biographical fketch of this wonderful man. of Chatham.
“ One of the firft things that ftrikes us, in the re¬
collection of Chatham’s life, is the fuperior figure he
makes among his cotemporaries. Men of genius and
attradlion, a Carteret, a Towmffiend, and I had almoft
4 E faid
P I T [ 586 ] P 1 T
laid a Mansfield, however pleafing in a limited view, ap¬
pear evidently in this comparifon to finink into narrow¬
er dimenfions, and walk a humbler circle. All that de-
lerves to arreft the attention, in taking a general furvey
ot the age in which he lived, is comprifed in the hiilory
of Chatham. No character ever bore the more undifput-
ed flamp of originality. Unrefembled and himfelf, he
was not born to accommodate to the genius of his age.
While all round him were deprefied by the uniformity
of faihion, or the contagion of venality, he flood aloof.
He coniulted no judgement but his own ; and he afted
from the untainted chelates of a ccmprehenfive foul.
“ The native royalty of his mind is eminently con-
fpicuous. He felt himfelf born to command j and the
tree Tons of Eritain implicitly obeyed him. In him w'as
realifed the fable of Orpheus j and his genius, his fpirit,
his eloquence, led millions in his train, lubdued the rug¬
ged lavage, and difarmed the fangs of malignity and
envy. Nothing is in its nature fo inconfillent as the
breath of popular applaufe : and yet that breath was
eminently his during the greater part of his life. Want
of fuccels could not divert it; inconfiltcncy of conduct
could not change its tenor. The aftonifhing extent of
his views, and the myllerious comprehenfion of his plans,
did not in one refpeft fet him above little things : no¬
thing that was neceflary to the execution of his defigns
■was beneath him. In another refpefl, however, he was
infinitely eflranged to little things : {wallowed up in the
bufinefs of his country, he did not think of the derange¬
ment of his own private affairs ; for, though indifpofed to
• all the inodes of difiipated expence, his affairs, ev«n when
his circumftances w7ere much improved, were always de¬
ranged. But the features that feem moft eminently to
have characterifed him, were fpirit and intrepidity : they
are confpicuous in every aftion and in every turn of his
bfe } nor did this fpirit and intrepidity leave him even
at the laft.
“ The manners of Lord Chatham were eafy and bland,
Ins converfation was fpirited and gay, and he readily
adapted himfelf to the complexion of thofe with whom
he affociated. That artificial referve, which is the never-
failing refuge of felf-diffidence and cowardice, was not
made for him. He was unconllrained as artlefs infancy,
and generous as the noon-day fun : yet had he fomething
impenetrable that hung about him. Ey an irrefiltible
energy of foul, he was haughty and imperious. He was
incapable of affociating councils, and he was not formed
for the fweeteft bands of fociety. lie was a pleafing
companion, but an unpliant friend.
“ The ambition cf our hero, however generous in its
ftrain, was the fource of repeated errors in his conduct,
lo the refignation of Lord Carteret, and again, from the
commencement of the year 1770, his-proceedings were
bold and uniform. In the intermediate period they were
marked with a verfatility, incident only in general to the
moff flexible minds. We may occafionally trace in them
the indecifion of a candidate, and the fupplenefs of a cour¬
tier. In a word, he aimed at the impoflible talk of flat¬
tering at once the prejudices of a monarch, and purfuing
unremittedly the interefts cf the people.
“ A feature, too, fufhciently prominent in his cha-
radler, was vanity, or perhaps pride and confcious fu-
periority. He dealt furely fomewhat too freely with
invedlive. He did not pretend to an ignorance of his
talents, or to manage the difplay of his important fer-
j
vices. Himfelf was too often the hero of his tale 5 and
the fucceffes of the lalt war the burden of his fong f.
“ Palriothm was alfo the fource of fome of his im-
perfedlions, Pie loved his country too well; or, if that
may found abfurd, the benevolence at leaft, that em¬
braces the fpecies, had not fufficient fcope in his mind.
He once fly led himfelf a lover of honourable war ; and-
in fo doing he let us into one trait of his charadler.
'The friend of human kind will be an enemy to all war.
He indulged too much a puerile antipathy to the houfe of
Bourbon ; and it was furely the want of expanfive affec¬
tions that led him to fo unqualified a condemnation of
American independency.
“ But the eloquence of Lord Chatham was one of his
moft linking charadleriftics. He far outftripped his com¬
petitors, and flood alone the rival of antiquity.
“ Plis eloquence was of every kind. No man excelled
him in clofe argument and methodical dedu&ion : but
this was not the ftyle into which he naturally fell. His
oratory was unlaboured and fpontaneous : he ruflied at
once upon the fubjedl 5 and ufuaily illuftrated it rather
by glowing language and original conception, than by
cool reafoning. His perfon was tall and dignified ; his
face was the lace of an eagle 5 his piercing eye withered
the nerves, and looked through the fouls of his oppon¬
ents ; his countenance was ftern, and the voice of thunder
fat upon his lips : anon, however, he could defeend to
the eafy and the playful. His voice feemed fcarcely more
adapted to energy and to terror, than it did to the me¬
lodious, the infinuating, and the fportive. If, however,
in the enthufiafm of admiration, we can find room for
the frigidity of criticifm, his aclion feemed the moft open
to objection. It was forcible, uniform, and ungraceful.
In a word, the moft celebrated orators of antiquity were
in a great meafure the children of labour and cultivation.
Lord Chatham was always natural and himfelf.”
To the misfortune of letters, and of pofterity, it has
been faid, his lordfhip never publilhed any thing. Lord
Chefterfield fays, “ that he had a moft happy turn for
poetry : but it is more than probable that Chefterfield
was deceived ; for we are told by his biographer that
his verfes to Garrick were very meagre, and Lord Cha¬
tham himfelf faid that he feldom indulged and feldoip
avowed it. It fliauld feem, then, that he himfelf fet
no great value upon it. Perhaps a proper confidence
of one’s fell is effential to all extraordinary merit.
Why fhould we ambitioufly aferibe to one mind every
fpecies of human excellence ? But though he was no
poet, it is more than probable, that he would have ex¬
celled as much in writing profe as he did in fpeaking
it.
Pitt, /he Right Honourable William, was the fourth
child of that illuflrious orator and confummate ftatefman,
William Pitt, the fiift earl of Chatham, and was born
on the 28th of May 1759. Nicholas Pitt, who lived
in the reign of Henry VI. was the common anceftor of
the noble families of Chatham, Camelford, and Rivers.
Thomas Pitt, the firft of the name who attained any
confiderable eminence, was governor of Fort St George
in the Eaft Indies, where he purchafed, as noticed in the
preceding life, for 20,400!. fterling, the extraordinary
diamond called the regent, weighing 127 carats, and
which was fold to the king of France for the enormous
fum of 135,000!. fterling. This diamond it is faid, now
occupies a confpicuous place in the imperial diadem of
Bonaparte*
Pitt.
f Ending in
i763*
PIT
Pitt. Bonaparle. By means of this vail fum he was enabled
—v—--1 to purchafe a confiderable eftate in Cornwall; yet his
grand-children were poorly provided for, particularly
the great earl of Chatham, but what he wanted in opu¬
lence was abundantly fupplied by the uncommon talents
and abilities, which nature conferred upon him in the
profufeft manner. Although he betook himfelf for fup-
port to the profeffion of arms, he never rofe higher than
to the rank of a comet of horfe, of which Sir Robert
Walpole, with unexampled meannefs, deprived him, be-
caufe he had the boldnefsand integrity to oppofe his ad-
miniftration. This, however, proved no real obftacle
to his preferment in the Hate, for in the year 1756 he
became prime minifter.
As the prefent earl of Chatham was deftined for the
army, and another fon James-Charles for the navy, lord
Chatham refolved to train up William to the profeffion
of a llatefman. Having therefore confided the care of
his other two fons to others, he took William under his
own immediate infpeftion, whofe rapid progrefs cheered
the folitude, and illumed the declining days of this ex¬
traordinary man, who already began to prefage his fu¬
ture greatnefs. His fchool exercifes were performed
tinder the care of a private tutor, a Mr, afterwards Dr
Wilfon, while his noble father embraced every oppor¬
tunity of converling with him on every interefting topic
with the utmoft freedom, in order to expand his mind,
and mature his judgement. He alfo made him declaim
from a chair or a table, well knowing that the gift of
eloquence is a valuable acquifition for a young man who
wifhes to arrive at eminence, and that it had fupplied the
deficiencies of fortune in his own perfon.
It was refolved on, at a proper period, to fend Wil¬
liam to one of the univerfities, and on this occafion Cam¬
bridge wras preferred to Oxford, from a decided opinion
entertained by many, that the political doctrines incul¬
cated at the former were more liberal than thofe ufually
propagated at the latter. He wTas accordingly placed
under the tuition of Dr Turner of Pembroke Hall. Dr
Prettyman, afterwards biffiop of Lincoln, alfo partici¬
pated in the care of his education, and was his private
inftruftor. During his refrdence at Cambridge, it ap¬
pears certain that the morals and conduct of Mr Pitt
were unimpeachable, not in the fmalleft degree contami¬
nated by the powerful example of the young nobility.
Here he took his bachelor’s degree, and alfo that of
A. M. and acquired fuch reputation in the univerfity for
talents, induftry, and propriety of deportment, as proved
of great advantage to him in his fubfequent purfuits
through life.
When Mr Pitt left the univerlity, he was entered at
Lincoln’s Inn, much about the fame time with Mr Ad¬
dington, whofe father had been both the phyfician and
friend of his family, and was enabled to be called to the
bar in the fpace of three years, having received fome
marks of favour on account of his degree. He made
choice of the weftern circuit as the fcene of his firft ef¬
forts •, but having little practice as an lawyer, he had of
confequence but little celebrity ; and it is probable that
he was ill qualified, on the fcore of patient and labo¬
rious inveftigation, for a purfuit in which nothing great
can be accomplifhed, without the perfevering indultry of
a whole life.
Fortune at this time feemed eager to heap favours
upon him of another kind. Being bred a ftatefman, the
P I T
houfe of commons was of courfe the place where he
was to begin his political career. He was advifed by
numerous friends to propofe himfelf a candidate for the
univerfity of Cambridge, but he failed of fuccefs from
the want of fufficient influence. Accident, howrever,
brought about wdiat the defigns of his friends could not
accomplifh. 'I he duke of Rutland alked Sir James Low-
ther (afterwards earl of Lonfdale), if he could poffibly
make room in any of his boroughs, to bring in his young
friend Mr Pitt, who had thus loft his election for Cam¬
bridge. He was chofen member for the borough of Ap¬
pleby. About this time the American war was raging
with unabated violence, which Mr Pitt, following the
example and advice of his father, reprobated as one of
the mold fhameful and ruinous corfiicfts of modern times.
Having efpouled the conftitutional and popular fide of
this important queftion, his opening talents were difplay-
ed to no common advantage, and he was not only re¬
garded as a promifing fpeaker, but as deftined at fome
future period to rank high in-the councils of his native
country. I his w as truly honourable to (o young a man,
when it is remembered that one houfe could then boafi:
oi a Rockingham, a Richmond, and a Shelburne, and
the other of a Saville, a Dunning, a Burke, a Barre,
and a Fox. Yet there was ftill rocm for our juvenile
orator, and the recolledlion of the eloquence, the talents,
and the meritorious fervices of his father, contributed
greatly to fix the attention of mankind on the deport¬
ment of a favourite fon.
About this time the extent of the royal prerogative
engaged the attention both of the parliament and the
public, and a vote of the commons, “ that the influence
of toe crown had increafed, vras increafing, and ought
to be diminilhed,” plainly pointed to an objeft, whether
real or imaginary, which occafioned a confiderable de¬
gree ot dilcontent. Mr Burke, then in the zenith of his
popularity, encouraged by numerous fymptoms of jea-
loufy, once more brought forward his plan of economy,
which being founded on a progreffive retrenchment, ap¬
peared admirably calculated to diminiffi the influence of
the crowm. It is needlefs to add that it was oppoled by
the minifler (Lord North), but it wras ably fupported bv
Air Pitt, who forcibly ridiculed every objtdlion that could
be brought againft it. The bill was rejefted after a
long debate, but afterwards introduced at a more aufni-
cious period, and to a certain extent carried into effetft.
. IH°X having moved that minifters ffiould imme¬
diately take every poffible meafure for concluding a
peace with 0111 American colonies, he wTas powerfully
fupported by Air Pitt, nffiofe commanding eloquence en¬
gaged the whole attention of the houfe, while he re¬
probated the cruelty and impolicy of the conteft with
our colonies. He declared that it wTas conceived in in-
juftice, nurtured and brought forth in folly, and its foot-
iieps were marked with blood, flaughter, perfecution,
and devaifation. Many handfome compliments were
paid him by two eminent judges of real merit, we mean
the lord advocate of Scotland (now Vifcount Melville)
and Air W ilkes. dhe former, in particular, declared that
his powerful abilities and brilliant eloquence were uni-
verfally acknowledged proofs, that the aftonifliing extent
and force of an exalted underftanding had defeended, in
an hereditary line, from the late illuftrious poffeffor of
them, to a fon equally endowed with all the fire, and
ftrength, and grace of oratory.
4 E 2
[ 587 1
A
P I T
Pitt.
A more equal reprefentation of the people in parlia¬
ment was one of the principal objefcs to which the na¬
tion direfted its attention, next to the American war.
It was admitted to be the undoubted prerogative of the
crown to declare war 5 but as the fupplics were entruited
to the management of the reprefentatives of the people,
it was affirmed by fome that miniders could not have
carried on a contell accompanied with the walte of fo
much blood and treafure, had it not been owing to the
corruption and venality of parliament. To derive ad¬
vantage from pall experience ; to confer on the people
their due importance in Inch a mixed government as
that of iiritain, and reilore the conftitution to its origi¬
nal purity, became by this time the grand objeft of Mr
Pitt’s exertions. He was as yet untainted by the faici-
Jiating charms of power and authority, and confidered a
well-earned fame as the heft, the only reward of his
laudable endeavours. He accordingly brought the prin¬
ciples and condudt of his opponents to i'uch a tell as they
fuccefsfully employed again)! himfelf, in order to wound
his feelings, and convxft him of inconfiflency, by turn¬
ing his back on his once favourite fentiments. When
many cities and counties endeavoured to obtain a reform
in parliament, Mr Pitt aftually fat in a convention of
delegates, met together in the neighbourhood of the
place where the legiflature held its fittings.
The American war in the mean time was drawing to
a termination, and the fpoils of the office of tire former
minifter became the reward of thofe who oppofed him.
During the fhort exiftence of the Rockingham admini-
ftration, contractors were excluded from the houfe of
commons; officers belonging to the cutfoms and excife
were declared unqualified to vote at eledlions; the pro¬
ceedings refpecting the Middlefex election were refeind-
ed : and while a more liberal policy was adopted with
regard to Ireland, many fuperfluous offices were aboliffi-
ed in England by means of a reform bill, which tended
powerfully to deftroy corruption. -Many more import¬
ant reforms would have been accomplifhed, had not the
death of the diftinguiffied Rockingham brought about
great and fudden changes.
Mr Fox retired in confequence of new arrangements,
and Lord Shelburne, as firft lord of the treafury, made
choice of Mr Pitt as chancellor of the exchequer, who,
declared, although only 23 years of age, that he would
accept of no inferior office. Peace now' feemed to be an
objedt generally defirable at any rate, and without much
regarding what facrifices might be made in order to pro¬
cure it; but the terms met with powerful oppofition
from two men formerly confidered as mortal enemies,
viz. Lord North and Mr Fox, the latter of whom retired
from office. Soon after the difmiffion of Mr Fox, Mr
Pitt again brought forward the quefiion refpedling a re¬
form in parliament, wffiich he fondly hoped would be
the means of reftoring him to his wonted popularity, and
pave the way to the increafe of his power. He therefore
fubmitted three different motions to the 'confideratiq;r of
the houfe ; but although in thefe motions he wras ably
Supported, he v,Tas left in a minority.
The coalition miniftry, as it w^as called, had ftill a
confiderable majority in parliament, notwithftanding the
popularity belonging to the name and talents of Mr Pitt,
but the celebrated India bill wTas productive of a change.
This bill owTed its origin to Mr Burke, but it received a
regular and fyftemadcal oppofition from the ex-chancel-
[ 588 ]
PIT
lor of the exchequer: It was carried, however, in the
houfe of commons by a great majority, but in the houfe
of lords it was oppoied by the duke of Richmond, Lord
Thyrlow, and Earl Temple (afterwards marquis of Buck¬
ingham) ; and on the 17th of December 1783, it was
finally rejected by a majority of 19.
J he king in the mean time determined on an entire
change of adminiftration, and the two fecretaries were
informed on the 18th of December 1783, about 1 2 o’clock
at night, that his majefly had no further occafion for
their fervices. In confequence of this change, the im¬
portant offices of firfl lord of the treafury and chancellor
of the exchequer were bellowed on Mr Pitt, who thus
became prime minifter before he was full 24 years of ape.
1 hurlow was created lord chancellor, the duke of Rich¬
mond keeper of the privy feal ; the marquis of Caermar-
then and Lord Sidney were chofen fecretaries of Hate, and
Mr Dund as, treafurer of the navy.
Much about this time Mr Pitt brought forward a
new7 bill for the better government of India. lie pro-
pofed that a board of controul fhould be inftituted, the
nomination of whofe members w as to be veiled in the
crowm, and to them the difpatches of the company were
to be fubmitted. lie alfo propofed that the appointment
of the commander in chief fhould belong to his majefly,
and having thus fecured the political interefts of the
company, he left thofe of a commercial nature entirely
to the court of directors. This bill, after a fhort debate,
w'as rejected by a majority of eight. Such was the pre¬
fect temper of the houfe of commons, that a coalition or
immediate diflblution became abfolutely neceffary ; and
the former having been unfuccefsfully attempted, the
latter w7as fuddenly adopted, on the 25th of March 1784.
Mr Pitt having been returned for the univerfity of Cam¬
bridge, again brought forward his bill in an amended
ftate for the regulation of India, and carried it in triumph
through both houfes of parliament. The remaining part
of the feffion gave birth to an aft for the better preven¬
tion of fmuggling, and the commutation a61, by virtue
of which certain duties were transferred from tea to
windows.
When Mr Alderman Saw'bridge (June 16th 1784)
made a motion for inquiring into the prefent ftate of the
commons of Great Britain in parliament, Mr Pitt, whofe.
political fentiments had undergone a revolution, felt him¬
felf confiderably embarraffed, as he vras reminded that
he had brought forward queftions on the fame fubjecl
upon a former occafion. Mr Pitt, however, declined it,,
on account of the preffure of public bufinefs, and ob-
ferved that, in his opinion, the prefent w as not the pro¬
per time for bringing forward the queftion, and that it
might be urged with greater probability of fuccefs on
fome future occafion. He did not wiffi it to be dif-
cufied in a precipitate manner, yet the bufinefs itfelf
fhould have every fupport he wras able to afford it.
Having now attained the fummit of pow'er and influ¬
ence as prime minifter, Mr Pitt exercifed every function
of his important office, without any check or controul..
Poffeffed of a great majority in both houfes of parlia¬
ment, as w ell as in the cabinet, his whole deportment,
in the language of his opponents, feems to have become,
lofty in the extreme ; and he paid little or no regard to
that popularity which he had formerly courted.
A commercial treaty about this time was entered into
with France, the term? of which have been generally.
acknowledged
PIT r ;
acknowledged to be advantageous to Britain. Mr Pitt,
who deferves great credit for giving the plan his coun¬
tenance, adopted, much about the fame time, another
refpefting the finances, from which he derived a high
degree of reputation ; and, as he pointed at a period
when the national debt might, in all probability, be ex-
hinguifhed, the country, if it was not altogether fatis-
fied, appeared to be at leaft contented under his admini-
llration : and it is not a little to the credit of his finan¬
cial fyltem, that his opponents, when in power, not on¬
ly approved, but adopted and extended it.
in this manner a commercial country began again to
fiounih, by turning its attention to the arts of peace j
but, during his adminiftration, its profperity was threat¬
ened to be interrupted by the preparations for an attack
upon Ruffia at one time, and by an open rupture with
Spain at another, relative to Nootka found. In both
cafes the blow was warded olf by negociation, and a
good underftanding reftored. The reftoration of the
itadtholder, by the intervention of a Pruffian army, and
his ftrenuous oppofition of the prince of Wales’s appoint¬
ment to the regency during the king’s indifpofition,
were alfo two important meafures purfued and dikuifed
in the courfe of his mlniftry.
Soon after the commencement of the French revolu¬
tion, Mr Pitt deemed a war with that country inevi¬
table. But for a full detail of the events of this war,
fee Britain. Having held the reins of government
during 18 years, Mr Pitt, and all the members of the
cabinet, fuddenly retired from office in 1801. On this
occafion all parties appeared to rejoice at the appoint¬
ment of Mr Addington j and France, from that mo¬
ment, as fome affert, feemed to have neither friends nor
advocates in this ifland. When the articles of the treaty
of Amiens were debated in the houfe of commons, Mr
Pitt defended the new miniiter with the whole force of
his abilities and influence.
On the 15th of March 1804, Mr Pitt made a direct
attack on the adminiftration ; and the admiralty board
was accufed by him of imbecility. He zealoufly fup-
ported PTr Fox’s propofition relative to the Irifh militia
bill for the national defence, which was loft on a divi-
lion. The minitter’s majority having dwindled to 37,
on the army of referve fufpenfion bill, Mr Addington
and fome of his friends retired, and the ex-minifter re¬
fumed his former feat. When parliament met on the
19th of January 1805, Mr Pitt warmly defended the
war with Spain 5 and, on the motion for an addrefs, he
had a majority of 207.
But, in the mean time, a gouty habit, the predifpo-
fing caufes of which appear to have been hereditary,
and which, perhaps, was increafed by his own manner
of living, feized on a conftitution never very ftrong. It
is alleged, by his opponents, that this, combined with
the mifearriage of his fchemes, and the afpeft of affairs
on the continent, preyed fo much upon his mind, that
he is faid to have died of a broken heart, at his houfe
near Putney, between four and five on Wednefday
morning, January 23. 1806, in the 47th year of his
age.
As a financier, no man has obtained more praife,
who ever prefided at the board of exchequer. During
his miniftry fome of our manufactures languifhed, but
many flouriftied, ani our exports were greatly increafed.
As a fpeaker he was unrivalled, and his generous fcorn
89 1 PI T
of wealth muft be admired. In 20 years Ins debts a-
mounted only to 40,000!. They were paid out of the
public purfe. The houfe of commons alfo paffed a vote,
that the expences of his funeral, and a monument to his
memory, ftiould be defrayed by the nation.
PIT TAG US, a native of Mitylene in Lefbos, was
one of the feven wife men of Greece : his father’s name
was Hyrradius. With the afliftance of the fons of Al¬
caeus, he delivered his country from the oppreftion of the
tyrant Melanchrus ; and in the war which the Atheni¬
ans waged againft Lefbos, he appeared at the head of
his countrymen, and challenged to fingle combat Phry-
non the enemy’s general. As the event of the war
feemed to depend upon this combat, Pittacus had re-
courfe to artifice ; and when he engaged, he entangled
his adverfary in a net which he had concealed under his.
ftiield, and ealily difpatched him. He was amply re¬
warded for this victory ; and his countrymen, fenfible of
his merit, unanimoufly appointed him governor of their
city with unlimited authority. In this capacity Pittacus
behaved with great moderation and prudence ; and after
he had governed his fellow-citizens with the ftriCteft ju-
ftice, and after he had eftablifhed and enforced the moft
falutary laws, he voluntarily refigned the fovereign
power after having enjoyed it for 10 years, obferving,
that the virtues and innocence of private life were in¬
compatible with the power and influence of a fovereign..
His difintereftednefs gained him many admirers; and
when the Mityleneans wiftied to reward his public fer-
vices by prefenting him with an immenfe trad of terri¬
tory, he refufed to accept more land than what fhould-
be contained in the diftance to which he could throw a
javelin. He died in the 70th year of his age, about.
579 years before Chrift, after he had fpent the laft
10 years of his life in literary eafe and peaceful retire¬
ment.
The following maxims and precepts are aferibed to
Pittacus : The firft office of prudence is to forefee threat¬
ening misfortunes, and prevent them. Power difeovers
the man. Never talk of your fchemes before they are
executed ; left, if you fail to accomplifh them, you be
expofed to the double mortification of difappointment
and ridicule. Whatever you do, do it well. Do not
that to your neighbour which you would take ill from
him. Be watchful for opportunities.
Many of his maxims were inferibed on the walls of:
Apollo’s temple at Delphi, to fhow to the world how
great an opinion the Mityleneans entertained of his
abilities as a philofopber, a moralift, and a man. By
one of his laws, every fault committed by a man when
intoxicated deferved double punifhment.
PITTENWEEM, a fmalltown fituated on the frith
of Forth, towards the eaftern extremity of the county of
Fife in North Britain. It takes its name from a final!
cave in the middle of it, anciently called a weem; and is
remarkable for nothing but the ruins of a religious houfe,
which is fometimes called an abbey and fometimes a
priory. Which of thefe is the proper denomination it is
hardly worth while to inquire ; but it appears from the
arms of the monaftery, ftill preferved over the principal
gate, that the fuperior, by whatever title he was called, ,
had the privilege of wearing a mitre. This edifice,,
which feems never to have been large, was, with other
monuments of miftaken piety, alienated from the church
at the,Reformation} and -what parts of it now remain
fit r 590 i p 1 11
Titten- are put to very different ufes. Some of tire cells of tlie
^ weern. monks furnidr habitations tolerably convenient for the
v fervants of him who, in the ceafeleis change of property,
has got poffeflion of the lands which formerly belonged
to them. That which feems to have been the granary
is a decent pariih church. The porch of the chapel,
the only part of that building which exifts, has been al¬
ternately employed as a (table and a flaughter-hdufe j
and the meat killed there has been commonly expofed to
fale in the lower part of the fteeple of that edifice which
is now dedicated to the offices of parochial devotion.
# Johnfon. Had the moralizing traveller *, who compofed the beau¬
tiful and pathetic meditation on the ruins of /one, con-
defeended to vifit Pittenweem, he would not have view¬
ed the abbey without emotion. Infignificant as the
place at prefent is, it feems to have been of fome confe-
quence in the laft century ; and we are led to infer,
from the following extraft from the records, that the
inhabitants were opulent, and that the town was for¬
tified.
“ Pittenweem, decimo quarto Feb. 1651. The bai¬
lies and council being convened, and having*received in¬
formation that his majefty is to be in progrefs with his
court along the coaft to morrow, and to (lay at Anftru-
ther houfe that night, have thought it expedient, ac¬
cording to their bounden duty, with ail reverence and
due refpedl, and with all the fame folemnity they can,
to wait upon his majefly, as he comes through this his
majefty’s burgh, and invite his majelly to eat and drink
as he paffes j and for that effe£l hath ordained, that the
morn afternoon the town’s colours be put upon the ber-
tifene of the fteeple, and that at three o’clock the bells
begin to ring, and ring on dill till his majefty comes hi¬
ther, and paffes to Anftruther : And ficklike, that the
minifter be fpoken to, to be with the bailies and coun¬
cil, who are to be in their bed apparel, and with them
a guard of 24 of the ableft men, with partizans, and
other 24 with mufkets, all in their beft apparel, Wil¬
liam Sutherland commanding as captain of the guard j
and to wait upon his majefty, and to receive his high-
nefs at the Weft Port, bringing his majefty and court
through the town, until they come to Robert Smith’s
* The Earl yeet, where an table is to be covered with my Lord’s *
Kelly, beft carpet: and that George Hetherwick have in rea-
dinefs, of fine flour, fome great bunns, and other wheat-
bread of the beft order, baken with fugar, cannell, and
other fpices fitting •, and that James Richardfon and
Walter Airth have care to have ready eight or ten gal¬
lons of good ftrong ale, with Canary, fack, Rheniffi
/ wine, tent, white and claret wines, that his majefty and
his court may eat and drink j and that in the mean
time, when his majefty is prefent, the guard do dili¬
gently attend about the court *, and fo foon as his maje¬
fty is to go away, that a fign be made to Andrew Tod,
who is appointed to attend the colours on the fteeple
head, to the effedl he may give fign to thofe who attend
the cannon of his majefty’s departure, and then the haill
thirty fix cannons to be all pot at once. It is alfo thought
fitting, that the minifter, and James Richardfon the old-
eft bailie, when his majefty comes to the table, (how
the great joy and fenfe this burgh has of his majefty’s
condefcendence to vifit the fame, with fome other ex-
preffions of loyalty. All which was a£ted.” The po¬
pulation of this town, in 1790, was computed at 1157*
Jf. Lat. 56. 11. W. Long. 2. 49.
3
PITTOSPORUM, a genus of plants belonging to Pittoipe-
the pentandria clafs. See Botany Index. riim
PITUITARY gland. See Anatomy Index. J1
PITYOCAMPASIS, in Entomology, the caterpillar ^
of the pine-tree, received its compound name from that
fubftance. It was confidered as a poifon, and as a re^
medy, according to its different mode of application.
Our chief information, concerning this caterpillar, is de¬
rived from M. Reaumur, who has attentively obferved
its manner of life. The animal cannot bear much cold,
and is therefore never found in the higher latitudes. It
is ftyled proceffionary, becaufe it never leaves its hold,
where many families refide, till the evening, when it
feeds in trains, led on by two or three, and this train
leaves a ribband of (ilk in its way j for thofe behind fol¬
low exaflly the fteps of thofe which preceded, and each
leaves its fibre of (ilk. Their nefts are found in au¬
tumn ; they are produced in the middle of September,
become torpid in December, and recover their ftrength
again in fpring. They then defeend from the trees,
plunge into the earth, and undergo their laft change.
It is the bombix pityocampa of Fabricius, {Mantijfia In-
fieBor. tom. ii. p. 114. N° 66.), and greatly refembled
the proceffionary caterpillar of the oak. The ancients
ufed it as a veficatory, and the acrimony feems to refide
chiefly in a duft which is concealed in receptacles on its
back. This is its offenfive weapon, for it is thrown out
at will, and produces very troublefome effe&s, though
the hair of the animal and every part of its body feem to
have a fimilar, but weaker power. The effeft is alfo
weaker in winter 5 but this may depend on the diminifti-
ed irritability of the human body, as well as on the tor¬
pid (late of the infeft. Their (ilk is not fufficiently
ftrong for the loom, and in hot water melts almoft to a
pafte. In the earth it forms nefts of ftronger (ilk, but
it is then found with difficulty : in boxes its (ilk is ex¬
tremely tender. Adding to all thefe inconveniences,
handling the cones produces all the bad effe&s of the
duft. Matthiolus recommends them as a ftyptic, and
perhaps they may ferve for burning on the (kin inftead
of moxa, the downy filk of a fpecies of artemifia. The
ancients, afraid of its hurtful qualities, ufed them with
caution, and enadted laws againft their being fold pra-
mifeuoufly : the modern planter is chiefly afraid of them,
becaufe they deftroy the beauty of his trees, and he en¬
deavours to colledt the eggs by cutting off the branches,
which are burnt immediately.
PIVAT, or Pivot, a foot or (hoe of iron or other
metal, ufually conical or terminating in a point, where¬
by a body, intended to turn round, bears on another
fixed at reft, and performs its revolutions. The pivot
ufually bears or turns round in a foie, or piece of iron
or brafs hollowed to receive it.
PIUS II. (Alneas-Sylvius Piccolomini), was bom
on the 18th of Odlober 1405, at Corfigm in the Sienefe,
the name of which he afterwards changed into that of
Pienza. His mother Victoria Forteguerra, when (he
was with child of him, dreamed that (he (hould be deli¬
vered of a mitred infant; and as the way of degrading
clergymen at that time was by crowning them with a
paper mitre, (he believed that Atneas would be a dif-
grace to his family. But what to her had the appear¬
ance of being a difgrace, was a prefage of the greateft
honours. iEneas was carefully educated, and made
conlxderable proficiency in the belles lettres. After ha¬
ving
p I u [ 591 ] P I U
Pius, ving Snlflied his ftudies at Sienna, he went in 1431 to
the council of Bale with Cardinal Capranica, furnamed
De Fe> ■mo, becaufe he was entrufted v,rith the govern¬
ment of that church. jfiE.neas was his fecretary, and
was then only 26 years of age. He afterwards afted in
the fame capacity to ibme other prelates, and to Cardi¬
nal Albergati. The council of Bale honoured him with
different dommiflions, in order to recompenfe him for
the zeal with which he defended that alfembly againlt
Tope Eugene IV. He was afterwards fecretary to Fre¬
deric III. who decreed to him the poetic crown, and
lent him ambaffador to Rome, Milan, Naples, Bohe¬
mia, and other places. Nicholas V. advanced him to
the bifhopric of Triefle, which he quitted feme time
after for that of Sienna. At lail, after having diilin-
guifhed himfelf in various nunciatures, he was inverted
with the Roman purple by Calixtus III. whom he fuc-
ceeded two years after, on the 27th of Augurt 1458.
Pius II. norv advanced to the holy fee, made good the
proverb, Honores mutant mores. From the commence¬
ment of his pontificate, he appeared jealous of the papal
prerogatives. In 1460 he iffued a bull, “ declaring ap¬
peals from the pope to a council to be null, eroneous,
deteftable, and contrary to the facred canons.” That
bull, however, did not prevent the procurator-general
of the parliament of Paris from appealing to a council in
defence of the Pragmatic Sanftion, which the pope had
rtrenuoully oppofed. Pius wTas then at Mantua, whither
he had gone in order to engage the Catholic princes to
unite in a wTar againft the Turks. The greater part of
them had agreed to furnirti troops or money ; others re-
iufed both, particularly France, who from that moment
incurred his holinefs’s averfion. That averfion abated
under Louis XL whom he perfuaded in 1461 to abo-
lilh the Pragmatic Sanflion, wdiich the parliament of
Paris had fupported with fo much vigour.
The following year 1462, w?as rendered famous by a
controverfy wThich took place between the Cordeliers
and Dominicans, whether or not the blood of Jefus
Chrift was feparated from his body while he lay in the
grave. It was alfo made a queftion'whether it was fe¬
parated from his divinity. The Cordeliers affirmed that
it was, but the Dominicans wrere of an oppofite opinion.
They called each other heretics 5 which obliged the
pope to iffue a bull, forbidding them under pain of cen-
fure to brand one. another with fuch odious epithets.
The bull which his holinefs publifhed on the 26th of
April, retracting what he had written to the council of
Bale rvhen he wras its fecretary, did not redound much
to his honour. “ I am a man (fays he), and as a man
I have erred. I am far from denying that a great ma¬
ny things which I have faid and written may deferve
condemnation. Like Paul, I have preached through
deception, and I have perfecuted the church of God
through ignorance. I imitate the bleffed Auguftin, who
having fuffered fome erroneous fentimenls to creep into
his works, retraced them. I do the fame thing; I
frankly acknowdedge my ignorance, from a fear left
wffiat I have w'ritten in my younger years fliould be the
occafion of any error that might afterwards be prejudi¬
cial to the interefts of the holy fee. For if it be proper
for any one to defend and fupport the eminence and glo¬
ry of the firft throne of the church, it is in a peculiar
sianner my duty, whom God, out of his mercy and
goodnefs alone, without any merit on my part, has rai-
fed to the dignity of vicar of Jefus Chrijl. For all thefe
reafons, w'e exhort and admonilh you in the Lord, not
to give credit to thole writings of ours which tend in any
degree to hurt the authority of the apoltolic fee, and
whicn eftablilh opinions that are not received by the Ro¬
man church. If you find, then, any thing contrary to
her doClrineq either in our dialogues, in our letters, or in
other 01 our works, delpife thele opinions, rejefl them,
and adept our prefent fentiments. Believe me rather
now that I am an old man, than when I addrefled you
in my earlier days. Efleem a fovereign pontiff more
than a private perfon ; except againft riEneas Sylvius,
but receive Pius II.” It might be obje&ed to his holi¬
nefs, that it w’as his dignity alone which had made him
alter his opinion. Fie anticipates that obje&ion, by giv¬
ing a ftiort account of his life and actions, wdth the whole
hiltory of the council of Bale, to which he went wdth
Cardinal Capranica in 1431 j “ but (fays he) I was then
a young man, and without any experience, like a bird
juft come from its neft.” In the mean time, the Turks
were threatening Chrirtendom. Pius, ever zealous in
the defence of religion againft the infidels, forms the re-
folution of fitting out a fleet at the expence of the church,
and of parting over into Alia himfelf, in order to ani¬
mate the Chriftian princes by his example. He repaired
to Ancona with a defign to embark; but he there fell
fick wfith the fatigue of the journey, and died on the
16th of Auguft 1464, aged 59 years. Pius was one
of the moft learned men of his lime, and one of the moll
zealous pontiffs ; but being of an ambitious and pliant
difpofilion, he fometimes facrificed to that ambition.
His principal wmrks are, 1. Memoirs of the council of
Bale, from the fufpenfion of Eugenius to the ele&ion of
Felix. 2. The hiftory of the Bohemians, from their
origin to the year 1458. 3. Two books on cofmogra-
phy. 4. The hiftory of Frederic III. whofe vice-chan¬
cellor he had been. This performance wTas publifhed in
1785 in folio, and is believed to be pretty accurate and
very particular. 5. A treatife on the education of chil¬
dren. 6. A poem upon the paffion of Jefus Chrift.
7- A collation of 432 letters, printed at Milan, 1473,
in folio, in which are found fome curious anecdotes.
8. The memoirs of his owm life, publifhed by John Go¬
belin Perfonne his fecretary, and printed at Rome in 410
in 1584. There is no doubt of this being the genuine
production of that pontiff. 9. Hiforia rerum ubicumque
gefarum, of which only the firft part w'as publiftied at
Venice in 1477 in folio. His works were printed at
Flelmftadt in 1700, in folio, at the beginning of which
we find his life. That verfe of Virgil’s riEneid (lib. i.
382.) which begins thus,
Sum phis JEncas,   
and the end of the following verfe,
  fama fuper cethera not us,
have been applied to him.
Pius IV. { John Angel, Cardinal de Medicis), of a dif¬
ferent family from that of Florence, was born at Milan
in 1499. He was fon to Bernardin de Mcdcchini, and
brother of the famous Marquis de Marignan, Charles
V.’s general. He raifed himfelf by his own merit,
and filled feveral important offices under Popes Clement
VII. and Paul III. Julius III. who had entrufted him
with feveral legations, honoured him with a cardinal’s
hat-
p i u r 592 i pi u
hat in 1549. After the death of Paul IV. he was ad¬
vanced to Sr Peter’s chair on the 25th of December
1559. His predeceffor had rendered himfelf deteftable
to the Homans, who treated his memory with every
mark of indignity, and Pius IV. commenced his pontifi¬
cate by pardoning them. He did not, however, extend
the fame clemency to the nephews of Pope Paul IV. j
for he caufed Cardinal Caraffe to be Itrangled in the
caftle of St Angelo, and his brother, the prince de Pal-
liano, to be beheaded. His zeal was afterwards direct¬
ed againft the Turks and heretics. In order to flop, if
poffible, the progrefs of thefe lait, he renewed the Coun¬
cil of Trent, which had been fufpended. He knew7
well (fays Abbe de Choify), that that council might
make fome regulations which w ould have the effeCt to
leifen his authority j but, on the other hand, he perceiv¬
ed that great inconveniences might refult from its not
being afl’embled •, and “ in the ma.n (faid he to his con¬
fidants! it is belt a- to feel evil for once uhan to be always
in dread of it.''"> In 1561 he difpatched nuncios to all
the Catholic and Proteilant princes, to prefent them with
the bull for calling that important alfembly. An end
was, however, put to it by the induftry of his nephew,
S. Charles Borrcmeus, in 1563} and, on the 26th of
January the year following, he ifiued a bull for confirm¬
ing its decrees. In 1563' a confpiracy was formed
againft his life by Benedict Acolti, and fome other vi-
fionaries. Thofe madmen had taken it into their head
that Pius IV. was not a lawful pope, and that after his
death they would place another in St Peter’s chair, with
the title of Tope Angelicas, under whom errors might be
reformed, and peace reftored to the church. The con¬
fpiracy wras difeovered, and the fanatic Benedict put to
death. This pontiff died a little time after, on the 9th
of December 1565, aged 66 years, carrying to the
grave wdth him the hatred of the Homans, whom his
feverities had exafperated. He was a man of great ad-
drefs, and very fruitful in his refources. He adorned
Rome with feveral public edifices j but thefe ornaments
tended greatly to impoverifti it. If he was the inftru-
ment of railing his relations in the wmrld, it muft be al-
knved, at leait, that the greater part of them did him
honour.
Pius V. (.S. Michael Glifieri), born at Bofchi or Bof-
co, in the diocefe of Fortona, on the 17th of January
1504, wras, according to Abbe de Choify, fon to a fena-
tor of Milan. He turned a Dominican friar. Paul IV.
informed of his merit and virtue, gave him the biftiopric
of Sutri, created him cardinal in 1557, and made him
inquifitor-general of the faith among the Milanefe and
in Lombardy •, but the feverity with wdrich he exercifed
his office obliged him to quit that country. He was
fent to Venice, where the ardour of his zeal met with
ftill greater obftacles. Pius IV. added to the cardinal’s
hat the bilhopric of Mwndovi. After the death of that
pontiff, he w7as advanced to St Peter’s chair in 1 566.
The Romans expreffed but little joy at his coronation :
he w7as very fenfible of it, and faid, “ I hope they will
be as forry at my death as they are at my clecUon but
he was miftaken. Haifed by his merit to the firft eccle-
fiaftical preferment in Chriftendom, he could not diveft
himfelf of the feverity of his charaCler ^ and the fituation
in which he found himfelf rendered, perhaps, that feve¬
rity neceflary. One of his firft objeCls was to reprefs
the luxury of the clergy, the pride of the cardinals, and
2
the licentious manners of the Romans. Fie caufed the Pi
decrees of reformation enaCted by the Council of Trent
to be put in execution ; he prohibited bull-baiting in
the Circus) he expelled from Rome the women of the
town 5 and allowed the cardinals to be profecuted for
their debts. The errors which overflowed the Chriilian
world gave him great uneafinefs. After having em¬
ployed gentle and lenient meafures in the reclaiming of
heretics, he had recourfe to feverily, and fome of them
ended their days in the flames of the inquilition. He
particularly dilplayed his zeal for the grandeur of the
holy fee in 1568, by ordaining that the bull In ccena
do mini, which was publifned at Rome every year on
Maunday Thurfday, and which Clement XiV. fup-
preffed, fliould be publilhed likewife throughout the
whole church. That bull, the work of feveral fove-
reign pontiffs, principally regards the jurifdicfion of the
ecclefiaftical and civil power. It anathematizes thole
who appeal from the decrees of popes to a general coun¬
cil ; thofe who favour the appellants} the univerfities
which teach that the pope is fubjedt to a general coun¬
cil ; the princes who would reftrain the ecclefiaftical ju-
rifdidion, or who ex ad contributions from the clergy.
It was rejeded by all the fovereign fta'es, excepting a
very few7. In 1580, fome bilhops having endeavoured
to introduce it into their diocefes, the parliament caufed
their temporalities to be feized upon, and declared thofe
guilty of high treafon who Ihould imitate the fanati-
cifm of thole prelates. Pius V. for fome time medi¬
tated an expedition againft the Turks. He had the
courage to make war on the Ottoman empire, by
forming a league with the Venetians and Philip II.
king of Spain. This was the firft time that the ftan-
dard of the two keys was feen difplayed againft the
crefcent. The naval armies came to an engagement,
on the 7th of Odober 1571, in Lepanto bay, in which
the confederate Chriftian princes obtained a fignal vic¬
tory over the Turks, who loft above 30,000 men, and
near 200 galleys. This fuccefs was principally owing
to the pope, who exhaufted both his purfe and perfon
in fitting out that armament. He died of the gravel
fix months after, on the 30th of April 1572, aged 68.
He repeated often, in the midft of his fufferings, “ O
Lord! increafe my pains and my patience.’1'1 His name
will for ever adorn the lift of Homan pontiffs. It is
true, that his bull againft Queen Elizabeth, and his
other bull in favour of the inquifition, with his rigorous
profecution of heretics both in France and Ireland,
prove that he had more zeal than fweetnefs in his tem¬
per •, but in other refpeds he poffeffed the virtues of a
faint and the qualities of a king. Pie was the model of
the famous Sixtus Quintus, to whom he gave an example
of amafling in a few years fuch favings as were fufficient
to make the holy fee be regarded as a formidable power.
Sultan Selim, who had no greater enemy than this pope,
caufed public rejoicings to be made at Conftantinople
for his death during the fpacc of three days. The, pon¬
tificate of Pius is alfo celebrated for the condemnation
of Baius, the extinction of the order of Humilies, and
the reformation of that of the Ciftercians. He w7as ca¬
nonized by Clement XL in 1712. There are extant
feveral of his letters, printed at Anvers in 1640, in qto.
Felibian, in 1672, publilhed his Life, tranfiated from
the Italian of Agalio di Somma 5 but we cannot vouch
for the fidelity of the tranilation.
FIX.
P L A [ 593 1 P L A
Pix PIX. See MlNT-Marks.
i) PIZx\RRO, Francis, a celebrated Spar.ilh general,
I iRienta. ^ tjie (j]fcoverer ariC[ conqueror of Peru, in conjunction
with Diego Almagro, a Spanifh navigator. They are
both charged with horrid cruelties to the inhabitants ;
and they fell viftims to their own ambition, jeaiouly,
and avarice. Almagro revolting, was defeated and be¬
headed by Pizarro, who was affailinated by Almagro’s
friends in 1541- See Peru.
PLACE, locus, in Philofopluj, a mode of fpace or
that part of immoveable fpace which any body poffefl'es.
See Metaphysics, N° 185.
Place, in AJIronomij. The place of the fun, a ftar,
&c. denotes the fign and degree of the zodiac which
the luminary is in \ or the degree of the ecliptic, reck¬
oning from the beginning of Aries, which the planet’s or
liar’s circle of longitude cuts: and therefore coincides
wdth the longitude of the fun, planet, or liar. As the
line of the fun’s greatell declination 230 30' : to the fine
of any prefent declination given or obferved, for inllance,
230 15' : : fo is the radius 10 : to the fine of his longi¬
tude 8i° 52'} which, if the declination were north,
would give 200 52' of Gemini; if fouth, 20° 52' of
Capricorn, for the fun’s place. See Declination, &c.
The place of the moon being that part of her orbit
wherein Ihe is found at any time, is of various kinds,
by reafon of the great inequalities of the lunar motions,
which render a number of equations and redudlions ne-
ceffary before the juft point be found. The moon’s fic¬
titious place is her place once equated ; her place nearly
true, is her place twice equated} and her true place
thrice equated. See Astronomy, pajjim.
Place, in War, a general name for all kinds of for-
trelfes where a party may defend themfelves. Thus, 1.
A ftrong or fortified place is one flanked, and covered
wfith baftions. 2. A regular place, one whofe angles,
fides, baftions, and other parts, are equal j and this «•;
ufually denominated from the number of its angles, as a
pentagon, hexagon, &c. 3. Irregular place is one
whofe fides and angles are unequal.—4. Place of arms is
a ftrong city or town pitched upon for the chief maga¬
zine of an army ; or, in a city or garrifon, it is a large
open fpot of ground, ufually near the centre of the place
where the grand guard is commonly kept, and the gar¬
rifon holds its rendezvous at reviews, and in cafes of alarm
to receive orders from the governor. 3. Places of arms
of an attack, in a fiege, is a fpacious place covered from
the enemy by a parapet or epaulement, where the fol-
diers are polled ready to fuftain thofe at work in the
trenches againft the foldiers of the garrifon. 6. Place of
arms particular, in a garrifon, a place near every baf-
tion, wdiere the foldiers fent from the grand place to the
quarters afligned them relieve thofe that are either upon
the guard or in fight. 7. Place of arms without, is a
place allowed to the covert way for the planting of can¬
non, to oblige thofe who advance in their approaches to
retire. 8. Place of arms in a camp, a large place at the
head of the camp for the army to be ranged in and drawn
up in battalia. There is alfo a place for each particular
body, troop, or company, to afiemble in.
Common- Pl ACE. See COMMON-Place.
PLACENTA, in Anatomy and Midwifery, a foft
roundifh mafs, found in the womb of pregnant wmmen }
which, from its refemblance to the liver, was called by
the ancients hepar uterinum, uterine liver.
Vol. XVI. Part II.
PLACENTIA, called by the natives Piacenza, is Placentia,
a town cf Italy, and capital of a duchy of the fame Plagiary.
name, with a bilhop’s fee. It is feared about 100 paces
from the river Po, in a very fertile pleafant plain, wa¬
tered by a great number of rivulets, and furrounded
with hills, abounding in all forts of fruits. In its terri¬
tory there are falt-fprings, from which they make a very
white fait; and there are alfo mines of iron, -woods, and
warrens. It contains a great number of merchants, and
is reckoned three miles in circumference. Its fortifica¬
tions are incortfiderable, but the citadel is pretty ftrong.
The ftreets are ftraight, and the principal ftreet called
Stradone, is 25 common paces broad and 3000 feet
long, in a diretft line, with 600 ftone polls, for fepara-
ting the foot from the carriage-way, and on both fides
are 11 fpacious convents, 'i he. other buildings of the
city are not very remarkable, though it contains 49
churches, 28 convents, avid two aln.s-houfes. The ca¬
thedral is pretty much in the Gothic lafte j but the
church of the Auguftines is reckoned the moft beauti¬
ful, and efteemed worthy of its architedl, the celebra¬
ted Vignoli. The ducal palace, though large, makes
no great appearance externally; but within there are fome
good apartments. In the area before the town-houfc
ftand two admirable brafs ftatues of Alexander and Re-
natus IV. both of the houfe of Farnefe, and dukes of
Parma and Placentia. The biflrop is fuftragan to the
archbifliop of Milan. At this cky begins the Via Al-
milia, which extends as far as Rimini on the Adriatic.
The number of the inhabitants is about 30,000, among
whom there are 2000 ecclefiaftics. This city has been
taken feveral times in the wTars of Italy. The king of
Sardinia took poifeflion of it in 1 744, it being ceded to
him by the queen of Hungary ; but it was taken from
him in 1746, after a bloody battle. The French got
pofleflion of it in 1796. It has a famous univerfity,
and the inhabitants are much efteemed for their polite-
nefs. There is a great fair here every year on the 1 3th
of April, which is much frequented. Placentia is about
32 miles north-weft of Parma and 83 eaft of Turin. E.
Long. 10. 24. N. Lat. 43. 3.
PLAGIARY, in Philology, the purloining ano¬
ther man’s works, and putting them off as our owm.
Among the Romans, plagiarius was properly a perfon
who bought, fold, or retained a freeman for a flave 3 and
wras fo called, becaufe, by the Flavian law, fuch perfons
were condemned adplagas, 11 to be whipped.”
Thomafius has an exprefs treatife Dc plagio literario ;
wherein he lays down the laws and meafures of the
right which authors have to one another’s writings.—
“ Didlionary writers, at leaft fuch as meddle with arts
andfaiences (as is pertinently obferved by Mr Chambers),
feem exempted from the common laws of rneum and
tuum : they do not pretend to fet up on their owm bot¬
tom, nor to treat you at their own coft. Their works
are fuppofed, in great meafure, compofitions of other peo¬
ples ; and what they take from others, they do it avow^-
edly, and in the open fun.—In effedt, their quality gives
them a title to every thing that may be for their pur-
pofe, wherever they find it 3 and if they rob, they do not
do it any otherwife than as the bee does, for the public
fervice. Their occupation is not pillaging, but colledt-
ing contributions 3 and, if you alk them their authority,
they will produce you the praftice of their predeceffors
of all ages and nations.”
PLAGIUM,
P L A [
plagium, PLAGIUM, in Law. See Kidnapping.
, PLAGUE, Pestilence, or Pejlilential Fever, is a
* very acute, malignant, and contagious difeafe j being a
putrid fever of the word kind, and feldom failing to
prove mortal. Though it is generally defined a malig¬
nant fever, Diemerbrock thinks they ought to be diftin-
guilhed, fince the fever is not the effence of the difeafe,
but merely a fymptom or effeft of it. See Medicine,
n° 221.
The plague, as is generally agreed, is never bred or
propagated in Britain, but always imported from abroad,
efpecially from the Levant, Leffer Alia, Egypt, &c.
where it is very common. Sydenham has remarked
that it rarely infefts this country oftener than once in 40
years, and happily we have been free of it for a much
longer period.
Authors are not as yet agreed concerning the nature
of this dreadful diftemper. Some think that infedts
are the caufe of it, in the fame way that they are the
caufe of blights, being brought in fwarms from other
climates by the wind, when they are taken into the
lungs in refpiration ; the confequence of which is, that
they mix with the blood and juices, and attack and cor¬
rode the vifcera. Mr Boyle, on the other hand, thinks
it originates from the effluvia or exhalations breathed
into the atmofphere from noxious minerals, to which
may be added flagnant waters and putrid bodies of every
kind.
Mr Gibbon thinks that the plague is derived from
damp, hot, and ftagnating air, and the putrefaction of
animal fubftances, efpecially locufts. See Gibbon's Ro¬
man lii/lonj, 410 edit. vol. iv. p. 327—332, where there
is alfo a very particular account of the plague which
depopulated the earth in the time of the emperor Jufti-
nian.
The Mahometans believe that the plague proceeds
from certain fpirits, or goblins, armed with bows and
arrows, fent by God to puniffl men for their fins 5 and
that when the wounds are given by fpedtres of a black
colour, they certainly prove fatal, but not fo when the
arrows are fhot by thofe that appear white. They there¬
fore take no precaution to guard themfelves againft it.
The wifer profeflbrs of this religion, however, at prefent
a£t otherwife ; for we find a receipt recommended by
Sidy Mohammed Zerroke, one of the moft celebrated
Marabouts, prefaced with thefe remarkable words :
The lives of us all are in the hands of God, when it
is we muft die. However, it hath pleafed him to fave
many perfons from the plague, by taking every morn¬
ing while the infedlion rages, one pill or two of the fol¬
lowing compofition •, viz. of myrrh two parts, faffron
one part, of aloes two parts, of fyrup of myrtle berries,
y.yi” But this remedy is confined to the more enlighten¬
ed ; for the bigotry of the lower fort is fo extreme as
to make them defpife all precautions which people of
other nations ufe. Of this extreme and fooliffl preju¬
dice Dr Chandler gives an interefting account when (peak¬
ing of the plague at Smyrna. This learned author is of
opinion that the difeafe arifes from animalcules, which
594 1 P L A
he fuppofes to be invifible. See Chandler's Travels in Plague,
a Afia Minor, p. 279. &e. iy——v—
a It is a remarkable fadt, that plagues are fometimes
partial, and that they only attack particular animals, or
a particular defcription of perfons, avoiding others alto¬
gether, or attacking them but (lightly. Thus Ferne-
lius informs us of a plague, or murrain, in 1514, which
invaded only cats. Dionyfius Halicarnafieus mentions
a plague which attacked none but maids; and that
which raged in the time of Gentilis, killed fcarcely
any women, and very few but lufiy men. Boterus men¬
tions another plague, which aflaulted none but the
younger fort; and wtc have inftances of the fame kind
of a later (handing (a). Cardan fpeaks of a plague at
Bafil, w'ith wfflich the Switzers were infedhed, and the
Italians, Germans, or French, exempted: and John
Utenhovius takes notice of a dreadful one at Copenha-
g-.n, wfflich, though it raged among the Danes, fpared
the Germans, Dutch, and Engliffl, wfflo went wTith all
freedom, and without the Teaft danger, to the houfes of
the infedhed. During the plague wfflich ravaged Syria
in 1760, it was obferved that people of the founded
conftitutions w^ere the mod liable to it, and that the
weak and delicate were either fpared or eafily cured. It
w7as mod fatal to the Moors; and, when it attacked
them, it was generally incurable.
When the plague raged in Holland in 1636, a young
girl was feized with it, had three carbuncles, and wTas
removed to a garden, where her lover, wfflo was be¬
trothed to her, attended her as a nurfe, and dept with
her as his wife. He remained uninfefted, and (he re¬
covered, and wras married to him. The dory is related
by Vine. Fabricius in the Mifc. Cur. Ann. II. Obf.
188.
Many methods have been adopted in different coun¬
tries to prevent the importation of this dreadful fcourge
« f the human race, and to dop the progrefs of infec¬
tion after it has been imported. In England, mayors,
bailiffs, head officers of corporations, and judices of
peace, have power to tax inhabitants, houfes, and lands,
&c. within their precinfts, for the relief of perfons in-
fetded with the plague ; and judices of the county may
tax perfons wdthin five miles round, on a paridi’s ina¬
bility ^ the tax to be levied by didrefs and fale of goods,
or in default thereof by imprifonment. Infefted per¬
fons going abroad, after being commanded to keep
houfe for avoiding farther infeddions, may be redded by
watchmen, &c. qnd puniffled as vagrants, if they have
no fores upon them and if they have infe&ious fores
on them it is felony. Judices of the peace, &c. are to
appoint fearchers, examiners, and buriers of the dead,
in places infetded, and adminider oaths to them for the
performance of their duties, Szc.Jlat. 1 Jac. 1. cap. 31,
See Quarantine.
The commiffion at Mofcow having, in the year
1770, invented a fumigation-powffler, wfflich, from fe-
veral leffer experiments, had proved efficacious in pre¬
venting the infetdion of the plague j in order more
fully to afeertain its virtue in that refpeft, it wras de¬
termined.
(a) See the account of the yellow fever under the article Philadelphia, wfflere it appears that the difeafe was
fatal to fame forts of perfons than to others.
P L A [ S95 J P L A
Plague. ^ terrhined, towards the end of the year, that ten male-
v*——' factors under fentence of death fhould, without under¬
going any other precautions than the fumigations, be
confined three weeks in a lazaretto, be laid upon the
beds, and drefi'ed in the clothes, wThich had been ufed
by perfons fick, dying, and even dead, of the plague in
the hofpital. The experiment was accordingly tried,
and none of the ten malefaftors wrere then infe&ed, or
have been fince ill. The fumigation powder is prepared
as follows.
Powder of the frjlfre)igth.~\ Take leaves of juniper,
juniper-berries pounded, ears of wheat, guaiacum wood
pounded, of each fix pounds j common faltpetre pound¬
ed, eight pounds j fulphur pounded, fix pounds j Smyrna
tar, or myrrh, two pounds : mix all the above ingredi¬
ents together, wdiich will produce a pood of the pow der
of fumigation of the firfl ftrength. [yV. B. A pood is
40 pounds Ruffian, which are equal to 35 pounds and a
half or 36 pounds Englilh avoirdupoife.j
Powder of the fecond frength.~\ Take fouthern-
wrood cut into fmall pieces, four pounds y juniper ber¬
ries pounded, three pounds common faltpetre pound¬
ed, four pounds; fulphur pounded, two pounds and a
half j Smyrna tar, or myrrh, one pound and a half:
mix the above together, which will produce half a
pood of the powrder of fumigation of the fecond
ftrength.
Odoriferous powder.Take the root called ka/mus
cut into fmall pieces, three pounds; leaves of juniper
cut into fmall pieces four pounds ; frankincenfe pounded
grofsly, one pound j ftorax pounded, and rofe flowTers^
half a pound j yellow amber pounded, one pound 5 com¬
mon faltpetre pounded, one pouud and a half; fulphur,
a quarter of a pound : mix all the above together, which
will produce nine pounds and three quarters of the odo¬
riferous powder.
Remark on the powder of fumigation]. If guaiacum
cannot be had, the cones of pines or firs may be ufed in
its ftead; likewife common tar of pines and firs may be
ufed inftead of the Smyrna tar, or myrrh, and mugw'ort
may fupply the place of fouthernwood.
Thucydides, who wras himfelf infefted, lib. ii. gives
us an account of a dreadful plague which happened at
Athens about the year before Chrift 430, wrhile the
Peloponnefians under the command of Archidamus
wafted all her territory abroad 5 but of thefe two ene-
levere.
The moft dreadful plague that ever raged at Rome
wTas in the reign of Titus. A. D. 80. The emperor left
no remedy unattempted to abate the malignity of the di-
ftemper, a6ting during its continuance like a father to
his people. The fame fatal difeafe raged in all the pro¬
vinces of the Roman empire in the reign of M. Aurelius,
A. D. 167, and was followed by a dreadful famine, by
earthquakes, inundations, and other calamities. The
Romans believed that TEfculapius fometimes entered in¬
to a ferpent, and cured the plague.
About the year 430 the plague vifited,Britain, }uft
after the Pi<5ts and Scots had made a formidable im afion
of the fouthern part of tire ifiand. The plague raged
with uncommon fury, and fwept away molt of thofe whom
the fvvord and famine had fpared, lb that the living were
fcarcely fufficient to bury the dead.
About the year- 1348 the plague became abncft ge¬
neral over Europe. A great many authors give an ac- Prague,
count of this plague, which is faid to have appeared firit '-“—v'"”
in the kingdom of Kathay in the year 1346, and to
have proceeded gradually weftward to Conftantinople
and Egypt. From Conftantinople it palled into Greece,
Italy, France, and Africa, and by degrees along the
coafts of the ocean into Britain and Ireland, and after¬
wards into Germany, Hungary, Poland, Denmark and
the other northern kingdoms. According to Antoninus
archbiftrop of Florence the diftemper carried off 60,000
people in that city, among whom was the hiitorian John
Villani.
In the year 1656 the plague was brought from Sar¬
dinia to Naples, being ifttroduced into the city by a
tranfport wuth foldiers on board. It raged wuth excef-
five violence, carrying off in lefs than fix months
400,000 of the inhabitants. The diftemper was at firit
called by the phyficians a malignant fever j but one of
them affirming it to be peftilential, the viceroy, wTho
wras apprehenfive left fuch a report would occafion all
communication with Naples to be broke off, was offend¬
ed with this declaration, and ordered him to be impri-
foned. As a favour, however, he allowed him to return
and die in his owrn houfe. By this proceeding of the
viceroy, the diftemper being negledfted, made a moft ra¬
pid and furious progrefs, and filled the whole city with
confternation. The ftreets wrere crowded with confufed
proceflions, which ferved to fpread the infeblion through
all the quarters. The terror of the people increaled
their fuperftition ; and it being reported that a certain
nun had prophefied that the peftilence wrould ceafe upon
building a hermitage for her filler nuns upon the hill of
St Martin’s, the edifice wras immediately begun with
the moft ardent zeal. Perfons of the higheft quality
ftrove who fhould perform the meaneft offices ; fome
loading themfelves with beams, and others carrying baf-
kets full of lime and nails, while perfons of all ranks
ftripped themfelves of their moft valuable effects, which
they threwr into empty hogfheads placed in the ftreets
to receive the charitable contributions. Their violent
agitation, however, and the increafing heats, diffufed
the malady through the whole city, and the ftreets and
the flairs of the churches w'ere filled w ith the dead ; the
number of whom, for fome time of the month of July,
amounted daily to 15,000.
The viceroy now ufed all pofllble precautions to abate
the fury of the diftemper, and to prevent its fpreading to
the provinces. The infedlion, however, defolated the
whole kingdom, excepting the provinces of Otranto and
the Farther Calabria, and the cities of Gaeta, Sorrento,
Paolo, and Belvedere. The general calamity was in-
creafed in Naples by malecontents, wdto infinuated that
the diftemper had been defignedly introduced by the
Spaniards, and that there were people in difguife who
went through the city lowing poifoned duft. This idle
rumour enraged the populace, who began to infult the
Spanuh foldiers, and threaten a fedition •, fo that the
viceroy, to pacify the mob, caufed a criminal to be broke
upon the wheel, under pretence that he was a difperfer
of the duft. A violent and plentiful rain falling about
the middle of Auguft, the diftember began to abate ;
and on the eighth of December the phyficians made a
folemn declaration that the city was entirely free from
infe&ion.
Of the dreadful plague which raged at London in
4 F 2 the
P L A [ 59S ] P L A
the year 1665, the reader will find an account in the
article London, N° 21. In 1720 the city of Mar fellies
was vifited with this deftru&ive difeafe, brought in a
fliip from the Levant-, and in feven months, during
which time it continued, it carried off not lefs than
60,000 people. This defolation is not yet obliterated
from the minds of the inhabitants; fome furvivors re¬
mained alive but a few years ago to tranfmit a tradi¬
tional account of it to after ages. There are two fine
pictures, painted by Puget, reprefenting fome of the
horrid feenes of that time. “ They are (fays Lady
Craven) only too well executed. I law feveral dying
figures taking leave of their friends, and looking their
laft, anxious, kind, and wilhful prayers on their fick in¬
fants, that made the tears flow down my cheeks. I
was told the phyficians and noblemen who were aflift-
ing the fick and dying, were all portraits: I can eafily
conceive it; for in fome faces there is a look of reflec¬
tion and concern which could only be drawn from the
life.” ZeZ/mr, p. 34, 35. This fatal event has caufed
the larvs of quarantine to be very fl:ri£tly enforced in
the lazaretto here, which is an extenfive infulated
building.
The ravages of this difeafe have been dreadful wherever
It has made its appearance. On the firft arrival of the
Europeans at the ifland of Gran Canaria, it contained
14,000 fighting men, foon after which, two thirds of
the whole inhabitants fell a facrifice to the plague, which
had doubtlefs been introduced by their new vifitors.
The dertru£tion it has made in Turkey in Europe, and
particularly in Conftantinople, mult be known to every
reader ; and its fatal effe&s have been particularly
heightened there by that firm belief which prevails
among the people of predeftination, &c. as has been al¬
ready mentioned. It is generally brought into Euro¬
pean Turkey from Egypt} where it is very frequent,
efpecially at Grand CAIRO. To give even a lilt of all
the plagues which have defolated many flourifhing coun¬
tries, would extend this article beyond all bounds; and
minutely to deferibe them all, would be impoffible. For
the plague at Smyrna, we refer to Chandler’s Travels
as above. Refpefting that which raged in Syria in
1760, we refer to the Abbe Mariti’s Travels through
Cyprus, Syria, and Paleftine, vol. i. p. 278—296. This
plague was one of the moft malignant and fatal that
Syria ever experienced -, for it fcarcely made its ap¬
pearance in any part of the body when it carried off
the patient.
In addition to what the reader will find upon this
fubiect in the article Medicine, and the obfervations
which have now- been offered, w-e beg leave to flate the
fentiments of Berthier on this fubjeft, in his account of
Bonaparte’s expedition into Syria.
“At the time of our entry into Syria, (fays he) all
the towns were infected by the plague ; a malady which
ig-norance and barbarity render fo fatal in the eaft.
Thofe who are affected by it give themfelves up for
dead ; they are immediately abandoned by every body,
and are left to die, when they might have been faved by
medicine and attention.
“ Citizen Degenettes, principal phyfician to the ar¬
my, difplayed a courage and charafter which entitle
him to the national gratitude. When our foldiers wTere
attacked by the leaft fever, it was fuppofed that they
had caught the plague, and thefe maladies tvere con¬
founded.' The fever hofpitals wrere abandoned by the Plague,
officers of health and their attendants. Citizen Dege- -\~~
nettes repaired in perfon to the hofpilals, vilited all the
patients, felt the glandular fwellings, dreffed them, de¬
clared and maintained that the diftemper was not the
plague, but a malignant fever with glandular fwellings,
w-hich might eafily be cured by attention, and keeping
the patient’s mind eafy.”
The views of Degenettes in making this diftinftion
w-ere worthy of the higheff commendation ; but Dr
Mofcley maintains that this fever was actually the
plague. The phyfician, howrever, carried his courage
fo far, as to make two incifions, and to inoculate the
fuppurated matter from one of thefe buboes above his
breaft, and under his armpits, but w^as not affebted with
the malady. He thus ealed the minds of the foldiers,
the firfl: ftep to a cure 5 and, by his afliduity and con-
ftant attendance in the hofpitals, a number of men at¬
tacked with the plague w7ere cured. His example wras
followed by other officers of health. “ There are, fays
Dr Mofeley, annual or feafonal diforders, more or lels
fevere, in all countries j but the plague, and other
great depopulating epidemics, do not always obey the
feafons of the year. Like comets, their courfe is ec¬
centric. They have their revolutions; but from whence
they come, or whether they go after they have made
their revolution, no mortal can tell.
“ Difeafes originating in the atmofphere feize fome,
and pafs by others ; and abt exclufively on bodies gra¬
duated to receive their impreffions ; other wife whole na¬
tions would be deftroyed. In fome conllitutions of the
body the accefs is ealy, in fome difficult, and in others
impoffible.
“ The air of confined places may be fo vitiated as to
be unfit for the purpofes of the healthy exiftence of any
perfon. Hence gaol, hofpital, and fliip fevers. But, as
thefe diftempers are the offspring of a local caufe, that
local caufe, and not the diffempered people, communi¬
cate the difeafe.
“ The infection, were it not in the atmofphere, would
be confined within very narrow7 limits ; have a determi¬
nate fphere of ablion ; and none but phyficians and at¬
tendants on the fick w'ould fuffer ; and thefe muff fuf-
fer ; and the caufe and the effebts would be palpable to
our fenfes. Upon this ground, the precaution of quaran¬
tine ivould be rational. But who then would vifit and
attend the fick, or could live in hofpitals, prifons, and
lazarettos ?”
The author is convinced from thefe reafonings, that
the bubo and carbuncle, of which w-e hear fo much in
Turkey, and read fo much in our own hiftory of plagues,
arife from heating food and improper treatment; that
they contain no infebtion ; and confequently that they
are not the natural depofit of the morbific virus feparated
from the contagion.
Speaking of the plague, Mr Brown fays, “ the firfl:
fymptoms are faid to be thirft ; 2. Cephalagia ; 3- A
ftiff and uneafy fenfation, with rednefs and tumour about
the eyes; 4. Watering of the eyes; 5. White puftules
on the tongue. Not uncommonly, all thefe have fuc-
ceffively ftiown themfelves, yet the patient has recover¬
ed ; in wffiich cafe, wffiere fuppuration has had place,
the fldn always remains difcoloured, commonly of a
purple hue. Many who have been bled in an early
ftage of the diforder, have recovered without any fatal
fymptoms y
Plague
Plan.
P L A t 591 1 FLA
fymptoms 5 but whether from that or any other caufe,
does not appear certain.”
Oil rubbed into the flun affs as a preventive, as
well as a cure of the plague. When the operation is
performed to prevent infection, it is iuccefsfully per¬
formed with that view at Smyrna, as'often as the plague
makes its appearance in the city. As it is not done for
the purpcfe of promoting peripiration, it is not requi-
fite that it fhould be performed with the fame fpetd as
when for curing the diforder; nor is it neceifary to ab-
llain from tieih, and to ufe foups 5 but it will be proper
-to ufe only fowls or veal for fome days, without any
feafoning. It will in fine be neceflfary to guard againit
indigefiible food, and fuch liquors as might put in mo¬
tion or inflame the mafs of the blood.
This interetling difcovery merits the attention of all
medical men 5 for if olive oil has been found efficacious
in curing or preferving againit one fpecies of infeftion,
it is not abfurd to fuppofe. that the fame or other kinds
of oil might be productive of mucb benefit in other ma¬
lignant infectious difeafes. We hope foon to hear of
fome trial being made with it in this country. Would
it be of any fervice in the yellow fever, fo prevalent in
the weftern world ?
PLAIN, or Plane, in general, an appellation given
to whatever is fmooth and even, or fimple, obvious,
and eafy to be underftood; and, confequently, Hands
oppofed to rough, enriched, or laboured.
A plain figure, in geometry, is an uniform furface ;
from every point of whofe perimeter right lines may
be drawn to every other point in the fame.
A plain angle is one contained under two lines, or
furfaces, in contradiftinCtion to a folid angle. See
Angle under Geometry.
The doctrine of plain triangles, as thofe included un¬
der three right lines, is termed />/ain trigonometry. See
the article Trigonometry.
PLAIN Chart. See the article Chart.
PLAIN-Sailing. See Navigation.
PLAISE, the Englifh name of a fpecies of pleuro-
nedtes. See Pleuronectes, Ichthyology Index.
PLAN, in general, denotes the reprefentation of
fomething drawn on a plane ; fuch are maps, charts,
ichnographies, &c. See Map, Chart, &c.
The term plan, however, is particularly ufed for a
draught of a building, fuch as it appears, or is intended
to appear, on the ground, fhowing the extent, divifion,
and diftribution of its area or ground-plot into apart¬
ments, rooms, paffages, &c.
A geometrical plan is that wherein the folid and
vacant parts are reprefented in their natural propor¬
tions.
The raifed plan of a building is the fame with what
is otherwife called an elevation or orthography. See Or.-
THOGRAPHY.
A perfpeClive plan is that exhibited by degradations
or diminutions, according to the rules of perfpeftive.
See Perspective.
To render plans intelligible, it is ufual to diftinguifh
the maffives with a black wralh \ the projeCtures on the
ground are drawn in full lines, and thofe fuppofed over
them in dotted lines. The augmentations or alterations
to be made are diftinguifhed by a colour different from
what is already built \ and the tints of each plan made
lighter as the ftories are raifed.
In large buildings it is ufual to have three feveral
plans for the three firft ftories.
PL ANGUS, Francis, dodlor of phyfic, was born
at Amiens in 1696, and died on the 19th of September
1765, aged 69 years. Fie is the author of fome works
which have had confiderable reputation. 1. A complete
Syiiem of Surgery, in 2 vols in 12mo} a treatife much
recommended by lurgeons to their pupils. 2. A choice
Library of Medicine, taken from periodical publications,
both French and others : this curious colleflion, con¬
tinued and completed by M. Goulin, makes 9 vols in
4to, or 18 vols in i2mo. 3. A Tranllation of Vander
Wiel’s Obfervations on Medicine and Surgery, 1758,
2 vols in 1 2mo. Plancus was alio the editor of various
editions of works on medicine and furgery, which he
enriched with notes.
PLANE, in Geometry, denotes a plain furface, or
one that lies evenly between its bounding lines: and as
a right line is the ftiorteft extenfion from one point to
another, fo a plane iurface is the ftiorteft extenfion
from one line to another.
In aftronomy, conics, &c. the term plane is frequent¬
ly uled for an imaginary furface, fuppofed to cut and
pafs through folid bodies j and on this foundation is
the whole doftrine of conic feclions built. See Astro¬
nomy, Conic Setdions, &e.
In mechanics, planes are either horizontal, that is,
parallel to the horizon, or inclined thereto. See Me¬
chanics.
The determining how far any given plane deviates
from an horizontal line, makes the whole bufinefs of
levelling. See the article Levelling.
In optics, the planes of refle&ion and refra&ion are
thofe drawn through the incident and reflefted or re¬
fracted rays. See Optics.
In perfpeiffive we meet with the perfpedtive plane,
which is fuppofed to be pellucid, and perpendicular to
the horizon; the horizontal plane, fuppofed to p»fs
through the fpectator’s eye, parallel to the horizon j
the geometrical plane, likewife parallel to the horizon,
wherein the object to be reprefented is fuppofed to be
placed, &c. See Perspective.
The plane of projection in the ftereographic projec¬
tion of the fphere, is that on which the projection is
made, correfponding to the perfpeCtive plane. See Pro¬
jection.
Plane, in joinery, an edged tool or inftrument for
paring and thaving of wood fmooth. It conlifts of a
piece of wood very fmooth at bottom, as a ftock or
lhaft; in the midft of which is an aperture, through
which a fteel edge, or chiffel, placed obliquely, paffes;
which, being very fharp, takes off the inequalities of
the wood along which it Hides.
PLANE-Tree, in Botany. See Platanus.
PLANET, a celeftial body, revolving round the fun
as a centre, and continually changing its pofition with
refpeft to the fixed ftars 5 whence the name planet,
which is a Greek word, fignifying “ wanderer.”
The planets are ufually diftinguiihed into primary
and fecondary. The primary ones, called by way of
eminence planets, are thofe which revolve round tkhe
fun as a centre j and the fecondary planets, more ufually
called fatellites or moons, are thofe which revolve round
a primary planet as a centre, and conftantly attend it
in its revolution round the fun.
The
t
P L A [ 598 ] P L A
Planet The primary planets are again diftinguiihed into fu-
1 II perior and inferior. The fuperior planets are thofe far-
r J'3n‘' ther from the fun than our earth j as Mars, Jupiter, Sa¬
turn, and the Georgium Sidus •, and the inferior planets
are thofe nearer the fun than our earth, as Venus and
♦ Mercury. For an account of the planets lately difcover-
ed, fee Vesta.
That the planets are opaque bodies, like our earth,
is thought probable for the following reafons. 1. Since
in Venus, Mercury, and Mars, only that part of the
dilk illuminated by the fun is found to fhine ; and
again, Venus and Mercury, when between the earth
and the fun, appear like dark fpots or maculae on the
fun’s difk} it is evident, that Mars, Venus, and Mer¬
cury, are opaque bodies, illuminated with the borrowed
light of the fun. And the fame appears of Jupiter,
from its being void of light in that part to which the
fhadow of the fatellites reaches, as well as in that part
turned from the fun ; and that his fatellites are opaque,
and refleft the fun’s light, is abundantly drown. Again,
fince Saturn, with his ring and fatellites, only yield a
faint light, fainter coniiderably than that of the fixed
liars, though thefe be vaftly more remote, and than that
of the reft of the planets j it is paft doubt that he too
with his attendants are opaque bodies. 2. Since the
fun’s light is not tranfmitted through Mercury and Ve¬
nus, when placed againft him, it is plain they are denfe
opaque bodies *, which is likewife evident of Jupiter,
from his hiding the fatellites in his fhadow j and there¬
fore, by analogy, the fame may be concluded of Sa¬
turn. 3. From the variable fpots of Venus, Mars, and
Jupiter, it is evident thefe planets have a changeable
atmofphere ; which changeable atmofphere may, by a
like argument, be inferred of the fatellites of Juniter;
and therefore, by fimilitude, the fame may be concluded
of the other planets. 4. In like manner, from the moun¬
tains obferved in Venus, the fame may be fuppofed in
the other planets. 5. Since, then, Saturn, Jupiter, and
the fatellites of both, Mars, Venus, and Mercury, are
opaque bodies ftrining with the fun’s borrowed light, are
furnilhed with mountains, and encompaffed with a
changeable atmofphere ; they have, it is concluded, wa¬
ters, feas, &c. as well as dry land, and are bodies like
the moon, and therefore like the earth. And hence it
leems allb highly probable, that the other planets have
their animal inhabitants as vrell as our earth.
PLANETARIUM, an aftronomical machine, fo
called from its reprefenting the motions, orbits, &c. of
the planets, agreeable to the Copernican lyftem. See
Astronomy.
PLANETARY, fomething that relates to the pla¬
nets. Hence we fay, planetary worlds, planetary inha¬
bitants, &c. See Planet.
Planetar T System, is the fyftem or affemblage of
the planets, primary and fecondary, moving is their re-
fpe&ive orbits, round their common centre the fun. See
Astronomy.
PLANET ART Days.—Among the ancients, the week
was fhared among the feven planets, each planet having
its day. This we learn from Dion Caftius and Plutarch,
Sympof. 1. 4. q. 7. Herodotus adds, that it was the
Egyptians who firft difcovered what god, that is, what
planet, prefides over each day $ for that among this peo¬
ple the planets were diredfors. And hence it is, that in
moft European languages the days of the week are ftill Planetary
denominated from the planets: Sundav, Mondav, &c. H
See Week. * , F!^nt-
PLANET ART Years, the periods of time in which
the feveral planets make their revolutions round the fui>
or earth.—As from the proper revolution of the fan, the
folar year takes its original 5 fo from the proper revolu¬
tions of the reft of the planets about the earth, fo many
forts of years do arife, viz. the Saturnian year, which is
defined by 29 Egyptian years, 1 74 hours, 58 minutes,
equivalent in a round number to 30 folar years. The
Jovial year, containing 317 days, 14 hours, 59 minutes.
—The Martial year, containing 321 days, 23 hours,
31 minutes. For Venus and Mercury, as their years,
when judged of with regard to the earth, are almoft
equal to the folar year; they are more ufually eftimated
from the fun, the true centre of their motions : in
which cafe, the former is equal to 224 days, 16 hours,
40 minutes j the latter to 87 days, 23 hours, 14 mi¬
nutes.
PLANIMETRY, that part of geometry which con-
fiders lines and plain figures, without confidering their
height or depth, See Geometry.
PLANISPHERE, fignifies a jmoje&ion of the
fphere, and its various circles on a plane j in which
fenfe, maps, whereon are exhibited the meridians and
other circles of the fphere, are planifpheres. See Map.
PLANT is defined to be an organical body, defti-
tute of fenfe and fpontaneous motion, adhering to an¬
other body in fuch a manner as to draw from it its nou-
rilhment, and having a power of propagating itfelf by
feeds.
The vegetation and economy of plants is one of thofe
fubjecls in which our knowledge is extremely circum-
fcribed. A total inattention to the ftrudture and eco¬
nomy of plants is the chief reafon of the fmall progrefs
that has been made in the principles of vegetation, and
of the inftability and flu&uation of our theories con¬
cerning it 5 for which reafon we (hall give a ftiort de-
fcription of the ftru&ure of plants, beginning with the
feed, and tracing its progrefs and evolution to a ftate of
maturity.
I. Of Seeds.~] The feeds of plants are of various fi¬
gures and fizes. Moft of them are divided into two
lobes •, though fome, as thofe of the crefs-kind, have fix j
and others, as the grains of corn, are not divided, but
entire.
But as the effential properties of all feeds are the fame,
when confidered with regard to the principles of vege¬
tation, our particular deicriptions fhall be limited to one
feed, viz. the great garden-bean. Neither is the choice
of this feed altogether arbitrary ; for, after it begins
to vegetate, its parts are more conipicuous than many
others, and confequently better calculated for inveftiga-
tion.
This feed is covered with two coats or membranes.
The outer coat is extremely thin, and full of pores; but
may be eafily feparated from the inner one (which is
much thicker), after the bean has been boiled, or lain a
few days in the foil. At the thick end of the bean there
is a fmall hole vifible to the naked eye, immediately
over the radicle or future root, that it may have a free
pafiage into the foil (fig. 1. A). When thefe coats are
taken off, the body of the feed appears, which is divid-
Kate
CCCGXX,
4
P L A [ 5
ed into two fmooth portions or lobes, lire fmoothnefs
of the lobes is owing to a thin film or cuticle with which
they are covered.
At the bafis of the bean is placed the radicle or future
root (fig. 3. A). The trunk of the radicle, juft as it
enters into the body of the feed, divides into two capi¬
tal branches, one of which is inferted into each lobe,
and fends off fmaller ones in all direftions through the
whole iubftance of the lobes (fig. 4. AA). Thefe ra¬
mifications become fo extiemely minute towards the
edges of the lobes, that they require the fineft glaffes to
render them vifible. To thefe ramifications Grew and
Malpighi have given the name offeminal root; becaufe,
by means of it, the radicle and plume, before they are
expanded, derive their principal nourifhment.
The plume, bud, or germ (fig. 3.), is inclofed in two
fmall correfponding cavities in each lobe. Its colour
and confiftence is much the fame with thofe of the ra¬
dicle, of which it is only a continuation, but having a
<}uite contrary direftion 5 for the radicle defcends into
the earth, and divides into a great number of fmaller
branches or filaments •, but the plume afcends into the
open air, and unfolds itfelf into all the beautiful variety
of ftem, branches, leaves, flower, fruit, &c. The plume
in corn fhoots from the fmaller end of the grain, and
amongft maltfters goes by the name of acrofpire.
The next thing to be taken notice of is the fubftance
or parenchymatous part of the lobes. This is not a mere
concreted juice, but is curioully organized, and confifts
of a vaft number of fmall bladders refembling thofe in
the pith of trees (fig. 5.).
Befides the coats, cuticle, and parenchymatous parts,
there is a fubftance perfectly diftinft from thefe, diftri-
buted in different proportions through the radicle, plume,
and lobes. This inner fubftance appears very plainly in
a tranfverfe feftion of the radicle or plume. Towards
the extremity of the radicle it is one entire trunk ; but
higher up it divides into three branches ; the middle
one runs direftly up to the plume, and the other two
pafs into the lobes on each fide, and fpread out into a
great variety of fmall branches through the whole bo¬
dy of the lobes (fig. 4.'). This fubftance is very properly
termed the feminal root: for when the feed is fown, the
moifture is firft abforbed by the outer coats, which are
everywhere furnifhed with fap and air-veffels; from thefe
it is conveyed to the cuticle •, from the cuticle it pro¬
ceeds to the pulpy part of the lobes j wTen it has got
thus far, it is taken up by the mouths of the fmall bran¬
ches of the feminal root, and paffes from one branch in¬
to another, till it is all collefled into the main trunk,
which communicates both with the plumei and radicle,
the two principal involved organs of the future plant.
After this the fap or vegetable food runs in twaa oppo-
fite dire&ions : part of it afcends into the plume, and
promotes the growth and expanfion of that organ 5 and
part of it defcends into the radicle, for nourilhing and
evolving the root and its various filaments. Thus the
plume and radicle continue their progrefs in oppofite di-
reftions till the plant arrives at maturity.
It is here wTorth remarking, that every plant is really
pofieffed of two roots, both of which are contained in
the feed. The plume and radicle, wdien the feed is firft
depofited in the earth, derive their nourifhment from the
feminal root ; but, afterwards, wdren the radicle begins
to ftioot out its filaments, and to abforb fome moifture,
9 ] P L A
not, however, in a fufficient quantity to fupply the ex¬
igencies of the plume, the tw o lobes, or main body of
the feed, rife along with the plume, affume the appear¬
ance of twro leaves, refembling the lobes of the feed in
fize and fhape, but having no refemblance to thofe of the
plume, for which reafon they have got the name of dif
Jinular leaves.
I hefe diftimilar leaves defend the young plume from
the injuries of the weather, and at the lame time, by
abforbing dewq air, &c. affift the tender radicle in nou-
nftnng the plume, with which they have ftill a connec¬
tion by means of the feminal root above deferibed. But
when the radicle or fecond root has defeended deep
enough into the earth, and has acquired a fufficient num¬
ber of filaments or branches for abforbing as much ali¬
ment as is proper for the growth of the plume 5 then the
feminal or diflimilar leaves, their utility being entirely
fuperfeded, begin to decay and fall off.
Fig. 1. A, the foramen or hole in the bean through
which the radicle Ihoots into the foil.
Fig. 2. A tranfverfe feftion of the bean ; the dots
being the branches of the feminal root.
3’ radicle. B, the plume or bud.
Fig. 4. A view of the feminal root branched out up¬
on the lobes.
Fig. 5. A longitudinal fe&ion of one of the lobes
of the bean a little magnified, to (how the fmall bladders
of which the pulpy or parenchymatous part is compo-
fed.
Figs. 6. 7. A, a tranfverfe fedlion of the radicle. B,
a tranfverfe fection of the plume, ftiowing the organs or
veffels of the feminal root.
Fig. 8. The appearance of the radicle, plume, and fe¬
minal root, w'hen a little further advanced in growth.
Haying thus briefly deferibed the feed, and traced its
evolution into three principal organic parts, viz. the
plume, radicle, and feminal leaves, we fhall next take
an anatomical view of the root, trunk, leaves, &c.
2. Of the root.] In examining the root of plants,
the firft thing that prefents itfelf is the fldn, which is of
various colours in different plants. Every root, after
it has arrived at a certain age, has a double Ikin. The
firft is coeval with the other parts, and exifts in the feed:
but afterwards there is a ring fent off from the bark,
and forms a fecond fkin ; e. g. in the root of the dande--
lion, towards the end of May, the original or outer fkin
appears fhrivelled, and is eafily feparated from the new-
one, wThich is frefher, and adheres more firmly to the
bark. Perennial plants are fupplied in this manner
with a new fkin every year; the outer one always falls
off in the autumn and winter, and a new' one is formed
from the bark in the fucceeding fpring. The fkin has
numerous cells or veffels, and is a continuation of the
parenchymatous part of the radicle. However, it does
not confift folely of parenchyma ; for the microfcope
fhows that there are many tubular ligneous veffels inter-
fperfed through it.
When the fkin is removed, the true cortical fubftance
or bark appears, which is alio a continuation of the pa¬
renchymatous part of the radicle, but greatly augment¬
ed. The bark is of very different fizes. In moft trees
it is exceeding thin in proportion to the wood and pith.
On the other hand, in carrots, it is almoft one-half of
the femidiameter .of the root 5 and, in dandelion, it is
nearly twice as thick as the woody part.
Plant.
Plate
CCCCXX.
The
FLA r 600 1 P L A
The bark is compofed of two fubftances; the paren¬
chyma or pulp, which is the principal part, and a few
•woody fibres. The parenchyma is exceedingly porous,
and has a great refemblance to a fponge 3 for it Ihrivels
confiderably when dried, and dilates to its former di-
menfions when infuied in water. Thefe pores or vef-
fels are not pervious, fo as to communicate with each
-other ; but confift of diflincl little cells or bladders,
fcarcely vifible without the afliftance of the microfcope.
In all roots, thefe cells are conftahtly filled- with a thin
watery liquor. They are generally of a fpherical figure ;
though in fome roots, as the buglofs and dandelion, they
are oblong. In many roots, as the horft-radifh, peony,
afparagus, potato, &c. the parenchyma is of one uni¬
form ftru&ure. But in others it is more diverfified,
and puts on the lhape of rays, running from the centre
towards the circumference of the bark. Thefe rays
fometimes run quite through, the bark, as in lovage;
and fometimes advance towards the middle of it, as in
melilot and moft of the leguminous and umbelliferous
plants. Thefe rays generally Hand at an equal diftance
from each other in the fame plant; but the diitance va¬
ries greatly in different plants. Neither are they of
equal fizes : in carrot they are exceedingly fmall, and
fcarcely difcernible ; in melilot and chervil, they are
thicker. They are likewife more numerous in fome
plants than in others. Sometimes they are of the fame
thicknefs-from one edge of the bark to the other ; and
fome grow wider as they approach to the fkin. The
velfels with which thefe rays are amply furnifked, are
fuppofed to be air-veflels, becaufe they are always found
to be dry, and not fo tranfparent as the veffels which
evidently contain the fap.
In all roots there are ligneous vefiels difperfed in dif¬
ferent proportions through the parenchyma of the bark.
Thefe ligneous veffels run longitudinally through the
bark in the form of fmall threads, which are tubular, as
is evident from the rifing of the fap in them when a root
is cut tranfverfely. Thefe ligneous fap-veifels do not
run in dire& lines through the bark, but at fmall dif-
tances incline towards one another, in fuch a manner that
they appear to the naked eye to be inofculated ; but the
microfcope difcovers them to be only contiguous, and
braced together by the parenchyma. Thefe braces or
coar&ations are very various both in fize and number in
different roots ; but in all plants they are moft numerous
towards the inner edge of the bark. Neither are thefe
veffels fingle tubes 3 but, like the nerves in animals, are
bundles of 20 or 30 fmall contiguous cylindrical tubes,
which uniformly run from the extremity of the root,
without fending off any branches or fuffering any chahge
in their fize or ftiape.
In fome roots, as parfnep, efpecially in the ring next
the inner extremity of the bark, thefe veffels contain a
kind of lymph, which is fweeter than the fap contained
in the bladders of tire parenchyma. From this circum-
ftance they have got the name of lymph-duBs.
Thefe lymph-dufts fometimes yield a mucilaginous
lymph, as in the comfrey 3 and fometimes a white
milky glutinous lymph, as in the angelica, fonchus, bur¬
dock, fcorzonera, dandelion,-&c. The lymph-dufts are
fuppofed to be the veffels from which the gums and bal-
fams are fecerned. The lymph of fennel, when expofed
to the air, becomes a clear tranfparent balfam 3 and
that of the fcdrzonera, dandelion, &c. condenfes into a Plant,
gum. , ' »—
The fituation of the veffels is various. . In fome plants
they ftand in a ring or circle at the inner edge of the
bark, as in afparagus 3 in others, they appear in lines or
rays, as in borage 3 in the parfnep, and feveral other
plants, they are moft confpicuous towards the outer edge
of the bark ; and in the dandelion, they are difpofed in
the form of concentric circles.
The wood of roots is that part which appears after the
bark is taken off, and is firmer and lefs porous than the
bark or pith. It confifts of two diftindh fubftances, viz.
the pulpy or parenchymatous, and the ligneous. The
wood is conned!ed to the bark by large portions of the
bark inferted into it. Thele infertions are moftly in the
form of rays, tending to the centre of the pith, which
are eafily difcernible by the eye in a tranfverfe fedlion of
moft roots. Thefe infertions, like the bark, confift of
many veffels, moftly of a round or oval figure.
The ligneous veffels are generally difpoied in collate¬
ral rows running longitudinally through the root. Some
of thefe contain air, and others fap. The air-vejfels are
fo called, becaufe they contain no liquor. Thefe air-
veffels are diftinguifhed by being whiter than the others,
The pith is the centrical part of the root. Some roots
have no pith, as the ftramonium, nicotiana, &c. 3 others
have little or none at the extremities of the roots, but
have a confiderable quantity of it near the top. The
pith, like every other part of a plant, is derived from
the feed 3 but in fome it is more immediately derived
from the bark : for the iirfewtions of the bark running in
■betwixt the rays of the wood,' meet in the centre, and
conftilute the pith. It is owing to this circumftance,
that, among roots which have no pith in their lower
parts, they are amply provided with it towards the top,
as in columbine, lovage, &c.
The bladders of the pith are of very different fizes, and
generally of a circular figure. Their pofition is more
uniform than in the bark. Their fides are not mere
films, but a compofition of fmall fibres or threads 3 which
gives the! pith, when viewed with a microfcope, the ap¬
pearance of a piece of fine gauze or net-work.
We fliall conclude the defcription of roots with ob-
ferving, that their wrhole fubftance is nothing but a con¬
geries of tubes and fibres, adapted by nature for the ab-
forption of nouriftiment, and of courfe the extenfion and
augmentation of their parts.
Fig. 9. A tranfverfe fedlion of the root of wmrm-
wrood as it appears to the naked eye.
Fig. 10. A fedlion of fig. 9. magnified. AA, the
Ikin, with i^s veffels. BBBB, the bark. The round
holes CCC, &c. are the lymph-dudls of the bark : All
the other holes are little cells and fap-veffels. DDD,
parenchymatous infertions from the bark, with the cells,
&c. EEEE, the rays of the wood, in which the holes
are the air-veffels. N. B. This root has no pith.
3. Of the Trunk, Stalk, or Stem.~\ In defcribing the
trunks of plants, it is neceffary to premife, that what¬
ever is faid with regard to them applies equally to the
branches.
The trunk, like the root, confifts of three parts, viz.
the bark, wood, and pith. Thefe pnris, though fub-
ftantially the fame in the trunk as in the root, are in
many cafes very different in their texture and appearance.
The
*
v W/Jir//«// /f r//^ t/rtr/ftforfeort •
r Xj a x t s.
Plate ('CC(' XX11 .
i
a lit.
Y—“
P L A [ 601 ] P L A
Tiie £vln of the bark is compofed of very minute
bladders, interfpei-fed with longitudinal woody fibres,
as in the nettle, thiftle, and mott herbs. The outfide
of the Ikin is vifibly porous in fome plants, particularly
the cane.
The principal body of the bark is compofed of pulp
or parenchyma, and innumerable vefiels much larger
than thofe of the Ikin. The texture of the pulpy part,
though the fame fublfance with the parenchyma in
roots, yet feldom appears in the form of rays running to¬
wards the pith ; and when thefe rays do appear, they
do not extend above half-way to the circumference.
The vefiels of the bark are very differently fituated, and
deftined for various purpofes in different plants. For ex¬
ample, in the bark of the pine, the innermoft are lymph-
duefs, and exceedingly fmall ; the outermoft are gum or
refmiferous veflels, defined for the fecretion of turpen¬
tine and are fo large as to be diftindtly vifible to the
naked eye.
The wood lies between the bark and pith, and confifts
of two parts, viz. a parenchymatous and a ligneous. In
all trees, the parenchymatous part of the wood, though
much diverfified as to fize and, confiftence, is uniformly
difpofed in diametrical rays, or infertions running be¬
twixt fimilar rays of the ligneous part.
The true rvood is nothing but a congeries of old dried
lymph-duifts. Between the bark and the wood a new
ring of thefe duds is formed every year, which gradu¬
ally lofes its foftnefs as the cold fealbn approaches, and
towards the middle of winter is condenfed into a folid
ring of wood. Thefe annual rings, which are diltindly
vifible in molt trees rvhen cut through, lerve as natural
marks to diltinguilh their age (fig. 11.12.). The rings of
one year are fometimes larger, fometimes lefs, than thofe
of another, probably owing to the favourablenefs or un-
favourablenefs of the feafon.
The pith, though of a different texture, is exadly of
the fame fubflance with the parenchyma of the bark, and
the infertions of the wood. The quantity of pith is va¬
rious in different plants. Inflead of being increafed eve¬
ry year like the wood, it is annually diminifhed, its vef-
fels drying up, and affuming the appearance and ftruc-
ture of wood ; infomuch that in old trees there is fcarce
inch a thing as pith to be difeerned.
A ring of fap-veifels is ufually placed at the outer
edge of the pith, next the wood. In the pine, fig, and
walnut, they are very large. The parenchyma of the
pith is compofed of fmall cells or bladders, of the fame
kind with thofe of the bark, only of a larger fize. The
general figure of thefe bladders is circular; though in
fome plants, as the thiftle and borage, they are angu¬
lar. Though the pith is originally one conne&ed chain
of bladders, yet as the plant grows old they fhrivel, and
open in different direftions. In the walnut, after a cer¬
tain age, it appears in the form of a regular tranfverfe
hollow divifion. In fome plants it is altogether want¬
ing ; in others, as the fonchus, nettle, &c. there is only
a tranfverfe partition of it at every joint. Many other
varieties might be mentioned but thefe muft be left to
the obfervation of the reader.
Fig. 11. A tranfve’-fe feftion of a branch of afh, as it
appears to the eye.
Fig. 12. The fame feflion magnified. AA, the
bark. BBB, an arched ring of fap-veflels next the
Jkin. CCC, the parenchyma of the bark with its cells,
Vol. XVI. Part II.
and another arched ring of fap-veffels. DD, a circular
line of lymph-ducf s immediately below the above arched
ring. EE, the wood. F, the firft year’s growth. G,
the fecond. H, the third year’s growth. Ill, the true
wTood. KK, the great air-veffels. LL, the leffer ones.
MMM, the parenchymatous infertions of the bark re-
prefented by the white rays. NO, the pith, with its
bladders or cells.
4. Of the Leaves.^ The leaves of plants confift of
the fame fubftance with that of the trunk. They are
full of nerves or woody portions, running in all direc¬
tions, and branching out into innumerable fmall threads,
interwoven with the parenchyma like fine lace or
gauze.
I he Ikin of the leaf, like that of an animal, is full of
pores, which both ferve for perfpiration and for the ab-
forption of dews, air, &c. Thefe pores or orifices differ
both in fhape and magnitude in different plants, which is
the caufe of that variety of texture or grain peculiar to
every plant.
The pulpy or parenchymatous part confifts of very
minute fibres, wound up into fmall cells or bladders.
Thefe cells are of various fizes in the fame leaf.
All leaves, of whatever figure, have a marginal fibre,
by which all the reft are bounded. The particular ftiape
of this fibre determines the figure of the leaf.
1 he veffels of leaves have the appearance of inofeu-
lating ; but, when examined by the microfeope, they
are found only to be interwoven or laid along each
other.
Plant.
What are called air-veffe/s, or thofe which carry no
fap, are vifible even to the naked eye in fome leaves.
When a leaf is flowly broken, they appear like fmall
woolly fibres, connected to both ends of the broken
pieC<:- Plate
Flg* I3- The appearance of the air-veffels to the eye, CCCuXXL
in a vine-leaf drawn gently afunder.
Fig. 14. A fmall piece cut off that leaf.
Fig’ 15* The fame piece magnified, in which the vef¬
fels have the appearance of a ferew.
Fig. 16. The appearance of thefe veffcls as they exift
in the leaf before they are ftretched out.
5. Of the Flower.It is needlefs here to mention
any thing of the texture, or oftheveffels, &c. of dowers,
as they are pretty fimilar to thofe of the leaf. It would
be foreign to our prefent purpofe to take any notice of
the characters and diftimffions of flowers. Thefe be¬
long to the fcience of Botany, to which the reader is
referred.
There is one curious fact, however, which muft not
be omitted, viz. T1 at every flower is perfe&ly formed
in its parts many months before it appears outwardly ;
that is, the flowers which appear this year are not pro¬
perly fpeaking the flowers of this year, but of the laft.
For example, mezereon generally flowers in January ;
but thefe flowers were completely formed in the month
of Auguft preceding. Of this faft any one may fatisfy
himfelf by feparating the coats of a tulip root about the
beginning of September 5 and he will find that the two
innermoft; form a kind of cell, in the centre of which
Hands the young flower, which is not to make its ap¬
pearance till the following April or May. Fig. 18. ex¬
hibits a view of the tulip-root when differed in Septem¬
ber, with the young flower towards the bottom.
6. Of the Fruit.] In deferibing the ftrufture of fruits,
4^ a
P L A [ 602 ] P L A
a few examples fhall be taken from fuch as are moft ge¬
nerally known.
A pear, befides the fkin, which is a production of the
ikin of the bark, confiits of a double parenchyma or pulp,
fap, and air-veffels, calculary and acetary.
The outer parenchyma is the fame fubftance continu¬
ed from the bark, only its bladders are larger and more
fucculent.
It is everywhere interfperfed with fmall globules or
grains, and the bladders refpeft thefe grains as a kind of
centres, every grain being the centre of a number of
bladders. The lap and air-veffels in this pulp are ex¬
tremely fmall.
Next the core is the inner pulp or parenchyma, which
confifts of bladders of the fame kind with the outer, only
larger and more oblong, correfponding to thofe of the
pulp, from which it feems to be derived. This inner
pulp is much fourer than the other, and has none of the
fmall grains interfperfed through it 5 and hence it has
got the name of acetary.
Between the acetary and outer pulp, the globules or
grains begin to grow larger, and gradually unite into a
hard llony bodyfefpecially towards the corculum or flool
of the fruit ; and from this circumftance it has been call¬
ed the calculary.
Thefe grains are not derived from any of the organi-
cal parts of the tree; but feem rather to be a kind of
concretions precipitated from the fap, limilar to the pre¬
cipitation from wine, urine, and other liquors.
The core is a roundilh cavity in the centre of the pear,
lined with a hard woody membrane, in which the feed
is inclofed. At the bottom of the core there is a fmall
duft or canal, which runs up to the top of the pear j
this canal allows the air to get into the core, for the
purpofe of drying and ripening the feeds.
Fig. 18. a tranfverfe feftion of a pear, as it appears
to the naked eye. A, the fkin, and a ring of fap-vefc
fels. B, the outer parenchyma, or pulp, with its vef-
fels, and ligneous fibres interfperfed. C, the inner pa¬
renchyma, or acetary, with its veffels, which are larger
than the outer one. D, the core and feeds.
Fig. 19. a piece cut off, fig. 19.
Fig. 20. is fig. 19. magnified. AAA, the fmall
grains or globules, with the veffels radiated from them.
Fig. 21. a longitudinal feftion of the pear, fhowing
a different view of the fame parts with thofe of fig. 18.
A the channel, or duft, which runs from the top of the
pear to the bottom of the core.
In a lemon, the parenchyma appears in three different
forms. The parenchyma of the rind is of a coarfe tex¬
ture, being compofed of thick fibres, woven into large
bladders. Thofe neareft the furface contain the effen-
tial oil of the fruit, which burfts into a flame when the
fkin is fqueezed over a candle. From this outmoft pa¬
renchyma nine or ten infertions or lamellae are produ¬
ced, which run between as many portions of the pulp,
and unite into one body in the centre of the fruit, which
correfponds to the pith in trunks or roots At the bot¬
tom and top of the lemon, this pith evidently joins with
the rind, without the intervention of any lamellae. This
circumftance fhows, that the pith and bark are aflually
conne£led in the trunk and roots of plants, though it is
difficult to demonftrate the connection, on account of the
clofenefs of their texture, and the minutenefs of their
fibres. Many veffels are difperfed through the whole of
this parenchyma \ but the largeft ones Hand on the in- Planfe.
ner edge of the rind, and the outer edge of the pith, juft
at the two extremities of each lamella.
The fecond kind of parenchyma is placed between
the rind and the pith j is divided into diftinft bodies
by the lamellae j and each of thefe bodies forms a large
bag-
Thefe bags contain a third parenchyma, which is
a clufter of linaller bags, diftinft and unconnefted with
each other, having a fmall llalk by which they are fixed
to the large bag. Within each of thefe fmall bags are
many hundreds of bladders, compofed of extremely mi¬
nute fibres. Thefe bladders contain the acid juice of the
lemon.
Fig. 22, a longitudinal fedlion of a lemon. AAA,
the rind with the veffels which contain the effential oil.
B B, the fubftance correfponding to the pith, formed
by the union of the lamellae or infertions. C C, its
continuation and connexion with the rind, independent
of the infertions.
Fig. 23. a tranfverfe fe&ion of the lemon. B B B,
&c. the nine pulpy bags, or fecond parenchyma, placed
between the rind and the pith 5 and the clufter of fmall
bags, which contain the acid juice, inclofed in the large
ones. C C, the large veffels that furround the pith.
D D, two of the large bags laid open, {bowing the
feeds, and their conneftion with the lamellae or mem¬
branes which form the large bags.
Of the Perfpiration of PLANTS, and the quantity of
moi/lure daily imbibed by them.—Thefe curious particulars
have been determined with great accuracy by Dr Hales.
The method he took to accomplifh his purpofe was as
follows.—In the month of July, commonly the warmeft
feafon of the year, he took a large fun-flower three feet
and an half high, which bad been purpofely planted in
a flower-pot when young. He covered the pot with
thin milled lead, leaving only a fmall hole to preferve a
communication with the external air, and another by
which he might occafionally fupply the plant with wa¬
ter. Into the former he inferted a glafs tube nine inches
long, and another {hotter tube into the hole by which he
poured in the w^ater; and the latter was kept clofe flop¬
ped with a cork, except when there was occafion to ufe
it. The holes in the bottom of the pot were alfo flopped
up with corks, and all the crevices {hut with cement.—
Things being thus prepared, the pot and plant were
weighed for x 5 feveral days 5 after which the plant was
cut off clofe to the leaden plate, and the ftump wrell co*
vered with cement. By weighing, he found that there
perfpired through the unglazed porous pot two ounces
every 12 hours ; which being allowed for in the daily
weighing of the plant and pot, the greateft perfpiration,
in a warm day, w^as found to be one pound 14 ounces $
the middle rate of perfpiration, one pound four ounces ;
the perfpiration of a dry warm night, without any fen-
fible dew, was about three ounces j but wffien there wras
any fenfible though fmall dew, the perfpiration was no¬
thing ; and when there was a large dewr, or fome little
rain in the night, the plant and pot was increafed in
weight twyo or three ounces.
In order to know what quantity was perfpired from a
fquare inch of furface, our author cut off all the leaves
of the plant, and laid them in five feveral parcels, ac¬
cording to their feveral fizes ; and then meafured the fur¬
face of a leaf of each parcel, by laying over it a large
lattice
P L A [
Plant, lattice made with threads, in which each of the little
Y——' fquares was ^ of an inch j by numbering of which, he
had the furface of the leaves in fquare inches ; which,
multiplied by the number of leaves in the correlponding
parcels, gave the area of all the leaves. By this method
he found the furface of the whole plant above ground to
be 5616 fquare inches, or 39 fquare feet. He dug up
another fun-flower of nearly the fame fize, which had
eight main roots, reaching 15 inches deep and fidewife,
from the ftem. It had befides a very thick buflr of la¬
teral roots from the eight main roots, extending every
way in a hemifphere about nine inches from the ftem
and main roots. In order to eftimate the length of all
the roots, he took one of the main roots with its laterals,
and meafured and weighed them j and then weighed the
other feven with their laterals j by which means he
found the fum of all their lengths to be 1448 feet.
Suppofing then the periphery of thefe roots at a medium
to be O.131 of an inch, then their furface will be 2276
fquare inches, or 15.8 fquare feet *, that is, equal to 0.4
of the furface of the plant above ground. From calcula¬
tions drawn from thefe obfervations, it appears, that a
fquare inch of the upper furface of this plant perfpires
part of an inch in a day and a night j and that a
fquare inch of the furface underground imbibed of
an inch in the fame time.
The quantity perfpired by different plants, however,
is by no means equal. A vine-leaf perfpires only T
of an inch in 1 2 hours a cabbage perfpires ¥V of an
inch in the fame time •, an apple-tree in 12 hours j
and a lemon in 12 hours.
Of the circulation of the Sap in PLANTS.—Concerning
this there have been great difputes *, fome maintaining,
that the vegetable fap has a circulation analogous to the
blood of animals j while others affirm, that it only af-
cends in the day-time, and defcends again in the night.
In favour of the do&rine of circulation it has been urged,
that upon making a tranfverfe incifton into the trunk of
a tree, the juice which runs out proceeds in greater quan¬
tity from the upper than the lower part *, and the fwel-
ling in the upper lip is alfo much greater than in the
lower. It appears, however, that when two fimilar in-
cifions are made, one near the top and the other near
the root, the latter expends much more fap than the
former. Hence it is concluded, that the juice afcends
by one fet of veflels and defcends by another. But, in
order to (how this clearly, it would be neceffary firft to
prove that there is in plants, as in animals, fome kind
of centre from which the circulation begins, and to
which it return s j but no fuch centre has been difcovered
by any naturalift $ neither is there the leaft proviflon ap¬
parently made by nature whereby the fap might be pre¬
vented from defcending in the very fame veffels through
which it afcends. In the la£feal veflels of animals,
which we may fuppofe to be analogous to the roots of
vegetables, there are valves which effe&ually prevent
the chyle when once abforbed from returning into the
inteftincs 5 but no fuch thing is obferved in the veflels of
vegetables ; whence it muft be very probable, that when
the propelling force ceafes, the juice defcends by the
very fame veflels through which it afcended.—This
matter, however, has been cleared up almoft as well as
the nature of the fubjeft will admit of by the experiments
Hales f. Thefe experiments are fo numerous, that
i.p. 142. 'f°r a particular account of them we muft refer to the
603 ] P L A
work itfelf j however, his reafoning againft the circula¬
tion of the fap will be fuffkiently intelligible without
them. “ We fee (fays he), in many of the foregoing ex¬
periments, what quantities of moifture trees daily imbibe
and perfpire : now the celerity of the lap muft be very
great, if that quantity of moifture muft, moft of it, af-
cend to the top of the tree, then defcend, and afcend
again, before it is carried off by perlpuation.
“ The defeft of a circulation in vegetables feems in
fome rneafure to be fupplied by the much greater quan¬
tity of liquor, which the vegetable takes in, than the
animal, whereby its motion is accelerated j for we find
the fun-flower, bulk for bulk, imbibes and perfpires 17
times more frelh liquor than a man, every 24 hours.
“ Befides, Nature’s great aim in vegetables being only’
that the vegetable life be carried on and maintained, there
was no occafion to give its fap the rapid motion which
wTas neceffary for the blood of animals.
“ In animals, it is the heart which fets the blood in
motion, and makes it continually circulate } but in ve¬
getables we can difcover no other caufe of the fap’s mo¬
tion but the ftrong attraction of the capillary fap-veffels,
aflifted by the brilk undulations and vibrations caufed by
the fun’s warmth, whereby the fap is carried up to the
top of the talleft trees, and is there perfpired off through
the leaves : but when the furface of the tree is grea;Ly
diminilhed by the lofs of its leaves, then alfo the perfpi-
ration and motion of the fap is proportionably diminilh¬
ed, as is plain from many of the foregoing experiments :
fo that the afcending velocity of the fap is principally
accelerated by the plentiful perfpiration of the leaves,
thereby making room for the fine capillary veflels to
exert their vaftly attracting power, which perfpiration is
effeCted -by the brilk rarefying vibrations of warmth j a
power that does not feem to be any ways well adapted
to make the fap defcend from the tops of vegetables by
different veflels to the root.
“ If the fap circulated, it muft needs have been feen de¬
fcending from the upper part of large gaflies cut in bran¬
ches fet in water, and with columns of water prefling on
their bottoms in long glafs tubes. In both which cafes
it is certain that great quantities of water pafled through
the ftem, fo that it muft needs have been feen defcending,
if the return of the fap downwards were by trufion or pul-
fion, whereby the blood in animals is returned through the
veins to the heart j and that pulfion if there were any, muft
neceffarily be exerted with prodigious force, to be able to
drive the fap through the finer capillaries. So that, if
there be a return of the fap downwards, it muft: be by at -
traftion, and that a very powerful one, as we may fee by
many of thefe experiments. But it is hard to conceive
what and where that power is which can be equivalent
to that provifion nature has made for the afcent of the fap
in confequence of the great perfpiration of the leaves.
“ The inftances of the jeffamine-tree, and of the paf-
fion-tree, have been looked upon as ftrong proofs of the
circulation of the fap, becaufe their branches, which
were far below the inoculated bud, wrere gilded : but we
have many vifible proofs in the vine, and other bleeding
trees, of the fap’s receding back, ar pulhing forwards
alternately, at .different times of the day and night. And
there is great reafon to think that the fap of all other
trees, has fuch an alternate, receding, and progreflive
motion, occafioned by the altemacies of day and night,
warm and cool, moift and dry.
A G 2 “ tor
Plant.
FLA [604] PL A
“ For the fap in all vegetables does probably recede
in fome meafure bcm the tops ol the branches, as the
bun leaves them •, becaufe its rarefying power then
ceafing, the greatly rarefied fap, and air mixed with it,
will condenfe, and take up lefs room than they did, and
the dew and rain will then t>e itrongly imbibed by the
leaves 5 whereoy the body and branches oi the vegetable
which have been much exhauited oy the great evapora¬
tion of the day, may at night imbibe fap and dew
from the leaves } for by ieveral experiments, plants w’ere
found to increafe coniiderably in weight, in dewy and
moilt nights. And by other experiments on the vine,
it was found that the trunk and branches of vines were
always in an imbibing date, caufed by the great perlpi-
ration of the leaves, except in the bleeding leafon ; but
when at night that perfpiring power ceafes, then the con¬
trary imbibing power will prevail, and draw the fap and
dew from the leaves, as well as moitture from the roots.
“ And we have a tarther proof of this by fixing mer¬
curial gages to the ffems of feveral trees which do not
bleed, whereby it is found that they are always in a
itrongly imbibing date, by drawing up the mercury fe¬
veral inches : whence it is eafy to conceive, how fome
of the particles of the gilded bud in the inoculated jef-
famine may be abforbed by it, and thereby communicate
their gilding miafma to the fap of other branches} efpe-
eially when, fome months after the inoculation, the dock
of the inoculated jeffamine is cut off- a little above the
bud ; w'hereby the dock, which was the counterabling
part to the dem, being taken aw7ay, the dem attrafb
more vigoroufiy from the bud.
“ Another argument for the circulation of the fap is,
that fome forts of the grads will infebt and canker the
docks they are grafted on : but by mercurial gages
fixed to frefh-cut Hems of trees, it is evident that thofe
dems were in a drongly imbibing date } and confe-
qently the cankered docks might very likely draw fap
from the graff, as well as the graff alternately from
the dock *, jud in the fame manner as leaves and
branches do from each other, in the viciflitudes of day
and night. And this imbibing powTer of the dock is
fo great, wdiere only fome of the branches of a tree
are grafted, that the remaining branches of the dock
will, by their drong attraction, darve thofe graffs } for
which reafon it is ufual to cut off the greated part of
the branches of the dock, leaving only a few fmall ones
to drawr up the fap.
“ The indance of the ilex grafted upon the Englilh
oak, feems to afford a very confiderable argument
againd a circulation. For, if there were a free uni¬
form circulation of the fap through the oak and ilex,
why (hould the leaves of the oak fall in winter, and not
thofe of the ilex ?
“ Another argument againd an uniform circulation
of the lap in trees, as in animals, may be drawn from an
experiment, where it wTas found by the three mercurial
gages fixed'to the fame vine, that while fome of its
branches changed their date of protruding fap into a
date of imbibing, others continued protruding fap j one
nine, and the other thirteen days longer.”
To this reafoning of Dr Hales we {hall fubjoin an ex¬
periment made by Mr Muitel of the Academy of Scien¬
ces at Rouen, which feems decifive againd the doftrine
of circulation. His account of it is as follows.—“ On
the t2th of January I placed feveral flirubs in pots
againd the windows of my hot-houfe, fome vvitlnn the Plant,
houfe and others without it. Through holes made for
this purpofe in the panes of giafs, 1 paii'ed a branch of
each of the dirubs, fo that thofe in the infide had a
branch without, and thole on the outiide one with¬
in ; after this, I took care that the holes diould be ex-
adfly clofed and luted. This inverfe experiment, I
thought, if followed clolely, could not fail affording fuf-
ficient points of companion, to trace out the differences,
by the obfrrvation of the effebis.
“ The 20th of January, a week after this difpolition,
all the branches that were in the hot-houle began to dif-
cloie their buds. In the beginning of February there ap¬
peared leaves j and towards the end of it, Ihoots of a
confiderable length, which prefented the young flowers.
A dw7arf apple-tree, and feveral role-trees, ceing fubmit-
ted to the lame experiment, diowedthe fame appearance
then as they commonly put on in May •, in Ihort, all the
branches which were within the hot-houfe, and conlc-
quently kept in the warm air, were green at the end of
February, and had their thoots in great fomardnefs. Very
different were thofe parts of the fame tree which were
without and expofed to the cold. None of thefe gave
the leail fign of vegetation •, and the frolt, which was in-
tenfe at that time, broke a role-pot placed on the outfide,
and killed fome of the branches of that v. ry tree which,
on the infide, was every day putting forth more and more
Ihoots, leaves, and buds, lb that it was in full vegetation
on one fide, whilft frozen on the other.
“ The continuance of the froft occafioned no change
in any of the internal branches. They all continued m
a very brilk and verdant ftate, as if they did not belong
to the tree which, on the outfide, appeared in the ffate
of the greatell fuffering. On the 15th of March, not-
withftanding the feverity of the fealon, all was in full
bloom. The apple-tree had its root, its Hem, and part
of its branches, in the hot-houfe. Thefe branches were,
covered with leaves and flowers ; but the branches of
the fame tree, which were carried on the outfide, and
expofed to the cold air, did not in the leaft partake of
the adlivity of the reft, but were abfolutely in the lame
ftate wdiich all trees are in during winter. A rofe-tree,
in the fame pofition, fhowed long Ihoots with leaves and
buds j it had even {hot a vigorous branch upon its
ftalk j whilft a branch which palled through to the
outfide had not begun to produce any thing, but was
in the fame ftate with other rofe-trees left in the
ground. This branch is four lines in diameter, and
18 inches high.
“ The rofe-tree on the outfide was in the fame ftate ;
but one of its branches drawn through to the infide of
the hot-houfe was covered with leaves and rofe-buds.
It was not without aftonilhment that I faw this branch
fhoot as brilkly as the rofe-tree which wras in the hot-
hoifle, whofe roots and ftalk, expofed as they wrere to
the warm air, ought, it Ihould feem, to have made it
get forwarder than a branch belonging to a tree, whofe
roots, trunk, and all its other branches, were at the very ’
time froft-nipped. Notwfithftanding this, the branch
did not feem affedled by the ftate of its trunk j but the
adlion of the heat upon it produced the fame effebl as
if the whole tree had been in the hot-houfe.” Memcires
Of the Perpendicularity of PLANTS.—This is a curi-^ /’
ous phenomenon in natural hiftory, which was firft ob- Royal des
ferved by M. Dodart, and publifhed in an effay on the Sciences.
affb£lationan‘ I^"S'
P L A [ 605 T P L A
Plant. affe&ation of perpendicularity obferved in the ftems or
* v ltalk.s of all plants, in the roots of many, and even in
their branches, as much as poffible. Though almolt all
plants rife a little crooked, yet the Items ihoot up per¬
pendicularly, and the roots-link down perpendicularly :
even thofe, wyhich by the declivity of the foil come out
inclined, or thole which are diverted out of the perpen¬
dicular by any violent means, again redrefs and itraight-
en themfelves and recover their perpendicularity, by
making a fecond and contrary bend or elbow without
rectifying the firft. We commonly look upon this af¬
fectation without any furprife ; but the naturalilt who
knows what a plant is, and how it is formed, finds it a
fubje£t of aftonilhment.
Each feed we know contains in it a little plant, al¬
ready formed, and needing nothing but to be unfolded 5
the little plant has its root; and the pulp, which is ufu-
ally feparated into two lobes, is the foundation of the
firfl food it draws by its root when it begins to germi¬
nate. If a feed in the earth therefore be difpofed fo as
that the root of the little plant be turned downwards,,
and the item upwards, and even perpendicularly up¬
wards, it is eafy to conceive that the little plant coming
to unfold itfelf, its ftalk and root need only follow' the
direction they have to grow perpendicularly*. But \ve
know that the feeds of plants, whether fown of them-
telves or by man, fall in the ground at random ; and
among the great variety of fituations with regard to the
ftalk of th eir plant, the perpendicular one upwards is
but one. In all the reft, therefore, it is neceflary that
the ftalk rectify itfelf, fo as to get out of the ground :
but what force effects this change, which is unqueftion-
ably a violent adion ?- Does the ftalk find a lefs load of
earth above it, and therefore go naturally that w*ay
w'here it finds the leaft obftacle ? Were this fo, the lit¬
tle root, w'hen it happens to be-uppermoft, muft alfo fol¬
low* that direction, mid mount up.
To account for two fuch different adions, M. Dodart
fuppofes that the fibres of the ftalks are of fuch a nature.
as to be contraded and ftiortened by the heat of the fun,
and lengthened out by the moiiture of the earth ; and,
on the contrary, that the fibres of the roots are contrad¬
ed by the moifture of the earth, and lengthened by the
heat of the fun. When the plantule therefore is invert¬
ed, and the root at the top, the fibres which compofe
«ne of the branches of the root aie not alike expofed to
the moifture of the earth, the low*er part being mere ex¬
pofed than the upper. The lower muft of courfe con-
trad the molt ; and this *contradion is again promoted
by the lengthening of the upper, whereon the fun ads
with the greateft force. This branch of the root muft
therefore recoil towards the earth, and, infmuating
through the pores thereof, muft get underneath the bulb,
&c. By inverting this reafoning we difeover how* the
ftalk comes to get uppermoft.
We fuppofe then that the earth attrads the root to it¬
felf, and that the fun contributes to its defeent ; and, on
the other hand, that the fun attrads the ftem, and the
earth contributes to fend it towards the fame. With re-
fped to the rtraightening of the ftalks in the open air,
our author imagines that it arifes from the impreflion of
external caufes, particularly the fun and rain. For the
upper part of a ftalk that is bent is more expofed to the
rain, dew*, and even the fun, &.c. than the under; and
thefe caufesj in a certain ftrudure of the fibres, both
equally tend to ftraighten the part moft expofed by the * Pfai
Ihortening they iucceillveiy occaiion in it 3 for moifture ~~v
Ihortens by fw*elling and heat by dithpating. What that
ftrudtire is which gives the fibres iuch different qualities,
or whereon it depends, is a myitery as yet beyond our
depth.
M. de la Hire accounts for the perpendicularity of the
ftems or ftalks ot plants in this manner : he fuppoles that
the root of plants draws a coarler and heavier juice, and
the ftem and branches a finer and more vo atile one.
Moft naturalifts indeed conceive the root to be the fto-
mach o* the plant, v/here the juices of the earth are iub-
tilized to as- to become able to rife through the ftem to
the extremity of the branches. This difference of juices
fuppofes larger pores in the roots than the it a Ik, &c.
and, in a word, a different contexture. This difference
muft; be found even in the little invifible plant inclofed
in the ieed: in it, therefore, we may conceive 3 point
of ieparation ; fuch as, that all on one fide, for example
the root, fhall be unfolded by the gfoffcr juices, and all
on the other tide by the more fubtile ones. Suppofe the
plantule, when its parts begin to unfold, to be entirely
inverted, the root at the.top, and the ftalk below*; the
juices entering the root will be coarfeit, and when they
have opened and enlarged the pores fo as to admit juices
of a determinate weight, thofe juices prefling the root
more and more w*ill drive it downwards j and this will
increafe as the root is more extended or enlarged : for
tlje point of feparation being conceived as the fixed point
of a lever, they will act by the longer arm. The vola¬
tile juices at the fame time having penetrated the ilaik,
will give it a direction from below upwards; and, by
reafon of the lever, will give it more and more every
day. The little plant is thus turned on its fixed point
of feparation till it become perfedtly erect.
WThen the plant is thus erected, the ftalk Ihould ftill
rife perpendicularly, in order to give it the more firm
biding, and enable it to withftand the effort of wind and
w*eather. M. Parent thus accounts for this effect: If
the nutritious juice which arrived at the extremicy of a
rifing ftalk evaporate, the weight of the air which en-
compaiTes it on all fides w*ill make it afeend vertically :
but if, inftead of evaporating, it congeal, and lemain
fixed to that extremity whence it was ready to yo
the weight of the air wilt give it the fame -n recue
that the ftalk will have acquired a fmall new part vc
cally laid over it, juft as the flame in a candle helu
any way obliquely to the horizon ftill continues verti¬
cal by the preiTure of the atmoiphere. The new drops
of juice that fucceed will follow the fame direction 5 and
as all together form the ftalk, that muft of courfe be
vertical, unlefs fome particular circumftance intervene.
The branches, which are at firft fuppofed to proceed
laterally out of the Itaik in the firlf embryo of the plant,
though they fnould even come out in an horizontal di-
redlion, muft alfo raife themfelves upwards by the con-
ftant direction of the nutritious juice, which at firft
fcarcely meets any refiftance in a tender fupple branch j
and afterwards, even though the branch grow more
firm, it will a£t with the more advantage 5 fince the
branch, being become longer, furniflies it with a longer
arm or lever. The (lender adtion of even a little drop
becomes very confiderable by its continuity, and by the-
afliftance of finch circumftances. Hence may we ac¬
count for that regular fituation and diredUon of the.
branches.
P L A [ 606 ] P L A
Plant, branches, fince they all make nearly the fame conftant
—  1 angle of 450 with the item, and with one another.
M. Attruc accounts for the perpendicularity of the
items, and their redrefling themfelves, thus : 1. He
thinks the nutritious juice arifes from the circumference
of the plant, and terminates in the pith : And, 2. That
fluids, contained in tubes either parallel or oblique to
the horizon, gravitate on the lower part of the tubes,
and not at all on the upper. Hence it follows, that, in a
plant placed either obliquely or parallel to the horizon,
the nutritious juice will aft more on the lower part of
the canals than on the upper j and by this means they
will infinuate more into the canals communicating there¬
with, and be collefted more copioufly therein: thus
the parts on the lower fide will receive more accretion
and be more nourhhed than thofe on the upper, the ex¬
tremity of the plant will therefore be obliged to bend
upwards.
This principle brings the feed into its due fituation at
firft. In a bean planted upfide down, the plume and
radicle may be feen with the naked eye (hooting at firft
direftly for about an inch 5 after which they begin to
bend, the one downward, and the other upward. The
fame is the cafe in a heap of barley to be made into
malt, or in a quantity of acorns laid to fprout in a moift
place, &c. Each grain of barley and each acorn has a
different fituation j and yet every fprout tends direftly
upw'ard, and every root dowmvard, and the curvity or
bend they make is greater or lefs as their fituation ap¬
proaches more or lefs to the direftion wherein no curva¬
ture at all would be neceffary. But two fuch oppofite
motions cannot poffibly arife without fuppofing fome dif¬
ference between the twTo parts : the only one w7e know
of is, that the plume is fed by a juice imported to it by
tubes parallel to its fides, whereas the radicle imbibes
its nourifhment at every pore in its furface. When the
plume therefore is either parallel or inclined to the hori¬
zon, the nutritious juice, feeding the lower parts more
than the upper, will determine its extremes to turn up¬
ward, for the reafons before given. On the contrary,
when the radicle is in the like fituation, the nutritious
juice penetrating through the upper part more copioufly
than through the under, there will be a greater accre¬
tion of the former than of the latter 5 and the radicle
will therefore be bent downwards, and this mutual c»r-
vity of the plume and radicle muff continue till fuch
time as their fides are nourifhed alike, which cannot be
till they are perpendicular.
Of the Food of PLANTS.—This hath been fo fully dif-
cuffed under the article Agriculture, that little re¬
mains to be faid upon the fubjeft in this place. The
method of making dephlogifticated or vital air de novo,
is now fo much improved, that numberlefs experiments
may be made with it both on animals and vegetables.
It appears, indeed, that thefe tvro parts of the creation
are a kind of counterbalance to one another •, and the
noxious parts or excrements of the one prove falutary
food to the other. Thus, from the animal body conti¬
nually pafs •ff certain effluvia, svhich vitiate or phlogif-
ticate the air. Nothing can be more prejudicial to ani¬
mal life than an accumulation of thefe effluvia : on the
other hand, nothing is more favourable to vegetables
than thofe excrementitious effluvia of animals •, and ac¬
cordingly they greedily abforb them from the earth, or
from the air. With refpeft to the excrementitious parts
4
of living vegetables, the cafe is reverfed. The pure ft Plant,
air is the common effluvium which paffes ©ff from vege- '' ""**
tables $ and this, however favourable to animal life, is
by no means fo to vegetable \ whence we have an addi¬
tional proof of the doftrine concerning the food of plants
delivered under the article Agriculture.
With regard to the effefts of other kinds of air on
vegetation, a difference of fome confequence took place
between Dr Prieftley and Dr Percival. The former, in
the firft volume of his Experiments and Obfervations on
Air, had afferted that fixed air is fatal to vegetable as
well as to animal life. This opinion, hovrever, wTas op-
pofed by Dr Percival, and the contrary one adopted by
Dr Hunter of York in the Georgical Effays, vol. v.
The experiments related by thefe two gentlemen would
indeed have been decifive, had they been made with fuf-
ficient accuracy. That this w7as the cafe, however, Dr
Prieftley denies j and in the 3d volume of his Treatife
on Air has fully detefted the miftakes in Dr Percival’s
Experiments j rvhich proceeded in faft from his having
ufed, not fixed air, but common air mixed with a fmall
quantity of fixed air. His experiments, when repeated
with the pureft fixed air, and in the moft careful man¬
ner, were always attended tvith the fame effeft, name¬
ly, the killing of the plant.
It had alfo been afferted by Drs Percival and Hunter,
that w7ater impregnated with fixed air w7as more favour¬
able to vegetation than fimple water. This opinion was
likewife examined by Dr Prieftley : however, his expe¬
riments were indecifive 5 but feem rather unfavourable
to the ufe of fixed air than otherwife.
Another very remarkable faft with regard to the food
of plants has been difcovered by Dr Prieftley •, namely,
that fome of them, fuch as the willow7, comfrey, and
duckweed, are nouriflied by inflammable air. The firft:,
he fays, flouriftres in this fpecies of air fo remarkably,
that, “ it may be faid to feed upon it with great avidity. pricJticy oh
This procefs terminates in the change of what remains Air, vol. t.
of the inflammable air into phlogifticated air, and fome- P- *•
times into a fpecies of air as good as common air, or even
better j fo that it muft be the inflammable principle in
the air that the plant lakes, converting it, no doubt, in¬
to its proper nouriftiment.”
What the followers of Stahl call phlogifticated air
and inflammable air, are fo clofely allied to each other,
that it is no wronder they fliould ferve promifcuoufly for
the food of plants. The reafon w7hy both are not agree¬
able to all kinds of plants, moft probably is the different
quantity of phlogiftic matter contained in them, and the
different aftion of the latent fire they contain ; for all
plants do not require an equal quantity of nouriftunent j
and fuch as require but little, will be deftroyed by hav¬
ing too much. The aftion of heat alfo is effentially ne¬
ceffary to vegetation 5 and it is probable that very much
of this principle is abforbed from the air by vegetables.
But if the air by which plants are partly nouriffled con¬
tains too much of that principle, it is very probable that
they may be deftroyed from this caufe as well as the
other ; and thus inflammable air, which contains a vaft
quantity of that aftive principle, may deftroy fuch plants
as grow in a dry foil, though it preferves thofe which
grow7 in a wret one. See Vegetation.
Diffcmination of Plants.—So great are the prolife
powers of the vegetable kingdom, that a Angle plant al-
moft of any kind, if left to itfelf, would, in a (hort time,
overrun
P L A [ 607 ] P L A
Plant, overrun the whole world. Indeed, fuppofing the plant
"■"V to have been only a lingle annual, with two feeds, it
would, in 20 years, produce more than a million of its
own fpecies what numbers then mull have been produ¬
ced by a plant whofe feeds are fo numerous as many of
thofe with which we are acquainted ? In that part of our
work we have given particular examples of the very pro¬
lific nature of plants, which we need not repeat here •,
and we have made fome obfervations on the means by
which they are carried to diftant places. This is a very
curious matter of fa£t, and as fuch we fliall now give a
fuller account of it.
If nature had appointed no means for the fcattering of
thefe numerous feeds, but allowed them to fall down in
the place where they grew, the young vegetables muft
of neceflity have choked one another as they grew up,
and not a Angle plant could have arrived at perfe&ion.
But fo many ways are there appointed for the diffemina-
tion of plants, that we fee they not only do not hinder
each others growth, but a fingle plant will in a fhort
time fpread through different countries. The moft evi¬
dent means for this purpofe are,
1. The force of the air.—That the efficacy of this
may be the greater, nature has raifed the feeds of vege¬
tables upon ftalks, fo that the wind has thus an oppor¬
tunity of a&ing upon them with the greater advantage.
The feed-capfules alfo open at the apex, left the ripe
feeds fhould drop out without being widely difperfed by
the wind. Others are furniffied with wings, and a pap-
pous down, by which,'after they come to maturity, they
are carried up into the air, and have been known to fly
the diftance of 50 miles : 138 genera are found to have
winged feeds.
2. In fome plants the feed-veffels open wdth violence
when the feeds are ripe, and thus throw them to a con-
fiderable diftance •, and we have an enumeration of 50
genera whofe feeds are thus difperfed.
3. Other feeds are furniffied with hooks, by which,
when ripe, they adhere to the coats of animals, and are
cafried by them to their lodging places. Linnaeus rec¬
kons 50 genera armed in this manner.
4. Many feeds are difperfed by means of birds and
other animals ; who pick up the berries, and afterwards
eje«ft the feeds uninjured. Thus the fox dilTeminates the
privet, and man many fpecies of fruit. The plants found
growing upon walls and houfes, on the tops of high
rocks, &c. are moftly brought there by birds ; and it is
imiverfally known, that by manuring a field with new
dung, innumerable weeds will fpring up which did not
exift there before: 193 fpecies are reckoned up which
may be diflfeminated in this manner.
5. The growth of other feeds is promoted by animals
in a different way. While fome are eaten, others are
icattered and trodden into the ground by them. The
fquirrel gnaws the cones of the pine, and many of the
feeds fall out. When the loxia eats off their bark, al-
moft his only food, many of their feeds are committed
to the earth, or mixed in the morafs with mofs, where
he had retired. The glandularia, when ffie hides up
her nuts, often forgets them, and they ftrike root. The
fame is obfervable of the walnut ; mice collect and bury
great quantities of them, and being afterwards killed by
different animals, the nuts germinate.
6. We are aftoniffied to find moffes, fungi, byffus,
sr.d mucor, growing everywhere} but it is for want of
refle&ing that their feeds are fo minute that they are Plant:
almoft invifible to the naked eye. They float in the air '-"“‘v--
like atoms, and are dropped everywhere, but grow only
in thefe places wdiere there was no vegetation before $
and hence we find the fame moffes in North America
and in Europe.
7. Seeds are alfo difperfed by the ocean, and by ri¬
vers. “ In Lapland (fays Linnaeus), we fee the moft -Ajnoen'
evident proofs how far rivers contribute to depofite theAcad’
feeds of plants. I have feen Alpine plants growing up¬
on their ffiores frequently 36 miles diftant from the Alps;
for their feeds falling into the rivers, and being carried
along and left by the ftream, take root there.—We may
gather likewife from many circumftances how much the
fea furthers this bufmefs.—In Rollagia, the ifland of
Graefeea, Oeland, Gothland, and the Ihores of Scania,
there are many foreign and German plants not yet na¬
turalized in Sweden. The centaury is a German plant,
whofe feeds being carried by the wind into the fea, the
waves landed this foreigner upon the coafts of Sweden.
I was aftonilhed to fee the veronica maritima, a German
plant, growing at Tornea, which hitherto had been found
only in Graefoea : the fea was the vehicle by which this
plant was tranfported thither from Germany ; or poffibly
it was brought from Germany to Graefoea, and from
thence to Tomea. Many have imagined, but erroneoufly,
that feed corrupts in w'ater, and lofes its principle of ve¬
getation. Water at the bottom of the fea is feldom warm
enough to deftroy feeds 5 we have feen water cover the
furface of a field for a wffiole winter, while the feed
which it contained remained unhurt, unltfs at the be¬
ginning of fpring the waters were let down fo low by
drains, that the warmth of the fun -beams reached to the
bottom. Then the feeds germinate, but prefently be¬
come putrefcent; fo that for the reft of the year the
earth remains naked and barren. Rain and fliowers
carry feeds into the cracks of the earth, ftreams, and
rivers ; which laft, conveying them to a diftance from
their native places, plant them in a foreign foil.”
8. Laftly, fome feeds affift their proje&ion to a di¬
ftance in a very furprifing manner. The crupina, a fpe¬
cies of centaury, has its feeds covered over with ereft
briftles, by whofe affiftance it creeps and moves about in
fuch a manner, that it is by no means to be kept in the
hand. If you confine one of them between the flock¬
ing and the foot, it creeps out either at the fleeve or
neck-band, travelling over the whole body. If the
bearded oat, after harveft, be left with other grain in
the barn, it extricates itfelf from the glume; nor does
it flop in its progrefs till it gets to the walls of the build¬
ing. Hence, fays Linnaeus, the Dalecarlian, after he has
cut and carried it into the barn, in a few' days finds all
the glumes empty, and the oats feparate from them ; for
every oat has a fpiral arifta or beard annexed to it, which
is contrafted in wet, and extended in dry v’eather.
When the fpiral. is con traded, it drags the oat along
with it: the arifta being bearded with minute hairs
pointing downward, the grain neceffarily follows it 5 but
when it expands again, the oat does not go back to its
former place, the roughnefs of the beard the contrary
way preventing its return. If you take the feeds of equi-
fetum, or fern, thefe being laid upon paper, and viewed
in a microfcope, will be feen to leap over any obftacle as
if they had feet j by which they are feparated and dit-
perfed one from another j fo thpt a pcrfon ignorant of
P L A [ 608 ] P L A
Plant. t'hJs property would pronounce tliefe feeds to be fo many
«—y-—— mj|es or fmail jnfefts.
\\ e cannot finitb this article without remarking, that
many ingenious men believe that plants have a power of
perception. Of this opinion we (hall now give an ac¬
count from the fecond volume of the Manchefter Tranf-
aftions, where we find fome /peculations on the percep¬
tive power of vegetables by Dr Peraval, who attempts
to fhow, by the feveral analogies of organization, life,
inilinfl, fpontaneity, and felf-motion, that plants, like
animals, are endued with the powers both of perception
and enjoyment. The attempt is ingenious, and is in-
genioufly fupported, but in our opinion fails to con¬
vince. That there is an analogy between animals and
vegetables is certain ; but we cannot from thence con¬
clude that they either perceive or enjoy. Botanifts have,
it is true, derived from anatomy and physiology, almoft
all the terms employed in the defeription of plants. But
we cannot from thence conclude, that their organization,
though it bears an analogy to that of animals, is the fign
of a living principle, if to this principle we annex the idea
ef perception ; yet fo fully is our author convinced of the
truth of it, that he does not think it extravagant to
fuppofe, that, in fome future period, perceptivity may
be difeovered to extend even beyond the limits now af-
figned to vegetable life. Corallines, madrepores, mille-
pores, and fponges, were formerly confidered as foffil bo¬
dies : but the experiments of Count Marfigli evinced,
that they are endued with life, and led him to clafs them
with the maritime plants. And the obfervaiions of El¬
lis, Juflfieu, and Peyfonel, have fince railed them to the
rank of animals. The deteftion of error, in long ella-
blifhed opinions concerning one branch of natural know¬
ledge, jullifies the fufpicion of its exiftence in others,
which are nearly allied to it. And it will appear from
the profecution of our inquiry into the inftinfts, fpon¬
taneity, and felf-moving power of vegetables, that the
Jufpicion is not without foundation.
He then goes on to draw a comparifon between the
inilincts of animals and thofe of vegetables ; the calf, as
foon as it comes into the world, applies to the teats of
the cow •, and the duckling, though hatched under a hen,
runs to the water.
“ In it in ers analogous to thefe (fays our author), ope- Plant,
rate with equal energy on the vegetable tribe. A leed ——v—
contains a germ, or plant in miniature, and a radicle,
or little root, intended by nature to fupply it with nou-
rifhment. If the feed be fown in an inverted pofition,
ftill each part purfues its proper dire&ion. Theplumula
turns upward, and the radicle ftrikes downward into
the ground. A hop-plant, turning round a pole, follows
the courfe of the fun, from fouth to weft, and foon dies,
when forced into an oppofite line of motion: but re¬
move the obftacle, and the plant will quickly return to
its ordinary pofition. The branches of a honeyfuckle
fhoot out longitudinally, till they become unable to bear
their own weight ; and then ftrengthen themfelves, by
changing their form into a fpiral: when they meet with
other living branches, of the fame kind, they coalefce,
for mutual fupport, and one fpiral turns to the right and
the other to the left •, thus feeking, by an initinctive im-
pulfe, fome body on which to climb, and increafing the
probability of finding one by the diverfity of their courfe :
for if the auxiliary branch be dead, the other uniformly
winds itfelf round from the right to the left.
“ Thefe examples of the inltin&ive economy of vege¬
tables have been purpofely taken from fubjedfs familiar
to our daily obfervation. But the plants of warmer cli¬
mates, were we fufticiently acquainted with them, would
probably furnifh better illuftrations of this acknowledged
power of animality : and I (hall briefly recite the hiftory
of a very curious exotic, which has been delivered to us
from good authority} and confirmed by the obfervations
of feveral European botanifts.”
The dodlor then goes on to give a defeription of the
dioncea mufcipula (b), for which fee vol. vi. p. 32.; and
concludes, that if he has furnifhed any prefumptive
proof of the inftindtive power of vegetables, it will necel-
farily follow that they are endued with fome degree of
fpontaneity. More fully to evince this, however, the
doftor points out a few of thofe phenomena in the vege¬
table kingdom which feem to indicate fpontaneity.—
“ Several years ago (fays he), whilft engaged in a courfe
of experiments to afeertain the influence of fixed air on
vegetation, the following fad! repeatedly occurred to me.
A fprig of mint, fufpended by the root, with the head
downwards,
(b) Dr Watfon, the bifliop of Landaff, who has efpoufed the fome fide of the queftion with Dr Percival (fee
the ^th vol. of his Chemical Eflays), reafons thus on the motions of vegetables. “ W hatever can prouuce any
fcffea (fays he) upon an animal organ, as the impadl of external bodies, heat and cold, the vapour of burning
fulphur, of volatile alkali, want of air, &c. are found to ad alfo upon the plants c-A\tAfen/tive. But not to mfift
upon any more inftances,themufcular motions of the dionsea mufcipula, lately brought into Europe from America,
feem far fuperior in quicknefs to thofe of a variety of animals. Now to refer the rmifcular motions of lhell-fifli
and zoophytes to an internal principle of volition, to make them indicative of the perceptivity of the being, and
to attribute the more notable ones of vegetables to certain mechanical dilatations and contradlions oi parts occa-
fioned by external impulfe, is to err againft that rule of philofophizing which afligns the fame caufes for eflecks ol
the fame kind. The motions in both cafes are equally accommodated to the prefervation of the being to which
they belong, are equally diftind! and uniform, and fliould be equally derived from mechaniim, or equally admitted
as criterions of perception.
“ I am fenfible that thefe and other fimilar motions of vegetables may by fome be con foered analogous to
the automatic or involuntary motions of animals ; but as it is not yet determined amongft the phyfiologifts, whe¬
ther the motion of the heart, the periftaltic motion of the bowels, the contradlions obfervable upon external im¬
pulfe in the mufcles of animals'deprived of their heads and hearts, be attributable to an irritability unaccompanied
with perceptivity, or to an uneafy fenfation, there feems to be no reafon for entering into fo obfeure a difqmfition 5
efpecially fince irritability, if admitted as the caufe of the motions of vegetables, mull a fortiori be admitted as the
.caufe of the lefs exquifite and difcernible motions of being univerfally referred to the animal kingdom.
2
P L A [ 609 ] P L A
Phnts. downwards, in the middle glafs veffel of Dr Noolh’s
machine, continued to thrive vigoroufly, without any
other pabulum than what was fupplied by the ftream of
mephitic gas to which it was expofcd. In 24 hours
the ftem formed into a curve, the head became eredt, and
gradually afcended towards the mouth of the veffel j thus
producing, by fucceflive efforts, a new and unufual con¬
figuration of its parts. Such exertions in the fprig of
mint, to redtify its inverted pofition, and to remove from
a foreign to its natural element, feems to evince evoii-
tion to avoid what was evil, and to recover what had
been experienced to be good. If a plant, in a garden-
pot, be placed in a room which has no light except from
a hole in the wall, it will (hoot towards the hole, pafs
through it into the open air, and then vegetate upwards
in its proper diredtion. Lord Karnes relates, that,
‘ among!! the ruins of New Abbey, formerly a mona-
fiery in Gallowav, there grows on the top of a wall a
plane tree, 20 feet high. Straitened for nourifhment
in that barren fituation, it feveral years ago diredled
roots down the fide of the wall till they reached the
ground ten feet below: and now the nourifhment it
afforded to thefe roots, during the time of defcending,
is amply repaid ; having every year fince that time made
vigorous (hoots. From the top of the wall to the fur-
face of the earth, thefe roots have not thrown out a
fingle fibre, but are now united into a pretty thick
hard root.’
“ The regular movements by which the fun-flower
prefents its fplendid difk to the fun have been known to
naturalifls, and celebrated by poets, both of ancient and
modern times. Ovid founds upon it a beautiful ftory j
and Thomfon defcribes it as an attachment of love to the
celeffial luminary.
‘ But one, the lofty follower of the fun,
‘ Sad when he fets, (huts up her yellow leaves,
‘ Drooping all night j and when he warm returns,
‘ Points her enamour’d bofom to his ray.’
Summer, line 216.
Dr Percival next touches on motion •, he mentions co-
* See Ten- rallines, fea-pens *, oyfiers, &c. as endued with the power
natula, Of- of motion in a very fmall degree, and then he fpeaks in
trea, Myti- the following manner. “ Mr Pvliller (fays he), in his
*us> "" late account of the ifland of Sumatra, mentions a fpe-
cies of coral, which the inhabitants have miftaken for a
plant, and have denominated it lalan-cout, or fea-grafs.
It is found in (hallow bays, where it anpears like a flraight
Hick, but xvhen touched withdraws itfelf into the fand.
Now if felf-moving faculties like thefe indicate ani¬
mality, can fuch a diftiniffion be denied to vegetables,
poflefled of them in an equal or fuperior degree ? The
water-lily, be the pond deep or {hallow in which it grows,
pufhes up its flower-ffems till they reach the open air,
that the farina fecundans may perform without injury
its proper office. About feven in the morning the ftalk
erefts itfelf, and the flowers rife above the furface of the
water : in this (late they continue till four in the after¬
noon, when the ftalk becomes relaxed, and the flowers
fink and clofe. The motions of the fenfitive plant have
been long noticed with admix-ation, as exhibiting the
moft obvious figns of perceptivity. And if we admit
fu> h motions as criteria of a like power in other be¬
ings, to attribute them in this inftance to mere mecha-
Vol. XVI. Part II.
nifm, a£luated folely by external impulfe, is to deviate
from the foundeft rule of philofophizing, which directs
us not to multiply caufes when the effedts appear to be
the fame. Neither will the laws of eledtricily better
folve the phenomena of this animated vegetable : for its
leaves are equally affefted by the contadt of eledtric and
non-eledlric bodies j ftrow no change in their fenfibility
whether the atmofphere be dry or moift j and inftantly
clofe when the vapour of volatile alkali or the fumes of
burning fulphur are applied to them. The powers of
chemical ftimuli to produce contradlions in the fibres of
this plant may perhaps lead fome philofophers to refer
them to the vis injita, or irritability, which they affign
to certain parts of organized matter, totally diftindi from,
and independent of, any femient energy. But the hy-
pothefis is evidently a folecifm, and refutes itfclf. For
the prefence of irritability can only be proved by the ex¬
perience of irritations, and the idea of irritation involves
in it that of feeling.
“ But there is a fpecies of the order of decandria,
which conftantly and uniformly exerts a fell-moving
power, uninfluenced either by chemical ftimuli, or by
any external impulfe whatfoever. This curious fhrub,
which was unknown to Linnaeus, is a native of the Eaft
Indies, but has been cultivated in feveral botanical gar¬
dens here. I had an opportunity of examining it in the
colledlion of the late Dr Brown. See Hedysarum.—
I cannot better comment on this wonderful degree of
vegetable animation than in the words of Cicero. Ina-
nimum ejl omne quodpulfu agitatur externo ; quod autem
eji animal, id motu cietur interiore et fuo.
“ I have thus attempted, with the brevity prefcribed
by the laws of this fociety, to extend our views of ani¬
mated nature ; to gratify the mind with the contempla¬
tion of multiplied acceflions to the general aggregate of
felicity ; and to exalt our conceptions of the wifdom,
power, and beneficence of God. In an undertaking ne¬
ver yet accomplifhed, difappointment can be no difgrace:
in one direfted to fuch noble objefts, the motives are a
juftification, independently of fuecefs. Truth, indeed,
obliges me to acknowledge, that I review my fpecula-
tions with much diffidence \ and that I dare not pre¬
fume to expedl they will produce any permanent con¬
viction in others, becaufe I experience an inftability of
opinion in myfelf. For, to ufe the language of Tully,
Nefcio quomodo, dum lego, affentior; cum pofui librum,
ajfenjio omnis ilia clabitur.—But this fcepticifm is per¬
haps to be afcribed to the influence of habitual precon¬
ceptions, rather than to a deficiency of reafonable proof.
For befides the various arguments which have been ad¬
vanced in favour of vegetable perceptivity, it may be
further urged, that the hypothefis recommends itfelf by
its confonance to thofe higher analogies of nature, which
lead us to conclude, that the greateft poffible fum of
happincfs exifts in the univerfe. The bottom of the
ocean is overfpread with plants of the moft luxuriant
magnitude. Immenfe regions of the earth are covered
with perennial forefts. Nor are the Alps, or the An¬
des, deftitute of herbage, though buried in deeps of
fnow. And can it be imagined that fuch profufion of
life fubfifts without the leaf! fenfation or enjoyment ?
Let us rather, with humble reverence, fuppofe, that ve¬
getables participate, in fome low degree, of the common
allotment of vitality j and that our great Creator hath
4 H apportioned
Phrt?.
P L A
Plant?, apportioned good to all living things, ‘ in number,
v”' * 1 weight, and mearure.” See SENSITIVE Plant, Mimo¬
sa, Dionma Mufcipula, Vegetable MOTION, &c.
To thefe ingenious and fpirited obfervations, we fhall
fubjoin nothing of our own, but leave our readers to
determine for themfelves(c). Speculations of this kind,
when carried on by fober men, will never be productive
of bad confequences j but by the fubtle fceptic, or the
more unwary inquirer, they may be made the engine of
very dangerous errors. By this we do not mean to in-
finuate that the fpirit of inquiry fhould be fuppreffed,
becaufe that fpirit, in the hands of weak or of wicked
men, may be abufed. By thofe, however, who know
the bad confequences that may be drawn, and indeed
that have been drawn, from the opinions we have now
given an account of, our caution will not be deemed im¬
pertinent.
PLANTS growing on Animals. See INSECTS giving
root to Plants.
Sexes of Plants. See Sexes and Botany.
Colours of Plants. See Colour of Plants.
Colours extractedfrom PLANTS. See COLOUR-mak-
ing.
Method of Drying and Preferving PLANTS for Bota-
nifs.—Many methods have been devifed for the prefer-
vation of plants: we lhall relate only thofe that have
been found moft fuccefsful.
Wither- Firft prepare a prefs, which a workman will make by
ing's Bota-[ the following directions. Take two planks of wood not
nical Ar- liable to warp. The planks muft be two inches thick,
enngemetit, j g inches long, and 12 inches- broad. Get four male
p and four female ferews, fuch as are commonly ufed for
* fecuring fath windows. Let the four female ferews be
let into the four corners of one of the planks, and cor-
refponding holes made through the four corners of the
other plank for the male ferews to pafs through, fo as to
allow the two planks to be ferewed tightly together. It
will not be amifs to face the beariHg of tire male ferews
upon the wTood with iron plates 5 and if the iron plates
went acrofs from corner to corner of the wood, it would
be a good fecurity againft the warping.
Secondly, get half a dozen quires of large foft fpengy
paper (fuch as the ftationers call blojfom blotting paper
is the bell), and a few (lieets of flrong pafteboard.
The plants you wifh to preferve xhould be gathered
in a dry day, after the fun hath exhaled the dew ; ta¬
king particular care to colled: them in that date where¬
in their generic and fpecinc charaders are moil confpi-
cuous. Carry them home in a tin box nine inches
long, four inches and a half wide, and one inch and a
half deep. Get the box made of the thinned tinned
iron that can be procured ; and let the lid open upon
hinges. If any thing happen to. prevent the immediate
life of the fpecimens you have colieded, they will be
P L A
kept frefh two or three days in this box much better Plants.
than by putting them in water. When you are going ' v" ;
to preferve them, fuffer them to lie upon a table until
they become limber ; and then they fliould be laid upon
a padeboard, as much as poffible in their natural form,
but at the fame time with a particular view to their ge¬
neric and fpecilic characters. For this purpofe it will
be advifeable to feparate one of the flowers, and to dif-
play the generic character. If the fpecific character de¬
pend upon the flower or upon the root, a particular
difplay of that will be likewife neceffary. When the
plant is thus difpofed upon the padeboard, cover it with
eight or ten layers of fpongy paper, and put it into the
prefs. Exert only a fmall degree of preffure for the
fird two or three days; then examine it, unfold any un¬
natural plaits, reCtify any midakes, and, after putting
frefli paper over it, ferew the prefs harder. In about
three days more feparate the plant from the padeboard,
if it is fufliciently firm to allow of a change of place j put
it upon a frefh padeboard, and, covering it with frefh
bloflbm paper, let it remain in the prefs a few days lon¬
ger. The prefs fhould dand in the funfliine, or within
the influence of a fire.
When it is perfectly dry, the ufual method is to fa-
den it down, with pade or gum water, on the right-
hand inner page of a fheet of large drong waiting-
paper. It requires fome dexterity to glue the plant
neatly dowm, fo that none of the gum or pafle may
appear to defile the paper. Prefs it gently again for
a day or two, with a half flieet of bloffom-paper be-
txvixt the folds of the waiting paper. When it is quite
dry, write upon the left-hand inner page of the paper
the name of the plant; the fpecific charafter j the
place where, and the time wiren, it was found 5 and
any other remarks you may think proper. Upon the
back of the fame page, near the fold of the papert
write the name of the plant, and then place it in your
cabinet. A fmall quantity of finely powdered arfenic,
or corrofive fublimate, is ufually mixed with the pade
or gum-water, to prevent the devadations of infefts \
but the feeds of daves-acre finely powdered will an-
fvver the fame purpofe, without being liable to cor¬
rode or to change the colour of the more delicate
plants. Some people put the dried plants into the
fheets of writing paper, without fadening them down at
all; and others only faden them by means of fmall flips
of paper, parted acrofs the dem or branches. Where
the fpecies of any genus are numerous, and the fpecimens
are fmall, feveral of them may be put into one flieet of
paper.
Another more expeditious method is to take the plants
out of the prefs after the fird or fecond day ; let them
remain upon the padeboard 5 cover them with five or
fix leaves of bloifom paper, and iron them with a hot
fmoothing
[ 610 1
(c) In the 2d volume of Tranfa&ions of the Linncean Society, we find Dr Percival’s reafoning very ably com¬
bated, as far as he drawrs his confequences from the external motions of plants ; where it is argued, that thefe mo-
t ons, though in fome refpefts fimilar to thofe of animals, can and ought to be explained, without concluding that
they are endowed either with perception or volition. Mr Townfon concludes his paper in thefe words : “ When all
is confidercd (fays he), I think we ftiall place this opinion among the many ingenious flights of the imagination,
and foberly follow7 that blind impulfe which leads us naturally to give fenfation and perceptivity to animal life, and
to deny it to vegetables 5 and fo dill fay with Aridotle, and our great mader Linnaeus, Vegetcbilia crefeunt <&' vi-
vunt; animalia crefeunt^ vivunt, <b' fentiunt.”
P L A [ ] P L A
Plant?, fmootliing iron Until they are perfectly dry. If the iron be
^ too hot, it will change the colours j but fome people,
taught by long praClice, will fucceed very happily. This
is quite the belt method to treat the orchis and other Ui-
my mucilaginous plants.
Another method is to take the plants when frefh ga¬
thered, and, inftead of putting them into the prefs, im¬
mediately to fallen them down to the paper with lirong
gum water : then dip a camel-hair pencil into fpirit-var-
nilh, and varnifh the whole furface of the plant two or three
times over. This method fucceeds very well with plants
that are readily laid flat, and it preferves their colours better
than any other. The fpirit varnilh is made thus. To
a quart of highly redlified fpirit of wine put five ounces
of gum fandarach ; two ounces of maflich in drops ; one
ounce of pale gum elemi, and one ounce of oil of fpike-
lavender. Let it Hand in a warm place, and lhake it
frequently to expedite the folution of the gums.
Where no better convenience can be had, the fpeci-
mens may be difpofed fyftematically in a large folio
book ; but a vegetable cabinet is upon all accounts more
eligible. With the afliltance of the following defcrip-
tion a workman may readily make one. The drawers
mull have backs and fides, but no other front than a
fmall ledge. Each drawer will be 14 inches wide, and
10 inches from the back to the front, after allowing half
an inch for the thicknefs of the two fides, and a quarter of
an inch for the thicknefs of the back. The fides of the
drawers, in the part next the front, mull be fleped off
in a ferpentine line, fomething like what the workmen
call an ogee. The bottoms of the drawers mull be made
to Hide in grooves cut in the uprights, fo that no fpace
may be loll betwixt drawer and drawer. After allow¬
ing a quarter of an inch for the thicknefs of the bottom
of each drawer, the clear perpendicular fpace in each
muff be as in the following table.
T. Two tenths of an inch.
II. One inch and two-tenths.
III. Four inch, and fix-tenths.
IV. Two inches and three-
tenths.
V. Seven inches knd eight-
tenths.
VI. Two inches and two-
tenths.
"VIT. Two tenths of an inch.
VIII. One inch and four-tenths.
TX. Two-tenths of an inch.
X. Two inches and eight-
tenths.
XT. One inch and two-tenths,
XII. Three inches and five-
tenths.
XIII. Two inches and four-
tenths^
XIV. Three inches and eight-
tenths.
XV. Three inches and four-
tenths.
XVI. One inch and three-
tenths.
XVII. Two inches and eight-
tenth'.
XVIII. Six tenths of an inch.
XIX. Ten inches.
XX. One inch and nine-
tenth'. ?
XXI. Four inches and four-
tenths.
XXII. Two inches and fix-
tenths.
XXIII. One inch and two-
tenths.
XXIV. Seventeen inches.
This cabinet Ihuts up with two doors in front} and
the whole may Hand upon a bafe, containing a few
drawers for the reception of duplicates and papers.
Fo/fi/ PLANTS. Many fpecies of tender and herba¬
ceous plants are found at this day, in great aboundance,
buried at confiderable depths in the earth, and converted,
as it were, into the nature of the matter they lie among 5
foffil wood is often found very little altered, and often
impregnated wTith fubftances of almoft all the different
foffil kinds, and lodged in all the feveral ftrata, fome-
txmes firmly imbedded in hard matter; fometimes loofe :
but this is by no means the cafe with the tenderer and
more delicate fubje&s of the vegetable world. Thefe Plants,
are ufually immerfed either in a blackiffi flaty fubftance, l _v
found lying over the ftrata of coal, elfe in loole nodules
of ferruginous matter of a pebble-like form, and they are
always altered into the nature of the fubftance they lie
among: what we meet with of thefe are principally of
the fern kind j and what is very fingular, though a very
certain truth, is, that thefe are principally the ferns of
American growth, not thofe of our own climate. The
moft frequent foffil plants are the polypody, fpleenwort,
ofmund, trichomanes, and the feveral larger and fmaller
ferns \ but befides thefe there are alfo found pieces of the
equifetum or horfe-tail, and joints of the ftellated plants,
as the clivers, madder, and the like ; and thefe have been
too often miftaken for flowers; fometimes there are alfo
found complete graffes, or parts of them, as alfo reeds,
and other watery plants 5 fometimes the ears of corn,
and not unfrequently the twigs or bark, and impreffions
of the bark and fruit of the pine or fir kind, which have
been, from their fcaly appearance, miftaken for the fkins
of fifhes} and fometimes, but that very rarely, we meet
with moffes and fea-plants.
Many of the ferns not unfrequently found, are of
very fingular kinds, and fome fpecies yet unknown to
us, and the leaves of fome appear fet at regular diftan-
ces, with round protuberances and cavities. The Hones
which contain thefe plants fplit readily, and are often
found to contain, on one fide, the impreffion of the
plant, and on the other the prominent plant itfelf j
and, befide all that have been mentioned, there have
been frequently fuppofed to have been found with us
ears of common wheat, and of the maize or Indian corn j
the firft being in reality no other than the common end-
moft branches of the firs, and the other the thicker
boughs of various fpecies of that and of the pine kind,
with their leaves fallen off} fuch branches in fuch a
ftate cannot but afford many irregular tubercles and pa¬
pillae, and, in fome fpecies, fuch as are more regularly
difpofed.
Thefe are the kinds moft obvious in England ; and
thefe are either immerfed in the flaty Hone which confti-
tutes whole ftrata, or in flatted nodules ufually of about
three inches broad, which readily fplit into two pieces
on being ftruck.
They are moft common In Kent, in coal-pits near
Newcaftle, and the foreft of Dean in Gloucefterffiire j
but are more or lefs found about almoft all our coal-pits,
and many of our iron mines. Though thefe feem the
only fpecies of plants found with us, yet in Germany
there are many others, and thofe found in different fub¬
ftances. A whitifh ftone, a little harder than chalk,
frequently contains them: they are found alfo often in
a gray flaty ftone of a firmer texture, not unfrequently
in a blackifh one, and at times in many others. Nor
are the bodies themfelves lefs various here than the mat¬
ter in which they are contained : the leaves of trees are
found in great abundance, among which thofe of the
willow, poplar, white thorn, and pear trees, are the
moft common •, ftnall branches of box, leaves of the
olive tree, and ftalks of garden thyme, are alfo found
there; and fometimes ears of the various fpecies of
corn, and the larger as well as the fmaller moffes in
great abundance.
Thefe feem the tender vegetables, or herbaceous
plants, certainly found thus immerfed in hard ftone, and
4 H 3 buried
Plants
i(
Plantago
P L A [ 61
buried at great depths in the earth : others of many kinds
there are aifo named by authors ; but as in bodies fo im-
, perfect errors are ealily fallen into, thele feem all that
can be afeertained beyond mere conjecture.
PLANTS, method qf preferving them in their original
Jkape and colour. Waih a lufficient quantity of fine rand,
fo as perfectly to feparate it from all other fubitances}
dry it j pais it through a fieve to clear it from any grofs
particles which would not rife in the wTalhing : take an
earthen veflel of a proper fize and form, for every plant
and dower which you intend to preferve ; gather your
plants and flowers when they are in a ftate of perfection,
and in dry weather, and always with a convenient por¬
tion of the italk : heat a little of the dry fand prepared
as above, and lay it in the bottom of the veffel, fo as
equally to cover it; lay the plant or flower upon it fo
as that no part of it may touch the fides of the vefl'el:
lift or ihake in more of the fame fand by liule upon it,
fo that the leaves may be extended by degrees, and with¬
out injury, till the plant or flower is covered about two
inches thick : put the vefiel into a ftove, or hot-houie,
heated by little and little to the 50th degree} let it
Hand there a day or two, or perhaps more, according to
the thicknefs and fucculence of the flower or plant j
then gently (hake the fand out upon a llieet of paper,
and take out the plant, which you will find in all its
beauty, the fhape as elegant, and the colour as vivid as
when it grew.
Some flowers require certain little operations to pre¬
ferve the adherence of their petals, particularly the tu-
rvith refpeCt to which it is neceffary, before it is bu¬
ried in the fand, to cut the triangular fruit which rifes in
the middle of the flower ; for the petals will then remain
more firmly attached to the ftalk.
A hortus ficcus prepared in this manner would be
one of the moll beautiful and ufeful curiofiiies that
can be. ■'
Moving Plant. See Hedysarum, Botany Index.
Sea Plants. See Sea Plants.
Senjitive Plant. See Mimosa, Botany Index.
PLANT Lice, Vine-fretters, or Pucerons. See Aphis,
Entomology Index.
PLANTA, a Plant. See Plant.
PLANTA Fceminea, a female plant, is one which bears
female flowers only. It is oppofed to a male plant,
which bears only male flowers; and to an androgynous
one, which bears flow-ers of both fexes. Female plants
are produced from the fame feed with the male, and ar¬
range themfelves under the clafs of dioecia in the fexual
method.
PLANTAGENET, the furname of the kings of
England from Henry II. to Richard III. inclufive. An¬
tiquarians are much at a lofs to account for the origin
of this name; and the befi: derivation they can find for
it is, that Fulk, the firfl: earl of Anjou of that uame,
being flung with remorfe for fome wicked a ft ion, went
in pilgrimage to Jerufalem as a w ork of atonement;
where, being foundly fcourged with broom twigs, wdiich
grew plentifully on the fpot, he ever after took the fur-
name of Plantagenet or broomjlalh, wdiich was retained
by his noble pofterity.
PLANTAGO, Plantain ; a genus of plants be¬
longing to the tetrandria clafs. See Botany Index.—
Of the plantain there are the following fpecies : The
common broad-leaved plantain, called waybred, or way-
i!
Planter.
(hip.
2 ] P L A
born ; becaufe it commonly grows by the wTayfide ; the Plantain
great hoaiy plantain, or lambs-tongue; the narrow-lea¬
ved plantain, or ribwort.
PLANl AIN. See Plantago, Botany Index. ^
P LANTAIN -Tree. See Musa, BOTANY Index.
PLANTATION, in the Weft Indies, denotes a
fpot ot ground which a planter, or perfon arrived in a
new colony, pitches on to cultivate for his own uie, or
is afiigncd for that purpole. However, the term plan¬
tation is often uled in a term lynonymous with colony.
See Colony.
PLANTERSHIP, in a general fenfe, the bufmefs
of a planter.
Plantership, in the Weft Indies, denotes the ma.
nagement ot a iugar plantation, including not only the
cultivation of the cane, but the various proceiies lor the
extraction ot the iugar, together with the making of iu-
gar-fpirits. See Rum, Saccharum, and Sugar.
'To effect a deiign lo comprehenfive, it is neceflary for
a planter to underhand every branch ot the art preexiely,
and to ule the utmoft attention and caution both in the
laying down and executing of his plans. It is theie-
fore the duty of a good planter to inipeft every part of
his plantation with his own eyes ; to place his provilions;
flores, and utenlils, in regular order, and in late repoli-
tories ; that by preferving them in perfeftion, all kinds
of wafte may be prevented.
But as negroes, cattle, mules, and horfes, are as it
were the nerves of a fugar-plantation, it is expedient to
treat that fubjefl with iome accuracy.
Of Negroes, Cattle, &c.]. In the firft place, then, as
it is the intereft oi every planter to preferve his negroes
in health and ftrength ; lo every aft of cruelty is not leis
repugnant to the mailer’s real profit, than it is contrary
to the law's of humanity : and if a manager confiders his
owm eafe and his employer’s intereft, he will treat all
negroes under his care with due benevolence ; for good
difeipline is by no means inconfiftent with humanity : on.
the contrary, it is evident from experience, that he who
feeds his negroes well, proportions their labour to thftr
age, fex, and flrength, and treats them with kindnefs
and good nature, will reap a much larger product, and
w ith infinitely more eafe and felf-fatisfaftion, than the
moft cruel talkmafter, who ftarves his negroes, or cha-
ftifes them with undue feverity. Every planter then who j\ja}fin e,
wilhes to growr rich with eafe, mull be a good economift; Tlanter-
muft feed his negroes with the moft whoiefome food, fuf-Jbip.
ficient to preferve them in health and vigour. Common
experience points out the methods by w’hich a planter
may preferve his people in health and ftrength. Some
of his moft fruitful land fhould be allotted to each negro
in proportion to his family, and a fufficient portion of
time allowed for the cultivation of it ; but becaufe fuch
allotment cannot in long droughts produce enough for
his comfortable fupport, it is the incumbent duty of a
good planter to have always his ftores well filled with
Guinea corn, yams, or eddoes, befidcs potatoes growing
in regular fucctffion : for plenty begets cheerfulnefs of
heart, as well as ftrength of body ; by which more wTork
is effefted in a day by the fame hands than in a w’eek
when enervated by want and feverity. Scanty meals
may fuftain life ; but it is evident, that more is requifite
to enable a negro or any other perfon to go through the
necefiary labours. He, therefore, who will reap plenti¬
fully, muft plant great abundance of provifions as well
P L A [ 613 ] P L A
Plant-er- as fugar-canes •, and it is nature’s economy fo to fructify
the ioii by the growth of yams, plantains, and potatoes,
”"_y as to yield better harvefts of fugar, by that very means,
than can be produced by many other arts of cultivation.
Plantains are the principal fupport of all the negroes in
Jamaica 5 and are alfo much cultivated, at great expence
ot manure, in Barbadoes ; but ought not to be folely de¬
pended upon in climates fubjedt to hurricanes. A cele¬
brated planter and economilt of the lalt-mentioned illand,
who raifed an immenfe fortune from very fmall begin¬
nings only by planting, affirmed, that he fed conftantly
at leal! 300 negroes out of 12 acres of plantains. How
that excellent produce came to be fo long negledted in
foine of the illands it is hard to guefs ; but at prefent
the negledt ieems to be founded upon a vulgar error,
that plantains cannot thrive in any other than low moiit
foils. In fuch places, no doubt, they Hourilh mod lux¬
uriantly j but yet they thrive and bear fruit abundantly
on mountains and in marfhes, and in the drielt black
mould upon marie or rocks, and even in ffiarp gravelly
foils, as may be evinced by num’oerlefs indances.
However plenty of wholefome food may be condu¬
cive to health, there are alio other means, equally necef-
fary to the drength and longevity of negroes, well worth
the planter’s attention : and thofe are, to choofe airy
dry fituations for their houfes 5 and to obferve frequently
that they be kept clean, in good repair, and perfeftly
water-tight; for nadinefs, and the inclemencies of wea¬
ther, generate the mod malignant difeafes. If thefe
houfes are fituated alfo in regular order, and at due
didances, the fpaces may at once prevent general deva¬
luations by fire, and furniih plenty of fruits and pot¬
herbs, to pleafe an unvitiated palate, and to purify the
blood. Thus then ought every planter to treat his ne¬
groes with tendernefs and generofity, that they may be
induced to love and obey him out of mere gratitude, and
become real good beings by the imitation of his beha¬
viour ; and therefore a good planter, for his own eafe
and happinefs, will be careful of fetting a good ex¬
ample.
Having thus hinted the duties of a planter to his ne¬
groes, let the next care be of cattle, mules, and horfes.
The planters of Barbadoes (who are perhaps the mod
ibilful of all others, and exadt to a nicety in calculations
of profit and lofs), are, with refpedl to their cattle, the
mod remils of any in all the iflands ; as if the carriage of
canes to the mill, and of plantation-produce to the mar¬
ket, was not as eflential as any other branch of planter-
fhip. At Barbadoes, in particular, the care of thefe
animals is of more importance : becaufe the foil, worn
out by long culture, cannot yield any produce wuhout
plenty of dung. Some planters are neverthelefs fo in-
gemoufly thrifty, as to carry their canes upon negroes
heads ; adling in that refpedl diametrically oppofite to
their own apparent intereft, which cannot be ferved
more effedfually than by faving the labour of human
hands, in all cafes where the labour of brutes can be
fubdituted ; and for that end, no means of preferving
thofe creatures in health and drength ought to be ne¬
glected.
I he fird care therefore is to provide plenty and va¬
riety of food. In crop-time, profufion of cane-tops may
be had for the labour of carriage ; but they will be more
whole fome and nutritious if tedded like hay by the fun’s .
heat, and fweated by laying them in heaps a few days
before they are eaten. In this feafon of abundance, Planter
great ricks of cane-tops (the butt ends turned inwards)
Ihould be made in the mod convenient corner of each
field, to lupply the want of paiturage and other food :
and thefe are very wholefome if chopped into fmall parts,,
and mixed fometimes with common fait or fprinkled
with melafles mixed with water : but yet the cattle re¬
quire change of iood to preferve them in drength : fuch
as Guinea-corn, and a variety of grafs, which eveiv foil
produces with a little care in moiit weather; and indeed
this variety is found neceffary in ail climes.
But fmce that variety is not to be had during thofe
fevere droughts to which hot climates are liable, and
much lefs in thofe fmali illands which cannot furniih
large tracts of meadow-lands for hay, the only refource
is the fodder of cane-tops or tedded Guinea-corn leaves ;
which are very nutritious, and may be preferred in per¬
fection for more than a whole year, provided the tops
or Guinea-corn are well tedded for three or four hot
days as they lie fpread in the field ; and then, being tied
into bundles or {heaves, muit lie in the hot fun for three
or four days more, when they may be fit to be put up
into ricks. Ibe bell method of making them is in an
oblong figure, about 30 feet in length, and 16 or i8-
feet wide; feven feet high at the Tides, and from thence
Hoping like the roof of an houfe, the ridge of which-
mult be thatched very carefully ; for the tides may be-
fecured from wet by placing the bundles with the butts
upwards towards the ridge, in courfes, and lapping the
upper over the lower courfe.
The bell method of forming thofe ricks is to place
the firil couri'e of bundles all over the bafe one way ;
the fecond courfe reverfely ; and fo alternately till the.
rick be. finiffied.
When cattle are to be fed with this fodder, it muft be
obferved to take down the bundles from the top, at the
weft end of the rick, to the bottom ; for all thefe ricks*
muft ftand eaft and weft lengthwile, as well to fecure
them from being overturned by high winds, as for
the convenience of preferving them from wet, which can¬
not be done when ricks are made round. By this '
huffiandry, an herd of cattle may be kept in ftrength,'
either in fevere droughts, or in wet feafons when grafs
is purgative ; and thus the neceffity or expence of
large paftures may be totally faved. The hay-knife
ufed in England for cutting hay, anfwers for cutting
ricks of tops.
I he method of tedding Guinea-corn to make a kind
of hay, will require a little explanation here. When
Guinea-corn is planted in May, and to be cut down in
July, in order to bear feed that year, that cutting, ted-,
ded properly, will make an excellent hay, which cattle
prefer to meadow hav. In like manner, after Guinea-
corn has done bearing feed, the after crop will furniih a
great, abundance of that kind of fodder which will keep
well in ricks for two or three years.
The next care of a planter is to provide ffiade for his-
cattle ; either by trees where they are fed in the heat
of the day, if his foil requites not dung ; or by building
a fiat filed over the pen where cattle are confined for
making it. 1 hat luch ffiades are effentially neceftary
to the well-being of all animals in hot weather, is appa¬
rent to every common obferver, who cannot fail of fee¬
ing each creature forfaking the moft luxuriant paftures-
in the heat of the day for the fake of fhade; thus con¬
vincing
P L A t ] P L A
' f':?-ntcr- vincing tlie ov,*hers, by inftin£Hve argument, that fliade
v is almoft as neceffary to the well-being of the brute
^”’~v creatures as food. Yet, notwithftanding that demon-
flration from the unerring ccurfe of nature, throughout
all our iilands (except in a very few inftances), thefe
poor creatures are expofed to the fccrching fun-beams
without mercy. Such inhuman negleft is not always
fo much the effedl: of inattention as of a miflaken no¬
tion that {beds are impedimental to the making of
much dung •, but a fiat (lied, covered with cane-trafh,
may be fo made as to let rain pafs through it without
admidion of fun-beams. This will do for cattle ; but
mules, which are fpirited creatures, and work them-
felves by draught into a foaming heat, fhould be put in¬
to a -warm liable, until quite cool : for turning them
loofe to pafture when fo hot, is probably the caufe of
their deflruldion by the glanders.
If the care of providing (hade for brute creatures is
fo much the duty and intereft of their owners, how
much more is it agreeable to the laws of humanity to
provide fliade for human creatures travelling upon the
high-roads in this hot climate ? Nothing furely of fo
much beauty coffs fo little expence as planting cocoa-
nut or fpreading timber trees in avenues along the high¬
ways, if each proprietor of the lands adjoining hath any
tafle of elegance, or feeling for other men : but both
thofe kinds of trees will yield alfo great profit to the
proprietor, by furnifRing him with timber, when per¬
haps not otherwife to be had j or with a delicious milk,
fitted by nature to cool the efiervefcence of the blood
in this hot region 5 and alfo to improve the fpirits made
from fugar to the delicacy and foftnefs of arrack. Co¬
coa-nut and cabbage-trees are both very beautiful and
fhady, bearing round heads of great expanfion, upon
natural trunks or pillars of elegant proportion, and of
fuch an height as to furnifh a large fhade, wuth a free
circulation of air equally refrefhing to man and beaft.
The common objeftion of injury to canes by the
roots of fuch trees growing on their borders, may be
eafily removed by digging a fmall trench between the
canes and trees, which may intercept their roots, and
oblige them to feek fuftenance in the common road.
Let it alfo be confidered, befides the benefits above fug-
gefted, that the planter will thus beautify his efiate to
the refemblauce of a moft fumptuous garden. And
probably that very beauty might not only render the
ifiands more healthful to the inhabitants, by preferving
them from fevers kindled by the burning fun-beams,
but alfo much more fruitful by making the weather more
feafonable : for as, by cutting down all its woods, an hot
country becomes more fubjeft to excefiive droughts •, fo,
by replanting it in the manner above defcribed, this in¬
convenience would probably be prevented.
Let then the planter be kind not only to his fellow-
creatures but merciful to his beafts; giving them plenty
and variety of wholefome food, clear water, cool {hade,
and a clean bed, bleeding them after a long courfe of
hard labour, currying their hides from filth and ticks (a)} Planter-
affording them fait and other phyfic when necefiary ; Ih'P-
protefting them from the flaying rope-laflies of a cruel
driver (who needs no other inltrument than a goad) j
porportioning their labour to their flrength; and by
every art rendering their work as eafy as poffible. The
general management of planters is not, perhaps, more
defedtive in any other refpedt than in this: for, by
pairing the cattle unequally, and by the drivers ill con-
du£I in writhing to the right and left, the poor creatures
are fatigued by much needlefs labour. A horfe ought
therefore to be harneffed before them as a leader. This
docile creature, by being led in a ftraight line, will foon
learn to be an unerring guide, and the cattle will fol¬
low in the fame direction with united {Length, and con-
fequently with more effedt and lefs fatigue to each indi¬
vidual.
The Portuguefe of Madeira, by their poverty and
fcantinefs of pafture, breed the fmalleft kind of cattle j
and yet one yoke of them will draw a much greater
weight than a pair of our largeft oxen, folely by an
equal exertion of their joint ftrength. That equality
or evennefs of draught is preferved by boring gimblet
holes through their horns, within two inches of the
points, and running a thong of leather through thofe
holes, fo as to tie the horns of each pair at fix inches
diftance from each other. By this ligature the pair of
cattle are abfolutely hindered from turning different
ways, and draw in an even diredtion with united force.
Thus it appears evidently from reafon, as well as from
experience, that the labour of our beafts may, by a little
contrivance, be rendered more eafy and effedlual.
Of the Culture of various Soils.^ In the Britilh fugar-
colonies there is as great a variety of foils as in any
country of Europe j fome naturally very rich or fruit¬
ful, yielding a luxuriant produdt with little labour or«
culture. This fruitful foil is of three kinds: a loofe
hazel mould mixed with fand, like that of St Chrifto-
pher’s, and is the beft in the known world for produ¬
cing fugar in great quantity, and of the beft quality.
The brick mould of J amaica is fomewhat of the fame
nature, and next in value } and then the various mix¬
tures of mould and gravel, to be found in veins or plats
over all the other iflands. When any of thefe foils are
exhaufted of their fertility by long and injudicious cul¬
ture, they may be reftored by any kind of dung rvell
rotted ; for thefe (b) warm foils cannot bear hot un~
rotten dung, without being laid fallow for a confider-
able time after it. Another improvement is by fea-
fand or fea-weed ; or by digging in the cane-trafti into
fteep lands, and by letting it lie to rot for fome months.
A third method is, by ploughing and laying it fallow ;
and the fourth method (the beft of all), is by folding
the fallows by {beep. But this can be pra&ifed only
where there are extenfive paftures; nor can the plough
be employed where the foil abounds with large ftones.
In that cafe, however, the former method df digging in
trafti
(a) One pound of native fulphur, a quart of lamp-oil, and the like quantity of nog s-laid, intimately mixed and
made into an ointment, is a cure for the mange, lice, &c. .
(b) Thefe foils, which are naturally loofe and upon marie, Mr Martin calls hot foils ; and thefe, he lays, have
been much injured in fome of the iflands by dung haftily made with marie : but if the fediment of lees were thrown
into thefe pens, after being turned over, ft would much improve the dung.
P L A [6
Planter- trafti will be nearly as effectual, thougb more expenfive,
, by hand-labour or hoe-ploughing.
The next belt foil for producing good fugar is a
mould upon clay, which if (hallow requires much cul¬
ture and good labour, or its produce wall be fmall in
quantity, though of a ftrong grain and bright colour,
lb as to yield moft profit to the refiner of any fugar,
except that produced from an hazel or gravelly foil, as
before-mentioned. All the black mould foils upon marie
are generally fruitful, and will take any kind of dung $
but yield not fo ftrong or large-grained fugar. Marie,
however, of a white, yellow, or blue colour, or rich
mould from walhes, or alhes of every kind, are excellent
for every ftrong foil, as the chief ingredient in the com-
poft of dung : cither of them will do alone for ftiff
lands j but the yellow and chocolate marie are the moft
foapy, and the richeft kind of manure (except fine
mould) for all ftiff lands. If thefe are well opened,
pulverized by culture, and mixed with hot dung, or any
kind of loofe earth or marie, they will produce as plen¬
tifully as lighter foils : and all kinds of clay-foils, except
that of a white colour, have thefe two advantages above
the fineft gravel foils, that they do not fcorch foon by
dry weather, and never grow weary of the fame manure,
as moft other foils do.
The extraordinary hand-labour beftowed in making
dung, may be faved by the art of caving, now in gene¬
ral ufe in England. Ten mules or horfes, and two light
tumbrels with broad wheels, and ten able negroes, may,
by the common ufe of fpades, fhovels, and light mat¬
tocks or grubbing hoes, make more dung than 60 able
negroes can do in the prefent methods.
If marie lies upon riling grounds, or in hillocks, as it
often does, the pit is to be opened at the foot of the
declivity $ which being dug inwards, till the bank is
three feet high, then it is to be caved thus. Dig an
hollow fpace of 12 or 18 inches deep under the foot of
the bank •, then dig into each fide of it another perpen¬
dicular cut of the fame depth, and 18 inches wide from
the top of the bank to the bottom : that being finilhed,
make a fmall trench a foot or two from the brink of
the bank •, pour into it water till full; and when that
is done, fill it again, till the water foaking downward
makes the marie feparate and fall down all at once.
This may be repeated till the pit rifes to 50 feet high j
and then many hundreds of cart-loads of marie may be
thrown down by four negroes in two hours ; from
whence it may be carted into cattle-pens, or laid out up¬
on lands, as occafion requires. Five or fix negroes with
fpades or (hovels will keep two or three tumbrels em¬
ployed, according to the diftance of cartage : and thus
as much dung may be made by ten negro men as will
dung richly at leaft 70 or 80 acres of land every year,
and laid out alfo with the afliftance of cattle-carts : An
improvement highly worthy every planter’s confideration,
wThen negroes and feeding them are fo expenfive j and
this is no fpeculation, but has been confirmed by prac¬
tice. In level lands, the fame operation may be as ef-
feftual, provided the mouth of the pit be opened by
gradual defcent to any depth : but when marie is to be
found on the fides of hills, the operation is lefs laborious
for the horfes. But if the furface of the marle-pits
(as it often happens) be covered with clay or rtiff foil,
fo that the water cannot quickly foak from the trench
above) in that cafe, pieces of hard wood, made like
5 ] P L A
piles, four feet long, and four inches fquare, pointed at
one end, and fecured at the other fquare head by an iron
clamp, may be driven by heavy mauls into the trench,
as fo many wedges, which will make the caved part
tumble down i but a (kilful eye muft watch the laft ope¬
ration, or the labourers may be buried or hurt.
But then clay foils that are level, and fubjeft to be
drowned, or to retain w'ater in ftagnated pools, can ne¬
ver be made fruitful by any kind of manure, without
being firft w'ell drained : for water lying upon any foil
will moft certainly transform it to a ftiff unfruitful clay),
as appears evidently by the bogs of Ireland, the fens of
Lincoln and Cambridgefhire, and even by the ponds of
Barbadoes fituated in the deepeft and lighted black
mould ) for that fine foil being waflred into thofe ponds,
becomes the ftiffeft blapk clay, not fit even for an ingre¬
dient in dung, until it has been laid dry, and expofed to
the fun for a whole year : but when thefe bogs and fens
are well drained, they become the moft fruitful foils.
Natural clay the celebrated Boerhaave thinks the fatteft
of all foils ) but then it muft be opened by culture,
marie, or fandy manures. It is hard to conjecture how
the opinion prevailed in the Britiflr plantations, that
fandy gut-mould w'as moft unfit for clay-foils, as being
the means of binding them to the compaftnefs of brick :
whereas it is proved, from long experience, to be one or
the beft means of opening clay foils, and rendering them
abundantly fruitful. Brick is made of day alone; no
fand being ufed in it, farther than to fprinkle the
board, on which it is moulded into drape. From re¬
peated experience it appears, that a mixture of fand in
gut-mould is the beft of all manure for ftiff and barren
clay-lands ; provided they be well drained, by throwing
the whole foil into round ridges of 12 feet wide, with
furrows of three feet wide between each ridge. And
this is done with little more hand-labour than that of
hoe-ploughing well in the common way. For if a piece
of land be marked in lines at feven feet and a half di¬
ftance from each other, and the labourers are fet in to
hoe-plough at the fecond line, hauling back each clod 12
inches) half the ridge, and near half the furrow, is made
at the fame time : and thus a piece of land may be
round-ridged, and the furrow’s all made at once, by the
common operation of hoe-ploughing, provided the dig¬
ger drives his hoe up to the eye at every ftroke. Hoe-
ploughing in clay foils that have lain long under W’ater,
is indeed hard labour ) but it will every year grow7 the
lighter by being well drained by round-ridging : and in
the meanw’hile the labour may be rendered much more
eafy by the plough condufled by the lines above de-
fcribed. As therefore fandy mould is the beft manure
for ftiff clay, fo, by parity of reafon, confirmed by long
experience, ftiff clay is the beft manure for fandy or
chaffy foils.
The method of round-ridging before defcribed, is, by
feveral years experience, found the moft effential im¬
provement of flat clayey foils : and yet there are fome
who wfill prefer fpeculation to ocular demonftration, fan¬
cying that all kinds of ridges will carry off the mould
in heavy rains. The fa& is otherwdfe in clay foils : and
plain reafon, without experience, vouches, that where
great confluxes of water are divided into many fmall rills,
the force is broken) and therefore lefs mould carried
off the land. Another objeftion made to round-ridge-
ing is, that by digging much clay to form, the fides of
the .
P L A [ 6
Planter- the ridge, the foil is impoverilhed : but this obje£Hon
, ftands good only againlt thofe ridges which are raii’ed
too high, and made too broad 5 but if land is ridged in
the manner before direfted, that is, 1 2 feet broad, and
not above fix or eight inches higher in the middle than
at the fides, the objection vanifhes. Ridges were never
propofed for light foils or fteep lands ; and even in flat
foils upon loam they ftiould be made with great cau¬
tion, becaufe loam melts away by water. But there are
poachy lands of a white clay, even upon fmall defcents,
too retentive of water ; thefe may certainly be impro¬
ved much by ridges of 12 feet wide, as above defcribed,
without fear of wafties.
But fuppofing, as the objedtion urges, that a little
clay fhould be turned up at the fides of fuch ridges, can
it not be manured fomewhat more than the other parts
with marie or fandy mould, fo as to become equally
good with any other part of the foil ? And is not this
well worth the labour, fince round-ridging not only im¬
proves the foil by draining it to a furprifing degree, but
adds one-fifth part to the depth of the ftaple f And will
not a ridge made a little rounding, throw off the water
much better than a flat ridge ?
The general maxim of npt burning cane-tralh) which
may be called the Jlubble of cane-lands') upon any kind
of foil, is furely a great miftake ; as may be evinced by
obferving the contrary practice of the bell hufbandmen
in England, where burn-baiting or baftard burn-baiting,
is found by experience an admirable method of fertili¬
zing cold, ftiff, or clayey lands. It mull indeed be a
conllant pradlice, not only for the fake of contributing
to warm and divide the foil, but as the only effectual
means of deftroying pernicious infe61s, and weeds of va¬
rious kinds, fuch as French weed, wild peafe, and wild
vines.
Soon after the difufe of burning tralh upon our lands
in the iflands, the blaft made its firfl: appearance with in¬
credible devaftation : to revive that practice therefore
feems to be the moll obvious means of expelling it. It
may be prefumed that the difufe of burning trafh was
founded upon the miftaken notion of burn-baiting,
which is turning up a thick fod of very dry, light, and
fhallow foils, and burning the whole fuperficies or ftaple
to allies. This practice the writers upon hulbandry
condemn univerfally, and very juftly: for though by this
pradlice the land wall produce two or three crops more
plentifully than ever, yet the foil is blown away by the
wand, and the fubftratum being generally an hungry
gravel or chalk, can never be reftored to fertility by the
common arts of hulbandry. But furely this has no re-
femblance to our fuperficial burning of the little tralh
we can fpare from dung : and though this method of
burn-baiting light and lhallow foils be juftly condemned,
yet the bell writers recommend that very practice in
cold, moift, and heavy foils, as is obferved above j and
long experience juftifies it.
Deep mould upon clay or loam being fubjeft to the
grub-worm (c), will not take any kind of dung, till
perfedlly rotten, except that of the (beep-fold 3 which
l6 ] P L A
is the beft manure for all kinds of light foils, and is of Planter-
all others the leaft expenfive, as not requiring^hand-la- ^lP-
hour. But the ufe of the fold is impracticable in any
ifland not abounding wdth large favannas or Iheep-pa-
ftures, as in Jamaica.
Thofe foils therefore which are fubjeft to the grub,
and muft be fertilized by common dung, which is a
proper neft for the mother-beetle to depofite its eggs,
muft be well impregnated with the brime of dilfolved
fait, after the dung is firft cut up ; two large hogfheads
of fait will make brine enough for a dung-pen of 50 feet
fquare.
This cure for the grub is a late difcovery 5 and which
has been attended with fuccefs, fo far as the experi¬
ment is made. But though it proves effectual to de-
ftroy that pernicious infeft in plant-canes, it probably
will not be fufticient to fave rattoons, without a new
application of fait in powder ; becaufe the firft brine
muft be vv alhed away by the time when rattoons fpring
■up; ,
The planter who would fave his rattoons from the
grub ought therefore to cut off the heads of his ftools
with (harp hoes three inches below the furface of the
foil, and then drew an handful of fait round each ftool,
and cover it up to a level with fine mould taken from the
edges.
In foils Yvhere there is no grub, and the planter whil¬
es to have veiy good rattoons, let him, as foon as his
canes are cut, -draw all the trafti from the ftools into the
alternate fpaces, if planted in that manner j or into the
furrows, if his land be round-ridged j and then cut off
the head of his ftools with (harp hoes, as above direfled.
Experience has ftioiYm the advantage of this pradlice,
and reafon demonftrates the great benefit of the rattoon-
fprouts riling from three inches below the furface, in-
ftead of fuperficial (hoots which come to nothing, and
only ftarve the ftrong fprouts. Befides, the ftubs which
are left upon the ftools after the canes are cut, canker,
and rot the ftools; which is one reafon why good rat¬
toons are uncommon in foils long cultivated. Yet it is
the opinion of fome, that by hoe-ploughing and even
dunging rattoons, the produce might be as good plant-
canes, rvhich would fave the labour of holing and plant¬
ing fo often as planters commonly do.
Fallowing is of incredible advantage to every foil, not
only by being divided into the minuteft parts, but alfo
by imbibing thofe vegetative powers with which the air
is impregnated by the bountiful hand of Providence,
whenever rain falls. What thofe powers are has been
explained under the articles Agriculture and Plakt ;
and experience evinces, that the tender vegetables of the
earth are invigorated more by the fmalleft (hoYver of
rain, than by all the water which human art can beftowT.
Let it therefore be a conftant maxim of the planter, ne¬
ver to plant his ground until the foil is well melkwed
by fallmving, even though he beftows upon it a due pro¬
portion of dung : we fay a due proportion ; for too much
will force up rank canes, which never yield good fugar $
and though fome advantage may be reaped from the rat¬
toons,
<0 This pernicious infett is moft apt to engender in dung made from mill-trafh, which therefore never ought to
be put into dung-compoft or ftill-ponds *, but after being burnt, the allies will be as good as any other kind. Round-
ridging, with manure ‘T unwet allies, fea-fand, or lime, or dry marie, kills the grub.
2
Pianter-
Ciip.
P L A
toons, yet it will be found by experience not to com-
penfate the lofs by the plants. In ftony or fteep foils,
where the plough cannot be ufed, or wdrere a fufficient
ftrength of cattle cannot be fupported for that purpofe,
hand-labour or hoe-ploughing mull be fubftituted : but
even in that cafe, much labour may be faved by fpread-
ing the dung according to the Englilh hulbandry, and
digging it into the foil. To evince this truth, let any
planter compute his negroes labour of diftributing dung
by balkets, and by fpreading it w'ith dung-forks; and
then judge for himfelf by one Tingle experiment which is
the moll profitable.
But if fome planters are fo devoted to the old cuftom
of diftributing dung by balkets inftead of wrheel-barrowTs
in level ground, or hand-barrows in uneven land, by
which three times the labour may be accomplilhed in
the fame time and by the fame hands; let them at leaft
feve much of their hand-labour, by the following me¬
thod of laying out dung, before the diftribution by
balkets.
In holing a piece of land, let a fpace be left after 80
holes from the firft interval, and then the like fpace af¬
ter 80 holes throughout the w'hole plat, which fpaces
mu ft run exactly parallel to the intervals on the right
and left of the holes. Into thefe fpaces the dung may
be carted, even before it be rotten (d), at the moft lei-
lure times, and covered with mould or cane-tralh, to pre¬
vent exhalation j and in fuch quantity as will fuffice on¬
ly to dung a row of 40 holes, from the point oppofite to
each fide of it. In the intervals at each fide of the cane-
piece, which are parallel to thofe fpaces, there muft be
dung enough carted to manure a row of 40 holes, and
covered in like manner.
By thus placing the dung or gut-mould, it is evident
at the firft fight, that the fartheft diftance cannot be
above 40 holes in diftributing the dung : and in cafe it
be not fufficiently rotten for prefent ufe, it may be dif-
tributed even in dry weather, and covered by the bank ;
which v7ill both prevent its fpirit from exhalation, and
occafion it to rot fooner,. which is no fmall advantage.
Moreover, by being thus laid out at the moft leifure
times, and covered wnth the banks, the dung wrill be
more intimately mixed w7ith the foil, and therefore con¬
tinue to nourifh the plant for a longer time than if laid
as ufual at the bottom of the holes. A farther advan¬
tage of thus diftributing the dung, and covering it, re-
fults from the more expeditious planting the land after
a Ihort or hidden fhower : for the labour of covering the
dung, and uncovering it wdien the land is planted, how¬
ever it may appear in fpeculation, is in prafHce a trifle j
and befides all the other advantages arifing by the diftri¬
bution of dung from the fpaces above defcribed, tin's is
not the leaft, that not a bank is trodden under foot.
But it is evident, that by diftributing the dung with
balkets in the prefent method, the foil is much trampled
Vol. XVI. Part II.
P L A
under foot; and by that means, the very end of hoe-
ploughing, or loofening the foil, is much defeated. In
like manner, by the prefent method of hoe-ploughing,
the fame ill effect is produced j for as the negroes hoe-
plough or dig the foil diredtly lonvard, fo they muft
neceffarily tread the ground as fall as they dig it:
w7hereas by putting the labourers to dig fidewife, no
one puts a foot upon the foil after it is dug; and by lin¬
ing the land before it is hoe-ploughed, each negro may
have an equal lhare to dig. The only difficulty of hoe-
ploughing fidewife is in firft fetting the negroes to that
work j but it may be done without lofs of time when
working in a contiguous field. Whether hoe-ploughing
before or after the land be holed for canes is molt eli¬
gible, experience muft determine 5 but certainly both
operations v7ill be moft effe£tual : and therefore it will
be advifable (e), firft to plough the foil where the land
wrill admit the plough ; and where it will not, to hoe-
plough it wdth or without dung, as requifite ; then let
it lie fallow till perfectly mellowed j then hole and plant
it $ and inftead of weeding in the ufual manner, let the
weeds in all the fpaces be dug into the foil: but as this
is not to be done fo w7ell w7ith the hoe, it is fubmitted to
future experience, whether the dexterous ufe of fpades,
as in England, will not anfwer the purpofe much bet¬
ter, and wTith equal difpatch. But whatever method is
preferred, moft certain it is, that by loofening the foil
in all the fpaces between the young canes after being
come up, their fibres will more eafily expand on every
fide, and acquire more nutrition to invigorate their
growth. But where the planter grudges this labour, by
thinking it needlefs in a rich loofe foil, he may difpatch
more weeding-w7ork by the Dutch hoe than by any
other 5 which being faftened upon the end of a flick, is
puflied forward under the roots of the fmall weeds, in
fuch a manner as to cut them up a little below the fur-
face of the foil, and will do more execution at one fhove
than can be d«ne at three ftrokes of the common hoe :
but there is yet another pradlice of the horfe-hoe plough,
whereby all weeds growing in rows between beans and
peafe, are extirpated with incredible eafe and expedi¬
tion. It is a very Ample machine, drawn by one or tw7o
horfes, confifting of a pair of low' wheels turning upon
a common axis; from wffience two fquare irons are let
down at equal diftances, and triangular hoes made at
the ends, the points of the triangles being placed for-
W'ard, and fo fixed as to cut all wTeeds an inch below7 the
furface, in the fame manner as the Dutch garden-hoe
above-mentioned. By this machine a man and a boy,
with two horfes or mules, w'ill clear perfefUy all the
fpaces of a field of ten acres in twro days, and may be of
admirable ufe in all loofe and dry foils in the fugar-
iflands: for while two horfes or mules draw7 in the fpace
before each other, the wheels pafs on the outfide of each
row of canes, without doing the leaft injury, while the
4 I plough-
[ 617 ]
Pianter-
fhip.
(d) In order to make dung rot the fooner, much labour is beftowed in digging and turning it over by
hoes : but two-thirds of that labour may be faved by the ufe of hay-knives *, fix of which, ufed dexteroufly, will
cut up a pen in lefs time than 60 negroes can do by hoes : but hay-knives cannot be ufed where gritty mould is
employed in pens.
(e) Deep and loofe foils may be ploughed w'ith a fmall ftrength of cattle or mules: but ftifflands in hot cli¬
mates require more ftrength of cattle than can be maintained in the fmall paftures of the planters ; for if thofi;
llrong foils are either too wet or too dry (.as is generally the cafe), ploughing is impra&icable.
P L A [ 618 ] P L A
Planter- plough-holder attends to his bufinefs. In ft ill' foils which
^’P' require draining, neither the horfe-hoe plough nor the
Dutch hoe can be proper} or any other initrument fo
effectual as the fpade ufed in the manner above hinted,
where the Itaple is deep.
But where the Itaple of land is fnallow, care muff be
taken not to dig much below it, according to the uni-
verfal opinion of all the belt waiters, fupported by the
experience of 100 years. Yet feme good planters are
fallen into the contrary practice, and dig up ffiff clay far
below the ftaple. This, Mr Martin fays, v.Tas done in
his own lands, during his abfence, by injndicioufly
ploughing below the ftaple; and fo injured the foil, that
all the arts of culture for many years hardly retrieved its
former fertility. Indeed, where the ftaple is {hallow,
upon a fat clay, the turning up a little of it at a time,
from the bottom of the cane-holes, and mixing it with
rich hot dung, made of marie, or fandy mould, which
may take off its coheftve quality, will in due time, and
by long fallow, convert it into good foil: but if ftiff clay
be turned up, without any fuch mixture, in large quan¬
tities, it wull infallibly difappoint the operator’s hopes :
for though folid clay will moulder, by expofure, to a
feeming fine earth, yet it will return to its primitive ftate
very feon after being wet, and covered from the external
air, if not divided, as above fuggefted.
After all, the common horfe-hoeing plough drawm by
two mules in a line before each other, or the hand-hoe
in common ufe, will anfwer the purpofe very well, where
the lands are planted in Mr Tull’s method } that is, where
the fpaces are equal to the land planted, in the followTkig
manner.
Suppofe fix feet planted in tvro rows of canes, and fix
feet of land left as a fpace unplanted 5 and fo a whole
piece of land, planted in alternate double rows (r), with
equal fpaces, may be hoe-ploughed with eafe, as before
hinted j and that at any time during the growth of canes,
when it is moft convenient to the planter, which is a
confiderable advantage ; and yet it is the leaft of all at¬
tending this method of culture : for, by leaving thefe
fpaces, the canes will have both more air and fun: by
hoe-ploughing them, the roots of each double rowr will
have large room for expanfion, and confequently, by
gaining more nutriment, wfill grow more luxuriantly :
by thefe fpaces the canes may be cleaned from the blaft
with much more eafe and convenience : and will ferve
as proper beds to plant great corn, without the leaft in¬
jury to the canes } as well as to contain the traftr taken
off the land, where, by rotting, and being hoe-plougbed
into the foil, it will wonderfully enrich it, and will fit
it to be planted immediately after the canes in theneigh-
bouring double row’s are cut down. Befides all thefe
admirable advantages of planting the land in alternate
double rows with equal fpaces, the canes, when at full
age, may be eafily ftripped of their trafh, and by that
means the juice rendered fo mature as to yield double
the produce, and much better fugars than unftripped
canes. This method of culture may be recommended
for ail kinds of foil : for as by this practice the rank
luxuriant canes will be more matured, fo the poor foils
will be rendered more fruitful; and as the roots of the
canes which expand into thefe fpaces will be kept moill
by being covered wdth rotten trafli, fo they muft bear
dry -weather much longer in the burning foils. In thofe
low lands which require draining by furrows, the alter¬
nate double rows and fpaces muft be made crofs the
ridges; by which means thofe fpaces,being hoe-plough¬
ed from the centre to the fides, will be always preferved
in a proper ftate of roundnefs. By this method of plant¬
ing, the canes may be fo well ripened as to yield double
the quantity of fugar of canes planted in the clofe man¬
ner ; which faves half the labour of cartage, half the
time of grinding and boiling, and half the fuel, befides
yielding finer fugar.
Yet, how well foever the method of planting in fingle
or double alternate row’s has fucceeded in the loofe and
ftiff foils, experience has ftrowm that it is a wrong prac¬
tice in ftiff lands that are throw’n into round or flat
ridges: for thefe being moft apt to crack, the fun-beams
penetrate foon to the cane-roots, flop their growth, and
have an ill influence upon the fugar. It is therefore ad-
vifable to plant fuch lands full, but in large holes, of 4
feet, by 5 feet towards the banks: after the plant-canes
are cut, to dig out one, and leave two rows Handing,
hoe-ploughing the fpaces after turning all the trafh into
furrows till almoft rotten : for if the trafti is drawm up¬
on the hoe-ploughed Ipaces, they will hardly ever moul¬
der, at leaft not till the trafh is quite rotten. This is
an infallible proof from experience of how little advan¬
tage trafti is to the foil, unlefs it be in great droughts,
to keep out the intenfe fun-beams : for, in all other re-
fpedfts, it prevents that joint operation of the fun and air
in mouldering and fructifying the foil, as has been pro¬
ved by repeated experiments.
But in flat ftiff foils that are properly drained by
round-ridging, no culture prevents cracking fo effeChially
as hoe-ploughing into them a qantity of loofe marie, of
which that of a chocolate or of a yellow colour is beft ;
and it will be ftill much better, by lying upon the land,
in fmall heaps, or in cane-holes, for fome time, to im¬
bibe the vegetative powers of the air before it is inti¬
mately mixed with the foil.
As to the manner of planting canes, the general prac¬
tice of allowing four feet by five to an hole, and two
frefti (g) plants, is found by common experience to be
right and good in alternate rows. But the following
precautions are neceffary to be obferved. Firft, let all
the cane-rows run eaft and weft, that the trade-wind
may pafs freely through them; becaufe air and funftiine
are as conducive to the growth and maturation offugar-
canes as of any other vegetable. Secondly, let not any
acceflion of mould be drawn into hills round the young
canes, except where water ftagnates (h) ; becaufe the
fibres which run horizontally, and near the furface, are
much
Planter.
fliip.
(f) In ftiff lands, the fingle alternate rows of four feet diftance, as preventive of much labour in weeding, arc
found beft ; and alfo yield more fugar by the acre ; and are lefs apt to be affefted by drought.
(g) It is an odd fancy that ftale plants grow beft, when both reafon and experience vouch that the moft fuccu-
lent plants are beft : one good plant in the centre of a large hole is fufficient when the land is full holed.
(h) The ftagnation of water in pools (ufual in ftiff level lands) is the tnoft injurious circumftance attending it;
for
P L A [619
Planter- muck broken and fpoiled by that practice. Thirdly, let th
the fugar-canes be cut at their full maturity : which, in
v a dry loofe foil, is generally at the end of 14 or 15
months after being planted j but in cold clay-foils, not
till 16 or 17 months.' Fourthly, as the cane-rows run
eaft and weft in as proper a direftion as poffible for cart¬
age to the fugar work, fo canes muft be cut the con¬
trary way if the planter expects any great produce from
his rattoons: for by beginning to cut canes at the part
of his field moll remote from the works, the carts can¬
not often pafs over the fame tra£t, and confequently the
cane-ftools cannot be injured, more efpecially if he takes
due care to cut the canes very clofe to their roots j for,
by leaving a long Hub (which mull perifh) the cane-
ftools are much injured. It may be objected to the prac¬
tice of cutting canes tranfverfely to the rows, that
the negroes labour will not be fo equally divided : but
let every man confider both fides of the queftion, and
be determined by his own experience ; and then he wrill
be convinced, that it matters very little which way he
cuts ftraight Handing canes *, but in cafes where the fu¬
gar-canes lean, or are lodged by preceding high winds,
it is a point of great importance to place the labourers
fo as to cut the canes firft at the roots, and then, draw¬
ing them, cut off the tops : for thus by twro ftrokes
each cane wall be cut; and twice the quantity cut in the
fame time, and by the fame hands, more than by cutting
in any other direction. In round-ridged land, it is pro¬
per to cut canes in the fame direction of the ridges,
throwing the tops and tralh into the furrows to render
the cartage eafy, and to preferve the ridges in their
proper form.
It is almoft needlefs to fuggeft the expediency of plan¬
ning the cane-pieces of a plantation in exaft fquares, fo
that the intervals may interfedt at right angles 5 fince
fuch regularity is not only more beautiful, more fiafe in
cafe of accidental fires, and a better difpofition of the
whole for dividing and planting one third or fourth part
of a plantation every year, but alfo much eafier guarded
by a few watchmen : for one of thefe walking in a line
from eaft to W'eft, and the other from north to fouth,
look through every avenue, where the moft fubtle thief
cannot efcape the watchful eye. And if the intervals
furrounding the boundary of a regular plantation be
made 24 feet wide, the proprietor will receive ample re-
compenfe for fo much land, by the fecurity of his canes
from fires kindled in the neighbourhood, and by plant¬
ing all that land in plantain-trees, wdrich may at once
yield food and fhade to the watchmen, who by that
means can have no excufe for abfence from their proper
ftations. But as fuel grow7s very fcarce in moft of our
illands, it is alfo expedient to plant a logwood or flower-
fence in all the boundaries of every plantation, which,
being cut every year, will furnilh good ftore of faggots.
Logwood makes the ftrongeft and quickeft of all fences,
and agrees with every foil: the cuttings make excellent
oven-fiiel.
So much for the general operations of planterfhip, ac¬
cording to the approved directions of Mr Martin. For
1
P L A
particular cultivation of the fugar-canes, the extrac- Planting,
tion of the fugar, and the diftillation of rum, fee the ar-
tides Sugar, and Hum.
PLANTING, in Agriculture and Gardening, is fet-
ting a tree or plant, taken from its proper place, in a
new hole or pit } throwing frefti earth over its root, and
filling up the hole to the level of the furface of the
ground.
The firft thing in planting is to prepare the ground
before the trees or plants are taken out of the earth,
that they may remain out of the ground as ftiort a‘ time
as poflible 5 and the next is, to take up the trees or
plants, in order to their being tranfplanted. In taking
up the trees, carefully dig away the earth round the
roots, fo as to come at their feveral parts to cut them
off; for if they are torn out of the ground without care,
the roots will be broken and bruifed, to the great injury
of the trees. When you have taken them up, the next
thing is to prepare them for planting by pruning the
roots and heads. And firft, as to the roots j all the
fmall fibres are to be cut off, as near to the place from
whence they are produced as may be, except they are
to be replanted immediately after they are taken up.
Then prune off all the bruifed or broken roots, all fucli
as are irregular and crofs each other, and all downright
roots, efpecially in fruit-trees : thorten the larger roots
in proportion to the age, the ftrength, and nature of
the tree ; obferving that the walnut, mulberry, and
fome other tender-rooted kinds fhould not be pruned fo
clofe as the more hardy forts of fruit and foreft trees :
in young fruit-trees, fuch as pears, apples, plums, peach¬
es, &c. that are one year old from the time of their
budding or grafting, the roots may be left only about
eight or nine inches long ; but in older trees, they muft
be left of a much greater length : but this is only to be
underftood of the larger roots ; for the fmall ones muft
be chiefly cut quite out, or pruned very ftiort. The
next thing is the pruning of their heads, which muft be
differently performed in different trees ; and the defign
of the trees muft alfo be confidered. Thus, if they are
defigned for walls or efpaliers, it is beft to plant them
with the greateft part of their heads, which fhould re¬
main on till they begin to (hoot in the fpring, when they
muft be cut down to five or fix eyes, at the fame time
taking care not to difturb the roots. But if the trees
are defigned for ftandards, you fliould prune off all the
fmall branches clofe to the place where they are produ¬
ced, as alfo the irregular ones which crofs each other;
and after having displaced thefe branches, you fliould
alfo cut off all fuch parts of branches as have by any ac¬
cident been broken or wounded \ but by no means cut
off the main leading (hoots which are neceffary to attract
the fap from the root, and thereby promote the growth
of the tree. Having thus prepared the trees for plant-
ting, you muft now proceed to place them in the earth :
but firft, if the trees have been long out of the ground,
fo that the fibres of the roots are dried, place them eight
or ten hours in water, before they are planted, with
their heads erefl, and the roots only immerfed therein •,
4 I 2 which
for that, by long duration, will convert the fined mould into ftiff clay. The proprietor of fuch a foil muft therefore
grudge no labour to drain it well j and yet by fuch eafy gradation as to prevent the mould from being walked away
by great floods, in cafe the under ftratum be a loam,
P L A [ 620 ] P L A
planting, which will fwell the dried veffels of the roots, and pre-
""—r-*™' pare them to imbibe nourilhment from the earth. In
planting them, great regard fhoula be had to the nature
of the foil : for if that be cold and moift, the trees
fliould be planted very fhallo w •, and if it be a hard rock
or gravel, it will be better to raife a hill of earth where
each tree is to be planted, than to dig into the rock or
gravel, and fill it up with earth, as is too often praftifed,
by which means the trees are planted as it were in a tub,
and have but little room to extend their roots. The
next thing to be obferved is, to place the trees in the
hole in fuch a manner that the roots may be about the
fame depth in the ground as before they were taken up ;
then break the earth fine with a fpade, and fcatter it in¬
to the hole, fo that it may fall in between every root,
that there may be no hollownefs in the earth : then ha¬
ving filled up the hole, gently tread down the earth
with your feet, but do not make it too hard j wThich is
a great fault, efpecially if the ground be ftrong or wet.
Having thus planted the trees, they fhould be faftened
„ to Hakes driven into the ground to prevent, their being
difplaced by the wind, and fome mulch laid upon the
furface of the ground about their roots 5 as to fuch as
are planted againft walls, their roots Ihould be placed
about five or fix inches from the wall, to which their
heads fliould by nailed to prevent their being blown
up by the wind. The feafons for planting are various,
according to the different forts of trees, or the foil in
which they are planted. For the trees whofe leaves fail
off in winter, the beft time is the beginning of Octo¬
ber, provided the foil be dry j but if it be a very wet
foil, it is better to defer it till the latter end of Febru¬
ary, or the beginning of March : and for many kinds
of evergreens, the beginning of April is by far the
beft feafon ; though they may be fafely removed at
midfummer, provided they are not to be carried very
far; but Ihould always make choice of a cloudy wet
feafon.
In the fecond volume of the papers, &c. of the Bath
Society there is a letter on planting wafte grounds. 1 he
gentleman who writes it informs us, that in the county
of Norfolk, -where he refides, there were about 60 or 70
years ago vaft trafts of uncultivated ground, which were
then thought totally barren. “ The we Item parts of it
(fays he) abounded with fand of fo light a texture, that
they were carried about by every wind •, and in many
places the finds were fo loofe that no grafs could grow
upon them. Art and induftry, however, have now fo
altered the face of this once Arabian defert, that it wears
a very different appearance. Moft of thefe tradls are ei¬
ther planted or rendered very good corn-land and ftieep-
walks.
“ About 30 years fince, the fides of many of our little
fand hills were fown with the feeds of French furze, and
when a wet feafon followed, they fucceeded very well,
and grew fo faft, that once in three or four years they
are cut for fuel, and fell at a good price at Thetford,
Brandon, Flarling, Swaffham, and places adjacent.
This excited fome public-fpirited gentlemen, among
whom was the late Mr Buxton of Shadwell-Lodge, near
Thetford, to attempt the planting of Scotch and fpruce
firs, and other hardy foreft trees. At firft they found
fome difficulty from the extreme loofenefs of the fand.
But as there is in all this part of the country fine wdiite
?v;d mellow marie, at about three feet depth belowr the
fand, they very judicioufly thought that incorporating it
with the fand in the holes where their young trees wmre
planted, would infure fuccefs j nor were they difappoint-
ed. The method fucceeded beyond expedlation j the
plantations throve exceedingly, and the roots foon reach¬
ed below the fand, after which they wrere out of danger.
This excited them to further attempts.
“ On the fpots wFere they intended to raife new plan¬
tations from feeds and acorns, they laid on a thick coat
of marie and clay, which after being rough fpread, and
lying a^winter in that ftate, was made fine, and plough¬
ed in juft before planting. By thefe means the foil be¬
came fixed, and in a little time covered wdth grafs and
herbage ; fo that there are now vaft plantations of firs,
oak, and foreft-trees, in the moft: healthy and vigorous
ftate, where within my memory ten acres of land wmuld
not maintain a Angle fheep three months.
“ But the benefit of plantations, whether of Ihrubs,
Planting.
copfe, or trees, is not confined to the immediate advan¬
tage, or even the future value of the wood. By annual¬
ly ftiedding a great number of leaves, which the winds
difperfe, and the rains wafti into the foil, it is confider-
ably improved ; and whenever fuch copfes have been
flubbed up, the grouud (however unfruitful before plant¬
ing) has thereby been fo enriched as to bear excellent
crops for many years, without the additional help of ma¬
nure. How much land-owners are interefted in planting
wafte or barren fpots I need not mention ; and nothing
but a degree of indolence or ignorance unpardonable in
this enlightened age could induce them to negleft it.
“ Nature has fumifhed us with plants, trees, and
fhrubs, adapted to almoft every foil and fituation ; and
as the laws of vegetation are now much better underftood
than formerly, it is a reproach to thofe whofe practice
does not keep pace with their knowledge in making the
belt ufe of her bounty. Let no man repine and fay t/ie
land is barren ; for thofe fpots which appear to be fo,
ow7e that appearance to human negligence. Induftry
and art might foon render an eighth part of this kingdom
nearly as valuable as the reft, which now remains in a
ftate unprofitable to the owners, and difgraceful to the
community.'”
Rev erfe PLANTING, a method of planting in which
the natural pofition of the plant or ftioot is inverted }
the branches being fet into the earth, and the root rear¬
ed into the air. Dr Agricola mentions this monftrous
method of planting, which he found to fucceed very
well in moft or all forts of fruit-trees, timber-trees, &c.
Bradley affirms, that he has feen a lime-tree in Holland
growing with its firft roots in the air, which had fliot
out branches in great plenty, at the fame time that its
firft branches produced roots and fed the tree. Mr Fair-
child of Hoxton has praftifed the fame with us, and
gives the following directions for performing it: Make
choice of a young tree of one ftioot, of alder, elm, wil¬
low, or any other tree that eafily takes root by laying ;
bend the ftioot gently down into the earth, and fo let it
remain until it has taken root. 1 hen dig about the firft
root, and raife it gently out of the ground, till the item
be nearly upright, and flake it up. I hen prune the
roots, now ereCted in the air, from the bruifes and
wounds they received in being dug up ; and anoint the
pruned parts with a compofition of two ounces of tur¬
pentine, four ounces of tallow, and four ounces of bees
wax, melted together, and applied pretty warm. Af¬
terwards
PLA [621] PLA
Planudes, terwards prune off all the buds or flioots that are upon
Plafhing. j|le flera> and drefs the wounds with the fame compofi-
tion, to prevent any collateral Ihootings, that might
fpoil the beauty of the ftem.
PLANUDES, Maximus, a Greek monk of Con-
ftantinople, towards the end of the 14th century, who
publiihed a collection of epigrams intitled Anthologia ; a
Greek tranflation of Ovid’s Metamorphofes 5 a Life of
iEfop, which is rather a romance than a hiftory •, and
fome other works. We know nothing more of him,
than that he fuffered fome perfecution on account of his
attachment to the Latin church.
PLASHING 0/'Hedges, is an operation thought
by fome perfons to promote the growth and continuance
of old hedges} but whether the faft be fo or not will
admit of fome difpute. See Hedges.
It is performed in this manner : The old Hubs muff be
cut oft, &c. within two or three inches of the ground j
and the bell: and longeit of the middle-fized ftioots mult
be left to lay down. Some of the ftrongeit of thefe mull
alfo be left to anfwer the purpofe of Hakes. Thefe are
to be cut off to the height at which the hedge is intend¬
ed to be left; and they are to Hand at ten feet diftance
one from another : when there are not proper ihoots for
theie at the due diftances, their places muff be fupplied
with common Hakes of dead wood. The hedge is to be
firft thinned, by cutting away all but thofe Ihoots which
are intended to be ufed either as flakes, or the other
Tyork of the plalhing : the ditch is to be cleaned out
with the fpade 5 and it muft be now dug as at firft, with
Hoping fides each way 5 and when there is any cavity on
the bank on which the hedge grows, or the earth has
been w^alhed awray from the roots of the Ihrubs, it is to
be made good by facing it, as they exprefs it, with the
mould dug from the upper part of the ditch : all the reft
of the earth dug out of the ditch is to be laid upon the
top of the bank : and the owner ftiould look carefully
into it that this be done j for the workmen, to fpare
themfelves trouble, are apt to throw as much as they
can upon the face of the bank j wdiich being by this
means overloaded, is foon walhed off into the ditch
again, and a very great part of the work undone ;
whereas what is laid on the top of the bank always re¬
mains there, and makes a good fence of an indifferent
hedge.
In the plafhing the quick, twm extremes are to be
avoided ; thefe are, the laying it too low, and the lay¬
ing it too thick. The latter makes the fap run all into
the flioots, and leaves the plafhes without fufficient nou-
rifhment} which, with the thicknefs of the hedge, fi¬
nally kills them. The other extreme of laying them too
high, is equally to be avoided ; for this carries up all
the nourifliment into the plafhes, and fo makes the fhoots
fmall and wreak at the bottom, and cdnfequently the
hedge thin. This is a common error in the north of
England. The beft hedges made anywdiere in England
are thofe in Hertfordfhire ; for they are plafhed in a
middle wray between the two extremes, and the cattle
are by that prevented both from cropping the young
Ihoots, and from going through 5 and a new and vigo¬
rous hedge foon forms itfelf.
When the fhoot is bent down that is intended to be
plafhed, it muft be cut half way through with the bill :
the cut muft be given Hoping, fomewhat downwards,
and then it is to be wound about the flakes, and after Plafhing-
this its fuperfluous branches are to be cut off as they H
ftand out at the fides of the hedge. If for the firft year , p]atter- ,
or tivo, the field where a new hedge is made can be *
ploughed, it will thrive the better for it) but if the ftubs
are very old, it is beft to cut them quite down, and to
fecure them with good dead hedges on both fides, till
tne fhoots are grown up from them ftrong enough to
plafh ; and wherever void fpaces are feen, new fets are
to be planted to fill them up. A new hedge railed from
fets in the common way, generally requires plafhing in
about eight or nine years after.
PLASSEY, is a grove near the city of Muxadab in
India, famous for a battle fought between the Englifh
under Lord Clive, and the native Hindoos under the
nabob Surajah Dowlah. The Bidtifh army confifted of
about 3 200 men, of whom the Europeans did not ex¬
ceed 900 5 while that of the nabob confifted of 50,000
foot, and 18,000 horfe. Notwithftanding this great
difproportion, however, Lord Clive effeftually routed
the nabob and his forces, with the lofs of three Euro¬
peans and 26 Seapoys killed, and five Europeans and 40
Seapoys wounded. The nabob’s lofs was eftimated at
about 200 men, befides oxen and elephants. See
Clive.
PLAST ER, or Emplaster, in Phar/nacy, an ex¬
ternal application of a harder confiftence than an oint¬
ment ; to be fpread, according to the different circum-
ftances of the wound, place, or patient, either upon li¬
nen or leather.
Plaster, or Plai/ler, in building, a compofition of
lime, fometimes with fand, &c. to parget, or cover
the nudities of a building. See Pargeting and
Stucco.
Plaster of Paris, a preparation of feveral fpecies of
gypfum dug near Mount Martre, a village in the neigh¬
bourhood of Paris; whence the name. See Alabas¬
ter, Gypsum, and Sulphate of Lime, under Che¬
mistry.
The beft fort is hard, white, firming, and marbly j
known by the name p/qfier-Jione or parget of Mount
Martre. It will neither give fire with ftecl, nor fer¬
ment with aquafortis; but very freely and readily cal¬
cines in the fire into a fine plafter, the ufe of which in
building and cafting ftatues is well known.
The method of reprefenting a face truly in plafter of
Paris Is this: The perfon, whofe figure is defigned, is
laid on his back, with any convenient thing to keep off
the hair. Into each noftril is conveyed a conical piece
of ftiff paper, open at both ends, to allow of refpiration.
Thefe tubes being anointed with oil, are fupported by
the hand of an affiftant ; then the face is lightly oiled
over, and the eyes being kept Hurt, alabafter freflr cal¬
cined, and tempered to a thinnifh confiftence with wa¬
ter, is by fpoonfuls nimbly thrown all over the face, till
it lies near the thicknefs of an inch. I his matter grows
fenfibly hot, and in about a quarter of an hour hardens
into a kind of ftony concretion j which being gently
taken off, reprefents, on its concave furface, the minu-
teft part of the original face. In this a head of good,
clay may be moulded, and therein the eyes are to be
opened, and other necefl’ary amendments made. This-
fecond face being anointed with oil, a fecond mould of
calcined alabafter is made, confifting of two parts joined
P L A [ 62
Piafter. length wife along the ridge of the nofe • and herein may
be call:, with the fame matter, a face extremely like the
original.
If finely powdered alabafter, or piafter of Paris, be
put into a bafon over a fire, it will, when hot, aflume
the appearance of a fiuid, by rolling in waves, yielding
to the touch, {teaming, &c. all which properties it again
lofes on the departure of the heat ; and being thrown
upon paper, will not at all wet it, but immediately dif-
cover itfelf to be as motionlefs as before it was fet over
the fire ; whereby it appears, that a heap of fuch little
bodies, as are neither fpherical nor otherwife regularly
fhaped, nor fmall enough to be below tire difcernment
of the eye, may, without fufion, be made fluid, barely
by a fufficiently ftrong and various agitation of the par¬
ticles which compofe it; and moreover lofe its fluidity
immediately upon the ceftation thereof.
Two or three fpoonfuls of burnt alabafter, mixed up
thin with water, in a flrort time coagulate, at the bot¬
tom of a vefiel full of water, into a hard lump, notwith-
ftanding the water that furrounded it. Artificers ob-
ferve, that the coagulating property of burnt alabafter
will be very much impaired or loft, if the powder be
kept too long, efpecially if in the open air, before it is
made ufe of} and when it hath been once tempered with
water, and fuffered to grow hard, they cannot, by any
burning or powdering of it again, make it ferviceable for
their purpofe as before.
This matter, when wrought into vefifels, &c. is ftill
of fo loofe and fpongy a texture, that the air has eafy
paflage through it. Mr Eoyle gives an account, among
his experiments with the air-pump, of his preparing a
tube of this piafter, clofed at one end and open at the
other 5 and on applying the open end to the cement, as
is ufually done with the receivers, it was found utterly
impoflible to exhauft all the air out of it} for frelh air
from without prefi'ed in as fall as the other, or internal
air, was exhaufted,'though the fides of the tube were of
a confiderable thicknefs. A tube of iron was then put
on the engine 5 fo that being filled with water, the tube
of piafter of Paris was covered with it 5 and on ufing
the pump, it w-as immediately feen, that the water paf-
fed through into it as eafily as the air had done, when
that was the ambient fluid. After this, trying it wdth
Venice turpentine inftead of water, the thing fucceeded
very well ; and the tube might be perfectly exhaufted,
and would remain in that ftate feveral hours. After
this, on pouring fome hot oil upon the turpentine, the
cafe was much altered ; for the turpentine melting with
this, that became a thinner fluid, and in this ftate capa¬
ble of pafling like wrater into the pores of the piafter.
On taking away the tube after this, it was remarkable
that the turpentine, which had pervaded and filled its
pores, rendered it tranfparent, in the manner that w7ater
gives tranfparency to that lingular ftone called oculus
mundi. In this manner, the weight of air, under pro¬
per management, wall be capable of making feveral forts
of glues penetrate piafter of Paris ; and not only this,
but baked earth, wood, and all other bodies, porous
enough to admit w-ater on this occafion.
Piafter of Paris is ufed as a manure in Penfylvania, as
wo find mentioned in a letter from a gentleman in that
country inferted in the 5th volume of the Bath Society
Papers, and which wo fliall infert here for the fatisfac-
tion and information of our agricultural readers. “ The
3
2 ] P L A
beft kind is imported from hills in the vicinity of Paris :
Plafler.
it is brought down the Seine, and exported from Havre u
de Grace. I am informed there are large beds of it in
the bay of Fundy, fome of which I have feen nearly as
good as that from France ; neverthelefs feveral cargoes
brought from thence to Philadelphia have been uied
without effedt. It is probable this wras taken from the
top of the ground, and by the influence of the fun and
atmofphere difpoft'effed of the qualities neceffary for the
purpofes of vegetation. The lumps compofed of flat
filming fpecula are preferred to thofe which are formed
of round particles like land : the Ample method of find¬
ing out the quality is to pulverize fome, and put it dry
into an iron pot over the fire, w’hen that wThich is good
will foon boil, and great quantities of the fixed air ef-
cape by ebullition. It is pulverized by firfi putting it
in a fiamping-mill. The finer its pulverization the bet¬
ter, as it will thereby be more generally diffufed.
“ It is bell: to fow it in a wet day. The moft appro¬
ved quantity for grafs is fix bufhels per acre. No art is
required in fowing it more than making the diftribution
as equal as pofiible on the fward of grafs. It operates
altogether as a top manure, and therefore fiiould not be
put on in the fpring until the principal frofts are over
and vegetation hath begun. The general time for fow¬
ing with us is in April, May, June, July, Auguft, and
even as late as September. Its effedfs will generally ap¬
pear in 10 or 15 days; after which the growth of the
grafs wfill be fo great as to produce a large burden at the
end of fix weeks after fowing.
“ It muft be fown on dry land, not fubjecl to be over-
flowm. I have fows it on fand, loam, and clay, and it
is difficult to fay on wffiich it has bell anfwered, although
the effefl is fooner vifible on fand. It has been ufed as
a manure in this ftate for upwards of 12 years. Its du¬
ration may, from the bell information I can colleft, be
eftimated fr©m 7 to 1 2 years 5 for, like other manure,
its continuance very much depends on the nature of the
foil on which it is placed.
“ One of my neighbours fowed fome of his grafs
ground fix years ago, another four years ago j a great
part of my own farm wTas fown in May 1788. We re¬
gularly mow7 two crops, and pafture in autumn ; no ap¬
pearance of failure, the prefent crop being full as good
as any preceding. I have this feafon mowed 50 acres of
red clover, timothy grafs, white clover, &c. which was
plaftered laft May, .luly, and September : many who
faw the grafs eftimated the produce at two tons per acre,
but I calculate the twro crops at three tons. Several
ftripes were left in the different fields without piafter j
thefe were in a meafure unproduflive, being fcarcely
worth mowing. In April 1788, I covered a piece of
grafs land upwards of two inches thick with barn ma¬
nure } in the fame worn-out field I fowed piafter, to
contrail it with the dung. I mowred the dunged and
plaftered land twice laft year and once this *, in every
crop the piafter has produced the moft. You will re¬
member, in all experiments with clover, to mix about
one-third timothy grafs feed 5 it is of great advantage in
ferving as a fupport for the clover ; it very much facili¬
tates the curing of clover, and when cured is a fuperior
fodder. The piafter operates equally as wrell on the
other graffes as on clover. Its effeft is faid to be good
on wheat, if fowrn in the fpring ; but I cannot fay this
from experience. On Indian corn I know its operation
to
P L A [ 623 ] P L A
piafter to be great; we ufe it, at the rate of a table fpoonful for
' II a hill, put in immediately after dreffmg.
Plaftic. <( irrom fome accurate experiments laft year made
' ^ ' and reported to our Agricultural Society, it appears
that nine bufhels of additional corn per acre were pro¬
duced by this method of ufing plafter.”
PLASTERING. See Pargetting.
PLASTIC, denotes a thing endowed with a forma¬
tive power, or a faculty of forming or fathioning a mafs
of matter after the likenefs of a living being. .
PLASTIC-Nature, a certain power by which, as an
inftrument, many philofophers, both ancient and modern,
have fuppofed the great motions in the corporeal wrorld,
and the various proceffes of generation and corruption,
to be perpetually carried on.
Among the philofophers of Greece, fuch a power
was almoft univerfally admitted. It feeras, indeed, to
have been rejected only by the followers of Democritus
and Epicurus, who talk as if they had thought gravity
effcntial to matter, and the fortuitous motion of atoms,
which they held to have been from eternity, the fource
not only of all the regular motions in the univerfe, but
alfo of the organization of all corporeal fyltems, and
even offenfation and intelleBion, in brutes and in men.
It is needlefs to fay, that thofe men, whatever they
might profefs, were in reality atheifts; and Democritus,
it is univerfally known, avowed his atheifm.
The greater part of the philofophers who held the
exigence of a plaftic nature, confidered it not as an
agent An the ftridt fenfe of the word, but merely as an in¬
ftrument in the hand of the Deity ; though even among
them there were fome who held no fuperior power, and
were of courfe as grofs atheifts as Democritus himfelf.
Such was Strata of Lampfacus. This man was origi¬
nally of the peripatetic fchool, over which he prefided
many years, with no fmall degree qf reputation for
learning and eloquence. He was the firft and chief af-
fertor of what has been termed Hylozoic atheifm ; a fy-
ftem which admits of no power fuperior to a certain na¬
tural or plajlic life,, cjfential, ingenerable, and incorrupti¬
ble, inherent in matter, but without fenfe and confciouf-
nefs. That fuch was his dodirine we learn from Cicero,
who makes Velleius the Epicurean fay, “ Nec audiendus
Strata qui Phyfcus appellatur, qui omnem vim divinam
in Natura ft tarn effe cenfet, quae caufas gignendi, augen-
^ra^Deorum minuendive habeat, fed careat omni fenfuThat
lib. i/capT’ Strato in admitting this plaftic principle, differed wide-
13. ly from Democritus, is apparent from the following ac¬
count of him by the fame author: Strato Lampfacenus
negat opera deorum fe uti ad fabricandum mundum,
quaecunque lint docet omnia effe effedta naturce, nec ut
ille, qui afperis, et levibus, et hamatis uncinatifque cor-
poribus concreta hsec effe dicat, interjefta inani; fom-
nia cenfet haec effe Democriti, non docentis fed optan-
| Acad. tjs j p?
«phb8 That the rough and fmooth, and hooked and crook-
lV' 3 ’ ed, atoms of Democritus, were indeed dreams and do¬
tages, is a polition which no man will controvert; but
furely Strato was himfelf as great a dreamer wdien he
made fenfation and intelligence refult from a certain pla¬
ftic or fpermatic life in matter, wdiich is itfelf devoid of
fenfe and confcioufnefs. It is, indeed, inconceivable, to
life the emphatic language of Cudworth, “ how any
one in his fenfes Ihould admit fuch a monftrous paradox
as this, that every atom of duft has in itfelf as .much
wifdom as the greateft politician and moft profound phi- Plaftic.
lofopher, and yet is neither confcious nor intelligent!”
It is to be obferved of Strato likewife, that though
he attributed a certain kind of life to matter, he by
no means allowed of one common life as ruling over
the whole material univerfe. He fuppofed the fevaral
parts of matter to haVe fo many feveral plaftic lives of
their own, and feelns J to have attributed fomething to|
chance in the production and prefervation of the mun- Mofbeim,
dane fyftem. iib.i.cap-V
In denying the exiftence of a God, perpetually di¬
recting his plaftic principle, and in fuppoftng as many
of thefe principles as there are atoms of matter, Strato
deviated far from the doftrine of Ariftotle. The great
founder of the peripatetic fchool, as well as his apoftate
difciple, taught that mundane things are not effected by
fortuitous mechanifm, but by fuch a nature as adts regu¬
larly and artificially for eWr; yet he never confiders this
nature as the higheft principle, or fupreme Numen, but
as fubordinate to a perfedt mind or intellcdt \ and he
exprefsly affirms, that “ mind, together with nature,
formed or faffiioned this univerfe.” He evidently con¬
fiders mind as the principal and intelligent agent, and
nature as the fubfervient and executive inftrument. In¬
deed, we are ftrongly inclined to adopt the opinion of
the learned Moftieim, who thinks that by nature Ari¬
ftotle meant nothing more than that or
animal heat, to wdiich he attributes immortality, and of
which he exprefsly fays § that all things are full. Be § <Sene-
this as it may, he always joins God and nature toge-
ther, and affirms that they do nothing in vain. The [ij. cap. t f
fame dodlrine was taught before him by Plato, who af¬
firms that “ nature, together with reafon, and accord¬
ing to it, orders all things.” It muft not, however, be
concealed, that Plato feems to have attributed intelli¬
gence to the principle by which he fuppofed the world
to be animated j for Chalcidius, commenting on the •
Timaeus |, thus expreffes himfelf: “ Haec eft ilia rationa- J Secft. 53,
bills anima mundi, quae gemina juxta meliorem naturam
veneratione tutelam praebet inferioribus, divinis difpofi-
tionibus obfequens, providentiam nativis impertiens, aeter-
norum fimilitudine propter cognationem beata.”—Apu-
leius too, tells us ||, “ Illam coeleftem animam, fontem ^ De Do£~
animarum omnium, optimam virtutem effe genetricem, ”™tePlat0~
fubferviri etiam Fabricatori Deo, et praefto effe ad omnia
inventa ejus.” Plato pronunciat.
The dodtrine of Plato has been adopted by many
moderns of great eminence both for genius and for learn¬
ing. The celebrated Berkeley bifhop of Cloyne, after
giving the view ©f Plato’s anima mundi, which the rea¬
der will find in our article Motion, N° 10, thus recom¬
mends the ftudy of his philofophy * : “ If that philolo- * Sir is, N°
pher himfelf was notread only, but ftudied alfo with 338.
care, and made his own interpreter, I believe the pre¬
judice that now lies againft him would foon wear off,
or be even converted into high efteem, for thofe exalt¬
ed notions, and fine hints, that fparkle and fliine
throughout his waitings which feem to contain not on¬
ly the moft valuable learning of Athens and Greece, but
alfo a treafure of the moft remote traditions and early
fcience of the eaft.” Cudworth, and the learned author
of Ancient Metaphyfics, are likewife ftrenuous advocates
for the Ariftotelian dodtrine of a plaftic nature diffufed
through the material world •, (fee Metaphysics. N0'
200, 201, 202.): and a notian very fimilar has lately
occurred 1
P L A
[
Pla'ftic. ©ccurred to a writer who does not appear to have bor-
: rowed it either from the Lyceum or tne Academy.
This writer is Mr Young, of whofe achve jub[lance,
and its agency in moving bodies, fome account has been
.riven elfewhere, (fee Motion). As a mere unconfci-
ous agent, immaterial, and, as he expreffes himielt, im-
mental, it bears a ftriking refemblance to the plajhc na¬
ture or vegetable life of Cudworth : but the author holds
it to be not only the principle of motion, but alio the
bafts or fubjlratum of matter itfelf 5 in the production of
which, by certain motions, it may be faid to be more ftrictly
plajlic than the hylarchical principle, or vis gcmtrix, of
any other philofopher with whofe writings we have any
acquaintance. Though this opinion be Angular, yet as
its author is evidently a man who thinks for himielt, un¬
awed by the authority of celebrated names, and as one
great part of the utility of fuch works as ours confifts m
their i’erving as indexes to fcience and literature, we
fliall lay before our readers a ihort abilraft of the ica-
fonings by which Mr Young endeavours to fupport his
hypothefis, and we ihall take the liberty of remarking
upon thofe reafonings as wre proceed. ^
The author, after a ihort introduftion, enters upon his
__ work!, in a chapter intitled, Analyfis of Matter in ge-
on the '<ioL- neral. In that chapter there is little novelty. He treats,
ers and me- as others have done, of primary and fecondary qualities,
chanifm of an(j adheres too cloiely to the language of Locke, wmen
nature. he pays? that « the nature of bodies fignifies the aggre¬
gate of all thofe ideas with which they furniih us, and
by wdiich they are made known.” io lay the belt of it,
this fentence is inaccurately expreiled. An aggregate
of ideas may be occafioned by the impulfe oi bodies on
the organs of fenfe, but the effea of impulfe cannot be
that which impels. We iliould not have made this re¬
mark, which may perhaps be deemed captious, were we
not perfuaded that the vague and inaccurate ufe of terms
is the fource of thofe miifakes into which, we cannot
help thinking, that the very ingenious author has iome-
times fallen. Having juftly obferved, that we know no¬
thing dire&ly of bodies but their qualities, he proceeds
to inveftigate the nature of folidity. .
“ Solidity (he fays) is the quality of body which prin¬
cipally requires our notice. It is that which fills exten-
fion, and which refills other_folids, occupying the place
w'hich it occupies 5 thus making extenfion and figure real,
. . r _   r If tfip
624 ] P L A ^
condary qualities of bodies, or their powers vanoufly to ^
affeft our fenfes, depend on their primary qualities, it is
chiefly on this of iolidity } which is therefore the moll
important of the primary qualities, and that in wdiich the
effence of body is by fome conceived to eonfift. This
idea of folidity has been judged to be incapable of any
analyfis ) but it appears evident to me (continues our
author), that the idea of folidity may be refolved into
another idea, which is that of the power of refilling
within the extenfion of body. Hence it becomes unne-
ceffary, and even inadmiflible, to fuppofe that folidity
in the body is at all a pattern or archetype of our lenfa-
tion.”
That folidity in the body, and we know nothing of
folidity any wdiere elfe, is no pattern of any fenfation of
ours, is indeed moll true, as we have Ihown at large in
another place, (fee METAPHYSICS, N° 44 and 171):
but to reconcile this with what our author afierts imme¬
diately afterwards, that “ folidity is no more in bodies
than colours and flavours are, and that it is equally with
them a fenfation and an ideaf would be a talk to which
our ingenuity is by no means equal. He affirms, in¬
deed, that folidity, as it is faid to be in bodies, is ut¬
terly incomprehenfible , that wre can perfectly compre¬
hend it as a lenfation in ourfelves, but that in bodies
nothing more is required than a powTer of a6li\ e refiilance
to make upon our fenfes thofe impreffions from w nich
We infer the reality of primary and fecondary qualities.
This powrer of refillance, whether it ought to be called
active or paffive, wre apprehend to be that which all
other philofophers have meant by the word fohdity;
and though Locke, wffio ules the words idea and notion
indifcriminately, often talks of the idea of iolidity, wTe
believe our author to be the firft of human beings wffio
has thought of treating fohdity as a fenfation in the
mind.
Though it is wrong to innovate in language, when
writing on fubjedts which require much attention, we
mull, however, acknowledge it to be umvorthy of in¬
quirers after truth to difpute about the proper or impro¬
per ufe of terms, fo long as the meaning of him who
employs them can be eafily difcovered. We Ihall, there¬
fore, follow our author in his endeavours, to afcertain
what this power of refillance is wffiich is commonly
known by the name of folidity. All power he juftly
Plaflic.
Sffer E“cf ~cui^ If the fel hold, to be affive S and having, by an angutnent (,>t
, .a We can only conceive of foUdity as being a refinance of the pans of any body, to a power which endea
vours to cZmTthem or to bring them nearer toge'b*- Now that which refifis any power, and prevents its
S isflfo a powen By refifiance, I mean here an aaive ref,fiance, fuch as an animal can employ againft an
Si HahSpdls aygainfi a load, he draw, it along; butifhe J^r hmfe he is put to a
Hand, and his endeavour is defeated. When any endeavour to change the a°£ee“ fer.
like manner prevented from taking effed, and the parts retain their the fitu«.onjms plam , Lee p e
ved by an active refiftance or power, equivalent to that which was fruitlefsly exerted o ^ ^ ^
Such is our author’s reafoning to prove that matter is efientia y ac ne, a b;i;tv pg n > jpe
tion of its folidity: but does he not here confound fohd.ty with hardnefs " ^
certainly does; Sot water is m the P™PeI c"a “L “ith A and thofe of adamant with difficulty ; but
?tf not becaufe the uZZ™ ImMdity than W former but becaufe the P-r
afterwards pulling againfl; another horfe. Is it became boc •• r nfiron of half a ton weight >
the other, and becaufe the load is inaclive that either of them may drag along a mafs of iron oi halt 0
4
P L A [ 625 ] FLA
Pf; flic, which we do not perceive the force, attempted to prove
—v—~ that it is by an inward poxver, and not by its inertia,
that one body prevents another from occupying the fame
place with itfelf, he naturally enough infers matter to be
eiTentially aftive. “ But the activity of matter is to be
conlidered in a certain limited fenfe, and its inertnefs is
to be regarded in another limited fenfe ; fo that thefe are
compatible within their refpedtive limits. The adlivity
of body may be conlidered as belonging to the parts of
a compound 5 its inertia as the inertia formed of thofe
parts. The aftions of the parts are everywhere oppofed
to each other, and equal 5 and hence relults the in acti¬
vity of the whole.”
Solidity alone of the primary qualities being po¬
ll tive, and peculiar to bodies, and our author having re-
folved this into action or POWER, it follows, by his
analylis, that the ESSENCE OF BODY is reduced to power
likewife. But, as he properly obferves, power is an
idea of reflection, not acquired by the fenfes, but fug-
gefted by thought. Hence our knowledge of real ex-
itlence in body muft be fuch as is fuggefted to us by our
thoughts exercifed about our fenfations, “ We are
capable of ating and producing changes in appearances j
and this faculty, which we experience to exift in our-
felves, we call power. We are confcious of the exer¬
tion of our own power; and therefore, when we fee
action or CHANGE happen without any exertion of
ours, we refer this to other powers without us, and ne-
ceffarily conclude the power to exit where the change
begins or the aftion is exerted. This powTer, then,
referred to bodies, muft exift in them, or it can exift no
where.”
In two chapters, which might eafily have been com-
preffed into one not fo long as the fhorteft of them, our
author analyzes atom'; or the primary particles of matter,
and ftrenuouily oppofes their impenetrability. He allows
that there are atoms of matter not divifible by any known
force } but as thefe, however final], muft ftill be concei¬
ved as having extenfion, each of them muft be compo-
fed of parts held together by the fame power which
binds together many atoms in the fame body. This
power, indeed, he acknowledges to operate much more
forcibly when it cements the parts of a primary atom
than when it makes many atoms cohere in one mafs;
but ftill it operates in the fame manner : and as the ideal
analyfis may be carried on ad infinitum, the only pofitive
idea which is fuggefted by atoms, or the parts ox atoms,
is the idea of a refilling power. That this power of re-
fiftance, which conftitutes what is vulgarly called the
felidity of bodies, may not be abfolutely impenetrable,
he attempts to prove, by fhowing that refiftance does in
fa£t take place in cafes -where impenetrability, and even
folidity, are not funpofed by any man.
“ Let us endeavour (fays he) to bring together two
like poles of a magnet, and we {hall experience a re¬
fiftance to their approximation. Why, then, may not
a piece of iron, which between our fingers refifts their
coming together, refill; by an efficacy perfectly fimilar,
though more ftrongly exei'ted ? If magnetifm were to adl
upon our bodies as upon iron, we ihould feel it \ or were
Vol. XVI. Part II.
magnets endowed with fenfation, they would feel that PJaftic.
which refifts their nearer apprQach. The refilling ex- v r"'
tenfion between the two magnets is permeable to all the
rays of light, and refledling none is therefore unfeen j
but it is eafy to conceive that the fame pow'er which re¬
fifts the approach of the iron might refill and refledl fome
rays of light. We Ihould then have a vilible object in-
terpofed between the two magnets, as wre have before
fuppofed it might be a tangible one. It is likev/ife eafy
to conceive that which is tangible and vifible fo applied
to our organs of tailing, of fmelling, and of hearing, as
to excite ideas of flavours, odours, and founds. Thus
we fee that an aftion, in which no fuppofition of folidity
or impenetrability is involved, may be conceived to af-
fume all the qualities of matter, by only fuppofing a fa¬
miliar effedl extended in its operation.”
This reafoning is exceedingly ingenious, though per¬
haps not original •, but what is of more importance,
it does not approach fo near to demonftration as the au¬
thor feems to imagine. If magnets operate by means
of a fluid iffuing from them (fee Magnetism), thofe
who hold the folidity or impenetrability of matter will
maintain, that each atom of the magnetic fluid is
folid and impenetrable. That we do not fee nor feel
thefe atoms, will be confidered as no argument that
they do not exift ; for we do not fee, nor in a clofe room
feel, the atoms of the furrounding atmofphere; 'which
yet Mr Young will acknowledge to have a real exiftence,
and to be capable of operating upon our fenfes of hear¬
ing and fmelling. Let us, however, fuppofe, that by this
reafoning he has eftablifhed the non-exiftence of every
thing in the primary atoms of matter but a£tive powers
of refiftance, and let us fee how he conceives the aflions
of theie powers to conftitute what gives us the notion of
inert and folid body •, for that we have fuch a notion can¬
not be denied.
To act he allows to be an attribute, and juftly ob¬
ferves, that we cannot conceive an attribute to exift
without a fubftance. “ But (fays he) we have traced
all phenomena to a£tion as to a generic idea, compre¬
hending under it all forms of matter and motion as fpe-
cies of that genus. By this analyfis, that complex idea
we have ufually denominated matter, and confidered as
the fubftance or fubftratum to which motion appertained
as an attribute, is found to change its charafter, and to
be itfelf an attribute of a fubftance effentially aftive, of
which one modification of motion produces matter and
another generates motion.” The a£tion of this fubftance
Mr Young determines to be motion, (fee Motion,
N° 16.) ", and he proceeds to inquire by what kind
of motion it produces matter, or inert and refifting
atoms.
“ Whatever portion of the ACTIVE SUBSTANCE is
given to form an atom, the following things are necef-
fary to be united in fuch portion of adlive fubftance ;
\Jl, It muft in fome refpedl continually move-, for
otherwife it would lofe its nature, and ceafe to be ac¬
tive. idly. It muft alfo in fome other refpedl be at
reft, for otherwife it could not form an inactive atom.
3^/y, It muft preferve unity within itfelf.” The author’s
4 K proof
If fo, double or triple the mafs, and a very ftrange phenomenon will be the refult; for we (hall have an adlhve
whole compounded ox two or three inaclive parts, even though thofe parts ftiould not be in contact!
P L A [ 626 ] P L A
Plafhc. proof of the firft of thefe pofitions we have given elfe-
" where. The fecond he holds to be felf-evident; and the
third he thinks ellablilhed by the following reafoning :
“ Solidity is the refult of thofe aflions among the parts
of any whole, whereby the unity of the whole is preferved
within itfelf. Several uncohering things may be united
by an external bond : this does not conftitute thefe one
lolid ■, it may be one bundle : but if feveral things co¬
here, and have a unity preferved within themfelves, they
become one folid. An atom is the lead: and mod fim-
ple folid.”
Having thus proved the neceflity of thefe three re-
quintes to the formation of an atom, he obferves, that
“ the two fird can only be united in a rotation of the
portion of active fubdance about a centre or axis at red.
.By fuch a motion, all the parts fuccedively occupy dif¬
ferent places in the orbit of rotation, and therefore move \
the centre round which they revolve being at red, the
whole portion is alfo at red 5 and thus the portion is at
once moving and quiefcent, as is required. The fame
kind of motion will alfo fulfil the terms of the third re-
quifite; for a fubdance having a revolving motion
around its own centre, preferves its unity by reafon of
all the parts preferving the fame relation to the centre :
and further, a motion of the a£!ive fubdance about a
centre or axis will be an aftivity in the fame orbit, which
will aft upon and refid whatever diall interfere to oppofe
its aftivity, or dedroy the unity of the fphere, by di¬
verting the courfe of the revolving motions. The ac¬
tivity or motion of a portion of active substance about
a centre will, therefore, give folidity to fuch portion ;
for it will give it unity and refidance, and in a manner
tie together all the parts, forming them into one mafs
about their common centre: for they move or are aftive
not towards the centre, in which cafe they would be
lod in non-extenfion j nor from the centre, where they
v'ould diffipate in boundlefs fpace ; but about the centre,
preferving the fame limits of extenfion : and being in this
way aftive, they in this way reild any other aftivity op-
pofed to them, that is, they refid any aftion which tends
to penetrate or divide this fphere of revolving aftivity.
Therefore, fince any portion of aftive fubdance does, by
revolving about a centre, become an united, refilling,
and quiefcent whole, the fmalled portions of the ac¬
tive substance which have fuch motions will become
atoms, or make the fmalled portions of matter.”
Having thus diown to his owm fatisfaftion how atoms
of matter are formed, he next explains what at fird he
confeffes may have appeared a paradox, “ how the ac¬
tive substance, retaining its own nature and effential
properties, continuing immaterial, unfolid, and aftive,
puts on at the fame time the form of matter, and becomes
material, folid, and inert. A fphere of revolving aftive
fubdance, as it revolves continually about a centre, and
as parts of the fubdance, are confidered as fucceffively
paffing through every point in the orbit 5 confidered
thus in its parts, and in its motions, it is active sub¬
stance, immaterial, and unfolid ; but the whole fphere,
confidered unitically, colleftively, and as quiefcent, is
in this point of view a folid atom, material, and in¬
ert.”
Such is the aftive fubdance of Mr Young, and fuch
his theory of the formation of matter. That he has
not with fervility copied from the ancients, every reader
of his book, who is not an abfolute dranger to Greek
and Roman literature, will readily acknowledge; and Plaftfc.
yet if his theory be well founded, he has difcovered a —v-—
middle fubdance between mind and matter, more pro¬
perly piqflic than Aridotle or Plato, Cudworth or Berke¬
ley, ever conceived. But truth compels us to add, that
to us his theory appears to labour under infuperable ob-
jeftious. That there may be in the univerfe a fubdance
effentially aftive, and at the fame time not intelligent,
is a propofition which we are by no means inclined to
controvert. Various phenomena, both in vegetable and
animal life, lead us to fufpeft that there is fuch a fub¬
dance ; but it does not follow that we are inclined to
adopt our author’s doftrine refpefting the formation of
matter. He conceives his proof, indeed, to be “ in its
nature not at all imperfeft, or to fall fhort of demon-
dration ; and if any one refufe it, he thinks it will be
neceffary for him to fhow, either that the explanation,
od’ered is not fufficient, or that fome other explanation
will ferve equally well.”
To diow that the explanation offered is not fufficient,
will not, we apprehend, be a very arduous talk ; but we
have no inclination to attempt ourfelves another expla¬
nation, becaufe we believe that of the formation of mat¬
ter no other account can be given than that which re-
folves it into the fiat of the Creator. That it cannot be
formed by the motion of an immaterial fubdance in the
manner which our author has very clearly defcribed,
feems to be a truth fo evident as not to admit of proof;
for if motion be, as he defines it, a change of place,
every thing that is moved mud have the quality of ex¬
tenfion. But all the parts of this aftive fubdance which
are given to form an atom, move round a centre, and are
exprefsly faid to occupy fucceffively different places in
the orbit of rotation. Every one of thefe parts, there¬
fore, is an extended being : and fince, according to our
author, folidity is nothing but an aElive power of refifi-
ance, and the parts of this aftive fubdance, in their ro¬
tation round their centre, aB upon 3.nd. refifi whoever
interferes to oppofe their aftivity, it follows that each of
thefe parts is likewife a folid being. But, in the opinion
of Mr Young himfelf, and of all mankind, whatever is
extended and folid is material. This theory, therefore,
exhibits a procefs in which atoms are formed of a fub¬
dance, which, though it is faid to be afiive, immaterial,
and unfolid, appears, when narrowly infpefted, to be
nothing elfe than a colleftion of thofe very atoms of
which the author pretends to explain the formation. Mr
Young, who examines and very freely cenfures fome of
the doftrines of NewTon and others, is to* much a man
of fcience to be offended at us for dating objeftions to
a theory wdiich is quite nexv, to a transformation which
he himfelf acknowdedges may to many “ appear not on¬
ly problematical and difficult to conceive, but wholly
impoffible, and implying contradiftions abfolutely and
for ever irreconcileable.” Whether this be a jud charac¬
ter of it our readers mud determine ; but if we did not
believe the author to be a man of ingenuity, we diould
not have introduced him or his work to their acquain¬
tance.
PLASTIC Art, the art of reprefenting all forts of fi¬
gures by the means of moulds. This term is derived
from the Greek word 3-A«r<x>j, which fignifies the “ art
of forming, modelling, or cading, in a mould.” A mould
in general is a body that is made hollow for that pur-
pofe. The artid makes ufe of it to form figures in
bronze,
P L A [ 627 ] P L A
Plaftic. bronze, lead, gold, filver, or any other metal or fufible
fubftance. The mould is made of clay, ftucco, or other
compofition, and is hollowed into the form of the figure
that is to be produced ; they then apply the jet, which
is a fort of funnel, through which the metal is poured
that is to form the figures, and that is called running the
metal vita the mould.
It is in this manner, but with much praftice and at¬
tention, that the artift forms, 1. Equeftrian and pedef-
trian ftatues of every kind j 2. Groups •, 3. Pedeftals •,
4. Bafs-reliefs; 5. Medallions 5 6. Cannons, mortars, and
other pieces of artillery ; 7. Ornaments of architedlure,
as capitals, bales, &c. ; 8. Various forts of furniture, as
luftres, branches, &c. in every kind of metal: and in
the fame manner figures are calf in ftucco, plalfer, or
any other fulible matter. See PLASTER of Paris.
Wax being a fubllance that is very eafily put in fu-
fion, plaltics make much ufe of it. There are impref-
fions which are highly plealing in coloured wax, of me¬
dallions, baflb and alto relievos, and of detached figures j
y which, however, are fomewhat brittle. But this mat¬
ter has been carried too far: they have not only formed
moulds to reprefent the likenefs and the bull of a living
perfon, by applying the plalter to the face itfelf, and
afterwards calling melted wax into the mould 5 but
they have alfo painted that waxen bull with the natural
colours of the face, and have then applied glafs eyes and
natural hair ; to which they have joined a Huffed body
and limbs, with hands of wax j and have, laflly, dreffed
their figure in a real habit; and by thefe means have
produced an objedl the moll fhocking and detellable
that it is poffible to conceive. It is not a llatue, a bull,
a natural refemblance that they form ; but a dead body,
a lifelefs countenance, a mere carcafe. The lliff air, the
inflexible mufcles, the haggard eyes of glafs, all contri¬
bute to produce an objedl that is hideous and difgullful
to every man of talle. , Figures like thefe offend by
affording too exacl an imitation of nature. In no one
of the polite arts ought imitation ever to approach fo
near the truth as to be taken for nature herfelf. Illu-
fion mull have its bounds j without which it becomes
ridiculous.
There is another invention far more ingenious and
pleafing, which is that wherein M. Lippart, antiquary
and artill at Drefden, has fo much excelled. He has
found the means of refembling, by indefatigable labour,
great expence, and infinite talle, that immenfe number
of Hones, engraved . and in camaieu, which are to be
feen in the moff celebrated cabinets. He has made
choice of thofe that are the moff beautiful •, and, with a
paffe of his own invention, he takes from thefe Hones an
impreflion that is furprifingly accurate, and which after¬
wards become as marble : thefe impreffions he calls pajli.
He then gives them a proper colour, and inclofes each
with a gold rim •, and, by ranging them in a judicious
order, forms of them an admirable fyffem. They are
fixed on paffeboards, which form fo many drawers, and
are then inclofed in cafes, which reprefent folio volumes,
and have titles wrote on their backs 5 fo that thefe fic¬
titious books may conveniently occupy a place in a li¬
brary. Nothing can be more ingenious than this in¬
vention ; and, by means of it, perfons of moderate for¬
tune are enabled to make a complete colle£lion of all
antiquity has left that is excellent of this kind ; and the
copies are very little inferior to the originals.
There is alfo another method of taking the impref¬
fions of camaieus, medals, and coins, which is as fol¬
lows : They waih or properly clean the piece whole im-
prefiion is to be taken, and furround it with a border of
wax. They then diffolve ifinglals in water, and make
a decodlion of it, mixing with it fome vermilion, to give
it an agreeable red colour. They pour this paffe, when
hot, on the ftone or medal, to the thicknefs of about the
tenth part of an inch 5 they then leave it expofed to the
fun, in a place free from duff. After a few days this
pafte becomes hard, and offers to the eye the molt ad¬
mirable and faithful reprefentation of the medal that it
is poflible to conceive : they are then carefully placed
in drawers j and thoufands of thefe impreflions, which
comprehend many ages, may be included in a fmall
compafs.
The proficients in plaftics have likewife invented the
art of calling in a mould papier mache or diffolved paper,
and forming it into figures in imitation of fculpture, of
ornaments and decorations for ceilings, furniture, &c.
and which they afterwards paint or gild. There are,
however, fome inconveniences attending this art; as, for
example, the imperfedlions in the moulds, which render
the contours of the figures inelegant, and give them a
heavy air : thefe ornaments, moreover, are not fo dur¬
able as thofe of bronze or wood, feeing that in a few
years they are preyed on by the worm.
The figures that are given to porcelain, Delft ware,
&c. belong alfo to plaftics ; for they are formed by
moulds, as well as by the art of the fculptor and turner j
and by all thefe arts united are made vafes of every
kind, figures, groups, and other defigns, either for ufe of
ornament.
From this general article the reader is referred to
Foundery, Cast, Glazing, Porcelain, Papier-
Mache, Pottery, Delft Ware.
PLATA, the name of a very great river of South
America, running through the province of Paraguay j
whence the whole country, is fometimes called Plata;
though this name is ufually beftowed only upon a part
of Paraguay. In the latter fenfe it comprehends all
that country bounded on the eaft and fouth-eaft by the
Atlantic ocean j on the fouth, by Tena Magellanica j
on the weft, by Tucuman 5 and 'on the north, by the
provinces of Paraguay Proper and Parana. The great
river La Plata, from which the country has its name,
was firft difeovered, in 1515, by Juan Diaz de Solis;
but denominated La Plata by Sebaftian Gabato, from
the great quantity of the precious metals he procured
from the adjacent inhabitants, imagining it was the pro¬
duce of the country, though in fa61 they brought it from
Peru.
The country lies between 3 2° and 370 of fouth la¬
titude. The climate is pleafant and healthy. Their
winter is in May, June, and July, when the nights are
indeed very cold, but the vdays moderately warm ; the
froft is neither violent nor lafting, and the fnows are ve¬
ry inconfiderable.
The country confifts moftly of plains of a vaft ex¬
tent, and exceeding rich foil, producing all forts of Eu¬
ropean and American fruits, wheat, maize, cotton, fu-
gar, honey, &c. and abounding with fuch excellent pa~
ftures, that the beaffs brought hither from Spain are
multiplied to fuch a degree, that they are all in com¬
mon, no man claiming any property in them, but every
4 K 2 man
P L A [ 628 ] P L A
Plata, man takes what he hath occafion for. The number of
Platceae. black cattle, efpecially, is fo prodigious, that many ihou-
v fands of them are killed merely lor their hides, every
time the ftiips go for Spain, and their carcafes left to
be devoured by wild hearts and birds of prey, which are
alfo very numerous. Sometimes, when they cannot
vend their hides, they will kill them for their tongues 5
and thofe who care not to be at the trouble to fetch
them from the plains, may buy them for a trifle. There
is a curious account in Lord Anfon’s voyage of the
manner of hunting them on horfeback 5 and of catching
and killing them, by throwing a noofe on their horns at
full gallop, the horles being trained to the fport. Horfes
are no lefs numerous, and in common like the other
cattle •, fo that a man may have as many as he pleafes
for the catching *, and of thole that are already broke,
one may buy fome of the beft, and of the true Spanilh
breed, for a piece-of-eight per head. Wild-fowl alfo is
in great plenty here 5 partridges in particular are more
numerous, and as large and tame as our hens, fo that
one may kill them with a flick. Their wheat makes
the finefl and white ft of bread •, and, in a word, they
feem tti wrant for nothing here, efpecially the natives,
but fait and fuel. The former the Spaniards have
brought to them from other parts 5 and the latter they
fupply themfelves with, by planting vaft numbers of al-
(fr mond, peach, and other trees, which require no other
> trouble than putting the kernels into the ground, and
by the next year, we are told, they begin to bear fruit.
The return for European commodities is fo great here,
that it almoft exceeds belief 5 an ordinary two penny
knife fetching a crown, and a gun of the value of 10 or
12 (hillings 20 or 30 crowns, and fo of the reft.
The river Plata riles in Peru, and receives a great
many others in its courfe; the chief of which is the
Paraguay. The water of it is faid to be very clear and
fwcet, and to petrify wood ; and contains fuch plenty
and variety of firti, that the people catch great quan¬
tities of them without any other inftrument than their
hands. It runs moftly to the fouth and fouth-eaft 5 and
is navigable the greater part of its courfe by the largeft
velfels, and full of delightful illands. All along its
banks are feen the moft beautiful birds of all kinds •, but
it fometinaes overflows the adjacent country to a great
extent, and is infefted by ferpents of a prodigious big-
nefs. From its junftion with the Paraguay to its mouth
it is above 200 leagues. We may form fome judgement
of its largenefs by the width of its mouth, which is faid
to be about 70 leagues. Before it fhlls into the Para¬
guay it is called Vanama. See Panama.
PL, ATAf/E, in Ancient Geography, a very ftrong
towm of Boeotia, in its lituation expofed to the north
wind (Theophraftus) \ burnt to the ground by Xerxes
(Herodotus, Juftinus) •, mentioned much in the courfe
of the Perfian war : Famous for the defeat of Mardoni-
us, the Perlian general ^ and for the moft fignal vidlory
of the Lacedemonians and other Greeks under Paufanias
the Lacedemonian, and Ariftides an Athenian general
(Nepos, Diodorus, Plutarch) 5 in memory of which the
Greeks eredled a temple to Jupiter Eleutherius, and in-
ftituted games which they called Eleutheria ; and there
they fhow the tombs of thofe who fell in that battle
(Strabo). It flood at the foot of Mount Cithaeron, be¬
tween that and Thebes to the north, on the road to A-
thens and Megara, and on the confines of Attica and Platalea
Megaris. Now in ruins. It
PLATALEA, the Spoonbill, a genus of birds be- ,
longing to the order of grallm. See Ornithology Index.
PLATAN US, the Plane-tree ; a genus of plants
belonging to the monoecia clais. See Botany Index.
PLATBAND, in Gardening, a border or bed of
flowers, along a wall, or the fide of a parterre, frequent¬
ly edged with box', &c.
Platband of a door or window, is ufed for the lin¬
tel, where that is made fquare, or not much marked.
PLATE, a term which denotes a piece of wrought
filver, fuch as the ihallow veffel oft which meat is eaten.
It is likewife ufed by fportfmen to exprefs the reward
given Lo the beft horfe at our races.
The winning a plate is not the work of a few days „
1 P 1 f r 1 1 ‘ oportfman s
to the owner of the horie ; but great care and prepara- j^iclionar^.
tion is to be made for it, if there is any great depen¬
dence on the fuccefs. A month is the leait time that
can be allowed to draw the hoife’s body clear, and to
refine his wind to that degree of perfection that is attain¬
able by art.
It is fir ft necefiary to take an exadf view of his body,
whether he be low or high in flefh ; and it is alfo necef-
fary to confider whether he be dull and heavy, or brifk
and lively when abroad. If he appear dull and heavy,
and there is reafon to fuppofe it is owing to too hard
riding, or, as the jockeys exprefs it, to fome greafe that
has been dilfolved in hunting, and has not been removed
by fcouring, then the proper remedy is half an ounce of
diapente given in a pint of good fack } this will at once
remove the caufe, and revive the creature’s fpirits.
After this, for the firft week of the month, he is to be
fed with oats, bread, and fplit beans; giving him fome-
times the one and fometimes the other as he likes beft j
and always leaving fome in the locker, that he may
feed at leifure when he is left alone. When the groom
returns at the feeding lime, whatever is left of this mull
be removed, and frefn given ; by this means the crea¬
ture will foon become high-fpirited, wanton, and full of
play. Every day he muft be rode out an airing, and
eveiy other day it will be proper to give him a little
more exercife •, but not fo much as to make him iweat
too much. The beans and oats in this cafe are to be
put into a bag, and beaten till the hulls are all off, and
then winnowed clean 5 and the bread, inftead of being
chipped in the common way, is to have the cruft clean
cut off. If the horfe be in good flefh and fpirits when
taken up for its month’s preparation, the diapente muft
be omitted 5 and the chief bufmefs will be to give him
good food, and fo much exercife as will keep him
in wind, without overfweating him or tiring his fpirits.
When he takes larger exercifes afterwards, towards the
end of the month, it will be proper to have fome horfes
in the place to run againft him. This will put him
upon his mettle, and the beating them will give him
fpirits. This, however, is to be cautioufly obferved,
that he has not a bloody heat given him for ten days or
a fortnight before the plate is to be run for; and that
the laft heat that is given him the day before the race,
muff be in his clothes : this will make him run with
greatly more vigour, when ftripped for the race, and
feeling the cold wind on every part.
In the fecond week, the horfe fliould have the fame
food,
Plate
!!
Platina.
Chemistry
P L A [ 629 ]
food, and more exercife. In the lail fortnight, he muft count of its
have dried oats, that have been hulled by beating. Af-
^ ter this they are to be wetted in a quantity of whites of
eggs beaten up, and then laid out in the fun to dry;
and when as dry as before, the horfe is to have them.
•f his fort oi food is very light of digellion, and very
good for the creature’s wind. The beans in this, time
ihould be given more fparingly, and the bread fliould
be made of three parts wheat and one part beans. If
he ihould become coilive under this courfe, he muft then
have fome ale and whites of eggs beaten together ; this
will cool him, and keep his body moift.
In the laft week the math is to be omitted, and bar¬
ley-water given him in its place, every day, till the day
before the race : he Ihould have his fill of hay 5 then he
muft have it given him more fparingly, that he may
have time to digeft it ; and in the morning of the race
day he muft have a Loaft or two of white bread foaked
in lack, and the fame juft before he is let out to the
held. I his is an excellent method, becaufe the two
♦xtremes of fullnefs and failing are at this time to be
equally avoided : the one hurting his wind, and the
other occafioning faintnefs that may make him lofe.
Alter he has bad his food, the litter is to be fhook up,
and. the liable kept quiet, that he may be difturbed by
nothing till be is taken out to run.
PLATFORM, in the military art, an elevation of
earth, on which cannon is placed to fire on the enemy }
fuch are the mounts in the middle of curtins. On the
ramparts there is always a platform, where the cannon
are mounted. It is made by the heaping up of earth
on the rampart, or by an arrangement of madriers, rifing
infenfibly, for the cannon to roll on, either in a cafemate
or on attack in the outworks. All practitioners are
agreed, that no fliot can be depended on, unlefs the
piece can be placed on a folid platform ; for if the plat¬
form fhakes with the firft impulfe of the powTder, the
piece muft likewife {hake, which wull alter its diredlion,
a'nd render the fliot uncertain.
Platform, in Archite&ure, is a row of beams which
fupport the timber-w®ik of a roof, and lie on the top @f
a wall where the entablature ought to be raifed.
This term is alfo ufed for a kind of terrace or broad
fmooth open walk at the top of a building, from whence
a fair profpeft may be taken of the adjacent country.
Hence an edifice is faid to be covered with a platform,
when it is flat at top, and has no ridge. Moft of the
oriental buildings are thus covered, as were all thofe of
the ancients.
Platform, or Orlop, in a man of war, a place on
the lower deck, abaft the main-maft, between it and
the cockpit, and round about the main eapftan, where
provifion is made for the wounded men in time of aCHon.
PLATINA is a metallic fubftance, the name of
which has an allufion to its colour. It is a diminutive
plata, and fignifies “ little filver.” From its great
fpecific gravity, and other refemblances which it has to
gold, it has been called or blanc, or white gold; from
its refractory nature, diabolus metallorum; from fome
doubts entertained of its chara&er as a metal, juan
bianco, white jack, white rogue, or white mock metal.
It has alfo received the appellation of the eighth metal:
and, probably from fome diftridl which affords it, has
gotten the name of platina del Pinto. For an ac-
P L , A
properties, and for its natural liiftory, fee
, Mineralogy ; and Ores, ReduElion of.
PLATING is the art of covering baler metals with
a thin plate of filver either for ufe or for ornament. It
is faid to have been invented by a fpur-maker, not for
fhow but for real utility. Till then the more elegant
fpurs in common ufe were made of folid filver, and from
the flexibility of that metal they were liable to be bent
into inconvenient forms by the flighteft accident. To
remedy tins defect, a workman at Birmingham contri¬
ved to make the branches of a pair of fpurs hollow, and
to fill that hollow with a flender rod of fteel or iron.
Finding this a great improvement, and being defirous
to add cheapness to utility, he continued to make the
hollow larger, and of courfe the iron thicker and
thicker, till at laft he difeovered the means of coating
an iron fpur with filver in fuch a manner as to make it
equally elegant with thofe which were made wholly of
that metal. The invention was quickly applied to
other purpofes ; and to numberlefs utenfils which were
formerly made of bi afs or iron are now given the ftrength
of thele metals, and the elegance of filver, for a fmall ad¬
ditional expence.
The filver plate is generally made to adhere to the
bafer metal by means of folder 5 which is of tw'o kinds,
the fft and the hard, or the tin and filver folders. The
former of thefe confifts of tin alone, the latter ge¬
nerally of three parts of filver and one of brafs. When
a buckle, for inftance, is to be plated by means of the
foft folder, the ring, before it is bent, is firft tinned,
an4 then the filver-plate is gently hammered upon it,
the hammer employed being always covered with a
piece of cloth. The filver now forms, as it were, a
mould to the ring, and whatever of it is not intended
to be ufed is cut off. This mould is faftened to the
ring of the buckle by two or three cramps of fmall iron-
wire ; after which the buckle, with the plated fide
undermoft, is laid upon a plate of iron fufficiently hot
to melt the tin, but not the filver. The buckle is then
covered with powdered refin or anointed with turpen¬
tine ; and left there fhould be a deficiency of tin, a
fmall portion of rolled tin is likewife melted on it. The
buckle is now taken off with a tongs, and commonly
laid on a bed of fand, where the plate and the ring,
while the folder is yet in a ftate of fufion, are more
clofely compreffed by a fmart ftroke with a block of
wroed. The buckle is afterwards bent and finifhed.
Sometimes the melted tin is poured into the filver
mould, which has been previoufly rubbed over with
fome flux. The buckle ring is then put among the
melted tin, and the plating finifhed. This is called by
the workmen filling up.
When the hard folder is employed, the procefs is in
many refpe&s different. Before the plate is fitted to
the iron or other metal, it is rubbed over with a iblu-
tion ©f borax. Stripes of filver are placed along the
joinings of the plate ; and inftead of tw'o or three
cramps, as in the former cafe, the whole is wrapped
round with fmall wire j the folder and joinings are again
rubbed with the borax, and the whole put into a char¬
coal fire till the folder be in fufion. When taken out,
the wire is inftantly removed, the plate is cleaned by
the application of fome acid, and afterwards made
fmooth by the.ftrokes of a hammer.
Me tali
Plating:
Plating,
Plato.
P , L A [63
Metal plating is when a bar of filver and copper are
taken of at leail one equal fide. The equal fides are
made fmooth, and the two bars fattened together by
wire wrapped round them, i hefe bars are tnen Iweated
in a charcoal fire, and after fweating, they adhere as
clofely together as it they were foldeied. dkftei this
they are flattened into a plate between two rollers, when
the copper appears on one fide and the filver on the
other. This fort of plate is named plated metal.
French plating is when filver-leaf is burnifhed on a
piece of metal in a ce-tain degree of heat.
When filver is diffolved in aquafortis, and precipita¬
ted upon another metal, the procefs is called Jilverwg.
See Soldering.
PLATO, an illuftrious philofopher of antiquity, was
by defcent an Athenian, though tne place ol his birth
was the ifland of Egina. His lineage through his fa¬
ther is traced back to Codrus the laft king of Athens,
and through his mother to bolon the celebrated legifia-
tor. The”time of his birth is commonly placed in the
beginning of the 88th Olympiad j but Dr Enfield thinks
it may be more accurately fixed in the third year of the
87th Olympiad, or 430 years before the Chriftian era.
He gave early indications of an extenfive and original
genius, and had an education fuitable to his high rank,
being inftrufted in the rudiments of letters by the gram¬
marian Dionyfius, and trained in athletic exercifes by
Arifto of Argos. He applied with great diligence to
the ftudy of the arts of painting and poetry ; and made
fuch proficiency in the latter, as to produce an epic poem,
v/hich, upon comparing it with the poems of Homer,
he committed to the flames. At the age of 20 he com-
pofed a dramatic piece ; but after he had given it to the
performers, happening to attend upon a ducoutle of So¬
crates, he was fo captivated by his eloquence, that he
reclaimed his tragedy without fuffering it to be a&ed,
renounced the mufes, burnt all his poems, and applied
himfelf wholly to the ftudy of wifdom.
It is thought that Plato’s firft mailers in philofophy
Were Cratylus and Hermogenes, who taught the fyftems
of Heraclitus and Parmenides ; but when he was 20
years old, he attached himfelf wholly to Socrates, with
whom he remained eight years in the relation of a fcholar.
During this period, he frequently difpleafed his compa¬
nions, and fometimes even his matter, by grafting up¬
on the Socratic fyftem opinions which were taken from
fome other ftock. It wTas the practice of the fcholars of
Socrates to commit to writing the fubftance of their
matter’s difcourfes. Plato wrote them in the form of
dialogues 5 but with lo great additions ot ms ow n, that
Socrates, hearing him recite his Lyfis, cried out, ‘‘ O
Hercules ! how many things does this young man feign
of me !”
Plato, however, retained the warmeft attachment to
his matter. When that great and good man was fum-
moned before the fenate, his illuftrious fcholar under¬
took to plead his caufe, and begun a fpeech in his de¬
fence ; but the partiality and violence of the judges
would not permit him to proceed. After the condem¬
nation, he prefented his matter with money fufficient to
redeem his life ; which, however, Socrates refufed to ac¬
cept. During his imprifonment, Plato attended him,
and was prefent at a converfation which he held with
his friends concerning the immortality of the foul j the
o ] P L A
fubftance of which he afterwards committed id writing
in the beautiful dialogue intitled Phctdo, not, hcwevef,
without interweaving his own opinions and language.
The philofophers who were at Athens were 10 alarm¬
ed at the death of Socrates, that moft of them fled nom
the city to avoid the injuftice and ciuelty of t’ae g ♦ ;
ment. Plato, whofe grief upon this occalion is laid by
Plutarch to have been exceflive, retired to Megaraj where
he was kindly entertained by Euclid, who had been one
of Socrates’s firft fcholars, till the ftorm was over. Af¬
terwards he determined to travel in purfuit of knowledge j
and from Megara he went to Italy, where he conferred
with Eurytus, Philolaus,. and Archytas. Thefe w7ere
the moft celebrated of the followers of Pythagoras,
whofe doftrine was then become famous in Greece 5 and
from thefe the Pythagoreans have affirmed that he had
all his natural philofophy. He dived into the moft pro¬
found and myfterious fecrets of the Pythagonc dodlrines j
and perceiving other knowledge to be connefted with
them, he went to Gyrene, where he learned geometry
of Theodorus the mathematician. From thence he pai-
fed into Egypt, to acquaint himfelf with the theology of
their priefts, to ftudy more nicely the proportions of geo¬
metry, and to inftruft himfelf in aftronomical obferva-
tions j and having taken a full furvey of all the country,
he fettled for fome time in the province of Sais, learning
of the wife men there, w hat they held concerning the
univerfe, wffiether it had a beginning, whether it moved
wffiolly or in part, &c. j and Paufanias affirms, that he
learned from thefe the immortality, and alfo the tranf-
migration, of fouls. Some of the fathers wall have it,
that he had communication wfilh the books of Mofes,
and that he ftudied under a learned Jew7 of Heliopolis j
but there is nothing that can be called evidence for thefe
affertions. St Auftin once believed that Plato had
fome conference wfith Jeremiah j but afterwards difcover-
ed, that that prophet mutt have been dead at leaft 60
years before Plato’s voyage to Egypt.
Plato’s curiofity w7as not yet fatisfied. He travelled
into Perfia to confult the magi about the religion of
that country : and he defigned to have penetrated even
to the Indies, and to have learned of the Brachmans their
manners and cuftoms j but the w’ars in Afia prevented him.
“ He then returned into Italy, to the Pythagorean
fchool at Tarentum, where he endeavoured to improve
his own fyftem, by incorporating with it the doftrine of
Pythagoras, as it was then taught by Archytas, Timaeus,
and others. And afterwards, when he vifited Sicily, he
retained fuch an attachment to the Italic fchool, that,
through the bounty of Dionyfius, he purchafed at a vaft
price feveral books which contained the do&rine of Py¬
thagoras, from Philolaus, one of his followers.
“ Returning home richly ftored with knowledge of va¬
rious kinds, Plato fettled in Athens, and. executed the
defign, which he had doubtlefs long had in contempla¬
tion, of forming a new fchool for the inftrudlion of youth
in the principles of philofophy. 'I he place which he
made choice of for this purpofe w7as a public grove, call¬
ed the Academy, from Hecademus, who left it to the
citizens for the purpofe of gymnaftic exercifes. Adorned
with ftatues, temples, and fepulchres, planted with lofty
plane-trees, and interfered by a gentle ftream, it afforded
a delightful retreat for philofophy and the mufes. Of
this retreat Horace fpeaks:
Atque
Plato.
3
P L A
[ 631 ] P L A
-Plato.
—'v—“J Atque inter fylvas Academi qucerere verum.
“ ’Midft Academic groves to fearcli for truth.”
Within this inclofure he poffelfed, as a part of his humble
patrimony, purchafed at the price of three thoufand
drachmas, a fmall garden, in which he opened a fchool
for the reception of thofe who might be inclined to at¬
tend his inftruftions. How much Plato valued mathe¬
matical ftudies, and how neceffary a preparation he
thought them for higher fpeculations, appears from the
infcription which he placed over the door of his fchool:
«ys*) IrgtjToj uzhtm. Let no one w'ho is unac¬
quainted with geometry enter here.”
“ This new ichool foon became famous, and its mailer
was ranked among the moil eminent philofophers. His
travels into diftant countries, where learning and wifdom
flouriihed, gave him celebrity among his brethren of the
Socratic fe£l. None of thefe had ventured to inftitute
a fchool in Athens except Ariilippus •, and he had con¬
fined his inftructions almoft entirely to ethical fubjedts,
and had brought himfelf into fome difcredit by the free¬
dom of his manners. Plato alone remained to inherit
the patrimony of public efteem which Socrates had
left his difciples ; and he poflefled talents and learning
adequate to his defign of extending the iludy of philo-
fophy beyond the limits within which it had been in-
clofed by his mafter. The confequence was, not only
that young men crowded to his fchool from every quar¬
ter, but that people of the firft diilindtion in every de¬
partment frequented the academy. Even females, dif-
guifed in men’s clothes, often attended his ledlures. A-
mong the illuftrious names which appear in the cata¬
logue of his followers are Dion the Syracufan prince,
and the orators Hyperides, Lycurgus, Demofthenes, and
Ifocrates.
“ Greatnefs was never yet exempted from envy. The
diftinguilhed reputation of Plato brought upon him the
hatred of his former companions in the fchool of So¬
crates, and they loaded him with detraflion and oblo¬
quy. It can only be afcribed to mutual jealoufy, that
Xenophon and he, though they relate the difcourfes of
their common mafter, ftudioufly avoid mentioning one
another. Diogenes the Cynic ridiculed Plato’s doc¬
trine of ideas and other abftradl fpeculations. . In the
midft of thefe private cenfures, however, the public fame
of Plato daily increafed j and feveral ftates, among which
were the Arcadians and Thebans, fent ambaffadors with
earneft requefts that he would come over, not only to in-
ftrufl the young men in philofophy, but alfo to prefcribe
them laws of government. The Cyrenians, Syracufans,
Cretans, and Eleans, fent alfo to him : he did not go to
any of them, but gave laws and rules of governing to all.
Pie lived Angle, yet foberly and chaftely. He was.a man
of great virtues, and exceedingly affable } of which we
need no greater proof, than his civil manner of converfing
with the philofophers of his own times, when pride and
envy were at their height. His behaviour to Diogenes is
always mentioned in his hiftory. The Cynic was vaftly
offended, it feems, at the politenefs and fine tafte of Plato,
and ufed to catch all opportunities of fnarling at him. He
dined one day at his table with other company, and, tram¬
pling upon the tapeftry with his dirty feet, uttered this
brutifti farcafm, “ I trample upon the pride of Plato 5” to
which Plato wifely reparteed, “ With greater pride.”
The fame of Plato drew difciples to him from all parts $ Plato,
among whom were Speufippus an Athenian, his fifter’s y-“
fon, whom he appointed his fucceffor in the academy,
and the great Ariftotle.
The admiration of this illuftrious man was not con¬
fined to the breafts of a few philofophers. He was in
high efteem with feveral princes, particularly Archelaus
king of Macedon, and Dionyfius tyrant of Sicily. At
three different periods he viiited the court of this latter
prince, and made feveral bold but unfuccefsful attempts
to fubdue his haughty and tyrannical fpirit. A brief
relation of the particulars of thefe vifits to Sicily may
ferve to calf fome light upon the character of our phi-
lofopher j and we fhall give it in the words of Dr En¬
field, from whofe elegant hiftory of philofophy we have
extracted by much the moft valuable parts of this ar¬
ticle.
“ The profeffed objefl of Plato’s firft vifit to Sicily,
which happened in the 40th year of his age, during the
reign of the elder Dionyfius the fon of Hermocrates,
was, to take a furvey of the ifland, and particularly to
obferve the wonders of Mount iEtna. Whilft he was
refident at Syracufe, he was employed in the inftruSion
of Dion, the king’s brother-in-law, who poffeffed ex¬
cellent abilities, though hitherto reftrained by the ter¬
rors of a tyrannical government, and relaxed by the lux¬
uries of a licentious court. Difgufted by the debauch¬
ed manners of the Syracufans, he endeavoured to refeue
his pupil from the general depravity. Nor did Dion
difappoint his preceptor’s expe&ations. No fooner had
he received a tafte of that philofophy which leads to
virtue, than he was fired with an ardent love of wifdom.
Entertaining an hope that philofophy might produce
the fame effeft upon Dionyfius, he took great pains to
procure an interview between Plato and the tyrant. In
the courfe of the conference, whilft Plato was difeourfing
on the fecurity and happinefs of virtue, and the miferies
attending injuftice and oppreflion, Dionyfius, perceiving
that the philofopher’s difeourfe was levelled againft the
vices and cruelties of his reign, difmiffed him with high
difpleafure from his prefence, and conceived a defign
againft his life. It was not without great difficulty that
Plato, by the affiftance of Dion, made his efcape. A
veffel which had brought over Pollis, a delegate from
Sparta, was fortunately at that time returning to Greece.
Dion engaged Pollis to take the charge of the philofo-
pher, and land him fafely in his native country 5 but
Dionyfius difeovered the defign, and obtained a promife
from Pollis, that he would either put him to death or
fell him as a Have upon the paffage. Pollis according¬
ly fold him in the ifland of ^Egina ; the inhabitants of
which were then at war with the Athenians. Plato
could not long remain unnoticed : Anicerris, a Cyrenaic
philofopher, who happened to be at that time in the
ifland, difeovered the ftranger, and thought himfelf hap¬
py in an opportunity of ffiowing his refpedl for fo illuf¬
trious a philofopher : he purchafed his freedom for 30
minae, or 84I. ics. fterling money, and fent him home
to Athens. Repayment being afterwards offered to
Anicerris by Plato’s relations, he refufed the money,
faying, with that generous fpirit ■which true philofophy
always infpires, that he faw no reafon why the relations
of Plato fhould engrofs to themfelves the honour of fer-
ving him.”
After a ftiort interval, Dionyfius repented of his ill-
placed l
P L A [ 632 ] P L A
placed refentment, and wrote to Plato, earnellly requell¬
ing him to repair his credit by returning to Syracufe j
to which Plato gave this high-fpirited ant'wer, that phi-
lofophy would not allow him leifure to think of Diony¬
sus. He was, however, prevailed, upon by his friend
Dion to accept of the tyrant’s invitation to return to
Syracufe, and take upon him the education of Dionyfius
the younger, who was heir apparent to the monarchy.
He was received by Dionyfius the reigning fovereign
with every poffible appearance of refpeft j but after fee¬
ing his friend banilhed, and being himfelf kept as a pri-
foher at large in the palace, he was by the tyrant fent
back into his own country, with a promife that both he
and Dion fhould be recalled at the end of the war in
which the Sicilians were then engaged. This promife
was not fulfilled. The tyrant wiflied for the return of
Plato $ but could not refblve to recal Dion. At laft,
however, having probably promifed that the philofopher
Ihould meet his friend at the court of Syracufe, he pre¬
vailed upon Plato to vifit that capital a third time.
When he arrived, the king met him in a magnificent
chariot, and conduced him to his palace. The Sicilians
too rejoiced in his return *, for they hoped that the wif-
dom of Plato would at length triumph over the tyranni¬
cal fpirit of the prince. Dionyfius feemed wholly di-
vefted of his former refentments, liftened with apparent
pleafure to the philofopher’s doftrine, and, among other
expreflions of regard, prefented him with eighty talents
of gold. In the midft of a numerous train of philofo-
phers, Plato now poffeffed the chief influence and autho¬
rity in the court of Syracufe. Whilfl: Ariftippus. was
enjoying himfelf in fplendid luxury ; whilfl: Diogenes
was freely indulging his acrimonious humour; and whilft
yEfchines was gratifying his third: after riches;—Plato
fupported the credit of philofophy with an air of digni¬
ty, which his friends regarded as an indication of fupe-
rior wifdom, but which his enemies imputed to pride.
After all, it was not in the powrer of Plato to prevail
upon Dionyfius to adopt his fyftem of policy, ©r to re¬
cal Dion from his exile. Mutual diftruft, after a fhort
interval, arofe between the tyrant and the philofopher;
each fufpe&ed the other of evil defigns, and each en¬
deavoured to conceal his fufpicion under the difguife of
refpedl. Dionyfius attempted to impofe upon Plato by
condefcending attentions, and Plato to deceive Dionyfius
by an appearance of confidence. At length, the phi¬
lofopher became fo much diflatisfied writh his fitua-
tion, that he earneftly requefted permiflion to return to
Greece, which was at laft granted him, and he was fent
home loaded wdth rich prefents. On his way to A-
thens, pafling through Elis during the celebration of
the Olympic games, he w7as prefent at this general
affembly of the Greeks, and engaged univerfal atten¬
tion.
From this narrative it appears, that if Plato vifited
the courts of princes, it w’as chiefly from the hope of
feeing his ideal plan of a republic realized ; and that his
talents and attainments rather qualified him to fhine in
the academy than in the council or the fenate.
Plato, now reftored to his country and his fchool, de¬
voted himfelf to fcience, and fpent the laft years of a
long life in the inftru&ion of youth. Having enjoyed
the advantage of an athletic conftitution, and.lived all
his days temperately, he arrived at the 81ft, or accord¬
ing to fome writers the 79th, year of his age, and died,
through the mere decay of nature, in the firft year of
the hundred and eighth Olympiad. He palfed his whole
life in a ftate of celibacy, and therefore left no naturr.l
heirs, but transferred his effe£ts by will to his friend
Adiamantus. The grove and garden, which had been
the feene of his philofophical labours, at laft afforded
him a fepulchre. Statues and altars wTere eredled to his
memory ; the day of his birth long continued to be ce¬
lebrated as a feftival by his followers ; and his portrait
is to this day preferved in gems : but the moft Lifting
monuments of his genius are his writings,' which have
been tranfmitted, without material injury, to the prefeiit
times. .
The character of this philofcpher has always been
high. Befides the advantages of a noble birth, he had
a large and comprehenfive underftanding, a vaft fund of
wit and good tafte, great evennefs and fweetnefs of tem¬
per, all cultivated and refined by education and travel;
fo that it is no wonder if he was honoured by his coun¬
trymen, eftcemed by ftrangers, and adored by his fcho-
lars. The ancients thought more highly of Plato than
of all their philofopherS: they always called him the Di¬
vine Plato; and they feemed refolved that las defeent
fhould be more than human. “ There are (fays Apu-
leius) who affert Plato to have fprung from a more fub-
lime conception ; and.that his mother Peridlione, who
was a very beautiful woman, w7as impregnated by Apol¬
lo in the ftiape of a fpedlre.” Plutarch, Suidas, and
others, affirm this to have been the common report at
Athens. When he was an infant, his father Ariflo
went to Hymettus, with his wife and child, to facrifice
to the mufes; and while they were bufied in the divine
rites, a fwarm of bees came and diftillechtheir honey up¬
on his lips. This, fays Tully, was confidered as a pre-
fage of his future eloquence. Apuleius relates, that So¬
crates, the night before Plato was recommended to him,
dreamed that a young fwan fled from Cupid’s altar in
the academy, and fettled in his lap ; thence foared to
heaven, and delighted the gods with its mufic : and when
Arifto the next day prefented Plato to him, “ Friends
(fays Socrates), this is the fwan of Cupid’s academy.”
The Greeks loved fables: they ftiow however in the pre¬
fent cafe, what exceeding refpeft w as paid to the me¬
mory of Plato. Tully perfeftly adored him ; tells us,
how he was juftly called by Pansetins the divine, the
mojl wife, the mojl /acred, the Homer of philofoffers ;
entitled him to Atticus, Dei/s ille nofer-, thinks, that if
Jupiter had fpoken Greek, he would have fpoken in
Plato’s language, and made him fo implicitly his guide in
wifdom and philofophy, as to declare, that he had rather
err with Plato than be right with any ond elfe. But,
panegyric afide, Plato wTas certainly a very wxmderful
man, of a large and comprehenfive mind, an imagination
infinitely fertile, and of a moft flowing and copious elo¬
quence. Neverthelefs, the ftrength and heat of fancy
prevailing in his compofition over judgement, he wras too
apt to foar beyond the limits of earthly things, to range
in the imaginary regions of general and abftrafted ideas;
and on which account, though there is always a great-
nefs and fublimity in his manner, he did not philofo-
phize fo much according to truth and nature as Ari-
ftotle, though Cicero did not fcruple to give him the
preference.
The waitings of Plato are all in the way of dialogue ;
where he feems to deliver nothing from himfelf, but every
Plato
, !!.
Platonifm.
P LA [ 633
thing as tlie fentiments and opinions of others, of So¬
crates chiefly, of Timaeus, &c. He does not mention
himfelf anywhere, except once in his Phaedo, and ano¬
ther time in his Apology for Socrates. His ftyle, as
Ariftotle obferved, is betwixt profe and verfe : on which
account, fome have not fcrupled to rank him with the
poets. There is a better reafon for fo doing than the
elevation and grandeur of his ftyle : his matter is often¬
times the offspring of imagination, inftead of dodfrines
or truths deduced from nature. The firft edition of
Plato’s works in Greek was put out by Aldus at Ve¬
nice in 1513 ; but a Latin verfion of him by Marfilius
Ficinus had been printed there in 1491. They were
reprinted together at Lyons in 1588, and at Francfort
in 1602. The famous printer Henry Stephens, in 1578,
gave a moft beautiful and corredt edition of Plato’s
works at Paris, with a new Latin verfion by Serranus,
in three volumes folio ; and this defervedly paffes for the
beft edition of Plato : yet Serranus’s edition is very ex¬
ceptionable, and in many refpedts, if not in all, inferior
to that of Ficinus.
PLATONIC, fomething that relates to Plato, his
fchool-philofophy, opinions, or the like. Thus, plato¬
nic love denotes a pure fpiritual affedtion, for which
Plato was a great advocate, fubfifting between the dif¬
ferent fexes, abftradted from all carnal appetites, and re¬
garding no other objedt but the mind and its beauties ;
or it is even a fincere difinterefted friendftrip fubfifting
between perfons of the fame fex, abftradled from any
felfilh views, and regarding no other objedt than the
perfon, if any fuch love or friendthip has aught of a
foundation in nature.
PLATONIC Year, or the Great Year, is a period of
time determined by the revolution of the equinoxes, or
the fpace wherein the ftars and conftellations return to
their former places in refpedt of the equinoxes. The
platonic year, according to Tycho Brahe, is 25816, ac¬
cording to Ricciolus 25910, and according to Caflini
24800 years.
This period once accompliftied, it was an opinion
among the ancients that the world was to begin anew,
and the fame feries of things to turn over again.
PLATONISM, the philofophy of Plato, which
was divided into three branches, theology, phyjtcs, and
mathematics. Under theology were comprehended meta-
phyfics and ethics, or that which in modern language is
called moral philofophy. Plato wrote likewife on dia-
teBics, but with • fuch inferiority to his pupil Ariftotle,
that his works in that department of fcience are feldom
mentioned.
The ancient philofophers always began their theologi¬
cal lyftems with fome difquifition on the nature of the
gods, and the formation of the world ; and it was a
iundamental doftrine with them, that from nothing no¬
thing can proceed. We are not to fuppofe that this ge¬
neral axiom implied nothing more than that for every
effect there muft be a caufe ; for this is a propofition
which no man will controvert who underftands the terms
in which it is expreffed : but the ancients believed that a
proper creation is impoflible even to omnipotence, and
that to the produftion of any thing a material is not lefs
neceffary than an efficient caufe, (fee Metaphysics, N°
264—304.). That with refpecf to this important que-
ftion, Plato agreed with his predeceffors and contempo¬
raries, appears evident to ut from the whole tenor of his
Vol. XVL Part I.
]
P L A
Timceus. We agree with Dr Enfield * in thinking, that Platonifm.
in this dialogue, which comprehends his whole doftrine '
on the fubjedt of the formation of the univerfe, matter ,
is fo manifeftly fpoken of as eternally co-exifting with 1 -
God, that this part of his dodtrine could not have been
miftaken by fo many learned and able writers, had they
not been feduced by the defire of eftabliftiing a coinci¬
dence of dodtrine between the writings of Plato and
Mofes. It is certain that neither Cicero f, nor Apu- (- Ac.
leius J, nor Alcinous §, nor even the later commentator c- 6*
Chalcidius, underftood their mafter in any o^her fenfe ! 1'
than as admitting two primary and incorruptible princi- 1 ~
pies, God and matter; to which we thall afterwards fee
reafon to add a third, namely ideas. The paffages
quoted by thofe who maintain the contrary opinion are
by no means fufhcient for their purpofe. Plato, it is
true, in his Timaeus, calls God the parent of the univerfe,
and in his Sophifta fpeaks of him as “ forming animate
and inanimate beings, which did not before exift but
thefe exprefltons do not neceflarily imply that this off-
fpring of Deity was produced from nothing, or that no
prior matter exifted from which thefe new beings were
formed. Through the whole dialogue of the Timaeus,
Plato fuppofes two eternal and independent caufes of all
things ; one, that by which all things are made, which
is God; the other, that from which all things are made,
which is matter. He diftinguffhes between God, mat¬
ter, and the univerfe, and fuppofes the architedl of the
world to have formed it out of a mafs of pre-exiftent
matter. Matter, according to Plato, is an eternal and
infinite principle. His doftrine on this head is thus ex¬
plained by Cicero ||. “ Matter, from which all things f! Ac. Qu.
are produced and formed, is a fubftance without form or c* 8*
quality, but capable of receiving all forms, and under¬
going every kind of change; in which, however, it
never fuffers annihilation, but merely a folution of its
parts, which are in their nature infinitely divifible, and
move in portions of fpace which are alfo infinitely divi¬
fible. When that principle wdiich we call quality is
moved, and a£ls upon matter, it undergoes an entire
change, and thofe forms are produced, from which arifes
the diverfined and coherent fyftem of the univerfe.”
This doftrine Plato unfolds at large in his Timaeus, and
particularly infifts upon the notion, that matter has ori¬
ginally no form, but is capable of receiving any. He
calls it the mother and receptacle of forms, by the union
of which writh matter the univerfe becomes perceptible
to the fenfes •, and maintains, that the vifible wrorld
owes its forms to the energy of the divine intelleftual
nature.
Our author is fupported in drawing this inference by
the teftimony of Diogenes Laertius, who furely un¬
derftood the language and dogmas of Plato better than
the moft accompliftied modern fcholar can pretend to
do ; yet a learned writer * has lately expreffed great * Dr Ogil-
furprife that any one ftrould confider matter as having^*
been, in Plato’s opinion, uncreated ; and he boldly af¬
firms, that Laertius, inftead of afferting that fpirit and
matter were the principles of all things, ought to have
faid that God alone, in Plato’s eftimation, was their ori¬
ginal.—-To prove this, he gives from the Timseus a quo¬
tation, in which the founder of the academy declares
that God framed heaven and earth, and the inferior dei¬
ties ; and that as he fafhioned, fo he pervades all na¬
ture. He obferves, that Cicero denominates the god of
4 k Plato
P L A [ 634 ] P L A
Platonifni. Plato the maker, and the god of Ariflotle only the go-
U ^ ' vernor, of the world. And, to fatisfy thofe who may
demand a particular proof of Plato’s having taught a
real creation, he affirms that his writings abound with
declarations on the fubject, of which the meaning cannot
Theology 6/'oe mifapprehended. “ With this purpofe (fays he) Pla-
ITato. j-q denominates at one time the principles or fubftance of
all things, Tivo^.xru 3-zov Avtftuvvyov, the produdtions of
the efficient Deity, and at others enters more particular¬
ly into the queftion. Thus, he obferves, that many per-
fons are ignorant of the nature and power of mind or in¬
tellect;, ‘ as having exiited at the beginning, antecedent
to all bodies.’ Of this mind, he obferves, that it is
without exception Tr^crovTxn, of all things the
mojl ancient; and he fubjoins, in order to remove all
doubt of his purpofe, that it is alfo the
caufe or principle of motion.'1'1
With all poffible refpe£t for Dr Ogilvie, of whofe
piety and erudition we are thoroughly convinced, we
mult take the liberty to fay, that to us the declarations
of Plato on this fubjeft appear much lefs precife and
explicit than they appear to him \ and that the inference
which he would draw from the words of Cicero feems
not to flow neceffarily from the fenfe of thofe words.
That Plato believed God to have framed the heaven and
the earth, and to have fajhioned all nature, is a pofition
which, as far as we know, has never been controverted 5
but between framing or fajhioning the chaos or i/M
and calling the univerfe into exiftence from non¬
entity, there is an infinite and an obvious difference.
The diftincfion made by Cicero between the God of
Plato and the God of Ariftotle is a juft diftimftion, but
it will not bear the fuperftruClure which the learned
doctor builds upon it. Ariftotle maintained tiie eter¬
nity of the world in its prefent form. Plato certainly
taught that the firft matter was in time reduced from a
chaotic ftate into form by the power of the Demiurgus 5
but we have feen nothing in his writings which explicitly
declaies his belief that the frfl matter was itfelf created.
The learned Cudworth, who wifhed, like Dr Ogilvie,
to find a coincidence of doftrine between the theology
of Plato and that of the Gofpel, ftrained all his facul¬
ties to prove that his favourite philofopher taught a
proper creation : but he laboured in vain. He gives a
number of quotations in fupport of his pofition ; of
which we fhall here infert only thofe two upon which
Dr Ogilvie feems to lay the greateft ftrefs. Plato, fays
the author of the Intelleftual Syftem, calls the one
God (a) 05 ovgstvov y-au 6t»vs, jeon txvtcc. ra zv ovgxv&i
ucti tx £y ccocv, xxi vtto yr,; xtxvtx cgyx~irxi— He that
makes earth, and heaven, and the gods, and doth all
things both in heaven, and hell, arid under the earth.
And, again, “ he by whofe efficiency the things of the
world (icrrsgey eysvsro, tt^ots^ov tv:t ovtcc') were afterwards
made when they were not before Both Cudworth Platorfifm.
and Ogilvie think this laft fen fence an explicit declara- 1 1 v—" 1
tion of Plato’s belief in the creative power of God : but *
that they are miftaken has been evinced byMoflieimP-
with a force of argument which will admit of no reply.
In that part of the Sophifl from which the quotation is
taken, Plato confiders the livvctfs.iv ToiYirix-riv, of which he
is treating, as belonging both to God and to man , and
he defines it in general to be “ a certain power which is.
the caufe that things may afterwards be which were not
before.” Cudwmrth withes to confine this definition to
the divine power 5 and adds from himlelf to the text
which he quotes the following words, which are not
in Plato, or FROM an antecedent non-existence
BROUGHT FORTH INTO being ! That the incomparable
author intended to deceive his reader, w7e are far from
imagining : his zeal for Platonifm had deceived liimfelf.
Plato’s definition comprehends the avvapiv tcoivtixsis f as f Mofch.
well of man as of God ; and therefore cannot infer a "j't -
creative powTer anywhere, unlefs the father of the acade- cajj' ^ f 1
my w7as fo very abfurd as to fuppofe human artifts the n. xi.
creators of thofe machines which they have invented
and made ! Moflieim thinks that Cudworth was mifled
by too implicit a confidence in F/cinus ; and it is not
impoflible that Dr Ogilvie may have been fvvayed by
the authority, great indeed, of the author of the Intel-
lecfual Syftem.
That intellecl exifted antecedent to all bodies is in¬
deed a Platonic dogma, from which Dr Ogilvie, after
Cudworth, wifhes to infer that the doffrine of the crea¬
tion wras taught in the academy ; but Dr Ogilvie knows,
and no man knew better than Cudworth, that Plato,
with every other Greek philofopher, diftinguifhed be¬
tween body and matter; and that though he held the
priority ©f intelledft to the former, it by no means fol¬
lows that he believed it to have exifted antecedent to
the latter. That he believed mind, or rather foul (for
he diftinguiflies between the two), to be the caufe or
principle of motion, cannot be denied ; but we are not
therefore authorifed to conclude, that he likewife be¬
lieved it to be the caufe of the exiftence of matter. That
he believed mind to be the mo ft ancient of all things,
taking the word things in the molt abfolute fenfe, can¬
not be true, fince by Dr Ogilvie’s own acknowledgement
he held the exiftence and eternity of ideas, not to add
that he believed to Iv or T’«y«0ov—the firft hypoftafis in
his trinity, to be fuperior to mind and prior to it, though
not in time, yet in the order of nature. When there¬
fore he calls mind the moft ancient of all things, he muft
be fuppofed to mean only, that it is more ancient than all
bodies and inferior fouls. It is no reflexion on the
charafter of Plato that he could not, by the efforts of his
own reafon, acquire any notion of a proper creation j
fince we, who have the advantage of his writings, and of
writings
(a) Moftieim affirms that this quotation is nowhere to be found in the writings of Plato. He therefore at firft:
fufpefted that the learned author, in looking haftily over Plato’s 10th book He Legibus, had transferred to God
what is there faid of the anima miindi, leading by its own motions every thing in the heaven, the earth, and the
fea, and that he had added fomething of his own. He dropped that opinion, however, when he found Plato, in the
10th book of his Republic, declaring it to be as “ eafy for God to produce the fun, moon, ftars, and earth, &c. from
himfelf, as it is for us to produce the image of ourfelves, and whatever elfe we pleafe, only by interpofing a looking-
glafs.” In all this power, however, there is nothing fimilar to that of creation.
P L A [6
Platomfm. writings infinitely more valuable, to inftruft us, find it
* v ' extremely difficult, if not impoffible, to conceive bow
any thing can begin to be. We believe the fa£t on the
authority of revelation ; but ffiould certainly have never
agitated fuch a queftion, had it not been dated to us by
writers infpired with celeltial wifdom.
In the Platonic cofmogony we cannot therefore doubt
» but that the eternity of the vAjj r^ulri ^vas taken for grant¬
ed. Whether it was an eternal and neceflary emana¬
tion from an eternal mind, is not perhaps quite fo evi¬
dent, though our own opinion is, that it was believed
to be felf-exident. But be this as it may, which is not
worth difputing, one thing is certain, that Plato did
not believe it to have a fingle form or quality which it
did not receive either from the Demiurgus or the Pfi/che
—the fecond or third perfon of this trinity. Except
Ariilotle, all the Greek philofophers, who rvere not
materialifts, held nearly the fame opinions refpefting the
origin of the world •, fo that in examining their fytlems
we ihall be greatly mified if we underftand the terms
incorporeal and immaterial as at all fynonymous. It
was alfo a do£!rine of Plato, that there is in matter a ne-
ceflary but blind and refraftory force j and that hence
arifes a gropenfity in matter to diforder and deformity,
which is the caufe of all the imperfeflion which appears
in the works of God, and the origin of evil. On this
fubjeft Plato writes with wonderful obfcurity : but, as
tar as we are able to trace his conceptions, he appears to
have thought, that matter, from its nature, refifts the
will of the Supreme Artificer, fo that he cannot per-
fe£lly execute his defigns ; and that this is the caufe of
the mixture of good and evil which is found in the ma¬
terial world.
Plato, however, was no materialift. He taught, that
there is an intelligent caufe, which is the origin of all
fpiritual being, and the former of the material world.
The nature of this great being he pronounced it difficult
to difcover, and when difcovered, impoffible to divulge.
The exitlence of God he inferred from the marks of in¬
telligence, which appear in the form and arrangement of
bodies in the vifible world : and from the unity of the
material fyftem he concluded, that the mind by which
it was formed muft be one. God, according to Plato,
is the fupreme intelligence, incorporeal, without be¬
ginning, end, or change, and capable of being perceived
only by the mind. He certainly diflinguithed the Dei¬
ty not only from body, and whatever has corporeal
qualities, but from matter itfelf, from which all things
are made. He alfo afcribed to him all thofe qualities
which modern philofophers afcribe to immaterial fub-
Ifance : and conceived him to be in his nature fimple,
uncircumfcribed in fpace, the author of all regulated
motion, and, in fine, pofieffed of intelligence in the high-
eft perfeftion.
His notions of God are indeed exceedingly refined,
and fuch as it is difficult to fuppofe that he could ever
have acquired but from fome obfcure remains of prime¬
val tradition, gleaned perhaps from the priefts of Egypt
or from the philofophers of the Eaft. In the Divine
Nature he certainly believed that there are two, and
P L A
probably that there are three, hypoflafes, whom he called Platonifm.
to oy and to |y, yoyj and 4'V^jj. The firft he confidered
as felf-exiftent, and elevated far above all mind and all
knowledge j calling him, by way of eminence, the being,
or the one. The only attribute which he acknowledged
in this perfon was goodnefs *, and therefore he frequent¬
ly ftyles him to —the good, or ejfential goodnefs.
The fecond he confidered as mind, the wifdontor reafon
of the firft, and the maker of the world; and therefore
he ftyles him yonj Aoyo? and ^uiov^/of. The third
he always fpeaks of as the foul of the world; and hence
calls him 4'vX/‘/i’ or >coa-poy. He taught that
the fecond is a neceffary emanation from the firf, and
the third from the fecond, or perhaps from the frjl and
fecond.
Some have indeed pretended, that the Trinity, which
is commonly called Platonic, wras a fi&ion of the later
Platonifts, unknown to the founder of the fchool: but
any perfon who ffiall take the trouble to ftudy the wni-
tings of Plato, will find abundant evidence that he really
afferted a triad of divine hypoftafes, all concerned in the
formation and government of the world. Thus in his
10th book of Laws, where he undertakes to prove the
exiftence of a Deity in onpofition to atheifts, he afcends
no higher in the demonftration than to the or mun¬
dane foul, which he held to be the immediate and pro¬
per caufe of all the motion that is in the world. But in
other parts of his writings he frequently afl’erts, as fu-
perior to the felf-moving principle, an immoveable m’?
or intellect, which was properly the demiurgus or fra¬
mer of the world ; and above this hypofafs one moft
fimple and abfolutely perfect being, who is confidered in
his I hcology as ctvlcSios the original deity, in contradi-
ftintfhon from the others, who are only i*. feev. Thefe
doftrines are to be gathered from his works at large,
particularly from the Timceus, Philebus, Sophi/la and K-
pinomis: but there is a paffage in his fecond epiftle to
Dionyfius, apparently written in anfwer to a letter, in
which that monarch had required him to give a more
explicit account than he had formerly done of the na¬
ture of God, in which the doftrine of a Trinity feems
to be direftly afferted. “ After having faid that he
meant to wrap up his meaning in‘ fuch obfcurity, as
that an adept only ffiould fully comprehend it, he adds
expreffions to the following import: ‘ Tbe Lord of
Nature is furrounded on all fides by his works : what¬
ever is exifts by his permiffion : he is the fountain and
fource of excellence : around the fecond perfon are placed
things of the fecond order 5 and around the third thofe
of the third degree (b).” Of this obfcure paffage a very
fatisfaftory explanation is given in Dr Ogilvie’s 7'heo-
logy of Plato, to which the narrow limits prefcribed to
fuch articles as this compel us to refer the reader. We
ffiall only fay, that the account which we have given of
the Platonic trinity is ably fupported by the doftor.
In treating of the eternal emanation of the fecond
and third hypoftafes from the firft, the philofophers of
the academy compare them to light and heat proceed¬
ing from the fun. Plato himfelf, as quoted by Dr Cud-
worth, illuftrates his doflrine by the fame comparifon.
4 L 2
For
<ru
(b). “ TTige ruv Truvrm ficccriXicc,, Truvftri, xeti Ekuvov inna. TrxvTet.
^tyn^ct, ncti Tgmv t* TgiTK. Open p. 1269.
Ex,iiv65 atrix irxyrm ruv Kxhm.
P L A r 636 1 P L A
Platonifm. For “ rmyxSov or the firft hypoftahs, is in the intellec-
■“ tual world the fame (he fays) to intelleft and intelli-
gibles that the fun is in the corporeal world to vifion
and vifibles j for as the fun is not vilion itfelf but the
caufe of vilion, and as that light hyywhich we fee is not
the fun but only a thing like the fun ; fo neither is the
Supreme or Higheft Good properly knowledge, but the
caufe of knowledge ^ nor is intelledl, conlidered as fuch,
the bell and moll perfeft being, but only a being ha¬
ving the form of perfection.” Again, “ as the firn caufes
other things not only to become vilible but alfo to be
generated ; fo the Supreme Good gives to things not only
their capability of being known, but alfo their very ef-
fences by which they fublilf j for this fountain of the
Deity, this higheft good, is not itfelf properly elfence,
but above elfence, tranfcending it in refpeCl both of dig¬
nity and of power.”
The refemblance which this trinity of Plato bears to
that revealed in the gofpel mull be obferved by every
attentive reader j but the two doClrines are likewife in
fome refpeds exceedingly dillimilar. The third hypo-
flalis in the Platonic fyllem appears in no point of view
co-ordinate with the firlt or fecond. Indeed the firll is
elevated far above the fecond, and the third funk Hill
farther beneath it, being conlidered as a mere foul im-
merfed in matter, and forming with the corporeal world,
to which it is united, one compound animal. Nay, it
does not appear perfectly clear, that Plato confidered
his tov x.oe-pov as a pure fpirit, or as having fublilt-
ed from eternity as a diftinCt Hypq/Iajis. “ This go¬
verning fpirit, of whom-the earth, properly fo called, is
the body, conlilted, according to our author’s philofo-
phy, of the fame and the other ; that is, of the firll
matter, and of pure intelligence, framed to a6tuate the
machinery of nature. The Supreme Being placed him
in the middle of the earth ; which, in the vivid idea of
Plato, feemed itfelf to live, in confequence of an influ¬
ence that was felt in every part of it. From this feat
his power is reprefented as being extended on all fides to
the utmoll limit of the heavens ; conferring life, and
preferving harmony in the various and complicated parts
of the univerfe. Upon this being God is faid to have
looked with peculiar complacency after having formed
him as an image of himfelf, and to have given beauty
and perfeCt proportion to the manfion which he was de-
Itined to occupy. According to the doCtrine of Timse-
us, the Supreme Being llruck out from this original
mind innumerable fpirits of inferior order, endowed with
principles of reafon ; and he committed to divinities of
fecondary rank the talk of invefting thefe in material
forms, and of difperfing them as inhabitants of the fun,
moon, and other celeltial bodies. He taught alfo, that
at death the human foul is reunited to the tov koc-
ftov, as to the fource from wflrich it originally came.”
Such is the third perfon of the Platonic triad, as we
find his nature and attributes very accurately Hated by
Dr Ogilvie 5 and the Chrillian philofopher, who has no
particular fyllem to fupport, will not require another
proof that the triad of Plato differs exceedingly from the
Trinity of the Scriptures. Indeed the third hypollafis
in this triad has fo much the appearance of all that the
ancients could mean by that which we call a creature,
that the learned Cudworth, who wilhed, it is difficult
to conceive for what reafon, to find the fublimelt my-
kery of the Chriilian faith explicitly taught in the writ¬
ings of a pagan philofopher, was forced to fuppofe that PJatottifm.
Plato held a double ^v^v), or foul, one iyKoa-fuov, incor-
porated wflth the material world, and the other vn^xor-
y,.ov or fupramundane, which is not the foul but the go¬
vernor of the univerfe. We call this a mere hypothe-
fis i for though the author difplays vail erudition, and
adduces many quotations in which this double pfyche is
plainly mentioned, yet all thofe quotations are taken
from Platonills who lived after the propagation of the
gofpel, and who, calling themfelves ecleBics, freely
Hole from every fe£l fuch dogmas as they could incorpo¬
rate with their own fyllem, and then attributed thofe
dogmas to their mailer. In the -writings of Plato him¬
felf, there is not fo much as an allufion to this fupra¬
mundane pfyche * j and it is for this reafon (the * Mofcb.
of wdiich he treats being fo very inferior to the ^yifuov^yoi ed. Cud.
and uyu.Qov') that we have expreffed with hefitation his sXft- Intel,.
belief of three hypollafes in the divine nature. Yet that0- $ ^<S*
he did admit fo many, feems more than probable both"
from the paffage illullrated by Dr Ogilvie, and from the
attempt of Plotinus, one of his followers, to demonftrate
that the number can be neither greater nor lefs. That
his dodlrine on this fubjedl Ihould be inaccurate and er¬
roneous, can excite no wonder ; whillt it mull be con-
feffed to have fuch a refemblance to the truth, and to be
fo incapable of being proved by reafoning from effedls
to caufes, that we could not doubt of his having inhe¬
rited it by tradition, even though we had not complete
evidence that fomething very fimilar to it was taught
long before him, not only by Pythagoras and Parmeni¬
des, but by the philofophers of the call.
We have faid that the Demiurgus was the maker of
the world from the firll matter which had exilted from
eternity j but in Plato’s cofmogony there is another
principle, more myllerious, if poffible, than any thing
which we have yet mentioned. This is his intelledlual
fyllem of ideas, which it is not eafy to colled! from his
writings, whether he confidered as independent exillences,
or only as archetypal forms, which had fubfilled from
eternity in the /\«yss or divine intelledl. On this fubjedl
he writes with fuch exceeding obfcurity, that men of
the firll eminence, both among the ancients and the mo¬
derns, have differed about his real meaning. Some have
fuppofed, that by ideas he meant real beings fubfilling
from eternity, independent of all minds, and feparate
from all matter; and that of thefe ideas he conceived
fome to be living and others to be without life. In this
manner his dodtrine is interpreted by Tertullian * among * ^
the ancients, and by the celebrated Brucker -f- among Anima.
the moderns; and not by them only, but by many t Hijlor.
others equally learned, candid, and acute. Cudworth,^
on the other hand, with his annotator Molheim, con- 1
tend, that by his ideal world Plato meant nothing more
than that there exilled from eternity in the Xoyof or mind
of God a notion or conception of every thing which was
in time to be made. This is certainly much more pro¬
bable in itfelf, than that a man of enlarged underftand-
ing Ihould have fuppofed, that there are fomewhere in
extramundane fpace real living incorporeal beings eat¬
ing and drinking, which are the ideas of all the animals
which ever have been or ever will be eating and drink¬
ing in this world. Yet Mofheim candidly acknow¬
ledges, that if the controverfy were to be decided by the
votes of the learned, he is doubtful whether it wmuld be
given for or againf! him) and Cudworthj though he
pleads
P L A r 637 ] P L A
Platomfm. pleads the caufe of his mafter with much ingenuity,
owns> that on this fubjeft his language cannot be vindi¬
cated. This indeed is mod: true ; for Plato contends,
that his ideas are not only the obje61s of fcience, but
alfo the proper or phyfical caufes of all things here be¬
low j that the idea of fimilitude is the caufe of the re-
femblance between two globes j and the idea of didimi-
litude the caufe that a globe does not refemble a pyia-
mid : he likewife calls them overixfyeffences orfibfances,
and many of his followers have pronounced them to be
animals.
Thefe wonderful expreflions incline us to adopt with
fome hefitation the opinion dated by Dr Enfield. This
hiftorian of philofophy having obferved, that fome of
the admirers of Plato contend, that by ideas exifling in
the reafon of God, nothing more is meant than concep¬
tions formed in the Divine mind, controverts this opinion
with much effect. “ By ideas, Plato (fays he) appears
to have meant fomething much more myllerious ; name¬
ly, patterns or archetypes fubiiding by themfelves, as
real beings, mtus ovlx in the Divine reafon, as in their
original and eternal region, and ifluing thence to give
lorm to fenfible things, and to become obje&s of con¬
templation and fcience to rational beings. It is the
dodtrine of the Timaeus, that 0 Myirpts ra Gm, the rea¬
fon of God, comprehends exemplars of all things, and
that this reafon is one of the primary caufes of things.
Plutarch fays, that Plato fuppofes three principles, God,
Matter, and Idea. Judin Martyr, Pfeudo-Origen, and
others, aflfert the fame thing.
“ That this is the true Platonic dodlrine of ideas wall
appear probable, if we attend to the manner in which
Plato framed his fydem of opinions concerning the ori¬
gin of things. ‘ Having been from his youth (fays A-
ridotle) converfant with Cratylus, a difciple of Heracli¬
tus, and indrudled in the dodlrine of that fchool, that
all fenfible things are variable, and cannot be proper ob-
jedls of fcience, he reafonably concluded, that if there
be any fuch thing as fcience, there mud exid, befides
fenfible objedls, certain permanent natures, perceptible
only by the intelledi.’ Such natures, divine in their
origin, and eternal and immutable in their exidence, he
admitted into his fydem, and called them ideas. Vifible
things wrere regarded by Plato as fleeting fhades, and
ideas as the only permanent fubdances. Thefe he con¬
ceived to be the proper obje&s of fcience to a mind rai-
fed by divine contemplation above the perpetually vary¬
ing fcenes of the material world.”
It wras a fundamental doftrine in the fydem of Plato,
that the Deity formed the material world after a perfedf
model, confiding of thofe ideas which had eternally fub-
fided in his own reafon ; and yet, with fome appearance
of contradi&ion, he calls this model “ /ivyiexifient, in-
divifible, and eternally generated.'1'1 Nay, he talks of
it as being intelligent as wrell as eternal, and wholly
different from the tranfcripts, which are fubiefted to our
infpeftion. There is fo much mydery, confufion, and
apparent abfurdity, in the whole of this fydem, as it has
come down to us, that we mud fuppofe the friends of
Plato to have been entruded with a key to his efoteric
dodlrines, which has long been lod, otherwife it would
be difficult to conceive how that philofopher could have
had fo many admirers.
With almod every ancient theid of Greece the found¬
er of the academy believed in an order of beings called
daemons, wffiich were fuperior to the fouls of men, and Pfotonifm.
druck off by the Demiurgus from the foul of the world. ' ^ J
Of thefe the reader will find fome account elfevffiere :
(See Daimon and Polytheism). We mention them
at prefent becaufe they make an important appearance
in Plato’s fydem of phyfics, which was built upon them
and upon the doftrine which has been dated concerning
God, matter, and ideas. He taught, that the vifible
world wras formed by the Supreme Architect, uniting
eternal and immutable ideas to the fird matter ; that the
univerfe is one animated being *, including within its li- * Timeetu^
mits all animated natures; that, in the formation of the
vifible and tangible world, fire and earth were fird form¬
ed, and were afterwards united by means of air and wTa-
ter 5 that from perfect parts one perfecl whole was pro¬
duced, of a fpherical figure, as mod beautiful in itfelf,
and bed fuited to contain all other figures f 5 that the t Ibidx
elementary parts of the world are of regular geometrical
forms, the particles of earth being cubical, thofe of fire
pyramidical, thofe of air in the form of an oftohedron,
and thofe of water in that of an icofohedron ; that thefe
are adjuded in number, meafure, and power, in perfect
conformity to the geometrical law's of proportion ; that
the foul which pervades this fphere is the caufe of its re¬
volution round its centre; and, ladly, that the world
will remain for ever, but that by the adlion of its ani¬
mating principle, it accompliffies certain periods, within
wffiich every thing returns to its ancient place and date.
This periodical revolution of nature is called the Plato¬
nic or great year. See the preceding article.
The metaphyfical d»61rines of Plato, which treat of
the human foul, and the principles of his fydem of
ethics, have been detailed in other articles (See Meta¬
physics, Part III. chap. iv. j and Moral Philofophy,
N° 6.) : but it is wmrthy of obfervation in this place,
that, preparatory to the dudy of all philofophy, he re¬
quired from his difciples a knowledge of the elements of
mathematics. In his Republic, he makes Glaucus, one
of the fpeakers, recommend them for their ufefulnefs in
human life. “ Arithmetic for accounts and didribu-
tions 5 geometry for encampments and menfurations j mu-
lic for folemn fedivals in honour of the gods ; and adro-
nomy for agriculture, for navigation, and the like. So¬
crates, on his part, denies not the truth of all this, but
dill infinuates that they w^ere capable of anfwering an
end more fublime. ‘ You are pleafant (fays he) in
your feeming to fear the multitude, led you diould be
thought to enjoin certain fciences that are ufelefs. ’Tis
indeed no contemptible matter, though a difficult one,
to believe, that through thefe particular fciences the foul
has an organ purified and enlightened, which is dedroyed
and blinded by dudies of other kinds; an organ better
worth faving than a thoufand eyes, in as much as truth
becomes vifible through this alone.'1'1
“ Concerning policy, Plato has written at large in his
Republic and in his Dialogue on Law's. He was fo much
enamoured with his own conceptions on this fubjedt, that
it was chiefly the hope of having an opportunity to rea-
life his plan of a republic which induced him to vifit the
court of Dionyfius. But they who are converfant with
mankind, and capable of calmly invedigating the fprings
of human aftions, will eafily perceive that his projeds
were chimerical, and could only have originated in a
mind replete wffih philofophical enthufiafm. Of this
nothing can be a clearer proof than the defign of admit-
P L A t 638 ] P L A
riatonifm
I!
Flayhoufe.
ting in his republic a community of women, in order to
give reafon an entire controul over defire. The main
objeft of his political inftitutions appears to have been,
the fubj ugation of the paflions and appetites, by means
of the abftraft contemplation of ideas. A fyftem of po¬
licy, raifed upon fuch fanciful grounds, cannot merit a
more diftinft confideration.”
Such is genuine Platonifm as it was taught in the old
academy by the founder of the fchool and his immediate
followers; but when Arcefilaus was placed at the head
of the academics, great innovations were introduced both
into their doftrines and into their mode of teaching
(fee Arcesilaus). This man was therefore confidered
as the founder of what wTas afterwards called the middle
academy. Being a profeffed fceptic, he carried his
maxim of uncertainty to fuch a height, as to alarm the
general body of philofophers, oft'end the governors of the
ftate, and bring juft odium upon the very name of the
academy. At length Carneades, one of the difciples of
this fchool, relinqiiiftiing fome of the more obnoxious te¬
nets of Arcefilaus, founded what has been called the
new academy with very little improvement on the prin¬
ciples of the middle. See Carneades.
Under one or other of thefe forms Platonifm found its
way into the Roman republic. Cicero was a Platonift,
and one of the greateft ornaments of the fchool. A
fchool of Platonifts was likewife founded in Alexandria
in the fecond century of the Chriftian era \ but their
doftrines differed in many particulars from thofe taught
in the three academies. They profeffed to feek truth
wherever they could find it, and to colleft their dogmas
from every fchool. They endeavoured to bend fome of
the principles of Plato into a conformity with the doc¬
trines of the gofpel } and they incorporated with the
w’hole many of the maxims of Ariftotle and Zeno, and
not a few of the fiftions of the eaft. Their fyftem was
therefore extremely heterogeneous, and feldom fo ration ¬
al as that of the philofopher after whofe name they were
called, and of whofe dobtrines we have given fo copious
a detail. See Ammonius, Ecclectics, and Ploti-
PLAUTUS, Marcus Accius, a comic rvriter of
ancient Rome, born in Umbria, a province of Italy.
His proper name was Marcus Accius, and he is fuppofed
to have acquired the furname of Plautus from having
fplay feet. His parentage appears to have been mean ;
fo that fome have thought he was the fon of a {lave.
Aulus Gellius fays that Plautus was diftinguiftied for his
poetry on the theatre, and Cato for his eloquence in the
forum, at the fame time ; and obferves eli'ewhere from
Varro, that he was fo well paid for his plays as to dou¬
ble his ftock in trading, in which he loft all he gained
by the mufes. He is {aid to have been reduced to work
at a mill for his fubfiftence; but Varro adds, that his
wit was his beft fupport, as he compofed three of his
plays during this drudgery. Pie died in the firft
year of the elder Cato’s cenforftrip, about the year of
Rome 369, and 184 before Chrift. We have 20 of his
plays extant, though not all of them entire. Five of
them, comedies, have been elegantly tranflated into Eng-
liftr by Mr B. Thornton, and publifhed in 2 vols 8vo,
1767.
PLAYS. See the following article.
PLAYHOUSE. See Theatre, Amphitheatre,
&c. The moft ancient Engliih playhoufcs were the
Curtain in Shoreditch and the Theatre. In the time of Playhoufe^
Shakefpeare, who commenced a dramatic writer in 1592, "''
there were no lefs than 10 theatres open. Four of thefe
wrere private houfes, viz. that in Blackfriars, the Cock¬
pit or Phcenix in Drury-Lane, a theatre in Whitefriars,
and one in Salifoury court. The other fix were called
public theatres, viz. the Globe, the Srvan, the Rofe,
and the Hope, on the Bank-fide ; the Red Bull, at the
upper end of St John’s ftreet, ahd the Fortune in
in White-crofs ftreet. The two laft were chiefty fre¬
quented by citizens. Mr Malone gives us a pretty co¬
pious account of thefe playhoufes, in a fupplement to
his laft edition of Shakefpeare, which w’e {hall here in-
fert.
“ Moft, if not all (fays he) of Shakefpeare’s plays
were performed either at the Globe or at the Theatre in
Blackfriars. It appears that they both belonged to the
fame company of comedians, viz. his majefty’s fervants,
which title they affumed, after a licence had been
granted to them by King James in 1603, having be¬
fore that time been called the fervants of the lord cham¬
berlain.
“ The theatre in Blackfriars was a private houfe ^
but the peculiar and diftinguiftiing marks of a private
playhoufe it is not eafy to alcertain. It was very final],
and plays were there ulually reprefented by candle light.
The Globe, fituated on the fouthern fide of the river
Thames, was a hexagonal building, partly open to the
weather, partly covered with reeds. It was a public
theatre, and of confiderable fize, and there they always
acled by daylight. On the roof of the Globe, and the
other public theatres, a pole was erefted, to which a
flag was affixed. Thefe flags wTere probably difplayed
only during the hours of exhibition ; and it ffiould Item
from a pafiage in one of the old comedies that they were
taken down during Lent, in which feafon no plays were
prefented. The Globe, though hexagonal at the out-
fide, w7as probably a rotunda w ithin, and perhaps had
its name from its circular form. It might, however,
have been denominated only from its fign, which w7as a
figure of Hercules fupporting the Globe. This theatre
was burnt down in 1613, but it was rebuilt in the fol¬
lowing year, and decorated with more ornament than
had been originally beftowed upon it. The exhibitions
at the Globe feem to have been calculated chiefly for
the lower clafs of people ; thofe at Blackfriars for a
more feledl and judicious audience.
“ A writer informs us, that one of thefe theatres was
a wfinter and the other a fummer houfe. As the Globe
was partly expcfed to the weather, and they afted there
ufually by daylight, it was probably the fummer thea¬
tre. The exhibitions here feem to have been move fre¬
quent than at Blackfriars, at leaft till the year 1604 or
1605,, when the Bank-fide appears to have become lefs
fafhionable and lefs frequented than it formerly had
been. Many of our ancient dramatic pieces wTere per¬
formed in the yards of carriers inns} in which, in the
beginning of Qrieen Elizabeth’s reign, the comedians,
wffio then firft united themfelves in companies, eredled
an occafional ftage. The form of thefe temporary play¬
houfes feems to be preferved in our modern theatre.
The galleries are in both ranged over each other on
three fides of the building. The ftnall rooms under the
lowed of thefe galleries anfwer to our prefent boxes;
and it is obfeivable that thefe, even in theatres which
were
IP L A [ 639 3 t> L A
PI ayViOuf*. were built in a fubfequent period exprefsly for dramatic
L“—v~' --1 exhibitions, ftill retained their old name, and are fre¬
quently called rooms by our ancient writers. The yard
bears a fufficient refemblance to the pit, as at prefent in
ufe. We may fuppofe the ftage to have been raifed in
this area, on the fourth fide, with its back to the gate¬
way of the inn, at which the money for admiffion was
taken. Hence, in the middle of the Globe, and I
fuppofe of the other public theatres, in the time of
Shakefpeare, there was an open yard or area, where the
common people ftood to fee the exhibition ; from which
circumllance they are called by our author groundlings,
and by Ben Johnfon ‘ the underftanding gentlemen of
the ground.’
“ In the ancient playhoufes there appears to have
been a private box, of which it is not eafy to afcertain
the fituation. It feems to have been placed at the fide
of the ftage towards the rear, and to have been at a
lower price : in this fome people fat, either from econo¬
my or fingularity. The galleries, or fcaffolds as they
are fometimes called, and that part of the houfe which
in private theatres was named the pit, feem to have been
at the fame price j and probably in houfes of reputation,
fuch as the Globe, and that in Blackfriars, the price of
admifixon into thofe parts of the theatre was 6d. while
in fome meaner playhoufes it was only id. in others on¬
ly 2d. The price of admiffion into the beft rooms or
boxes was, I believe, in our author’s time, is. ; though
afterwards it appears to ha.ve rifen to 2s. and half-a-
crown.
“ From feveral paffages in our old plays, we learn,
that fpeclators were admitted on the ftage, and that the
critics and wits of the time ufually fat there. Some were
placed on the ground ; others fat on ftools, of which
the price was either 6d. or is. according, I fuppofe, to
the commodioufnefs of the fituation *, and they were at¬
tended by pages, who furniflied them with pipes and
tobacco, which was fmoaked here as well as in other
parts of the houfe : yet it fhould feem that perfons were
fuffered to fit on the ftage only in the private playhoufes,
fuch as Blackfriars, &c. where the audience was more fe-
le61, and of a higher clafs ; and that in the Globe and
other public theatres no fuch licence vras permitted.
“ The ftage was ftrewed with rufhes, which, as we
learn from Hentzner and Caius de Ephemera, was, in
the time of Shakefpeare, the ufual covering of floors in
England. The curtain which hangs in the front of the
prefent ftage, drawn up by lines and pulleys, though not a
modern invention, for it vras ufed by Inigo Jones in the
mafques at court, was yet an apparatus to which the
fimple mechanifm of our ancient theatres had not arrived,
for in them the curtains opened in the middle, and were
drawn backwards and forwards on an iron rod. In fome
playhoufes they were woollen, in others made of filk.—
Towards the rear of the ftage there appears to have been
a balcony, the platform of which w'as probably eight or
ten feet from the ground. I fuppofe it to have been fup-
ported by pillars. From hence, in many of our old plays,
part of the dialogue was fpoken ; and in the front of this
balcony curtains likewife were hung,
“ A doubt has been entertained whether in our ancient
theatres there were fide and other fcenes. The queftion
is involved in fo much obfcurity, that it is very difficult to
form any decided opinion upon it. It is certain, that in
the year i6dj Inigo Jones exhibited an entertainment at Playhoufe-
Oxford, in which moveable fcenes were ufed 3 but he ap-
pears to have introduced feveral pieces of machinery in the
mafques at court, with which undoubtedly the public
theatres were unacquainted. A paffage which has been
produced from one of the old comedies, proves, it muft
be owned, that even thefe were furnifhed with fome pieces
of machinery, which were ufed when it was requifite to
exhibit the defcent of fome god or faint 5 but from all
the contemporary accounts, I am inclined to believe that
the mechanifm of our ancient ftage feldom went beyond
a painted chair or a trap-door, and that few, if any of
them, had any moveable fcenes. When King Flenry VIII.
is to be difcovered by the dukes of Suffolk and Norfolk,
reading in his ftudy, the fcenical direftion in the firft fo¬
lio, 1623, which was printed apparently from play houfe
copies), is, ‘ the king draws the curtain, (/. e. draws it
open), and fits reading penfively for, befides the prin¬
cipal curtains that hung in the front of the ftage, they
ufed others as fubftitutes for fcenes. If a bed-chamber is
to be exhibited, no change of fcene is mentioned 5 but the
property-man is limply ordered to thruft forth a bed.
When the fable requires the Roman capitol to be exhibit¬
ed, we find two officers enter, ‘ to lay culhions, as it were,
in the capitol,’ &c. On the whole, it appears, that our
ancient theatres, in general, were only furniffied -wlih cur¬
tains, and a Angle fcene compofed of tapeftry, which
were fometimes, perhaps, ornamented with piftures ; and
fome paffages in our old dramas incline one to think, that -
when tragedies were performed the ftage was hung with
black.
“ In the early part, at lead, of our author’s * acquaint- * Shale*
ance with the theatre, the want of fcenery feems to have7^arf*
been fupplied by the fimple expedient of writing the
names of the different places where the fcene was laid in
the progrefs of the play, which were .difpofed in fuch a
manner as to be vifible to the audience. The invention
of trap-doors, however, appears not to be modern j for in
an old morality, intitled Allfor Money, we find a margi¬
nal direction which implies that they were very .early in
ufe. The covering, or internal roof of the ftage, was
anciently termed the heavens. It was probably painted
of a Iky-blue colour,-or perhaps pieces of drapery tinged
with blue were fufpended acrofs the ftage to reprefent the
heavens.
“ It is probable that the ftage was formerly lighted by
two large branches, of a form fimilar to thofe now hung
in churches. They gave place in a fubfequent period to
fmall circular wooden frames, furniffied with candles,
eight of which were hung on the ftage, four at either fide,
and thefe within a few years were wholly removed by Mr
Garrick, who, on his return from France, firft introdu¬
ced the prefent commodious method of illuminating the
ftage by lights not vifible to the audience. Many of the
companies of players were formerly fo thin, that one per-
fon played two or three parts ; and a battle on which the
fate of an empire was fuppofed to depend was decided by
half a dozen combatants. It appears to have been a com¬
mon praftice in their mock engagements to difcharge
fmall pieces of ordnance on the ftage. Before the exhi¬
bition began, three flourifties or pieces of mufic were
played, or, in the ancient language, there were three
foundings. Mufic was likewife played between the a£ts.
The inftruments chiefly ufed were trumpets, cornets, and
hautboys, -
P L A
t 640 ]
P L A
PiayHoufe. hautboys. The band, which did not condft of more than
' » five or fix performers, fat in an upper balcony, over what
is now called the ftage-box.
“ The perfon who fpoke the prologue was ufhered in
by trumpets, and ufually wore a long black velvet cloak,
which, 1 fuppofe, was confidered as beft fuited to a fup-
plicatory addrefs. Of this cuftom, whatever might have
been its origin, fome traces remained till very lately, a
black coat having been, if I miftake not, within thefe few
years, the conftant ftage-habiliment of our modern pro-
logue-fpeakers. The drefs of the ancient prologue-
fpeaker is ftill retained in the play that is exhibited in
Hamlet before the king and court of Denmark. The per¬
formers of male characters generally wore periwigs, which
in the age of Shakefpeare were not in common ufe. It
appears, from a paffage in Puttenham’s Art of Knglijh
Poefy, 1589, that vizards were on fome occafions ufed by
the aftors of thofe days •, and it may be inferred, from a
fcene in one of our author’s comedies, that they were
fometimes worn in his time by thofe who performed fe¬
male characters j but this I imagine was very rare. Some
of the female part of the audience like wife appeared in
malks. The ftage-dreffes, it is reafonable to fuppofe,
were much more coftly at fome theatres than at others j
vet the wardrobe of even the king’s fervants at the Globe
and Blackfriars, was, we find, but fcantily furnilhed •,
and our author’s dramas derived very little aid from the
fplendor of exhibition.
“ It is well known, that in the time of Shakefpeare,
and for many years afterwards, female characters were
reprefented by boys or young men. Sir William d’Ave-
nant, in imitation of the foreign theatres, firft introduced
females in the fcene, and Mrs JBetterton is faid to have
been the firft woman that appeared on the Englifii ftage.
Andrew Pennycuike played the part of Matilda in a tra¬
gedy of Davenport’s, in 1655 '■> an<^ ^-r Kynafton aCted
feveral female parts after the Reftoration. Downes, a
contemporary of his, affures us, ‘ that being then very
young he made a complete ftage beauty, performing his
parts fo well, particularly Arthiope and Aglaura, that it
has fince been difputable among the judicious whether
any woman that fucceeded him touched the audience fo
fenfibly as he.?
“ Both the prompter, or book-holder, as he wras fome¬
times called, and the property-man, appear to have been
regular appendages of our ancient theatres. No waiter
that I have met with intimates, that in the time of Shake¬
fpeare it wTas cuftomary to exhibit more than a fingle dra¬
matic piece on one day. The Yorkflrire tragedy, or All's
One, indeed, appears to have been one of four pieces that
■were reprefented on the fame day ; and Fletcher has alfo
a piece called Four Plays in One; but probably thele wTere
either exhibited on fome particular occafion, or were inef¬
fectual efforts to introduce a new fpecies of amufement *,
for rve do not find any other inftances of the fame kind.
Had any ftiorter pieces been exhibited after the principal
performance, fome of them probably would have been
printed: but there are none extant of an earlier date than
the time of the Reftoration. The praCtice, therefore, of
exhibiting two dramas fucceflively in the fame evening,
we may be affured wTas not eftabliihed before that period.
But though the audiences in the time of our author
were not gratified by the reprefentation of more than one
drama in the fame day, the entertainment was diverfified,
and the populace diverted, by vaulting, tumbling, flight
4
of hand, and morris-dancing, a mixture not much more Kayhouf#
heterogeneous than that with wdfich we are daily prefent- J
ed, a tragedy and a farce.
“ The amufements of our anceftors, before the com¬
mencement of the play, w^ere of various kinds, fuch as-
reading, playing at cards, drinking ale, or fmoaking to¬
bacco. It was a common praCtice to carry table-books to
the theatre, and either from curiofity or enmity to the
author, or fome other motive, to wTrite dowm paffages of
the play that wras reprefented : and there is reafon to be¬
lieve that the imperfeCt and mutilated copies of lome
of Shakefpeare’s dramas, which are yet extant, wrere ta¬
ken down in ftiort-hand during the exhibition. At the
end of the piece, the aCtors, in noblemen’s houfes and
in taverns, where plays were frequently performed, pray¬
ed for the health and profperity of their patrons , and in
the public theatres for the king and queen. This prayer
fometimes made part of the epilogue. Hence, probably,
as Mr Steevens has obferved, the addition of Vivant rex
et regina to the modern play-bills.
“ Plays, in the time of our author, began at one o’clock
in the afternoon ; and the exhibition -was ufually finifti-
ed in two hours. Even in 1667 they commenced at
three. When Goffon wrote his School of Abufe, in 1579*
it feems the dramatic entertainments were ufually exhi¬
bited on Sundays. Afterwards they wrere performed on
that and other days indifcriminately. It appears from a
contemporary w'riter, that exhibiting plays on Sunday had
not been abolilhed in the third year of King Charles I.
“ The modes of conveyance to the theatre, anciently
as at prefent, feem to have been various 5 fome going in
coaches, others on horfeback, and many by water.—
To the Globe playhoufe the company probably were
conveyed by water •, to that in Blackfriars the gentry
went either in coaches or on horfeback, and the common
people on foot. In an epigram to Sir John Davis,
the praftice of riding to the theatre is ridiculed as a piece
of affe&ation or vanity, and therefore we may prefume
it was not very general.
“ The long and whimfical titles that are prefixed to
the quarto copies of our author’s plays, I fuppofe to have
been tranfcribed from the play-bills of the time. A con¬
temporary writer has preferved fomething like a play-bill
of thofe days, which feems to corroborate this obferva-
tion *, for if it were diverted of rhime, it wrould bear no
very diftant refemblance to the title pages that ftand be¬
fore fome of our author’s dramas :
-Prithee, what’s the play ?
“ (The firft I vifited this twelvemonth day)
“ They fay “ A new invented play of Purle,
“ That jeoparded his neck to fteal a girl
“ Of twelve j and lying fall impounded for’t,
“ Has hither fent his beard to act his part ;
“ Againft all thofe in open malice bent,
“ That wTould not freely to the theft confent :
“ Feigns all to’s wifli, and in the epilogue
“ Goes out applauded for a famous rogue.”
“ —Now hang me if I did not look at firft
“ For fome fuch fluff, by the fond people’s thruft.”
“ It is uncertain at what time the ufage of giving au¬
thors a benefit on the third day of the exhibition of their
pieces commenced. Mr Oldys, in one of his manufcripls,
intimates that dramatic poets had anciently their benefit
on the firft day that a new play was reprefenfod } a regu¬
lation
P L A
Phyhoufe. lation ivKich would have been very favourable to fomeof
v the ephemeral productions of modern times. But for this
there is not, I believe, any fufficient authority. From
D’Avenant, indeed, we learn, that in the latter part of
the reign of Queen Elizabeth the poet had his bene¬
fit on the fecond day. As it was a general praCtice in
the time of Shakefpeare to fell the copy of the play to the
theatre, I imagine in fuch cafes an author derived no
other advantage from his piece than what arofe from the
fale of it. Sometimes, however, be found it more be¬
neficial to retain the copyright in his own hands ; and
when he did fo, I fuppofe he had a benefit. It is cer¬
tain that the giving authors the profit of the third ex¬
hibition of their play, which feems to have been the
ufual mode during almoft the whole of the laft centnry,
was an eitablilhed cuftom in the year 1612 , for Deck¬
er, in the prologue to one of his comedies printed in
that year, fpeaks of the poet’s third day. The unfor¬
tunate Otwray had no more than one benefit on the
production of a new play ; and this too, it feems, he
was fometimes forced to mortgage before the piece was
aCted. Southerne was the firit dramatic wrriter who
obtained the emoluments arifing from two reprefenta-
tions ; and to Farquhar, in the year 1700, the bene¬
fit of a third was granted. When an author fold his
piece to the (haters or proprietors of a theatre, it re¬
mained for feveral years unpublilhed 5 but wdien that
was not the cafe, he printed it for fale, to which many
feem to have been induced, from an apprehenfion that
an imperfeCl copy might be iffued from the prefs with¬
out their confent. The cuflomary price of the copy of
a play in the time of Shakefpeare appears to have been
twenty nobles^ or fix pounds thirteen (hillings and four
pence. The play when printed was fold for fixpence j
and the ufiial prefent from a patron in return for a de¬
dication was forty (hillings. On the firft day of exhi¬
biting -a new play, the prices of admiflion appear to
have been raifed ; and this feems to have been occa-
fionally pra&ifed on the benefit-nights of authors to
the end of the laft century. The cuftom of paffing
a final cenfure on plays at their firft exhibition is as
ancient as the time of our author 5 for no lefs than
three plays of his rival Ben Jonfon appear to have been
damned j and Fletcher’s Faithful Shepherdefs, and The
Knight of the Burning Peftle, written by him and Beau¬
mont, underwent the fame fate.
“ It is not eafy to afcertain what w^ere the emolu¬
ments of a fuccefsful aftor in the time of Shakefpeare.
They had not then annual benefits as at prefent. The
performers at each theatre feem to have (hared the pro¬
fits afifing either from each day’s exhibition or from
the whole feafon among them. From Ben Jonfon’s
Poetafter we learn, that one of either the performers
or proprietors had feven (hares and a half; but of what
integral fum is not mentioned. From the prices of ad¬
miflion into our ancient theatres, which have been al¬
ready mentioned, I imagine the utmoft that the (harers
of the Globe playhoufe could have received on any one
day was about 35I. So lately as the year 1685, Shad-
well received by his third day on the reprefentation of
the Squire of Alfatia, 130I.; which Downes the prompt¬
er fays was the greateft receipt that had been ever taken
at Drury-Eane playhoufe at (ingle prices. It appears
from the MSS. of Lord Stanhope, treafurer of the cham¬
bers to King James I. that the cuftomary fum paid to
VOL. XVI. Part II.
[ 641 ]
P L E
John Heminge and his company for the performance of Pkyhovife,
a play at court was twenty nobles, or fix pounds thir-, p ea
teen (hillings and four pence. And Edward Alleyn "v
mentions in his Diary, that he once had fo (lender an
audience in his theatre called the Fortune, that the whole
receipts of the houfe amounted to no more than three
pounds and feme odd (hillings.
“ Thus fcanty and meagre were the apparatus ar.d
accommodations of our ancient theatres, on which thofe
dramas were firft exhibited, that have fince engaged the
attention of fo many learned men, and delighted (o many
thoufand fpedlators. Yet even then, we are told by a
writer of that age, ‘ that dramatic poefy was fo lively
expreffed and reprefented on the public ftages and theatres
of this city, as Rome in the age of her pomp and glory
never faw it better performed; in refpecft of the adlion
and art, not of the coft and fumptuoufnefs.”
PLEA, in Law, is what either party alleges for him-
felfin court, in a caufe there depending ; and in a more
reftrained fenfe, it is the defendant’s anfwer to the plain¬
tiff’s declaration.
Pleas are ufually divided into thofe of the crown and
common pleas. Pleas of the crown are all fuits in the
king’s name, or in the name of the attorney-general in
behalf of the king, for offences committed againft his
crown and dignity, and againft his peace $ as treafon,
murder, felony, &c. See Arraignment.
Common pleas are fuch fuits as are carried on be- Biackjl.
tween common perfons in civil cafes. Thefe pleas are Comment.
of two forts ; dilatory pleas, and pleas to the aElion. Di¬
latory pleas are fuch as tend merely to delay or put off
the fuit, by queftioning the propriety of the remedy, ra¬
ther than by denying the injury : pleas to the attion are
fuch as difpute the very caufe of fuit.
I. Dilatory pleas are, 1. To the jurifdi&ion of the
court: alleging, that it ought not to hold plea of this
injury, it arifing in Wales or beyond fea : or becaufe
the land in queftion is of ancient demefiie, and ought
only to be demanded in the lord’s court, &c. 2. To
the difability of the plaintiff, by reafon whereof he is in¬
capable to commence or continue the fuit ; as, that
he is an alien enemy, outlawed, excommunicated, at¬
tainted of treafon or felony, under a praemunire, not in
rerum natura (being only a fiftitious perfon), an infant,
a feme-covert, or a monk profeffed. 3. In abatement:
which abatement is either of the writ, or the count, for
fome defied in one of thein ; as by mifnaming the defen¬
dant, which is called a mijhomer ; giving him a wwong
addition, as efquire inftead of knight ; or other want of
form in any material refped. Or, it may be that the
plaintiff is dead ; for the death of either party is at once
an abatement of the fuit.
Thefe pleas to the jurifdi&ion, to the difability, or in
abatement, w’ere formerly very often ufed as mere dila¬
tory pleas, without any foundation in truth, and calcu¬
lated only for delay •, but now by flat. 4 & 5 Ann. c. 16.
no dilatory plea is to be admitted without affidavit made
of the truth thereof, or fome probable matter (hown to
the court to induce them to believe it true. And with
refped to the pleas themfelves, it is a rule, that no ex¬
ception (hall be admitted againft a declaration or wwit,
unlefs the defendant will in the fame plea give the plain¬
tiff a better j that is, (how him how it might be amend¬
ed, that there may not be two objedfions upon the fame
account.
4 M
All
P L E
All fleas to the jurifdi&ion conclude to the cogni¬
zance of the court; praying “ judgement whether the
court will have farther cognizance of the fiut.'’ Pleas
to the difability conclude to the perfon 5 by praying
iudnement, if the faid A the plaintiff ought to be an-
fwered And pleas in abatement (when the fuit is by
original) conclude to the writ, or declaration 5 by pray¬
ing 44 judgement of the writ, or declaration, and that the
fame may be quafhed,” cajfetur, made void, or abated :
but if the aftion be by bill, the plea muft pray 44 judge¬
ment of the bill,” and not of the declaration ; the bill
being here the original, and the declaration only a copy
of the bill. r .
When thefe dilatory pleas are allowed, the cauie is
either difmilfed from that jurifdiftion, or the plaintiff is
flayed till his difability be removed } or he is obliged to
fue out a new writ, by leave obtained from the court,
or to amend and new-frame his declaration. . But when,
on the other hand, they are overruled as frivolous, the
defendant has judgement of refpondeat oujler, or to an-
fwer over in fome' better manner. It is then incumbent
on him to plead.
2. A plea to the action ; that is, to anfwer to the me¬
rits of the complaint. This is done by confefllng or de-
nying it. . . r
A confeffion of the whole complaint is not very ulual;
for then the defendant would probably end the matter
fooner, or not plead at all, but fuffer judgement to go
by default. Yet fometimes, after tender and refufal of
a debt, if the creditor haraffes his debtor with an adlion,
it then becomes neceffary for the defendant to acknow¬
ledge the debt, and plead the tender ; adding, that he
has^ always been ready, tout temps prijl, and isftill ready,
uncore prijl, to difcharge it: for a tender by the debtor
and refufal by the creditor will in all cafes difcharge the
cofts, but not the debt itfelf; though in fome particular
cafes the creditor will totally lofe his money. But fre¬
quently the defendant confeffes one part of the complaint
(by a cognovit aBionem in refpeft thereof), and traverfes
ordenies the reft ; in order to avoid the expence of car¬
rying that part to a formal trial, which he has no ground
to litigate. A. fpecies of this fort of confeftion is tne
payment of money into court: which is for the moft part
neceffary upon pleading a tender, and is itfelf a kind of
tender to the plaintiff-, by paying into the hands of the
proper officer of the court as much as the defendant ac¬
knowledges to be due, together with the cofts hitherto
incurred, in order to prevent the expence of any farther
proceedings. This may be done upon what is called a
motion ; which is an cccafional application to the court
by the parties or their counfel, in order to obtain, fome
rule or order of court, which becomes neceffary in the
progrefs of a caufe : and it is ufually grounded upon an
affidavit (the perfect tenfe of the verb affido), being a
vountary oath before fome judge or officer of the court,
to evince the truth of certain fafts, upon which the mo¬
tion is grounded : though no fuch affidavit is neceffary
for payment of money into court. If, after the money is
paid in, the plaintiff proceeds in his fuit, it is at his own
peril : for if he does not prove more due than is fo paid
into court, he {hall be nonfuited and pay the defendant’s
cofts but he (hall ftill have the money fo paid in, for
that the defendant has acknowledged to be his due. To
this head may alfo be referred the pra&ice of what is
called a Jet off; whereby the defendant acknowledges
P L E
the juftice of the plaintiff’s demand on the one hand j plea,
but on the other, fets up a demand of his own, to coun- —w
terbalance that of the plaintiff, either in the whole or in
part; as, if the plaintiff fues for ten pounds due on a
note of hand, the defendant may fet off nine pounds due
to himfelf for merchandife fold to the plaintiff; and, in
cafe he plead fuch fet-off, muft pay the remaining ba¬
lance into court.
Pleas that totally deny the caufe of complaint are ei¬
ther the general iffue, or a fpecial plea in bar.
j. The general JJae, or general plea, is what traverfes,
thwarts, and denies at once, the whole declaration, with¬
out offering any fpecial matter whereby to evade it. As
in trefpafs' either vi et armis, or on the cafe, 44 non cul-
pahilis, not guilty j” in debt upon contract, 44 nihil debet,
he ow?es nothingin debt on bond, non ejl facium,
it is not his deed on an affiumpfit, 44 non affiumpfit, he
made no fuch promife.” Or in real .addons, 44 nul torty
no wTrong done ; nul diffeijin, no diffeiftn and in a
writ of right, the mife or iffue is, that 44 the tenant has
more right to hold than the demandant has to demand.”
Thefe pleas are called the general iffue, becaufe, by im¬
porting an abfolute and general denial of what is alleged
in the declaration, they amount at once to an iffue;
by which we mean a fa£t affirmed on one fide and def
nied on the other.
2. Special pleas in bar of the plaintiff’s demands are
very various, according to the circumftances of the de¬
fendant’s cafe. As, in real aclions, a general releafe
or a fine; both of which may deftroy and bar tne plain¬
tiff’s title. Or, in perfonal actions, an accord, arbitra¬
tion, conditions performed, nonage of the defendant,
or fome other fa& which precludes the plaintiff from his
aftion. A jufification is likewife a fpecial plea in bar;
as in actions of' affault and battery,.^;/ qffault demefne,
that it was the plantiff’s own original affault.-, in tref-
pafs, that the defendant did the thing complained of in
right of fome office which warranted him fo to do ; or,
in an adion of {lander, that the plaintiff is really as bad
a man as the defendant faift he was. ...
Alfo a man may plead the ftatutes of limitation m
bar ; or the time limited by certain adls of pailiament,
beyond which no plaintiff can lay his caufe of aftion.
This, by the ftatute of 32 Hen. VIII. c. 2. in a writ
of right'is 60 years : in affizes, writs of entry, or other
poffeffory aftions real, of the feifm of one’s anceftors
in lands; and either of their feifm, or one’s own, m
rents, fuits, and fervices, 5c years: and in a6fions real
for lands grounded upon one’s own feifin or poffeflion,
fuch poffeffion muft have been within 30 years. By
ftatute 1 Mar. ft. 2. c. 5. this limitation does not extend
to any fuit foi avowfons. But by the ftatute 21 Jac. I.
c. 2. a time of limitation was extended to the cafe of
the king ; viz. 60 years precedent to 19th Feb. 1623 ;
but, this becoming ineffectual by efflux ot time, the h.me
date of limitation w'as fixed by ftatute 9 Geo. III. c. 16.
to commence and be reckoned backwards, Irom i ie
time of bringing any fuit or other procefs to recover t le
thing in queftion ; fo that a poffeflion for 60 years is
now a bar even againft the prerogative, in derogation
of the ancient maxim, Nullum ternpus occurnt regi. . y
another ftatute, 21 lac. I. c. 16. 20 years is the time
of limitation in any writ of formedon: and, by a conle-
quence, 20 years is alfo the limitation in every action
of ejeftment; for no ejeament can be brought, unkis
[ 64."
A
P L E [ 643 ] P L E
where the leffor of the plantxff is entitled to enter on
■“ the lands, and by the ftatute 21 Jac. I. c. 16. no entry
can be made by any man, unlefs within 20 years after
his right fhall accrue. Alfo all actions of trefpafs
Square claufum fregit, or otherwife), detinue, trover, re¬
plevin, account, and cafe (except upon accounts be¬
tween merchants), debt on fimple contraft, or for ar¬
rears of rent, are limited by the ftatute laft mentioned
to fix years after the caufe of aftion commenced : and
actions of afiault, menace, battery, mayhem, and impri-
fonment, muff be brought within four years, and actions
for words two years, after the injury committed. And
by the ftatute 31 Eliz. c. 5. all fuits, indiftments, and
informations, upon any penal ftatutes, where any for-
leiture is to the crown, fhall be fued within two years,
and where the forfeiture is to a fubjeft, within one
year, after the offence committed, unlefs where any
other time is fpecially limited by the ftatute. Laftly,
by ftatute 10 \V. III. c. 14. no writ of error, fare fa¬
cias, or other fuit, fhall be brought to reverfe any judge¬
ment, fine, or recovery, for error, unlefs it be profecut-
ed within 20 years. The ufe of thefe ftatutes of limi¬
tation is to preferve the peace of the kingdom, and to
prevent thofe innumerable perjuries which might enfue
if a man were allowed to bring an a£Hon for any injury
committed at any diftance of time. Upon both thefe
accounts the law therefore holds, that intereji reipublicce
ut fit finis litium: and upon the fame principle the A-
thenian laws in general prohibited all actions where the
injury was committed five years before the complaint
was made. If therefore, in any fuit, the injury, or
caufe of aftion, happened earlier than the period ex-
prefsly limited by law, the defendant may plead the
ftatutes of limitations in bar : as upon an affumpfit, or
promife to pay money to the plaintiff, the defendant
may plead, Non affumpfit infra fex annos, He made no
fuch promife within fix years; which is an effectual bar
to the complaint.
An efioppel is likewife a fpecial plea in bar \ which
happens wdiere a man hath done fome aft, or executed
fome deed, which eftops or precludes him from averring
any thing to the contrary. As if a tenant for years
(who hath no freehold) levies a fine to another perfon.
Though this is void as to ftrangers, yet it fhall work as
an eftoppel to the cognizor ; for, if he afterwards brings
an action to recover thefe lands, and his fine is pleaded
againft him, he fhall thereby be eftopped from faying,
that he had no freehold at the time, and therefore was
incapable of levying it.
The conditions and qualities of a plea (which, as well
as the doftrine of eftoppels, will alfo hold equally, nm-
tatis mutandis, with regard to other parts of pleading),
are, 1. That it be fingle and containing only one mat¬
ter 5 for duplicity begets confufion. But by ftatute 4
and 5 Ann. c. 16. a man, with leave of the court, may
plead two or more diftinft matters or fingle pleas; as in
an aftion of affault and battery, thefe three, Not guilty,
fonr affault demefne, and the ftatute of limitations.
2. I hat it be direft and pofitive, and not argumenta¬
tive. 3. That it have convenient certainty of time,
place, and perfons. 4. That it anfwer the plaintiff’s
allegations in every material point. 5. That it be fo
pleaded as to be capable of trial.
Special pleas are ufually in the affirmative, fometimes
in the negative, but they always advance fome new faft
not mentioned in the declaration j and then they muft Hea*
be averi ed to be true in the common form :—“ And 'r~“'
this he is ready to verify.”—This is not neceffary in
pleas of the general iffue, thofe always containing a to¬
tal denial of the fafts before advanced by the other par¬
ty, and therefore putting him upon the proof of them.
See Pleadings.
Plea to IndiBment, the defenfive matter alleged by a Blackft.
criminal on his indiftment; (fee Arraignment.) This
is either, 1. A plea to the jurifdiftion 2. A demurrer ;
3. A plea in abatement ; 4. A fpecial plea in bar; or,
5. The general iffue.
I. A plea to the jurifdiSiion, is where an indiftment
is taken before a court that hath no cognizance of the
offence; as if a man be indifted for a rape at the fheriff’s
tourn, or for treafon at the quarter-feffions : in thefe or
fimilar cafes, he may except to the jurifdifticn of the
court, without anfwering at all to the crime alleged.
II. A demurrer to the indiftment, is incident to cri¬
minal cafes, as well as civil, when the faft as alleged is
allowed to be true, but the prifoner joins iffue upon
fome point of law in the indiftment, by which he infifts,
that the faft, as ftated, is no felony, treafon, or what¬
ever the crime is alleged to be. Thus, for inftance, if
a ‘man be indifted for felonioufly ftealing a greyhound ;
which is an animal in which no valuable property can
be had, and therefore it is not felony, but only a civil
trefpafs to fteal it; in this cafe the party indifted may
demur to the indiftment ; denying it to be felony,
though he confefles the aft of taking it. Some have
held, that if, on demurrer, the point of law be adjudged
againft the priioner, he ffiall have judgement and exe¬
cution, as if convifted by verdift. But this is denied
by others, who hold, that in fuch cafe he fhall be di¬
rected and received to plead the general iffue, Not guil¬
ty, after a demurrer determined againft him. Which
appears the more reafonable, becaufe it is clear, that if
the prifoner freely difcovers the faft in court, and refers
it to the opinion of the court whether it be felony or
no ; and upon the faft thus fhown, it appears to be
felony, the court will not record the confeffion, but ad¬
mit him afterwards to plead not guilty. And this feems
to be a cafe of the fame nature, being for the moft part
a miftake in point of law, and in the conduft of his
pleading ; and, though a man by mifpleading may in
fome cafes lofe his property, yet the law will not fuffer
him by fuch niceties to lofe his life. However, upon
this doubt, demurrers to indiftments are feldom ufed:
fince the fame advantages may be taken upon a plea of
not guilty ; or afterwards, in arreft of judgement, when
the verdift has eftabliffied the faft.
III. A plea in abatement is principally for a mifnomer,
a wrong name, or a falfe addition to the prifoner. As,
if James Allen, gentleman, is indifted by the name of
John Allen, efquire, he may plead that he has the name
of James, and not of John ; and that he is a gentleman,
and not an efquire. And, if either faft is found by a
jury, then the indiftment ffiall be abated, as writs or
declarations may be in civil actions. But, in the end,
there is little advantage accruing to the prifoner by
means of thefe dilatory pleas ; becaufe, if the exception
be allowed, a new bill of indiftment may be framed, ac¬
cording to what the prifoner in his plea avers to be his
true name and addition. For it is a rule, upon all pleas
in abatement, that he xvho takes advantage of a flaw,
4 M 2 muft
P L E
[ 644 ]
P L E
muft at the fame time fhow how it may be amended.
Let us therefore next confider a more fubftantial kind
of plea, viz.
IV. Special pleas in bar; which go to the merits of
the indifiment, and give a reafon why the prifoner ought
not to anfwer it at all, nor put himfelf upon his trial for
the crime alleged. Thefe are of four kinds: a former
acquittal, a former conviction, a former attainder, or a
pardon. There are many other pleas which may be
pleaded in bar of an appeal : but thefe are applicable to
both appeals and indictments.
1. Firlt, the plea of aut erf cits acquit, or a former ac¬
quittal, is grounded on this univerfal maxim of the com¬
mon law of England, that no man is to be brought in¬
to jeopardy pf his life, more than once, for the fame of¬
fence. And hence it is allowed as a confequence, that
when a man is once fairly found not guilty upon any in¬
dictment, or other profecution, before any court having
competent jurifdiCtion of the offence, he may plead fuch
acquittal in bar of any fubfequent accufation for the fame
crime.
2. Secondly, the plea of auterfoits convict, or a former
conviction for the fame identical crime, though no
judgement rvas ever given, or perhaps will be (being
fulpended by the benefit of clergy or other caufes), is a
good plea in bar to an indictment. And this depends
upon the fame principle as the former, that no man
ought to be twice brought in danger of his life for one
and the fame crime.
3. Thirdly, the plea of auterfoits attaint, or a former
attainder, is a good plea in bar, whether it be for the
fame or any other felony. For wherever a man is at¬
tainted of felony, by judgement of death either upon a
verdiCt or confedion, by outlawry, or heretofore by ab¬
juration, and whether upon an appeal or an indictment •,
he may plead fuch attainder in bar to any fubfequent
indictment or appeal, for the fame or for any other fe¬
lony. And this becaufe, generally, fuch proceeding on
a fecond profecution cannot be to any purpofe ; for the
prifoner is dead in law by the firft attainder, his blood
is already corrupted, and he hath forfeited all that he
had : fo that it is abfurd and fuperfluous to endeavour
to attaint him a fecond time. Though to this general
rule, as to all others, there are fome exceptions 5 where¬
in, ccjfante ratione, ceffat et ipfa lex.
4. Laftly, a pardon may be pleaded in bar *, as at once
deftroying the end and purpofe of the indictment, by re¬
mitting that punifhment, which the profecution is cal¬
culated to intliCt. There is one advantage that attends
pleading a pardon in bar, or in the arreft of judgement
before fentence is paft; which gives it by much the pre¬
ference to pleading it after fentence or attainder. This
is, that by flopping the judgement it flops the attainder,
and prevents the corruption of the blood : which, when
once corrupted by attainder, cannot afterwards be re-
flored otherwife than by aft of parliament.
V. The generalijfue, or plea of not guilty, upon which
plea alone the prifoner can receive his final judgement of
death. ^ In cafe of an indiftment of felony or tieafon,1
there can be no fpecial juflification put in by way of
plea. As, on an indiftment for murder, a man cannot
plead that it was in his own defence againft a robber on
the highway, or a burglar ; but he mufl plead the ge¬
neral iffue, Not guilty, and give this fpecial matter in
evidence. For (befides that thefe pleas do in efxeft a-
mount to the general iffue ; fince, if true, the prifoner
is moft clearly not guilty) as the fafts in treafon are laid
to be done proditorie et contra ligeantice face debitum ;
and, in felony, that the killing was done ftlonice ; there
charges, of a traiterous or felonious intent, are the points
and very gif of the indiftment, and muft be anfwered
direftly, by the general negative, Not guilty ; and the
jury upon the evidence will take notice of any defenfive
matter, and give their verdift accordingly as efl'eftually
as if it were or could be fpecially pleaded. So that this
is, upon all accounts, the moft advantageous plea for
the prifoner.
When the prifoner hath thus pleaded not guilty, non
culpahilis, or nient culpable : which was formerly ui'ed to
be abbreviated upon the minutes, thus, Non (or nient)
cul. the clerk of the afiize, or clerk ot arraigns, on be¬
half of the crown, replies, that the prifoner is guilty, and
that he is ready to prove him fo. This is done by twro
monofyllables in the fame fpirit of abbreviation, {cul.
prit.: which fignifies firft that the prifoner is guilty,
{cul. culpable, or culpabilud) ; and then that the king is
ready to prove him fo, (prit, prcefto fum, or paratus, ve-
nfcare'). By this replication the king and the prifoner
are therefore at iffue : for when the parties come to a
faft which is affirmed on one fide and denied on the
other, then they are faid to be at iffue in point of faft :
which is evidently the cafe here, in the plea of non cul.
by the prifoner ; and the replication of cul. by the clerk.
How the courts came to exprefs a matter of this im¬
portance in fo odd and obfcure a manner, can hardly be
pronounced with certainty. It may perhaps, however,
be accounted for by luppofing, that thefe were at firft
ffiort notes, to help the memory of the clerk, and re¬
mind him what he was to reply ; or elfe it was the ffiort
method of taking down in court, upon the minutes, the
replication and averment} cul. prit: which afterwards
the ignorance of fucceeding clerks adopted for the very
words to be by them fpoken (a).
But however it may have arifen, the joining of iffue
feems to be clearly the meaning of this obfcure expref-
fion; which has puzzled our moft ingenious etymolo-
gifts, and is commonly underftood as if the clerk of the
arraigns, immediately on plea pleaded, had fixed an op¬
probrious name on the prifoner, by afking him, u culprit,
how wilt thou be tried ?” for immediately upon iffue
joined it is inquired of the prifoner, by what trial he will
make his innocence appear. This form has at prefent
reference to appeals and approvements only, wherein the
appellee has his choice, either to try the accufation by
Battle
(a} Of this ignorance wTe may fee daily inftances, in the abufe of twro legal terms of ancient I'rench : one the
prologue to all proclamations, “ Oye%, or Hear ye,” which is generally pronounced, moft unmeaningly, “ O yes:
the other, a more pardonable miftake, viz. when a jury are all fvvorn, the officer bids the crier number them, for
which the word in lawT-French is, “ Counter but we now hear it pronounced in very good Englilh, “ Count
thefe.”
P L E f ^>45
Flea, Eattle or by Jury. But upon indiftments, iince the
, ' 'a ngs' abolition of Ordeal, there can be no other trial but by
jury, per pais, or by the country: and therefore, if the
pnioner relufes to put himleli upon the inqueft in the
ufual form, that is, to anuver that he will be tried by
God and the country, if a commoner -, and, if a peer,
by God and his peers the indidfment, if in treafon, is
taken />rc confejjo ; and the prifoner, in cafes of felony,
is judged to Hand mute, and, if he perfeveres in his ob-
flinacy, fiiall now be convidled of the felony.
W hen the prifoner has thus put himfelf upon his trial,
the. clerk anfwers in the humane language of the law,
which always hopes that the party’s innocence rather
than his guilt may appear, “ God fend thee a good deli¬
verance.’3 And then they proceed, as foon as conve¬
niently may be, to the trial. See the article Trial.
ELEADINGS, in Law, are the mutual altercations
between the plaintiff and defendant, (fee Suit, Writ,
and Process). Ihey form the third part or flage of
a jadrf; and at prefent are fet down and delivered into
the proper office in writing, though formerly they were
ufuaily put in by their counfel ore tenvs, or viva voce,
in court, and then minuted down by the chief clerks or
prothonotaries ; whence, in our old law-French, the
pleadings are frequently denominated the parol.
i he tirif of thefe is the declaration, narratio, or count,
anciently called the tale; in which the plaintiff fets forth
his caufe of complaint at length : being indeed only an
amplification or expofition of the original writ upon
which his adlion is founded, with the additional circum-
Ilances of time and place, when and where, the injury
was committed.
In local actions, where poffeffion of land is to be re¬
covered, or damages for an aftual trefpafs, or for w^afte,
&c. affedling land, the plaintiff muff lay his declara¬
tion, or declare his injury to have happened in the very
county and place that it really did happen ; but in tranf-
itonj aftions, for injuries that might have happened
anywhere, as debt, detinue, Hander, and the like, the
plaintifl may declare in what county he pleafes, and
then the trial muff be in that county in which the de¬
claration is laid. Though, if the defendant wfill make
affidavit that the caufe of aflion, if any, arofe not in
that but another county, the court wfill direft a change
of the venue or vifne (that is, the vicinia or neighbour¬
hood in which the injury is declared to be done), and
w ill oblige the plaintiff to declare in the proper county.
For the ftatute 6 Rie. II. c. 2. having ordered all wuits
to be laid in their proper counties, this, as the judges
conceived, impowered them to change the venue, if re¬
quired, and not to infill rigidly on abating the writ:
which practice began in the reign of James I. And
this powrer is difcretionally exercifed, fo as not to caufe
but prevent a defect of juftice. Therefore the court
will not change the venue to any of the four northern
counties previous to the fpring circuit; becaufe there
the affifes are holden only once a-year, at the time of
lummer circuit. And it wfill fometimes remove the
venue from the proper jurifdidtion (efpecially of the
narrow and limited kind), upon a fuggeftion, duly
fupported, that a fair and impartial trial cannot be had
therein.
It is generally ufual, in aflions upon the cafe, to fet
forth feveral cafes, by different counts in the fame de¬
claration ; fo that if the plaintiff fails in the proof of
] P L E
one, he may fucceed in another. As in an aflion on
the cafe upon an assumpsit for goods fold and deliver¬
ed, the plaintiff ufuaily counts or declares, firft, upon
a fettled and agreed price betw-een him and the defend¬
ant; as, that they bargained for 201. : and left he
fhould fail in the proof of this, he counts likewfife upon
a quantum valebant; that the defendant bought other
goods, and agreed to pay him fo much as they were
reafonably worth : and then avers that they were
worth other 2o 1. and fo on in three or four different
fhapes ; and at laft concludes with declaring, that the
defendant had refufed to fulfil any of thele agreements,
whereby he is endamaged to fuch a value. And if he
proves the cafe laid in any one of his counts, though he
fails in the reft, he fhall recover proportionable da¬
mages. This declaration always concludes with thefe
W’ords, “ and thereupon he brings fait,” &c. inde pro-
ducit feciam, <b'c. By which words, fuit or feEla (a fe-
quendo), were anciently underftood the witneffes or fol¬
lowers of the plaintiff. For in former times, the law
would not put the defendant to the trouble of anfwering
the charge till the plaintiff had made out at leait a pro¬
bable cale. But the aftual production of the fuit,fedla,
°t followers, is nowT antiquated, and hath been totally
dilufed, at leaft ever fince the reign of Edward Ilf,
though the form of it ftill continues.
At the end of the declaration are added alfo the
plaintiff’s common pledges of profecution, John Doe:
and Richard Roe; which, as we elfewhere obferve,
(fee Writ), are now mere names of form; though
formerly they w-ere of ufe to anfwer to the king for the
amercement of the plaintiff, in cafe he were nonfuited,
barred of his aClion, or had a verdict and judgment
againfl: him. For if the plaintiff negleCts to deliver a
declaration for twro terms after the defendant appears, or
is guilty of other delays or defaults againft the rules of
law in any fubfequent ftage of the aftion, he is adjudged
not to follow- or purfue his remedy as he ought to do ;
and thereupon a nonfuit, or non profequiiur, is entered,
and he is find to be non-pros\\. And for thus deferting
his complaint, after making a falfe claim or complaint
(pro falfo clamore fuo), he ffiall not only pay cofts to
the defendant, but is liable to be amerced to the king,
A retraxit differs from a nonfuit, in that the one is ne¬
gative and the other pofitive : the nonfuit is a default
and neglecft of the plaintiff, and therefore he is allowed
to begin his fuit again upon payment of cofts ; but a re¬
traxit is an open and voluntary renunciation of his fuit
in court ; and by this he for ever lofes his aCtion. A-
difcontinuance is fomew-hat fimilar to a nonfuit; for w-hen
a plaintiff leaves a chafm in the proceedings ofhiscaule,
as by not-continuing the procefs regularly from day to
day, and time to time, as he ought to do, the fuit is
difeontinued, and the defendant is no longer bound to
attend ; but the plaintiff mull begin again, by filing out
a new original, ufually paying colts to his antagonift.
When the plaintiff hath Hated his cafe in the declara¬
tion, it is incumbent on the defendant, within a reafon-
able time, to make his defence, and put in a plea ; or
elie the plaintiff will at once recover judgment by de¬
fault, or nihil dick, of the defendant.
Defence, in its true legal fenfe, fignifies not a iufti-
fication, protection, or guard, which is now its popular
fignification ; but merely an oppojing or denial (from the
French verb defendre') of the truth or validity of the
complaint.
P L E
[ 646 ]
P L E
Pleadings, complaint. It is the conteftatio litis of the civilians : a
t“—v—— general affertion that the plaintiff hath no ground of
action ; which affertion is afterwards extended and main¬
tained in his plea.
Before defence made, if at all, cognizance of the
fuit muft be claimed or demanded j when any perfon
or body-corporate hath the franchife, not only of hold¬
ing pleas within a particular limited jurifdiftion, but
alfo of the cognizance of pleas ; and that either without
any words exclufive of other courts, which intitles the
lord of the franchife, whenever any fuit that belongs to
his jurifdiftion is commenced in the courts at Weftmin-
fler, to demand the cognizance thereof j or with fuch
exclufive words, wrhich alfo in title the defendant to plead
to the jurifdiftion of the court. Upon this claim of
cognizance, if allowed, all proceedings (hall ceafe in the
fuperior court, and the plaintiff is left at liberty to
purfue his remedy in the fpecial jurifdidlion. As, when
a fcholar or other privileged perfon of the univerfities
of Oxford or Cambridge is impleaded in the courts at
Weftmintter, for any caufe of aftion whatfoever, unlefs
upon a quellion of freehold. In thefe cafes, by the
charter of thofe learned bodies, confirmed by aft of par¬
liament, the chancellor, or vice-chancellor, may put in
a claim of cognizance 5 which, if made in due time and
form, and with due proof of the fafts alleged, is regu¬
larly allowed by the courts. It muft be demanded be¬
fore full defence is made or imparlance prayed \ for thefe
are a fubmiflion to the jurifdiftion of the fuperior court,
and the delay is a laches in the lord of the franchife :
and it will not be allowed if it occafions a failure of-juf-
tice, or if an aftion be brought againft the perfon him-
felf who claims the franchife, unlefs he hath alfo a power
in fuch cafe of making another judge.
After defence made, the defendant muft put in his
plea. But before he defends, if the fuit is commenced
by capias or latitat, without any fpecial original, he is
intitled to demand one imparlance, or licentia loquendi;
and may, before he pleads, have more granted by confent
of the court, to fee if he can end the matter amicably
without farther fuit, by talking with the plaintiff : a
praftice which is fuppofed to have arifen from a principle
of religion, in obedience to that precept of the gofpel,
“ agree with thine adverfary quickly, whilft thou art in
the way with him.” And it may be obferved, that this
gofpel-precept has a plain reference to the Roman law of
the twelve tables, which exprefsly direfted the plaintiff
and defendant to make up the matter while they -were
in the way, or going to the praetor *,—in via, rent uti
pacent orato. There are alfo many other previous fteps
which may be taken by a defendant before he puts in
his plea. He may, in real aftions, demand a view of
the thing in queftion, in order to afcertain its identity
and other circumftances. He may crave oyer of the
writ, or of the bond, or other fpecialty upon which the
aftion is brought-, that is, to hear it read to himj the
generality of defendants in the times of ancient fimpli-
city being fuppofed incapable to read it themfelves:
whereupon the whole is entered verbatim upon the re¬
cord -, and the defendant may take advantage of any
condition, or other part of it, not ftated in the plaintiff’s
declaration. In real aftions alfo the tenant may pray in
aid, or call for the aftiftance of another, to help him
to plead, becaufe of the feeblenefs or imbecility of his
own eftate. Thus a tenant for life may pray in aid of
him that hath the inheritance in remainder or revet- Pleadings,
fion j and an incumbent may pray in aid of the patron —y——'
and ordinary j that is, that they fhall be joined in the
aftion, and help to defend the title. Voucher alfo is the
calling in of fome perfon to anfwer the aftion, that hath
warranted the title to the tenant or defendant. This
wre ftill make ufe of in the form of common recoveries,
which are grounded on a writ of entry *, a fpecies of ac¬
tion that relies chiefly on the wTeaknefs of the tenant’s
title, who therefore vouches another perfon to warrant
it. If the voucher appear, he is made defendant in-
ftead of the voucher; but if he afterwards makes de¬
fault, recovery ihall be had againft the original defen¬
dant 5 and he fhall recover an equivalent in value againft
the deficient vouchee. In aflizes, indeed, where the
principal queftion is, whether the demandant or his an-
ceftors were or were not in poffeflion till the oufter hap¬
pened, and the title of the tenant is little (if at all) dif-
cuffed, there no voucher is allowed but the tenant may
bring a w-rit of warrantia charter againft the warrantor,
to compel him to aflift him with a good plea or defence,
or elfe to render damages and the value of the land, if
recovered againft the tenant. In many real aftions al¬
fo, brought by or againft an infant under the age of 21
years, and alfo in aftions of debt brought againft him,
as heir to any deceafed anceftor, either party may fug-
geft the nonage of the infant, and pray that the proceed¬
ings may be deferred till his full age, or, in our legal
phrafe, that the infant may have his age, and that the
parol may demur, that is, that the pleadings may be
ftaid ; and then they (hall not proceed till his full age,
unlefs it be apparent that he cannot be prejudiced there¬
by. But by the ftatutes of Weftm. 1. 3 Edw. I. c. 46.
and of Glocefter, 6 Edw. I. c. 2. in w-rits of entry fur
diffeijin in fome particular cafes, and in aftions aunce-
ftrel brought by an infant, the parol fhall not demur 5
otherwife he might be deforced of his whole property,
and even want a maintenance, till he came of age. So
likewife in a wait of dow'er the heir fhall not have his
age -, for it is neceflary that the widow’s claim be im¬
mediately determined, elfe Ihe may want a prefent fub-
fiftence. Nor Ihall an infant patron have it in a quare
impedit, fince the law holds it neceffary and expedient
that the church be immediately filled.
When thefe proceedings are over, the defendant muft
then put in his excufe or plea. See Plea.
It is a rule in pleading, that no man be allow-ed to
plead fpecially fuch a plea as amounts only to the gene¬
ral iffue, or a total denial of the charge ; but in fuch
cafe he fhall be driven to plead the general iffue in terms,
■whereby the whole queftion is referred to a jury. But
if the defendant, in an aflize or aftion of trefpafs, be
defirous to refer the validity of his title to the court
rather than the jury, he may ftate his title fpecially;
and at the fame time give colour to the plaintiff, or fup-
pofe him to have an appearance or colour of title, bad
indeed in point of law, but of which the jury are not
competent judges. As if his own true title is, that he
claims by feoffment with livery from A, by force of
which he entered on the lands in queftion, he cannot
plead this by itfelf, as it amounts to no more than the
general iffue, nultort, mildijj'eif.n, in affize, or not guilty
in an aftion of trefpafs. . But he may allege this fpe¬
cially, provided he goes farther, and fays, that the plain¬
tiff claiming by colour of a prior deed of feoffment, with¬
out
P L E
Pleaciin
gs. out livery, entered ; upon whom he entered ; and may
“■ then refer himfelf tot he judgement of the court which of
thefe two titles is the belt in point of law.
When the plea of the defendant is thus put in, if it
does not amount to an iffue or total contradiction of
the declaration, but only evades it, the plaintiff may
plead again, and reply to the defendant’s plea : Either
traverfing it, that is, totally denying it; as if, on an
aCtion of debt upon bond, the defendant pleads folvit
ad diem, that he paid the money when due ; here the
plaintiff in his replication may totally traverfe this plea,
by denying that the defendant paid it: Or he may al¬
lege new matter in contradiction to the defendant’s plea;
as'when the defendant pleads no award made, the plain¬
tiff may reply, and fet forth an aCtual award, and aflign
a breach : Or the replication may confefs and avoid the
plea, by fome new matter or diftin&ion, confiftent with
the plaintiff’s former declaration j as in an aCtion for
trefpafling upon land whereof the plaintiff is feized, if
the defendant (hows a title to the land by defcent, and
that therefore he had a right to enter, and gives colour
to the plaintiff, the plaintiff may either traverfe and
totally deny the fad of the defcent; or he may confefs
and avoid it, by replying, that true it is that fuch de¬
fcent happened, but that fince the defcent the defendant
himfelf demiied the lands to the plaintiff for term of life.
To the replication the defendant may rejoin, or put in
an anfwer called a rejoinder. The plaintiff may anfwer
the rejoinder by a fur-rejoinder; upon which the de¬
fendant may rebut, and the plaintiff anfwer him by a
fur-rebutter. Which pleas, replications, rejoinders, fur-
rejoinders, rebutters, and fur-rebutters, anfwer to the
exceptio, replicatio, duplicatio, triplicatio, and quadruplica-
tio, of the Roman laws.
The whole of this procefs is denominated the plead¬
ing; in the feveral ftages of which it muff be carefully
obferved, not to depart or vary from the title or defence
•which the party has once infilled on. For this (which
is called a departure in pleading) might occafion endlefs
altercation. Therefore the replication mult fupport the
declaration, and the rejoinder muff fupport the plea,
without departing out of it. As in the cafe of pleading
no award made in confequence of a bond of arbitration,
to which the plaintiff replies, fetting forth an adtual
award ; now the defendant cannot rejoin that he hath
performed this award, for fuch rejoinder would be an
entire departure from his original plea, which alleged that
no fuch award wTas made : therefore he has now no other
choice, but to traverfe the fa£t of the replication, or elfe
to demur upon the law of it.
Again, all duplicity in pleading muff be avoided.
Every plea muff be fimple, entire, connefted, and con¬
fined to one fingle point : it muff never be entangled
with a variety of diftincl independent anfwers to the
fame matter ; which muff require as many different re¬
plies, and introduce a multitude of iffues upon one and
the fame difpute. For this wmuld often embarrafs the
jury, and fometimes the court itfelf, and at all events
would greatly enhance the expence of the parties. Yet
it frequently is expedient to plead in fuch a manner as
to avoid any implied admiflion of a fa£f, which cannot
with propriety or fafety be pofitively affirmed or denied.
And this may be done by what is called a protejlation ;
whereby the party interpofes an oblique allegation or
denial of fome faft, proteffing (by the gerund, protefan-
[ <47 1
P L E
doj that fuch a matter does or does not exiff ; and at Pleadings,
the fame time avoiding a diredt affirmation or denial.
Sir Edward Coke hath defined a proteftation (in the
pithy dialect of that age) to be, “ an exclufion of a
conclufion,” For the ufe of it is, to fave the party
from being concluded with vefpedt to fome fadt or cir-
cumltance which cannot be diredtly affirmed or denied
without falling into duplicity of pleading ; and which
yet, if he did not thus enter his proteft, he might be
deemed to have tacitly waved or admitted. Thus, while
tenure in villainage fubfifted, if a villain had brought an
adlion againft his lord, and the lord was inclined to try
the merits of the demand, and at the fame time to pre¬
vent any conclufion againft himfelf that he had waved
his figniory ; lie could not in this cafe both plead affir¬
matively that the plaintiff was his villain, and alfo take
iffue upon the demand ; for then his plea would have
been double, as the former alone would have been a good
bar to the aiffion : but he might have alleged the villai¬
nage of the plaintiff by way of proteftation, and then
have denied the demand. By this means the future vaf-
falage of the plaintiff'was faved to the defendant, in cafe
the iffue w^as found in his (the defendant’s) favour; for
the proteftation prevented that conclufion which would
otherwife have refulted from the reft of his defence,
that he had enfranchifed the plaintiff, fince no villain
could maintain a civil aftion againft his lord. So alfo
if a defendant, by way of inducement to the point of his
defence, alleges (among other matters) a particular mode
of feifin or tenure which the plaintiff is unwilling to
admit, and yet defires to take iffue on the principal
point of the defence, be muft deny the feifin or tenure
by way of proteftation, and then traverfe the defenfive
matter. So, laftly, if an award be fet forth by the
plaintiff, and he can affign a breach in one part of it
(viz. the non-payment of a fum of money), and yet is
afraid to admit the performance of the reft of the award,
or to aver in general a non-performance of any part of
it, left fomething fliould appear to have been performed ;
he may fave to himfelf any advantage he might hereafter
make of the general non-performance, by alleging that
by proteftation, he can plead only the non-payment of the
money.
In any ftage of the pleadings, when either fide advan¬
ces or affirms any new matter, he ufually (as was faid)
avers it to be true ; “ and this he is ready to verify.”
On the other hand, when either fide traverfes or denies
the fafts pleaded by his antagonift, he ufually tenders an
iffue, as it is called \ the language of which is different
according to the party by whom it is tendered : for if
the traverfe or denial comes from the defendant, the if¬
fue is tendered in this manner, “ And of this he puts
himfelf upon the country,” thereby fubmitting himfelf to
the judgement of his peers : but if the traverfe lies upon
the plaintiff, he tenders the iffue or prays the judgement
of the peers againft the defendant in another form; thus,
“ and this he prays may be inquired of by the coun¬
try.”
But if either fide (as, for inftance, the defendant)
pleads a fpecial negative plea, not traverfing or denying
any thing that was before alleged, but difclofing fome
new negative matter ; as where the fuit is on a bond
conditioned to perform an award, and the defendant,
pleads, negatively, that no award was made ; he tenders
no iffue upon this plea, becaufe it does not yet nppear
whether
P L E r 648 1 P L E
Pleadings, whether the fact will be difputed, the plaintiff not hav-
t'leafare. :ri^ yet afferted the exiftence of any award : but when
^ the plaintiff replies, and fets forth an a£iual fpecific
award, if then the defendant traverfes the replication,
and denies the making of any fuch award, he then, and
not before, tenders an iffue to the plaintiff. For when
in the courfe of pleading they come to a point which is
affirmed on one fide and denied on the other, they are
then faid to be at iffue ; all their debates being at lafi:
concrafted into a fingle point, which rnuft now be de¬
termined either in favour of the plaintiff or of the defen¬
dant. See Issue.
PLEASING, art of. See Politeness.
PLEASURE is a word fo univerfally underftood as
to need no explanation. Lexicographers, however, -who
muff attempt to explain every word, call it “ the grati¬
fication of the mind or fenles.” It is direftly oppofite
to Pain, and confiitutes the whole of pofitive happinefs,
ns that does of mifery.
The Author of Nature has furnifined us with many
pleafures, as well as made us liable to many pains 5 and
ive are fufceptible of both in fome degree as foon as avc
w F-ncyclo- have life and are endowed with the faculty of fenfation.
pedie Me- pYench writer, in a work * which once raifed high
tj^ruiue exPe^a!;ions) contends, that a child in the Avomb of its
Metaphy- mother feels neither pleafure nor pain. “ Thefe fen-
f.que,cx. fations (fays he) are not innate 5 they have their origin
Morale, from without 5 and it is at the moment of our birth that
.om. xv. t-jle receives the firft impreffions ; impreffions flight
and fuperficial at the beginning, but Avhich by time and
repeated a£ts leave deeper traces in the fenforium, and
become more extenfive and more lafting. It is when
the child fends forth its firft cries that fenfibility or the
faculty of fenfation is produced, which in a fhort time
gathers ftrength and {lability by the impreffion of exte¬
rior objefls. Pleafure and pain not being innate, and
being only acquired in the lame manner as the qualities
which we derive from inftruffion, education, and fociety,
it follows that avc learn to fuffer and enjoy as we learn
any other fcience.”
This is {{range reafoning and flrange language. That
fenfations are not innate is univerfally acknoivledged ;
but it does not therefore follow that the foul receives its
firit impreffions and firfl fenfations at the moment ©f
birth. The child has life, the powgr of locomotion,
and the fenfe of touch, long before it is born ; and
every mother will tell this philofopher, that an infant
unborn exhibits fymptoms both of pain and of plea¬
fure. That many of our organs of fenfe are improved
by ufe is incontrovertible •, but it is fo far from being
true that our fenfible pleafures become more exquifite
by being often repeated, that the direft contrary is ex¬
perienced of far the greater part of them •, and though
external objefls, by making repeated impreffions on the
fenfes, certainly leave deeper traces on the memory than
an objeft once perceived can do, it by no means folloAvs
that thefe impreffions be«ome the more delightful the
more familiar that they are to us. That we learn to
fuffer and enjoy as we learn any other fcience, is a moft
extravagant paradox ; for it is felf-e\ddent that we can¬
not live Avithout being capable in fome degree both of
fuffering and enjoyment, though a man may certainly
15\'e to old age in profound ignorance of all the fcien-
ces.
The fame writer affures us, indeed, that fenfation is
3
not neceffary to human life. “ Philofophers (fays he) PI
make mention of a man who had loll every kind of feel¬
ing in every member of his body : he was pinched or
pricked to no purpofe. Meanwhile this man made ufe
of all his members •, he Avalked without pain, he drank,
ate, and fiept, without perceiving that he did fo. Sen-
fible neither to pleafure nor pain, he was a true natural
machine.”
To the tale of thefe anonymous philofophers our au¬
thor gives implicit credit, whilft he favours us at the
fame infiant with the following argumentation, which
completely proves its falfehood. “ it is true that fen¬
fation is a relative quality, fufceptible of increafe and
diminution j that it is not neceffary to exiilence ; and
that one might live without it: but in this cafe he would
live as an automaton, without feeling plealure or pain j
and he Avould poffefs neither idea, nor reflection, nor de¬
fire, nor paffion, nor will, nor fentiment •, his exiitence
would be merely paffive, he would live without knowing
it, and die without apprehenfion.”
But if this man of the philofophers, whom our au¬
thor calls an automaton, and a true natural machine, had
neither idea, nor defire, woxpajjion, nor veil!, norfentiment
(and without fenfation he certainly could have none of
them), Avhat induced him to voalh, eat, or drink, or to
ceafe from any oi thefe operations after they Avere ac¬
cidentally begun ? The inftances of the automata which
played on the flute and at chefs are not to the purpofe
for which they are adduced j for there is no parallel
betAveen them and this natural machine, unlefs the phi¬
lofophers Avound up their man to eat, drink, Avalk, or
fit, as Vacanfon and Kempeler wound up their automa¬
ta to play or ceafe from playing on the German flute
and at chefs. See Aneroides.
Our author having for a while fported with thefe
harmlefs paradoxes, proceeds to put the credulity of his
reader to the teft Avilh others of a very contrary ten¬
dency. He inftitutes an inquiry concerning the fupe-
riority, in number, and degree, of the pleafures enjoyed
by the different orders of men in fociety $ and labours,
not indeed by argument, but by loofe declamation, to
propagate the belief that happinefs is very unequally
diftributed. The pleafures of the rich, he fays, muff
be more numerous and exquifite than thofe of the poor j
the nobleman mufl: have more enjoyments than the ple¬
beian of equal Avealth ; and the king, according to him,
mult be the happieft of all men. He owns, indeed, that
although “ birth, rank, honours, and dignity, add to
happinefs, a man is not to be confidered as miferable
becaufe he is born in the lower conditions of life. A man
may be happy as a mechanic, a merchant, or a labourer,
provided he enters into the fpirit of his profeffion, and
has not imbibed by a mifplaced education thofe fenti-
ments Avhich make his condition infupportable. Hap¬
pinefs is of eafy acquifition in the middling ftations of
life ; and though perhaps vee are unable to know or to
rate exactly the pleafure which arifes from contentment
and mediocrity, yet happinefs being a kind of aggre¬
gate of delights, of riches, and of advantages more or
lefs great, every perfon muff have a {hare of it ; the di-
vifion is not exadtly made, but all other things equal,
there wall be more in the elevated than in the inferior
conditions of fociety *, the enjoyment will he more felt,
the means of enjoying more multiplied, and the plea¬
fures more varied. Birth, rank, fortune, talents, wit,
genius.
P L E [ <549 ] P L E
Pleafure. gemus, and virtue, are then the great fources of h-appi-
nefs : thoie advantages are fo confiderable, that we, fee
men contented with any one of them, but their union
forms fupreme felicity.
“ There is fo vaft a difference, fays Voltaire, between
a man who has made his fortune and one who has to
make it, that they are fcarcely to be confidered as crea¬
tures of the fame kind. The fame thing may be faid
of birth, the greateft of all advantages in a large fo-
ciety ; of rank, of honours, and of great abilities. How
great a difference is made between a perfon of high
birth and a tradefman •, between a Newton or Defflfer-
tes and a fimple mathematician ? Ten thoufand foldiers
are killed on the field of battle, and it is fcarcely men¬
tioned ; but if the general fall, and efpecially if he be
a man of courage and abilities, the court and city are
filled wuth the news of his death, and the mourning is
univerfal.
“ Frederick the Great, king of Pruflia, felt in a
more lively manner than perhaps any other man the
value of great talents. I would willingly renounce,
faid he to Voltaire, every thing which is an object of
deure and ambition to man ; but I am certain if I were
not a prince I fliould be nothing. Your merit alone
would gain you the efteem, and envy, and admiration of
the world ; but to fecure refpecf for me, titles, and ar¬
mies, and revenues, are abfolutely neceffary.'”
For what purpofe this account of human happinefs
was publifned, it becomes not us to fay. Its obvious
tendency is to make the lower orders of fociety difcon-
tented with their date, and envious of their fuperiors 5
and it is not unreafonable to fuppofe, that it contributed
in fome degree to excite the ignorant part of the author’s
countrymen to the commiffion of thofe atrocities of which
they have fmce been guilty. That fuch rvas his inten¬
tion, the following extraft will not permit us to believe 5
for though in it the author attempts to fupport the fame
falfe theory of human happinefs, he mentions virtuous
kings with the refpedt becoming a loyal fubjeft of the
unfortunate Louis, whofe character he feems to have in¬
tentionally drawn, and whofe death by the authority of
a favage fa£lion he has in effe6t foretold.
. “ Happinefs, in a date of fociety, takes the mod va¬
riable forms : it is a Proteus fufceptible of every kind of
metamorpholis : it is different in different men, in differ¬
ent ages, and in different conditions, &c. The pleafures
of youth are very different from thofe of old age : what
affords enjoyment to a mechanic would be fupreme mi-
fery to a nobleman ; and the amufements of the country
would appear inlipid in the capital. Is there then no¬
thing fixed wfith regard to happinefs ? Is it of all things
the mod: variable and the mod arbitrary ? Or, in judg¬
ing of it, is it impodible to find a dandard by which we
can determine the limits of the greated good to which
man can arrive in the prefent date ? It is evident that
men furm the fame ideas of the beautiful and fubiime in
fiature, and of right and wrong in morality, provided
they have arrived at that degree of improvement and ci¬
vilization of which human nature is fufceptible ; and that
different opinions on thefe fubje&s depend on different
degrees of culture, of education, and of improvement.
The fame thing may be advanced with regard to happi¬
nefs all men, if equal wfith refpett to their organs,
would form the very fame ideas on this fubjeft if they
readied the degree of improvement of which we are pre-
Vol. XVI. Part II.
fently fpeaking 5 aftd in fad, do we not fee in the great
circles at Rome, at Vienna, at London, and Paris, that
thofe who are called people of falhion, who have receiv¬
ed the fame education, have nearly the fametafte, the fame
defires, and the fame fpirit for enjoyment ? there is doubt-
lefs a certain degree of happinefs to be enjoyed in every
condition of lile ; but as there are fome conditions pre¬
ferable to others, fo are there degrees of happinefs great¬
er and lefs j and if wre wTere to form an idea of the greateff
poffible in the prefent ftate, it perhaps wTould be that of
a fovereign, mafter of a great empire, enjoying good
health and a moderate fpirit) endowed with piety and
virtue ; whole wThole life was employed in ads of ju-
ffice and mercy, and wrho governed by fixed and im¬
moveable laws. Such a king is the image of the di¬
vinity on earth, and he muff be the idol of a wife
people. His whole liie fhould prefent a pidure of the
molt augult felicity. Although fuch fovereigns are
rare, yet we are not without examples of them. An¬
cient hiftory affords us Titus and Marcus Aurelius, and
the prelent age can boaft of piety and munificence in
the charader of fome of its kings. This fiate of the
greateff happinefs to which man can reach not being
ideal, it will ferve as a ftandard of coroparifun by which
happinefs and mifery can be eftimated in all civilized
countries. He is as happy as a king, is a proverbial ex-
preflion, becaufe rve believe with jultice that royalty is
the extreme limit of the greateft enjoyments 5 and in
fad, happinefs being the work of man, that condition
which comprehends all the degrees of posver and of
glory, which is the fource of honour and of dignity,
and W'hich fuppofes in the perfon inverted with it all
means of enjoyment either for himfelf or others, leaves
nothing on this earth to which any reafonable man
■would give the preference.
We can find alfo in this high rank the extreme of
the greateft evils to which the condition of nature is ex-
pofed. A king condemned to death and perifhing on a
fcaftold, by the authority of a fadion, while at the
fame time he had endeavoured by every means in his
power to promote the general happinefs of his fub-
jeds, is the moft terrible and ftriking example of human
milery } for if it be true that a crown is the greateft of
all blefiings, then the lofs of it, and at the fame time
the lofs of life by an ignominious and unjuft fentence
are of all calamities the moil dreadful.
“ It is alfo in the courts of kings that we find the
moft amiable and perfed charaders ; and it is there
where true grandeur, true politenefs, the beft tone of
manners, the moft amiable graces, and the moil emi¬
nent virtues, are completely eftablifhed. It is in courts
that men feem to have acquired their greateft improve¬
ment : Whofoever has feen a court, fays La Bruyere,
has feen the world in the moft beautiful, the moft en¬
chanting, .and attradive colours. The prejudices of
mankind in behalf of the great are fo excefljve, that if
the^ inclined to be good they would be almoft the ob-
jeds of adoration.”
In this paffage there are doubtlefs many juft obferva-
tions 5 but there is at leaft an equal number of others
both falfe and dangerous. That a crown is the greateft
of earthly bleflings, and that it is in the courts of kings
that we meet with the moft amiable and perfed charac¬
ters, are pofitions which a true philofopher will not ad¬
mit but with great limitations. The falfehood of, the
4 N author’s
Plcafure-.
f Dr Say¬
ers.
P L E [65
t'lrafire, author’s general theory refpefling the unequal dillribu-
”■ ' tion of happinefs in fociety, we need not wafte time in
e':pofirig. It is fufficiently expofed in other articles of
this work, and in one of them by a writer of a very fu-
perior order (See Happiness ; and MORAL Philofophy,
Part II. chap. ii.). He enters upon other fpeculations
xefpe£Hng the pleafures and pains of favages, which are
ingenious and worthy of attention ; but before we pro¬
ceed to notice them, it will be proper to confider the
connexion which fubfifts between pleafure and pain.
“ That the ceffation of pain is accompanied by plea¬
fure, is a fadt (fays a philofopher of the firfl rank f)
wdiich has been repeatedly obferved, but perhaps not
fufficiently accounted for. Let us fuppofe a perfon in a
Hate of indifference as to heat. Upon coming near a
fire, he will experience at firll an agreeable warmth, i. e.
pleafure. If the heat be increafed, this ftate of pleafure
wall, after a time, be converted into one of pain, from
the increafed adtion upon the nerves and brain, the un¬
doubted organs of all bodily fenfations. Let the heat
now be gradually withdrawn, the nervous fyflem mull
acquire again, during this removal, the ftate of agree¬
able warmth or plealure ; and after paffing through that
ftate it will arrive at indifference. From this fadt then
we may conclude, that a frate of pleafure may be puff¬
ed on till it is converted into one of pain ; and, on the
other hand, that an adtion which produces pain will, if
it go off gradually, induce at a certain period of its de-
creafe a Hate of pleafure. The fame reafoning which
has thus been applied to the body may be extended alfo
to the mind. Total languor of mind is not fo pleafant
as a certain degree of adtion or emotion •, and emotions
pleafant at one period may be increafed till they become
painful at another •, whilft painful emotions, as they
gradually expire, will, at a certain period of their de-
creafe, induce a ftate of pleafure. Hence then we are
able to explain why pleafure ffould arife in all cafes
from the gradual ceffation of any adtion or emotion
which produces pain.”
The fame author maintains, that from the mere re¬
moval of pain, whether by degrees or inftantaneoufty,
“we always experience pleafure ; and if the pain remo¬
ved w’as exquifite, what he maintains is certainly true.
To account for this phenomenon he lays down the fol-
lowdng law of nature, which experience abundantly con¬
firms, viz. “ that the temporary withdrawing of any ac¬
tion from the body or mind invariably renders them
more fufceptible of that adlion when again produced.”
Thus, after long falling, the body is more fufceptible of
the effedls of food than if the ftomach had been lately
fatisfied *, the adlion of llrong liquors is found to be
greater on thofe who ufe them feldom than on fuch as
are in the habit of drinking them. Thus, too, with re-
fpedl to the mind ; if a perfon be deprived for a time of
his friend’s fociety, or of a favourite amufement, the
next vilk of his friend, or the next renewal of his amufe-
ment, is attended with much more pleafure than if they
had never been wuthheld from him.
“ To apply this lawr to the cafe of a perfon fuddenly
relieved from acute pain. While he labours with fuch
pain, his mind is fo totally occupied by it, that he is
unable to attend to his cuftomary purfuits or amufe-
ments. He becomes therefore fo much more fufceptible
of their adlion, that when they are again prefented to
'him, he is railed above his ufual indifference to pofitive
o ] P L E
pleafure. But all pains do not proceed from an excefs Pbafure.
of adlion. Many of them arife from reducing the body v——v——-’
or the mind to a ftate belowr indifference. Thus, if a
perfon have juft; fufficient warmth in his body to keep
him barely at eafe or in a ftate of indifference, by with¬
drawing this heat a ftate of uneafinefs or pain is produ¬
ced 5 and if in a calm Hate of mind one be made ac¬
quainted wdth a melancholy event, his quiet is inter¬
rupted, and he links below indifference into a painful
Hate of mind. If now, without communicating any
new fource of pofitive pleafure, w e remove in the former
cafe the cold, and in the latter the grief, the perfons
from whom they are removed will experience real plea¬
fure. Thus, then, whether pain arifes from' excels or
deficiency of adlion, the gradual or the hidden removal
of it mull be in all cafes attended wuth pleafure *.” It * Bifqvijt-
is equally true that the gradual or hidden removal cfUon*
pleafure is attended with pain. ^ndLiu-
We are now prepared to examine our French author’srairy.
account of the pleafures and pains of favages. “ Every
age (fays he) has its different pleafures •, but if we v?ere
to imagine that thofe of childhood are equal to thofe of
confirmed age, we ffould be much miftaken in cur efti-
mation of happinefs. The pleafures of philofophy, ei¬
ther natural or moral, are not unfolded to the infant j
the moll perfedl mufic is a vain noife 5 the moll exqui¬
fite perfumes and diflies highly feafoned offend his
young organs inftead of affording delight •, his touch is
imperfedl ; forty days elapfe before the child gives any
fign of laughter or of wreeping ; his cries and groans
before that period are not accompanied with tears j his
countenance exprefles no paffion; the parts of his face
bear no relation to the fentiments of the foul, and are
moreover without confiltency. Children are but little
affedled with cold ; whether it be that they feel lefs, or
that the interior heat is greater than in adults. In them
all the impreffions of pleafure and pain are tranfitory ;
their memory has fcarcely begun to unfold its powers ;
they enjoy nothing but the prefent moment; they weep,
laugh, and give tones of fatisfaftion without confciouf-
nefs, or at leaff without reflexion ; their joy is confined
to the indulgence of their little whims, and conftraint is
the greateft of their misfortunes ; fewT things amufe, and
nothing fatisfies them. In this happy condition of early
infancy nature is at the whole expence of happinefs $
and the only point is not to contradift her. What de¬
fires have children ? Give them liberty in all their
movements, and they have a plenitude of exiftence, an
abundance of that kind of happinefs which is confined in
fome fort to all the objedls which furround them : but if
all beings were happy on the fame conditions, fociety
would be at no expence in procuring the happinefs of
the different individuals who compole it. Senfation is
the foundation of refleftion j it is the principal attribute
of tbe foul; it is by this that man is elevated to fublime
fpeculations, and fecures his dominion over nature and
himfelf. This quality is not ftationary, but fufceptible,
like all other relative qualities, of increafe and decay,
of different degrees of ftrength and intenfenefs : it is
different in different men ; and in the fame man it in-
creafes from infancy to youth, from youth to confirmed
manhood : at this period it flops, and gradually declines
as w7e proceed to old age and to fecond childifhnefs.
Confidered phyfically, it varies according to age, con-
ftitution, climate, and food} confidered in a moral point
of
P L E
jj'Ifiafure.^ of view, it takes its different appearances from indivi-
• dual education, and from the habits of fociety 5 for man
in a date of nature and fociety, with regard to fenfation
and the unfolding of his powers, may be confidered as
two diftindl beings : and if one were to make a calcu¬
lation of pleafure in the courfe of human life, a man of
fortune and capacity enjoys more than ten thoufand la¬
vages.
“ Pleafure and pain being relative qualities, they may
be almoft annihilated in the moment of vehement paf-
fion. In the heat of battle, for example, ardent and
animated fpirits have not felt the pain of their wounds ;
and minds ftrongly penetrated with fentiments of reli¬
gion, enthufiafm, and humanity, have fupported the
molt cruel torments with courage and fortitude. The
fenfibility of fome perfons is fo exquifitely alive, that one
can fcarcely approach them without throwing them into
convulfions. Many difeales Ihovv the effe& of fenfibility
pulhed to an extreme ; fuch as hyfteric affeftions, cer¬
tain kinds of madnefs, and fome of thofe which proceed
from poifon, and from the bite or fting of certain ani¬
mals, as the viper and the tarantula. Exceffive joy or
grief, fear and terror, have been known to deftroy all
fenfalion, and occafion death (a).”
Having made thefe preliminary obfervations on plea-
ftireand pain in infancy, and as they are increafed or
dimini (bed by education, and the different conditions of
body and mind, our author proceeds to confider the ca¬
pability of favages to feel oleafure and pain. “ By fa-
vages he underftands all the tribes of men who live by
hunting and ufiling, and on thofe things which the
earth yields without cultivation. Thofe trines who pof-
fefs herds of cattle, and who derive their fubfiftence
from fuch poffeffions, are not to be confidered as favages,
as they have fome idea of property. Some favages are
■naturally compaflionate and humane, others are cruel
and fanguinary. Although the phyfical conftitution of
man be everywhere the fame, yet the varieties of cli¬
mate, the abundance or fcarcity of natural productions,
have a powerful influence to determine the inclinations.
Even the fiercenefs of the tiger is foftened under a mild
Iky 5 now nature forms the manners of favages juft as
iociety and civil inftitutions form the manners of civili-
lized life. In the one cafe climate and food produce al¬
moft the whole effeCt; in the other they have fcarcely
any influence. The habits of fociety every moment
contend with nature, and they are almoft always victo¬
rious. The favage devotes himfelf to the dominion of
his paftions •, the civilized man is employed in reftrain-
mg, in directing, and in modifying them : fo much in¬
fluence have government, laws, fociety, and the fear of
cenfure and punilhment, over his foul.
P L E
It is not t6 be doubted that favages are fuiceptlble Plcafure.
both of pleaiuie and pain j but are the unpreflions made y
on their organs as fenfible, or do they feel pain in the
fame degree with the inhabitants of a civilized coun¬
try >
“ Their enjoyments are fo limited, that if we confine
ourfelves to truth, a few lines will be fufficient to de-
feribe them : our attention muft therefore be confined to
pain, becaufe the manner in which they fupport misfor¬
tune, and even torture, prefents us with a view of cha--
rafter unequalled in the hiftory of civilized nations. It
is not uncommon in civilized countries to fee men bra¬
ving death, meeting it with cheerfulnefs, and even not
uttering complaints under the torture; but they do not
infult the executioners of public vengeance, and defy
pain in order to augment their torments •, and thofe who
are condemned by the laws fuffer the punitinnent with
different degrees of fortitude. On thofe mournful occa-
fions, the common ranks of mankind in general die
with lefs firmnefs : thofe, on the other hand, who have
received education, and who, by a train of unfortunate
events, are brought to the fcaffbld, whether it be the
fear of being reproached wuth cowardice, or the confi-
deration that the ftroke is inevitable, fuch men difeover
the expiring fighs of felf-love even in their laft mo¬
ments 5 and thofe efpecially of high rank, from their
manners and fentiments, are expefted to meet death
with magnanimity : but an American favage in the mo¬
ment of punilhment appears to be more than human ; he
is a hero of the firft order, who braves his tormentors,
who provokes them to employ all their art, and who
confiders as his chief glory to bear the greateft degree
of pain without flirinking (fee America, N° 14, 27,
28, 29.). I he recital ot their tortures would appear
exaggerated, if it were not attefted by the belt autho-
rity, and if the favage nations among whom thofe cu-
ftoms are eftablilhed were not fufficiently known ; but
the excefs of the cruelty is not fo aftonilhing as the cou¬
rage of the viftim. The European expofed to fufferings
of the fame dreadful nature would rend heaven and earth
wuth his piercing cries and horrible groans j the reward
of martyrdom, the profpeft of eternal life, could alone
give him fortitude to endure fuch torments; but the fa¬
vage is not animated with this exalted hope. What fup-
ports him then in feenes of fo exquifite fuffering ? The
feeling of ftiame, the fear of bringing reproach on his
tribe, and giving a ffain to his fellows never to be wiped
away, are the only fentiments which influence the mind
of a favage, and which always prefent to his imagina¬
tion, animate him, fupport him, and lend him fpirit and
refolution. At the fame time, however powerful thofe
motives may be, they would not be alone fufficient, if
. 4 N 2 the
[ 651 j
(A) There are inltances of perfons who have died at the ooife of thunder without beiiw tout-hed A „„„
%hte„ed with the fall of a galley in which he happened to be. was immediately fktd wl.K black iafndTce
M- te C:" motions a young perfon on whom the infolence of another made fuch an in,predion that his con n
pearnd Vel kT’ i“d then changed into black in fuch a manner that in T^’eigt days hTap:
bad hlbh * of black velvet : he continued in this date for four months, without any other fymntom of
and epilepfy. 6 ' ' J accordmg to many phyficians, produces madnefe
P L E [ 65:
Pleafure. the favage felt pain in the fame degree with the Euro-
—-'v-—pcan. benlibility, as we have already obierved, is in-
created by education j it is influenced by fociety, man¬
ners, laws, and government j climate and lood work it
into a hundred diilerent fivapes ; and all the phyfical and
moral caufes contribute to increafe and diminiili it. The
habitual exiftence of a favage would be a ftate of fuller¬
ing to an inhabitant of Europe. You muft cut the tieth
of the one and tear it away with your nails, before you
can make him feel in an equal degree to a fcratch or
prick of a needle in the other. The favage, doubtlefs,
fuffers under torture, but he iuflers much lels than an
European in the fame circumifances : the reafon is ob¬
vious ; the air which the favages breathe is loaded with
fog and moiil: vapours; their rivers not being confined
by high banks, are by the winds as well as in floods
fpread over the level fields, and depofit on them a putrid
and pernicious flime ; the trees Iqueezed one upon an¬
other, in that rude and uncultivated country ferve ra¬
ther as a covering to the earth than an ornament. ln-
flead of thofe freth and delicious ihades, thole openings
in the woods, and walks crofting each other in all direc¬
tions, which delight the traveller in the fine lorelts of
France and Germany ; thofe in America ferve only, to
intercept the rays of the fun, and to prevent the benign
influence of his beams. 1 he favage participates of tins
cold humidity *, his blood has little heat, his humours
are grofs, and his conftitution phlegmatic. lo the
powerful influence of climate, it is neceflary to join the
habits of his life. Obliged to traverfe vaft deferts for
fubfiftence, his body is accuftomed fatigue 5 food not
nourifhing, and at the fame time in no great plenty,
blunts his feelings 5 and all the hardlhips of the favage
ftaie give a rigidity to his members which makes him
almoft incapable of fuffering. The favage in this Hate
of nature may be compared to our water-women and
ftreet-porters, who, though they poffefs neither great
vigour nor ftrength, are capable of performing daily,
and without complaint, that kind of labour which to a
man in a different condition of life would be a painful
and grievous burden. Feeling, in lefs perfection with
the favage, by the effeCts of climate and food, and the
habits of his life, is (till farther reflrained by moral con-
ftderations. The European is lefs a man of nature than
of fociety : moral reftraints are powerful with him;
while over the American they have fcarcely any in¬
fluence. This latter then is in a double condition of
imperfeftion with regard to us j his fenfes are blunted,
and his moral powTers are not difclofed. Now, pleafure
and pain depending on the perfection of the fenfes and
the unfolding of the intellectual faculties, it cannot be
doubted, that in enjoyments of any kind favage.s expe¬
rience lefs pleafure, and in their fuffering lefs pain, than
Europeans in the fame circumftances. And in faCt,.the
favages of America poffefs a very feeble conftitution.
They are agile without being ftrong •, and this agility
depends more on their habits than on the perfection of
their members : they owe it to the neceflity ol hunting ;
and they are moreover fo -weak, that they were unable
to bear the toil which their fir ft oppreffors impofed on
them. Hence a race of men in all refpeCts fo imperfeCt
could not endure torment under which the moft robuft
European would fink, if the pain which they feel were
really as great as it appears to be. Feeling is then, and
]
P L E
muft neceffarily be, lefs in the favage condition ; for Plenfurc.
this faculty diiclofing itfelf by the exercife of all the ' v-—--'
phyfical and moral qualities, muft be lefs as they are lefs
exercifed. Every thing (hows the imperfeCtion of this
precious quality, this lource of all our affeCtions, in the
American lavages.
“ All the improvements in Europe have had a ten¬
dency to unfold fenflbility : the air is purified that we
may breathe more freely; the moraffes are drained, the
rivers are regulated in their courfes, the food is nouriih-
ing, and the houfes commodious. With the favages, on
the contrary, every thing tends to curb it; they take
pleafure even in hardening the organs of the body, in
accufloming themfelves to bear by degrees the moft
acute pain without complaining. Toys and girls among
the favages amufe themfelves with tying their naked
arms together, and laying a kindled coal between them,
to try which of them can longeft iufibr the heat ; and
the warriors who alpire to the honour of being chief,
undergo a courfe of fuffering which exceeds the idea
of torture infiiCfed on the greateft criminals in Eu¬
rope.”
Thefe obfervations on the pleafures and pains of fava¬
ges appear to be well-founded, and, as the attentive
reader will perceive, are perfectly agreeable to the the¬
ory of Dr Sayers. If indeed that theory be juft, as we
believe it to be, it will follow, that the few pleafures of
fenfe which the American enjoys, he ought to enjoy
more completely than any European, becaufe to him
they recur but feldom. This may very pofiibly be the
cafe ; and certainly would be fo, were not his fibres, by
climate and the habits of his life, rendered more rigid
than thofe of the civilized part of the inhabitants of Eu¬
rope. But if we agree with our author * in what he * Encyclo-
fays of the pains and pleafures of favages, we cannot zd-fcdie Me-
mit, without many exceptions, his theory of the enjoy-
ments of children. It is fo far from being true, that
fewT things amufe, and that nothing latisfies them, thatfqye, et
the direft contrary muft have been obferved by every Morale,
man attentive td the operations of the infant mind,tom-iV-
which is amufed with every thing new, and often com¬
pletely fatisfied with the mereit trifle. The pleafures
of philofophy are not indeed unfolded to the infant ;
but it by no means follows that he does not enjoy his
rattle and his drum as much as the philofopher enjoys
his telefcope and air-pump ; and if there be any truth in
the fcience of phyfiognomy, the happinefs of the former
is much more pure and exquifite than that of the latter.
That the moll perfeft mufic is vain noiie to an infant, is
far from being felf-evident, unlefs the author confines
the ftate of infancy to a very few months ; and we are
not difpofed to believe, without better proof than we
have yet received, that the relifh of exquifite perfumes
and highly-feafoned difhes adds much to the fum of hu¬
man felicity.
But however much we difapprove of many of thefe
reflections, the followfing w7e cordially adopt as our own.
“ If we compare (fays our author) the pleafures of
fenfe with thofe which are purely intelleftual, we {hall
find that the latter are infinitely fuperior to the former,
as they may be enjoyed at all times and in every fit na¬
tion of life." What are the pleafures of the table, fays
Cicero, of gaming, and of women, compared with the
delights of iludy ? This tafte increafes with age, and no
happinefs
P L E
F’?«fure. kappinefs is equal to it. Without knowledge and fludy,
v fays Cato, life is almoft the image of death (s). 'L'he
pleafures of the foul are fuch, that it is frequent enough
to fee men preferve their gaiety during their whole life,
notwithhanding a weak, difeafed, and debilitated body.
Scaron, who lived in the laid century, wjas an ex¬
ample of this. - Balzac, fpeaking of him, fays, that Pro-
metheus, Hercules, and Philocfetes, in profane, and
Job in facred, hiftory, faid many great things while they
were afflicted with violent pain 5 but Scaron alone
laid pleafant things. I have feen, continues be, in ma¬
ny places of ancient hiftory, conftancy, and modefty,
and wifdom, and eloquence, accompanying affliction ;
but lie is the only inftance wherein I have feen plea-
fan try.
“ There are men whofe underftandings are conftantly
on the ftretch, and by this very means they are impro¬
ved ; but if the body were as conftantly employed in
the purfuit of fenlual gratification, the conftitution
would foon be deitroyed. 'The more we employ the
mind we are capable of the greater exertion ■, but the
more we employ the body we require the greater re-
pofe. There are befides but fome parts of the body
capable of enjoying pleafure ; every part of it can expe¬
rience pain. A toothach occafions more fuffering than
the molt confiderable of our pleafures can procure of en¬
joyment. Great pain may continue for any length of
time ; exceffive pleafures are almoft momentary. Plea-
fare carried to an extreme becomes painful ; but pain,
either by augmenting or diminiftiing it, never becomes
agreeable. For the moment, the pleafures of the fenfes
are perhaps more fatisfaftory ; but in point of duration
thofe of the heart and mind are infinitely preferable.
All the fentiments of tendernefs, of friendfhip, of gra¬
titude, and of generofity, are iburces of enjoyment for
man in a ftaie of civilization, The damned are exceed-
ingly unhappy, faid St Catherine de Sienna, if they are
incapable of loving or being beloved.
“ Pleafure, continued for a great length of time, pro¬
duces languor and fatigue, and excites deep 5 the con¬
tinuation of pain is produflive of none of thefe effedfts.
Many fuffer pain for eight days and even a month with¬
out interruption ; an equal duration of exceflive pleafure
’would occafion death.
“ Time is a mere relative idea with regard to pleafure
and pain ; it. appears long when we fuffer, and ftiort
■when we enjoy. If there exifted no regular and uniform
movement in nature, we would not be able from our
fenfations alone to meafure time with any degree of ex-
ablnefs, for pain lengthens and pleafure abridges it.
From the languor of unoccupied time has arifen the pro¬
verb expreffive of our defire to ki// it. It is a melan¬
choly reflexion, and at the fame time true, that there
is no enjoyment which can effeclually fecure us from
pain tor the remainder of our lives ; while there are ex¬
amples of evils which hold men in conftant forrow and
P L E
pain during their whole exiftence. Such then is the Pleafum.
imperfe&ion of the one and the power of the other. v
“ Pleafure and pain are the Iburces of morality 5 an
aftion is juft or unjuft, good or otherwife, only as its
natural tendency is to produce fuffering or enjoyment
to mankind. No crime could be committed againft a
being altogether infenftble, nor could any good be be¬
llowed on it. Unlefs he were endowed with the defire
of pleafure and the apprehenfion of pain, man, like an
automaton, would a6t from neceffity, without choice and
without determination.
“ All our paffions are the developemer.t of fenfibility.
If we were not poffeffed of feeling, we fbould be deiii-
tute of paffions } and as fenfibility is augmented by ci¬
vilization, the paffions are multiplied ; more active and
vigorous in an extenfive and civilized empire than in a
fmall Hate ^ more in the latter than among barbarous
nations 5 and more in thefe laff than among lavages (Tea
Passion). There are more paffions in France and
England than in all the nations of Europe ; becaufe
every thing which ferves to excite and fofter them is al¬
ways in thofe countries in the greateft ftate of fermenta¬
tion. 1 he mind is active j the ideas great, extenfive,
and multiplied. And is it not the foul, the mind, and
heart, which are the focus of all the paffions ?”
But wherever the paffions are multiplied, the fources
of plealiire and pain are multiplied with them. This
being the cafe, it is impoffible to prefcribe a fixed and
general rule of happinefs fuited to every individual.
There are objedfs of pleafure with regard to which all
men of a certain education are agreed ; but there are
perhaps many more, owing to the variety of tempers-
and education, about which they differ. Every man
forms ideas of enjoyment relative to his character j and
what pleafes one may be utterly detefted by another.
In proportion as a nation is civilized and extenfive, thofe
differences are remarkable. Savages, who are not ac¬
quainted with all the variety of European pleafures,
amufe themfelves with very few objefts. Owing to the
want of civilization, they have fcarcely any choice in
the objects of tafte. They have few paflions; we have
many. But even in the nations of Europe pleafure is
infinitely varied in its modification and forms. Thofe
differences arife from manners, from governments, from
political and religious cuftoms, and chiefly from educa¬
tion. Meanwhile, however different and variable the
ideas of pleafure may be among nations and individuals,
it ftill remains a faff, that a certain number of perfons
in all civilized ftates, whether diftinguifhed by birth, or
rank, or fortune, or talents, as they have nearly the.
fame education fo they form nearly the fame ideas of
happinefs : but to poffefs it a man muff give his chief ap¬
plication to the ftate of his mind ; and notwithftanding
all his efforts it is of uncertain duration. Happinefs is
the fun (bine of life : we enjoy it frequently at great in¬
tervals ; and it is therefore necefiary to know how to
ufe
[ 653 1
(b) “ Savages, barbarians, and peafants, enjoy little happinefs except that of fenfation, The happinefs of a ci¬
vilized and well-informed man confifts of fenfations, of ideas, and of a great number ©f affinities, altogether unknown
to them. He not only enjoys the prefent, but the part and the future. He recals the agreeable idea of pleafures
wnich he has tafted. It is great happinefi;, fays an ancient, to have the recolledlion of good actions, of an upright
intention, and of promifes which we have kept.”
P L E [ 6-
Pleafure ufe it. All tlie produftions of art periili tKe largefl
11 fortunes are diffipated : rank, honour, and dignity pafs
't:‘ '' ‘ . away like a fleeting fliadow 5 the memory is impaired ;
all the faculties of the foul are extinguilhed ; the body
links under the infirmities of old age } and fcarcely has
one reached the boundaries of happinefs marked out by
his imagination, when he mull giv^ place to anothei,
and renounce all his pleafures, all his hopes, all his illu-
fions ; the fugitive images of which had given happinefs
,to the mind.
There are pleafures, however, on which the mind may
fecurely reft, which elevate man above himfelf, dignify
his nature, fix his attention on fpiritual things, and ren¬
der him worthy of the care of Providence. Thefe are
to be found in true religion 5 which procures for thofe
who pra£Hfe its duties inexpreflible happinefs in a better
country, and is in this world the fupport of the weak,
and the fweet confolation of the unfortunate.
PLEBEIAN, any perfon of the rank of the com¬
mon people. It is chiefly ufed in fpeaking of the an¬
cient Romans, who were divided into fenators, patrici¬
ans, and plebeians. The diftinffion was made by Ro¬
mulus the founder of the city ", who confined all digni¬
ties, civil, military, and facerdotal, to the rank of pa¬
tricians. But to prevent the feditions which fuch a di-
llinftion might produce through the pride of the higher
order and the envy of the lower, he endeavoured to_en¬
gage them to one another by reciprocal ties and obliga¬
tions. Every plebeian was allowed to choofe, out of
the body of the patricians, a prote&or, who fhould be
obliged to aflift him with his intereft and fubftance, and
to defend him from oppreftion. Thefe proteftors were
called patrons ; the protected, clients. It was the duty
of the patron to draw up the contrails of tire clients,, to
extricate them out of their difficulties and perplexities,
and to guard their ignorance againft the artfulnefs of the
crafty. On the other hand, if the patron was poor, his
clients were obliged to contribute to the portions of his
daughters, the payment of his debts, and the ranfom of
him and his children if they happened to be taken in
war. The client and patron could neither accufe nor
bear vvitnefs againft each other } and if either of them
was convifted of having violated this law, the crime
was equal to that of treafon, and any one might with
impunitv flay the offender as a vidlim devoted to Pluto
and the infernal gods. ¥or more than 600 years we
find no diffenfions or jealoufies between the patrons and
their clients ; not even in the times of the republic,
when the people frequently mutinied againft the great
and powerful.
PLECTRANTHUS, a genus of plants belonging
to the didynamia clafs } and in the natural method
ranking under the 4 2d order, Verticillatce. See Botany
Index.
PLEDGE (Plegius), in common law, a furety or
gage, either real or perfonal, which the plaintiff or de¬
mandant is to find for his profecuting the fuit.
The word is fometimes alfo ufed for FbANK Fledge,
which fee.
To PLEDGE, in drinking, denotes to warrant, or be
furety to one, that he (hall receive no harm while he is
taking his draught. The phrafe is referred by antiqua¬
ries to the pradrice of the Danes heretcffire in Eng¬
land, who frequently ufed to ftab or cut the throats of
the natives while they were drinking.
4
4 ] P L E
PLEDGES of Goods for money. See Pawn. PisJgei
PLEDGERY, or Pleggery, in Law, furetilhip, pi^ll^
or an undertaking or anfwering for another. , ' - A
PLEDGET, Bolster, or Cotnprefs, in Surgery, a
kind of flat tent laid over a wound, to imbibe the fuper-
fluous humours, and to keep it clean.
PLEIADES, in fabulous hiftory, the feven daugh¬
ters of Atlas king of Mauritania and Pleione, were thus
called from their mother. They w’ere Mala, Eledtra,
Taygete, Afterope, Merope, Halcyone, and Celceno;
and were alfo called Atlantides, from their father Atlas.
Thefe princeffes were carried off by Bufiris king cf
Egypt 5 but Hercules having conquered him, delivered
them to their father : yet they afterwards fuffered a new
perfecution from Orion, who purfued them five years,
till .love, being prevailed on by their prayers, took them
up into the heavens, where they form the conftellation
which bears their name.
Pleiades, in AJlronotny, an affemblage of feven ftars,
in the neck of the conftellation Taurus.
They are thus called from the Greek crAto, navigare,
“ to fail as being terrible to mariners, by reafon of
the rains and ftorms that frequently rife with them.
The Latins called them vergilhe, from ver, “ fpring j”
becaufe of their rifing about the time of the vernal equi¬
nox. The largeft is of the third magnitude, and is cal¬
led lucida pleiadum.
PLENARY, fomething complete or full. Thus we
fay the pope grants plenary indulgences} i. e. full and
entire remiffions of the penalties due to all fins. See In¬
dulgences.
PLENIPOTENTIARY, a perfon veiled with full
power to do any thing. See Ambassador.
PLENITUDE, the quality of a thing that is full,
or that fills another. In medicine, it chiefly denotes a
redundancy of blood and humours.
PLENUM, in Physics, denotes, according to the
Cartefians, that ftate of things wherein every part of
fpace is fuppofed to be full of matter, in oppofition to
a Vacuum, which is a fpace fuppofed devoid of all
matter.
PLENUS FLOS, a full flower •, a term exprefllve of
the higheft degree of luxuriance in flowers. See Bo¬
tany. Such flowers, although the moft delightful to
the eye, are both vegetable monfters, and, according
to the fexualifts, vegetable eunuchs; the unnatural in-
creafe of the petals conftituting the firft •, the confequent
exclufion of the ftamina or male organs, the latter.
The following are well-known examples of flowers
with more petals than one •, ranunculus, anemone, tnarfti-
marygold, columbine, fennel-flower, poppy, pteony,
pink, gilliflower, campion, vifcous campion, lily, crown
imperial, tulip, narciffus, rocket, mallow, Syrian mal¬
low, apple, pear, peach, cherry, almond, myrtle, rofe,
and ftrawberry.
Flowers with one petal are not fo fubjeft to fullnefs.
The following, however, are inftances : polyanthus, hy¬
acinth, primrofe, crocus, meadow-faffron, and thorn-
apple •, though Kramer has afferted that a full flower
with one petal is a contradifrion in terms. In flowers
with one petal, the mode of luxuriance, or impletion,
is by a multiplication of the divifions of the limb or up¬
per "part; in flowers with more petals than one, by a
multiplication of the petals or neftarium.
To take a few examples. Columbine is rendered full
in
l
P L E [ C
Plenum in three different ways: I. By the multiplication of its
‘—  ' petals, and total exclufion of the neftaria j 2. By the
multiplication of the ne&aria, and exclufion of the pe¬
tals ; or, 3. By fuch an increafe of the neclaria only as
does not exclude the petals, between each of which are
interjected three nedtaria, placed one within another.
Again, fennel-flower is rendered full by an increafe of
the nedtaria only j narciflus, either by a multiplication
of its cup and petals, or of its cup only $ larkfpur com¬
monly by an increafe of the petals and exclufion of the
fpur, which is its nedtarium. In faponaria concava an-
g/ia, the impletion is attended with the Angular effedt
of incorporating the petals, and reducing their number
from five to one; and in gelder-rofe, the luxuriance is
effedted by an increafe both in magnitude and number
of the circumference or margin of the head of flowers,
in the plain, wheel-fhaped, barren florets j and an exclu¬
fion of all the bell-fhaped hermaphrodite florets of the
centre or dilk.
Hitherto we have treated of plenitude in Ample flow¬
ers only : the inftance juft now adduced feems to connedl
the different modes of impletion in them and compound
flowers. Before proceeding farther, however, it will
not be improper to premife, that as a Ample luxuriant
flower is frequently, by beginners, miftaken for a com¬
pound flower in a natural ftate, fuch flowers may always
be diftinguiftied with certainty by this rule : That in Am¬
ple flowers, however luxuriant, there is but one piftillum
or female organ ; whereas in compound flowers, each
floret, or partial flower, is furnilhed with its own proper
piftillum. Thus in hawk-weed, a compound flower,
each flat or tongue-ftiaped floret in the aggregate has its
five ftamina and naked feed, which laft is in effedl its
piftillum ; whereas, in a luxuriant lychnis, which is a
Ample flower, there is found only one piftillum or female
organ common to the whole.
In a compound radiated flower, which generally con-
fifts of plain florets in the margin or radius, and tubular
or hollow florets in the centre or dife, plenitude is ef-
fedled either by an increafe of the florets in the margin,
and a total exclufion of thofe in the dife •, which mode of
luxuriance is termed impletion by the radius, and refem-
bles what happens in the gelder-rofe : or by an elonga¬
tion of the hollow florets in the centre, and a lefs pro¬
found divifion of their brims ; which is termed impletion
by the dife. In the firft mode of luxuriance, the florets
in the centre, which are always hermaphrodite or male,
are entirely excluded; and in their place fucceed florets
fimilar in fex to thofe of the radius. Now as the florets
in the margin of a radiated compound flower are found
to be always either female, that is, furniihed with the
piftillum only 5 or neuter, that is, furniftied with neither
ftamina nor piftillum j it is evident, that a radiated com¬
pound flower, filled by the radius, will either be entire¬
ly female, as in feverfew, daify, and African marigold j
or entirely neuter, as in fun-flower, marygold, and cen¬
taury : hence it will always be eafy to diftinguilh fuch a
luxuriant flower from a compound flower with plain flo¬
rets in a natural ftate; as thefe flowers are all herma¬
phrodite, that is, furniihed with both ftamina and piftil¬
lum. Thus the full flowers of African marigold have
each floret furniihed with the piftillum or female organ
only : the natural flowers of dandelion, which, like the
former, is compofed of plain florets, are furniihed with
both ftamina and piftfllum.
'55 1 P L E
In the fecond mode of luxuriance, termed impletion by P’ciius
the dife, the florets in the margin fometimes remain un- 1| ^
changed : but moil commonly adopt the figure of thofe , J£ ',0!aJ
in the centre, without, however, fuffering any alteration
in point of fex ; fo that confufion is lefs to be apprehend¬
ed from this mode of luxuriance than from the former
befides, the length to which the florets in the centre run
out is of itfelf a fuificient diftinction, and adapted to ex¬
cite at once an idea of luxuriance. Daify, feverfew, and
African marigold, exhibit inftances of this as well as of
the former mode of impletion.
In luxuriant compound flowers with plain florets, the
femiflofeulof of Tournefort, the ftigma or fummit of the
ftyle in each floret is lengthened, and the feed-buds are
enlarged and diverge j by which characters fuch flowers
may always be diftinguithed from flowers of the fame
kind in a natural ftate. Scorzonera, nipple-wort, and
goat’s-beard, furnifli frequent inftances of the plenitude
alluded to.
Laftly, the impletion of compound florvers with tu¬
bular or hollow florets, the fofeulof of Tournefort, feems
to obferve the fame rules as that of radiated flowers juft
delivered. In everlafting-flower, the xeranthemum of
Linnaeus, the impletion is Angular, being effe&ed by ther
enlargement and expanfion of the inward chaffy feales of
the calyx. Thefe feales, which become coloured, are
greatly augmented in length, fo as to overtop the florets,
which are fcarce larger than thofe of the fame flower in
a natural ftate. The florets too in the margin, which
in the natural flower are female, become, by luxuriance,
barren ; that is, are deprived of the piftillum $ the ftyle,
which was very fhort, fpreads, and is of the length of
the chaffy feales $ and its fummits, formerly two in num¬
ber, are metamorphofed into one.
Full flowers are more eafily referred to their refpe&ive
genera in methods founded upon the calyx, as the flower-
cup generally remains unaffected by this higheft degree
of luxuriance.
PLEONASM, a figure in Rhetoric, whereby we ufe
W’ords feemingly fuperfluous, in order to exprefs a thought
with the greater energy; fuch as, “ I faw it writh my
own eyes,” &c. See Oratory, N° 67.
PLESCOW, a towm of Ruflia, capital of a duchy of
the fame name, with an archbiftiop’s fee, and a ftrong
caftle. It is a large place, and divided into four parts, -
each of which is furrounded with walls. It is feated on
the river Muldow, where it falls into the lake Plefcow.
80 miles fouth of Narva, and 150 fouth by weft of Pe^-
terfburg. E. Long. 27. 52. N. Lat. 57. 58.
Pi.escow, a duchy in Ruflia, between the duchies of
Novogorod, Lithuania, Livonia, and Ingria.
PLESSIS-les-tours, formerly a royal p'alace of
France, within half a league of Tours. It wras built by
Louis XL and in it he died in the year 1483. It is fi-
tuated in a plain furrounded by woods, at a fmall dif-
tance from the Loire. The building is yet handfome,,
though built of brick, and converted to purpofes of com¬
merce.
PLETHORA, in Medicine, from 7rA>!0«s, “ pleni¬
tude.” A plethora is when the veffels are too much
loaded wuth fluids. The plethora may be fanguine or fe-
rous. In the firft there is too much craffamentum in the-
blood, in the latter too little. In the fanguine plethora,
there is danger of a fever, inflammation, apoplexy, rup¬
ture of the blood-veffelsj obftruCted fecretions, &c. : in
thte"
P L E [ 656 ] P L I
Plethora the ferou’S, of a dropfy, &c. A rarefaction of the blood
flours produces all the effe&s of a plethora ) it may accompany
LU ' , a plethora, and fltould be diftinguifhed therefrom. Mr
Bromfield obferves, that a fanguine plethora may thus
be known to be prefent by the pulfe. An artery over¬
charged with blood is as incapable of producing a ftrong
full pulfe, as one that contains a deficient quantity *, in
both cafes there will be a low and weak pulfe. To dif-
tinguilh rightly, the pulfe muft not be felt with one or
two fingers on the carpal artery 5 but if three or four
fingers cover a confiderable length of the artery, and we
prefs hard for fome time on it, and then fuddenly raife
all thefe fingers except that which is neareit to the pa¬
tient’s hand, the influx of the blood, if there is a pletho¬
ra, will be fo rapid as to raife the other finger, and
make us fenfible of the fulnefs. The fanguine plethora
is relieved by bleeding : the ferous by purging, diuretics,
and fweating. See Medicine Index.
PLEURA, in Anatomy, a thin membrane covering
the infide of the thorax. See Anatomy Index.
PLEURITIS, or Pleurisy. See Medicine In¬
dex.
PLEURONECTES, a genus of fifties belonging to
the order of thoracici. See Ichthyology Index.
PLEURS, a town in France, which was buried un¬
der a mountain in the year 1618. Of this fatal circum-
ilance, Bifliop Burnet, in his Travels, p. 96. gives the
following account. “ Having mentioned (fays the Bi-
Ihop) fome falls of mountains in thefe parts (viz. near
the Alps), I cannot pafs by the extraordinary fate of the
town of Pleurs, about a league from Chavennes to the
north.—The town was half the bignefs of Chavennes, but
much more'nobly built •, for, befides the great palace of
the Francken, that coft fome millions, there were many
other palaces built by rich faflors both of Milan and the
other parts of Italy, who, liking the fituation and air,
as well as the freedom of the government, gave them-
felves all the indulgences that a vaft wealth could fur-
nifli. By one of the palaces that was a little diftant
from the town, and was not overwhelmed with it, one
may judge of the reft. It was an out-houfe of the fami¬
ly of the Francken, and yet it may compare with many
palaces in Italy. The voluptuoufnefs of this place be¬
came very crying *, and Madame de Sails told me that
the heard her mother often relate fome paflages of a Pro-
teftant minifter’s fermons that preached in a little church
there, who warned them often of the terrible judgements
of God which were hanging over their heads, and which
he believed would fuddenly break out upon them.
“ On the 25th of Auguft 1618, an inhabitant came
and told me to be gone, for he faw the mountains cleav¬
ing j but he was laughed at for his pains. He had a
daughter whom he perfuaded to leave all and go with
him •, but when fhe was fafe out of town, (he called to
mind that (lie had not locked the door of a room in which
Ihe had fome things of value, and fo ftie went back to do
that, and was buried with the reft •, for at the hour of
fupper the hill fell down, and buried the town and all
the inhabitants, to the number of 220c, fo that not one
perfon efcaped. The fall of the mountains did fo fill the
channel of the river, that the firft news thofe of Chaven¬
nes had of it was by the failing of their river } for three
or four hours there came not a drop of water, but the
river wrought for itfelf a new courfe, and returned to
them.
£
“ I could hear no particular charafter of the man who Plears
efcaped (continues the Bifliop) ; fo I muft leave the ie- I!
cret reafon of fo Angular a prefervation to the great dif- Eunpton..
covery, at the laft day, of thofe fteps of-Divine Provi- "v~'
deuce that are now fo unaccountable. Some of the fa¬
mily of the Francken got fome miners to work under
ground, to find out the wealth that was buried in their
houfe $ for, befides their plate and furniture, there was
a great deal of ca(h and many jewels in the houfe. The
miners pretended they could find nothing.; but they
went to their country of Tyrol and built fine houfes, and
a great wealth appeared, of which no other vifible account
could be given but this, that they had found fome of that
treafure.”
PLEXUS, among anatomifts, a bundle of fmall yef-
fels interwoven in the form of net work 5 thus a conge¬
ries of veflels within the brain is called plexus choraides,
reticularis, or retiformis. See Anatomy.
A plexus of nerves is the union of two or more nerves,
forming a fort'of ganglion or knot. <*
PLICA polonica, or plaited hair, is a difeafe pecu¬
liar to Poland $ whence the name. See Medicine, N°
355. Mr Coxe, who gives a ftiort account of it, attempts
likewife to give the phyfical caufes of it. Many caufes
of this kind, he tells us, have been fuppofed to concur
in rendering the plica more frequent in thofe regions than
in other parts. It would be an endlefs work to enumer¬
ate the various conjeftures with which each perfon has
fupported his favourite hypothefis.—The moft probable
are thofe aftigned by Dr Vicat : The firft caufe is the
nature of the Polifti air, which is rendered ittfalubrious
by numerous Woods and morafies, and occafionally de¬
rives an uncommon keennefs even in the midft of fum-
mer from the pofition of the Carpathian mountains; for
the fouthern and fouth-eafterly winds, which ufually con¬
vey warmth in other regions, are in this chilled in their
paffage over their fnowy fummits. The fecond is, un-
wholefome water ; for although Poland is not deficient
in good fprings, yet the common people ufually drink
that which is neareft at hand, taken indifcriminately
from rivers, lakes, and even ftagnant pools. The third
caufe is the grofs inattention of the natives to cleanlinefs;
for experience ftrows, that thofe who are not negligent
in their perfons and habitations, are lefs liable to be af-
flifted with the plica than others who are deficient in
that particular. Thus perfons of higher rank are lefs fub-
jeft to this diforder than thofe of inferior itations; the
inhabitants of large towns than thofe of fmall villages j
the free peafants than thofe in an abfolute ftate of vaflal-
age *, the natives of Poland Proper than thofe of Lithu¬
ania. Whatever we may determine as to the poflibility
that all or any of thefe caufes, by themfelves, or in con-
junclion with others, originally produced the diforder;
we may venture to affert, that they all, and particular¬
ly the laft, aflift its propagation, inflame its fymptoms,
and protradl its cure.
In a word, the plica polonica appears to be a conta¬
gious diftemper \ which, like the leprofy, ftill prevails
among a people ignorant in medicine, and inattentive to
check its progrefs, but is rarely known in thofe corii-
tries where proper precautions are taken to prevent its
fpreading.
PLIMPTON, a town of Devonfture, in England,
feated on a branch of the river Plime, which had once
a caftle, now in ruins. It fends two members to parli-
ment,j
P L I
r e
Piiny.
Plinia mentj is feven miles E. of Plymouth, and 218 W. by
S. of London. W. Long. 40. o. N. Lat. 50. 22.
^ PL INI A, a genus of plants belonging to the polyan-
dria clafs of Linnaeus. See Botany Index.
PLINTH, Orle, or Orlo, in Architecture, a flat
fquare member, in the form of a brick.- It is ufed as
the foundation of columns, being that flat fquare table
under the moulding of the bafe and pedeftal at the bot¬
tom of the whole order. It feems to have been origi¬
nally intended to keep the bottom of the original wood¬
en pillars from rotting. Vitruvius alfo calls the Tuf-
can abacus plinth.
PLINTH of a Statue, See. is a bafe, either flat, round,
or fquare, that ferves to fupport it.
PLINTH of a Wall, denotes two or three rows of
bricks advancing out from a wall} or, in general, any
flat high moulding, that ferves in a front-wall to mark
the floors, to fuflain the eaves of a wall, or the larmier
of a chimney.
PLINY the Elder, or Ccccilius Plinius Secundus,
one of the mofl learned men of ancient Rome, was de-
feended from an illuftrious family, and born at Verona.
He bore arms in a diftinguifhed poll 5 was one of the
college of augurs 5 became intend ant of Spain j and
was employed in feveral important affairs by Vefpafian
and Titus, who honoured him with their efteem. The
eruption of Mount Vefuvius, which happened in the
year 79, proved fatal to him. His nephew, Pliny the
Younger, relates the circumftances of that dreadful
eruption, and the death of his uncle, in a letter to Ta¬
citus. Pliny the Elder wrote a Natural Hiftory in 37
books, which is flill extant, and has had many editions j
the mofl efleemed of which is that of Father Hardouin,
printed at Paris in 1723, in two volumes folio.
PLINT the Younger, nephew of the former, was
born in the ninth year of Nero, and the 6 2d of Chrifl,
at Novocomum, a town upon the lake Larius, near
which he had feveral beautiful villas. Ccecilius was the
name of his father, and Plinius Secundus that of his
mother’s brother, who adopted him. He bi'ought into
the world with him fine parts and an elegant tafle,
which he did not fail to cultivate early j for, as he tells
us himfelf, he wrote a Greek tragedy at 14 years of
age He loft his father when he was young *, and had
the famous Virginius for his tutor or guardian, whom
he has fet in a glorious light. He frequented the fchools
of the rhetoricians, and heard Quintilian ; for whom
he ever after entertained fo high an efteem, that he be¬
llowed a confiderable portion upon his daughter at her
marriage. He was in his 18th year when his uncle died j
and it was then that he began to plead in the forum,
which was the ufual road to dignities. About a year af¬
ter, he aflumed the military charadler, and went into Sy¬
ria with the commiflion of tribune : but this did not fuit
his tafte any more than it had done Tully’s 5 and there¬
fore we find him returning after a campaign or two. He
tells us, that in his paflage homewards he was detained
by contrary winds at the ifland Icaria, and how he em¬
ployed himfelf in making verfes : he enlarges in the fame
place upon his poetical exercitations} yet poetry was
mot the fhining part of his character any more than it
had been of Tully’s.
Upon his return from Syria, he married a wife, and
fettled at Rome : it was in the reign of Domitian. Du¬
ring this moft perilous time, he continued to plead in
\ OL. XVI. Part II,
57 1 PL I
the forum, where he was not more diftinguifhed by his
uncommon abilities and eloquence, than by his great
refolution and courage, which enabled him to fpeak
boldly, when fcarcely one elfe durfl fpeak at all. On
thefe accounts he was often fingled out by the fenate
to defend the plundered provinces againft their oppref-
five governors, and to manage other caufes of a like
important and dangerous nature. One of thefe was for
the province of Baitica, in their profecution of Baebius
Mafia 5 in which he acquired fo general an applaufe,
that the emperor Nerva, then a private man, and in ba-
nifhment at Tarentum, wrote to him a letter, in which
he congratulated not only Pliny, but the age which had
produced an example fo much in the fpirit of the an¬
cients. Pliny relates this affair in a letter to Cornelius
Tacitus and he was fo pleafed with it himfelf, that he
could not help intreating this friend to record it in his
hiftory. He intreats him, however, with infinitely
more modefty than Tully had intreated Lucceius upon
the fame occafion : and though he might imitate Cicero
in the requeft, as he profeffes to have conftantly fet that
great man before him for a model, yet he took care
not to tranfgrefs the bounds of decency in his manner
of making it. He obtained the offices of queftor and
tribune, and luckily went unhurt through the reign of
Domitian : there is, however, reafon to fuppofe, if that
emperor had not died juft as he did, that Pliny would
have fhared the fate of many other great men 5 for he.
tells us himfelf, that his name w'as afterwards found in
Domitian’s tables, among the number of thofe wrho wTere
deftined to deflru6lion.
He loft his wife in the beginning of Nerva’s reign,
and foon after married his beloved Calphurnia, of whom
we read fo much in his Epiftles, He had not, however,
any children by any of his wives: and hence we find
him thanking Trajan for the jus trium liberorum, which
he afterwards obtained of that emperor for his friend
Suetonius Tranquillus. He hints alfo, in his letter of
thanks to Trajan, than he had been twice married in
the reign of Domitian. He was promoted to the con-
fulate by Trajan in the year 100, when he was 38 years
of age and in this office pronounced that famous pa¬
negyric, which has ever fince been admired, as well for
the copioufnefs of the topics as the elegance of addrefs.
Then he wTas ele£ted augur, and afterwards made pro-
conful of Bithynia ; whence he w rote to Trajan that
curious letter concerning the primitive Chriftians j
wrhich, with Trajan’s refeript, is happily extant among
his Epiftles. Pliny’s letter, as Mr Melmoth obferves in
a note upon the paflage, is efteemed as almoft the only
genuine monument of ecclefiaftical antiquity relating
to the times immediately fucceeding the apoftles, it be¬
ing written at moft not above 40 years after the death
of St Paul. It was preferved by the Chriftians them-
felves, as a clear and unfufpicious evidence of the puri¬
ty of their doctrines, and is frequently appealed to by
the early writers of the church againft the calumnies of
their adverfaries. It is not known what became of Pli¬
ny after his return from Bithynia 5 whether he lived at
Rome, or what time he fpent at his country houfes. An¬
tiquity is alfo ftlent as to the time of his death : but it is
conjectured that he died either a little before or foon af¬
ter that excellent prince, his admired Trajan} that is,
about the year of Chrift 116.
Pliny was one of the greateft wits, and one of the
4 O worthieft
Pliny,
P L O _ _ f 658 ^
worthieft men, among the ancients. He had fine parts,
which he cultivated to the utmoft; and he accomplifh-
ed himfelf with all the various kinds of knowledge
which could ferve to make him either ufelul or agree¬
able. He wrote and publifned a great number of
things ; but nothing has efcaped the wreck of time ex¬
cept the books of Letters, and the panegyric upon
Trajan. This has ever been confidered as a mailer-
piece : and if he has, as feme think, almoii exhaufted
all the ideas of perfection in a prince, and gone per¬
haps a little beyond the truth, yet it is allowed that
no panegyrift w'as ever poiteiled of a finer fubjeft, and
on which he might better indulge in all the flow of elo¬
quence, without incurring the fufpicion of flattery and
lies. His letters feem to have been intended for the
public ; and in them he may be confidered as writing
his own memoirs. Every epiftle is a kind of hiftorical
fketch, wherein we have a view7 of him in fome ftriking
attitude either of aftive or contemplative life. In
them are preferved anecdotes of many eminent perfons,
w'hofe works have come down to us, as Suetonius, Si-
lius Italicus, Martial, Tacitus, and Quintilian ; and of
curious things, which throw great light upon the hi-
ilory of thofe times. They are written with great po-
litenefs and fpirit 5 and if they abound too much in
turn and metaphor, wre mull impute it to that degene¬
racy of talle which was then accompanying the degene¬
rate manners of Rome. Pliny, howrever, feems to have
preferved himfelf in this latter refpedl from the gene¬
ral contagion: whatever the manners of the Romans
were, his were pure and incorrupt. His writings
breathe a fpirit of tranfeendent goodnefs and humanity :
his only imperfection is, he was too defirous that the
public and potlerity fhould know how humane and good
he wras. We have twTo elegant Rnglifh tranflations of
Ids Epifiles ; the one by Mr Melmoth, and the other
by Lord Orrery.
PLOCAM A , a genus of plants belonging to the pent-
andria clafs. See Botany Index,
PLOCE. See Oratory, p. 433.
PLOCKSKO, a town of Poland, and capital of a
palatinate of the fame name, w ith a caftle and a bid)op’s
fee. The churches are very magnificent •, and it is built
upon a hill, ^whence there is a fine profpeCl; every wray,
near the river Viilula. It is 25 miles fouth-ead; of U-
ladiflaw, and 65 woil of Warfaw* E. Long. 19. 29.
N. Lat. 52. 46.
Plocksko, a palatinate of Poland, bounded on the
north by Regal Pruflia, on the eaft by the palatinate of
Mazovia, on the fouth by the Viftula, and on the weft
by the palatinate of Inovladidaw. The capital town is
of the fame name.
PLOEN is a town of Germany in the circle of
Lower Saxony, and capital of Holftein. It Hands on
the banks of a lake of the fame name, and gave title to
a duke, till by the death of the laft duke Charles with¬
out male iiTue it efeheated to the king of Denmark in
1761. The ducal palace, rifing in the midft of the towm,
on an elevated fpot of gi-ound, and overlooking the lake,
is a very pifturefque objedl. The town Hands 22 miles
north-weft of Lubeck, and 10 fouth-eaft of Kiell. E.
Long. 10. 30. N. Lat. 54. 11.
PLOMO, in Metallurgy, is a name given by the
Spaniards, who have the care of the filver mines, to the
ftlver ore, when found adhering to the furface of ftones,
P L O
and when it incrufts their cracks and cavities like fmall Plcma
and loofe grains of gun-powder. Though thefe grains . f)
be fewr in number, and the reft of the Hone have no HI- , * ‘otinu*-
ver in it, yet they are always very happy when they find
it, as it is a certain token that there is a rich vein fome-
wThere in the neighbourhood. And if in digging for¬
wards they ftill meet with thefe grains, or the plomo in
greater quantity, it is a certain fign that they are getting
nearer and nearer the good vein.
PLOT, Dr Robert, a learned antiquarian and phi-
lofopher, w7as born at Sutton-barn, in the paiifti of Bor¬
den in Kent, in the year 1641, and ftudied in Magda-
len-hall, and afterwards in Univerfity-college, Oxford.
In 1682 he was elefted fecretary of the Royal Society,
and publithed the Philofophical I ranfaftions from N°
143 to N° 166 inclufive. The next year Elias Afhmole,
Elq, appointed him firft keeper of his mufeum, and about
the fame time the vice-chancellor nominated him firft pro-
feffor of chemiftry in the univerfity of Oxford. In 1687
he was made fecretary to the Earl Marftial, and the fol¬
lowing year received the title of Hijloriographer to King
James II. In 1690 he refigned his profefforfhip of
chemiftry, and likewife his place of keeper of the mu¬
feum, to which he prefented a very large collection of
natural curiofities \ which were thofe he had deferibed
in his hiftories of Oxfordfhire and Staffordlhire : the
former publifned at Oxford in 1677, ar,d reprint¬
ed with additions and corrections in 1705 ; and the lat¬
ter was printed in the fame fize in 1686. In January
1694- Henry Howard, Earl Marfhal, nominated him
Mobray-herald extraordinary •, tw7o days after which he
was conftituted regifter of the court of honour 5 and,
on the 30th of April 1696, he died of the ftone at his
houfe in Borden.
As Dr Plot delighted in natural biftory, the above
works were defigned as eiTays towards a Natural Plifto-
ry of England \ and he had aClually formed a defign of
travelling through England and Wales for that purpofe.
He accordingly drew7 up a plan of his fcheme in a letter
to the learned Billiop Fell; which is inferted at the end
of the fecond volume of Leland’s Itinerary, of the edi¬
tion of 1744. Amongft feveral MSS. w7hich he left be¬
hind him were large materials for the “ Natural Hiftory
of Kent, Middlefex, and the city of London.” Befides
the above w7orks, he publiihed De origine fontium tenia-
men plulofophicum, 8vo, and nine papers in the Philofo¬
phical Tranfaclions.
Plot, in dramatic poetry, is fometimes ufed for the
fable of a tragedy or comedy j but more properly for the
knot or intrigue, which makes the embarras of any piece.
See Poetry.
Plot, in Surveying, the plan er draught of any field,
farm, or manor, iurveyed with an inftrument, and laid
down in the proper figure and dimenfions.
PLOTINUS, a Platonic philofopher in the third
century. He was born at Lycopolis, a city of Egypt,
in 204 •, and began very early to (how7 a great fingula-
rity both in his tafte and manners : for, at eight years
of age, when he went to fchool, he ufed to run to his
nurfe, and uncover her breaft to fuck ; and w7ould have
continued that praClice longer, if he had not been dif-
couraged by her. At 28 years of age he had a ftrong
defire to ftudy philofophy, on which occafion he was re¬
commended to the molt famous profeffors of Alexan¬
dria. He was not fatisfied with their leftures j but,
upon
P L O [ 65
Plotinu?. upon hearing thofe of Ammonius, he confeffed that this
^ was the man he wanted. He ftudied for 11 years un¬
der that excellent matter, and then went to hear the
Perfian and Indian philofophers: for in 243, when the
emperor Gordianus intended to wage war againft the
Perfians, he followed the Roman army, but probably
repented of it j for it was with difficulty he could fave
his life by flight, after the emperor had been flain. He
was then 3 9; and the year following he went to Rome,
and read philofophical le£tures in that city ; but avoid¬
ed following the example of Erennius and Origen, his
fellow-pupils, who, having promifed ■with him not to
reveal fome hidden and excellent doftrines they had re¬
ceived from Ammonius, had neverthelefs forfeited their
word. Plotinus continued ten years in Rome, without
writing any thing j but, in his 50th year, Porphyry be¬
came his fcholar who, being of an exquifitely fine ge¬
nius, was not fatisfied with fuperficial anfwers, but re¬
quired to have all difficulties thoroughly explained; and
therefore Plotinus, to treat things with greater accura¬
cy, was obliged to write more books. He had before
written 21 books, and during the fix years of Porphy¬
ry’s ftay with him he wrote 24, and 9 after Porphyry’s
leaving Rome, in all 54. The Romans had a high ve¬
neration for him; and he patted for a man of fuch judge¬
ment and virtue, that many perfons of both fexes, when
they found themfelves dying, intruded him, as a kind
of guardian angel, with the care of their eftates and
children. He was the arbiter of numberlefs law-fuits 5
and conftantly behaved with fuch humanity and recti¬
tude of mind, that he did not create himfelf one enemy
during the 26 years he refided in Rome. He, however,
did not meet with the fame juftice from all of his own
profeflion ; for Olympias a philofopher of Alexandria,
being envious of his glory, ufed his utmoft endeavours,
though in vain, to ruin him. The emperor Gallienus,
and the emprefs Salonina, had a very high regard for
him ; and, had it not been for the oppofition of fome
jealous courtiers, they would have had the city of Cam¬
pania rebuilt, and given to him with the territory be¬
longing to it, to eftabliffi a colony of philofophers, and
to have it governed by the ideal laws of Plato’s common¬
wealth. He laboured under various diforders during
the laft year of his life, which obliged him to leave
Rome, when he was carried to Campania to the heirs of
one of his friends, who furniffied him with every thing
neceflary; and he died there in the year 270, at the age
of 66, and in the nobleft manner that an heathen philo¬
fopher could do, thefe being his words as he breathed
his laft : “lam labouring with all my might to return
the divine part of me to the Divine Whole which fills
the univerfe.”
We have already remarked that the ideas of Plotinus
were fingular and extraordinary; and we (hall now ffiow
that they were fo. He was affiamed of bqing lodged in a
body, for which reafon he did not care to tell the place
of his birth or family. The contempt he had for all
earthly things, was the reafon why he would not permit
his pifture to be drawn : and when his difciple Amelius
was urgent with him upon this head, “ Is it not enough
(faid he) to drag after us, whitherfoever we go, that
image in which nature has ffiut us up ? Do you think
that we ffiould likewife tranfmit to future ages an image
of that image, as a fight worthy of their attentien ?”
From the fame principle, he refufed to attend to his
9 1
P L O
health •, for he never made ufe of prefervutives or baths, Plotinus,
and did not even eat the flefti of tame animals. He ate
but little, and abftained very often from bread 5 which,
joined to his intenfe meditation, kept him very much
from fleeping. In ftiort, he thought the body altogether
below his notice; and had fo little refpedt for it, that
he confidered it as a prifon, from which it would be his
fupreme happinefs to be freed. When Amelius, after
his death, inquired about the ftate of his foul of the
oracle of Apollo, he was told, “ that it was gone to the
aflembly of the blefled, where charity, joy, and a love of
the union with God prevail and the reafon given for
it, as related by Porphyry, is, “ that Plotinus had been
peaceable, gracious, and vigilant ; that he had perpetu¬
ally elevated his fpotlefs foul to God ; that he had loved
God with his whole heart; that he had difengaged him¬
felf, to the utmoft of his abilities, from this wretched
life ; that, elevating himfelf with all the powers of his
foul, and by the feveral gradations taught by Plato, to¬
wards that Supreme Being which fills the univerfe, he
had been enlightened by him; had enjoyed the vifion of
him without the help or interpofition of ideas j had, in
fhort, been often united to him.” This is the account
of Porphyry, who tells us alfo, that he himfelf had once
been favoured with the vifion. To this account, how¬
ever, -we need fcarcely add, that little credit is due : it
agrees pretty much with modern enthufiafm and the re¬
veries of Behmenifts. Plotinus had alfo his familiar
fpirit, as well as Socrates} but, according to Porphyry,
it was not one of thofe called demons, but of the order
of thofe who are called gods ; fo that he was under the
protection of a genius fuperior to that of other men.
The fuperiority of his genius puffed him up not a little :
for v7hen Amelius defired him to (hare in the facrifices,
which he ufed to offer up on folemn feftivals, “ It is
their bufinefs (replied Plotinus) to come to me, not
mine to go to them “ which lofty anfwer (fays Por¬
phyry) no one could guefs the reafon of, or dared to
afk.”
Porphyry put the 54 books of Plotinus in order,
and divided them into^ fix enneafes. The greater part
of them turn on the moft high-flown ideas in meta-
phyfics $ and this philofopher feems, in certain points,
not to differ much from Spinoza. He wrote two books
to prove, that “ all being is one and the fame }” which
is the very doClrine of Spinoza. He inquires, in ano¬
ther book, “ Whether there are many fouls, or only
one ?” His manner of compofing partook of the Angu¬
larity of his nature : he never read over his compofitiorfs
after he had written them ; he wrote a bad hand, and
was not exaCI in his orthography : he flood in need,
therefore, of a faithful friend to revife and correft his
writings: and he chofe Porphyry for this purpofe be¬
fore Amelius, who had, however, been his difciple 24
years, and was very much efteemed by him. Some have
accufed Plotinus of plagiarifm, with regard to Nume-
nius 5 a flander which Amelius refuted. Longinus was
once much prejudiced againft our great philofopher,
and w7rote againft his Treatife of Ideas, and againft
Porphyry’s anfwer in defence of that treatife. He af¬
terwards conceived a high efteem for him j fought in-
duftrioufly for all his books 5 and, in order to have them
very correCt, defired Porphyry to lend him his copy j
but at the fame time wrote to him in the following
manner : “ I always obferved to you, when we were to-
.4 O 2 gether,
P L U r 660 1 P L u
gether, wlaen \ve were at a diftance from one another,
as well as when you lived at Tyre, that I did not com¬
prehend many of the fubjedts treated of by Plotinus ;
but that 1 was extremely fond of his manner of writing,
the variety of his knowledge, and the order and difpo-
fition of his quelfions, which are altogether philofophi-
cal.” “ This tingle paffage (fays Bayle) {hows the
exalted genius, the exquifite difcernment, and judicious
penetration of Longinus. It cannot be denied, that
moll fubjects which this philofopher examines are in-
comprehentible ; neverthelefs, we difcover in his wrorks
a very elevated, fruitful, and capacious genius, and a
clofe way of reafoning. Had Longinus been an injudi¬
cious critic, had he not poffefled an exalted and beauti¬
ful genius, he would not have been fo fentible of Ploti¬
nus’s obfcurity : for no perfons complain lefs of the ob-
fcurity of a book,.than thofe whofe thoughts are con-
fufed and underftanding is fliallowT.” Martilius Ficinus,
at the requetl of Cofmo de Medicis, made a Latin ver-
lion of the works of Plotinus, with a fummary and ana-
lytis of each book ; which was printed at Bafd, firft by
xtfelf, in 1559, and afterwards with the Greek in 1580,
folio. His life was written by Porphyry, the moil il-
luttrious of his difciples.
PLOT US, or Darter, a genus of birds belonging
to the order Anseres. See Ornithology Index.
PLOUGH, in Agriculture, a machine for turning up
the foil by the adfion of cattle, contrived to fave the
time, labour, and expence, which, without this inftru-
ment, mutt have been employed in digging the ground,
and fitting it for receiving all forts of feed. See Agri¬
culture.
PLOUGHMAN, the perfon who guides the plough
in the operation of tilling.
PLOUGHING, in Agriculture, the turning up the
earth with a plough. See Agriculture,
PLOVER, the Englifh name of feveral fpecies of
Charadrius, Ornithology Index.
PLOWDEN, Edmund, ferjeant at law, defcended
from an ancient family in Shropthire, was born in 1517,
and was firtt a ftudent of the univerfity of Cambridge,
where he fpent three years in the tludy of philofophy
and medicine. He then removed to Oxford, where,
having continued his former ftudies about four years
more, in 1552 he was admitted to the practice of phytic
and furgery : but probably finding the praftice of the
art of healing lefs agreeable than the tludy, he entered
himfelf of the Middle Temple, and began to read law.
Wood fays, that in 1557 he was fummer reader to that
fociety, and Lent-reader three years after, being then
fergeant and oracle of the law. He died in the year
1584, aged 67 ; and was buried in the Temple church.
He wrote, 1. Commentaries or Reports of divers Cafes,
&c. in the reigns of King Edward VI. Queen Mary,
and Queen Elizabeth j London, 1571, 78, 99, 1613,
&c. Written in the old Norman language. 2. Que¬
ries, or a Moot-book of cafes, &c. tranflated, metho¬
dized, and enlarged, by H. B. of Lincoln’s-Inn. Lon¬
don, 1662, 8vo.
PLUCHE, Antony, a celebrated French writer,
was born at Rheims in 1688, and having ditlinguitlied
himfelf by his engaging manners and proficiency in the
belles-lettres, was appointed profeffor of humanity in the
univerfity of that city. Two years after he obtained
the chair of rhetoric, and was admitted into holy orders.
The bitliop of Laon (Clermont) informed of his talents, Pluche.
conferred upon him the direction of the college of his—v—”
epifcopal city. By his induttry and fuperior knowledge,
a proper order and fubordination foon took place in it j
but fome peculiar opinions refpecting the affairs of the
time difturbed his tranquillity, and obliged him to quit
his office. The intendant of Rouen, at the requetl of
the celebrated Rollin, entrufted him with the education
of his fon. Abbe Pluche having filled that place with
fuccefs and great honour to himfelf, left Rouen and
went to Paris, where, by the patronage of fome literary
friends and his own excellent writings, he acquired a
very dillinguithed reputation for learning. He publilh-
ed, 1. Le Spectacle de la Nature (Nature Difplayed), in
9 vols in 12mo. This work, which is equally intlruc-
tive and entertaining, is written with perfpicuity and
elegance j but the form of dialogue wdiich is adopted
lias rendered it rather prolix. The fpeakers, who are
the Prior, the Count, and Countefs, are not ditlinguith-
ed by any tlriking feature j but they have all the com¬
mon charadler, wffiich is tolerably pleating, not except¬
ing even that of the little chevalier de Breuil, wffio is,
however, a mere fcholar. This is the opinion wffiich
Abbe Desfontaines has formed of this work. Though
the author has given the converfations a pretty inge¬
nious turn, and even fome vivacity, yet nowr and then
they aflume the tone of the college. 2. Hijloire du
del, or Hitlory of the Heavens, in 2 vols in 12mo. In
this performance we find two parts almoft independent
of one another. The firtl contains fome learned inqui¬
ries into the origin of the poetic heavens. It is nearly
a complete mythology, founded upon ideas which are
new and ingenious. The fecond is the hitlory of the
opinions given by philofophers refpedling the formation
of the w’orld. The author thows the inutility, the incon-
ftancy, and uncertainty, of the motl etleemed fytlems j
and concludes with pointing out the excellence and fub-
lime fimplicity of the Mofaic account. Befides a noble
and well-turned expreffion, we find in it an erudition
which does not fatigue the mind. As to the foundation
of the fytlem explained in the firtl part, though it ap¬
pears extremely plaufible, wre will not take upon us to
fay how far it is true : Voltaire called it Fable du del,
or a Fable of the Heavens. 3. De Linguarum artificial
a work which he tranflated with this title, La Mecanique
des Langues, in 12mo. In this treatife he propofes a
ffiort and eafy method of learning languages, which is
by the ufe of tranflations intlead of themes or exercifes ^
his reflections on that fubjeCl are judicious and wrell ex-
preffed. 4. Harmony of the Pfalms and the Gofpel, or
a Tranflation of the Pfalms and Hymns of the Church,
with Notes relative to the Vulgate, the Septuagint, and
Hebrew Text, printed at Paris in 1764, in i2mo. In
1749, Abbe Pluche retired to Varenne St Maure,
where he gave himfelf up entirely to devotion and tludy.
Having become fo deaf that he could not hear without
the help of a trumpet, the capital afforded him little en¬
tertainment. It was in this retreat that he died of aa
apoplexy on the 20th of November 1761, at the age of
73 years. He poffeffed thofe qualities which form the
fcholar, the honetl man, and the Chriftian : temperate
in his meals, true to his word, an affeftionate parent, a
fenfible friend, and a humane philofopher ; he gave lef-
fons of virtue in his life as wTell as his writings. His
fubmiffion to all the dogmas of religion was very great.
Some
P L U [ 66r 1 P L U
Plachc Some Deirts having been furprifed that, in matters of
Plumbery think and fpeak like the vulgar, his an-
< v ^ ‘ fwer was, “ I glory in doing fo : It is infinitely more
rational to believe the word of God, than to follow the
glimmering lights of a reafon which is limited and fub-
jecl to error.”
PLUG, certain pieces of timber, formed like the
fruflum of a cone, and ufed to flop the haufe-holes and
the breaches made in the body of a Ihip by cannon¬
balls ; the former of which are called haufe-plugs, and
the latter Jhot-plugs, which are formed of various fizes
in proportion to the holes made by the different fizes of
fhot, which may penetrate the fliip’s fides or bottom in
battle } accordingly they are always ready for this pur-
pofe.
PLUKENE r, Leokard, a phyfician who flourifh-
ed in the reign of King Charles II. was one of the mod
excellent and laborious botanifts of that or any other
age. He was author of the Phytographia P/uhenetiana,
the Almagejlicum Britannicum, and other works of the
like kind, on which he fpent the greatefl part of his
life and fortune. His Phytography is mentioned with
the higheft encomiums in the Philofophical Tranfa&ions
for February 1696-7. His Opera Botanica, with cuts,
were printed at London in 6 vols folio, in 1 720.
PLUM-tree. See Prunes, Botany Index.
PLUMAGE, the feathers which ferve birds for a
covering. See Ornithology.
PLUMB-l ine, among artificers, denotes a perpendi¬
cular to the horizon} fo called, as being commonly
eredled by means of a plummet.
PLUMBAGO, Lead-wort j a genus of plants be¬
longing to the pentandria clafs. See Botany Index.
Plumbago, or B/ack-LEAB. See Graphite, Mi¬
neralogy Index.
PLUMBERY, the art of carting and working lead,
and ufing it in building.
As this metal melts foon and with little heat, it is eafy
to cart; it into figures of any kind, by running it into
moulds of brafs, clay, plafter, &c. But the chief article
in plumbery is fheets and pipes of lead ; and as thefe
make the balls of the plumber’s work, we fliall here
give the procefs of making them.
In Jheet-lead, a table or mould is made ufe of,
which confifts of large pieces of wood well jointed, and
bound with bars of iron at the ends; on the fides of
which runs a frame confifting of a ledge or border of
wood, three inches thick and four inches high from the
mould, called the fJjarps : The ordinary width of the
mould, within thefe (harps, is from four to five feet;
and its length is 16, 17, or 18 feet. This fhould be
fomething longer than the fheets are intended to be, in
order that the end where the metal runs off from the
mould may be cut off, becaufe it is commonly thin or
uneven, or ragged at the end. It muft ftand very even
or level in breadth, and fomething falling from the end
m which the metal is poured in, viz. about an inch or
an inch and a half in the length of 16 or 17 feet or
more, according to the thicknefs of the fheets wanted ;
for the thinner the fheet, the more declivity the mould
fhould have. At the upper end of the mould (lands
the pan, which is a concave triangular prifm, compofed
of two planks nailed together at right angles, and two
triangular pieces fitted in between them at the ends.
Ths length of this pan is the whole breadth of the
mould in which the (beets are caff 5 it Hands with its Plumber/,
bottom, which is a (harp edge, on a form at the end of
the mould, leaning with one fide againft it 5 and on the
oppofite fide is a handle to lift it up by, to pour out
the melted lead; and on that fide of the pan next the
mould are two iron hooks to take hold of the mould,
and prevent the pan from (lipping while the melted lead
is pouring out of it into the mould. This pan is lined
on the infide with moiftened fand, to prevent it from be¬
ing fired by the hot metal. The mould is alfo fpread
over, about two inches thick, with fand fifted and moiff-
ened, which is rendered perfe£lly level by moving over
it a piece of wood called a Jlrike, and fmoothing it over
with a fmoothing plane, which is a plate of poliihed'
brafs, about one fourth of an inch thick and nine inches
fquare, turned up on all the four edges, and with a
handle fitted on to the upper or concave fide. The fand
being thus fmoothed, it is fit for carting (beets of lead .
but if they would caff a ciftern, they meafure out the
bignefs of the four fides ; and having taken the dimdn-
fions of the front or fore-part, make mouldings by pref-
fing long (lips of wood, which contain the fame mould¬
ings, into the level fand •, and form the figures of birds,
beads, &c. by preffing in the fame manner leaden
figures upon it, and then taking them off, and at the <
fame time fmoothing the furface where any of the fand
is raifed up by making thefe impreflions upon it. The
reft of the operation is the fame in calling either cifterns
or plain (beets of lead. But before we proceed to men¬
tion the manner in which that is performed, it will be'
neceffary to give a more particular defeription of the
Jlrike. The ftrike, then, is a piece of board about five
inches broad, and fomething longer than the breadth of
the mould on the infide; and at each end is cut a notch
about two inches deep, fo that when it is ufed it rides
upon the (harps with thofe notches. Before they be¬
gin to caff, the ftrike is made ready by tacking on two
pieces of an old hat on the notches, or by (lipping a
cafe of leather over each end, in order to raife the un¬
der fide about one-eighth of an inch or fomething more
above the fand, according as they would have the (beet
to be in thicknefs; then they tallow the under edge of
the ftrike, and lay it acrofs the mould. The lead being
melted, it is put into the pan with ladles, in which,
when there is a fufficient quantity for the prefent pur-
pofe, the feum of the metal is fwept off with a piece of
board to the edge of the pan, letting it fettle on the
fand, which is by this means prevented from falling in¬
to the mould at the pouring out of the metal. When
the lead is cool enough, which muft be regulated ac¬
cording to the thicknefs of the (beets wanted, and is
known by its beginning to ftand with a (hell or wTall on
the fand round the pan, two men take the pan by the
handle, or elfe one of them lifts it by the bar and chain
fixed to a beam in the ceiling, and pour it into the
mould, while another man (lands ready with the ftrike,
and, as foon as they have done pouring in the metal,
puts on the mould, fweeps the lead forward, and draws
the overplus into a trough prepared to receive it. The
Iheets being thus call, nothing remains but to roll them -
up or cut them into any meafure wanted : but if it be
a ciftern, it is bent into four fides, fo that the two ends
may join the back, where they are foldered together 5
after which the bottom is foldered up.
The method of caJUng pipes without foldcring.—To
raakst
P L U [ 662 ] P L tr
Plumbery make tliefe pipes they have a kind of little mill, with
H . arms or levers to turn it withal. 1 he moulds are of
: I>!umier-( brafs, and confift of two pieces, which open and ihut by
means of hooks and hinges, their inward caliber or di¬
ameter being according to the lize of the pipe, ufually
two feet and a half. In the middle is placed a core or
round piece of brafs or iron, fomewhat longer than the
mould, and of the thicknefs of the inward diameter of
the pipe. This core is palled through two copper
rundles, one at each end of the mould, which they
ferve to clofe ; and to thefe is joined a little copper tube
about two inches long, and of the thicknefs the leaden
pipe is intended to be of. By means of thefe tubes, the
core is retained in the middle of the cavity of the mould.
The core being in the mould, with the rundles at its
two ends, and the lead melted in the furnace, they take
it up in a ladle, and pour it into the mould by a little
aperture at one end, made in the form of a funnel.
When the mould is full,, they pafs a hook into the end
of the core, and, turning, the mill, draw it out •, and then
opening the mould, take out the pipe. If they defire
to have the pipe lengthened, they put one end of it in
the lower end of the mould, and pafs the end of the
core into it; then (hut the mould again, and apply its
rundle and tube as before, the pipe juft caft ferving for
a rundle, &e. at the other end, Things being thus re¬
placed, they pour in freth metal, and repeat the opera¬
tion till they have got a pipe of the length required.
For making pipes of ftieet-lead, the plumbers have
wooden cylinders, of the length and thicknefs required }
and on thefe they form their pipes by wrapping the
ftieet around them, and foldering up the edges all along
them.
The lead which lines the Chinefe tea-boxes is reduced
to a thinnefs which we are informed European plumbers
cannot imitate. The following account of the proceis
by which the plates are formed was communicated to
a writer in the Gentleman’s Magazine by an intelligent
officer of an Eaft Indiaman. The carter fits by a pot con¬
taining the melted metal; and has two large ftones, the
under one fixed, the upper moveable, diieftly before
him. He raifes the upper ftone by preffing his foot
upon the fide of it, and with an iron ladle pours in the
opening a proper quantity of the fluid metal. He then
immediately lets fall the upper ftone, and by that means
forms the lead into a thin irregular plate, which is after¬
wards cut into a proper fhape. The furfaces of the
ftones, where they touch each other, are exactly ground
together.
PLUMBUM, Lead. See Lead, Chemistry /«-
dex.
Plumbum Corneum, or muriate of lead, a combina¬
tion of lead with muriatic acid. See Lead, Chemistry
Index.
PLUME, or Plumula, in Botany, the bud or germ.
See Gemma.
PLUMIER, Charles, a learned Minim, born at
Marfeilles, and one of the moft able botanifts of the
17 th century. He was inftrudted by the famous Maig-
nan, v/ho taught him mathematics, turnery, the art of
making fpectacles, binning-glafles, microfcopes, and
other w'orks. He at length went to Rome to perfedrt
himfelf in his ftudies, and there applied himfelf entirely
to botany under a flrilful Italian. At his return to
• ; 3
Provence, he fettled in the convent at Bornes, a man- Mumier
time place near Hieres, where he had the conveniency i !l
of making difcoveries in the fields with refpect to fim-, Fuiraiity-
pies. He was iome time after fent by the French king
to America, to bring from thence fuch plants as might
be of fervice in medicine. He made three different
voyages to the Antilles, and vifited the ifland of St
Domingo. The king honoured him with a penfion j
and he at laft fettled at Paris. However, at the
defire of M. Fagon, he prepared to go a fourth time to
America, to examine the tree which produces the Je-
fuits bark •, but died at the port of Santa Maria, near
Cadiz, in 1706. He wuote feveral excellent works; the
principal of which are. 1. A. volume of the Plants in the
American Iflands. 2. A Treatife on the American
Fern. 3. The Art of Turnery 5 a curious wTork embel-
liffied with plates.
PLUMMET, PlUMB-RuIc, or Plumb-line, an in-
ftrument ufed by carpenters, mafons, &cc. in order to
judge whether wulls, &c. be upright planes, horizontal,
or the like. It is thus called from a piece of lead,
fattened to the end of a cord, which ufually conftitutes
this inflrument. Sometimes the firing defeends along a
wmoden ruler, &c. raifed perpendicularly on another j
in which cafe it becomes a level.
PLUMM1NG, among miners, is the method of ufing
a mine-dial, in order to know the exadl place of the
work where to fink down an air-fhaft, or to bring an
adit to the w ork, or to know’ which way the load in¬
clines when any flexure happens in it.
It is performed in this manner : A fkilful perfon wfith
an afliilant, and with pen, ink, and paper, and a long
line, and a mine-dial, after his guefs of the place above
ground, defeends into the adit or w-ork, and there
fallens one end of the line to fome fixed thing in it 5
then the incited needle is let to reft, and the exa£l point
wdiei'e it refts is marked with a pen : he then goes on
farther in, the line ftill faftened, and at the next flexure
of the adit he makes a mark on the line by a knot or
otherwife : and then letting down the dial again, he
there likew'ife notes down that point at which the needle
Hands in this fecond pofition. In this manner he pro¬
ceeds, from turning to turning, marking down the
points, and marking the line, till he comes to the in¬
tended place : this done, he afeends and begins to work
on the iurface of the earth wThat he did in the adit,
bringing.the firft knot in the line to fuch a place where
the mark of the place of the needle will again anfwer
its pointing, and continues this till he come to the de-
fired place above ground, which is certain to be perpen¬
dicular over the part of the mine into which the air-fhaft
is to be funk.
PLUMOSE, fomething formed in the manner of a
feather, with a ftem and fibres iffuing from it on each
fide ; fuch are the antennae of certain moths, butter¬
flies, &c.
PLURAL, in Grammar, an epithet applied to that
number of nouns and verbs which is ufed when wre fpeak
of more than one thing. See Grammar.
PLURALITY, a diferete quality, confifting of two
or a greater number of the fame kind : thus wre fay, a
plurality of gods, &c. See the article Astronomy,
N0 157. for the arguments both for and againft a plu¬
rality of worlds.
Pluralitt
P L U
t 663 ]
P L U
Plurality. PlURALTTT of Benefices, or Livings, is where the
i^—~j fame ciei-^ is poffeffed of two or more fpiritual prefer-
tnents with cure of fouls. See BENEFICE.
The fmallnefs of fome benefices firfi: gave rife to plu¬
ralities j for an ecclcfiaftic, unable to fubfift on a Angle
one, was allowed to hold two j and at length the num¬
ber increafed without bounds. A remedy was attemptr
ed for this abufe at the council of Lateran under Alex¬
ander III. and Innocent III. in the year 1215, when
the holding more than one benefice was forbid by a ca¬
non under the penalty of deprivation ; but the fame
canon granting the pope a power to difpenfe with it in
favour of perlbns of diftinguifhed merit, the prohibition
became almoft ufelefs. They were alfo reltrained by
ifatute 21 Hen. VIII. cap. 13. which enafts, that if any
perfon having one benefice with cure of fouls, of the
yearly value of 81. or above (in the king’s books), ac¬
cept any other with cure of fouls, the firfi fhall be ad¬
judged in law to be void, &c. though the fame ftatute
provides for difpenfation in certain cafes.
In England, in order to procure a difpenfation, the
prefen tee muft obtain of the bifhop, in whofe diocefe
the livings are, two certificates of the values in the king’s
books, and the reputed values and diftance} one for the
archbilhop, and the other for the lord-chancellor. And
if the livings lie in two diocefes, then two certificates
of the fame kind are to be obtained from each bifliop.
He muft alfo (how the archbilhop his prefentation to
the fecond living ; and bring with him two teftimonials
from the neighbouring clergy concerning his behaviour
and converfation, one for the archbilhop and the other
for the lord-chancellor j and he muft alfo Ihow the arch¬
bilhop his letters of orders, and a certificate of his ha¬
ving taken the degree of mailer of arts at the leaft, in one
of the univerfities of this realm, under the hand of the
regifter. And if he be not do£lor or bachelor of divi¬
nity, nor doftor nor bachelor of law, he is to procure a
qualification of a chaplain, which is to be duly regiftered
in the faculty office, in order to be tendered to the
archbilhop, according to the ftatute. And if he hath
taken any of the aforefaid degrees, which the ftatute
allows as qualifications, he is to procure a certificate
thereof as already mentioned, and to Ihow the fame to
the archbilhop ; after which his difpenfation is made
out at the faculty office, where he gives fecurity accord¬
ing to the dire&ibn of the canon. He muft then repair
to the lord-chancellor for confirmation under the broad
fealand he muft apply to the bilhop of the diocefe
where the living lies for his admiffion and inftitution.
By the feveral ftamp a£ts, for every Ikin, or paper, or
parchment, &c. on which any difpenfation to hold two
ccclefiaftical dignities or benefices, or a dignity and a
benefice, lhall be engroffed or written, there lhall be paid
a treble 40s. ftamp duty.
We have alfo a regulation in regard to pluralities 5
but it is often difpenfed with : for, by the faculty of
difpenfation, a pluralift is required, in that benefice from
which he {hall happen to be moft abfent, to preach 13
fermons every year, and to exercife hofpitality for two
months' yearly.
In Germany the pope grants difpenfation for poffeffing
a plurality of benefices, on pretence that the ecclefiaftical
princes there need large revenues to bear up againft the
Proteftant princes.
PLUS, in Algebra, a chara&er marked thus -f-, ufed P
for the fign of addition. See Algebra. .
PLUSH, in commerce, &c. a kind of fluff, having ,
a fort of velvet knap or lhag on one fide, compofed re¬
gularly of a woof of a fingle woollen thread and a
double warp •, the one wool, of two threads twilled}
the other goats or camels hair though there are fome
plulhes entirely of worfted, and others compofed wholly
of hair.
'PLUTARCH, a great philofopher and hiftorian of
antiquity, who lived from the reign of Claudius to that
of Hadrian, was born at Chaeronea, a fmall citjr of Eceo-
tia in Greece. Plutarch’s family was ancient in Chaero-
nea : his grandfather Lamprias was eminent for his learn¬
ing and a philofopher j and is often mentioned by Plu¬
tarch in his writings, as is alfo his father. Plutarch
was initiated early in ftudy, to which he was naturally
inclined ; and was placed under the care of Ammonius,
an Egyptian, who, having taught philofophy with great
reputation at Alexandria, from thence travelled into
Greece, and fettled at Athens. Under this mailer he
made great advances in knowledge*, and like a thorough
philofopher, more apt to regard things than words, he
purfued this knowledge to the negleft of languages.
The Roman language at that time was not only the
language of Rome, but of Greece alfo : and much more
ufed there than the French is now in England. Yet
he was fo far from regarding it then, that, as we learn
from himfelf, he became not converfant in it till the
declenfion of his life : and, though he is fuppofed to
have refided in Rome near 40 years at different times,
^et he never feems to have acquired a competent Ikill
in it. But this Vras not the worft : he did not culti¬
vate his mother-tongue with any great exaftnefs} and
hence that harlhnels, inequality and obfeurity in his
ftyle, which has fo frequently and fo juftly been com¬
plained of.
After he was principled and grounded by Ammonius,
having an infatiable thirft for knowledge, he relolved to
travel. Egypt was at that time, as formerly it had
been, famous for learning *, and probably the myftericuf-
nefs of their doflrine might tempt him, as it had tempt¬
ed Pythagoras and others, to go and cOnverfe with the
priefthood of that country. This appears to'have been
particularly his bufinefs, by* his treatife Of Ifs and OJi~
ris: in which he {hows himfelf vevfed in the ancient
theology and philofophy of the wife men. From E-
gypt he returned into Greece *, and vifiting in his way
all the academies and fchools of the philofophers, ga¬
thered from them many of thofe obfervations with which
he has abundantly enriched pofterityn He does not
feem to have been attached io any particular fe£l, but
culled from each of them whatever he thought excel¬
lent and worthy to be regarded, He could not bear
the paradoxes of the Stoics, but yet was more averfe
from the impiety of the Epicureans: in many.things
he followed Ariftotle ; but his favourites were Socrates
and Plato, whofe memory he revered lo highly, that he
annually celebrated their birth-days with much folemni-
ty. Befides this, he applied himfelf with extreme di¬
ligence to colleft not only all books that were excellent
in their kind, but alfo all the fayings 'and obfervations
of wife men which he had heard in converfation or had
received from others by tradition 3 and likewife to con-
P L U
fult tlie records and public inflruments preferved in
cities which he had vilited in his travels. He took a
particular journey to Sparta, to fearch the archives of
that famous commonwealth, to underftand thoroughly
the model of their ancient government, the hiftory of
their legiilators, their kings, and their ephori j and di-
gefted all their memorable deeds and fayings with much
care. He took the fame methods with regard to many
other commonwealths j and thus was enabled to leave
us in his works fuch a rich cabinet of obfervation upon
men and manners, as, in the opinion of Montaigne and
Bayle, have rendered him the moft valuable author of
antiquity.
The circumftances of Plutarch’s life are not known,
and therefore cannot be related, with any exaftnefs. Ac¬
cording to the learned Fabricius, he was born under
Claudius, 50 years after the Chriftian era. He was
married to a moll amiable woman of his own native
town, whofe name, according to the probable conjec¬
ture of Rualdus, was Timoxena, and to whofe fenfe and
virtue he has borne the moft affectionate teftimony in
his moral works. He had leveral children, and among
them two fons •, one called Plutarch after himfelf, the
other Lamprias in memory of his grandfather. Lam-
prias was he, of all his children, who feems to have in¬
herited his father’s philofophy j and to him we owe the
table or catalogue of Plutarch’s writings, and perhaps
alfo his apophthegms. He had a nephew, Sextus Chas-
roneus, who taught the learned emperor Marcus Aure¬
lius the Greek tongue, and was much honoured by him.
Some think, that the critic Longinus was of his family ;
and Apuleius, in the firft book of his Metamorphofes,
affirms himfelf to be defcended from him.
On what occahon, and at what time of his life, he
went to Rome, how long he lived there, and when he
finally returned to his own country, are all uncertain.
It is probable, that the fame of him went thither before
him, not only becaufe he had publiffied feveral of his
works, but becaufe immediately upon his arrival, as
there is reafon to believe, he had a great refort of the
Roman nobility to hear him : for he tells us himfelf,
that he was fo taken up in giving leftures of philofophy
to the great men of Rome, that he had not time to
make himfelf mafter of the Latin tongue, which is one
of the firft things that would naturally have engaged
his attention. It appears that he was feveral times at
Rome and perhaps one motive for his living there
was the intimacy he had contraCled in fome of thefe
journeys with Soilius Senecio, a great and worthy man,
who had been four times conful, and to whom Plutarch
has dedicated many of his lives. But the great induce¬
ment which carried him firft to Rome, was undoubt¬
edly that which had carried him into fo many other
parts of the world } namely, to make obfervations upon
men and manners, and to colled materials for writing
the lives of the Roman worthies, in the lame manner as
he had already written thofe of the Grecian : and ac¬
cordingly he not only converfed with all the living, but
fearched the records of the Capitol, and of all the libra¬
ries. Not but, as we learn from Suidas, he was intruft-
ed alfo with the management of public affairs in the
empire, during his refidence in the metropolis. “ Plu¬
tarch (fays he) lived in the time of Trajan, who be¬
llowed on him the confular ornaments, and alfo caufed
an edid to be paffed, that the magiftvates or officers of
4
P L U
Illyria ftiould do nothing in that province without his Plutarch,
knowledge and approbation.” Pluto.
When and how he was made known to Trajan is J-“ “
likewife uncertain : but it is generally fappofed that
Trajan, a private man when Plutarch firft came to
Rome, was, among other nobility, one of his auditors,
It is alfo fuppofed, that this wife emperor made ufe of
him in his councils ; at leaft, much of the happinefs of
his reign has been imputed to Plutarch. Fabricius af-
ferts that he was Trajan’s preceptor, and that he was
raifed to the confular dignity by him, and made procu¬
rator of Greece in his old age by the emperor Adrian.
We are equally at a lofs concerning the time of his
abode in the imperial city j which, however, at different
times, is not imagined to fall much ffiort of 40 years.
The defire of vifiting his native country, fo natural to
all men, and efpecially when growing old, prevailed
with him at length to leave Italy : and at his return he
was unanimoufly chofen archon or chief magiftrate of
Chaeronea, and not long after admitted into the num¬
ber of the Delphic Apollo’s priefts. WT have no par¬
ticular account of his death, either as to the manner of
it or the year } only it is evident that he lived, and
continued his ftudies, to a good old age. The moft
probable conje&ure is that of Fabricius, who fays he
died in the fifth year of Adrian, at the age of 70.
His works have been divided, and they admit of a
pretty equal divifion, into Lives and Morals : the for¬
mer of which, in his own eftimation, were to be prefer¬
red as more noble than the latter. His ftyle, as we
have already obferved, has been excepted to with fome
reafon : he has alfo been criticifed for fome miftakes in
Roman antiquities, and for a little partiality to the
Greeks. On the other hand, he has been juftly praifed
for the copioufnefs of his fine fenfe and learning, for
his integrity, and for a certain air of goodnefs which
appears in all he wrote. His bufinels was not to pleafe
the ear, but to inftrudt and charm the mind ; and in
this none ever went beyond him. Of his moral wri¬
tings it is to be regretted that we have no elegant Eng-
liffi tranflation. Even his Lives were chiefly known
to the Englifh reader by a motley and miferable verfion,
till a new one executed with fidelity and fpirit was pre-
fented to the public by the Langhornes in T770. On
the whole, it is to be wiflied that this moft amiable mo-
ralift and biographer had added a life of himfelf to thofe
which he has given to the world of others, as the parti¬
culars which other writers have preferved of his perfonal
hiftory are very doubtful and imperfect.
PLUTO, in Pagan worftrip, the king of the infer¬
nal regions, was the fon of Saturn and Ops, and the
brother of Jupiter and Neptune. This deity finding
himfelf childlefs and unmarried, mounted his chariot to
vifit the world ; and arriving in Sicily, fell in love with
Proferpine, whom he faw gathering flowers with her
companions in the valley of Lima, near Mount Altna :
when, forcing her into his chariot, he drove her to the,
river Chemarus, through which he opened himfelf a paf-
fage back to the realms of night. See Ceres and Pro¬
serpine.
Pluto is ufually reprefented in an ebony chariot drawn
by four black horfes; fometimes holding a feeptre, to
denote his power ; at others, a wand, with which he
drives away the ghofts *, and at others, fome keys, to
fignify that he had the keys of death. Homer obferves,
[ 6S4 ]
PLY [ 665 ] PL Y
Pluto that his helmet had the quality of rendering the wearer
I! invilible, and that Minerva borrowed it in order to be
« ^>u'1*. concealed from Mars when die fought againft the Tro¬
jans. Pluto wTas greatly revered both by the Greeks
and Romans, who eredted temples and altars to him. To
this god facrinces were offered in the night, and it was
not lawful to offer them by day.
PLUTUS, in Pagan worfhip, the god of riches, is
frequently confounded with Pluto. He was reprefented
appearing lame when he approached, and with wings
at his departure j to fliow the difficulty of amaffing
wealth, and the uncertainty of its enjoyment. He was
alfo frequently reprefented blind, to fliow that he often
bellowed his favours on the moll unworthy, and left in
neceffity thofc who had the greateft merit.
PLUVTALIS, a fpecies of plover. See Chara-
dril'S, Ornithology Index.
PLUVIUS, a furname of Jupiter. He was invoked
by that name among the Romans whenever the earth
was parched up by continual heat, and was in want of
refrefliing rains. He had an altar in the temple on the
capitol.
FLYERS, in fortification, denote a kind of balance
ufed in raifing or letting down a draw-bridge. They
confift of two timber levers, twice as long as the bridge
they lift, joined together by other timbers framed in the
form of a St Andrew’s crofs to counterpoife them.
They are fupported by two upright jambs, on which
they fwing ^ and the bridge is railed or let down by
means of chains joining the ends of the plyers and
bridge.
PLYING, in the fea language, the a£t of making,
©r endeavouring to make, a progrefs againfl the direc¬
tion of the wind. Hence a (hip that advances well in
her courfe in this manner of failing, is faid to be a good
plyer. See the articles Beating, Pitching, and Tack-
' ING.
PLYMOUTH, a town of Devonffiire, in England,
about 215 miles from London, Hands between the rivers
Plym and Tamar, juft: before they fall into the Britiffi
channel. From a mere filhing village it has become
one of the largeft towns in the county; and is one of
the chief magazines in the kingdom, on account of its
port, which is one of the fafeft in England, and which
is fo large as to be able to contain 1000 fail. It is de¬
fended by feveral different forts, mounting altogether
nearly 300 guns ; of which the chief is the Royal Cita¬
del, eredled in the reign of Charles II. oppofite to St
Nicholas ifland, which is within the circuit of its wTalls,
and contains a large ftore-houfe and five regular baf-
tions. In time of w7ar the outward-bound convoys ge¬
nerally rendezvous at Plymouth, and homeward-bound
fnips generally put in to provide pilots up the Channel.
It is alfo a great place of refort for men of war that are
wind-bound.
The mouth of the Tamar is called Ham-Ooze, and
that of Plym Catwrater, which are both commanded by
the caftle on St Nicholas ifland. About twr<-» miles up
the mouth of the Tamar there are four docks, two of
which were built in the reign of William III. one wet
and the other dry, and two wffiich have been built fince.
They have every conveniency for building or repairing
fliips.. One of the docks is hewn out of a mine of flate,
and lined with Portland ftone. This town enjoys a
pilchard fifliery of confiderable importance, and carries
Vol. XVI. Part II.
on an extenfive trade with Newfoundland and the Straits. P!} mouth.
There is a cuftomhoufe in it j and though there are twol| ','1' *' J
churches (and befides feveral meeting-houfes), yet each
church has fo large a cure of fouls, that the parifh clerks
w^ere till very lately in deacons orders, to enable them
to perform all the occafional and other offices. The
feat-rents are given to the poor. The lecturers are
chofen every three years by the corporation, which was
conftituted by Henry VI. and confifts of a mayor, 12
aldermen, and 24 common-council men. The mayor
is ele&ed by a jury of 36 perfons, chofen by four others,
twm of whom are appointed by the mayor and aldermen,
and the other two by the common-council. There is .
alfo a recorder, and a town-clerk, whofe place is very
profitable. The town confifts of four divifions, which
were anciently governed by four captains, each of whom
had three conftables under him. It is wrell fupplied
with freffi water, which was brought from the diftance
of feven miles, by Sir Francis Drake a native of the
town. The toll of the markets, and of the cotton,
yarn, &c. with the profit of the mill, which very
confiderable, belongs to the corporation, as do the re¬
venues of the ffiambles, which are farmed out for the
mayor’s kitchen. There is a charity-fchool in Plymouth,
four hofpitals, and a workhoufe, in all which 100 poor
children are clothed, fed, and taught 5 and there are
two printing-houfes. To one of the hofpitals Colonel
Jory gave a charity for 1 2 poor widows, as he did a
mace worth 120I. to be carried before the mayor, and
fix good bells, valued at 500I. to Charles-Churcb, fo
called from our kings in whofe reigns it wTas begun and
finifhed. In the entrance of the bay lies the famous
Eddyftone rock, wffiich is covered at high w ater, and on
which the ingenious Mr Winftanley built a light-houfe,
that was blorvn dowm in the terrible hurricane of Nov.
27th 1703, and himfelf, with others that were with
him in it, never more heard of. However, another was
ereffed in the room of it, by the corporation of the
Trinity-houfe, in the time of Queen Anne, which was
deftroyed by an accidental fire Dec. 4th 1795, but re¬
built in 1759 : which alfo was burnt down, and rebuilt
by the celebrated Smeaton in the year 1770. In the
reign of Edward III. the French landed, and burnt
part of the town, but were foon repulfed by Hugh
Courtenay earl of Devon. In the reign of Henry IV.
the French landed here again, and burnt 600 houfes.
Between this town and the fea is a hill called the Haw,
which has a delightful plain on the top, having a plea-
fant profpeft all round it, and a good landmark for the
ufe of mariners. The lift of parliament-men for this
borough, formerly divided into tw^o parts, by the names
of Sutton-Valtort and Sutton-Prior, commences the 26th
of Edward I. and continues to the 14th of Edward III.
after which w^e find no return made for it till the 20th
of Henry VI. wffien the privilege was renewed. On the
Haw is a fort, wffiich at once commands the towm and de¬
fends the harbour. Here is a ferry over the Tamar, called
CrumwTell or Crimble Paffage, the w^eft fide of which is
called Weftone-Houfe, and is in Devonffiire, though
moft of the parifh wherein it Hands is in Cornwall. In
April 1759 parliament granted 25,159!. for the better
fortifying the towm and dock of Plymouth. N. Lat. 50.
26. W. Long. 4. 1 5.
Plymouth, in New England, a fea-port town, and
capital of the county of the fame name, in the province
4 ef
PLY [ 666 ] PLY
Plymouth, 0f Maflachufets Bay, in North America. It is remark-
. Fv'ntcna- able for having been the firft fettlement in New Eng¬
land, and for having had the firft place of worlhip. It
is feated at the fouth end of Plymouth bay. W. Long.
70. 10. N. Lat. 41. 58.
PLYNTERIA, a Grecian feftival in honour of
Aglauros, or rather of Minerva, who received from the
daughter of Cecrops the name of Aglauros. The word
is derived from TrXwii*, lavare, becaufe during the folem-
nity they undreffed the ftatue of the goddefs and walked
it. I he day on which it was obferved wTas looked up¬
on as unfortunate and inaufpicious j and therefore no Plynteria.
perfon was permitted to appear in the temples, as they v—f
were purpofely furrounded with ropes. The arrival of
Alcibiades in Athens that day wras thought very unfor¬
tunate, but the fuccefs that ever after attended him
proved it to be othemife. It was cultomary at this fef-
tival to bear in proceffion a duller of figs j which in¬
timated the progrefs of civilization among the firft inha¬
bitants of the earth, as figs ferved them for food after
they had found a dillike for acorns.
PNEUMATICS.
Definition 'T ’HIS term is rellri&ed, in the prefent habits of our
of the term. language, to that part of natural philofophy which
treats of the mechanical properties of elaftic fluids. The
word, in its original meaning, exprefies a quality of air,
or more properly of breath. Under the article Physics
we obferved, that in a great number of languages the
term ufed to exprefs breath wTas alfo one of the" terms
ufed to exprefs the animating principle, nay, the intel¬
lectual fubftance, the foul. It has been perhaps owing
to fome attention to this chance of confufion that our
philofophers have appropriated the term Pneumatics to
the fcience of the mechanical properties of air, and Pneu-
MAtology to the fcience of the intellectual phenomena
confequent on the operations or affeCtions of our think-
* ing principle.
Extent of We have extended (on the authority of prefent cuf-
the icience. tom) tjie term pNEUMATICS to the ftudy of the me¬
chanical properties of all elaltic or fenfibly compreOible
fluids, that is, of fluids whofe elafticity and comprefli-
bility become an interefting objeCt of our attention ; as
the term Hydrostatics is applied to the Itudy of the
mechanical properties of fuch bodies as interelt us by
their fluidity or liquidity only, or whofe elafticity and
compreflibility are not familiar or interefting, though
not lefs real or general than in the cafe of air and all
vapours.
No precife ^e may be indulged in the obfervation by the bye,
limit to the fhat there is no precife limit to the different claffes of
different natural bodies with refpeCt to their mechanical proper-
elaffes of tIes> There is no fuch thing as a body perfectly hard,
0 !e!,‘ perfectly foft, perfectly elaftic, or perfectly incompref-
fible. All bodies have fome degree of elafticity inter¬
mixed with fome degree of duCtility. Water, mercury,
oil, are compreflible 5 but their compreflibility need not
be attended to in order perfectly to underftand the phe¬
nomena confequent on their materiality, fluidity, and
gravity.. But if we negleCl the compreflibility of air,
we remain ignorant of the caufe and nature of its moft
interefting phenomena, and are but imperfeCtly informed
with refpeCt to thofe in which its elafticity has no fhare ;
and it is convenient to attend to this diftinCtion in our
refearches, in order to underftand thofe phenomena
which depend ftdely or chiefly on compreflibility and
elafticity. This obfervation is important j for here ela¬
fticity appears in its moft Ample form, unaccompanied
with any other mechanical affeCtion of matter (if we
except gravity), and lies moft open to our obfervation,
whether employed for inveftigating the nature of this
very property of bodies, or for explaining its mode of
aCtion. We ftiall even find that the conftitution of art.
avowedly elaftic fluid, whofe compreflibility is fo very
fenfible, will give us the diftinCteft notions of fluidity
in general, and enable us to underftand its chara&eriftic
appearances, by which it is diftinguifhed from folidity,
namely, the equable diftribution of preffure through all
its parts in every direction, and the horizontality which
its furface afliimes by the aCtion of gravity : phenomena
which have been afllimed as equivalent to the definition
of a perfeCt fluid, and from which all the law’s of hydro-
ftatics and hydraulics have been derived. And thefe
laves have been applied to the explanation of the pheno¬
mena around us j and water, mercury, oil, &c. have
been denominated fluid only becaufe their appearances
have been found to tally exaCtly with thefe confequences
of this definition, while the definition itfelf remains in
the form of an aflumption, unfupported by any other
proof of its obtaining in nature. A real mechanical
philofopher wall therefore attach himfelf w’ith great ea-
gernefs to this property, and confider it as an introduc¬
tion to much natural fcience.
Of all the fenfible compreflible fluids air is the moft ^jr tj^
familiar, was the firft Itudied, and the moft minutely moft farai-
examined. It has therefore been generally taken as the har corn-
example of their mechanical properties, while thofe me- Pre.^le
chanical properties w’hich are peculiar to any of them,1
and therefore charaCteriftic, have ufually been treated
as an appendix to the general fcience of pneumatics.
No objection occurs to us againft this method, which
will therefore be adopted in treating this article.
But although the mechanical properties are the pro Different
per fubjeCts of our confideration, it will be impoflible properties
to avoid confidering occafionally properties which are °*
more of a chemical nature ; becaufe they occafion fuch
modifications of the mechanical properties as would fre¬
quently be unintelligible without confidering them in
conjunction with the other ; and, on the other hand,
the mechanical properties produce fuch modifications of
the properties merely chemical, and of very interefting
phenomena confequent on them, that thefe would often
pafs unexplained unlefs we give an account of them in
this place. ^
By mechanicalproperties we wmuld be underltood to Mechanical
mean fuch as produce, or are connected with, fenfible properties,
changes of motion, and which indicate the prefence and
agency @f moving or mechanical powers. They are
therefore the fubjeCt of mathematical difeuflion 3 admit-
ting
PNEUMATICS.
657
^What is
air ?
Proofs
that it is
matter,
.Plate
ting of meafure, number, and direction, notions purely
mathematical.
We fhall therefore begin with the confideration of
air.
It is by no means an idle queftion, “ What is this air
of which fo much is faid and written ?” We fee no¬
thing, we feel nothing. We find ourfelves at liberty to
move about in any direction without any let or hin-
derance. Whence, then, the affertion, that we are fur-
rounded with a matter called air ? A few very fimple
obfervations and experiments will fhow us that this affer¬
tion is well founded.
We are accuftomed to fay, that a veffel is empty
when we have poured out of it the water which it con¬
tained. Take a cylindrical glafs jar (fig. I.), having
ccccxxni. a fmall hole in its bottom ; and having flopped this hole,
Fig- i- fill the jar with water, and then pour out the water,
leaving the glafs empty, in the common acceptation of
the word. Now, throw a bit of cork, or any light
body, on the furface of water in a ciftern : cover this
with the glafs jar A held in the hand with its bottom up¬
wards, and move it downwards, as at B, keeping it all
the while in an upright pofition. The cork will continue
to float on the furface of the water in the infide of the
glafs, and will moft dillififtly (how whereabouts that fur-
race is. It will thus be fben, that the water within the glafs
has its furface confiderably lower at C than that of the fur¬
rounding water; and however deep we immerge the glafs,
we- fliall find that the water wfill never rife in the infide
of it fo as to fill it. If plunged to the depth of 32 feet,
the water will only half fill it; and yet the acknowledg¬
ed laws of hydroftatics tell us, that the water would fill
the glafs if there were nothing to hinder it. There is
therefore fomething already within the glafs which pre¬
vents tlie water from getting into it-, manifefting in this
manner the moft diftimflive property of matter, viz. the
hindering other matter from occupying the fame place at
9 the fame time.
Pofiefied of While things are in this condition, pull the ftopper
impulfive J) out of the hole in the bottom of the-jar, and the water
force, will inftantly rife in the infide of the jar, and ftand at an
equal height within and without. This is juftly aferibed
to the efcape through the hole of the matter which for¬
merly obftru&ed the entry of the water; for if the hand
be held before the hole, a puff will be diftinftly felt, or a
feather held there will be blown afide j indicating in this
manner that what prevented the entry of the water, and
now efcapes, poffeffes another charadteriftic property of
matter, impuljive force. The materiality is concluded
from this appearance, in the fame manner that the mate¬
riality of water is concluded from the impulfe of a jet
from a pipe. We alfo fee the mobility of the formerly
pent up, and now liberated, fubftance, in confequence
of external preffure, viz. the preffure of the furrounding
io water.
Impenetra- Alfo, if we take a fmooth cylindrical tube, fliut at
feility, one end, and fit a plug or cork to its open end, fo as
to Aide along it, but fo tightly as to prevent all paffage
by its fides -, and if the plug be well foaked in greafe,
we fliall find that no force whatever can pufh it to the
bottom of the tube. There is therefore fomething with¬
in the tube preventing by its impenetrability the entry
of the plug, and therefore poffefling this chara&eriftic
jj of matter.
ElalUcity, In lil^e manner, if, after having opened a pair of com¬
mon bellow's, we flmt up the nozzle and valve hole, and
try to bring the boards together, w-e find it impoffible.
There is fomething included which prevents this, in the
fame manner as if the bellows were filled with wool > but
on opening the nozzle we can eafily ftiut them, viz. by
expelling this fomething 5 and if the compreflion be for¬
cible, the fomething will iffue with confiderable force, and
very fenfibly impel any thing in its way. Jt
It is not accurate to fay, that wre move about wdth- inertia, and
out any obftruftion : for we find, that if we endeavour mobility*
to move a large fan with rapidity, a very fenfible hin-
derance is perceived, and that a very fenfible force muft
be exerted j and a fenfible wind is produced, which wall
agitate the neighbouring bodies. It is therefore juftly
concluded that the motion is poflible only in confequence
of having driven this obftrufting fubftance cut of the way j
and that this impenetrable, refitting, moveable, impelling
fubftance, is matter. We perceive the perfeverance of
this matter in its ftate of reft when we wave a fan, in
the fame manner that wTe perceive the inertia of water
when we move a paddle through it. The effedts of wrind
in impelling our thips and mills, in tearing up trees, and
overturning buildings, are equal indications of its perfe-
verance in a ftate of motion.
To this matter, when at reft, we give the name Air j
and when it is in motion we call it Wind. I3
Air, therefore, is a material fluid: a fluid, becaufelt isthere-*
its parts are eafily moved, and yield to the fmalleft in- for5 a raa-
equality of preffure. terial
Air poffeffes feme others of the very general, though T4
not fffential, properties of matter. It is heavy. ThisHeavy’ aB“'
appears from the following facts. B
1. It always accompanies this globe in its orbit round
the fun, furrounding it to a certain diftance, under the
name of the Atmosphere, which indicates the being
connected with the earth by its general force of gravity.
It is chiefly in confequence of this that it is continually
moving round the earth from eaft to weft 5 forming what
is called the trade-wind, to be more particularly^ con-
fidered afterwards. All that is to be obferved on this
fubjeft at prefent is, that, in confequence of the dif-
turbing force of the fun and moon, there is an accumu¬
lation of the air of the atmofphere, in the fame manner
as of the waters of the ocean, in thofe parts of the
globe which have the moon near their zenith or nadir
and as this happens fucceflively, going from the eaft to
the w-eft (by the rotation of the earth round its axis in
the oppofite dire&ion), the accumulated air muft gra¬
dually flow along to form the elevation. This is chiefly
to be obferved in the torrid zone ; and the generality
and regularity of this motion are greatly difturbed by i
the changes which ^re continually taking place in differ¬
ent parts of the atmofphere from caufes which are not
mechanical. ^
2. It is in like manner owing to the gravity of the fupports
air that it fupports the clouds and vapours'w'hich we the clouds,
fee conftantly floating in it. We have even feen bodies
of no inconfiderable weight float, and even rife, in the
air. Soap bubbles, and balloons filled wdth inflammable
gas, rife and float in the fame manner as a cork rifes in
w'ater. This phenomenon proves the weight of the aif,
in the fame manner that the fwimming of a piece of
w'ood indicates the weight of the water which fup-' l6
ports it. Familiar
3. But we are not left to thefe refined obfervations Proofs of
4 P 2 fer weiSht-
668
PNEUMATICS.
for the proof of the air’s gravity. We may obferve fa¬
miliar phenomena, which would be immediate confe-
quences of the fuppofition that air is a heavy fluid, and,
like .ether heavy fluids, preffes on the outfides of all
bodies immerfed in or furrounded by it. Thus, for
iuftance, if we fhut the nozzle and valve hole of a pair
of bellows after having fqueezed the air out of them,
we {hall find that a very great force, even fome hundred
pounds, is neceffary for feparating the boards. They
arc kept together by the preffure oi the heavy air which
furrounds them in the fame manner as if they were im¬
merfed in water. In like manner, if we flop the end
of a fyringe after its pifton has been prefled down to the
bottom, and then attempt to draw up the piflon, we
{hall find a confiderable force neceffary. viz. about 15
or 16 pounds for every fquare inch of the fehfion of the
fyringe. Exerting this force, we can draw up the piflon
to the top, and we can hold it there j but the moment
we ceafe a fling, the piflon ruflies down and ftrikes the
bottom. It is called a fuftion, as we feel fomething as
it were drawing in the pifton ; but it is really the weight
of the incumbent air prefling it in. And this obtains
in every pofition of the fyringe 5 becaufe’ the air is a
fluid, and prefl'es in every direction. Nay, it preffes on
the fyringe as well as on the piflon •, and if the pifton
be hung by its ring on a nail, the fyringe requires force
to draw it down (juft as much as to draw the pifton up) ;
ccccxxiu. anc^ ^ ^ 1iet §°> ^ fpJ'ing UP> unlefs loaded with
Fig. 2. at leaft 15 pounds for every fquare inch of its tranfverfe
l7 feflion (fee fig. 2.).
It m.iy 4. But the moft direfl proof of the weight of the air
even be is had by weighing a veffel empty of air, and then
weighed, weighing it again when the air has been admitted ;
and this, as it is the moft obvious confequence of its
weight, has been afferted as long ago as the days of
Ariftotle. He fays (!!«$/ iv. 4.), That all bo¬
dies are heavy in their place except fire ; even air is
heavy j for a blown bladder is heavier than when it is
empty. It is fomewhat furprifing that his followers
Ihould have gone into the oppofite opinion, while pro-
feffing to maintain the doflrine of their leader, if we
take a very large and limber bladder, and fqueeze out
the air very carefully, and weigh it, and then fill it till
the wrinkles juft begin to difappear, and w7eigh it again,
we {hall find no difference in the weight. But this is
not Ariftotle’s meaning ; becaufe the bladder, confider-
ed as a veffel, is equally full in both cafes, its dimenfions
being changed. We cannot take the air out of a blad¬
der without its immediately collapfing. But what would
be true of a bladder would be equally true of any veffel.
Tig. 3. Therefore, take a round veffel A (fig. 3.), fitted with
a ftopcock B, and fyringe C. Fill the ■whole with
water, and prefs the pifton to the bottom of the fyringe.
Then keeping the cock open, and holding the veffel up¬
right, with the fyringe undermoft, draw7 down the pifton.
The water will follow it by its weight, and leave part of
the veffel empty. Now fliut the cock, and again pufh up
the pifton to the bottom of the fyringe; the water efcapes
through the pifton valve, as wall be explained aftemard:
then opening the cock, and again drawing dowm the pi¬
fton, more water will come out of the veffel. Repeat this
operation till all the water have come out. Shut the cock,
unferew the fyringe, and weigh the veffel very accurate¬
ly. Now open the cock, and admit the air, and wreigh
the veffel again, it will be found heavier than before, and
this additional weight is the weight of the air which fills
it; and U will be found to be 523 grains, about an ounce
and a fifth avoirdupois, for every cubic foot that the vtffel
contains. Now fince a cubic foot of water would weigh
1000 ounces, this experiment wmuld {how that water is
about 840 times heavier than air. The moft accurate
judgement of this kind of which wre have met with an
account is that recorded by Sir George Shuckburgh,
which is in the 67th vol. of the Philoiophical Tran fac¬
tions, p. 560. From this it follows, that when the air
is of the temperature 53, and the barometer Hands at
29! inches, the air is 836 times lighter than water.
But the experiment is not fufceptible of fufficient accu¬
racy for determining the exact weight of a cubic foot of
air. Its weight is very fmall 5 and the veffel muft be
ftrong and heavy, fo as to overload any balance that is
fuificiently nice for the experiment.
To avoid this inconvenience, the whole may be The moft
weighed in water, firlt loading the veffel fo as to makeconwn‘fcnt
it preponderate an ounce or two in the water. By this trie.t^0^,0^
means the balance will be loaded only with this fmall<luin^ t lS*
preponderancy. But even in this cafe there are confi¬
derable fources of error, arifing from changes in the
fpecific gravity of the water and other caufes. The
experiment has often been repeated with this view, and
the air has been found at a medium to be about 840
times as light as water, but with great variations, as
may be expe&ed from its very heterogeneous nature, in
confequence of its being the menftruum of almoft every
fluid, of all vapours, and even of molt folid bodies 5 all
which it holds in folution, forming a fluid perfectly
tranfparent, and of very different denfity according 1o
its compofition. It is found, for inftance, that pertedt-
ly pure air of the temperature of our ordinary fummer
is confiderably denier than when it has diffoived about
half as much water as it can hold in that temperature ;
and that with this quantity of water the difference of
denfity increafes in proportion as the mafs grows warmer,
for damp air is more expanfible by heat than dry air.
We have had occafion to confider this fubject when
treating of the connexion of the mechanical properties
of air wfith the ftate of the weather. See Meteoro¬
logy.
19
Such is the refult of the experiment fuggefted by This pro-
Ariftotle, evidently proving the weight of the air j and Perty °f
yet, as has been obferved, the Peripatetics, who profefs |ur ^
to follow the diclates of Ariftotle, uniformly refufed it ftpatetics,'
this property. It w7as a matter long debated among though ac-
the philofophers of the laft century. The reafon was, knowlcdg-
that Ariftotle, wfith that indiftindtnefs and inconfiftency,ed tdie*r
which is obferved in all his writings which relate to
matters of fa£t and experience, afligns a different caufe
to many phenomena which any man led by common
obfervation w7ould aferibe to the weight of the air. Of
this kind is the rife of w7ater in pumps and fyphons,
which all the Peripatetics had for ages aferibed to fome¬
thing wfliich they called nature’s abhorrence of a void.
Ariftotle had afferted (for reafons not our bufinefs to
adduce at prefent), that all nature wras full of being,
and that nature abhorred a void. He adduces many
fa£ts, in which it appears, that if not abfolutely impof-
fible, it is very difficult, and requires great force, to
produce a fpace void of matter. When the operation
of pumps and fyphons came to be known, the philofo¬
phers of Europe : (who had all embraced the Peripatetic
dodtrines)
0
2@
Confixuc-
tion of
pumps in
the la It
century.
Frg. 4.
2t
Their ope¬
ration ac¬
counted
for by the
Peripate¬
tics.
P N E U M
cto&rines) found in this fancied horror of a fancied mind
(what elie is this that nature abhors ?) a ready folution
of the phenomena. We (hall if ate the fails, that every
reader may fee what kinds of reafoning were received
among the learned not two centuries ago.
Pumps were then conltrucled in the following man¬
ner : A long pipe GB (fig. 4.) was fet in the water
of the well A. This was fitted with a fucker or piiton
C, having a long rod CF, and was furniihed with a
valve B at the bottom, and a lateral pipe DE. at the
place of delivery, alfo furniihed with a valve. The tail
is, that if the pilfon be thruft dow;n to the bottom, and
then drawn up, the wrater will follow it 5 and upon the
pifton being again pulhed down, the water Units the
valve B by its weight, and efcapes or is expelled at the
valve E ; aad on drawing up the pifton again the valve
E is Ihut, the water again rifes after the pifton, and is
again expelled at its next defcent.
The Peripatetics explain all this by faying, that if
the water did not follow the pijlon there would be a void
between them. But nature abhors a void ; or a void
is impoftible : therefore the water follows the pifton.—
It is not worth while to criticife the wretched reafoning
in this pretence to explanation. It is all overturned by
one obfervation. Suppofe the pipe Ihut at the bottom,
the pifton can be drawn up, and thus a void produced.
No, fay the Peripatetics; and they fpeak of certain fpi-
rits, effluvia, &c. which occupy the place. But if fo,
wiiy needs the water rife ? This therefore is not the
caufe of its afcent. It is a curious and important pheno¬
menon.
Galileo firft fugacious Galileo feems to have been the firft who
accounted ferioufly afcribed this to the weight of the air. Many
for it ra- before him had fuppofed air heavy 5 and thus explained
the difficulty of railing the board of bellows, or the pi¬
fton of a fyringe, &c. But he diftimftly applies to this
allowed weight of the air all the confequences of hydro-
ftatieal laws; and he reafons as follows.
The heavy air refts on the water in the ciftern, and
preffes it with its weight. It does the fame with the
water in the pipe, and therefore both are on a level :
but if the pifton, after being in contact with the liirface
of the water, be drawn up, there is no longer any pref-
fure on the furface of the water within the pipe 5 for
the air now refts on the pifton only, and thus occalions a
difficulty in drawing it up. The water in tlwr'jtipe,
therefore, is in the fame fituation as if more water were
poured into the ciftern, that is, as much as would exert
the fame preffure on its furface as the air does. In this
cafe we are certain that the water will be preffed into
the pipe, and will raife up the water already in it, and
follow it till it is equally high within and without. The
fame preflure of the air Ihuts the valve E during the de¬
fcent of the pifton. (See Gal. Difcourfesf
He did not wait for the very obvious objeefion, that
if the rife of the water was the effeff of the air’s preffure,
it would alfo be its meafure, and would be raifed and
fupported only to a certain height. He direflly faid fo,
and adduced this as a decilive experiment. If the horror
of a void be the caufe, fays he, the water muft rife to any
height however great; but if it be owing to the preffure
of the air, it will only rife till the w’eight of the water
in the pipe is in equilibrio with the preffure of the air,
according to the common laws of hydroftatics. And
he adds, that this is well known j for it is a fa ft, that
tionally
23
by the
weight of
the atmo-
fphere,
24
and pre-
di£led the
height to
which wa¬
ter would
rife in
thgm.
A T I C S. 669
pumps will not draw water much above forty palms, ak
though they may be made to propel it, or to lift it to
any height. He then makes an aflerlion, which, if true,
wail be deciftve. Let a very long pipe, ihut at one end,
be filled with water, and let it be erefted perpendicularly
with the clofe end uppermoft, and a Hopper in the other
end, and then its lower orifice immerfed into a veffel of
water •, the water will fublide in the pipe upon removing
the Hopper, till the remaining column is in equilibrio
with the preflure of the external air. This experiment
he propofes to the curious ; faying, however, that he
thought it unneceffary, their being already fuch abund¬
ant proofs of the air’s preffure.
It is probable that the cumberfomenefs of the necef- His predic-
fary apparatus protrafted the making of this experiment, t'011 ven-
Another equally concluftve, and much eaiier, was made ^
in 1642 after Galileo’s death, by his zealous and learned ^erimenti
difeip'le Toricelli. He filled a glafs tube, clofe at one end,
with mercury 5 judging, that if the fupport of the water
wras owing to the preffure of the air, and w7as the mea¬
fure of this preffure, mercury would in like manner be
fupported by it, and this at a height which was alfo the
meafure of the air’s preffure, and therefore 13 times lefs
than water. He had the pleafure of feeing his expec¬
tation verified in the completed: manner •, the mercury
defeending in the tube AB (fig. 5.), and finally fettling Fig.5.
at the height yB of 29!- Roman inches : and he found,
that when the tube w7as inclined, the point f wras in the
fame horizontal plane wdth f \\\ the upright tube, accord¬
ing to the received laws of hydroftatical preffure. The
experiment was often repeated, and foon became famous,
exciting great controverlies among the philofophers about
the poftibility of a vacuum. About three years afterwards
the fame experiment was publilhed, at Warfaw in Poland,
by Valerianus Magnus, as his owm fuggeftion and difeo-
very : but it appears plain from the letters of Roberval,
not only that Toricelli w7as prior, and that his experiment
wras the general topic of dilcuflion among the curious 5
but alfo highly probable that Valerianus Magnus was in¬
formed of it when at Rome, and daily converfant wdth
thofe who had feen it. He denies, however, even hav¬
ing heard of the name of Toricelli.
This was the era of philofophical ardour, j and we
think that it was Galileo’s invention and immediate ap¬
plication of the telefcope which gave it vigour. Dif-
coveries of the moft wonderful kind in the heavens, and
which required no extent of previous knowledge to un-
derftandthem, were thus put into the hands of every perfon
who could purchafe a fpy-glafs ; while the high degree
of credibility which fome of the dilcoveries, fuch as the
phafes of Venus and the rotation ^nd fatellites of Jupi¬
ter, gave to the Copernican lyftem, immediately fet the
whole body of the learned in motion. Galileo joined to
his ardour a great extent of learning, particularly of ma-,
thematical knowledge and found logic, and was even the
firft who formally united mathematics with phyfics; and
his treatife on accelerated motionwas the firft, and a pre-,
cious fruit of this union. About the years 1642 and 1644, . ?5
we find clubs of gentlemen affociated in Oxford and Lorn ^
don for the cultivation of knowledge by experiment j and Society^
before 1655 all the doftrines of hydroftatics and pneuma- Stc.
tics were familiar there, eftablilhed upon experiment. Mr
Boyle procured a coalition and correfpondence of thefe
clubs under the name of the Invifible and Philofophical
Society. In May. 1658 Mr Hooke finilhed for Mr
Boyle
\
670
PNEUMATICS.
27
fufed.
Boyle an air-pump, wliicli iiaJ employed him a long
ot'the air ^me> anc^ occafioned him feveral journeys to London for
pump. things which the workmen of Oxford could not execute.
He fpeaks of this as a great improvement on Mr Boyle’s
own pump, w’hich he had been uling fome time before.
Boyle therefore muft have invented his air-pump, and
was not indebted for it to Schottus’s account of Otto
Guerick’s, publifhed in his (Schottus) Mechanicci Hy-
draulo-pneumatica in 1637, as he afferts ("Techna Curiofa).
The Royal Society of London arofe in 16j6 from the
coalition of thefe clubs, after 15 years co-operation and
eorrefpondence. The Montmorine Society at Paris had
fubfifted nearly about the fame time 5 for we find Pafchal
in 1648 fpeaking of the meetings in the Sorbonne Col¬
lege, from which we know that fociety originated.—
Nuremberg, in Germany, was alfo a difHnguiihed femi-
nary of experimental philofophy. The magiftrates, fen-
fible of its valuable influence in many manufaftures, the
fource of the opulence and profperity of their city, and
many of them philofophers, gave philofophy a profeffed
and munificent patronage, furnifiling the philofophers
with a copious apparatus, a place of affembly, and a fund
for the expence of their experiments ; fo that this was
the firlf academy of fciences out of Italy under the pa¬
tronage of government. In Italy, indeed, there had
2§ long exified inftitutions of this kind. Rome was the cen-
The expe- tre of church-government, and the refort of all expedfi-
riments of ants for preferment. The clergy was the majority of the
TorirenianC^earne<^ Chriftian nations, and particularly of the
rapidly dif- fyftematic philofophers. Each, eager to recommend
r r 1 himfelf to notice, brought forward every thing that was
curious; and they were the willing vehicles of philofo-
phical communication. Thus the experiments of Gali¬
leo and Toricelli were rapidly diffufed by perfonsof rank,
the dignitaries of the church, or by the monks their ob-
fequious fervants. Perhaps the recent defedfiion of Eng¬
land, and the want of a refiding embafly at Rome, made
her fometimes late in receiving or fpreading philofophi-
cal refearches, and was the caufe that more was done
there propria Marte.
We hope to be excufed for this digreflion, We were
naturally led into it by the pretenfions of Valerianus
The merit Magnus to originality in the experiment of the mercury
•f Toricel- fupported by the preflure of the air. Such is the
b'S Ctlf rs^ ftre"Sth nati°nal attachment, that there were not
^ wanting fome who found that Toricelli had borrowed
his experiment from Honoratus Fabri, wflro had pro-
pofed and explained it in 1641 but whoever knows
the writings of Toricelli, and Galileo’s high opinion of
him, will never think that he could need fuch helps.
(See this furmife of Mounier in Schott. Tech. Cur. III.
at the end).
Galileo muft be confidered as the author of the expe¬
riment when he propofes it to be made. Valerianus
Magnus owns himfelf indebted to him for the principle
and the contrivance of the experiment. It is neither
wonderful that many ingenious men, of one opinion,
and inftrudled by Galileo, (hould feparately hit on fo
obvious a thing*, nor that Toiflcelli, his immediate dif-
ciple, his enthufiaftic admirer, and who was in the ha¬
bits of correfponding with him till his death in 1642,
{hould be the firfl: to put it in pra£lice. It became
the fubiefl: of difpute from the national arrogance and
felf-conceit of fome Frenchmen, who have always fhown
themfelves difpofed to confider their nation as at the
29
head of the republic of letters, and cannot brook the
concurrence of any foreigners. Roberval was in this
inltance, however, the champion of Toricelli ; but thofe
who know his controverfies with the mathematicians of
France at this time will eaiily account for this exception.
All now agree in giving Toricelli the honour of the unjuitly.
firjl invention ; and it univerfally paffes by the name of
the Toricellian Experiment. The tube is called
the Toricellian Tube j and the fpace left by the
mercury is called the Toricellian Vacuum, to di-
ftinguifir it from the Boylean Vacuum, which is only
an extreme rarefaftion. 31
The experiment was repeated in various forms, and R was I|e'*
with apparatus which enabled philufophers to examine Pea.tec^
feveral effe&s which the vacuum produced on bodies ex-forms#
pofed in it. This was done by making the upper part of
the tube terminate in a veffel of fome capacity, or com¬
municate with fuch a veflel, in which were included
along with the mercury bodies on wdiich the experiments
wTere to be made. When the mercury had run out, the
phenomena of thefe bodies were carefully obferved.
An objeblion was made to the conclufion drawn from An objec-
Toricelli’s experiment, which appears formidable. If the bon to the
Toricellian tube be fufpended on the arm of a balance, it C]°nC^U^Q;n
is found that the counterpoife mull be equal to the weight |t 0^YiatC(k
both of the tube and of the mercury it contains. This
could not be, fay the objedlors, if the mercury were fup¬
ported by the air. It is evidently fupported by the ba¬
lance ; and this gave rife to another notion of the caufe
different from the peripatetic fuga vacui; a fufpenfive
force, or rather attradlion, was afiigned to the upper part
of the tube.
But the true explanation of the phenomenon is moll
eafy and fatisfaftory. Suppofe the mercury in the ciftern
and tube to freeze, but without adhering to the tube, fo
that the tube could be freely drawn up and down. In
this cafe the mercury is fupported by the bafe, without
any dependence on the preffure of the air ; and the tube
is in the fame condition as before, and the-folid mercury
performs the office of a pifton to this kind of fyringe.
Suppofe the tube thruft down till the top of it touches
the top of the mercury. It is evident that it muft be
drawn up in oppofition to the preffure of the external
air, and it is precifely fimilar to the fyringe mentioned
in N° 16. The weight fuftained therefore by this arm '
of the balance is the weight of the tube and the down¬
ward preiTure of the atmofphere on its top. 33
The curiofity of philofophers being thus excited by Galileo’s
this very manageable experiment, it was natural now toon§inal ex'*
try the original experiment propofed by Galileo. -Ac-pprfbniied.
cordingly Berti in Italy, Pafchal in France, and many
others in different places, made the experiment with a
tube filled with water, wine, oil, Stc. and all with the
fuccefs which might be expefted in fo Ample a matter:
and lienee the doftrine of the weight and preffure of the
air was eftabliflred beyond contradiction or doubt. All
this was done before the year 1648.—A very beautiful
experiment was exhibited by Auzout, which completely
fatisfied all who had any remaining doubts. 34
A fmall box or phial EFGFI (fig. 6.) had two glafs An expert.
tubes, AB, CD, three feet long, inferted into it in fuchmentby
a manner as to be firmly fixed in one end, and to reach Auzout
nearly to the other end. AB was open at both ends, Dg. 6. 4
and CD was clofe at D. This apparatus was complete¬
ly filled with mercury, by unfcrewing the tube AB, fil-
ling
PNEUMATICS. 671
ling the box, and the tube CD; then fcrevving in the
tube AB, and filling it : then holding a finger on the
orifice A, the whole was inverted and fet upright in
the pofition reprefen ted in figure /3, immerfing the ori¬
fice A (now a of fig. /3.) in a (mall veffel of quickfilver.
The refult was, that the mercury ran out at the orifice a,
till its furface m n within the phial defcended to the top
of the tube b a. The mercury alfo began to defcend
in the tube dc formerly DC) and run over into the
tube b a, and run out at <7, till the mercury vn dc was
very near equal in a level with m n. The mercury de •
fcending in b a till it flood at k, 29 t inches above the
.furface o/> of the mercury in the ciftern, juft as in the
Toricellian tube.
The rationale of this experiment is very eafy. The
whole apparatus may firft be confidered as a Toricellian
tube of an uncommon fhape, and the mercury would
flow out at a. But as foon as a drop of mercury comes
out, leaving a fpace above m n, there is nothing to keep
up the mercury in the tube dc. Its mercury therefore
defcends alfo ; and running over into b a, continues to
fupply its expence till the tube d c almoft empty, or
can no longer fupply the wafle of b a. The inner fur¬
face therefore falls as low as it can, till it is level with
b. No more mercury can enter b a, yet its column
is too heavy to be fupported by the prelfure of the air
on the mercury in the ciftern below •, it therefore de¬
fcends in b a, and finally fettles at the height h 0, equal
to that of the mercury in the Toricellian tube,
decifive of The prettieft circumftance of the experiment remains,
the quef- Make a fmall hole g in the upper cap of the box. The
tion. external air immediately rufhes in by its weight, and now
prefles on the mercury in the box. This immediately raifes
the mercury in the tube dc to 29^ inches above m n.
It preffes on the mercury at k in the tube b a, balancing
the preflure of the air in the ciftern. The mercury in
the tube therefore is left to the influence of its own
weight, and it defcends to the bottom. Nothing can
3<; be more appofite or decifive.
The gravi- And thus the doctrine of the gravity and preflure of
ty of the the air is eftablifhed by the moft unexceptionable evi-
forearta" <*ence : anc* we are to aflume it as a ftatical
ticalprin- PrinciPle> and to affirm a priori all its legitimate confe-
ciple from quences.
which we And in the firft place, we obtain an exaft meafure of
*btain the preffure of the atmofphere. It is precifely equal to
the weight of the column of mercury, of tvater, of oil,
&c. which it can fupport 5 and the Toricellian tube, or
others fitted up upon the fame principle, are juftly term¬
ed barofcopes and barometers with refpeft to the air.
Now it is obferved that nrater is fupported at the height
37 of 3 2 feet nearly : The weight of the column is exaftly
meafure of 2000 ^ohdupois pounds on every fquare foot of bafe,
the preffureor 13to on every fquare inch. The fame conclufion
of the at- very nearly may be drawn from the column of mercury,
mofphere. which is nearly 29^ inches high when in equilibrium
with the preflure of the air. We may here obferve, that
the meafure taken from the height of a column of water,
wine, fpirits, and the other fluids of confiderable volati¬
lity, as chemifts term it, is not fo exaft as that taken
from mercury, oil, and the like. For it is obferved,
that the volatile fluids are converted by the ordinary
heat of our climates into vapour when the confining
preffure of the air is removed j and this vapour, by its
elafiicity, exerts a ftnall preffure on the furface of the
water, &c. in the pipe, and thus counteracts a fmall
part of the external preffure j and therefore the column
fupported by the remaining preffure muft be lighter,
that is, ftiorter. Thus it is found, that rectified fpirits
wdll not ftand much higher than is competent to a weight
of 13 pounds on an inch, the elafticity of its vapour ba¬
lancing about tV of the preffure of the air. We lhall
afterwards have occafion to confider this matter more
particularly.
As the medium height of the mercury in the barome¬
ter is 29* inches, we lee that the whole globe fuftains a
preffure equal to the whole weight of a body of mercury
of this height j and that all bodies on its furface fuftain
a part of this in proportion to their furfaces. An ordi¬
nary fixed man fuftains a preffure of feveral thoufand
pounds. How comes it then that we are not fenfible of 38
a preffure which one ftiould think enough to cruih us ^ difficulty
together ? This has been confidered as a ftrong objection lolvec*‘
to the preffure of the air j for when a man is plunged a
few feet under water, he is very fenfible of the preffure.
The anfwer is by no means fo eafy as is commonly ima¬
gined. We feel very diftinclly the effects of removing
this preffure from any part of the body. If any one will
apply the open end of a fyringe to his hand, and then
draw up the pifton, he will find his hand fucked into
the fyringe with great force, and it will give pain $ and
the foft part of the hand will fwell into it, being prefl'ed
in by the neighbouring parts, which are fubjeCt to the
aClion of the external air. If one lays his hand on the
top of a long perpendicular pipe, fuch as a pump filled
to the brim with water, which is at firft prevented from
running out by the valve below \ and if the valve be
then opened, fo that the water defcends, he will then
find his hand fo hard preffed to the top of the pipe that
he cannot drawr it ar^ay. But why do we only feel the
inequality of preffure ? There is a fimilar inftance where¬
in we do not feel it, although we cannot doubt of its
exiftence. When a man goes fkuvly to a great depth
under water in a diving-bell, we know unqueftionably
that he is expofed to a new and very great preffure, yet
he does not feel it. But thofe fails are not fufficiently
familiar for general argument. The human body is a
bundle of folids, hard or foft, filled or mixed with fluids,
and there are few or no parts of it which are empty.
All communicate either by veffels or pores j and the whole
furface is a fieve through which the infenfible perfpira-
tion is performed. The whole extended furface of the
lungs is open to the preffure of the atmofphere 5 every
thing is therefore in equilibrio : and if free or fpeedy ac~
cefs be given to every part, the body will not be dama¬
ged by the preffure, however great, any more than a
wet fponge would be deranged by plunging it any depth
in water. The preffure is inftantaneuufly diffufed by
means of the inc*>mpreffible fluids with which the parts
are filled ; and if any parts are filled with air or other
compreflible fluids, thefe are conipreffed till their elafti¬
city again balances the preffure. Befides, all our fluids -
are acquired flowly, and gradually mixed with that pro¬
portion of air which they can diffolve or contain. The
whole animal has grown up in this manner from the firft
vital atom of the embryo. For fuch reafons the preffure
can occafion no change of ftiape by fqueezing together
the flexible parts j nor any obftruftion by comprefiing
the veffels or pores. We cannot fay what wrould be felt
by a man, were it pofiible that he could have been pro¬
duced l
PNEUMATICS.
_ 39
The wea-’
ther-glafs.
40
The pref-
fure of the
air in pro¬
portion to
the eleva-
Aion
41
firftlup-
pofed by
Defcartes
and Paf-
chal, and
proved by
experi¬
ments.
duced and grown up in vacuo, and then fubjefted to the
compreflion. We even know that any hidden and con-
fiderable change of general preffure is very feverely felt.
Perfons in a diving-bell have been almoft killed by let¬
ting them down or drawing them up too fuddenly. In
drawing up, the elaftic matters within have fuddenly
fwelled, and not finding an immediate efcape have burft
the veffels. Dr Halley experienced this, the blood gufh-
ing out from his ears by the expanfion of air contained
in the internal cavities of this organ, from which there
are but very (lender paifages.
A very important obfervation recurs here: the pref¬
fure of the atmofphere is variable. This was obferved
almoft as loon as philofophers began to attend to the ba¬
rometer. Pafchal obferved it in France, and Defcartes
obferved it in Sweden in 1650. Mr Boyle and others
obferved it in England in i6<;6. And before this, ob-
fervers, who took notice of the concomitancy of thefe
changes of aerial preffure with the (fate of the atmo¬
fphere, remarked, that it was generally greateft in win¬
ter and in the night ; and certainly moft variable during
winter and in the northern regions. Familiar now with
the weight of the air, and confidering it as the vehicle
of the clouds and vapours, they noted with care the
connedtion between the weather and the preffure of the
air, and found that a great preffure of the air was gene¬
rally accompanied with fair weather, and a diminution
of it with rain and mifts. Hence the barometer came
to be conftdered as an index not only of the prefent date
of the air’s weight, but alfo as indicating by its varia¬
tions changes of weather. It became a Weather-
ceass, and continued to be anxiouily obferved with this
view. This is an important fubjedl, and in another place
is treated in fome detail.
In the next place, we may conclude that the preffure
of the air will be different in different places, according
to their elevation above the furface of the ocean : for if
air be an heavy fluid, it muft prefs in fome proportion
according to its perpendicular height. If it be a homo¬
geneous ffuid of equal denfity and weight in all its parts,
the mercury in the ciftern of a barometer muft be preffed
precifely in proportion to the depth to which that ciftern
is immerfed in it *, and as this preffure is exaftly mea-
fured by the height of the mercury in the tube, the
height of the mercury in the Toricellian tube muft be
exactly proportional to the depth of the place of obfer¬
vation under the furface of the atmofphere.
The celebrated Defcartes firft entertained this thought
(Epift. 67. of Pr. III.), and foon after him Pafchal.
His occupation in Paris not permitting him to try, the
juftnefs of his conjecture, he requefted Mr Perrier a
gentleman of Clermont in Auvergne, to make the ex¬
periment, by obferving the height of the mercury at
one and the fame time at Clermont and on the top of
a very high mouniain in the neighbourhood. His let¬
ters to Mr Perrier in 1647 are (bill extant. Accord¬
ingly Mr Perrier, in September 1648, filled two equal
tubes with mercury, and obferved the heights of both
to be the fame, viz. 26^3- inches, in the garden of the
convent of the Friars Minims, fituated in the loweft part
of Clermont. Leaving one of them there, and one of
the fathers to obferve it, he took the other to the top
of Puy de Domme, which was elevated nearly 500
French fathoms above the garden. He found its height
to be 23-/2 inches. On his return to the town, in a
place called Font de I'Arbre, 150 fathoms above the
garden, he found it 25 inches •, when he returned to the
garden it was again 26,j/, and the perfon fet to watch
the tube which had been left faid that it had not varied
the whole day. Thus a difference of elevation of 3000
French feet had occafioned a depreffion of 3 g inches j
from which it may be concluded, that 3^- inches of
mercury weighs as much as 3000 feet of air, and one-
tenth of an inch of mercury as much as 96 feet of air.
The next day he found, that taking the tube to the top
of a fteeple I 20 feet high made a fall of one-fixth of au *
inch. This gives 72 feet of air for one-tenth of an inch
of mercury j but ill agreeing with the former experiment.
But it is to be obferved, that a very fmall error of ob¬
fervation of the barometer w'ould correfpond to a great
difference of elevation, and alfo that the height of the
mountain had not been meafured w'ith any precifion.
This has been fincedone (Mem. Acad. par. 1703), and
found to be 529 French toifes.
Pafchal publilhed an account of this great experiment which
(Grande Exp. fur la Pefauteur de I'Airf and it was were re-
quickly repeated in many places of the world. In 1693 ot/ers^ ^
it was repeated in England by Dr Power (Powder’s Ex-
per. Phil.) ; and in Scotland, in 1661, by Mr Sinclair
profeffor of philofophy in the univerfily of Glafgow, who
obferved the barometer at Lanark, on the top of Mount
Tinto in Clydfdale, and on the top of Arthur’s Seat
at Edinburgh. He found a depreflion of two inches be¬
tween Glafgow and the top of Tinto, three quarters
of an inch between the bottom and top of Arthur’s
Seat, and q/ of an inch at the cathedral of Glafgow on
a height of 126 feet. See Sinclair’s Ars Nova et Mag¬
na Gravitatis et Leviiatis; Sturmii Collegium Experi-
mentale, and Schotti Technica Curiofa. 43
Hence we may derive a method of meafuring the Hence a
heights of mountains. Having afcertained with great
precifion the elevation correfponding to a fall of one- heights^
tenth of an inch of mercury, w'hich is nearly 90 feet,
we have only to obferve the length of the mercurial co¬
lumn at the top and bottom of the mountain, and to
allow 90 feet for every tenth of an inch. Accordingly
this method has been praftifed wTith great fuccefs: but
it requires an attention to many things not yet confi-
dered ; fuch as the change of denfity of the mercury
by heat and cold *, the changes of denfity of air, which
are much more remarkable from the fame caufes ; and
above all, the changes of the denfity of air from its
compreflibility •, a change immediately connected wdth
or dependent on the very elevation wre with to meafum
Of all thefe afterwards.
Thefe obfervations give us the moft accurate meafure A]f0 a
of the denfity of air and its fpecific gravity. This is meafure ef
but vaguely though direftly mealured by weighing air the denfity
in a bladder or vcffel. The weight of a manageable01 tne air*
quantity is fo fmall, that a balance fufficiently ticklifti to
indicate even very fenfible fraftions of it is overloaded
by the weight of the veffel which contains it, and ceafes
to be exaft : and when we take Bernouilli’s ingenious
method of fufpending it in water, we expofe ourfelves
to great rifle of error by the variation of the water’s
denfity. Alfo it muft neceffarily be humid air which
we can examine in this way : but the proportion of an
elevation in the atmofphere to the depreflion of the co¬
lumn of mercury or other fluid, by which we meafure
its preffure, gives us at once the proportion of this
weight
P N E U M
weight or tlieir fpecifie gravity. Thus fince it is found
that in fuch a date of preffure the barometer ftands at
30 inches, and the thermometer at 32°, 87 feet of rife
produces one-tenth of an inch of fall in the barometer,
the air and the mercury being both of the freezing tem¬
perature, we muft conclude that mercury is 10,44® times
heavier or denfer than air. Then, by comparing mer¬
cury and water, we get -g-§T nearly for the denfity or
air relative to water : but this varies fo much by heat
and moifture, that it is ufelefs to retain any thing more
than a general notion of it ; nor is it eafy to determine
whether this method or that by a&ual weighing be pre¬
ferable. It is extremely difficult to obferve the height
of the mercery in the barometer nearer than an
inch; and this will produce a difference of even five feet,
or of the whole. Perhaps this is a greater propor¬
tion than the error in weighing.
45 From the fame experiments we alfo derive fome know-
and fon\eoe ledge of the height of the aerial covering which furrounds
of theC our globe. When we raife our barometer 87 feet above
height of the furface of the fea, the mercury falls about one-tenth
the atmo- cf an inch in the barometer : therefore if the barome-
fphere. ter q10WS inches at the fea-fhore, we may expeft that,
by railing it 300 times 87 feet or 5 miles, the mercury
in the tube will defcend to the level of the ciftern, and
that this is the height of our atmofphere. But other
appearances lead us to fuppofe a much greater height.
Meteors are feen with us much higher than this, and
which yet give undoubted indication of being fupported
by our air. There can be little doubt, too, that the vi-
fibility of the expanfe above us is owing to the refiec-
tion of the fun’s light by our air. Were the heavenly
fpaces perfectly tranfparent, we ffiould no more fee them
than the pureft water through which we fee other oh-
jedls •, and we fee them as we fee water tinged with milk
or other faeculae. Now it is eafy to fhow, that the light
which gives us what is called twilight muff be refledled
from the height of at leaft 50 miles •, for we have it when
the fun is depreffed 18 degrees below our horizon.
Wh>4this -A- httle attention to the conftitution of our air will
knowledge convince us, that the atmofphere muft extend to a much
is not aci greater height than 300 times 87 feet. We fee from
curate. t]le mofl. familiar that it is compreffible 5 we can
fqueeze it in an ox-bladder. It is alfo heavy ; preffing
on the air in this bladder with a very great force, not
lefs than 1500 pounds. We muff therefore confider it
as in a ftate of compreffion, exifting in fmaller room than
it would affume if it were not compreffed by the incum¬
bent air. It muft therefore be in a condition fomething
refembling that of a quantity of fine carded wool thrown
loofely into a deep pit; the lower ftrata carrying the
weight of the upper ftrata, and being compreffed by them;
and fo much the more compreffed as they are further
down, and only the upper ftratum in its unconftrained
and moft expanded ftate. If we {hall fuppofe this wool
thrown in by a hundred weight at a time, it will be di¬
vided into ftrata of equal weights, but of unequal thick-
nefs ; the loweft being the thinned, and the fuperior
ftrata gradually increafing in thicknefs. Now, fuppofe
the pit filled with air, and reaching to the top of the
atmofpheve, the weights of all the ftrata above any ho¬
rizontal plane in it is meafured by the height of the mer¬
cury in the Toricellian tube placed in that plane ; and
one tenth of an inch of mercury is juft equal to the
weight of the loweft ftratum 87 feet thick : for on
Vol. XVI. Part II.
A T I C S. ’673
railing the tube 87 feet from the fea, the furface 6f the
mercury will defcend one-tenth of an inch. Flaife the
tube till the mercury fall another tenth : This ftratum
muft be more than 87 feet thick; how much more we
cannot tell, being ignorant of the law of the air’s ex-
panfion. In order to make it fall a third tenth, u'e
muft raife it through a ftratum ftill thicker; and fo ou
continually.
All this is abundantly confirmed by the very firft ex¬
periment made by the order and direftions of Pafchal :
For by carrying the tube from the garden of the con¬
vent to a place 150 fathoms higher, the mercury fell 1-fl¬
inches, or 1.2916; which gives about 69 feet 8 inches
of aerial ftratum for of an inch of mercury ; and by
carrying it fi'om thence to a place 350 fathoms higher,
the mercury fell or 1.9167 inches, which gives
109 feet 7 inches for -fg- of an inch of mercury. Thefe
experiments were not accurately made ; for at that time
the philofophers, though zealous, were but fcho'ars in
the fcience of experimenting, and novices ih the art. But
the refults abundantly fhow this general truth, and they
are completely confirmed by thoufands of fubfequent ob-
fervations. It is evident from the wdiole tenor of them,
that the ftrata of air decreafe in denfi y as wre afcend
through the atmofphere; but it remained to be difco-
vered wdiat is the force of this decreafe, that is, the
law of the air’s expanfion. Till this be done wTe can
fay nothing about the conftitution of our atmofphere :
we cannot tell in what manner it is fitteft for raifing
and fupporting the exhalations and vapours which are
continually arifing from the inhabited regions ; not as
an excrementitious w&fte, but to be lupported, perhaps
manufadlured, in that vaft laboratory of nature, and to
be returned to us in beneficent fliowfers. We cannot
ufe our knowledge for the curious, and frequently ufeful,
purpofe of meafuring the heights of mountains and taking
the levels of extenfive regions; in ftiort, without an ac¬
curate knowledge of this, wre can hardly acquire any
acquaintance with thofe mechanical properties which
diftinguifti air from thofe liquids wdiich circulate here
below.
Having therefore confidered at fome length the lead-
ing confequences of the air’s fluidity and gravity, let bilitv of the
us confider its compreffibility with the fame care ; and air.
then, combining the agency of both, we ffiall anfwer all
the purpofes of philofophy, difcover the law's, explain
the phenomena of nature, and improve art. We pro¬
ceed therefore to confider a little the phenomena which
indicate and chara&erile this other property of the air.
All fluids are elaftic and compreffible as well as air;
but in them the compreffibility makes no figure, or does
not intereft us while vre are confidering their preffures,
motions, and impulfions. But in air the comprefiibility
and expanfion draw7 our chief attention, and make it a
proper reprefentative of this clafs of fluids. „
Nothing is more familiar than the compreffibility of a familiar
air. It is feen in a bladder filled with it, which we can phenome-
forcibly fqueeze into lefs room ; it is feen in a fyringe,non* which
of which we can puffi the plug farther and farther as
~ we increafe the preffure. ^
But thefe appearances bryig into view another, and fhews its
the moft interefting, property of air, viz. its elaJHcity.elaiticity,
When we have Iqueezed the air in the bladder or fy-
ringe into lefs room, we find that the force with which
we comprejjed it is neceffary to leep it in this bulk ; and
4 Q. tW
674
5°
refilling
force, and
producing
motion.
51
Fluidity of
the air
52
experimen¬
tally
FiS- 7-
St
proved.
PNEUMATICS.
that if we ceafe to prefs it together, it will fwell out
and regain its natural dimenfions. This diftinguifhes
it effentially from fuch a body as a mafs of flour, fait,
or luch like, which remain in the compxefled ftate to
which wTe reduce them.
There is fomething therefore w'hich oppofes the com-
preflion different from the Ample impenetrability of the
air : there is fomething that oppofes mechanical force :
there is fomething too wdflch produces motion, not only
refilling comprefiion, burpufliing back the compreffmg
body, and communicating motion to it. As an arrow
is gradually accelerated by the bow firing prefling it
forward, and at the moment of its difcharge is brought
to a ftate of rapid motion ; fo the ball from a pop¬
gun or wind gun is gradually accelerated along the
barrel by the preffure of the air during its expanflon
from its compreffed ftate, and Anally quits it with an ac¬
cumulated velocity. Thefe tw'o motions are indications
perfectly Amilar of the elafticity of the bow and of the
air.
Thus it appears that air is heavy and elaftic. It
needs little conAderation to convince us in a vague man¬
ner that it is fluid. The eafe with which it is pene¬
trated, and driven about in every dire&ion, and the mo¬
tion of it in pipes and channels, however crooked and
intricate, entitle it to this charafter. But before wre
can proceed to deduce confequences from its fluidity,
and to offer them as a true account of what will happen
in thefe circumftances, it is neceffary to exhibit feme
diftindl and Ample cafe, in which the characleriflic me¬
chanical property of a fluid is clearly and unequivocally
obferved in it. That property of fluids from which all
the law's of hydroftatics and hydraulics are derived with
ftritfteft evidence is, that any preffure applied to any
part of them is propagated through the wdiole mafs in
every direftion ; and that in confequence of this diffu-
Aon of preffure, any twro external forces can be put in
equilibrio by the interpoAtion of a fluid, in the fame
way as they can be put in equilibrio by the intervention
of any mechanical engine.
Let a clofe veffel ABC (Ag. 7.), of any form, have
two upright pipes EDC, GFB, inferted into any parts
of its top, Aides, or bottom, and let water be poured
into them, fo as to ftand in equilibrio with the horizon¬
tal furfaces at E, D, G, F, and let D */, Ff, be hori¬
zontal lines, it will be found that the height of the co¬
lumn F d is fen Ably equal to that of the column Gf
This is a fail univerfally obferved in whatever way the
pipes are inferted.
Nowr the furface of the water at D is undoubtedly
preffed upwards with a force equal to a column of wa¬
ter, having its furface for its bafe, and E d for its height;
it is therefore prevented from riAng by fome oppoAte
force. This can be nothing but the elafticity of the
conflned air prefling it down. The very fame thing
muft be faid of the furface at F ; and thus there are
two external preffures at D and F fet in equilibrio by
the interpoAtion of air. The force exerted on the fur¬
face D, by the preffure of the column E d, is therefore
propagated to the furface at F ; and thus air has this
charadleriftic mark of fluidity.
In this experiment the weight of the air is infenflble
when the veffel is of fmall Aze, and has no fenAble fliare
in the preffure reaching at D and F. But if the ele¬
vation of the point F above D is very great, the column
E d will be obferved fenflbly to exceed the column G f
Thus if F be 70 feet higher than D, E d will be an inch
longer than the column Gf: for in this cafe there is
reading at D, not only the preffure propagated from F,
but alio the w'eight of a column of air, having the fur-
face at I) for its bafe and 70 feet high. This is equal
to the weight of a column of v'ater one inch high.
It is by this propagation of preffure, this fluidity,
that the pellet is difeharged from a child’s pop gun. It
flicks faft in the; muzzle ; and he forces in another pel¬
let at the other end, which he preffes fonvard with the
rammer, condenAng the air between them, and thus pro¬
pagating to the other pellet the preffure which he exerts,
till the fridion is overcome, and the pellet is difeharged.
by the air expanding and following it.
There is a pretty philofophical plaything which il-
luftrates this property of air in a very perfpicuous man¬
ner, and wThich we ftiall afterwards have occaAon to con-
Ader as converted into a moil ufeful hydraulic machine.
This is w'hat is ufually called Heroes fountain, having 54
been invented by a Syracufan of that name. It con-?ero's.
flits of two veffels KLMN (Ag. 8.), OPQB, which are ^l
clofe on all Ades. The tube AB, having a funnel a-top, a
paffes through the uppermoft veffel without communi¬
cating with it, being foldered into its top and bottom.
It alio paffes through the top of the under-veffel, where
it is alfo foldered, and reaches almoft to its bottom.
This tube is open at both ends. There is another open
tube ST, which is foldered into the top of the under
veffel and the bottom of the upper.veflel, and reach ^
almoft to its top. Thefe tw?o tubes ferve alfo to fup-
port the upper veffel. A third tube GF is foldered
into the top of the upper veffel, and reaches almoft to
its bottom. This tube is open at both ends, but the
orifice G is very fmall. Now fuppofe the uppermoft
veffel filled with water to the height EN, E e being its
furface a little below/ T. Stop the orifice G with the
finger, and pour in water at A. This will defeend
through AB, and comprefs the air in OPQR into lefs
room. Suppofe the w'ater in the under veflel to have
acquired the furface Cc, the air which formerly occupied
the whole of the fpaces OPQR, and KL e E will now
be contained in the fpaces 0 P c C and KL e E ; and its
elafticity will be in equilibrio with the w'eight of the
column of water, whofe bafe is the furface E e, and
whofe height is A c. As this preffure is exerted in
every part of the air, it will be exerted on the furface
E e of the W'ater of the upper veffel ; and if the pipe
FG wrere continued upwards, the water wmuld be Arp-
ported in it to an height e H above E e, equal to A c.
Therefore if the finger be now' taken from off the ori¬
fice G, the w'ater will fpout up to the fame height as if
it had been immediately forced out by a column of water
A c without the intervention of the air, that is, nearly
to H. If inftead of the funnel at A, the veffel have
a brim VW which will caufe the water difeharged at G
to run down the pipe AB, this fountain will play till
all the w'ater in the upper veffel is expended. The ope¬
ration of this fecond fountain wall be better underftood
from fig. 9. which an intelligent reader will fee is per- pj
feftly equivalent to fig. 8. A very powerful engine for ^ *
raifing water upon this principle has long been employed
in the Hungarian mines; w'here the pipe AB is about
200 feet high, and the pipe FG about 120; and thfe
condenfation is made in the upper veffel, and communi¬
cated
PNEUMATICS.
cak'd to the lover, at the bottom of the mine, by a long
pipe. See WATER-JVorks.
Laws of ^Te ma7 now apply to air all the laws of hydroftatics
hydrofta- and hydraulics, in perfect confidence that their legiti-
tics appli- mate confequences will be obfervred in all its fituations.
cable to air. We [n future fubftitute, in place of any force aft-
ing on a furface of air, a column of water, mercury, or
any other tluid whofe weight is equal to this force :
and as we know diftindlly from theory what will be the
confequences of this hydroftatic preflure, we fliail de¬
termine a priori the phenomena in air 5 and in cafes
where theory does not enable us to fay with pfecifion
what is the eifedl of this preffure, experience informs
us in the cafe of water, and analogy enables us to tranf-
fer this to air. We (hall find this of great fervice in
tome cafes, which otherwife are almoft defperate in the
,.,5 prefent hate of our knowledge.
More re- From fuoh familiar and fimple obfervations and expe-
finedexpe- riments, the fluidity, the heavinefs, and elafticity, are
runents, difeovered of the fubftance with which we are furround-
UC 1 as ed, and which we call a:r. But to underhand tnefe pro¬
perties, and completely to explain their numerous and
important confequences, we muh call in the aid of more
refined obfervations and experiments, which even this
fcanty knowledge of them enables us to make 5 we
muh contrive fome methods of producing with preci-
lion any degree of condenfation. or rarefaction, of em¬
ploying or excluding the gravitating preffure of air, and
of modifying at pleafure the aftion of all its mechanical
properties.
* method Nothing can be more obvious than a method of com-
of compref- preffmg a quantity of air to any degree, fl ake a cy-
fing the air finder or prifmatic tube AB (fig. 10.) fimt at one end,
bypKe and fit it with a pifton or plug C, fo nicely that no air
accc-xxiv. can Pa^s by its fides. This will be beh done in a cy-
Fig. 10. lindric tube by a turned hopper, covered with oiled
leather, and fitted with a long handle CD. When this
is thruh down, the air which formerly occupied the
whole capacity of the tube is condenfed into lefs room.
The force neceffary to produce any degree of compref-
lion may be concluded from the weight neceffary for
puihing down the plug to any depth. But this inhru-
ment leaves us little opportunity of making intereiling
experiments on or in this condenfed air; and the force
required to make any degree of compretuon cannot be
meafured with much accuracy \ becaufe the pihon muh
be very clofe, and have great friftion, in order to be
fufficiently tight: And as the compreflion is increafed,
the leather is more fqueezed to the fide of the tube *,
and the proportion of the external force, which is em¬
ployed merely to overcome this variable and uncertain
fri&ion, cannot be afeertained with any tolerable pre-
cifion. To get rid of thefe imperfeflions, the following
addition may be made to the inhrument, which then be-
,.3 comes what is called the ccndenjing fyringe.-
the con- The end of the fyringe is perforated with a very
denfing fy- fmall hole ef; and being externally turned to a fmall
tinge with cylinder, a narrow flip of bladder, or of thin leather,
foaked in a mixture of oil and tallow, muff be tied over
the hole. Now let us fuppofe the pifton puftied down
to the bottom of the barrel to which it applies clofe ;
when it is drawn up to the top, it leaves a void behind,
and the weight of the external air preffes on the flip of
bladder, which therefore claps clofe to the brafs, and
thus performs the part of a valve, and keeps it clofe fo
that no air can enter. But the pifton having reached
the top of the barrel, a hole F in the fide of it is juft
below the pifton, and the air nifties through this hole
and fills the barrel. Now pufti the pifton down again,
it immediately paffes the hole F, and no air efcapes
through it; it therefore forces open the valve at f and
efcapes while the pifton moves to the bottom. . 5P
Now let E be any veffel, fuch as a glafs bottle, hav- or
ing its mouth fumifhed with a brafs cap firmly ce¬
mented to it, having a hollow ferew which fits a fobd
ferew p 0, turned on the cylindric nozzle of the fyringe.
Screw the fyringe into this cap, and it is evident that
the air forced out of the fyringe will be accumulated in
this veffel: for upon drawing up the pifton the valve
f always ftiuts by the elafticity or expanding force of the
air in E ; and on puftiing it down again, the valve will
open as foon as the pifton has got fo far down that the
air in the lower part of the barrel is more powerful than
the air already in the veffel. Thus at every ftroke an
additional barrelful of air will be lorced into the veffel
E ; and it will be found, that after every itroke the pi¬
fton muft be farther pufhed down before the valve will
open. It cannot open till the prefiure arifing from the
elafticity of the air condenfed in the barrel is fuperior to
the elafticity of the air condenfed in the vellel 5 that is,
till the condenfation of the firft, or its denfity, is foms~
what greater than that of the laft, in order to overcome
the draining of the valve on the hole and the flicking 00
cafioned by the clammy matter employed to make it air-
tight. r
Sometimes the fyringe Is conftruefted with a valve In A deferent
the pifton. This pifton, inftead of being of one piece
and folid, eonfifts of two pieces perforated. The upper fynngC.
part i k n ?n is connected with the rod or handle, and
has its lower part turned down to a fmall cylinder,
which is ferewed into the lower part k Ion; and has
a perforation g h going up in the axis, and terminating
in a hole h in one fide of the rod, a piece of oiled lea¬
ther is drained acrofs the hole g. When the pifton is
drawn up and a void left below it, the weight of the ex¬
ternal air forces it through the hole hg, opens the valve
g, and fills the barrel. Then, on puihing down the pi-
fion, the air being fqueezed into lefs room, preffes on the
valve g, fhuts it 5 and none efcaping through the pifton,
it is gradually condenfed as the pifton delcends till it
opens the valve f and is added to that already accumu¬
lated in the veffel E. 61
Having in this manner forced a quantity of air into Elafticity
the veffel E, we can make many experiments in it in l^e air
this ftate of condenfation. We are chiefly concerned af '^[den
prefent with the effeeft which this produces on its elafti-fatjon>
city. We fee this to be greatly increafed j for we find
more and more force required for introducing every fuc-
ceflive barrelful. When the fyringe is unferewed, we
fee the air rulh out with great violence, and every in¬
dication of great expanding force. If the fyringe be
connedled with the veffel E in the fame manner as the
fyringe in N° 17. viz. hy interpofing a ftopcock B be¬
tween them (fee fig. 3.), and if this ftopcock have a
pipe at its extremiiy, reaching near to the bottom of the
veffel, which is previoufly half filled with water, we can
•obferve diftimffly when the elafticity of the air in the fy¬
ringe exceeds that of the air in the receiver : for the pi¬
fton muft be puftied down a certain length before the
air from the fyringe bubbles up through the water, and
4 Q, 2
hyo
62
A method
of judging
of the con-
denfation,
&c.
*3
not per¬
fectly accu¬
rate.
P N E U M
tire piilon mini be farther dov,m at each fuccefllve ftroke
before this appearance is obferved. When the air has
thus been accumulated in the receiver, it preffes the
iides of it outward, and will burft it if not ftrong enough.
It alfo preifes on the furface of the water j and if we
»ow fhut the cxjck, unfcrew the fyringe, and open the
cock again, the air will force the water through the
pipe with great velocity, caufing it to rife in a beautiful
jet. When a metal-receiver is ufed, the condenlatiofi
may be pufhed to a great length, and the jet will then
rife to a great height } which gradually diminiflies as the
water is expended and room given to the air to expand
itfelf. See the figure.
We judge of the condenfation of air in the veffel E
by the number of ffrokes and the proportion of the
capacity of the fyringe to that of the veffel. Suppofe
the firft to be one-tenth of the laid j then we know,
that after 10 ftrokes the quantity of air in the veflel is
doubled, and therefore its denfity double, and fo on af¬
ter any number of drokes. Let the capacity of the fy¬
ringe (when the pidon is drawn to the top) be c, and
that of the vefiel be b, and the number of drokes be n,
the denfity of air in the velfel will be or
,+T'
Eut this is on the fuppofition that the pidon accu¬
rately fills the barrel, the bottom of the one applying
clofe to that of the other, and that no force is neceffary
for opening either of the valves : but the fird cannot
be infured, and the lad is very far from being true. In
the condru&ion now defcribed, it will require at lead
one twentieth part of the ordinary prelfure of the air to
open the pidon valve : therefore the air which gets in
will want at lead this proportion of its complete eladi-
city; and there is always a fimilar part of the eladici-
ty employed in opening the nozzle valve. The conden¬
fation therefore is never nearly equal to what is here de¬
termined.
It is accurately enough meafured by a gage fitted to
the indrument. A slats tube GH of a cylindric bore,
and clofe at the end, is fcrewed into the fide of the cap
on the mouth of the veflel E. A fmall drop of water
or mercury is taken into this tube by warming it a little
in the hand, which expands the contained air, fo that
when the open end is dipped into water, and the whole
allowed to cool, the water advances a little into the tube.
The tube is furniflied with a fcale divided into fmall
equal parts, numbered from the clofe end of the tube.
Since this tube communicates with the veflel, it is evi¬
dent that the condenfation will force the water along
the tube, a (fling like a pifton on the air beyond it, and
the air in the tube and veflel ivill always be of one den¬
fity. Suppofe the number at which the drop ftands
before the condenfation is made to be c, and that it
hands at d when the condenfation has attained the de¬
gree required, the denfity of the air in the remote end
of the gage, and confequently in the veffel, will be -•
. . d
A variation Sometimes there is ufed any bit of tube clofe at one
^111 end, having a drop of water in it, Amply laid into the
veffel E, and furnhhed or not with a fcale : but this
can only be ufed wit h glafs veffel s, and thefe are too
<4
A better
method.
A T I C S,
weak to refill the preffure arifing from great condenfa¬
tion. In fuch experiments metalline veffels are ufed,
fitted with a variety of apparatus for different experi¬
ments. Some of thefe will be occafionally mentioned
afterwards. ^
It mult be obferved in this place, that very great con-Syringes
denfations require great foice, and therefore fmall fy- I°r great
ringes. It is therefore convenient to have them of va_ c.on<Lni'a-
rious fizes, and to began with thofe of a larger diame-
ter, which operate more quickly ; and when the con-
denfation becomes fatiguing, to change the lyringe for a
fmaller.
For this reafon, and in general to make the conden- ^
fing apparatus more convenient, it is proper to have acock be-
ftop-cock interpofed between the fyringe and the veffel, tween the
or as it is ufually called the receiver. This confiits of a f>ringe aiJd
brafs pipe, which has a well-ground cock in its middle,recemr'
and has a hollow ferew at one end, which receives the
nozzle ferew of the fyringe, and a folid ferew at the
other end, which fits the lerew of the receiver. See
3* . 68
By thefe gages, or contrivances fimilar to them, we Inftances of
have been able to afeertain very great degrees of con-grfcat con¬
denfation in the courfe of fome experiments. Dr Hales c'en^at*on
found, that when dry wood was put into a ftrong veffel,prove
which it almoft filled, and the remainder was filled with
water, the fwelling of the wood, occafioned by its im¬
bibition of water, condenfed the air of his gage into the
thoufandth of its original bulk. He found that peafe
treated in the fame way generated elaftic air, which
prefling on the air in the gage condenfed it into the
fifteen hundredth part of its bulk. This is the greateft
condenfation that has been afeertained with precifion,
although in other experiments it has certainly been car¬
ried much farther j but the precife degree could not be
afeertained.
The only ufe to be made of this obfervation at pre- a;r ^
fent is, that fince we have been able to exhibit air in a water to be
denfity a thoufand times greater than the ordinary den- eflentially
fity of the air we breathe, it cannot, as fome imagine,^^erent>
be only a different form of water; for in this ftate it is
as denfe or denfer than water, and yet retains its great
expanfibility.
Another important obfervation is, that in every ftate and ibow
of denfity in which we find it, it retains its perfedt the error of
fluidity, tranfmitting all preffures which are applied tofo.me °Pi'
it with undiminifhed force, as appears by the equality
conflantly obferved between the oppofing columns ofelafticity,
water or other fluid by which it is compreffed, and by &c.
the facility with which all motions are performed in it
in the moft compreffed ftates in which we can make ob-
fervations of this kind. This fa<fl is totally incompa¬
tible with the opinion of thofe who aferibe the elaftici-
ty of air to the fpringy ramified ftrudlure of its particles,
touching e.ch other like fo many pieces of fponge or
foot-balls. A colledtion of fuch particles might indeed
be pervaded by folid bodies with confiderable eafe, if
they were merely touching each other, and not flibjed-
ed to any external preffure. But the moment fuch pref¬
fure is exerted, and the aflemblage fqueezed into a
fmaller fpace, each preffes on its adjoining particles:
they are individually compreffed, flattened in their touch¬
ing furfaces, and before the denfity is doubled they are
fqueezed into the form of perfed cubes, and compofe a
mafs,
71
Confequen-
ces of the
air’s elaf-
ticity.
7Z
Its great
expiinfibili
ty
73
proved by
experiment
Fig- II.
74
Attempts
to difcever
the limits
of this ex-
panfion by
75
a fyringe;
Fig. 12
P N E U M
tnafs, which may indeed propagate preffure from one
place to another in an imperfecl manner, and with great
diminution of its intenfity, but will no more be fluid than
a mafs of foft clay. It will be of ufe to keep this ob-
fervation in mind.
We have feen the air is heavy and compreflible, and
might now proceed to deduce in order the explanation
of the appearances confequent on each of thefe pro¬
perties. But, as has been already obferved, the elafti-
city of air modifies the efifeas of its gravity fo remark¬
ably, that they would be imperfeaiy underftood it both
qualities were hot combined in our confideration of ci¬
ther. At any rate, fome farther confequences of its elaf-
ticity Hiuft be confidered, before wre underftand the means
of varying at pleafure the effeas of its gravity. ^
Since air is heavy, the low'er ftrata of a mafs of air
. mull fupport the upper 5 and, being compreflibk, they
muft be condenfed by their weight. In this date of com-
preflion the elafticity of the lower ftrata of air aas m
oppofition to the weight of the incumbent air, and ba¬
lances it. There is no reafon which would make us fup-
pofe that its expanding force belongs to it only when in
fuch a ftate of compreflion. It is more probable, that,
if we could free it from this preffure, the air would ex¬
pand itfelf into ftill greater bulk. This is moft diftindt-
ly feen in the following experiment.
Into the cylindric jar ABCD (fig. n.) which has
a fmall hole in its bottom, and is furmftied with an
air-tight pifton E, put a fmall flaccid bladder, having its
mouth tied tight with a ftring. _ Having puftied the
pifton near to the bottom, and noticed the ftate of the
bladder, flop up the hole in the bottom of the jar with
the finger, and draw up the pifton, which will require a
confiderable force. You will obferve the bladder iwell
out, as if air had been blown into it j and it wdll again
collapfe on allowing the pifton to defcend. Nothing can
be more unexceptionable than the conclufion from this
experiment, that ordinary air is in a ftate of compreftion,
and that its elafticity is not limited to this ftate.. The
bladder being flaccid, (hows that the included air is in
the fame ftate with the air which furrounds it; and the
fame muft be affirmed of it while it fwells but ftill re¬
mains flaccid. We muft conclude, that the whole air
within the veffel expands, and continues to fill .it, when
its capacity has been enlarged. And .fince this is ob¬
ferved to go on as long as we give it more room, we
conclude, that by fuch experiments we have not yet
given it fo much room as it can occupy.
It was a natural objeft of cur'iofity to difcover the
limits of this expanfion ; to know what was the natural
unconftrained bulk of a quantity of an, Deyond which
it would not expand though all external comprefling
force were removed. Accordingly philofophers con-
ftrufted inftruments for rarefying the air. The common
water pump had been long familiar, and appeared very
proper for this purpofe. The moft obvious is the fol¬
lowing.
Let the barrel of the fyrmge AB (fig. 12.) commu¬
nicate with the veffel V, with a ftopcock C between
them. Let it commuinicate with the external air by
another orifice D, in any convenient fituation, alfo.fur-
niftied with a ftopcock. Let this fyringe have a pifton
very accurately fitted to it fo as to touch the bottom all
over when puftied down, and have no vacancy about
the Tides.
A T I C S. 677
Now, fuppofc the pifton at the bottom, the cock C 7^
open, and the cock D thut, draw the pifton to the^ J e
top. The air which filled the veffel V will expand fo Jwbich
as to fill both that veffel and the barrel AB ; and as no
reafon can be given to the contrary, we muft fuppofe
that the air will be uniformly diffufed through both.
Calling V and B the capacity of the veffel and barrel,
it is plain that the bulk of the air will now be V B j
and fince the quantity of matter remains the fame, and
the denlity of a fluid is as its quantity of matter directly
and its bulk inverfely, the dcnfity of the expanded air
will be —the denfity of common air being 1; for
V -J-B
V + B : \ = i :yq-g.  77
The pifton requires force to raife it, and it is raifed in we infer
oppofition to the preffure of the incumbent atmofphere ; the ditninu^
for this had formerly been balanced by the elafticity
of the common air: and we conclude from the ff expanded
that force is required to raife the piflot^ that the elaftici- air,
ty of the expanded air is lefs than that of air in its ordi¬
nary ftate ; and an accurate obfervation of the force ne-
ceffary to raife it would lhow how much the elafticity.is
diminilhed. When therefore the pifton is let go, it will
defcend as long as the preffure of the atmofphere exceeds
the elafticity of the air in the barrel j that is, till the air
in the barrel is in a ftate of ordinary denfity. To put
it further down will require force, becaufe the air muft:
be compreffed in the barrel *, but if we open the cock
D, the air will be expelled through it, and the pifton
will reach the bottom. 78
Now fhut the difcharging coch D, and open the cock and calcu-
C and draw up the pifton. The air which occupied late its den*
’ f * TT lltV.
V
the fpaceV, with the denfity y --^, will now occupy
fpace V-J-B, if it expands fo far. bo have its
denfity D, fay, As its prefent bulk V + B is to its
former bulk V, fo is its former denfity „ to its
new denfity 5 which will therefore be
V+B
V+V
V+BxV+B,
or
V+B
It is evident, that if the air continues to expand,
the denfity of the air in the veffel after the third draw-
V *
ing up of the pifton will be y—j- ’ after the fourth
—^ !4
, and after any number of ftrokes n
Thus, if the veffel is four times as
79
it will be
V+B
will be
V + B
large as the barrel, the denfity after the fifth ftroke
will be jtIx, nearly \ of its ordinary denfity.
On the other hand, the number n of ftrokes
neceffary for reducing air to the denfity D is
Log D  
Log V—Log (V+B)’
Thus we fee that this inftrument can never abftraft Some iu-
the whole air in confequence of its expanfion, but only
rarefy it continually as long as it continues to expand jjhis infliv:
nay, there is a limit beyond which the rarefaction can-meat.
not-
80
Sr
678
PNEUMATICS.
82
Remedied
by another,
FlS- l3-
Fig. 14.
§3
•called an
exhaujlmg
Syringe.
84
ats con-
ft radii on
-iind
IS'
85
*peration.
not go. \iVlien the pifton has reached the bottom,
there remains a fmall fpace between it and the cock
C filled with common air. When the pifton is drawn
up, this fmall quantity of air expands, and alfo a fimilar
quantity in the neck of the other cock } and no air
will come out of the receiver V till the expanded air
in the barrel is of a fmaller denfity than the air in the
receiver. This circumftance evidently direfts us to make
thefe two fpaces as fmall as poffible, or by fome contri¬
vance to fill them up altogether. Perhaps this may be
done effectually in the following manner.
Let BE (fig. 13.) reprefent the bottom of the bar¬
rel, and let the circle HKI be the feCtion of the key
• of the cock, of a large diameter, and place it as near
to the barrel as can be. Let this communicate with
the barrel by means of a hole FG widening upwards,
as the fruftum of a hollow obtufe cone. Let the bottom
of the piffon bfhg e be fhaped fo as to fit the bottom
of the barrel and this hole exaCtly. Let the cock be
pierced with two holes. One of them, HI, paffes,
perpendicularly through its axis, and forms the commu¬
nication between the receiver and barrel. The other
hole, KL, has one extremity K on the fame circum¬
ference with H, fo that when the key is turned a fourth
part round, K will come into the place of H : but this
hole is pierced obliquely into the key, and thus keeps
clear of the hole HI. It goes no further than the
axis, where it communicates with a hole bored along
the axis and terminating at its extremity. This hole
forms the communication with the external air, and
ferves for difcharging the air in the barrel. (A fide
view, of the key is feen in fig. 14.). Fig. 1 2. firows the
pofition of the cock while the pifton is moving upwards,
and fig. 14. (hows its pofition while the pifton is moving
downwards. When the pifton has reached the bottom,
the conical piece f h g ol the pifton, which may be of
firm leather, fills the hole FHG, and therefore com¬
pletely expels the air from the barrel. The canal KL /
of tire cock contains air of the common denfity 5 but
this is turned afide into the pofition KL (fig. 13.),
while the pifton is ftill touching the cock. It cannot
extend into the barrel during the afcentof the pifton. In
place of it the perforation HLI comes under the pifton,
filled with air that had been turned afide with it when
the pifton was at the top of the barrel, and therefore
oi the fame denfity with the air of the receiver. It ap¬
pears therefore that there is no limit to the rarefaction
as long as the air will expand.
This inftrument is called an Exhausting Syringe.
It is more generally made in another form, which is
much lefs expenfive, and more convenient in its ufe.
Inftead of being furnifhed with cochs for eftablilhing
the communications and (hutting them, as is necef-
fary, it has valves like thofe of the condenfing fyringe,
but opening in the oppofite direftion. It is thus made :
The pipe of communication or conduit MN (fig.
15.) has a male fcrew in its extremity, and over this is
tied a flip of bladder or leather M. The lower half of
the pifton has alfo a male fcrew on it, covered at the
end with a flip of bladder O. This is fcrewed into the
upper half of the pifton, which is pierced with a hole H
coming out of the fide of the rod.
Now fuppofe the fyringe fcrewod to the conducting
pipe, and that fcrewed into the receiver V, and the
pifton at the bottom of the barrel. When the pifton
is drawn up, the preffure of the external air (huts the
valve O, and avoid is left below the pifton : there is
therefore no preffure on the upper fide of the valve M
to balance the elafticity ot the air in the receiver which
formerly balanced the weight of the atmofphere. The
air therefore in the receiver lifts this valve, and diftri-
butes itfelf between the veffel and the barrel; fo that
when the pifton has reached the top the denfity of the
air in both receiver and barrel is as before ——1—
V-J-B
When the pifton is let go it defcends, becaule the 8¥
elafticity of the expanded air is not a balance for the
prellure of the atmofphere, which therefore preffes down
the pifton with the difference, keeping the pifton-valve
ihut all the while. At the fame time the valve M
al!o (huts : for it was opened by the prevailing elafticity
of the air in the receiver, and while it is open the two
airs have equal denfity and elafticity ; but the moment
the pifton defcends, the capacity of the barrel is dimi-
niftred, the elafticity of its air increafes by collapfing,
and now prevailing over that of the air in the receiver
(liiits the valve M.
When it has arrived at fuch a part of the barrel 87
that the air in it is of the denfity of the external air,
there is no force to pufli it farther dowm ; the hand’
muft therefore prefs it. This attempts to condenfe the
air in the barrel, and therefore increafes its elafticity j
fo that it lifts the valve O and efcapes, and the pifton
gets to the bottom. When drawn up again, greater
force is required than the laft time, becaufe the elafti-
city of the included air is lefs than in the former ftroke.
The pifton rifes further before the valve M is lifted up, and
when it has reached the top of the barrel the denfity of
. . . V I4
the included air is -- ^ v |. The piftcn, when let go,
wirl defcend further than it did before ere the pifton-
yalve open, and the preffure of the hand will again pulh
it to the bottom, all the air efcaping through G. The
rarefaction will go on at every fucceflive ftroke in the
fame manner as with the other fyringe. s|
. This fyringe is evidently more eafy in its ufe, requir-Advantages
mg no attendance to the cocks to open and (hut themfy fy~
at the proper times. On this account this conftruc-lin^over
tion of an exhaufting fyringe is much more generally
_ 89
.But it is greatly inferior to the fyringe with cockshs inieriori-
with refpeCt to its power of rarefaction. Its operation1?*
is greatly limited. It is evident that no air will come
out of the receiver unlefs its elafticity exceed that of the
air in the barrel by a difference able to lift up the valve
M. A piece of oiled leather tied acrofs this hole can
hardly be made tight and certain of clapping to the
hole without fome fmall draining, which muft therefore
be.overcome. It muft be very gentle indeed not to re¬
quire a force equal to the weight of two inches of water,
and this is equal to about the 200th part of the whole
elafticity of the ordinary a;r ; and therefore this fyringe,
for this reafon alone, cannot rarefy air above 200 times,
even though air were capable ef an indefinite expan-
fion. In like manner the -valve O cannot be railed
without a fimilar prevalence of the elafticity of the air
in the barrel above the weigh! of the atmofphere.
Thefe caufes united, make it difficult to rarefy the air
more than 100 times, and very few fuch fyringes will
- rarefy
90
The former
fynnge,
however,
more liable
to go out
of order.
9*
Invention
of the air-
pnmp by
Guericke.
92
Conftrue-
tion of his
pump.
Fig. 16.
P N E U M
rarefy it more than 50 times 5 whereas the fyringe with
cocks, when new and in good order, will rarefy it 1000
times.
But, on the other hand, fyringeswith cocks are much
more expenfive, efpeciaTly when furniihed with appara¬
tus for opening and {hutting the cocks. They are more
difficult to make equally tight, and (which is the great-
eii objection) do not remain long in good order. The
cocks, by lb frequently opening and (hutting, grow
Jsofe, and allow the air to efcape. No method has been
found of preventing tins. They muff be ground tight *
by means of emery or other cutting powders. Some of
thefe unavoidably flick in the metal, and continue to
wear it down. For this reafon philofophers, and the
makers of philofophical inftruments, have turned their
clxief attention to the improvement of the fyringe with
valves. We have been thus minute in the account of
the operation of rarefa&ion, that the reader may better
underhand the value of thefe improvements, and in
general the operation of the principal pneumatic en¬
gines.
Of the Air-Pump.
An Air-Pump is nothing but an exhaufting lyringe
accommodated to a variety of experiments. It was firft
invented by Otto Guericke, a gentleman of Magde-
burgh in Germany, about the year We truft
that it will not be unacceptable to our readers to fee this
inftrument, which now makes a principal article in a
philofophical apparatus, in its firft form, and to trace it
through its fucceflive fteps to its prefent ftate of improve¬
ment.
Guericke, indifferent about the folitary poffeffion of
an invention which gave entertainment to numbers who
came to fee his wonderful experiments, gave a minute
defcription of all his pneumatic apparatus to Gafpar
Schotlus profeffor of mathematics at Wirtemberg, who
immediately pubiifhed it with the author’s confent, with
an account of fome of its performances, firrt in 1657,
in his Mechanic a Hydraulico-pneumatica; and then in
his Technica Cur if a, in 1664, a curious colle&ion of all
the wonderful performances of art which he collefled by
a .correfpondence over all Europe.
Otto Guericke’s air-pump confifts of a glafs receiver
A (fig. 16.) of a form nearly fpherical, fitted up with
a brafs cap and cock B. The nozzle of the cap was
fixed to a fyringe CDE, alfo of brafs, bent at E> into
half a right angle. This had a valve at D, opening
from the receiver into the fyringe, and fhutting when
preffed in the oppofite dire&ion. In the upper fide of
the fyringe there is another valve F, opening from the
fyringe into the external air, and {hutting when preffed
inwards. The pifton had no valve. '1 he fyringe, the
cock B, and the joint of the tube, were immerfed in a
ciftern filled with water. From this defcription it is
eafy to underhand the operation of the inftrument.
When the pifton was drawn up from the bottom of the
fyringe, the valve F was kept fliut by the preffure of
the external air, and the valve D opened by the elafti-
city of the air in the receiver. When it was puflied
down again, the valve D immediately (hut by the fupe-
rior elafticity of the air in the fyringe ; and when this
was fufficiently compreffed, it opened the valve F, and
A T I C S. 679
was difcharged. It was immerfed'in water, that no-air Ak-pump
might find its way through the joints or cocks. ^
It would feem that this machine was not very perfe£l, Its impev-
for Guericke fays that it took feveral hours to produce fe&ions.
an evacuation of a moderate-hzed veil el $ but he fays,
that when it was in good order, the rarefa&ion (for he
acknowledges that it was not, nor could be, a complete
evacuation) was fo great, that when the cock was open¬
ed, and water admitted, it filled the receiver fo as fome-
times to leave no more than the bulk of a pea filled with
air. This is a little furprifing} for if the valve F be
placed as far from the bottom of the fyringe as in Schot-
tus’s figure, it would appear that the rarefaction, could
not be greater than what muft arife from the air in 1)1'
expanding till it filled the whole fyringe : becaufe as foon
as the pifton in its defcent paffes h it can ducharge no
more air, but muft cemprefs it between F and the bot¬
tom, to be expanded again when the pifton is drawn up.
It is probable that the pifton was- not very tight, but
that on prefling it down it allowed the air to pafs it $
and the wTater in which the whole was immerfed pre¬
vented the return of the air when it was drawn up
again : and this accounts for the great time neceffary for
producing the defired rarefaction. ^
Guericke, being a gentleman of fortune, fpared no H;s un_
expence, and added a part to the machine, which favedprovemsnt
his numerous vifitants the trouble of hours attendance it*
before they could fee the curious experiments with the
rarefied air. He made a large copper veffel G (fig. 17.), rig- 17*
having a pipe and cock below, which paffed through the
floor of the chamber into an under apartment, where it
was joined to the fyringe immerfed in the ciftern of wa¬
ter, and worked by a lever. The upper par t of the vef¬
fel terminated in a pipe, furniflied with a flopcock H,
furrounded with a fmall brim to hold water for prevent¬
ing the ingrefs of air. On the top was another cap I,
•alfo filled with water, to proteft the jun&ion of the
pipes with the receiver K. This great veffel was always
kept exhaufted, and workmen attended below. When
experiments were to be performed in the receiver K, it
was fet on the top of the great veffel, and the cock H
was opened. The air in K immediately diffufed itfelf
equally between the two veffels, and was fo much more
rarefied as the receiver K wras fmaller than the veffel G.
When this rarefaftion was not fufficient, the attendants
below immediately worked the pump.
Thefe particulars deferve to be recorded., as they {how
the inventive genius of this celebrated philofopher, and
becaufe they are ufeful even in the prefent advanced
ftate of the ftudy. Guericke’s method of excluding air
from all the joints of his apparatus, by immerfing thefe
joints in water, is the only method that has to this day-
been found effe&ual ; and there frequently occur expe¬
riments where this exclufion for a long time is abfolutely
neceffary. In fuch cafes it is neceffary to conftrudl little
cups or cifterns at every joint, and to fill them with wa¬
ter or oil. In a letter to Schottus, 1662-3, he defcribes
very ingenious contrivances for producing complete ra¬
refaction after the elafticity of the remaining air has
been fo far diminfthed that it is not able to open the
valves. He opens the exhaufting valves by a plug,
which is puflied in by the hand } and the difcharging
valve is opened by a fmall pump placed on its outfide, fo
that it opens into a void inftead of opening againfl: the
preffure
68 o
PNEUMATICS.
. 95
Merits of
■"Guericke.
96 c
I’ragrefs of
experimen¬
tal philofo-
.j)hy.
Air-pump, preffure of die atmofpliere. (See Schotti Technica Cu-
riofa, p. 68. 70.). Thefe contrivances have been lately
added to air-pumps by Haas and Hurter as new inven¬
tions.
It muft be acknowledged, that the application of the
pump or fyringe to the exhauition of air was a very ob¬
vious thought on the principle exhibited in N° 17. and
in this way it was alfo employed by Guericke, who firfi;
filled the receiver with water, and then applied the fy-
tinge. But this was by no means either his objedl or
his principle. His objeft was not folely to procure a
veffel void of air, but to exhauft the air which was al¬
ready in it 5 and his principle was the power which he
fufpe&ed to be in air of expanding itfelf into a greater
fpace when the force was removed which he fuppofed
to comprefs it. He exprefsly fays (” Traci, de F.xpcri-
mentis Maqdeburgicis, et in Epi/l. ad Schottum), that the
contrivance occurred to him accidentally when occupied
with experiments in the Toricellian tube, in which he
found that the air would really expand, and completely
fill a much larger fpace than what it ufually occupied,
and that he had found no limits to the expanfion, evin¬
cing this by fafts which we fhall perfectly underftand
by and by. This was a doftrine quite new, and re¬
quired a jphilofophical mind to view it in a, general and
fyftematic manner , and it muft be owned that his man¬
ner of treating the fubjeft is equally remarkable for in¬
genuity and for modefty. (Epi/i. ad Sc hot turn).
His doftrine and his machine were foon fpread over
Europe. It was the age of literary ardour and philofo-
phical curioftty ; and it is moft pleafant to us, who,
Handing on the fhoulders of our predeceffors, can fee far
around us, to obferve the eagernefs with which every
new, and to us frivolous, experiment was repeated and
canvafled. The worfhippers of Ariftotle were daily re¬
ceiving fevere mortifications from the experimenters, or
empirics as they affe&ed to call them, and they exerted
themfelves ftrenuoufly in fupport of his now tottering
caufe. This contributed to the rapid propagation of
every difeovery } and it was a moft profitable and re-
fpe&able bufinefs to go through the chief cities of
Germany and France exhibiting philofophical experi¬
ments.
About this time the foundations of the Royal Society
of London were laid. Mr Boyle, Mr Wren, Lord
Brounker, Dr Wallis, and other curious gentlemen,
held meetings at Oxford, in which were received ac¬
counts of whatever was doing in the ftudy of nature 5
and many experiments were exhibited. The refearches
of Galileo, Toricelli, and Pafchal, concerning the pref¬
fure of the air, greatly engaged their attention, and
many additions were made to their difeoveries. Mr
Boyle, the moft ardent and fuccefsful ftudier of nature,
had the principal (hare in thefe improvements, his in-
quifitive mind being aided by an opulent fortune. In
a letter to his nephew Lord Dungarvon, he fays that
he had made many attempts to fee the appearances ex¬
hibited by bodies freed from the preffure of the air.
He had made Toricellian tubes, having a fmall veffel
a-top, into which he put fome bodies before filling the
tubes with mercury *, fo that when the tube was let
upright, and the mercury run out, the bodies were in
vacuo. Fie had alfo abftradfted the water from a veffel,
by a fmall pump, by means of its weight, in the man¬
ner deferibed in N° 17, having previoufly put bodies
4
97
Ardour of
JVIr Boyle.
Plate
ccccxxv.
Fie. 18.
into the veffel along with the water. But all thefe ways Air-pump,
were very troublefome and imperfeft. He was delight¬
ed when he learned from Schottus’s firft publication,
that Counlellor Guericke had effected this by the ex-
panfive power of the air $ and immediately fet about con-
ftrufting a machine from his own ideas, no defeription
of G uericke’s being then publilhed.
It confifted of a receiver A (fig. 18.), furnilhed with
a ftopcock B, and fyringe CD placed in a vertical pofi-
tion below the receiver. Its valve C was in its bottom,
clofe adjoining to the entry of the pipe of communica¬
tion 5 and the hole by which the air iffued was farther
fecured by a plug which could be removed. The pifton
was moved by a wheel and rackwork. The receiver of 98
Guericke’s pump was but ill adapted for any confider- His air-
able variety of experiments^ and accordingly very few
were made in it. Mr Boyle’s receiver had a large open¬
ing EF, with a ftrong glafs margin. To this was fitted
a ftrong brafs cap, pierced with a hole G in its middle,
to which was fitted a plug ground into it, and fhaped
like the key of a cock. The extremity of this key was
furniftied with a ferew, to which could be affixed a hook,
or a variety of pieces for fupporting what was to be exa¬
mined in the receiver, or for producing various motions
within it, without admitting the air. This was farther
guarded againft by means of oil poured round the key,
where it was retained by the hollow cup-like form of ihe
cover. With all thefe precautions, however, Mr Boyle
ingenuoufiy confeffes, that it was but feldom, and with
great difficulty, that he could produce an extreme de¬
gree of rarefaftion ; and it appears by Guericke’s letter
to Schottus, that in this refpeft the Magdeburgh ma¬
chine had the advantage. But moft of Boyle’s very in-
terefting experiments did not require this extreme rare-
fa£Hon *, and the variety of them, and their philofophic
importance, compenfated for this defeft, and foon eciip-
fed the fame of the inventor to fuch a degree, that the
ftate of air in the receiver was generally denominated
the vacuum Boyleanum, and the air-pump was called
machina Boyleana. It does not appear that Guericke
was at all folicitous to maintain his claim to priority of
invention. He appears to have been of a truly noble
and philofophical mind, aiming at nothing but the ad¬
vancement of fcience. 99
Mr Boyle found, that to make a veffel air-tight, it His comri*
was fufficient to place a piece of wet or oiled leather on vances to
its brim, and to lay a flat plate of metal upon this.
The preffure of the external air fqueezed the two folid
bodies fo hard together, that the foft leather effeftually
excluded it. This enabled him to render the whole ma¬
chine incomparably more convenient for a variety of ex¬
periments. He caufed the conduit-pipe to terminate in
a flat plate which he covered with leather, and on this
he fet the glafs ball or receiver, which had both its up¬
per and lower brim ground flat. He covered the upper
orifice in like manner with a piece of oiled leather and a
flat plate, having cocks and a variety of other perfora¬
tions and contrivances fuited to his purpofes. This he
found infinitely more expeditious, and alfo tighter, than
the clammy cements which he had formerly ufed for le-
curing the joints. joo
He was now afiifted by Dr Hooke, the moft ingeni- Dr Hooke's
ous and inventive mechanic that the world has ever feen. improve-
This perfon made a great improvement on the air-pump, ^yle^air-
by applying two fyringes whofe pifton-rods were worked pUmp.
by
PNEUMATICS.
681
TOI
Ce nerally
adopted.
roi
Jlawkef-
bee’s im-
pi'ovements,
lig. is>.
*03
Barrels.
by tbc fAme wheel) as m 20. and putting valves
in the piltons in the lame manner as in the pifton of
a common pump. This evidently doubled the expe¬
dition of the pump’s operation ; but it alfo greatly dimi-
niflied the labour of pumping : for it mult be obferved,
that the pifton H muft be drawn up againft the preffure
of the external air, and when the rarefa£tion is nearly
perfect this requires a force of nearly 15 pounds for
every inch of the area of the pifton. Now when one pi-
iton H is at the bottom of the barrel, the other K is at
the top of the barrel, and the air below K is equally
rare with that in the receiver. Therefore the prefiure
of the external air on the pifton K is nearly equal to
that on the pifton H. Both, therefore, are ahlmg in
oppofite dire&ions on the wheel which gave them mo¬
tion and the force necefiary for railing H is only the
difference between the elafticity of the air in the barrel
H and that of the air in the barrel K. This is very
fmall in the beginning of the ftroke, but gradually in-
creafes as the pifton K defcends, and becomes equal to
the whole excels of the air’s preffure above the elafticity
of the remaining air of the receiver when the air at K of
the natural deniity begins to open the pifton valves.
An accurate attention to the circumftances will Ihow us
that the force requifite for working the pump is greateft
at firft, and gradually diminifhes as the rarefaction ad¬
vances •, and when this is nearly complete, hardly any
more force is required than what is neceffary for over¬
coming the friftion of the piftons, except during the dif-
charge of the air at the end of each ftroke.
This is therefore the form of the air-pump which is
moft generally ufed all over Europe. Some traces of
national prepolfeftion remain. In Germany, air-pumps
are frequently made after the Original model of Gue¬
ricke’s (Wolff' Cyclomathefis) 5 and the French general¬
ly ufe the pump made by Papin, though extremely auk-
ward. We fliall give a defeription of Boyle’s air-pump
as finally improved by Hawkefbee, which, with fome
fmall accommodations to particular views, ftill remains
the moft approved form.
Here follows the defeription from Defaguliers.
It confifts of two brafs barrels aa,aa (fig. 19.), 12
inches high and 2 wide. The piftons are railed and de-
prefled by turning the vinch b b. This is f^ftened to an
axis palling through a ftrong toothed wheel, which lays
hold of the teeth of the racks c c c c. Then the one
is raifed while the other is deprefled ; by which means
the valves, which are made of limber bladder, fixed in
the upper part of each pifton, as well as in the open¬
ings into the bottom of the barrels, perform their office
of difeharging the air from the barrels, and admitting
into them the air from the receiver to be afterwards dif-
charged; and when the receiver comes to be pretty
well exhaufted of its air, the preffure of the atmofphere
in the defeending pifton is nearly fo great, that the
power required to raife the other is little more than is
neceffary for overcoming the friction of the pifton, which
renders this pump preferable to all others, which require
more force to work them as the rarefaction of the air in
the receiver advances.
The barrels are fet in a brafs dilh about two inches
deep, filled with water or oil to prevent the infinuation
of air. The barrels are ferewed tight down by the nuts
e e, e e, which force the frontifpiece ff down on them,
through which the two pillars g g. gg pafs.
Vgl. XVI. Part II,
From between the barrels rifes a {lender brafs pipe h h, Air-pump,
communicating with each by a perforation in the tranf- -v-—
verfe piece of brafs on which they ftand. The upper end Brafs°^jpe
of this pipe communicates with another perforated piece ’
of brafs, which ferews on underneath the plate f iif, of
ten inches diameter, and furrounded with a brafs rim
to prevent the {bedding of water ufed in fome experi¬
ments. This piece of brafs has three branches: ift.
An horizontal one communicating with the conduit
pipe h h. 2d, An upright one ferewed into the middle
of the pump-plate, and terminating in a fmall pipe £,
riling about an inch above it. 3d, A perpendicular one,
looking downwards in the continuation of the pipe
£, and having a hollow ferew in its end receiving the
brafs cap of the gage-pipe ////, which is of glafs, 34
inches long, and immerfed in a glafs ciitern m m filled
with mercury. This is covered a-top with a cork float,
carrying the weight of a light wooden fcale divided into
inches, which are numbered from the furface of the mer¬
cury in the ciftern. This fcale will therefore rife and
fall with the mercury In the ciftern, and indicate the
true elevation of that in the tube. 105
There is a ftopcock immediately above the infertion Stopcock,
of the gage-pipe) by tvhich its communication may be
cut off. There is another at «, by which a communi¬
cation is opened with the external air, for allowing its
readmiflion } and there is fometimes another immediately
within the infertion of the condu61-pipe for cutting off
the communication between the receiver and the pump.
This is particularly ufeful when the rarefaction is to be
continued long, as there are by thefe means fewer
chances of the infinuation of air by the many joints.
The receivers are made tight by fimply fetting them Receiver?,
on the pump-plate with a piece of w et or oiled leather
between •, and the receivers which are open a-top, have
a brafs cover fet on them in the fame manner. In thefe
covers there are various perforations and contrivances for
various purpofes. The one in the figure has a {lip w ire
palling through a collar of oiled leather, having a hook
or a ferew in its lower end for hanging any thing on ©r
producing a variety of motions. I0^
Sometimes the receivers are fet on another plate, which Contri-
has a pipe ferewed into its middle, furnithed with a flop- vance for
cock and a ferew, which fits the middle pipe k. When rLIT10vluS
the rarefaflion has been made in it, the cock is {hut, and theni‘
then the whole may be unferewed from the pump, and
removed to any convenient place. This is called a tranf-
porter plate. _ Io8
It only remains to explain the gage ////. In the Principle
ordinary ftate of the air its elafticity balances the pref-uPon whk ^
fure of the incumbent atmcfphere. We find this fromthei?a^.18
the force that is neceffary to fqueeze it into lefs bulked" ^
in oppofition to this elafticity. Therefore the elaftici- *
ty of the air increafes with the vicinity of its particles.
It is therefore reafonable to expefl, that when we al¬
low it to occupy more room, and its particles are far¬
ther afunder, its elafticity will be diminilhed though
not annihilated ; that is, it will no longer balance the
WHOLE preffure of the atmofphere, tliough it may ftill
balance part of it. If therefore an upright pipe have
its lower end immerfed in a veffel of mercury, and com¬
municate by its upper end with a veffel containing rare¬
fied, therefore lefs elaftic, air, we ftiould expeft that the
preffure of the air will prevail, and force the mercury
into the tube, and caufe it to rife to fuch a height that
4 R the
4
682
PNEUMATICS.
Air-pump.
109-
fo as to in¬
dicate the
degree of
rarefaction.
110
Inconveni¬
ences of this
SaSe>
Fig.. 20.
nt
remedied.
Fig.^i.
the weight of the mercury, joined to the elafticity of the
rarefied air a&ing on its upper furface, fhall be exactly
equal to the whole preffure of the atmofphere. The
height of the mercury is the exa£l meafure of that part
of the whole preiTure which is not balanced by the ela-
liicily of the rarefied air, and its deficiency from the
height of the mercury in the Toricellian tube is the
exadt meafure of this remaining elaflicity.
It is evident therefore, that the pipe will be a fcale of
the elafticity of the remaining air, and will indicate in
fome (brt the degree of rarefaction : for there muft be
fome analogy between the denfity of the air and its
elafticity ; and we have no reafon to imagine that they
do not increafe and diminith together, although we may
be ignorant of the law’, that is, of the change of elaftici¬
ty correfponding to a known change of denfity. This
is to be difcovered by experiment ; and the air-pump
itfelf furnifties us with the beft experiments for this pur-
pofe. After rarefying till the mercury in the gage has
attained half the height of that in the Toricellian tube,
Ihut the communication with the barrels and gage, and
admit the water into the receiver. It will go in till
all is again in equilibrio with the prefiure of the atmo¬
fphere ; that is, till the air in the receiver has collap-
fed into its natural bulk. This we can accurately mea¬
fure, and compare with the whole capacity of the re¬
ceiver ^ and thus obtain the precife degree of rarefaCtion
correfponding to half the natural elafticity. We can
do the fame thing with the elafticity reduced to one
third, one fourth, &c. and thus difcover the whole law.
This gage muft be confidered as one of the moft in¬
genious and convenient parts of Hawketbee’s pump 3
and it is well difpofed, being in a fituation protected
againft accidents : but it neceffarily increafes greatly
the fize of the machine, and cannot be applied to the
table-pump, reprefented in fig. 20. When it is wanted
here, a fmall plate is added behind, or between the bar¬
rels and receiver 3 and on this is fet a fmall tubulated (as
it is termed) receiver, covering a common weather-glafs
tube.—This receiver being rarefied along with the other,
the preffure on the mercury in the ciftern arifing from
the elafticity of the remaining air is diminiftied fo as
to be no longer able to fupport the mercury at its full
height 3 and it therefore defcends till the height at
which it ftands puts it in equilibrio with the elafticity.
In this form, therefore, the height of the mercury is di-
reflly a meafure of the remaining elafticity 3 while in
the other it meafures the remaining unbalanced preffure
of the atmofphere. But this gage is extremely cum-
berfome, and liable to accidents. We are feldom much
interefted in the rarefa£lion till it is great: a contracted
form of this gage is therefore very ufeful, and was early
ufed. A fyphon ABCD (fig. 21.), each branch of
which is about four inches long, clofe at A and open at
D, is filled with boiling mercury till it occupies the
branch AB and a very fmall part of CD, having its fur-
face at O. This is fixed to a fmall Hand, and fixed into
the rectiver, along with the things that are to be exhi¬
bited in the rarefiefi air. When the air has been rare¬
fied till its remaining elafticity is not able to fupport
the column BA, the mercury defcends in AB, and rifes
in CD, and the remaining elafticity will always be mea-
fured by the elevation of the mercury in AB above
that in the leg CD. Could the exhauftion be perfeCled,
ihe furfaces in both kgs would be on a level. Another
gage might be put into tile fame foot, having a 'fmall Air-pump,
bubble of air at A. This would move from the begin- —-y—
r.ing of the rarefaction 3 but our ignorance of the ana¬
logy between the denfity and elafticity hinders us from
ufing it as a meafure of either.
It is enough for our prefent purpofe to obferve, that
the barometer or fyphon gage is a perfect indication
and meafure of the performance of an air-pump, and
that a pump is {cceteris paribus') fo much the more per-
fe6f, as it is able to raife the mercury higher in the gage. r x;
It is in this way that we difcover that none can pro- a complete
duce a complete exhauftion, and that their operation exhauftion
is only a very great rarefaction : for none can raife the
mercury to that height at which it ftands in the Toricel- ^im^e a
lian tube, well purged of air. Few pumps will bring it1
within one-tenth of an inch. Hawkefbee’s, fitted up
according to his inftruCfions, will feldom bring it with¬
in one-fifth. Pumps with cocks, when ccnftrudted ac¬
cording to the principles mentioned when fpeaking of
the exhaufting fyringe, and new and in fine order, will
in favourable circumftances bring it within one-fortieth.
None with valves fitted up with wet leather, or when
water or volatile fluids are allowed accefs into any part,
will bring it nearer than one-fifth. Nay, a pump of the
beft kind, and in the fineft order, will have its rarefying
power reduced to the loweft ftandard, as meafured by
this gage, if we put into the receiver the tenth part of a
fquare inch of white iheep-fkin, frefn from the (hops, or
of any fubftar.ee equally damp. This is a difeoverjr
made by means of the improved air-pump, and leads to
very extenfive and important confequences in general
phyfics 3 fome of which will be treated of under this ar¬
ticle : and the obfervation is made thus early, that our
readers may better underftand the improvements which
have been made on this celebrated machine. IX „
It would require a volume to deferibe all the changes Various
which have been made on it. An inftrument of fuch improve-
multifarious ufe, and in the hands of curious men, each
diving into the fecrets of nature in his favourite line,
this ma¬
chine,
rnuft have received many alterations and real improve¬
ments in many particular refpects. But thefe are befide
our prefent purpofe 3 which is to confider it merely as a
machine for rarefying elaftic or expanfive fluids. We muft
therefore confine ourfelves to this view of it 3 and {hail
carefully ftate to our readers every improvement founded
on principle, and on pneumatical laws. fr
All who ufed it perceived the limit fet to the rarefac- by at.
tion by the refiftance of the valves, and tried to perfect tempting
the conftruftion of the cocks. I he abbe Nollet and t0 perfect
Gravefande, two of the moft eminent experimental phi- of
lofophers in Europe, were the moft: fuccefsful. tbe
Mr Gravefande juftly preferred Hooke’s plan of a 1x5
double pump, and contrived an apparatus for turning Grave-
the cocks by the motion of the pump’s handle. This
is far from either being fimple or eafy in working 3 and ' C ’
occafions great jerks and concuflions in the whole ma¬
chine. This, however, is not neceffarily connefted
with the truly pneumatical improvement. . His pifton
has no valve, and the rod is connefted with it by a
ftirrup D (fig. 22.), as in a common pump. The rod Fig. 22^
has a cylindric part cp, which paffes through the ftir¬
rup, and has a ftiff motion in it up and down of about
half an inch 3 being flopped by the fhoulder c above
and the nut below. The round plate fupported by this
ftirrup has a fhort fquare tube n which fits tight into
.. .the
Air-pump
116
ani raan-
«er af ufmg
it.
121
Highly ex¬
tolled, but
its opera¬
tions.
tKe hole of a piece of cork F.
a fquare fhank g, which goes into the fquare tube n d.
A piece of thin leather foaked in oil, is put between
the. cork and the plate E, and another between the cork
and the plate which forms the foie of the ftirrup. All
thefe pieces are fcrewed together by the nail whofe flat
head covers the hole n. Suppofe, therefore, the pifton
touching the bottom of the barrel, and the winch turn¬
ing to raife it again, the friftion of the pifton on the
barrel keeps it in it* place, and the rod is drawn up
through the ftirrup D. Thus the wheel has liberty to
turn about an inch ; and this is fufficient for turning the
cock, fo as to cut off the communication with the ex¬
ternal air, and to open the communication with the re¬
ceiver. This being done, and the motion of the winch
continued, the pifton is raifed to the top of the barrel.
When the winch is turned in the oppofite direction, the
pifton remains fixed till the cock is turned, fo as to ftxut
the communication wfith the receiver, and open that with
the external air.
This is a pretty contrivance, and does not at firft ap¬
pear neceffary ; becaufe the cocks might be made to turn
at the beginning and end of the ftroke without it. But
this is juft poflible ; and the fmalleft error of adjuftment,
or wearing of the apparatus, will caufe them to be open
at improper times. Befides, the cocks are not turned
in ah inftant, and are improperly open during fome very
fmall time; but this contrivance completely obviates
this difficulty.
The cock is precifely fimilar to that formerly defcrib-
ed, having one perforation diametrically through it, and
another entering at right angles to this, and after reach¬
ing the centre, it paffes along the axis of the cock, and
comes out to the open air.
It is evident, that by this conftruftion of the cock,
the ingenious improvement of Dr Hooke, by which the
preffure of the atmofphere on one pifton is made to
balance (in great part) the preffure on the other, is given
up : for, whenever the communication with the air is
opened, it ruflies in, and immediately balances the pref¬
fure on the upper fide of the pifton in this barrel; fo
that the whole preffure in the other muft be overcome
by the perfon working the pump. Gravefande, aware
of this, put a valve on the orifice of the cock ; that is,
tied a flip of wTet bladder or oiled leather acrofs it j and
now the pifton is preffed down, as long as the air in the
barrel is rarer than the outward air, in the iame manner
as when the valve is in the pifton itfelf.
This is all that is neceffary to be defcribed in Mr
Gravefande’s air-pump. Its performance is highly ex¬
tolled by him, as far exceeding his former pumps with
valves. The fame preference wras given to it by his
fucceffor Mufchenbroek. But, while they both prepar¬
ed the piftons and valves and leathers, of the pump,
by fteeping them in oil, and then in a mixture of water
and fpirits of wine, we are certain that no juft eftimate
could be made of its performance. For with this prepa¬
ration it could not bring the gage within one-fifth of an
inch of the barometer. We even fee other limits to its
rarefaction : from its con ft ruction, it is plain that a very
confiderable fpace is left between the pifton and cock,
not lefs than an inch, from which the air is never ex¬
pelled j and if this be made extremely fmall, it is plain
that the pump muft be worked very flow, otherwife
there will not be time for the air to diffufe itfelf from
PNEUMATIC <?. 683
The round plate E has the receiver into the barrel, efpecially towards the end, Air-pump.
wrhen the expelling force, viz. the elafticity of the re- v f
maining air, is very fmall. There is alfo the fame li- In 0**3re_
mit to the rarefaction, as in Hooke’s or Hawkefbee’s fpedl infe-
pump, oppofed by the valve E, which will not open till rior to
the air below the pifton is confiderably denfer than the
external air : and this pump foon loft any advantagesbee
it poffeffed when frefh from the workman’s hands, by
the cock’s growing loofe and admitting air. It is fur-
prifing that Gravefande- omitted Hawhelbee’s fecurity
againft this, by placing the barrels in a difti filled with
oil 3 which would effectually have prevented this incon¬
venience. 124
We muft not omiba feemingly paradoxical obfervation Advantage
of Gravefande, that in a pump conftruCted with valves, °e]^101tbar‘
and worked with a determined uniform velocity, the re¬
quired degree of rarefaCtion is fooner produced by ftiort
barrels than by long ones. It wrould require too much
time to give a general demonftration of this, but it will
eafily be feen by an example. Suppofe the long barrel
to have equal capacity wdth the receiver, then at the end
of the firft ftroke the air in the receiver will have one-
half its natural denfity. Now, let the ftiort barrels have
half this capacity : at the end of the firft ftroke the den¬
fity of the air in the receiver is twro-thirds, and at the
end of the fecond ftroke it is four-ninths, which is lefs
than one-half, and the two ftrokes of the ftiort barrel
are fuppofed to be made in the fame time with one of
longeft, &c. I2£
Haw-kefbee’s pump maintained its pre-eminence with- Smeatort
out rival in Britain, and generally too on the continentj improves
except in France, where every thing took the ton of thetbe va^v®*‘
Academy, which abhorred being indebted to foreigners PumP
for any thing in fcience, till about the year 1750, when
it engaged the attention of Mr John Smeaton, a perfon
of uncommon knowdedge, and fecond to none but Dr
Hooke in fagacity and mechanical refource. He was
then a maker of philofophical inftruments, and made
many attempts to perfeCl the pumps with cocks, but
found, that whatever perfeftion he could bring them to,
he could not enable them to preferve it 3 and he never
would fell one of this conftru&ion. He therefore at¬
tached himfelf folely to the valve ptimps.
The firft thing was to diminiffi the refiftance to thebyenJar-
entry of the air from the receiver into the barrels : this gmg; ’he
he rendered almoft nothing, by enlarging the furface on valve-hole,
which this feebly elaftic air was to prefs. Inftead of
making thefe valves to open by its preffure on a circle of
one-twentieth of an inch in diameter, he made the valve-
hole one inch in diameter, enlarging the furface 400
times 3 and, to prevent this piece of thin leather from
being burft by the great preffure on it, whfcn the pifton
in its defcent w'as approaching the bottom of the barrel,
he fupported it by a delicate but ftrong grating, dixdding
the valve-hole like the fedlion of a honey-comb, as re-
prefented in fig. 25.3 and the ribs of this grating are Fig. 25*
feen edgewufe m fig. 23. at « br. Fig. 23.
The valve xvas a piece of thin membrane or oiled - 127
v. AiiCiUUi aiiC Ul Ui-t u I
filk, gently drained over the mouth of the valve-hole, the ftrucl
and tied on by a fine filk thread wound round it in the ture of the
fame manner that the narrow flips had been tied on valve, and
formerly. This done, he cut with.a pointed knife the
leather round the edge, nearly four quadrantal arcs,
leaving a fmall.tongue between each, as in fig. 25. The Fig- 25.
drained valve immediately flmnks inxv-af^s, as reprefent-
4 R 2 ed
6 84
PNEUMATICS.
Air-pump, ed by tbe fliaded parts*, and tbe ftrain by which it is
1 kept down is now greatly diminilhed, taking place only
at the corners. The gratings being reduced nearly to
an edge (but not quite, left they fliould cut), there is
vefy little preffure to produce adhefion by the clammy
oil. Thus it appears, that a very fmall elafticity of the
air in the receiver will be fufficient to raife the valve 5
and Mr Smeaton found, that when it was not able to
do this at firlt, when only about -g^o of the natural elaf¬
ticity, it would do it after keeping the pifton up eight
or ten feconds, the air having been all the while under¬
mining the valve, and gradually detaching it from' the
grating.
Unfortunately he could not follow this method with
the pillon valve. There was not room round the rod
for fuch an expanded valve ; and it would have obliged
him to have a great fpace below the valve, from which
he could not expel the air by the defcent of the piiton.
His ingenuity hit on a way of increafing the expelling
force through the common valve ; he' inclofed the rod of
the pifton in a collar of leather /, through which it
moved freely without allowing any air to get paft its
tides. For greater fecurity, the collar of leather was
contained in a box terminating in a cup filled with oil.
As this makes a material change in the principle of con-
ftru£Hon of the air-pump (and indeed of pneumatic en¬
gines in general), and as it has been adopted in all the
fubfequent attempts to improve them, it merits a parti¬
cular confideration.
The pifton itfelf confifts of two pieces of brafs faften-
ed by fcrews from below. The uppermoft, which is of
one folid piece with the rod GH (fig. 23.) is of a dia¬
meter fomewhat lefs than the barrel *, fo that when they
are fcrewed together, a piece of leather foaked in a
mixture of boiled oil and tallow, is put between them $
and when the pifton is thruft into the barrel from above,
the leather comes up around the fide of the pifton, and
fills the barrel, making the pifton perfeftly air-tight.
The lower half of the pifton projects upwards into the
upper, which has a hollow gb c d lo receive it. There
is a fmall hole through the lowxr half at a to admit the
air *, and a hole c dm the upper half to let it through,
* and there is a flip of oiled filk ftrained acrofs the hole a
by way of valve, and there is room enough left ztbc for
this valve to rife a little when prefled from below. The
rod GH paflfes through the piece of brafs which forms
the top of the barrel fo as to move freely, but without
any fenfible (hake : this top is formed into a hollow box,
confifting of two pieces ECDF and CNOD, wThich
fcrew together at CD. This box is filled with rings of
oiled leather exa&ly fitted to its diameter, each having
a hole in it for the rod to pafs through. When the
piece ECDF is fcrew'ed down, it compreffes the leathers;
fqueezing them to the rod, fo that no air can pafs be¬
tween them } and, to fecure us againft all ingrefs of air,
the upper part is formed into a cup EF, which is kept
filled with oil.
The top of the barrel is alfo pierced with a hole LK,
which rifes above the flat furface NO, and has a flip of
oiled filk tied over it to aft as a valve 5 opening when
preffed from below, but (hutting when prefled from
above.
The communication between the barrel and receiver
is made by means of the pipe ABPQ; and there goes
frpm the hole K in the top of the barrel a pipe KRST,
128
increafing
the expel¬
ling force.
129
Sttufiure
of his pi¬
fton for
this pur-
pofe.
Fig. 23.
which either communicates with the open air or with Air-pump,
the receiver, by means of the cock at its extremity T. v--—'
The conduit pipe ABP£> has alfo acock at by which
it is made to communicate either with the receiver or
with the open air. Thefe channels of communication
are varioufly conducted and terminated, according to
the views of the maker : the Ikctch in this figure is fuf¬
ficient for explaining the principle, and is fuited to the
general form of the pump, as it has been frequently
made by Nairne and other artifts in London. ^
Let us now fuppofe the pifton at the top of the barrel, gUperjor;ty
and that it applies to it all over, and that the air in the of this con-
barrel is very much rarefied : in the common pump the ^‘ action,
pifton valve is prefled hard down by the atmofphere, and
continues (hut till the pifton gets far down, condenfes
the air below it beyond its natural date, and enables it
to force up the valves. But here, as foon as the pifton
quits the top of the barrel, it leaves a void behind it j
for no air gets in round the pifton rod, and the valve at
K is (hut by the preflure of the atmofphere. There is
nothing now to oppofe the elafticity of the air below
but the ftiffnefs of the valve be; and thus the expelling
(or more accurately the liberating) force is prodigioufly
increafed. I^I
The fuperiority of th:s conftruction will be beft feen (hown by
by an example. Suppofe tbe ftiffnefs of the valve equal an exatn-
to the weight of tq of an inch of mercury, when the ba- Py¬
rometer Hands at 30 inches, and that the pump-gage
(lands at 29.9 5 then, in an ordinary pump, the valve in
the pifton will not rife till the pifton has got within the
300th part of the bottom of the barrel, and it will leave
the valve-hole filled with air of the ordinary denfity.
But in this pump the valve will rife as foon as the pifton
quits the top of the barrel -, and when it is quite downj
the valve-hole a will contain only the 300th part of the
air which it would have contained in a pump of the or¬
dinary form. Suppofe farther, that the barrel is of
equal capacity with the receiver, and that both pumps
are fo badly conftrudted, that the fpace left below the
pifton is the 300th part of the barrel. In the common
pump the pifton valve will rife no more, and tbe ra¬
refaction can be carried no farther, however delicate
the barrel valve may be j but in this pump tbe next
ftroke will raife the gage to 29.95, and the pifton valve
will again rife as foon as the pifton gets half way down
the barrel.
The limit to the rarefaction by this pump depends
chiefly on the fpace contained in the hole LK, and in
the fpace be d oi the pifton. When the pifton is brought
up to the top, and applied clofe to it, thofe fpaces re¬
main filled with air of the ordinary denfity, which will
expand as the pifton defcends, and thus will retard the
opening of the pifton valve. The rarefaCtion will (top
when the elafticity of this fmall quantity of air, expand¬
ed fo as to fill the whole barrel (by the defcent of the
pifton to the bottom), is juft equal to the force requifite
for opening the pifton valve. -
Another advantage attending this conftruCtion is, jt js eaf[]j-
that in drawing up the pifton, we are not refitted by worked,
tbe whole preffure of the air *, becaufe the air is rarefied
above this pifton as well as below it, and the pifton is in
precifely the fame (late of preflure as if connected with
another pifton in a double pump. The refiftance to
the afeent of the pifton is the excefs of the elafticity of
the air above it over the elafticity t»f the air below :
this,
0
A'r-puinp. this, toward the end of the rarefaction, is very fmall,
>—-y while the pifton is near the bottom of the barrel, but
gradually increafes as the pifton rifes, and reduces the
air abotfe it into fmaller dimenlions, and becomes equal
to the preflure of the atmofphere, when the air above
the pifton is of the common deuftty. If we ihould mile
the pifton ftill farther, we muft condenfe the air above
it : but Mr Smeaton has here made an blue lor the air
by a fmall hole in the top of the barrel, covered with a
delicate valve. This allows the air to efcape, and Ihuts
again as loon as the pifton begins to defcend, leaving
aimoft a perfeCt void behind it as before.
This pump has another advantage. It may be chan¬
ged in a moment from a rarefying to a condenfing en¬
gine, by limply turning the cocks at Q and T. While
T communicates with the open air and Q with the re¬
ceiver, it is a rarefying engine or air-pump : but when
T communicates with the receiver, and with the open
Plate a^r’ a condenfing engine.
CCCCXXVI Fig- 2b. reprefents Mr Smeaton’s air-pump as it is
Fw 26. ufually made by Nairne. Upon a folid bafe or table
133 are let up three pillars F, H, H : the pillar F fupports
Defcription ^]ie pump-plate A : and the pillars H, H, fupport the
ofSmea- fronf- or head, containing a brafs cog-wheel, which is
ton pum. turnecj hhe handle B, and works in the rack C fal-
tened to the upper end of the pifton rod. The whole
is ftill farther fteadied by two pieces of brals c b and 0
k, which conned the pump-plate with the front, and
have perforations communicating between the hole a in
the middle of the plate and the barrel, as will be de-
fcribed immediately. DE is the barrel of the pump,
firmly fixed to the table byfcrews thro’ its upper flanch :
e f d c is a fiender brafs tube fcrewed to the bottom of
the barrel, and to the under hole of the horizontal ca¬
nal c b. In this canal there is a cock which opens a
communication between the barrel and the receiver,
when the key is in the pofition reprefented heie : but
when the key is at right angles with this pofition, this
communication is cut off. If that fide of the key which
is here drawn next to the pump-plate be turned outward,
the external air is admitted into the receiver •, but if
turned inwards, the air is admitted into the barrel.
g h Is another (lender brafs pipe, leading from the dif-
charging valve at g to the horizontal canal h h, to the
under fide of which it is fcrewed fall. In this horizon¬
tal canal there is a cock n which opens a paffage from
the barrel to the receiver when the key is in the pofition
here drawn •, but opens a paffage from the barrel to the
external air when the key is turned outwards, and from
the receiver to the external air when the key is turned
inwards. This communication with the external air is
not immediate but through a fort of box 1; the ufe of
this box is to receive the oil which is difcharged through
the top valve c^. In order to keep the pump tight, and
in working order, it is proper fometimes to pour a table-
ipoonful of olive oil into the hole a of the pump-plate,
and then to work the pump. The oil goes along the
conduit b c df e, gets into the barrel and through the
pifton-valve, when the pifton is preffed to the bottom of
the barrel, and is then drawn up, and forced through
the difcharging valve g along the pipe g h, the horizon¬
tal paffage h », and finally into the box i. This box
has a fmall hole in its fide near the top, through which
the air efcapes.
From the upper fide of the can ale b there arifes a
PNEUMATICS. 685
{lender pipe which bends outward and then turns down- Air-pump.
wards, and is joined to a fmall box, which cannot be'
feen in this view. From the bottom of this box pro¬
ceeds downwards the gage-pipe of glafs, which enters
the ciftern of mercury G fixed below.
On the upper fide of the other canal at 0 is feen a
fmall ftud, having a lliort pipe of glals projecting hori¬
zontally from it, clofe by and parallel to the front piece
of the pump, and reaching to the other canal. This
pipe is clofe at the farther end, and has a fmali drop of
mercury or oil in it at the end 0. This ferves as a gage
in condenfing, indicating the degree of condenfation by
the place of the drop : For this drop is forced along tire
pipe, condenfing the air before it in the fame degree
that it is condenfed in the barrel and receiver.
In conftrufling this pump, Mr Smeaton introduced Method of
a method of joining together the different pipes and other joining to-
pieces, which has great advantages over the ufual man-2ethe1' Ac
ner of {brewing them together with leather between, and
i34
ditTer«nt
pipes, See.
which is now much ufed in hydraulic and pneumatic en-1
gines. We {hall explain this to our readers by a defcrip¬
tion of the manner in which the exhaufting gage is join¬
ed to the horizontal diuft c b.
The piece h i />, in fig. 23. is the fame with the little Fig. 23.,
cylinder obfervable on the upper fide of the horizontal
canal c d, in fig. 26. The upper part h / is formed in-Fig. 26.
to an ouliide ferew, to fit the hollow ferew of the piece
deed. The top of this laft piece has a hole in its mid¬
dle, giving an eafy paffage to the bent tube c b a, fo as
to {lip along it with freedom. To the end c of this
bent tube is foldered a piece of brafs c f g, perforated in
continuation of the tube, and having its end ground fiat
on the top of the piece h ip, and alfo covered with a
ilip of thin leather {trained acrofs it and pierced with a
hole in the middle.
It is plain from this form, that if the furface f g be.
applied to the top of h i, and the cover d e e dbz fcrew¬
ed down on it, it will draw or prefs them together, fo
that no air can efcape by the joint, and this without
turning the whole tube c b a round, as is neceffary in
the ufual way. This method is now adopted for joining
together the conducting pipes of the machines for ex-
tinguifhing fires, an operation which was extremely
troublefome before this improvement.
The conduit pipe IL ef c (fig. 26.) is faffened to the Fig. 25.
bottom of the barrel, and the difcharging pipe g h to its
top, in the fame manner. But to return to the gage ;
the bent pipe c b a enters the box r t near one fide, and
obliquely, and the gage pipe q r is inferted through its
bottom towards the oppofite fide. The ufe of this box
is to catch any drops of mercury which may fometimes.
be dallied up through the gage pipe by an accidental
ofcillation. This, by going through the paflages of the
pump, would corrode them, and would abt particularly
on the joints, which are generally foldered with tin.
When this happens to an air-pump, it muft be cleaned
with the moft fcrupulous attention, otherwife it will be
quickly deftroyed. -
This account of Smeaton’s pump is fufficient for ena-Great
bling the reader to underftand its operation and to fee P°wers ot
its fuperiority. It is reckoned a very fine pump of the
ordinary conftruClion which will rarefy 200 times, or ° /
raife the gage to 29.85, the barometer Handing at 30.
But Mr Smeaton found, that his pump, even after lone?
ufing, railed it to 29.95, which we confider as equiva¬
lent .
686
PNEUMATICS,
136
Another
ton’s
Fig. 27,
Air-pnmp. lent to rarefying 600 times. When in fine order, he
'“”~v found no bounds to its rarefaction, frequently raifing the
gage as high as the barometer-, and he thought its per¬
formance fo perfeCt, that the barometer-gage was not
fufficiently delicate for meafuring the rarefaCtion. He
therefore fubftituted the fyphon gage already defcribed,
which he gives fome reafons for preferring ; but even
this he found not fufficiently fenfible.
He contrived another, which could be carried to
contrivance any degree of fenfibility. It confifted of a glafs body
ot Smea- 27.), of a pear ffiape, and was therefore called
the pear-gage. This had a fmall projecting orifice at
B, and at the other end a tube CD, whofe capacity was
tbe hundredth part of the capacity of the whole veffel.
This was fufpended at the flip-wire of the receiver, and
there was fet below it a fmall cup with mercury. When
the pump was worked, the air in the pear-gage was ra¬
refied along with the reft. When the rarefaCtion was
brought to the degree intended, the gage was let down
till B reached the bottom of the mercury. The exter¬
nal air being now let in, the mercury was raifed into
the pear, and flood at fome height E in the tube CD.
The length of this tube being divided into 100 parts,
DE
and thofe numbered from D, it is evident that =-7- will
' DB
exprefs the degree of rarefaCtion which had been pro¬
duced when the gage was immerfed into the mercury :
or if DC be of the whole capacity, and be divided
into 100 parts by a fcale annexed to it, each unit of
*37
very ingeni-
the fcale will be
r=- of the whole.
138 ,
It excited
the atten-
This wras a very ingenious contrivance, and has been
the means of making fome very curious and important
difeoveries which at prefent engage the attention of phi-
lofophers. By this gage Mr Smeaton found, that his
pump frequently rarefied a thoufand, ten thoufand, nay
an hundred thoufand times. But though he in every
inftance faw the great fuperiority of his pump above all
others, he frequently found irregularities which he could
not explain, and a want of correfpondence between the
pear and the barometer gages which puzzled him. The
pear-gage frequently indicated a prodigious rarefaClion,
when the barometer-gage would not ftiow more than
600.
Thefe unaccountable phenomena excited the curiofity
tion of the philofophers, who by this time were making continual
literary ufe of the air-pump in their meteorological refearches,
world. and much interefted in every thing connected with the
ftate or conftitution of elaftic fluids. Mr Nairne, a
moft ingenious and accurate maker of philofophical in-
ftruments, made many curious experiments in the exa¬
mination and comparifon of Mr Smeaton’s pump with
thofe of the ufual conftruclion, attending to every cir-
cumftance which could contribute to the inferiority of
the common pumps or to their improvement, fo as to
bring them nearer to this rival machine. This rigorous
comparifon brought into view feveral circumftances in
the conftitution of the atmofpheric air, and its relation
to other bodies, which are of the moft extenfive and im¬
portant influence in the operations of nature. We ffiall
notice at prefent fuch only as have a relation to the
Expert operation of the air-pump in extracting air from the
ments with receiver.
it by Mr Mr Nairne found, that when a little water, or even
Nairne 0f paper damped with water, was expofed under
the receiver of Mr Smeaton’s air-pump, tvhen In the Aar ptuop*
moft perfect condition, raifing the mercury in the baro- y—
meter-gage to 29.95, Could not make it rife above
29.8 if Fahrenheit’s thermometer indicated the tempe¬
rature 470, nor above 29.7 if the thermometer flood at
550; and that to bring the gage to this height and keep
it there, the operation of the pump muft be continued
for a long time after the water had difappeared or the
paper become perfectly dry. He found that a drop of
fpirits, or paper moiftened with fpirits, could not in
thofe circumftances allow the mercury in the gage to
rife to near that height 3 and that limiiar effedls follow¬
ed from admitting any volatile body whatever into the
receiver or any part of the apparatus.
This ftiowed him at once how improper the direc-Ibow the
tions were which had been given by Guericke, Boyle, IinProPn’e'
Gravefande, and others, for fitting up the air-pump for
experiment, by foaking the leather in water, coveringtfify
the joints with water, or in ftiort, admitting water or water,
any other volatile body near it. * I4I
He therefore took his pumps to pieces, cleared them and the
of all the moifture which he could drive from them by utility of
heat, and then leathered them anew w ith leather leaked
in a mixture of olive oil and tallow, from which he had low>*
expelled all the water it ufually contains, by boiling it
till the firft frothing was over. When the pumps were
fitted up in this manner, he uniformly found that Mr
Smeaton’s pump rarefied the gage to 29 95, and the
bell common pump to 29.87, the firft of which he com¬
puted to indicate a rarefaction to 600, and the other to
230. But in this ftate he again found that a piece of
damp paper, leather, wood, &c. in the receiver, reduced
the performance in the fame manner as before. 1^2
But the moft remarkable phenomenon was, that when A remark-
he made ufe of the pear-gage with the pump cleared from phen*^
all moifture, it indicated the fame degree of rarefaction menon
with the barometer-gage : but when he expofed a bit
of paper moiltened with fpirits, and thus reduced the
rarefatftion of the pump to what he called 50, the baro¬
meter gage Handing at 29.4, the pear-gage indicated a
rarefaction exceeding 100,000 3 in fhort, it was not
meafurable 3 and this phenomenon was almoft conftant.
Whenever he expofed any fubftance fufceptible of eva¬
poration, he found the rarefaCtion indicated by the ba¬
rometer-gage greatly reduced, while that indicated by
the pear-gage was prodigicufly increafed 3 and both thefe
effeCts were more remarkable as the fubjeCt was of ealier
evaporation, or the temperament of the air of the cham¬
ber was warmer. ^ ?
This uniform refult fuggefted the time caufe. Water accoUnte4
boils at the temperature 212, that is, it is then converted for.
into a vapour which is permanently elaftic while of that
temperature, and its elafticity balances the preffure of
the atmofphere. If this preffure be diminiftsed by rare¬
fying the air above it, a low temperature will not allow
it to be converted into elaftic vapour, and keep it in
that ftate. Water will boil in the receiver of an air-
pump at the temperature 96, or even under it. Phi-
lofophers did not think of examining the ftate of the va¬
pour in temperatures lower than what produced ebulli¬
tion. But it now appears, that in much lower heats
than this the fuperficial water is converted into elaftic
vapour, which continues to exhale from it as long as
the water lafts, and, fupplying the place of air in the
receiver^
3
PNEUMATICS.
Air-pump, receiver, exerts the Tame elaftieity, and hinders the mer-
cury from rifing in the gage in the fame manner as fo
much air of equal elafticity would have done.
When Mr Nairne was exhibiting thefe experiments
to-the.Honourable Henry Cavendilh in 1776, this gen¬
tleman informed him that it appeared from a feries of
experiments of his father Lord Charles Cavendilh, that
when water is of the temperature 7 2°, it is converted
into vapour, under any preffure lefs than three-fourths
of an inch of mercury, and at 410 it becomes vapour
when the predure is iefs than one-fourth of an inch :
Even mercury evaporates in this manner when all pref¬
fure is removed. A dewy appearance is frequently oli¬
fer ved covering the infide of the tube of a barometer,
where we ufually fuppofe a vacuum. This dew, when
viewed through a microfcope, appears to be a let of de¬
tached globules of mercury, and upon inclining the tube
fo that the mercury may afeend along it, thefe globules
will be all licked up, and the tube become clear. The
dew which lined it was the vapour of the mercury con-
denfed by the fide of the tube j and it is never oblerved
but when one fide is expofed to a ftream of cold air from
a window, See.
To return to the vapour in the air-pump receiver, it
mull be obferved, that as long as the water continues to
yield it, we may continue to work the pump 5 and it
will be continually abftracled by the barrels, and dif-
charged in the form of water, hecaufe it collapfes as
foon as expofed to the external preffure. All this while
the gage will not indicate any more rarefaflion, becaufe
the thing immediately indicated by the barometer-gage
is diminifhsd elqfticity, which does not happen here.
When all the water which the temperature of the room
can keep elaftic has evaporated under a certain preffure,
fuppofe 4- an inch of mercury, the gage Handing at
29.5, the vapour which now fills the receiver expands,
687
from different fuhftances, exhibit remarkable differences Air-pump,
in this refpeft. But we fee from this and other pheno-
mena, which ftiall be mentioned in their proper places,
that the air and vapour are not always intimately united j
and therefore will not always be drawn out together by
the air-pump. But let them be ever fo eonfufedly blen-
.ded, we fee that the air muff come out along with the
vapour, and its quantity remaining in the receiver muft
be prodigioufiy diminifhed by this affociation, probably
much more than could be, had the receiver only con-
-tained pure air. 1^5
Let us now confider what muff happen in the pear-Confequen-
gage. As the air and vapour are continually drawn off
from the receiver, the air in the pear expands and goes the^ear
off with it. We fhail fuppofe that the generated va-andbaro-
pour hinders the gage from rifing beyond 29.5. Du-meter
ring the continued working of the pump, the air in ASes--
the pear, whofe elafticity is 0.5, flowly mixes with
the vapour at the mouth of the pear, and the mix¬
ture even advances into its infide, fo that if the
pumping be long enough continued, what is in the-
pear is nearly of the fame compofition with what is
in the receiver, eonfifting perhaps of 20 parts of vapour
and one part of air, all of the elafticity of 0.5.
When the pear is plunged into the mercury, and the
external air allowed to get into the receiver, the mercu¬
ry rifes in the pear-gage, and leaves not -I- but-—  
! 60 60 X
or  of it filled wifh common air, the vapour ha-
ving collapfed into art invifible atom of water. Thus
the pear-gage will indicate a rarefa&ion of 1200, while
the barometer-gage only fiiovved 60, that is, ftiowed
the elafticity of the included fubftance diminiflied 60
times. The conclufion to be drawn from thefe two
meafures (the one of the rarefaction of air,
^ 1 , . . , and tfce
and by its diminilhed elafticity the gage rifes, and now other of the diminution of elafticity) is, that the matter
fome more water which had been attached to bodies by 'rith which the receiver was filled, immediately before
.chemical or corpufcular attraCHon is detached, and a *1'~ J rr"'~ ~c
new fupply continues to fupport the gage at a greater
.height; and this goes on continually till ahnqft all has
•been abftracled: but there will remain fome which no
art can take away ; for as it paffes through the barrels,
the readmiflion of the air, confifted of cne part of in-
condenfible air, and -
again expands into vapour when we puih the p: ft on down
again. Whenever this happens there is an end of the
14- rarefaction.
Air and While this operation is going on, the air comes out
vapour Bot along with the vapour; but we cannot fay in what pro-
mixedto- Porri°n- If it were always uniformly mixed with the
gether. vapour, it would diminilh rapidly •, but this does not
appear to be the cafe. There is a certain period of
rarefaClion in which a tranfient cloudinefs is perceived
in the receiver. This is watery vapour formed at that
degree of rarefaClion, mingled with, but not diffolved in
or united with, the air, otherwife it would be tranfpa-
rent. A fimilar cloud will appear if damp air be ad¬
mitted fuddenly into an exhaufted receiver. The va¬
pour, which formed an uniform tranfparent mafs with
the air, is either fuddenly expanded and thus detached
from the other ingredient, or is fuddenly let go by the
air, which expands more than it does. We cannot af-
or 20 parts of watery vapour.
The only obfeure part of this account is what relates DiffkJltj
, to the compofition of the matter which filled the pear-in acc°un'c-
and gets between the pifton and the top, it fucceftively gage before the admiffion of the mercury. It is not eafyj.ng for,
collapfes into water during the afeent of the pifton, and to fee how the vapour of the receiver comes in by a nar-'tkfe
asmin exnands into vanour when we rmih the nhlnnrWn row mouth while the air is comingout by the fame paffagei fequenc"^
Accordingly it requires a very long time to produce this
extreme rarefa£Hon in the pear-gage \ and there are
great irregularities in any two fucceeding experiments,
as may be feen by looking at Mr Nairne’s account of
them in the Philofophical Tranfaflions, vol. Ixvii. Some
vapours appear to have mixed much more readily with
the air than others j and there are fome unaccountable
cafes where vitriolic acid and fulphureous bodies were
included, in which the diminution of denfity indicated by
the pear-gage was uniformly lefs than the dimmulion of
elafticity indicated by the .baroipeter-gage. It is enough
for us at prefent to have eftablilhed, by unqueftionable
fa&s, this produftion of elaftic vapour, and the necef-
% of attending to it, both in the conftru&ion of the
air-pump and in drawing refults from experiments exhi- *45
bited in it. The fupe-
MrSmeaton’s pump, when in good order, and per-!;L°ntyof
-firm with probability which of thefe is the cafe : diffe- .. feftly free from all moifture, will in dry weather rarefy exci£sTwo
arent compofitions of air, that is, air loaded with vapours air about 6co times, railing the baremeter-gage to with-new im-
' provements* •>
688
149
Improve¬
ments in
this pump
attempted
IS1
by Ruffel,
Fig. 2S.
P N E U M
in ^5 of an incli of a fine barometer. This was a per¬
formance fo much fuperior to that of all others, and by
means of Mr Nairne’s experiments opened fo new a field
of obfervation, that the air-pump once more became a ca¬
pital inftrument among the experimental philofophers.
The caufes of its fuperiority were alfo fo diitinft, that
artifts were immediately excited to a farther improvement
of the machine j fo that this becomes a new epoch in its
hiftory.
There is one imperfeftion which Mr Smeaton has not
attempted to remove. The difcharging valve is ftill open¬
ed againlt the preifure of the atmofphere. An author
of the Swedilb academy adds a fubfidiary pump to this
valve, which exhaufts the air from above it, and thus
puts it in the fituation of the pifton valve. We do
not find that this improvement has been adopted fo as
to become general. Indeed the quantity of air which
remains in the pzfiage to this valve is fo exceedingly
little, that it does not feem to merit attention. Suppo-
fing the valve hole of an inch wide and as deep (and
it need not be more), it will not occupy more than -g^cr
part of a barrel twelve inches long and two inches
wide.
Mr'Smeaton, by his ingenious conftruftion, has great¬
ly diminiihed, but has not annihilated, the obftrutlions
to the paffage of the air from the receiver into the bar¬
rel. His fuc<!:efs encouraged farther attempts. One of
the fir ft and moft ingenious was that of Profeffor Ruf¬
fel of the univerfity of Edinburgh, who about the year
1770 conftru&ed a pump in which both cocks and valves
were avoided.
The pifton is folid, as reprefented in fig. 28. and its
rod pafles through a collar of leather on the top of the
barrel. This collar is divided into three portions by
two brafs rings a, b, which leave a very fmall fpace round
th» pifton rod. The upper ring a communicates by
means of a lateral perforation with the bent tube, /m «,
which enters the barrel at its middle n. The lower ring
b communicates with the bent tube c d, which commu¬
nicates with the horizontal paffage d c, going to the
middle e of the pump plate. By the way, however, it
communicates alio with a barometer gage p &, Handing
in a ciftern of mercury 0, and covered with a glafs tube
clofe at the top. Beyond <?, on the oppofite circumfer¬
ence of the receiver plate, there is a cock or plug/com¬
municating with the atmofphere.
The pifton rod is clofeiy embraced by the three col¬
lars of leather j but, as already faid, has a free fpace
round it in the two brafs rings. To produce this pref-
fure of the leathers to the rod, the brafs rings which fe-
parate them are turned thinner on the inner fide, fo that
their crofs fedtion along a diameter would be a taper
wedge. In the fide of the pifton rod are two cavities
q r, t s, about one-tenth of an inch wide and deep, and
of a length equal to the thicknefs of the two rings a, b,
and the intermediate collar of leathers. Thefe cavities
are fo placed on the pifton-rod, that when the pifton
is applied to the bottom of the barrel, the cavity t s in
the upper end of the rod has its upper end oppofite to
the ring a, and its lower end oppofite to the ring b, or
to the mouth of the pipe c d. Therefore, if there be a
void in the barrel, the air from the receiver will come
from the pipe c d, into the cavity in the pifton rod, and
by it will get paft the collar of leather between the rings,
and thus will get into the 'fmall interftice between the
Z
A T I C S.
rod and the upper ring, and ihen into the pipe /m «, and Air-pump,
into the empty barrel. When the pifton is drawm up,
the folid rod immediately (huts up this paffage, and the
pifton drives the air through the difcharging valve k.
When it has reached the top of the barrel, and is clofeiy
applied to it, the cavity 7 r is in the fituation in which
t j formerly was, and the communication is again opened
between the receiver and the empty barrel, and the air
is again diffufed between them. Pufhing down the pi¬
fton expels the air by the lower difcharging pipe and
valve hi; and thus the operation may be continued.
This muft be acknowledged to be a moft fimple and
ingenious conftruflion, and can neither be called a cock
nor a valve. It feems to oppofe no obftrutftion w'hat-
ever : and it has the fuperior advantage of rarefying
both during the afcent and the defcent of the pifton,
doubling the expedition of the performance, and the
operator is not oppofed by the preffure of the atmo¬
fphere except towards the end of each ftroke. rl he ex¬
pedition, however, is not fo great as one fhould expeft;
for nothing is going on while the pifton is in motion,
and the operator muft flop a while at the end of each
ftroke, that the air may have time to come through this
long, narrow7, and crooked paffage, to fill the barrel.
But the chief difficulty which occurred in the execu¬
tion arofe from the clammy oil with which it wras ne-
ceffary to impregnate the collar of leathers. Thefe were
always in a ftate of llrong compreffion, that they might
clofely grafp the pifton rod, and prevent all paffage of
air during the motion of the pifton. Whenever there¬
fore the cavities in the pifton rod come into the fituations
neceffary for connefting the receiver and barrel, this oil
is fqueezed into them, and choaks them up. Hence it
always happened that it w'as fome time after the ftroke
before the air could force its way round the pifton rod,
carrying with it the clammy oil which choaked up the
tube / m n ; and when the rare faction had proceeded a
certain length, the diminiftied elafticity of the air w as
not able to make its way through thefe obftru&ions.
The death of the ingenious author put a flop to the
improvements by which he hoped to remedy this defe£l,
and we have not heard that any other perfon has fince
attempted it. We have inferted it here, becaufe its
principle of conftruftion is not only very ingenious, but
entirely different from all others, and may furniffi very
ufeful hints to thofe who are much engaged in the con-
ftruftion of pneumatic engines. . _
In the 73d volume of the Philofophical Tranfaftions, ],y Haas>
Mr Tiberius Cavallo has given the defcription of anjmdHur-
air-pump contrived and executed by Mcflrs Haas andter-
Hurter, inftrument-makers in London, where thefe ar¬
tifts have revived Guericke’s method of opening the bar¬
rel-valve during the laft ftrokes of the pump by a force
a fling from without. We (hall infert fo much of this
defcription as relates to this diftinguifhing circumftance
of its conftruflion.
Fig. 29. reprefents a feflion of the bottom of the bar-p^ ^
rcl, where AA is the barrel and BB the bottom, which
has in its middle a hollow7 cylinder CCFF, projefting
about half an inch into the barrel at CC, and extending
a good way downwards to FF. The fpace between this
projeaion and the fides of the barrel is filled up by a
brafs ring DD, over the top of which is flrained a piece
of oiled filk EE, which performs the oflice of a valve,
covering the hole CC. But this hole is filled up by a
* piece
*53
P N E U M
Air-pump, piece of brafs, or rather an aflemblage of pieces fcrewed
- 1 together GGHHII. It confifts of three projefting fil¬
lets or (boulders GG, HH, II, which form two hollows
between them, and which are filled with rings of oiled
leather OO, PP, firmly fcrewed together. The extreme
fillets GG, II, are of equal diameter with the infide of
the cylinder, fo as to fill it exactly, and the whole Huf¬
fed with oiled leather, Aide up and down without allow¬
ing any air to pafs. The middle fillet HH is not fo
broad, but thicker. In the upper fillet GG there is
formed a {hallow di{h about of an inch deep and |
wide. This di{h is covered with a thin plate, pierced
with a grating like Mr Smeaton’s valve-plate. There
is a perforation VX along the axis of this piece, which
has a pafiage out at one fide H, through the middle fil¬
let. Oppofite to this paflage, and in the fide of the cy¬
linder CCFF, is a hole M, communicating with the
conduit pipe MN, which leads to the receiver. Into the
lower end of the perforation is fcrewed the pin KL, whofe
tail L paffes through the cap FF. The tail L is connefl¬
ed with a lever RO, moveable round the joint Q. This
lever is pufhed upwards by a fpring, and thus the whole
piece which we have been defcribing-is kept in contafl
with the flip of oiled filk or valve EE. This is the
ufual fituation of things.
Now fuppofe a void formed in the barrel by drawing
up the pifton j the elafticity of the air in the receiver, in
the pipe NM, and in the paffage XV, will prefs on the
great furface of the valve expofed through the grating,
will raife it, and the pump will perform precifely as Mr
Smeaton’s does. But fuppofe the rarefaflion to have
been fo long continued, that the air is no longer able to
raife the valve j this will be feen by the mercury riling
no more in the pump-gage. When this is perceived, the
operator muft prefs with his foot on the end R of the le¬
ver RQ. This draws down the pin KL, and with it the
whole hollow plug with its grated top. And thus, in-
flead of raifisg the valve from its plate, the plate is here
drawn down from the valve. The air now gets in with¬
out any obftruflion whatever, and the rarefaflion pro¬
ceeds as long as the pifton rifes. When it is at the top of
the barrel, the operator takes his foot from the lever, and
the fpring preffes up the plug again and {huts the valve.
The pifton rod paffes through a collar of leather, as in
Mr Smeaton’s pump, and the air is finally difcharged
through an outward valve in the top of the barrel.
Thefe parts have nothing peculiar in them.
This is an ingenious contrivance, fimilar to w'hat was
adapted by Guericke himfelf; and we have no doubt of
thefe pumps performing extremely well if carefully made:
and it feems not difficult to keep the plug perfeftly air¬
tight by fupplying plenty of oil to the leathers. We
cannot fay, however, with precifion what may be ex¬
pected from it, as no account has been given of its ef¬
fects befides what Mr Cavallo publifhed in Philofophica!
TranfaCtions 1783, where he only fays, that when it had
been long ufed, it had, in the courfe of fome experiments,
rarefied 6(70 times.
Aiming {till at the removing the obftruCtions to the
entry of the air from the receiver into the ban-els, Mr
Prince, an American, has conftruCted a pumjrln which
there is no valve or cock whatever between them. In
this pump the pifton rod paffes through a collar of lea¬
thers, and the air is finally difcharged through a valve,
as in the two laft. But we are chiefly to attend, in this
Vol. XVI. Part II.
. *54
by Prince,
A T I C S. 689
place, to the communication between the barrel and the Air-pump,
receiver. The barrel widens below into a fort of ciftern' y
ABCD (fig. 30.), communicating with the receiver by Fig. 3®*
the pipe EF. As foon, therefore, as the pifton gets into
this wider part, where there is a vacancy all round it, the
air of the receiver expands freely through the paffage
FEE into the barrel, in which the defcent of the pifton
had made a void. When the pifton is again drawn up,
as foon as it gets into the cylindric part of the barrel,
which it exaClly fills, it carries up the air before it, and
expels it by the top valve ; and, that this may be done
more completely, this valve opens into a fecond barrel
or air-pump whofe pifton is rifing at the fame time, and
therefore the valve of communication (which is the dif-
charging valve of the primary pump) opens with the
fame facility as Mr Smeaton’s pifton valve. While the
pifton is rifing, the air in the receiver expands into the
barrel $ and when the pifton defcends, the air in the
barrel again collapfes till the pifton gets again into the
ciftem, when the air paffes out, and fills the evacuated
barrel, to be expelled by the pifton as before.
No diftinft account has as yet b^en given of the per¬
formance of this pump. We only learn that great in¬
conveniences were experienced from the ofcillations of
the mercury in the gage. As foon as the pifton comes
into the ciftern, the air from the receiver immediately
nifties into the barrel, and the mercury {hoots up in
the gage, and gets into a ftate of ofcillation. The fub-
fequent rife of the pifton will frequently keep time with
the fecond ofcillation, and increafe it. The defcent of
the pifton produces a downward ofcillation, by allow¬
ing the air below it to collapfe; and, by improperly
timing the ftrokes, this ofcillation becomes fo great as
to make the mercury enter the pump. To prevent this,
and a greater irregularity of working as a condenfer,
valves were put in the pifton : but as thefe require force
to open them, the addition feemed rather to increafe the
evil, by rendering the ofcillations more fimultaneous with
the ordinary rate of working. If this could be got over, the
conftru&ion feems very promifing.
It appears, however, of very difficult execution. It has
many long, {lender, and crooked paffages, which muft be
drilled through broad plates of brafs, fome of them appear¬
ing fcarcely practicable. It is rare to find plates and other
pieces of brafs without air-holes, which it would be very
difficult to find out and to clofe 5 and it muft be very dif¬
ficult to clear it of obftruCtions ; fo that it appears rather
a fuggeftion of theory than a thing warranted by its ac¬
tual performance.
Mr Lavoifier, or fome of the naturalifts who were ky Lavoi-
occupied in concert with him in the inveftigation of the fier>
different fpecies of gas which are difengaged from bo¬
dies in the courfe of chemical operations, has contrived
an air-pump which has great appearance of fimplicity,
and, being very different from all others, deferves to be
taken notice of.
It confifts of two barrels /, tn, fig. 31. with folid pi- FiS- 3**
ftons kk. The pump-plate a b is pierced at its centre c
with a hole which branches towards each of the barrels,
as reprefented by c d, c e. Between the plate and the
barrels Aides another plate h /, pierced in the middle with
a branched boi&fdg, and near the ends with two holes
h h, i i, which go from its under fide to the ends. The
holes in thefe two plates are fo adjufted, that when the
plate h i is drawn fo far towards h that the hole i comes
4 S ' within
6 go
\>r piiTip. within the barrel m, the branch <2^ of the hole in the
middle plate coincides with the branch cd of the upper
plate, and the holes e, g are diut. Thus a communi¬
cation is eftablilhed between' the barrel / and the re¬
ceiver on the pump-plate, and between the barrel m and
the external air. In this fituation the barrel / will ex-
hauft, and jji will difcharge. When the pifton of /
is at its mouth, and that of in touches its bottom, the
Hiding plate is Ihifted over to the other fide, fo that m
communicates with the receiver through the paffage gd,
\ ec, and / communicates with the air by the paffages h h.
It is evident that this Hiding plate performs the office
of four cocks in a very beautiful and fimple manner, and
that if the piftons apply clofe to the ends of the barrels,
io as to expel the whole air, the pump will be perfeft.
It works, indeed, againft the whole preflure of the ex¬
ternal air. But this may be avoided by putting valves
on the holes h, t; and thefe can do no harm, becaufe
the air remaining in them never gets back into the bar¬
rel till the pifton be at the farther end, and the ex-
hauftion of that ftroke completed. But the beft work¬
men of London think that it will be incomparably more
difficult to execute this cock (for it is a cock of an un-
ufual form), in fuch a manner that it ffiall be air-tight
and yet move with tolerable eafe, and that it is much
more liable to wearing loofe than common cocks. No
accurate accounts have been received of its performance.
It muft be acknowiedged to be ingenious, and it may
fuggeft to an intelligent artift a method of combining
common conical cocks upon one axis fo as to anfwer the
. fame purpofes much more e He finally j for which reafon
we have inferted it here.
The laft improvement which we ffiall mention is that
publilhed by Mr Cuthbertfon philofophical inftrument-
maker in Amfterdam. His pump has given fuch evi¬
dences of its perfeflion, that we can hardly expefl or
wiffi for any thing more complete. But we muft be al¬
lowed to obferve, beforehand, that the fame conftruc-
tion was invented, and, in part, executed before the
end of I779> by Dr Daniel Rutherford, now profeffor
of botany in the univerfity of Edinburgh, who w*as at
that time engaged in experiments on the produflion of
air during the combuftion of bodies in contafl with
nitre, and who w^as vaftly defirous of procuring a more
complete abftraflion of pure aerial matter than could be
etfefled by Mr Smeaton’s pump. The compiler of this,
article had then an opportunity of perufmg the Doffor’s
differtation on this fubjeft, which was read in the Phi¬
lofophical Society of Edinburgh. In this diflertation
the Doflor appears fully apprifed of the exiftence of pure
vital air in the nitrous acid, as its chief ingredient, and
as the caufe of its moft remarkable phenomena, and to
want but a ftep to the difcoveries which have ennobled
the name of Mr Lavoifier. He was particularly anxious
to obtain apart this diftinguiffiing ingredient in its com-
pofition, and, for this purpofe, to abftradl completely
from the vefi'el in which he fubje&ed it to examination,
every particle of elaftic matter. The writer of this ar¬
ticle propofed to him to cover the bottom of Mr Smea¬
ton’s pifton with fome clammy matter, which ffiould
PNEUMATICS.
is*
■and by
Cuthbert-
fon.
take hold of the bottom valve, and/c/7 it when the pi- Air-pnmn,
fton was drawn up. A few days after, the Doeftor
fhowed him a drawing of a pump, having a conical me¬
tal valve in the bottom, furniffied with a long flender
wire, Hiding in the infide of the pifton-rod with a gentle
fridion, lufficient for lifting the valve, and lecured
againft all chance of failure by a fpring a-top, which
took hold of a notch in the infide of the pifton-rod about
a quarter of an inch from the lower end, fo as certainly
to lift the valve during the laft quarter of an inch of the
pibon’s motion. Being an excellent mechanic, he had
executed a valve on this principle, and w?as fully fatis-
fied with its performance. But having already confirm¬
ed his doctrines refipeding the nitrous acid by incontro¬
vertible experiments, his wiffies to improve the air-pump "
loft their incitement, and he thought no more of it 5 and
not long after this, the ardour of the philofophers of the
i eylerian Society at Haerlem and Amfterdam excited the
efforts of Mr Cuthbertfon, their inftrument-maker, to the
fame purpofe, and produced the moft perfed air-pump that
has yet appeared. We ffiall give a defcription of it, and an
account of its performance, in the inventor’s own words.
CuTHBERTSON's Air-Pump.
On Plate CCCCXXVII. fig. 32. is a perfpedive view 157
ot this pump, with its two principal gages fcrewed into Fig. 32.
their places. Thefe need not be ufed together, except
in cafes where the utmoft exadnefs is required. In com¬
mon experiments one of them is removed, and a ftop-
crew put in its place. When the pear-gage is ufed, a
Imall round plate, on which the receiver may ftand
muft be firft fcrewed into the hole at A j but this hole
is flopped on other occafions with a fcrew. When all
the three gages are ufed, and the receiver is exhaufted
tlm ftop-fcrew B, at the bottom of the pump, muft be’
unlcrewed, to admit the air into the receiver ; but when
they are not all ufed, either of the other ftop-fcrews will
anlwer this purpofe.
Fi|- 33- reprefeQts a crofs-bar for preventing the bar-F-
rels from being ffiaken by working the pump or by any g‘ 33*
accident. Its place in fig. 32. is reprefented by the dot¬
ted lines. It is confined in its place, and kept clofe
down on the barrels, by two Hips of wood NN, which
muft be drawn out, as well as the fcrews 00, when the
pump is to be taken afunder.
Plate CCCCXXVIII. exhibits a fedion of all the
working parts of the pump, except the wheel and rack,
m which there is nothing uncommon.
Flg* 34- is a fedion of one of the barrels, with all its
internal parts •, and fig. 35. 36. 37. and 38. are differ¬
ent parts of the pifton, proportioned to the fize of the
barrel (a) and to one another.
In fig. 34. CD reprefents the barrel, F the collar ofFff. 34.
leathers, G a hollow cylindrical veffel to contain oil, R fa '
is alfo an oil-veffel to receive the oil which is drawn
along with the air, through the hole a a, when the pi¬
fton is drawn upwards; and, when this is full, the oil is
carried over with the air, along the tube T, into the
oil-veffel G. cc is a wire which is driven upwards from
the
(a) The pifton and barrel are 1.65 inches in diameter, in proportion to which the fcale is drawn.
36. 37, and 38. are, however, of double fize.
Fi§ures 3S'
P N £ U M
Air-pump, the hole a a hy the paflage of the air j and as foon as
this has efcaped, it falls down again by its own weight,
fhuts up the bole, and prevents all return of the air into
the barrel. At d d are fixed two pieces of brafs, to
keep, the wire c c in a vertical direction, that it tnay ac¬
curately (hut the hole. H is a cylindrical wire or rod
which .carries the pifton I, and is made hollow to receive
a long wire gg, which opens and fhuts the hole L ;
and on the other end of the wire O is fcrewed a nut,
which, by flopping in the narroweft part of the hole,
prevents the wire from being driven up too far. This
wire and fcrew are more clearly feen in fig. 35. and 39. j
they Aide in a collar of leather ?• r, fig. 35. and 38* in
the middle piece of the piflon. Fig. 37. and 38. are the
two mean parts which compofe the pifton, and, when
the pieces 36. and 39. are added to it, the whole is re-
prefented by fig. 35. Fig. 38. is a piece of brafs of a
conical form,- wTith a fhoulder at the bottom. A long
hollow fcrew is cut in it, about two-thirds of its length,
and the remainder of the hole, in which there is no
fcrew, is of about the fami diameter with the fcrewed
part, except a thin plate at the end, which is of a width
exactly equal to the thicknefs of gg. That part of the
infide of the conical brafs in which no thread is cut, is
filled with oiled leathers with holes through which gg
can Hide ftiffly. There is alfo a male fcrew with a hole
in it, fitted to gg, ferving to comprefs the leathers r r.
In fig. 37. a a a a is the outfide of the pifton, the infide
of which is turned fo as exactly to fit the outfide of
%• 38. b b are round leathers about 60 in number,
c c is a circular piece of brafs of the fize of the leathers,
and dd is a. fcrew ferving to comprefs them. The fcrew
at the end of fig. 36. is made to fit the fcrew in fig. 38.
Now if fig. 39. be puftied into fig. 38. this into fig. 37.
and fig. 36. be fcrewed into the end of fig. 38. thefe will
compofe the whole of the pifton, as re prefen ted in
fig. 34. H in fig. 34. reprefents the fame part as H in
fig. 35. and is that to which the rack is fixed. If,
therefore, this be drawn upwards, it will caufe fig. 38.
to ftiut clofe into fig. 37. and drive out the air above it $
and when it is puftied downward, it will open as far as
the ftioulder a a will permit, and fuffer air to pafs
through. AA, fig. 40. is the receiver plate, BB is a
long fquare piece of brafs, fcrewed into the under fide
of the plate, through which a hole is drilled correfpond-
ing to that in the centre of the receiver-plates and with
three female fcrews b, b, c.
The rarefaction of the air in the receiver is effeCted
as follows. Suppofe the pifton. at the bottom of the
barrel. The infide of the barrel, from the top of the pi¬
fton to a, fig. 34. contains common air. When the rod is
drawn up, the upper part of the pifton flicks fall in the
barrel till the conical part connected with the rod fliuts
the conical hole, and its ftioulder applies clofe to its bot¬
tom. The pifton is now (hut, and therefore the whole
is drawn up by the rack-work, driving the air before it
through the hole a c, into the oil-veffel at R, arid out
into the room by the tube T. The pifton will then be
at the top of the barrel at d, and the wire gg will ftand
nearly as reprefented in the figure juft raifed from the
hole L, and prevented from rifing higher by the nut O.
During this motion the air will expand in the receiver,
and come along the bent tube m into the barrel. Thus
the barrel will be filled with air, which, as the pifton
fifes, will be rarefied in proportion as the capacity of
Fig. 49.
34-
A T 1 C' S. 69 r
the receiver, pipes, and barrel, is to the barrel alone. Air-pump1
When the pifton is moved down again by the rack-work, v
it will force the conical part fig. 38. out of the hollow
part fig. 37. as far as the ftioulders a a ; fig. 35. will
reft on a a fig. 37. which will then be fo far open as
to pennit the air to pafs freely through it, while at the
fame time the end of gg is forced againft the top of the
hole, and (huts it in order to prevent any air from re¬
turning into the receiver. Thus the pifton, moving
downwards, fuffers the air to pafs out between the fides
of fig. 37. and 38. j and, when it is at the bottom of the
barrel, will have the column of air above it 5 and, con-
fequently, when drawn upwards it will (hut, and drive
out this air, and, by opening the hole L at the fame
time, will give a free paffage to more air from the re¬
ceiver. This procefs being continued, the air of the re¬
ceiver will be rarefied as far as its expanfve power will
permit. For in this machine there are no valves to be
forced open by the elafticity of the air in the receiver,
which at laft it is unable to effeft. There is therefore
nothing to prevent the air from expanding to its utmoft
degree.
It may be fufpe&ed here, that as the air muft efcape
through the difcharging paffage a c, fig. 34. againft
the preffure of a column of oil and the weight of the
wire, there will remain in this pafiage a quantity of
air of confiderable denfity, which will expand again
into the barrel during the defcent of the pifton, and
thus put a flop to the progrefs of rarefaction. This is
the cafe in Mr Smeaton’s pump, and all w'hich have
valves in the pifton. But it is the peculiar excellency
of this pump, that whatever be the denfity of the air
remaining in ac, the rarefaction will ftill go on. It is
worth while to be perfectly convinced of this. Let us
fuppofe that the air contained in o c is Part °f ih®
common air which would fill the barrel, and that the
capacity of the barrel is equal to that of the receiver
and paffages, and that the air in the receiver and bar¬
rel is of the fame denfity, the pifton being at the bot¬
tom of the barrel: The barrel will therefore contain
t^§o- parts of its natural quantity, and the receiver
Now let the pifton be drawn up. No air will
be difcharged at a c, becaufe it will contain the whole
air wFich was in the barrel, and which has now col-
lapfed into its ordinary bulk. But this does not in the
leaft hinder the air^of the receiver from expanding into
the barrel, and dxffufing itfelf equally between both.
Each will now contain ToW their ordinary quantity
when the pifton is at the top, and a c will contain
as before, or Now pufh down the pifton. The
hole L is inftantly (hut, and the air ih a c expands in¬
to the barrel, and the barrel now contains ts4o- When
the pifton has reached the bottom, let it be again draw-n
up. There will be toW difcharged through c, and
the air in the receiver will again be equally diftributed
between it and the barrel. Therefore the receiver will
now contain . When the pifton reaches the bot
IOOO
tom, there will be in tbe barrel. When again
1000 0
2*
drawn up to the top, there will be —— difcharged,,
r r 1000 0
and the receiver will contain -----: and when the piftoft
1,000
4 S i reaches
692 P N E U M
Air-pump.
^ v > reaches the bottom, there will be  At the
IOOO
• o ^
next ftroke the receiver will contain only •———, &c.
IOOO
&c.
Thus it appears, that notwithftanding the t-Jwhich
always expands back again out of the hole a c into the
barrel, the rarity of the air in the receiver will be
doubled at every ifroke. There is therefore no need
of a fubfidiary air-pump at c, as in the American air-
pump, and in the Swediih attempt to improve Smea-
ton’s.
In ufmg this air-pump no particular direftions are ne-
ceffary, nor is any peculiar care neceffary for keeping it
in order, except that the oil-veffel A be always kept
about half full of oil. When the pump has flood long
wishout being ufed, it will be proper to draw a table-
ipoonful of olive-oil through it, by pouring it into the
hole in the middle of the receiver-plate when the pi-
iion is at the bottom of the barrel. Then by working
ilie pilfon, the oil will be drawn through all the parts of
the pump, and the furplus will be driven through the
tube T into the oil-veflel G. Near the top of the pi-
flon-rod at H there is a hole which lets fome oil into the
iniide of the rod, which gets at the collar of leathers
r /•, and keeps the wire gg air-tight.
When the pump is ufed for condenfation at the fame
time that it rarefies, or feparately, the piece containing
the bent tube T muft be removed, and fig. 41. put into
Fig- 41, its place, and fixed by its fcrews. Fig. 41. as drawn in
the plate, is intended for a double-barrelled pump. But
for a fingle barrel only one piece is ufed, reprefented by
baa, the double piece being cut oft' at the dotted line
a <7. In this piece is a female fcrew to receive the end
of a long brafs tube, to which a bladder (if fufficient for
the experiment of condenfaticn), or a glafs, properly fe-
cured for this purpofe, muft be fcrewed. Then the air
which is abftrafted from the receiver on the pump-plate
will be forced into the bladder or glafs. But if the
pump be double, the apparatus fig. 41. is ufed, and the
long brafs tube fcrewed on at c.
Fig. 42. big. 42. and 43. reprefent the two gages, wdrich will
and 43. kg fufficiently explained afterwards. Fig. 42. is fcrewed
into c b, or into the fcrew at the other end of c fig. 40.
and fig. 43. into the fcrew ab fig. ^o.
If it be ufed as a fingle pump, either to rarefy or coh-
denfe, the fcrew K, which fallens the rack to the pifton-
rod H, muft be taken out. Then turning the winch till
H is deprefled as low as poftible, the machine will be
fitted to exhauft as a fingle pump $ and if it be required
to condenfe, the direction in N° 8. muft be obferved
with regard to the tube T, and fig. 41.
“ I took (fays Mr Cuthbertfon) two barometer-tubes
of an equal bore with that fixed to the pump. Thefe
were filled with mercury four times boiled. They were,
then compared, and flood exa&ly at the fame height.
The mercury in one of them was boiled in it four times
more, without making any change in their height j they
were therefore judged very perfect. One of thefe was
immerfed in the ciftern of the pump-gage, and faftened
in a pofitien parallel to it, and a Aiding fcale of one inch
was attached to it. This fcale, when the gage is ufed,
muft have its upper edge fet equal with the furface of
the mercury in the boiled tube after exhauftion, and the
A T I C S.
difference between the height of the mercury in tins and Afr-pumpi
in the other barometer tube may be obferved to the
of an inch j and being clofe together, no error
arifes from their not being exa£!ly vertical, if they are
only parallel. This gage will be better underftood by
infpe&ing fig. 43.
“ I uled a lecond gage, which I fhall call a double
fyphon. See fig. 42. This was alfo prepared with the
utmoft care. 1 had a fcale for meafuring the difference
between the height of the columns in the two legs. It
was an inch long, and divided as the former, and kept
in a truly vertical pofition by fufpending it from a point
with a weight hung to it, as reprelented in the figure.
Upon comparing thefe two gages, I always found them
to indicate the lame degree of rarefaction. I alfo ufed
a pear-gage, though the moft imperfect of all, in order
to repeat the curious experiments of Mr Nairne and.
others.”
When experiments require the utmoft rarefying-
power of the pump, the receiver muft not be placed
on leather, either oiled or foaked in water, as is ufually
done. The pump-plate and the edge of the receiver
muft be ground very Aat and true, and this with very,
fine emery, that no roughnefs may remain. The plate
of the pump muft then be wiped very clean and very,
dry, and the receiver rubbed with a warm cloth till, it
become eledtrical. The receiver being now fet on the
plate, hog’s lard, either alone or mixed writh a little
oil, which has been cleared of wTater by boiling, mull
be fmeared round its outfide edge. In this condition
the pump wall rarefy its utmoft, and what ftill remains,
in the receiver wift be permanent air. Or a little of this
compofition may be thinly fmeared on the pump-plate j.
this will prevent all rilk of fcratching it with the edge
of the receiver. Leather of very uniform thicknels,
long dried before a fire, and wrell foaked in this com¬
pofition, which muft be cleared of all water by the
firft boiling, wall anfwe.r very well, and is expeditious,
when receivers are to be frequently ihifted. Other
leathers ftiould be at hand foaked in a compofition con¬
taining a little rolin. This gives it a clamminefs which
renders it impermeable to air, and is very proper at all
joints of the pump, and all apparatus for pneumatic ex¬
periments. As it is impoflible to render the pear-gage
as dry as other parts of the apparatus, there will be-
generally fome variation between this and the other
gages.
When it is only intended to ftuwv the utmoft power
of the pump, wdthout intending to afeertain the qua¬
lity of the refiduum, the receiver may be fet on wet
leather. If, in this condition, the air be rarefied as far
as pofllble, the fyphon and barometer gage will indi¬
cate a lefs degree of rarefadtion than in the former ex¬
periments. But wdien the air is let in again, the pear-
gage will point out a rarefaction fome thoufands of
times greater than it did before. If the true quality
of permanent air after exhauftion be required, the pear-
gage will be neareft the truth : for when the air is
rarefied to a certain degree, the moiftened leather emits
an expanfible fiuid, which, filling the receiver, forces
out the permanent air; and the two firft gages indicate
a degree of exhauftion which relates to the whole ela-
ftic matter remaining in the receiver, viz. to the ex-
panfible fluid together with the permanent air; whereas
the pear-gage points out the degree of exhauftion, with
relation
PNEUMATICS.
<593
AiY-]»fbp. relation to the permanent air alone, which remains in
' r ' the receiver j for by the preffure of the air admitted into
the receiver, the elaftic vapour is reduced to its former
balk, which is imperceptible.
Many bodies emit this elaftic fluid when the preflure
of the air is much diminifhed $ a piece of leather, in its
ordinary damp ftate, about an inch fquare, or a bit of
green or dry wood, will fupply this for a great while.
When fuch fluids have been generated in any expe¬
riments, the pump muft be carefully cleared of them,
for they remain not only in the receiver, but in the
barrels and paffages, and will again expand when the
exhauftion has been carried far.
The beft method of clearing the pump is to take a
▼ery large receiver, and, uling every precaution to ex-
hauft it as far as poflible. Then the expaaftble matter
lurking in the barrels and paffes will be diffufed through
the receiver alfo, or will be carried off along with its
air. It will be as much rarer than it was before, as the
aSgreg'ate capacity of the receiver barrels and paffes is
larger than that of the two laft.
The performance of the pump may be judged of from
the four following experiments.
The two gages being fcrewed into their places, and
the hole in the receiver-plate Unit up, the pump was
made to exhauft as far as it could. The mercury in
the legs of the fyphon was only of an inch out of
the level, and that in the boiled barometer-tube ^ of
an inch higher than in the one fcrewed to the pump.
A ftandard barometer then flood at 30 inches, and
therefore the pump rarefied the permanent air 1200
times. This is twice as much as Mr Nairne found
Mr Smeaton’s do in its beft ftate. Mr Cavallo feems
dilpofed to give a favourable (while we muft fuppofe
it a juft) account of Haas and Hurter’s pump, and
it appears never to have exceeded 600 times. Mr
Cuthbertfon has often found the mercury within T^-_
of an inch of the level in the fyphon-gage, indicating a
rarefaction of 3000.
To one end of a glafs tube, 2 inches diameter and
30 inches long, was fitted a brafs cap and collar of
leather, through which a wire wras inferted, reaching
about two inches within the tube. This was connected
with the conductor of an eleCtric machine. The other
end was ground flat and fet on the pump plate. When
the gages indicated a rarefaCtion of 3000, the light be¬
came fteady and uniform, of a pale colour, though a
little tinged with purple; at 600 the light was of a
pale duflcy white ; when 1200 it difappeared in the
middle of the tube, and the tube conducted fo well
that the prime conductor only gave fparks fo faint and
fliort as to be fcarcely perceptible. After taking off
the tube, and making it as dry as pofiible, it was again
connected with the conductor, which was giving fparks
two inches long. When the air in it was rarefied ten
times, the fparks were of the fame length. Sometimes
a pencil of light darted along the tube. When the
rarefaCtion was 20, the fpark did not exceed an inch,
and light ftreamed the whole length of the tube. When
the rarefaCtion was 30, the fparks were half an inch,
and the light rulhed along the tube in great ftreams.
When the rarefaCtion was too, the fparks were about J-
long, and the light filled the tube in an uninterrupted
body. When 300, the appearances were as before.
When 600, tue fparks were Tj, and the light was of
a faint white colour in the middle, but tinged with Air-pump,
purple toward the ends. When 1200, the light was —v—
hardly perceptible in the middle, and was much fainter
at the ends than before, but ftill ruddy. When 1400,
which was the moft the pump could produce, fix inches
of the middle of the tube were quite dark, and the
ends free of any tinge of red, and the fparks did not
exceed ^ of an inch.
i5$
We truft that our readers will not be difpleafed with The beft
the preceding hiftory of the air-pump. The occalional irnProve*
miormation which it gives will be of great ule to every air_
perfon much engaged in pneumatic experiments, and pump have
help him in the contrivance and conftruCtion of the ne- been made
ceffary apparatus. in Biitam.
We may be indulged in one remark, that although
this noble inftrument originated in Germany, all its im¬
provements were made in this kingdom, iioth the. me¬
chanical and pneumatical principles of Mr Boyle’s con¬
ftruCtion were extremely different from the German,, and,
in refpeCl of expedition and conveniency, much fuperior.
The double barrel and gage by Hawkelbee were capital
improvements, and on principle and Mr Smeaton’s
method of making the pifton work in rarefied air made
a complete change in the whole procefs.
Aided by this machine, we can make experiments Utility of
eftablilhing and illuftrating the gravity and elafticity of the air-
the air, in a much more perfpicuous manner than could PumP*
be done by the fpontaneous- phenomena of nature.
It allows us in the firft place to fhow the materiality Experi-
of air in a very diftinC! manner. Bodies cannot move mei5ts to
about in the atmofphere without difplacing it. Thisthis
requires force ; and the refiftance of the air always di- U 1 ^
minilhes the velocity of bodies moving in it. A heavy
body therefore has the velocity of its fall dimini ftied ;
and if the quantity of air difplaced be very great, the
diminution wall be very confiderable. This is the rea-
fon why light bodies, fuch as feathers, fall very {lowly.
Their moving force is very fmall, and can therefore
difplace a great quantity of air only with a very fmall
velocity. But if the fame body be dropped in vacuay
when there is no air to be difplaced, it falls with the
whole velocity competent to its gravity. -Fig. 44. Plate
reprefents an apparatus by which a guinea and a downy cefcxxix.
feather are dropped at the fame inftant, by opening fag‘44'
the forceps which holds them by means of the flip-
wire in the top of the receiver. If this be done after
the air has been pumped out, the guinea and the fea¬
ther will be obferved to reach the bottom at the fame
inftant.
Fig. 45. reprefents another apparatus for {bowing the 161
fame thing. It confifts of two fets of brafs vanes put F!g-45-
in feparate axles, in the manner of windmill fails. One
fet has their edges placed in the dire&ion of their
whirling motion, that is, in a plane to which the axis
is perpendicular. The planes of the other fet pafs
through the axis, and they are therefore trimmed fo as
direftly to front the air through which they move.
Two fprings aft upon pins projeding from the axis;
and their fcrength or tenfions are fo adjufted, that when
they are difengaged in vacuo, the two fets continue in
motion .equally long. If they are difengaged. in the
air, the vanes which beat the air with their planes will
flop long before thofe which cut it edgewife.
We can now abftrad the air moft completely from ifo
a
PNEUMATICS.
694
‘Air-pump. a dry veiTel, fo as to know the precifc weight of the
v air which filled it. The firlt experiment we have of
this kind, done with accuracy, is that of Dr Hooke,
February 10. 1664, when he found 114 pints of air to
weigh 945 grains. One pint of water was 8T7T ounces.
This gives for the fpecific gravity of air -gA^- very
163 nearly.
The effect Since we are thus immerfed in a gravitating fluid, it
the^wdcrh ^0^0W3> ^iat every body preponderates only with the
©f bodies 1 e^ce^s bs own weight above that of the air which it
immerfed difplaces; for every body lofes by this immeriion the
m it. weight df the difplaced air. A cubic foot lofes about
521 grains m frofty weather. We fee balloons even
rife in the air, as a piece of cork rifes in water. A
mafs of water which really contains 850 pounds will
load the fcale of a balance with 849 only, and will be
balanced by about 849^ pounds of brafs. This is e-
vinced by a very pretty experiment, reprefented in
Fig. 46. 4.6, A fmall beam is fufpended within a receiver.
1 o one end of the beam is appended a thin glafs or
copper ball, clofe in every part. This is balanced by
a fmall piece of lead hung on the other arm. As the
air is pumped out of the receiver, the ball will gradu¬
ally preponderate, and will regain its equilibrium when
the air is re-admitted.
164 Some naturalifls have propofed, and a&ually ufed, a
large globe of light make, fufpended at a beam, for a
barometer. If its capacity be a cubic foot, grains
will indicate the fame change that is indicated by
of an inch of an ordinary barometer. But a veflel of
this fize will load a balance too much to leave it fuffi-
ciently fenfible to fmall changes of denfity. Befides,
it is affefted by heat and cold, and would require a
very troublefome equation to corre£t their effe&s.
165 It may perhaps be worth while to attend to this in
buying and felling precious commodities ; fuch as pearls,
diamonds, filk, and fome drugs. As they are generally
fold by brafs or leaden weights, the buyer will have
fome advantage when the air is heavy and the barome¬
ter high. On the other hand, he will have the advan¬
tage in buying gold and mercury when the air is light.
It is needlefs to confine this obfervation to precious
commodities, for the advantage is the fame in all in
proportion to their levity.
166 There is a cafe in which this obfervation is of confe-
quence to the philofopher: we mean the meafuring of
time by pendulums. As the accelerating force on a
pendulum is not its whole weight, but the excefs of its
weight over that of the difplaced air, it follows that a
pendulum will vibrate more flowly in the air than in va¬
cuo. A pendulum compofed of lead, iron, and brafs,
may be about 8400 times heavier than the air which
it difplaces when the barometer is at 30 inches and
the thermometer at 3 2°, and the accelerating force will
be diminithed about r-y-g-s-o* This will caufe a fecond
pendulum to make about five vibrations lefs in a day
than it would do in vacuo. In order therefore to de¬
duce the accelerative power of gravity from the length
of a pendulum vibrating in the air, we mult make an
allowance of o/,.i7, or Any of a fecond, per day for
every inch that the barometer Hands lower than 30
inches. But we muft alfo note the temperature of the
air ; becaufe when the air is warm it is lefs denfe when
fupporting by its elafticify the fame weight of atmo-
fphere, and we mult know how much its cfen&y is dl- Ah-ptnrfr,
minilhed by an increafe of temperature. The correction
is Itill more complicated ; for the change of denfity af-
fe&s the refiftance of the air, and this affeCts the time
of the vibration, and this by a law that is not yet well
afcertained. As far as we can determine from any ex¬
periments that have been made, it appears that the
change arifing from the altered refiltance takes off about
T of the change produced by the altered denfity, and
that a lecond pendulum makes but three vibrations a-
day more in vacuo than in the open air. This is a very
unexpected refult: but it muft be owned that the expe¬
riments have neither been numerous nor very nicely
made.
_ The air-pump alfo allows us to fhow the effeCts of the
air’s preffure in a great number of amufing and inftruc-
tive phenomena. ,
When the air is abftraCted from the receiver, it isExperi-
ftrongly preffed to the pump-plate by the incumbent ments to
atmofphere, and it fupports this great preffure in con-^owth|
fequence of its circular form. Being equally compreffed the tir’s'
on all tides, there is no place where it Ihould give waypreflure.
rather than another; but if it be thin, and not very
round, which is fometimes the cafe, it will be crulhed
to pieces. If we take a fquare thin phial, and apply
an exhaufting fyringe to its mouth, it will not fail be¬
ing crufhed.
As the operation of pumping is fomething like fuck¬
ing, many of thefe phenomena are in common difcourfe
afcribed to fuCtion, a word much abufed 5 and this
abufe milleads the mind exceedingly in its contemplation
of natural phenomena. Nothing is more ufual than to
fpeak of the fuCtion of a fyringe, the fuClion and draught
of a chimney, &c. The following experiment puts the
true caufe of the ftrong adhefion of the receiver beyond
a doubt.
Place a fmall receiver or cupping-glafs on the pump-
plate without covering the central hole, as reprefented
in fig. 47. and cover it with a larger receiver. Exhauft Fig. 47*
the air from it; then admit it as fuddenly as poflible.
The outer receiver, which after the rarefaCtion adhered
ftrongly to the plate, is now loofe, and the cupping-
glafs will be found flicking faff to it. While the rare-
faflion was going on, the air in the fmall receiver alfo
expanded, efcaped from it, and was abftrafled by the
pump. When the external air was fuddenly admitted,
it preffed on the fmall receiver, and forced it down to
the plate, and thus fhut up all entry. The fmall re¬
ceiver muft now adhere 5 and there can be no fudlion,
for the pipe of the pump was on the outfide of the cup¬
ping-glafs.
This experiment fometimes does not fucceed, becaufe
the air fometimes finds a paffage under the brim of the
cupping-glafs. But if the cupping-glafs be preffed
down by the hand on the greafy leather or plate, every
thing will be made fmooth, and the glafs will be fo little
railed by the expanfion of its air during the pumping, that
it will inftantly clap clofe when the air is re-admitted.
In like manner, if a thin fquare phial be furnifhed with l6^
a valve, opening from within, but (hutting when preffed
from without, and if this phial be put under a receiver,
and the air be abftrafted from the receiver, the air in the
phial will expand during the rarefatflion, will efcape
through the valve, and be at laft in a very rarefied ftate
within
4
Fig. 49.
170
Fig. S°»
P N E U M
Air-pump- within the pMal. If the air be now admitted into the
receiver, it will prefs on the flat fldes of the included
phial and crufli it to pieces. See fig. 48.
If a piece of wet ox-bladder be laid over the top of
a receiver whole orifice is about four inches wide, and
the air be exhaufled from within it, the incumbent at-
mofphere will prefs down the bladder into a hollow
form, and then burft it inward with a prodigious node.
See fig. 49. Or if a piece of thin flat glafs be laid over
the receiver, with an oiled leather between them to make
the junfture air-tight, the glafs will be broken down¬
wards. This muft be done with caution, becaufe the
pieces of glafs fometimes fly about with great force.
If there be formed two hemifpherical cups of brafs,
with very flat thick brims, and one of them be fitted
with a neck and ftopcock, as reprefented by fig. 50. the
air may be abftrafted from them by fcrewing the neck
into the hole in the pump-plate. To prevent the infinu-
ation of air, a ring of oiled leather may be put between
the rims. Now unfcrew the fphere from the pump, and
fix hooks to each, and fufpend them from a ftrong nail,
and hang a fcale to the loweft. It will require a confi-
derable w?eight to feparate them; namely, about 15
pounds for every fquare inch of the great circle of the
fphere. If this be four inches diameter, it will require
near 190 pounds. This pretty experiment was firft made
by Otto Guericke, and on a very great fcale. His fphere
was of a large fize, and when exhaufted the hemifpheres
could not be drawn afunder by 20 horles. It was exhi¬
bited, along with many others equally curious and mag¬
nificent, to the emperor of Germany and his court, at
the breaking up of the diet of Ratifbori in 1654*
If the loaded fyringe mentioned in N° 16. be fufpend-
ed by its pifton from the hook in the top plate of the re¬
ceiver, as in fig. 51. and the air be abltradled by the
pump, the fyringe will gradually defcend (becaufe the
elafticity of the air, which formerly balanced the pref-
fure of the atmofphere, is now diminifhed by its expan-
fion, and is therefore no longer able to prefs the fyringe
to the pifton), and it wall at laft drop off. If the air be
admitted before this happens, the fyringe will immedi¬
ately rife again.
Screw a ftiort brafs pipe into the neck of a tranfpor-
ter, N° 107. on which is fet a tall receiver, and immerfe
it into a ciftern of water. On opening the cock the pref-
fure of the air on the furface of the water in the ciftern
will force it up through the pipe, and caufe it to fpout
into the receiver with a ftrong jet, becaufe there is no
air within to balance by its elafticity the preffure of the
atmofphere. See fig. 52.
It is in the fame way that the gage of the air-pump
performs its office. The preffure of the atmofphere raif-
es the mercury in the gage till the weight of the mercu¬
ry, together with the remaining elafticity of the air in
the receiver, are in equilibrio with the whole preffure of
the atmofphere: therefore the height and weight of the
mercury in the gage is the excefs of the weight of the
atmofpheie above the elafticity of the included air ; and
the deficiency of this height from that of the mercury in
the Toricellian tube is the meafure of this remaining ela¬
fticity.
If a Toricellian tube be put under a tall receiver, as
fhown in fig. 53. and the air be exhaufted, the mercury
in the tube will defcend while that in the gage will rife j
and the fum of their heights will always be the fame?
171
Fig. 51-
Fig. 52-
>73
By means
of this
preflare the
gage of an
air-pump
ads.
-. *74
*g. 53*
A T I C S. _ 695
that is, equal to the height in an ordinary barometer. Air-pump.^
The height of the mercury in the receiver is the effedt' v ’
and meafure of the remaining elafticity of the included
air, and the height in the pump-gage is the unbalanced
preffure of the atmofphere. This is a very inftru&ive
experiment, perfectly fimilar to Mr Auzout’s, mention¬
ed in N° 34. and completely eftablifties and iliuftrates
the wffiole dodtrine of atmofpheric preffure. 175
We get a fimilar illuftration and confirmation (if fuch Water rifts
a thing be new needed) of the caufe of the rife of water10 P1103!*.
in pumps, by lerewing a fyringe into the top plate of a
receiver, which fyringe has a ftiort glafs pipe plunging
into a fmall cup of water. See fig. 54. When the pif- fig. S4.
ton-rod is drawn up, the water rites in the glafs pipe, as
in any other pump, of which this is a miniature repre-
fentation. But if the air has been previoufly exhaufted
from the receiver, there is nothing to prefs on the wa¬
ter in the little jar *, and it will not rife in the glafs
pipe though the pifton of the fyringe be drawn to the
top. ’ _ .... I75
Analogous to the rife of water in pumps is its rife andon^ moves
motion in fyphons. Suppofe a pipe ABCD, fig. 55.^ ^ ^ ‘
bent at right angles at B and C, and having its two ends ^
immerfed in the citterns of water A and D. Let the
leg CD be longer than the leg BA, and let the whole
be full of water. The water is preffed upwards at A
with a force equal to the weight of the column of air E
A reaching to the top of the atmofphere 5 but it is pref¬
fed downwards by the weight of the column of water B
A. The water at E is preffed downwards by the weight
of the column CD, and upwards by the weight of the
column of air FD reaching to the top of the atmofphere.
The two columns of air differ very little in their weight,
and may without any fenfible error be confidered as e-
qual. Therefore there is a fuperiority of preffure down¬
wards at D, and the water will flow out there. The
preffure of the air will raife the water in the leg AB,
and thus the ftream will be kept up till the veffel A is
emptied as low as the orifice of the leg BA, provided
the height of AB is not greater than what the preffure
of the atmofphere can balance, that is, does not exceed
32 or 33 feet for water, 30 inches for mercury, &c.
A fyphon then will always run from that veffel whofe
furface is higheft; the form of the pipe is indifferent,
becaufe the hydroftatical preffures depend on the verti¬
cal height only. It muft be filled with water by fome
other contrivance, fuch as a funnel, or a pump appli¬
ed a-top ; and the funnel muft be flopped up, otherwife
the air would get in, and the water would fall in both
legs.
If the fyphon have equal legs, as in fig. 56. and be
turned up at the ends, it will remain full of water, and '
be ready for ule. It need only be dipped into any vef¬
fel of water, and the water will then flow out at the other
end of the fyphon. This is called the Wirtemberg fy¬
phon, and is reprefented in fig. 56. Syphons will after¬
wards be confidered more minutely under the title of
PNEUMAT1CAL Engines, at the end of this article.
What is called the fyphon fountain, conftrudled on this The fypHon
principle, is fhown in fig. 57. where AB is a tall recei-^.unta’n*
ver, ftanding in a wide bafon DE, which is fupported.tl^'
on the pedeftal H by the hollow pillar EG. In the cen¬
tre of the receiver is a jet pipe C, and in the top a ground
ftopper A. Near the bafe of the pillar is a cock N, and,
in the pedeftal is another cock O.
YPjX'
PNEUMATICS.
179
Manner of
Kg- 57-
Fill the bafon DE with water within half an inch of
the brim. Then pour in water at the top of the recei¬
ver (the cock N being fhut) till it is about half full, and
then put in the ftopper. A little water will run out into
the veffel DE. But before it runs over, open the cock
N, and the water will run into the ciftern H ; and by
the time that the pipe C appears above water, a jet will
rife from it, and continue as long as water is fupplied
from the bafon EE. The paffage into the bafe cillern
may be fo tempered by the cock N that the -water with¬
in the receiver lhall keep at the fame height, and what
runs into the bafe may be received from the cock O in¬
to another veffel, and returned into EE, to keep up the
ftream.
This pretty philofophical toy may be conftrufted in
its confouc-following manner. BB, fig. 58- is the ferrii or cap
operation iut° which the receiver is cemented. From its centre
Yig, defcends the jet pipe Crt, doping outwards, to give room
for the difcharging pipe b d oi larger diameter, whole
lower extremity d fits tightly into the top of the hollow
pillar FG.
The operation of the toy is eafily underftood. Sup-
pofe the diftance from C to H (fig. 57.) three feet, which
is about A of the height at which the atmofphere would
fupport a column of water. The water poured into AB
wrould defcend through FG (the hole A being diut) till
the air has expanded -/q-, and then it would flop. If the
pipe Ca be now opened, the preffure of the air on. the
furface of the water in the ciftern EE will caufe it to
fpout through C to the height of three feet nearly, and
the water wall continue to defcend through the pipe
FG. By tempering the cock N fo as to allow the ivater
to pafs through it as fall: as it is fupplied by the jet, the
amufement may be continued a long time. It. will ftop
•at laft, however ; becaufe, as the jet is made into rare¬
fied air, a little air wall be extricated from the water,
•which will gradually accumulate in the receiver, and
diminifh its rarefa&ion, which is the moving caufe of the
jet. This indeed is an inconvenience felt in every em¬
ployment of lyphons, fo much the moire remarkably as
their top is higher than the furface of the water in the
jgp ciftern of fupply.
Syphons are Cafes of this employment of a fyphon are not unfre-
oftenufed quent. When water .collefted at A (fig. 59.) is to be
conduced in a pipe to C, fituated in a lower part of the
country, it fometimes happens, as betw-een Lochend and
Leith, that the intervening ground is higher than the
fountain-head as at B. A forcing pump is erefled at A,
and the water forced along the pipe. Once it runs out
at C, the pump may be removed, and the water will
continue to run on the fyphon principle, provided BE
do not exceed 33 feet. But the water in that part of
the conduit vftiich is above the horizontal plane AE., is
in the fame ftate as in a receiver of rarefied air, and.giv.es
out fome of the air which is chemically united with it.
This gradually accumulates in the elevated part of the
conduit, and at laft choaks it entirely. When this hap¬
pens, the forcing pump muft again be worked. Although
the elevation in the Leith conduit is only about eight or
ten feet, it will feldom run for 1 2 hours. N. B. This air
cannot be difcharged by the ufual air-cocks ; for if there
were an opening at B, the air would rufti in, and imme¬
diately flop-the motion.
This combination of air with water is very diftinft-
thus.
Kg- 55-
iSx
xSi
The air-
pump dif-
covers the
combina¬
tion of air
withwater ty feen by tneans of tlie aIr-PumP- If a lma11 glafs con*
taining cold water, frefti drawn from the faring, be ex- Elaftkity,
pofed, as in fig. 60. under the receiver, and the air rare- &LC-
fied, fmall bubbles will be obferved to form on the inner
furface of the glafs, or on the furface of any body im-
merled in it, which will increafe in fize, and then detach
themfelves from the glafs and reach the top ; as the ra-
refaftion advances, the whole water begins to Ihow very
minute air-bubbles rifing to the top; and this appearance
will continue for a very long time, till it be completely
difengaged. Warming the water will occafion a itill
farther ieparation of air, and a boiling heat will feparale
all that can be difengaged. The reafon afligncd for
thefe air-bubbles firft appearing on the furface of the
glafs, &c. is, that air is attracted by bodies, and adheres
to their furface. This may be fo. But it is more pro¬
bably owing to the attraction of the water for the giafs,
which caufes it to quit the air which it held in folution,
in the fame manner as we fee it happen when it is mix¬
ed with ipirits-of-wine, with vitriolic acid, &c. or when
falts or fugar are diffolved in it. For if we pour out
the water which has been purged of air by boiling in
vacuo, and fill the glafs with frefti water, we lhall. ob-
ferve the fame tiring, although a film of the purified
water was left adhering to the glafs. In this cafe there
can be no air adhering to the glafs.
Water thus purged of air by boiling (or even with¬
out boiling) in vacuo, will again abforb air when expo-
fed to the atmofphere. The beft demonftration of this
is to fill with this water a phial, leaving about the fize
of a pea not filled. Immerie this in a veffel of w-ater,
with the mouth undermoft, by which means the air-
bubble will mount up to the bottom of the phial. Al¬
ter fome days Handing in this condition, the air-bubble
will be completely abforbed, and the veffel quite filled
with water.
The air in this ftate of chemical folution has loft its
elafticity, for the water is not more compreflible than
common water. It is alfo found that water brought up
from a great depth under ground contains much more
air than water at the furface. Indeed fountain waters
differ exceedingly in this refpeft. The water which, now
comes into the city of Edinburgh by pipes contains io
much as to throw' it into a confiderable ebullition in va¬
cuo. Other liquors contain much greater quantities of
elaftic fluids in this loofely combined ftate. A glais of
beer treated in the fame way wTill be almoft wholly con¬
verted into froth by the efcape of its fixed air, and will
have loft entirely the prickling, fmartnefs which is fo
agreeable, and become quite vapid.
The air-pump gives us, in the next place, a great va- and illu-
riety of experiments illuftrative of the air’s elaft.icity and “?_e
expanfibility. The very operation of exhauftion, as ff tjcjt^ an^
is called, is an inftance of its great, and hitherto un- expanfibi-
limited, expanfibility. But this is. not palpably, exhibited lity.
to viewr. The following experiments Ihow7 it moft di-
ftinflly. - 7 1 • i84
I ft,' Put a flaccid bladder, of whicn tne neck is Experi-
firmly tied with a thread, under a receiver, and work merits
the pump. The bladder will gradually fwell, and will
even be fully diftended. Upon readmitting the air^J.
into the receiver, the bladder gradually collapfes again
into its former dimenfions : while the bladder is haccid,
the air within it is of the fame denfity and elafticity
with the furrounding air, and its elaliicity ba.ances
the preffure of the atmofphere. When part of the air
• u of
tS^
FNT E HJ M A TEC S: 697
IsKperi- of tile receiver is abftracked, tbe remainder expands fo
tnenu on ^ ftin tQ fl]l the receiver : but by expanding, its elafti-
■ ^r' city is plainly diminilhed } for we fee by the fa£l, that
the elafticity of the air of the receiver no longer balan¬
ces the elafticity of that in the bladder, as it no longer
keeps it in its dimenftons. The air in the bladder ex¬
pands alfo: it expands till its diminifhed elafticity is again
in equilibrio with the diminifhed elafticity of the air in
the receiver j that is, till its denfity is the fame. When
all the wrinkles of the bladder have difappeared, its air
can expand no more, although we continue to diminifh
the elafticity of the air of the receiver by further rare¬
faction. The bladder now tends to burft j and if it be
pierced by a point or knife fattened to the flip-wire, the
air wrill rufh out, and the mercury defcend rapidly in the
185 If a phial or tube be partly filled with water, and im-
merfed in a veffel of water with the mouth downwards,
the air will occupy the upper part of the phial. If this
apparatus be put under a receiver, and the air be ab-
ftrafted, the air in the phial will gradually expand, al¬
lowing the water to run out by its weight till the fur-
face of the water be on a level within and without.
When this is the cafe, we muft grant that the denfity
and elafticity of the air in the phial is the fame with that
in the receiver. When we work the pump again, we
fhall obferve the air in the phial expand ftill more, and
come out of the wuter in bubbles. Continuing the ope¬
ration, we fhall fee the air continually efcaping from the
phial : when this is over, it fhows that the pump can ra¬
refy no more. If we now admit the air into the receiver,
we fhall fee the water rife into the phial, and at laft al-
moft completely fill it, leaving only a very fmall bubble
of air at top. This bubble had expanded fo as to fill the
Fig 6r. whole phial. See this reprefented in fig. 61.
1S6 Every one muft have obferved a cavity at the big end
of ah egg between the fhell and the white. The white
and yolk are contained in a thin membrane or bladder
which adheres loofely to the fhell, but is detached from
it at that part; and this cavity increafes by keeping the
egg in a dry place. One may form a judgement of its
fize, and therefore of the freftmefs of the egg, by touch¬
ing it with the tongue ; for the fhell, where it is not in
contaft with the contents, will prefently feel warm, be¬
ing quickly heated by the tongue, while the reft of the
egg will feel cold.
If a hole be made in the oppofite end of the egg, and
it be fet on a- little tripod, and put under a receiver, the
expanfion of the air in the cavity of the egg will force
the contents through the hole till the egg be quite emp¬
tied : or, if nearly one half of the egg be taken away at
the other end, and the white and yolk taken out, and
the ihell be put under a receiver, and the air abftrafted,
the air in the cavity of the egg will expand, gradually
detaching the membrane from the fhell, till it caufes it
to fwell out, and gives the whole the appearance of an
entire egg. In like manner fhrivelled apples and other
fruits will fwell in vacuo by the expanfion of the air
Confined in their cavities.
If a piece of wood, a twig with green leaves, charcoal,
plafter of Paris, &c. be kept under water in vacuo, a
prodigious quantity of air will be extrafted ; and if we
readmit the air into the receiver, it will force the water
into the pores of the body. In this cafe the body will
riot fwirn in water as it did before, fhowing that the
Vol. XVI. Part II.
vegetable fibres are fpecifically heavier than water. It C«mprefli-
is found, however, that the air contained in the pith andbility’&c\
bark, fuch as cork, is not all extricated in this way 5 and m *
that much of it is contained in veficles which have no
outlet: being fecreted into them in the procefs of vegeta¬
tion, as it is fecreted. into the air-bladder of fifties, where
it is generally found in a pretty compreffed ftate, confl-
derably denfer than the furrounding air. The air-bladder
of a fifh is furrounded by circular and longitudinal muf-
cles, by which the fifh cancomprefs the air ftill further j
and, by ceafing to aft with them, allow it to fwell out
again. It is in this manner that the fifh can fuit its
fpecific gravity to its fituation in the water, fo as to
have no tendeancy either to rife or fink : but if the fifh
be put into the receiver of an air-pump, the rarefaftion
of the air obliges the fifh to aft more ftrongly with
thefe contrafting mufcles, in order to adjuft its fpecific
gravity; and if too much air has been abftrafted from
the receiver, the fifh is no longer able to keep its air-
bladder in the proper degree of compreflion. It becomes
therefore too buoyant, and comes to the top of the wa¬
ter, and is obliged to ftruggle with its tail and fins in
order to get down 5 frequently in vain. The air-bladder
fometimes burfts, and the fifh goes to the bottom, and
can no longer keep above without the continual aftion
of its tail and fins. When fifties die, they commonly
float at top, their contraftive aftion being now at an end.
All this may be illuftrated (but very imperfeftly) by a
fmall half blown bladder, to which is appended a bit of
lead, juft fo heavy as to make it fink in water: when
this is put under a receiver, and the air abftrafted, the
bubble will rife to the top j and, by nicely adjufting the
rarefaftion, it may be kept at any height. See fig. 6 2. Fig. 62.
The playthings called Cartejian devils are fimilar to 1S8
this : they are hollow glafs figures, having a fmall aper¬
ture in the lower part of the figures, as at the point of
the foot 5 their weight is adjufted fo that they fwim up¬
right in water. When put into a tall jar filled to the
top, and having a piece of leather tied over it, they will
fink in the wrater, by prefling on the leather with the
ball of the hand : this, by comprefling the v/ater, forces
fome of it to enter into the figure and makes it hea¬
vier than the water 5 for which reafon it finks, but rifes
again on removing the preffure of the hand. See figs.
63 and 64. _ Figs. 63.
If a half blown ox-bladder be put into a box, and ^nd 64.
great weights laid on it, and the whole be put under a
receiver, and the air abftrafted j the air will, by expand¬
ing, lift up the weights, though above an hundred
pounds. See fig. 65. _ Fig. <Sc.
By fuch experiments the great expanfibility of the 1*9
air is abundantly illuftrated, as its compreflibility wasCofT1Pret^','
formerly by means of the condenfing fyringe. Webl ityr(ni
now fee that the two fets of experiments form an unin- ilty are in
terrupted chain *, and that there is no particular ftate of no ftate of
the air’s denfity where the compreffibility and expanfi-the air very*
bility are remarkably diflimilar. Air in its ordinary ftate
expands; becaufe its ordinary ftate is a ftate of com-
preflion by the weight of the atmofphere : and if there
were a pit about 33 miles deep, the air at the bottom
would probably be as denfe as water \ and if it were 50;
miles deep, it would be as denfe as gold, if it did not be¬
come a liquid before this depth : nay, if a bottle with
its mouth undermoft were immerfed fix miles under
water, it would probably be as denfe as water ; we fay
4 T probably,
698 P N E U M
iSxperi- probably, for this depends on the nature of its compref-
on Air Ability 3 that is, on the relation which fubfifts between
1 - v the compreffion and the force which produces it.
150 This is the circumftance of its conftitution, which we
Relation now proceed to examine 5 and it is evidently a very im-
between portant circumftance. We have long ago obferved,
fion and" t^at t^e great compreffibility and permanent fluidity of
the force a^r* obferved in a vaft variety of phenomena, is totally
producing inexplicable, on the fuppofition that the particles of air
ih. are like fo many balls of fponge or fo many foot-balls.
Give to thofe what compreffibility you pleafe, common
air could no more be fluid than a mafs of clay 3 it could
no more be fluid than a mafs of fuch balls preffed into a
box. It can be demonftrated (and indeed hardly needs
a demonftration), that before a parcel of fuch balls, juft
touching each other, can be fqueezed into half their
prefent dimenfions, their globular ffiape will be entirely
gone, and each will have become a perfedl cube, touch¬
ing fix other cubes with its whole furface 3 and thefe
cubes will be ftrongly compreffed together, fo that mo¬
tion could never be performed through among them by
any folid body without a very great force. Whereas
we know that in this ftate air is juft as permeable to
every body as the common air that we breathe. There
is no way in which we can reprefent this fluidity to our
imagination, but by conceiving air to confift of particles,
not only difcrete, but diftant from each other, and a flo¬
ated by repulfive forces, or fomething analogous to them.
It is an idle fubterfuge, to wdiich fome naturalifts have
recourfe, faying, that they are kept afunder by an in¬
tervening ether, or elaftic fluid of any other name.
This is only removing the difficulty a ftep farther off':
for the elafticity of this fluid requires the fame explana¬
tion 3 and therefore it is neceffary, in obedience to the
rules of juft reafoning, to begin the inquiry here 3 that
is, to determine from the phenomena what is the analo¬
gy between the diftances of the particles and the repul¬
five forces exerted at thefe diftances, proceeding in the
feme way as in the examination of planetary gravitation.
We fhall learn the analogy by attending to the analogy
between the compreffing force and the denfity.
I9I For the denfity depends on the diftance between the
j j lt:J ex' particles 3 the nearer they are to each other, the denfer
applied to t^ie a^r- Suppofe a fquare pipe one inch wide and
air.. eight inches long, ffiut at one end, and filled with com¬
mon air 3 then fuppofe a plug fo nicely fitted to this
pipe that no air can pafs by its fides 3 fuppofe this pi-
fton thruft down to within an inch of the bottom : it is
evident that the air which formerly filled the whole pipe
now occupies the fpace of one cubic inch, which con¬
tains the fame number of particles as were formerly dif-
fufed over eight cubic inches.
The condenfation would have been the fame if the air
which fills a cube whofe fide is two inches had been
fqueezed into a cube of one inch, for the cube of two
inches alfo contains eight inches. Now, in this cafe it
is evident that the diftance between the particles would
be reduced to its half in every dire£lion. In like manner,
if a cube whofe fide is three inches, and which therefore
contains 27 inches, be fqueezed into one inch, the dif¬
tance of the particles will be one-third of what it was: in
general the diftance of the particles will be as the cube-
root of the fpace into which they are compreffed. If
the fpace be -rlx> f°rmer dimenfions,
the diftance of the particles will be &c. Now
A T I C S.
the term denjity, in its ftrict fenfe, expreffes the vicini- ComprefK-
ty of the particles 3 denji arbores are trees growing near
each other. The meafure of this vicinity therefore is v
the true meafure of the denfity 3 and when 27 inches of
air are compreffed into one, we fhould fay that it is
three times as denfe 3 but we fay, that it is 27 times
denfer. 193
Denfity is therefore ufed in a fenfe different from its Farther
ftridteft acceptation : it expreffes the comparative number e.xP^ana*
of equidiftant particles contained in the fame bulk.tlori
This is alfo abundantly precife, when we compare bodies
of the fame kind, differing in denfity only 3 but we alfo
fay, that gold is 19 times denfer than water, becaufe
the fame bulk of it is 19 times heavier. This affertion
proceeds on the affumption, or the fa61, that every ulti¬
mate atom of terreftrial matter is equally heavy : a par¬
ticle of gold may contain more or fewer atoms of matter
than a particle of water. In fuch a cafe, therefore, the
term denfity has little or no reference to the vicinity of
the particles ; and is only a term of comparifon of other
qualities or accidents.
But when we fpeak of the refpe6tive denfities of the
fame fubftance in its different ftates of compreffion, the
word denjity is ftridlly connedled with vicinity of parti¬
cles, and we may fafely take either of the meafures.
We (hall abide by the common acceptation, and call
that air. eight times as denfe which has eight times as
many particles in the fame bulk, although the particles
are only twice as near to each other. 193
Thus then we fee, that by obferving the analogy be- The ana-
tween the compreffing force and the denfity, we (hall Je^et"j
difeover the analogy between the compreffing force and C^pref-C
the diftance of the particles. Now the force which is fing force
neceffary for compreffing two particles of air to a cer- and the di-
tain vicinity is a proper meafure of the elafticity of the ^ance
particles correfponding to that vicinity or diftance 3 for ^ p^1~
it balances it, and forces which balance muft be efteem-
ed equal. Elafticity is a diftindlive name for that cor-
pufcular force which keeps the particles at that diftance:
therefore obfervations made on the analogy between
the compreffing force and the denfily of air will give us
the law of its corpufcular force, in the fame way that
obfervations on the fimultaneous defledlions of the pla¬
nets towards the fun give us the law of celeftial gravi¬
tation.
But the fenfible compreffing forces which we are able T94
to apply is at once exerted on unknown thoufands of
particles, while it is the law of adlion of a Angle par¬
ticle that we want to difeover. We muft therefore
know the proportion of the numbers of particles on which
the compreffing force is exerted. It is eafy to fee, that
fince the diftance of the particles is as the cube root of
the denfity inverfely, the number of particles in phyfical
contadl writh the compreffing furface muft be as the
fquare of this root. Thus when a cube of 8 inches is
compreffed into one inch, and the particles are twice as
near each other as they were before, there muft be four
times the number of particles in contadl with each of
the fides of this cubical inch 3 or, when wre have puftied
down the fquare pifton of the pipe fpoken of above to
within an inch of the bottom, there will be four times
the number of particles immediately contiguous to the
pifton, and refilling the compreffion 3 and in order to
obtain the force really exerted on one particle, and the
elafticity of that particle, we xnuft divide the whole com-t
prefling
*95
Experi¬
ments eila-
E*peri- prefling force by 4. In like manner, if we have com¬
ments preffed air into TrT °f its former bulk, and brought the
on Air~ , particles to 4 of their former diftance, we muft divide
^ ^ the comprefling force by 9. In general if d exprefs the
denfity, 1 - will exprefs the diftance # of the par-
tides 5 3 V^, or dS, will exprefs the vicinity or real
denfity *, and </T will exprefs the number of particles
afting on the comprefling furface : and if / exprefs the
accumulated external comprefling force, “T will exprefs
d3
the force afting on one particle ; and therefore the elaf-
ticity of that particle correfponding to the diftance x.
We may now proceed to confider the experiments by
which the law of compreflion is to be eftablifhed.
. The firft experiments to this purpofe Were thofe made
the law of by Mr Boyle, publilhed in 1661 in his Defenjjo Doc-
cornpref- trines dc Arris Elatei'e contra Linum, and exhibited be-
lion. fore the Royal Society the year before. Mariotte made
experiments of the fame kind, which were publiflied in
1676 in his EJfaifur la Nature de l'Air and Trade des
Mouvetnens des Eaux. i he moft copious experiments
are thofe by Sulzer {Mem. Berlin, ix.), thofe by hon-
tana {Opufc. Physico-Math.), and thofe by Sir George
Shuckburgh and Gen. Roy.
T96 In order to examine the compreflibility of air that is
ComprefTi- not rarer than the atmofphere at the furface of the earth,
bility of airwe empi0y a bent tube or fyphon ABCD (fig. 66.), her-
thanthe1 nietically fealed at A and open at D. The ftiort leg
atmofphere AB muft be very accurately divided in the proportion of
at the its folid contents, and fitted with a fcale whote units de¬
earth’s fur- note equai increments, not of length, but of capacity.
There are various ways of doing this •, but it requires
the moft fcrupulous attention, and without this the ex¬
periments are of no value. In particular, tne arched
form at A muft be noticed. A fmall quantity of mer¬
cury muft then be poured into the tube, and palled
backwards and forv/ards till it Hands (the tube being
held in a vertical pofition) on a level at B and C. Then
we are certain that the included air is of the fame den¬
fity with that of the contiguous atmofphere. Mercury
is now poured into the leg DC, which will fill it, fup-
pofe to G, and will comprefs the air into a fmaller fpace
AE. Draw the horizontal line EF : the new bulk of
the comprefled air is evidently AE, meafured by the
adjacent fcale, and the addition made to the compref-
fing force of the atmofphere is the weight of the. column
GF. Produce GF downwards to H, till FH is equal
to the height Ihown by a Toricellian tube filled with the
fame mercury; then the whole comprefling force is
"HG. This is evidently the meafure of the elafticity of
the comprefled air m AE, for it balances it. Now
pour in more mercury, and let it rife to g, comprefling
the air into Ke. Draw the horizontal line ef and
make fh equal to FH j then A<? will be the new bulk
AB
of the comprefled air, will be its new denfity, and
hg will be the meafure of the new elafticity. This ope¬
ration may be extended as far as we pleafe, by length-
face.
Fig. 65.
ening the tube CD, and taking card that it be ftreng
enough to refill the great preilure. Great care muft be • ,, — j
taken to keep the whole in a conftant temperature, be-
caufe the elafticity of air is greatly affected by heat, and
the change by any increafe ot temperature is different
according to its denfity or compreflion. T?7
The experiments of Boyle, Mariotte, Amontons, and^Pe"')f
others, were not extended to very great ^ compreflions, Boyiej
the denfity of the air not having been quadrupled in any neither
of them 5 nor do they feem to have been made with very nicely made
great nicety. It may be collected from them in gene-^extend*
ral, that the elafticity of the air is very nearly proper- great com-
tioned to its denfity ; and accordingly this law was al- preflions.
moft immediately acquiefced in, and was called the
Boylean law : it is accordingly afiumed by almoft all
writers on the fubjedt as exact. Of late years, how¬
ever, there occurred queftions in which it was of im¬
portance that this point ftiould be more fcrupuloufly fet¬
tled, and the former experiments were repeated and ex¬
tended. Sulzer and Fontana have carried them farther
than any other. Sulzer comprefled air into one-eighth
of its former dimenfions. .
Confiderable varieties and irregularities are to be ob-Varieties,
ferved in thefe experiments. It is extremely difficult to ^f^nex_
preferve the temperature of the apparatus, particularly ^imenjSi(
of the leg AB, which is moft handled. A great quan¬
tity of mercury muft be employed •, and it does not ap¬
pear that philofophers have been careful to have it pre-
cifely fimilar to that in the barometer, which gives ns
the unit of compreffing force and of elafticity.. The
mercury in the barometer ffiould be pure aud boiled.
If the mercury in the fyphon is adulterated with bifmuth
and tin, which it commonly is to a confiderable degree,
the comprefiing force, and confequently the elafticity,
will appear greater than the truth. If the barometer
has not been nicely fitted, it wall be lower than it fliould
be, and the compreffing force will appear too. great, be-
caufe the unit is too fmall 5 and this errqr will be moft
remarkable in the fmaller compreffions. . i99
The greateft fource of error and irregularity in the Heteroge-
experiments is the very heterogeneous nature of the air^^J1^
itfelf. Airis a folvent of all fluids, all vapours, and
perhaps of many folid bodies. It is highly improbable greateft
that the different compounds {hall have the fame elafti- fource of
city, or even the fame law' of elafticity : and it is wellerror*
known, that air, loaded with w'ater or other volatile
bodies, is much more expanfible by heat than pure air j
nay, it would appear from many experiments, that cer¬
tain determinate changes both of denfity and of tempe¬
rature, caufe air to let go the vapours wffiich it holds in
folution. Cold caufes it to precipitate w'ater, as ap¬
pears in dew; fo does rarefaftion, as is feen in the re¬
ceiver of an air-pump. 200
In general, it appears that the elafticity of air does The air’s
not increafe quite fo fall as its denfity. This will be
beft feen by the following tables, calculated from the increa(-e
experiments of Mr Sulzer. The column E in each faft as its
fet of experiments exprefles the length of the column denfity.
GH, the unit being FH, while the column D exprefles
AB
AE*
4 T 2
1 ft
7oo
PNEUMATICS.
Experi¬
ments on
Air.
to i
i ft Set.
D
1.000
I.IOO
1.222
i-375
i.571
1.692
1-833
2.000
2.288
2.444
3-T43
3.666
4.000
4.444
4.888
5-5^0
5.882
1.000
1.093
1.211
1.284
1- 559
1.669
1.796
1.958
2.130
2- 375
2.936
3- 391
3.706
4- °35
4'438
4.922
5- 522
2d Set.
D
1.000
1.236
1.294
I-375
1.466
1-571
1.692
2.000
2.444
3- I43
3.666
4- 444
5- 5oo
7-333
E
1.000
1.224
1.288
I-332
I-4I7
I-5I5
1.64.7
1.964
2.392
3.078
3-575
4.320
5.096
6.694
3d Set.
I)
1.000
1.091
1.200
1-333
i.;oo
1.714
2.000
2,400
3.000
4.000
6.000
8.0C0
E
1.000
1.076
1.183
1- 3°3
1.472
1.659
1.900
2.241
2- 793
3- 631
5- 297
6- 835
302
There appears in thefe experiments fufticient grounds
for calling in queftion the Roylean law } and the writer
of this article thought it incumbent on him to repeat
them with fome precautions, which probably had not
been attended to by Mr Sulzer. He was particularly
anxious to have the air as free as poflible from rnoifture.
For this purpofe, having detached the flrort leg of the
fyphon, which was 34 inches long, he boiled mercury
in it, and filled it with mercury boiling hot. He took
a tinplate veffel of fufficient capacity, and put into it a
quantity of powdered quicklime juft taken from the
kiln 5 and having clofed the mouth, he agitated the
lime through the air in the veffel, and allowed it to re¬
main there all night. He then emptied the mercury out
of the fyphon into this veffel, keeping the open end
far within it. By this means the fhort leg of the fy¬
phon was filled with Very dry air. The other part
was now joined, and boiled mercury put into the bend
of the fyphon ; and the experiment was then profecuted
with mercury which had been recently boiled, and was
the fame with which the barometer had been carefully
filled.
The refults of the experiments are expreffed in the
following table.
Dry Air.
D
1.000
2.000
3.000
4.000
5-500
6.000
7.620
E
1.000
I-957
2.848
3- 737
4- 93°
5- 342
6.490
Moift Air.
D
1.000
2.000
3.OOO
4.000
5-5°0
6.000
7.620
E
1.000
1.920
2.839
3.726
5.000
5- 452
6- 775
Damp Air.
D
1.000
2.000
3.000
4.000
5-5°0
6.000
7.620
1.000
1.909
2.845
3-7l8
5-io4
5463
6.812
203
204
2®5
206
Here it appears again in the cleareft manner that the
elafticities do not increafe as faft as the denfities, and
the differences are even greater than in Mr Sulzer’s ex- Eiaflicity.
periments. -y—---
The fecond table contains the refults of experiments
made on very damp air in a warm fummer’s morning.
In thefe it appears that the elafticities are almoft pre-
cifely proportional to the denfities 4- a ftnall conftant
quantity, nearly 0.11, deviating from this rule chiefly
between the denfities 1 and 1.5, within which limits we
have very nearly D—E1-0017. As this air is nearer to
the conftilution of atmofpheric air than the former, this
rule may be fafely followed in cafes where atmofpheric
air is concerned, as in meafuring the depths of pits by
the barometer.
The third table (hows the compreftion and elafticity
of air ftrongly impregnated with the vapours of cam-
phire. Here the Boylean law appears pretty exadl, or
rather the elafticity feems to increaie a little fafter than
the denfity.
Dr Hooke examined the compreffion of air by im-
merfing a bottle to great depths in the fea, and weigh¬
ing the water which got into it without any efcape of
air. But this method was liable to great uncertainty,
on account of the unknown temperature of the fea at
great depths.
Hitherto we have confidered only fuch air as is not Mode of
rarer than what we breathe ; we muft take a very dif- examining
ferent method for examining the elallicity of rarefied t!?e
0 J city of ra-
alr" _ refied air*
Let gh (fig. 67.) be a long tube, formed a-top into Fig. 67.
a cup, and of fufficient diameter to receive another
fmaller tube af, open at firft at both ends. Let the
outer tube and cup be filled with mercury, which will
rife in the inner tube to the fame level. Let a f now
be flopped at a. It contains air of the fame denfity and
elafticity with the adjoining atmofphere. Note exactly
the fpace a b which it occupies. Draw it up into the
pofition of fig. 68. and let the mercury ftand in it at the Fig. 68.
height de, while ce is the height of the mercury in the
barometer. It is evident that the column de is in equi-
librio between the preffure of the atmofphere and tire
elafticity of the air included in the fpace ad. And
fince the weight of c e would be in equilibrio with the
whole preffure of the atmofphere, the weight of ccMs
equivalent to the elafticity of the included air. W hile
therefore ce is the meafure of the elafticity of the fur¬
rounding atmofphere, c d will be the meafure of the
elafticity of the included air ; and fince the air original¬
ly occupied the fpace a b, and has now expanded into
a d, we have —.for the meafurc of its denfity. N. B.
ad
c e and c d are meafured by the perpendicular heights of
the columns, but ab and ad muft be meafured by their
folid capacities.
By raifing the inner tube ftill higher, the mercury
will alfo rife higher, and the included air will expand
ftill farther, and we obtain another c d, and another
—and in this manner the relation between the denfity
ad
and elafticity of rarefied air may be difcovered. 208
This examination may be managed more eafily ky^ethodby
means of the air-pump. Suppofe a tube a e (fig. 69.) means of
containing a fmall quantity of air a b, fet up in a ciftern the air-
of mercury, which is fupported in the tube at the height Ifmh-
207
P N E U M A T I C S.
Experi- e b, and let e c'be the height of the mercury in the ba-
mtnts on rom?.(er> Let this apparatus be fet under a tubulated
. receiver on the pump-plate, and let ^ « be the pump-
gage, and m n be made equal to c e.
Then, as has been already (hown, c b is the meamre
of the elatlicity of the air in a b, correfponding to the
bulk a b. Now let fome air be abftradted from the re¬
ceiver. The elafticity of the remainder will be dimi-
nifhed by its expanfion ; and therefore the mercury in
the tube a e will defcend to fame point d. For the fame
reafon, the mercury in the gage will rife to fome point
o, and m o will exprefs the elafticity of the air in the
receiver. This would fupport the mercury in the tube
a e at the height e r, if the fpace a r were entirely void
of air. Therefore r is the effedt and meafure of the
elafticity of the included air when it has expanded to
the bulk « d; and thus its elafticity, under a variety of
other bulks, may be compared with its elafticity when
of the bulk a b. When the air has been fo far abftratft-
ed from the receiver that the mercury \n a e defcends to
e, then m o will be the precife meafure of its elaftioity.
In all thefe cafes it is neceffary to compare its bulk
a b with its natural bulk, in which its elafticity balances
the preffure of the atmofphere. This may be done by
laying the tube a e horizontally, and then the air will
209 collapfe into its ordinary bulk.
Another Another ealy method may be taken for this exami-
eafy me- nation. Let an apparatus a be de./(fig. 70.) be made,
thod. confifting of a horizontal tube a e of even bore, a ball
* '£• 7°- dg e of a large diameter, and a fwan-neck tube hf Let
the ball and part of the tube £ be filled with mer¬
cury, fo that the tube may be in the fame horizontal
plane with the furface d e of the mercury in the ball.
Then feal up the end and conneft /with an air-pump.
When the air is abftrafled from the furface d e, the air
in a b wall expand into a larger bulk a c, and the mer¬
cury in the pump-gage will rife to fome diftance below
the barometric height. It is evident that this diftance,
without any farther calculation, will be the meafure of
the elaftiexty of the air prefling on the furface d e, and
a 10 therefore of the air in a e.
The moft The moft exaft of all methods is to fufpend in the
of examilfC rece’lVer ^ aT1 air-pump a glafs veiTel, having a very
ing this " narrow mouth, over a ciftern of mercury, and then ab-
elaltidty. ftraft the air till the gage rifes to fome determined
height. The difference e between this height and the
barometric height determines the elafticity of the air in
the receiver and in the fufpended veffel. Now lower
down that veffel by the flip-wire till its mouth is im-
merfed into the mercury, and admit the air into the re¬
ceiver 5 it will prefs the mercury into the little veffel.
Lower it ftill farther down, till the mercury v/ithin it
is level with that without $ then flop its mouth, take
it out and weigh the mercury, and let its weight be w.
Subtraft this weight from the weight v of the mer¬
cury, which would completely fill the whole veffel j
then the natural bulk of the air will be v—w, while
its bulk, when of the elafticity e in the rarefied receiver,
was the bulk 'or capacity w of the veffel. Its denfity
therefore, correfponding to this elafticity e, was —~W.
And thus may the relation between the denfity and ela¬
fticity in all cafes be obtained.
A great variety of experiments to this purpofe have
been made, with different degrees of attention, accord-
701
ing to the intereft which the philofophers had in the Boylean
remit. Thofe made by M. de Luc, General Roy, Mr Law. ,
Trembley, and Sir George Shuckburgh, are by far 2t£
the moft accurate} but they are all confined to very mo-Various ex¬
derate rarefactions. The general refult has been, that periments
the elafticity of rarefied air is very nearly proportional hav^^eJ:u
to its denfity. We cannot fay with confidence that any
regular deviation from this law has been obferved, there p0fe>
being as many obfervations on one fide as oh the other;
but we think that it is not unworthy the attention of
philofophers to determine it with precifion in the cafes
of extreme rarefaftion, where the irregularities are moft
remarkable. The great fource of error is a -certain ad-
hefive fluggifhnefs of the mercury when the impelling
forces are very fmall *, and other fluids can hardly be
ufed, becaufe they either fmear the infide of the tube and
diminhh its capacity, or they are converted into vapour,
which alters tke law of elafticity. 2I2
Let us, upon the whole, affume the Boylean law, era. The Boyle-
that the elafticity of the air is proportional to its denfity. an may
The law deviates not in any fenfible degree from
truth in thofe cafes which are of the greateft praftical
importance, that is, when the denfity does not much
exceed or fall (hort of that of ordinary air. ^
Let us now fee what information this gives us with Inveftiga-
refpeft to the aftion of the particles on each other. tion of the
The inveftigation is extremely eafy. We have feen ^lonr°^
that a force eight times greater than the preffure °fclesoneach
the atmofphere will comprefs common air into the other,
eighth part of its common bulk, and give it eight times
its common denfity : and in this cafe we know, that
the particles are at half their former diftance, and that
the number which are now a ft ing on the furface of the
pifton employed to comprefs them is quadruple of the
number which aft on it when it is of the common den¬
fity. Therefore, when this eightfold comprefling force
is diftributed over a fourfold number of particles, the
portion of it which afts on each is double. In like
manner, when a comprefling force 27 is employed,
the air is compreffed into ttt of its former bulk, the
particles are at y of their former diftance, and the force
is diftributed among 9 times the number of particles ,
the force on each is therefore 3. In ftiort, let - be the
diftance of the particles, the number of them in any
given veffel, and therefore the denfity will be as a?'5,
and the number prefling by their elafticity on its whole
internal furface will be as x'1. Experiment Ihows, that
the compreffing force is as a:5, which being diftributed
over the number as at1, will give the force on each as *v
Now this force is in immediate equilibrium with the
elafticity of the particle immediately contiguous to the
comprefling furface. This elafticity is therefore as x :
and it follows from the nature of perfeft fluidity, that
the particle adjoining to the comprefling furface preffes
with an equal force on its adjoining particles on every
fide. Hence we muft conclude, that the corpufcular
repulfions exerted by the adjoining particles are inverfely
as their diftances from each other, or that the adjoining 2I^
particles tend to recede from each other with forces in- Sir Ifaac
verfely proportional to their diftances. Newton
Sir Ifaac Nervton was the firft who reafoned in this
manner from the phenomena. Indeed he was the firft rf a[-onPC}
who had the patience to refleft on the phenomena with properly
any precifion. His difeoveries in gravitation naturally on this fub-
gave
PNEUMATICS.
-ZJ02
Eoylean gave his thoughts this turn, and he very early hinted
, J aw- his fufpicions that all the charadteriftic phenomena of
* tangible matter were produced by forces which were ex¬
erted by the particles at fmall and infenfible diftances:
And he confiders the phenomena of air as affording an
' excellent example of this inveftigation, and deduces from
them the law wdiich we have now demonllrated j and
fays, that air confifts of particles which avoid the ad¬
joining particles with forces inverfely proportional to
their diftances from each other. From this he deduces
(in the td book of his Principles) feveral beautiful pro-
pofitions, determining the mechanical conftitution of the
atmofphere.
"Limits the ®Ut ^ mU^ ke noticed that he limits this adfion to the
adlion to adjoining particles : and this is a remark of immenfe
adjoining confecjuence, though not attended to by the numerous
particles, experimenters who adopt the law.
It is plain that the particles are fuppofed to aft at a
diftance, and that this diftance is variable, and that the
forces diminilh as the diftances increafe. A very ordi¬
nary air-pump will rarefy the air 125 times. The di¬
ftance of the particles is now 5 times greater than be¬
fore 5 and yet they ftill repel each other : for air of this
denfity will ftill fupport the mercury in a fyphon-gage
at the height of 0.24, or of an inch : and a better
pump will allow this air to expand twice as much, and
ftill leave it elaftic. Thus we fee that whatever is .the
diftance of the particles of common air, they can aft
five times farther off. The queftion comes now to be,
Whether, in the ftate of common air, they really do aft
five times farther than the diftance of the adjoining par¬
ticles ? While the particle a afts on the particle b with
the force 5, does it alfo aft on the particle c with the
force 2.5, on the particle d with the force 1.667, on the
particle e with the force 1.25, on the particle f with
the force I, on the particle ^ with the force 0.8333, &.c. ?
2I5 Sir Ifaac Newton fhow's in the plaineft manner, that
this is by no means the cafe j for if this were the cafe,
he makes it appear that the fenfible phenomena of con-
denfation would be totally different from what we ob-
ferve. The force neceffary for a quadruple condenfa-
tion would be eight times greater, and for a nonuple
condenfation the force muft be 27 times greater. Two
fpheres filled with condenfed air muft repel each other,
and two fpheres containing air that is rarer than the
furrounding air muft attraft each other, &c. &c. All
this will appear very clearly, by applying to air the rea-
foning which Sir Ifaac Newton has employed in dedu¬
cing the fenfible law of mutual tendency of two fpheres,
which confift of particles attrafting each other with
forces proportional to the fquare of the diftance in¬
verfely.
If we could fuppofe that the particles of air repelled
each other with invariable forces at all diftances within
fome fmall and infenfible limit, this would produce a
compreflibility and elafticity fimilar to what we obferve.
For if we confider a row of particles, within this limit,
as compreffed by an external force applied to the two ex¬
tremities, the aftion of the whole row on the extreme
points would be proportional to the number of particles,
that is, to their diftance inverfely and to their denfity : and
a number of fuch parcels, ranged in a ftraight line, would
conftitute a row of any fenfible magnitude having the
fame law of compreflion. But this law of corpufcular Height of
force is unlike every thing we obferve in nature, and to ^ Atmo«
the laft degree improbable. , 13 ^re‘ f
We muft therefore continue the limitation of this mu- 2iS
tual repulfion of the particles of air, and be contented
for the prefent with having eftabliftied it as an experi¬
mental faft, that* the adjoining particles of air are kept
afunder by forces inverfely proportional to their diftan¬
ces : or perhaps it is better to abide by the fenfible law,
that the denjity of air is proportional to the comprefjjng
force. This law is abundantly fufficient for explaining
all the fubordinate phenomena, and for giving us a com¬
plete knowledge of the mechanical conftitution of our
atmofphere. 219
And in the firft place, this view of the compreffi-TIie height
bility of the air muft give us a very different notion of. th(f.air
the height of the atmcfphere from what we deduced onte£i fro^j*
a former occafion from our experiments. It is found, confidering
that when the air is of the temperature 3 2° of Fah- its compref-
renheit’s thermometer, and the mercury in the barome-^^H* &c*
ter Hands at 30 inches, it will defcend one-tenth of an
inch if we take it to a place 87 feet higher. Therefore,
if the air were equally denfe and heavy throughout, the
height of the atmofphere would be 30 X 10 X 87 feet, or
5 miles and 100 yards. But the loofe reafoning addu¬
ced on that occafion was enough to fhow us that it muft
be much higher j becaufe every ftratum as we afcend
muft be fucceflively rarer as it is lefs compreffed by in¬
cumbent weight. Not knowing to what degree air ex¬
panded when the compreflxon was diminiftied, we could
not tell the fucceflive diminutions of denfity and confe-
quent augmentation of bulk aWl height j we could only
fay, that feveral atmofpheric appearances indicated a
much greater height. Clouds have been feen much
higher 5 but the phenomenon of the twilight is the moft
convincing proof of this. There is no doubt that the vi-
fibility of the Iky or air is owing to its want of perfeft
tranfparency, each particle (whether of matter purely
aerial or heterogeneous) reflefting a little light.
Let b (fig. 71.) be the laft particle of illuminated airpig. ^
which can be feen in the horizon by a fpeftator at A.
This muft be illuminated by a ray SD b, touching the
earth’s furface at fome point D. Now it is a known
faft, that the degree of illumination called twilight is
perceived when the fun is 18° below the horizon of the
fpeftator, that is, when the angle E S or ACD is 18
degrees j therefore £ C is the fecant of 9 degrees (it is
lefs, viz. about 84 degrees, on account of refraftion).
We know the earth’s radius to be about 3970 miles:
hence we conclude £ B to be about 45 miles j nay, a
very fenfible illumination is perceptible much farther
from the fun’s place than this, perhaps twice as far, and
the air is fufficiently denfe for reflefting a fenfible light
at the height of nearly 200 miles. 2JI
We have now feen that air is prodigioufly expanfible. Experiment
None of our experiments have diftinftly fhown us any fees no li-
limit. But it does not follow that it is expanfible with- ^ t0 the
out end \ nor is this at all likely. It is much more ^iiitey>pan'
probable that there is a certain diftance of the parts in
which they no longer repel each other $ and this would
be the diftance at which they would arrange themfelves
if they were not heavy. But at the very fummit of the
atmofphere they will be a very fmall matter nearer to
each other, on account of their gravitation to the earth.
TiH
3
Height Oi
the Atmo-
fphere.
- 222
Farther ob-
fervations
on, and in-
vefligation
of, the
height of
the atmo-
fphere.
223
224
225
Fi'g. 72.
P N E U M
Till we know preeifely the law of this mutual repul-
fion, we cannot fay what is the height of the atmo-
fphere.
But if the air be an elaftic fluid whofe denflty is al¬
ways proportionable to the comprefling force, w7e can
tell w'hat is its denfity at any height above the furface
of the earth : and w7e can compare the denfity fo calcu¬
lated with the denfity difcovered by obfervation : for
this lafl is meafured by the height at which it fupports
mercury in the barometer. This is the dire£t meafure
of the preffure of the external air •, and as we know the
law of gravitation, we can tell wThat w7ould be the pref¬
fure of air having the calculated denfity in all its
parts.
Let us therefore fuppofe a prifmatic or cylindric co¬
lumn of air reaching to the top of the atmofphere.
Let this be divided into an indefinite number of ftrata
of very fmall and equal depths or thicknefs} and let us,
for greater fimplicity, fuppofe at firft that a particle of
air is of the fame weight at all dillances from the cen¬
tre of the earth.
The abfolute weight of any one of thefe flrata wall
on thefe conditions be proportional to the number of
particles or the gravity of air contained in it •, and fince
the depth of each ftratum is the fame, this quantity of
air will evidently be as the denfity of the ftratum : but
the denlity of any ftratum is as the comprefling force ;
that is, as the preffure of the ftrata above it 5 that is, as
their weight} that is, as their quantity of matter—there¬
fore the quantity of air in each ftratum is proportional
to the quantity of air above it 5 but the quantity in
each ftratum is the difference between the column incum¬
bent on its bottom and on its top : thefe differences are
therefore proportional to the quantities of wdiich they
are the differences. But when there is a feries of quan¬
tities which are proportional to their owm differences,
both the quantities and their differences are in continual
or geometrical progreffion : for let a, Zq f, be three fuch
quantities that
b : c=a—b : b—c, then by alter.
b : a—b— c : b—c and by compof.
b: a—c : b
and a : b—b : c
therefore the denfities of thefe ftrata decreafe in a geo¬
metrical progreffion j that is, wdien the elevations above
the centre or furface of the earth increafe, or their depths
under the top of the atmofphere decreafe, in an arithme¬
tical progreflion, the denfities decreafe in a geometrical
progreflion.
Let AR£) (fig. 72.) reprefent the feftion of the earth
by a plane through its centre O, and let wiOAM be a
vertical line, and AE perpendicular to OA will be a
horizontal line through A, a point on the earth’s furface.
Let AE be taken to reprefent the denfity of the air at
A *, and let DH, parallel to AE, be taken to AE as
the denfity at D is to the denfity at A : it is evident,
that if a logiftic or logarithmic curve EHN be drawn,
having AN for its axis, and pafling through the points
E and PI, the denfity of the air at any other point C,
in this vertical line, will be reprefented by CG, the or¬
dinate to the curve in that point : for it is the property
of this curve, that if portions AB, AC, AD, of its ax¬
is be taken in arithmetical progreffion, the ordinates,
AE, BE, CG, DH, will be in geometrical progref-
fiom
-v—
226
227
22!
A T I C S. 703
It is another fundamental property of this curve, that Height of
if EK or HS touch the curve in E or H, the fubtangent thfe}^°‘
AK or DS is a conftant quantity. v
And a third fundamental property is, that the infinite¬
ly extended area MAEN is equal to the reftangle KA
EL of the ordinate and fubtangent \ and, in like man¬
ner, the area MDHN is equal to SD X DH, or to KA
X DH ; confequently the area lying beyond any ordinate
is proportional to that ordinate.
Thefe geometrical properties of this curve are all ana¬
logous to the chief circumftances in the conftitution of
the atmofphere, on the fuppofition of equal gravity.
The area MCGN reprefents the w7hole quantity of aereap
matter wThich is above C : for CG is the denfity at C,
and CD is the thicknefs of the ftratum between C and
D ; and therefore CGHD will be as the quantity of mat¬
ter or air in it; and in like manner of all the others, and
of their fums, or the w'hole area MCGN : and as each
ordinate is proportional to the area above it, fo each den¬
fity, and the quantity of air in each ftratum, is propor¬
tional to the quantity of air above it: and as the whole
area MAEN is equal to the reftangle KAEL, fo the
whole air of variable denfity above A might be contain¬
ed in a column KA, if, inftead of being compreffed by
its ow7n weight, it were without weight, and compreffed
by an external force equal to the preffure of the air at
the furface of the earth. In this cafe, it w7ould be of the
uniform denfity AE, which it has at the furface of the
earth, making what we have repeatedly called the homo¬
geneous atmofphere.
Hence we derive this important circumftance, that-the 22^
height of the homogeneous atmofphere is the fubtangent
of that curve whofe ordinates are as the denfities of the
air at different heights, on the fuppofition of equal gravi¬
ty. This curve may with propriety be called the at¬
mospherical LOGARITHMIC : and as the different loga-
rithmics are all charafterifed by their fubtangents, it is of
importance to determine this one.
It may be done by comparing the denfities of mercury'
and air. For a column of air of uniform denfity, reach¬
ing to the top of the homogeneous atmolphere, is in
equilibrio with the mercury in the barometer. Now it
is found, by the beft experiments, that when mercury
and air are of the temperature 3 2° of Fahrenheit’s ther¬
mometer, and the barometer ftands at 30 inches, the
mercury is nearly 10440 times denfer than air. There-,
fore the height of the homogeneous atmofphere is 10440
times 30 inches, or 26100 feet, or 8700 yards, or 4350
fathoms, or 5 miles wanting 100 yards.
Or it may be found by obfervations on the barometer.. 230
It is found, that when the mercury and air are of the
above temperature, and the barometer on the fea-flrore
ftands at 30 inches, if we carry it to a place 884 feet
higher it will fall to 29 inches. Now, in all logarith¬
mic curves having equal ordinates, the portions of the
axes intercepted between the correfponding pairs of ordi¬
nates are proportional to the fubtangents. And the lub-
tangents of the curve belonging to our common tables is
0.434294and the difference of the logarithms of 30
and 29 (which is the portion of the axis intercepted be¬
tween the ordinates 30 and 29), or 0.0147233, is to
0.4342945 as 883 is to 26058 feet, or 8686 yards, or
4343 fath°ms> or 5 miles wanting 114 yards. This de¬
termination is 14 yards lefs than the other, and it is un¬
certain which is the more ex aft. It is extremely difficult
to i
PNEUMATICS.
Height
of the At-
raofphere.
’31
to meafurc die refpettive denfities of mercury and air-,
and in meafuring the elevation which produces a fall of
one inch in the barometer, an error of ^ of an inch
would produce all the difference. We prefer the laft, as
depending on fewer circumftances.
But all this inveftigation proceeds on the fuppofition
of equal gravity, whereas we know that the weight of a
particle of air decreafes as the fquare of its diflance from
the centre of the earth increafes. In order, therefore,
that a fuperior flratum may produce an equal preffure
at the furface of the earth, it mulf be denfer, becaufe a
particle of it gravitates lefs. The denfity, therefore, at
equal elevations, mull be greater than on the fuppofition
of equal gravity, and the law of diminution of denfity
muft be different.
Make OD : OA=OA : CV;
OC : OArciOA : Oc;
OB : OA=Q A : Ob ; &c. j
fo that Od, Oc, Ob, OA, may be reciprocals to OD,
OC, OB, OA} and through the points A, b, c, i/,draw
the perpendiculars AE, bf, eg, dh, making them pro¬
portional to the denfities in A, B, C, D : and let us
fuppofe CD to be exceedingly fmall, fo that the denfity
may be fuppofed uniform through the whole flratum.
Thus we have
OD x 0^=0 A*,=OC X Gr¬
and Oc : 0^=00 : OC j
and Oc : Oc—O d—OD : OD—OC,
or Oc : cd—OY) : DC ;
and cd :CDr=:Oc : OD;
•r, becaufe OC and OD are ultimately in the ratio of
equality, we have
cd: CD=Oe : OCrrOA* : OC1,
OA1 OA1
and c dA=CD X , and cdX cgz=. CD X ^ X
OA*
but CD X fff X pq-W is as the preffurc at C arifing from
the abfolute weight of the flratum CD. For this
weight is as the bulk, as the denfity, and as the gra¬
vitation of each particle jointly. Now CD exprefl'es
Oi\*
the bulk, eg the denfity, and the gravitation of
each particle. Therefore, cdX eg is as the preffure on
C arifing from the weight of the flratum DC ; but
cdX eg is evidently the element of the curvilineal area
ArnnE, formed by the curve Efg hn and the ordinates
AE, bf, eg, ah, &c. mn. Therefore the fum of all the
elements, fuch as c dhg, that is, the area cmng below
eg, will be as the whole preffure on C, arifing from the
gravitation of all the air above it; but, by the nature
of air, this whole preffure is as the denfity which it
produces, that is, as eg. Therefore the curve Egn is
of fuch a nature that the area lying below or beyond any
ordinate eg is proportional to that ordinate. This is the
property of the logarithmic curve, and E^n is a loga¬
rithmic curve.
333 But farther, this curve is the fame with EGN. For
let B continually approach to A, and ultimately coin¬
cide with it. It is evident that the ultimate ratio of
BA to Ab, and of BF to bf, is that of equality j and if
EFK, Yfk, be draivn, they will contain equal angles
with the ordinate AE, and will cut off equal fubtan-
gents AK, Ah. The curves EGN, Egn are therefore
the fame, but in oppofite portions.
Laflly, if OA, Ob, Oc Od, &c. be taken in arith- Height
metical progjreflion decreasing, their reciprocals OA, OB, ^ l|K^At'
OC, OD, &c. will be in harmonical progreflion increa-: ‘ ^ ^ y
fing, as is w*ell known : but, from the nature of the 233
logarithmic curve, when OA, Ob, Oc, Od, &c. are
in arithmetical progrefTxon, the ordinates AE, bf eg, dh,
&c. are in geometrical progreflion. Therefore when
OA, OB, OC, OD, &c. are in harmonical progrefiion,
the denfities of the air at A, B, C, D, &c. are in geo¬
metrical progrefiion j and thus may the denfity of the
air at all elevations be difeovered. Thus to find the
denfity of the air at K the top of the homogeneous at-
mofphere, make OK : OA—OA : OL, and draw the
ordinate LT, LT is the denfity at K.
The celebrated Dr Halley was the firft who obferved
the relation between the denfity of the air and the or¬
dinates of the logarithmic curve, or common loga¬
rithms. This he did on the fuppofition of equal gra¬
vity \ and his difeovery is acknowledged by Sir Ifaac
Newton in Frincip. ii. prop. 2 2. fchol. Halley’s difler-
tation on the fubjefl is in N° 185 of the Phil. Tranf.
Newton, wuth his ufual fagacity, extended the fame rela¬
tion to the true Hate of the cafe, where gravity is as
the fquare of the diftance inverfely j and thowed that
w-hen the diftances from the earth’s centre are in har¬
monic progrefiion, the denfities are in geometric pro-
greflion. He fhows indeed, in general, what progrefiion
of the diflance, on any fuppofition of gravity, wall
produce a geometrical progrefiion of the denfities, fo
as to obtain a fet of lines OA, Ob,Oc, Od, Sec. which
wall be logarithms of the denfities. The lubjedt was
afterwards treated in a more familiar manner by Cotes
in Ids Hydrqjl. LeB. and in his Harmonia Menfurarum;
alfo by Dr Brook Taylor, Meth. Increment.; Wolf in
his Aerometria ; Herman in his Phoranomic ; &c. Sec.
and lately by Horfley, Phil. Tranf. tom. Ixiv.
An important corollary is deducible from thefe prin-Tjie2a^r jias
ciples, viz. that the air has a finite denfity at an in- a gnite
finite diflance from the centre of the earth, namely, denlity at
fuch as -will be reprefented by the ordinate OP drawn ap infinite
through the centre. It may be objected to this con-^1^”^
clufion, that it would infer an infinity of matter in thecentre 0f
univerfe, and that it is inconfiflent with the phenomena the earth,
of the planetary motions, wrhich appear to be performed
in a fpace void of all refiflance, and therefore of all mat¬
ter. But this fluid mull be fo rare at great diftances,
that the refiftance will be infenfible, even though the
retardation occafioned by it has been accumulated for
ages. Even at the very moderate diftance of 500 miles,
the rarity is fo great that a cubic inch of common air
expanded to that degree would occupy a fphere equal to
the orbit of Saturn ; and the whole retardation which
this planet would fuftain after fome millions of years
would not exceed what w^ould be occafioned by its meet¬
ing one bit of matter of half a grain w-eight.
This being the cafe, it is not unreafonable to fuppofe
the vifible univerfe occupied by air, which, by its gra¬
vitation, ivill accumulate itfelf round every body in it,
in a proportion depending on their quantities of matter,
the larger bodies attrafling more of it than the fmaller
ones, and thus forming an atmofphere about each. And
many appearances warrant this fuppofition. Jupiter,
Mars, Saturn, and Venus, are evidently furrounded by
atmofpheres. The conftitution of thefe atmofpheres
may differ exceedingly from other caufes. If the pla-
Afmo- net has nothing on its fufface which can be diffolved
cf th^otLr^ ^le a‘r or volatilized by heat, the atmofphere will be
Planets continually clear and transparent, like that of the moon,
gcc. ’ Mars has an atmofphere which appears precifely like
—v—our own, carrying clouds, or depofiting fnow's: for
Th 23tmo v' ^en’ ^ t^e obliquity of his axis to the plane of his
fpherefof0* be turns his north pole towards the fun, it is
Mars. obferved to be occupied by a broad white fpot. As
the fummer of that region advances, this fpot gradually
wattes, and fometimes vanifhes, and then the fouth pole
comes in fight, furrounded in like manner with a white
fpot, which undergoes fimilar changes. This is precife¬
ly the appearance which the fnowy circumpolar regions
of this earth will exhibit to an aftronomer on Mars. It
may not, however, be fnow that we fee j thick clouds
will have the fame appearances.
©f Jupiter. The atmofphere of the planet Jupiter is alfo very
fimilar to our own. It is diverfified by ftreaks or belts
parallel to his equator, which frequently change their
appearance and dimenfions, in the fame manner as thofe
tracks of fimilar Iky which belong to different regions
of this globe. There is a certain kind of weather that
more properly belongs to a particular climate than to
any other. This is nothing but a certain general date
of the atmofphere which is prevalent there, though
with confiderable variations. This muff appear to a
fpeclator in the moon like a ftreak fpread over that
climate, diftinguilhing it from others. But the moll:
remarkable fimilarity is in the motion of the clouds on
Jupiter. They have plainly a motion from eaft to WTeft
relative to the body of the planet: for there is a re¬
markable fpot on the furface of the planet, which is
obferved to turn round the axis in 9I1. 51' 16"; and
there frequently appear variable and perilhing fpots in
the belts, which fometimes lalt for feveral revolutions.
Thefe are obferved to circulate in 9. 55. 05. Thefe
numbers are the refults of a long feries of oblervations
by Dr Herfchel. This plainly indicates a general cur¬
rent of the clouds w’effward, precifely fimilar to wdiat
a fpeilator in the moon muff obferve in our atmofphere
arifing from the trade-winds. Mr Schroeter has made
the atmofphere of Jupiter a ftudy for many years ; and
deduces from his obfervations that the motion of the va¬
riable fpots is fubjeft to great variations, but is always
from call to wreft. This indicates variable winds.
Of Venus. The atmofphere of Venus appears alfo to be like
ours, loaded w ith vapours, and in a ftate of continual
change of abforption and precipitation. About the
middle of the 17th century the furface of Venus wras pretty
diftin&ly feen for many years chequered writh irregular
fpots, w'hich are deferibed by Campani, Bianchini, and
other aftronomers in the fouth of Europe, and alfo by
Caffmi at Paris, and Plooke and Townley in England.
But the fpots became gradually more faint and indi-
ftinft j and, for near a century, have difapneared. The
whole furface appears now of one uniform brilliant
white. The atmofphere is probably filled with a refledf-
ing vapour, thinly diffufed through it, like water faint¬
ly tinged with milk. A great depth of this muff ap¬
pear as white as a finall depth of milk itfelf j and it
appears to be of a very great depth, and to be refrac¬
tive like our air. For Dr Herfchel has obferved, by
the help of his fine telefcopes, that the illuminated
part of Venus is confiderably more than a hemifphere,
and that the light dies gradually away to the bounding
VOL. XVI. Part II. 6
PNEUMATICS. 705
This is the very appearance that the earth Atmo-
margm.   _ . . ^ j t    .
wrould make if furnifhed with fuch an atmofphere. The -*t^er^cr
boundary of illumination would have a penumbra reach- 1 arrj.s
ing about nine degrees beyond it. If this be the con- &c.
ftitution of the atmolphere of Venus, (he may be inha-1—^—v 
bited by beings like ourfelves. They would not be
dazzled by the intolerable fplendor of a fun four times
as big and as bright, and fixteen times more glaring,
than ours: for they wmuld feldom or never fee him, but
inftead of him an uniformly bright and white Iky. They
would probably never fee a ftar or planet, unlefs the
dog-ftar and Mercury •, and perhaps the earth might
pierce through the bright haze which furrounds their
planet. For the fame reafon the inhabitants would not
perhaps be incommoded by the fun’s heat. It is in¬
deed a very queftionable thing, whether the fun would
caufe any heat, even here, if it were not for the chemi¬
cal a&ion of his rays on our air. This is rendered not
improbable by the intenfe cold felt on the tops of the
higheft mountains, in the cleared air, and even under a
vertical fun in the torrid zone. 238
The atmofphere of comets feems of a nature totally of c0*
different. This feems to Ke of inconceivable rarity,mets'
even when it reflefts a very fenfible light. The tail is
always turned nearly away from the fun. It is thought
that this is by the impulfe of the folar rays. If this
be the cafe, we think it might be difeovered by the
aberration and the refraction of the light by which wre
fee the tail : for this light muff come to our eye with
a much fmaller velocity than the fun’s light, if it be
reflected by repulfive or elaftic forces, which there is
every reafon in the wmrld to believe 5 and therefore the
velocity of the reflected light will be diminiflied by all
the velocity communicated to the reflecting particles.
This is almoft inconceivably great. The comet of 1680
w^ent half round the fun in ten hours, and had a tail at
leaft a hundred millions of miles long, which turned
round at the fame time, keeping nearly in the direction
oppofite to the fun. The velocity neceffary for this is
prodigious, approaching to that of light. And perhaps
the tail extends much farther than we fee it, but is vi-
fible only as far as the^ velocity with which its particles
recede from the fun is lefs than a certain quantity,
namely, what would leave a fufficient velocity for the,
reflected light to enable it to affeCt our eyes. And it
may be demondrated, that although the real form of
the vifible tail is concave on the anterior fide to which
the comet is moving, it may appear convex on that
fide, in confequence of the very great aberration of the
light by which the remote parts are feen. All this
may be difeovered by properly contrived obfervations ;
and the conjeCture merits attention. But of this digref-
fion there is enough j and we return to our fubjeft, the
conditution of our air.
We have drown how to determine a priori the denfi-The baro-
ty of the air at different elevations above the furface ofmeter ufe<i
the earth. But the denfities may be difeovered in allm .takinS
acceflible elevations by experiments; namely, by ob-heishtS‘
ferving the. heights of the mercury in the barometer.
This is a direCt meafure of the preffure of the incum¬
bent atmofphere ; and this is proportional to the denfity
which it produces.
Therefore, by means of the relation fubfiding between 24®
the. denfities and the elevations, wre can difeover the ele¬
vations by obfervations made on the denfities by means
4U 0f
7o6 P N E U M
Barometer, of the barometer j and thus we may meafure elevations
‘ “Y-” ' by means of the barometer j and, with very little trou¬
ble, take the level of any extenfive track of country.
Of this we have an illuftrious example in the fedlion
which the Abbe Chappe D’Auteroche has given of the
whole country between Breft and Ekaterineburgh in
Siberia. This is a fubject which deferves a minute con-
fideration : we lhall therefore prefent it under a very
limple and familiar form ; and trace the method through
its various fteps of improvement by De Luc, Key, Shuck-
241 burgb> &c-
Explan a- We have already obferved, oftener than once, that if
tion ol its the mercury in the barometer Hands at 30 inches, and if
afe. Sec. j-fog ajr ancj mercury be of the temperature 3 2° in Fah¬
renheit’s thermometer, a column of air 87 feet thick
has the fame weight with a column of mercury ^ 0f an
inch thick. Therefore, if we carry the barometer to a
higher place, fo that the mercury finks to 29.9, we have
afeended 87 feet. Nowr, fuppofe we carry it Hill higher,
and that the mercury Hands at 29.8; it is required to
know what height we have nowr got to ? We have evi¬
dently afeended through another flratum of equal weight
with the former: but it mufl be of greater thicknefs,
becaufe the air in it is rarer, being lefs compreffed. We
may call the denlity of the firfl flratum 300, meafuring
the denfity by the number of tenths of an inch of mercu¬
ry which its elaflicity proportional to its denfity enables
it to fupport. For the fame reafon, the denlity of the
fecond Hratum mufl be 299 : but when the weights are
equal, the bulks are inverfely as the denfities j and when
the bafes of the ftrata are equal, the bulks are as the
thicknefles. Therefore, to obtain the thicknefs of this
fecond ftratum, fay 299 :300=87 : 87.29 5 and this fourth
term is the thicknefs of the fecond ftratum, and we have
afeended in all 174.29 feet. In like manner we may rife
till the barometer Ihows the denfity to be 298 : then fay,
298 : 30=87 : 87.584 for the thicknefs of the third
ftratum, and 261,875 or 261^ for the whole afeent 5
and we may proceed in the fame way for any num¬
ber of mercurial heights, and make a table of the corre-
fponding elements as follows : Where the firft column is
the height of the mercury in the barometer, the fecond
column is the thicknefs of the ftratum, or the elevation
above the preceding ftation j and the third column is
the whole elevation above the firft ftation.
042
Bar. Strat. Elev.
30 00.000 00.000
29.9 87.OOO 87.OOO
29.8 87.291 174.291
29.7 87.584 261.875
29.6 87.879 349-754
29,5 88.176 437-93°
29.4 88.475 526.405
29.3 88.776 615.181
29.2 89.079 704.260
29.1 89.384 793.644
29 89.691 883.335
Having done this, we can now meafure any elevation
within the limits of our table, in this manner.
Obferve the barometer at the lower and at the upper
ftations, and write down the correfponding elevations.
Subtract the one from the other, and the remainder Is
the height required. Thus fuppofe that at the lower
A T I C S.
ftation the mercurial height was 29.8, and that at the
upper ftation it was 29.1.
29.1 793-644
29.8 174.291
6I9-353 = Elevation,
We may do the fame tiling •with tolerable accuracy
without the table, by taking the medium nt of the mer¬
curial heights, and their difference d in tenths of an inch j
and then lay, as m to 300, fo is 87^ to the height re-
300X87^ 26100*/ , , .
quired//.- or n —    . Ihus, in the
ni m
foregoing example, m is 294.5, anc^ d\s—*]) and there¬
fore h = ~~:= 620.4, differing only one foot from
the former value.
Either of thefe methods is fufficiently accurate for
moft purpofes, and even in very great elevations will not
produce any error of confequence: the whole error of
the elevation 883 feet 4 inches, which is the extent of
the above table, is only £ of an inch.
But we need not confine ourfelves to methods of ap¬
proximation, when we have an accurate and fcientific
method that is equally eafy. We have feen that, upon
the fuppofition of equal gravity, the denfities of the air
are as the ordinates of a logarithmic curve, having the
line of elevations for its axis. We have alfo feen that,
in the true theory of gravity, if the diftances from the
centre of the earth increafe in a harmonic progreflion, the
logarithm of the denfities will decreafe in an arithmeti¬
cal progreflion j but if the greatefl: elevation above the
furface be but a few miles, this harmonic pregreflion
will hardly differ from an arithmetical one. Thus, if
Ab, Ac, Ad, are I, 2, and 3 miles, we ftiall find that
the correfponding elevations AB, AC, AD are fenfibly
in arithmetical progreffion alfo ; for the earth’s radius
AC is nearly 40c o miles. Hence it plainly follows^
that BC—AB is ^ , or ——   of a mile,
4000 X 4001 16004000
or of an inch j a quantity quite infignificant. We
may therefore affirm without hefitation, that in all ac-
ceffible places, the elevations increafe in an arithmetical
progreffion, while the denfities decreafe in a geometrical
progreffion. Therefore the ordinates are proportional
to the numbers which are taken to meafure the denfities,
and the portions of the axis are proportional to the lo¬
garithms of thefe numbers. It follows, therefore, that
we may take fuch a fcale for meafuring the denfities
that the logarithms of the numbers of this fcale ffiall be
the very portions of the axis j that is, of the vertical line
in feet, yards, fathoms, or what meafure we pleafe : and
we may, on the other hand, choofe fuch a fcale for mea¬
furing our elevations, that the logarithms of our fcale of
denfities ffiall be parts of this fcale of elevations j and we
may find either of thefe feales fcientifically. For it is a
known property of the logarithmic curves, that when the
ordinates are the fame, the intercepted portion of the
abfciffse are proportioned to their fubtangents. Now we
know the fubtangent of the atmofpherieal logarithmic ;
it is the height of the homogeneous atmofphere in any
meafure w-e pleafe, fuppofe fathoms : we find this height
by comparing the gravities of air and mercury, when
both
245
I
I
P N £ U M
Barometer. totK are of fome determined denuty. Thus, in the
temperature of 3 2° of Fahrenheit’s thermometer, when
the barometer ftands at 30 inches, it is known (by many
experiments) that mercury is 10423.068 times heavier
than air \ therefore the height of the balancing column
of homogeneous air will be 10423.068 times 30 inches j
that is, 4342.945 Englilh fathoms. Again, it is known
that the fubtangent of our common logarithmic tables,
where 1 is the logarithm of the number 10, is 0.4342945.
Therefore the number 0.4342945 is to the difference
D of the logarithms of any two barometric heights as
4342.945 fathoms are to the fathoms F contained in
the portion of the axis of the atmofpherical logarith¬
mic, which is intercepted between the ordinates equal
to thefe barometrical heights j or that 0.4342945 : D
—4342-945 : and 0.4342,945 : 4342.945=0 : Fj
but 0.4342945 is the ten-thoufandth part of 4342.945,
and therefore D is the ten-thoufandth part of F.
*•44 And thus it happens, by mere chance, that the loga¬
rithms of the denfities, meafured by the inches of mer¬
cury which their elafticity fupports in the barometer,
are juft the ten-thoufandth part of the fathoms con¬
tained in the correfponding portions of the axis of the
atmofpherical logarithmic. Therefore, if we multiply
our common logarithms by 10000, they will exprefs the
fathoms of the axis of the atmofpherical logarithmic; no¬
thing is more eafily done. Our logarithms contain what
is called the index or charafleriftic, which is an integer
and a number of decimal places. Let us juft remove
the integer-place four figures to the right hand : thus
the logarithm of 60 is 1.7781513, which is one integer
and Multiply this by 10.000, and we ob-
I0000000
tain —17781. C13, or 17781
1001 ' J 1000
The practical application of all this reafoning is ob¬
vious and eafy : obferve the heights of the mercury in
the barometer at the upper and lower ftations in inches
and decimals j take the logarithms of thefe, and fub-
tradt the one from the other : the difference between
them (accounting the four firft decimal figures as inte¬
gers) is the difference of elevation of fathoms.
Example.
Merc. Height at the lower ftation
upper ftation
707
Taking
heights;
*45
29.8
29.I
Diff. of Log. x 10000
233
1.4742163
1.463893°
0.0103.233
or 103 fathoms and of a fathom, which is 619.392
1000
feet, or 619 feet ^ inches; differing from the approxi-
mated value formerly found about 4 an inch.
This me- Such is the general nature of the barometric meafure-
thod of ment of heights firft fuggefted by Dr Halley ; and it has
measuring been verified by numberlefs comparifons of the heights
how much calcidated in this way with the fame heights meafured
improved, geometrically. It was indeed in this tvay that the pre-
cife fpecific gravity of air and mercury was moft accu¬
rately determined ; namely, by obferving, that when the
temperature of air and mercury was 32, the difference
of the logarithms of the mercurial heights were precife-
ly the fathoms of elevation. But it requires many cor-
A T I c S.
reftions to adjuft this method 16 the circUmftanceb of
the cafe ; and it was not till very lately that it has been
fo far adjufted to them as to become ufeful. We are
chiefly indebted to Mr de Luc for the improvements.
The great elevations in Switzerland tenabled him to
make an immenfe number of obfervations, in almoft
every variety of circumftances. Sir George Shuckburgh
alfo made a great number with moft accurate inftruments
in much greater elevations, in the fame country j and 1&
made many chamber experiments for determining the
laws of variation in the fubordinate circumftances. Ge¬
neral Roy alfo made many to the fame purpofe. And
to thefe two gentlemen we are chiefly obliged for the
corre&ions which are now generally adopted.
It is eafy to perceive that the method, as already depends
expreffed, cannot apply to every cafe: it depends on on the
the fpecific gravity of air and mercury, combined withhieciSc gf*"
the fuppofition that this is affected only by a change mcr '
prejjhre. But fince all bodies are expanded by heat, cCly
and as there is no reafon to fuppofe that they are equal¬
ly expanded by it, it follows that a change of tempera¬
ture will change the relative gravity of mercury and
air, even although both fuffer the fame change of tem¬
perature : and fince the air may be warmed or cooled
w-hen the mercury is not, or may change its tempera¬
ture independent of it, wx may expecl ftill greater vari¬
ations of fpecific gravity.
The general effeft of an augmentation of the fpecific
gravity of the mercury muft be to increafe the fubtan¬
gent of the atmofpherical logarithmic j in which cafe the
logarithms of the denfities, as meafured by inches of
mercury, wrill exprefs meafures that are greater than fa¬
thoms in the fame proportion that the fubtangent is in-
creafed j or, when the air is more expanded than the
mercury, it wall require a greater height of homogene¬
ous atmofphere to balance 30 inches of mercury, and a
given fall of mercury will then correfpond to a thicker
ftratum of air.
In order, therefore, to perfeft this method, we muft
learn by experiment how much mercury expands by an
increafe of temperature j we muft tdfo learn how much
the air expands by the fame, or any change of tempera¬
ture ; and how much its elafticity is affe&ed by it. Both
thefe circumftances muft be confidered in the cafe of
air 5 for it might happen that the elafticity of the air is
not fo much affefled by heat as its bulk is.
It will, therefore, be proper to ftate in this place the
experiments which have been made for afeertaining
thefe two expanfions.
The moft accurate, and the beft adapted experiments General
for afeertaining the expanfion of mercury, are thofe of Roy’s ex-
General Roy, publiftied in the 67th volume of the Phi-Peiiments
lofophical Tranfaftions. He expofed 30 inches of mer-on d’e
cury, actually fupported by the atmofphere in a baro- J^ercurj0
meter, in a nice apparatus, by which it could be made
of one uniform temperature through its whole length j
and he noted the expanfion of it in decimals of an inch.
Thefc are contained in the following table ; where the
firft column expreffes the temperature by Fahrenheit’s
thermometer, the fecond column expreffes the bulk of
the mercury, and the third column the expanfion of an
inch of mercury for an increafe of one degree in the ad¬
joining temperatures.
4 U .2
Table
w ■<t
oB
arometer. -
PNEUMATICS.
Table A.
Temp. Bulk of §
21 2‘
202
I92
182
I72
162
^2
I42
I32
122
112
102
92
82
72
62
52
42
32
22
12
2
0
30.4888
30.4652
30.4409
30-4159
30.3902
3°-3638
3°-3367
30.3090
30.2807
30.2518
30.2223
30.1922
30.1615
30.1302
30.0984
30.0661
32-0333
30.0000
29.9662
29-93 T9
29.8971
29.8901
Expan. for ic
O.OOOO763
O.OOOO787
O.OOOoSlO
O.OOO0833
O.COOC857
O.COO0880
O.OOOO903
O.OOOO923
O.OOOO943
O.OOOO963
O.OOOO983
O.OOOIOO3
O.OOOIO23
O.OOOIO43
O.OOOI063
O.OOOIO77
O.OOOIO93
0.0001 I 10
O.OOCII27
0.0001143
0.0001160
o.ooooi 77
249 This table gives rife to fome reflexions. The fcale
of the thermometer is conftruXed on the fuppofition
that the fucceflive degrees of heat are meafiired by
equal increments of bulk in the mercury of the ther¬
mometer. How comes it, therefore, that this is not ac¬
companied by equal increments of bulk in the mercury
of the column, but that the correfponding expanfions
of this column do continually diminifti: General Roy
attributes this to the gradual detachment of elaftic mat¬
ter from the mercury by heat, which preffes on the top
of the column, and therefore Ihortens it. He applied
a boiling heat to the vacuum a-top, without producing
any farther depreflion j a proof that the barometer had
been carefully filled. It had indeed been boiled through
its whole length. He had attempted to meafure the
mercurial expanfion in the ufunl way, by filling 30
inches of the tube with boiled mercury, and expofing it
to the heat with the open end uppermoit. But here it
is evident that the expanflon of the tube, and its folid
contents, muft be taken into the account. The expan¬
fion of the tube was found fo exceedingly irregular,
and fo incapable of being determined with precifion
for the tubes w'hich were to be employed, that he was
obliged to have recourfe to the method with the real
barometer. In this no regard wTas necelfary to any
circumftance but the perpendicular height. There was,
befides, a propriety in examining the mercury in the
very condition in which it was ufed for meafuring the
preflure of the atmofphere ; becaufe whatever compli¬
cation there was in the refults, it w-as the fame in the
barometer in aXual ufe.
iro The mofl obvious manner of applying thefe experi¬
ments on the expanfion of mercury to our purpofe, is to
reduce the obferved height of the mercury to what it
would have been if it were of the temperature 32.
Thus, fuppofe that the obferved mercurial height is
29.2, and that the temperature of the mentnry is 7'2®, Taking
make 30.1302 : 30=29.2 : 29.0738. This will be heights,
the true meafure of the denfity of the air of the flan- " ~"v
dard temperature. In order that we may obtain the
exaX temperature of the mercury, it is proper that
the obfervation be made by means of a thermometer at¬
tached to the barometer-frame, fo as to wTarm and cool
along w-ith it.
Or, this may be done without the help of a table, t^i
and with fufficient accuracy, from the circumltance
that the expanfion of an inch of mercury for one degree
diminifhes very nearly y^Q-th part in each lucceeding de¬
gree. If therefore we take from the expanfion at 32°
its thoufandth part for each degree of any range above
it, we obtain a mean rate of expanfion for that range..
If the obferved temperature of the mercury is below
3 2°, wre mull add this correction to obtain the mean ex¬
panfion. This rule will be made more exaX if we fup¬
pofe the expanfion at 32° to be =0.0001127. Then
multiply the obferved mercurial height by this expan¬
fion, and we obtain the correction, to be fubtraXed or
added according as the temperature of the mercury was
above or below 32°. Thus to abide by the former ex-,
ample of 72°. This, exceeds 32° by 40 : therefore take
40 from 0.0001127, and we have 0.0001087 for the
medium expanfion for that range. Multiply this by 40,
and we have the whole expanfion of one inch of mercu¬
ry, =0.004348. Multiply the inches of mercurial height,
viz. 29.2 by this expanfion, and we have for the correc¬
tion 0.12696 which being fubtraXed from the oblerv-
ed height leaves 29.07304, disTering from the accurate
quantity lefs than the thoufandth part of an inch. T his
rule is very eafily kept in the memory, and fuperfeues
the ufe of a table.
This correXion may be made with all neceflary ex- 2?2
aXnefs by a rule Hill more liniple 4 namely, by multi¬
plying the obferved height of the mercury by the dif¬
ference of its temperature from 32°, and cutting off
four cyphers before the decimals ot the mercurial height.
This will feldom err of an inch. We even believe
that it is the moll exaX method within the range of
temperatures that can be expeXed to occur in meafuring^
heights: for it appears, by comparing many experiments
and obfervations, that General Roy’s meafure of the
mercurial expanfion is too great, and that the expanfion
of an inch of mercury between 20° and 70° of Fahren¬
heit’s thermometer does not exceed 0.000102 per de¬
gree. Having thus correXed the obferved mercurial
heights by reducing them to what they would have been
if the mercury had been of the ftandard temperature,
the logarithms of the correXed heights are taken, and
their difference, multiplied by 10000, will give the dif¬
ference of elevations in Englifh fathoms.
There is another way of applying this correXion, ful- 253
ly more expeditious and equally accurate. The differ¬
ence of the logarithms of the mercurial heights is the
meafure of the ratio of thofe heights. In like manner
the difference of the logarithms of the obferved and cor¬
reXed heights at any ftation is the meafure of the ratio
of thofe heights. Therefore this lalt difference of the
logarithms is the meafure of the correXion of this ratio.
Now the obferved height is to the correXed height
nearly as 1 to 1.000102. The logarithm of this ratio,
or the difference of the logarithms of 1 and 1.000102,
is 0.0000444. This is the correXion for each degree
that
PNEUMATICS.
7C9
Barometer tliat the temperature of the mercury differs from 32.
' v 1 Therefore multiply 0.0000444 by the difference of the
mercurial temperatures from 32, and the products will
be the corrections of the refpeCtive logarithms.
254 Bat there is ftill an eafier way of applying the lo¬
garithmic correction. If both the mercurial tempera¬
tures are the fame, the differences of their logarithms
will be the fame, although each may be a good deal
above or below the ftandard temperature, if the expan-
fion be very nearly equable. The correction will be
neceffary only when the temperatures at the two fta-
tions are different, and wall be proportional to this dif¬
ference. Therefore, if the difference of the mercurial
temperatures be multiplied by 0.0000444, the produCt
will be the correction to be made on the difference of
the logarithms of the mercurial heights.
But farther, fince the differences of the logarithms
of the mercurial heights are alfo the differences of ele¬
vation in Englifh fathoms, it follows that the correc¬
tion is alfo a difference of elevation in Englifh fathoms,
or that the correction for one degree of difference of
mercurial temperature is of a fathom, or 3 2 inches,
or 2 feet 8 inches.
This correction of 2.8 for every degree of difference
of temperature muff be fubtraCted from the elevation
found by the general rate, when the mercury at the up¬
per ftation is colder than that at the lower. For when
this is the cafe, the mercurial column at the upper fta¬
tion will appear too ftiort, the preffure of the atmofphere
too fmall, and therefore the elevation in the atmofphere
will appear greater than it really is.
255 Therefore the rule for this correClion will be to mul¬
tiply 0.0000444 by the degrees of difference between
the mercurial temperatures at the two ftations, and to
add or fubtraCt the produCl from the elevation found by
the general rule, according as the mercury at the upper
ftation is hotter or colder than at the lower.
256 If the experiments of General Roy on the expanfion
of the mercury in a real barometer be thought moft. de-
ferving of attention, and the expanfton be confidered as
variable, the logarithmic difference correfponding to this
expanfton for the mean temperature of the two barome¬
ters may be taken. Thefe logarithmic differences are
contained in the following table, which is carried as far
as 1120, beyond which it is not probable that any ob-
fervations will be made. The number for each tempera¬
ture is the difference between the logarithms of 30 inches
of the temperature 32, and of 30 inches expanded by
that temperature.
Tabee B.
Log. diff.
Dec. of
Fath.
112W
102
92
82
72
62
52
42
32
O.OOOO427
©.OOOO436
O.OOOO444-
O.OOOO453
O.OOOO460
O.OOOO468
0:0000475
O.OOOO482
O.OOOO489
O.OOOO497
O.OOOO504
.427
•436
•444
•453
.460
.468
•475
.482
.489
•497
•504
2- 7
2.7
2i8
2.9
2.9
2.10
2.10
2.11
2.11
3- o
3-°
It is alfo neceffary to attend to the temperature-of Faking
the air 5 and the change that is produced by heat in its , >
denfity is of much greater confequence than that of the ” ^
mereuxy. The relative gravity of the two, on which yhe tem-
the fubtangent of the logarithmic curve depends, andperature of
confequently the unit of our fcale of elevations, is much;1*16 air mu^
more affeded by the heat of the air than by the heat of^^
the mercury.
This adjuftment is of incomparably greater difficulty;
than the former, and we can hardly hope to make it
perfeft. We thall narrate the chief experiments which
have been made on the expanfion of air, and deduce
from them luch rules as appear to be neceffary confe-
quences of them, and then notice the circumftances
which leave the matter ftill imperfed. 21.3
General Roy compared a mercurial and an air ther-Compari-
mometer, each of which was graduated arithmetically, fon of a
that is, the units of the feales were equal bulks of mer- ™edrc“fial
cury, and equal, bulks (perhaps different from the for- t}jer(QQme,
mer) of air.. He found their, progrefs as in the follow-^er.
ing table.
Table C.
It has been eftabliftied by many experiments that
equal increments of heat produce equal increments in 2^9
the bulk of mercury. The differences of temperature
are therefore expreffed by the fecond column, and may
be confidered as equal; and the numbers of the thiid
column muft be allowed to exprefs the fame tempera¬
tures with thofe of the firft. They dire&ly exprefs the
bulks of the air, and the numbers of the fourth column
exprefs the differences of thefe bulks. Thefe are evi¬
dently unequal, and fhow that common air expands moft
of all when of the temperature 62 nearly. 2^0
The next point was to determine what was the a&ualTo detc
increafe of bulk by fome known increafe of heat. Fornua
this purpofe he took a tube, having a narrow bore, and
a ball at one end. He msafured with great care the bulk from
capacity of both the ball and the tube, and divided the a known
tube into equal fpaces which bore a determined pro-increafe
portion to the capacity of the ball. This apparatusheat*
was fet in a long cylinder filled with frigorific mixtures
or with water, which could be uniformly heated up to
the boiling temperature, and was accompanied by a nice
thermometer. The expanfion of the air was meafured
by means of a column of mercury which rofe or funk in
the tube. The tube being of a fmall bore, the mercu¬
ry did not drop out of it; and the bore being chofen
as equable as poflible, this column remained of an uni¬
form length, whatever part of the tube it chanced to
occupy. By this contrivance he was able to examine
the
7io P N E U M
Barometer, the expansibility of air of various denfities. When the
v~ column of mercury contained only a Single drop or two,
the air was nearly of the denfity of the external air. If
he w'ifhed to examine the expansion of air twice or thrice
as denfe, he ufed a column of 30 or 6<3 inches long 5
and to examine the expanfion of air that is rarer than
the external air, he placed the tube with the ball upper-
xnoft, the open end coming through a hole in the bot¬
tom of the veffel containing the mixtures or water. By
this pofition the column of mercury was hanging in the
tube, fupported by the preffure of the atmofphere j and
the elafticity of the included air was meafured by the
difference between the fufpended column and the com¬
mon barometer.
261 The following table contains the expanfion of 1000
parts of air, nearly of the common denfity, by heating it
from o to 212. The firft column contains the height
of the barometer ; the fecond contains this height aug¬
mented by the fmall column of mercury in the tube of
the manometer, and therefore expreffes the denfity of
the air examined j the third contains the total expan¬
fion of 1000 parts j and the fourth contains the expan¬
fion for i°, fuppofing it uniform throughout.
Table D.
262
Denfity
of Air
examined.
Expanfion
of 1000 pts
by 2120.
Expanfion
by 1°.
29- 95
30- °7
29.48
29.90
29.96
29.90
29-95
30.07
29.48
3I-52
3°-77
29.90
30-73
30.92
30-55
30.60
30.60
30.00
483.89
482.10
-480.74
485.86
489.45
476.04
4^7*55
482.80
489.47
2.2825
2.2741
2.2676
2.2918
2.2087
2.2455
2.2998
2.2774
2.3087
Mean
30.62 484.21 2.2840
Hence it appears, that the mean expanfion of 1000
parts of air of the denfity 30.62 by one degree of Fah¬
renheit’s thermometer is 2.284, or that 1000 becomes
1002.284.
If this expanfion be fuppofed to follow the fame rate
that was obferved in the comparifon of the mercurial and
air thermometer, we (hall find that the expanfion of a
thoufand parts of air for one degree of heat at the differ¬
ent intermediate temperatures will be as in the follow¬
ing table.
Table E.
Temp.
Total
Expanfion.
Expanfion
for i°.
Temp.
Total
Expanfion.
Expanfion
for i°.
212
I92
172
* 52
I32
112
92
82
72
484.210
444.OI I
402.452
359-5°3
269.513
222.006
I97-795
172.671
2.0099
2.0080
2-,475 L
2.2155
£.2840
2-3754
2.4211
2.5124
172.671
147.090
121.053
95-929
71.718
48.42r
26.038
2.5581
2.6027
2.5124
2.4211
2.3297
2.2583
j 2.1698
A T I G S.
If we would have a mean expanfion for any pavticu- Tahm*
lar range, as between 12° and 9 2°, which is the moil i heights,
likely to comprehend all the geodsetical obfervations,
we need only take the difference of the bulks 26.038
and 222.006.= 195.968, and divide this by the inter¬
val of temperature 8o°, and we obtain 2.4496, or 2.45
for the mean expanfion for i°.
It would perhaps be better to adapt the table to a ,
mafs of 1000 parts of air of the ftandard temperature v
3 2° j for in its prefent form it (hows the expanfibility
of air originally of the temperature o. This will be
done with fufficient accuracy by faying (for 212°)
1071.718 ; 1484.210=1000. : 13849, and fo of the
reft. Thus we ftiall conftrufl the following table of the
expanfion of 10,000 parts of air.
Table F.
This will give for the mean expanfion of 1000 parts
of air between 120 and 92 = 2.29.
Although it cannot happen that in meafuring the 2<J4
differences of elevation near the earth’s furface, we (hall
have occafion to employ air greatly exceeding the com- penments
mon denfity, we may infert the experiments made by on air
General Roy on fuch airs. They are expreffed in the above thtf
following table $ where column firft contains the den- n
fities meafured by the inches of mercury that they will ’
fupport when of the temperature 3 2° : column fecond is
the expanfion of 100© parts of fuch air by being heated
from o to 212 j and column third is the mean expan¬
fion for 1°.
Mean
Table G.
Denfity. E?Panfi'jn EXpanf.
for 2i«. tor
JOI.7
92.3
80.5
54-5
49-7
75-7
45I-54
423-23
412.09
439-87
443.24
434
2.130
1.996
1.944
2.075
2.091
2-Q47
iG$
We have much more frequent occafion to operate in And on ait
air that is rarer than the ordinary ftate of the fuperficialbtl0™ tbat
atinofphere.denfity*
4
P N E U M
General Roy accordingly made many ex-
Barometer, atmofphere.
' v ' periments on fuch airs. He found in'"general, that "their
expanfibility by heat was analogous to that of air in its
ordinary deniity, being greatel! about the temperature
6o°. He found, too, that its expanlibility by heat di-
miniflied with its deniity, but he could not determine
the law of gradation. When reduced to about one-fifth
of the denfity of common air, its expanfion was as fol¬
lows.
Table H.
A T I C S.
ftratum wdiere the barometer Hands at ^
Temp.
Bulk.
Difference.! Expanfion
for i°.
212
I92
172
I52
132
112
92
72
52
32
1141.504
1134>429
1122.165
1108.015
1093.864
ig79.636
1064.699
1043.788
1017.845
1000.000
7-075
12.264
14-150
I4-I51
14.228
14-937
20.911
25-943
I7-^45
266
Air of or¬
dinary den
fity ex¬
pands moft,
&c.
Mean expanfion
0-354
0.613
0.708
0.708
0.711
0.747
1.045
x.297
0.892
0.786
267
The height
which
produces
a given fall
in the ba¬
rometer,
increafes
with the
air’s expan¬
fion.
From this very extenfive and judicious range of ex¬
periments, it is evident that the expanfibility of air by
heat is greateft when the air is about its ordinary den¬
fity, and that in fmall denlities it is greatly diminilhed.
It appears alfo, that the law of compreffion is altered }
for in this fpecimen of the rare air half of the whole ex¬
panfion happens about the temperature 990, but in air
of ordinary denfity at 105°. This being the cafe, we
fee that the experiments of Mr Amontons, narrated in
the Memoirs of the Academy at Paris 1702, &c. are
not inconfifient with thofe more perfpicuous experiments
of General Roy, Amontons found, that whatever was
the denfity of the air, at leaft in cafes much denfer
than ordinary air, the change of 18o° of temperature
increafed its elafticity in the fame proportion : for he
found, that the column of mercury which it fupported
when of the temperature 50, wras increafed one-third at
the temperature 212. Hence he haftily concluded, that
its expanfibility was increafed in the fame proportion ;
but this by no means follows, unlefs w-e are certain that
in every temperature the elafticity is proportional to the
denfity. This is a point which ftill remains undecided 5
and it merits attention, becaufe if true it eftablilhes a
remarkable law concerning the aftion of heat, which
would feem to go to prove that the elafticity of fluids
is the property of the matter of fire, which it fuper-
mduces on every body with which it combines in the
form of vapour.
After this account of the expanfion of air, w-e fee
that the height through w-hich w-e mull rife in order to
produce a given fall of the mercury in the barometer, or
the thicknefs of the ftratum of air equiponderant with a
tenth of an inch of mercury, muft increafe with the ex¬
panfion or air 5 and that if — be the expanfion for
1000 r
one degree, we muft multiply the excefs of the tempera¬
ture of the air above 32° by 0.00229, an(* multiply the
product by 87, in order to obtain the thicknefs of the
26S
-- ^o inches: or
whatever be the elevation indicated by the difference of
the barometrical heights, upon the fuppofition that the
air is of the temperature 3 2°, we muft multiply this by
0.00229 f°r every degree that the air is warmer or
colder than 32. The product muft be added to the
elevation in the firft cafe, and fubtrafled in the latter.
Sir George Shuckburgh deduces 0.0024 from his
experiments as the mean expanfion of air in the ordinary
cafes : and this is probably nearer the truth ; becaule
General Roy’s experiments w-ere made on air which w-as
freer from damp than the ordinary air in the fields : and
it appears from his experiments, that a very minute quan¬
tity of damp inereafes its expanfibility by heat in a pro¬
digious degree.
The great difficulty is how to apply this corre&ion ; Difficulties
or rather, how to determine the temperature of the air in this
in thole extenfive and deep ftrata in which the elevations mode of
are meafured. It feldom or never happens that the ftra-me.a,}innS
turn is of the fame temperature throughout. It is com- els tS*
monly much colder aloft 5 it is alfo of different conftitu-
tions. Below it is warm, loaded with vapour, and very
expanfible ; above it is cold, much drier, and lets ex-
panfible, both by its drynefs and its rarity. The cur¬
rents of wind are often difpofed in ftrata, w-hich long
retain thei-r places; and as they come from different re¬
gions, are of different temperatures and different confti-
tutions. We cannot therefore determine the expanfion
of the whole ftratum with precifion, and muft content
ourfelves w-ith an approximation : and the bell approxi¬
mation that we can make is, by fuppofing the whole
ftratum of a mean temperature between thofe of its up¬
per and lower extremity, and employ the expanfion cor-
refponding to that mean temperature.
1 his, however, is founded on a gratuitous fuppofition,
that the whole intermediate ftratum expands alike, and
that the expanfion is equable in the different interme¬
diate temperatures; but neither of thefe is warranted
by experiment. Rare air expands lefs than what is
denfer j and therefore the general expanfion of the whole
ftratum renders its denfity more uniform. Dr Hcrfley
has pointed out fome curious confequences of this in
Phil. Tranf. vol. Ixiv. There is a particular eleva¬
tion at which the general expanfion, inftead of diminifh-
ing the denfity of the air, increafes it by the iuperior
expanfion of what is below; and we know that the ex¬
panfion is not equable in the intermediate temperatures:
but we cannot find out a rule which will give, us a more
accurate correction than by taking the expanfion for the
mean temperature.
When we have done this, we have carried the method
of meafuring heights by the barometer as far as it can
go ) and this fource of remaining error makes it needlefs'
to attend to fome other very minute equations which
theory points out. Such is the diminution of the weight
of the mercury by the change of diftance from the centre
of the earth. This accompanies the diminution of the
weight of the air, but neither fo as to compenfate it, nor
to go along with it paripajfu.
After all, there are found cafes where there is a re¬
gular deviation from thofe rules, of which we cannot
give any very fatisfaftory account. Thus it is found,
that in the province of Quito in Peru, which is at a
great elevation above the furface of the ocean, the
heights obtained by thefe rules fall confiderably fhort of
tW
71
P N E U M A T
Barometer, the real heights; and at Spitfbergen they confiderably
u™" exceed them. It appears that the air in the circumpo¬
lar regions is denfer than the air of the temperate cli¬
mates when of the fame heat and under the fame pref-
fure; and the contrary feems to be the cafe with the air
in the torrid zone. It would feem that the fpecific gra¬
vity of air to mercury is at Spitfbergen about I to 10224,
and in Peru about 1 to 13100. This difference is with
great probability afcribed to the greater drynefs of the
circumpolar air.
This fource of error will always remain 5 and it is
combined with another, which fhould be attended to
by all who pradlife this method of meafuring heights,
namely, a difference in the fpecific gravity of the quick-
fdver. It is thought fufficiently pure for a barometer
when it is cleared of all calcinable matter, fo as not to
drag or fully the tube. In this flate it may contain a
confiderable portion of other metals, particularly of fil-
ver, bifmuth, and tin, which will diminifh its fpecific
gravity. It has been obtained by revivification from
cinnabar of the fpecific gravity 14.229, and it is thought
very fine if 13.65. Sir George Shuckburgh found the
quickfilver which agreed precifely with the atmofpheri-
cal obfervations on which the rules are founded, to have
the fpecific gravity 13.61. It is feldom obtained fo
heavy. It is evident that thefe variations will change
the whole refults ; and that it is abfolutely neceffary, in
order to obtain precifion, that we know the denfity of
the mercury employed. The fubtangent of the atmo-
fpherical logarithmic, or the height of the homogeneous
atmofphere, will increafe in the fame proportion with
the denfity of the mercury ; and the elevation correfpond-
ing to one-tenth of an inch of barometric height will
change in the fame proportion.
We muft be contented with the remaining imperfec-
. tions : and we can readily fee, that, for any purpofe
that can be anfwered by fuch meafurements of great
heights, the method is fufficiently exaft 5 but it is quite
inadequate to the purpofe of taking accurate levels, for
directing the conftruftion of canals, aquedufts, and
other works of this kind, where extreme precifion is ab¬
folutely neceflary.
We ffiall now deduce from all that has been faid on
this fubjeft fets of eafy rules for the praftice of this
mode of meafurement, illuftrating them by an example.
1. M. DE Luc's Method.
I c s.
tion by ir±= this produfl, according as the air is above Meaf-idng
or below 3 2°. The produdt is the corredl elevation in , keig.its. ^
fathoms and decimals.
Example.
Suppofe that the mercury in the barometer at the
lower flation was at 29.4 inches, that its temperature
was 50°, and the temperature of the air was 45; and
let the height of the mercury at the upper ftation be
25.19 inches, its temperature 46, and the temperature of
the air 39. Thus we have
$ al Hts. Temp. $ . Mean. Temp. Air. Mean.
48 j* 42
29.4
25<I9
I. Log. of 29.4
Log. of 25.19
46 4
45
3°
1.4683473
1.4012282
Elevation in fathoms
II. Expanf. for 48° .473
Multiply - 4
Approximated elevation
III. Expanf. of air at 42 0.00238
:Io° 10
X 42—32,:
Multiply
By
0.0238
Produff = the correff elevation
671.191
1.892
669.299
669.2990
1.0238
685.228
271
and ac-
2. Sir George ShUCKBURGII's Method.
I. Reduce the barometric heights to what they would cording t0
be if they were of the temperature 3 2°. Shuek-
II. The difference of the logarithms of the reduced burgh,
barometrical heights will give the approximate eleva¬
tion.
III. Correfl the approximated elevation as before.
Same Example.
I. Mean expanf. for i° from Tab. A, is 0.000111.
i8°Xo.oooiii X 29.4= - - 0.059
Subtract this from - - 29.4
Mode of I. Subtract the logarithm of the barometrical height
meafuring upper ftation from the logarithm of that at the
heights by }ower^ ancj count the index and four firft decimal figures
of the remainder as fathoms, the reft as a decimal frac-
cording to tion. Call this the elevation.
De Luc, II. Note the different temperatures of the mercury
at the two ftations, and the mean temperature. Mul¬
tiply the logarithmic expanfion correfponding to this
mean temperature (in Table B, p. 709.) by the differ¬
ence of the two temperatures, and fubtraff the produff
from the elevation if the barometer has been coldeft at
the upper ftation, otherwife add it. Cali the difference
or the fum the approximated elevation.
III. Note the difference of the temperatures of the
air at the two ftations by a detached thermometer, and
alfo the mean temperature and its difference from 3 2°.
Multiply this difference by the expanfion of air for the
mean temperature, and multiply the approximate eleva-
Reduced barometric height - 29.341
Expanf. from Tab. A is 0.000111.
I4°X o.coom X 25.19 - - 0.039
Subtraff from - - 25.190
Reduced barometric height - 25,I5I
II. Log. 29.341 - - 1.4674749
Log. 25.151 - • M°05553
Approximated elevation - 669.196
III. This multiplied by 1.0238 gives 685.125
Remark. 1. If 0.000101 be fuppofed the mean ex- '*7*
panfion of mercury for i°, as Sir George Shuckburgh
determines it, the reduftion of the barometric heights thod ’
will be had fufficiently exaff by multiplying the obfer-
ved heights of the mercury by the difference of its tem¬
peratures
■Barometer, peratures from 32, and cutting oil four more decimal
places; thus 29.4 gives the reduced height
PNEUMATICS.
Corn for temp, of mercurv, =4X 2.83
1132
7! 3
Meafuring
Heights.
*73
*75
10000
J4
*74
Aneafy
rule with¬
out the
help of
tables.
29.347, and 25-I9X~^ gives 25.i55»and tliedlf'
ference of their logarithms gives 669.4 fathoms for the
approximated elevation, which differs from the one gwen
above by no more than 15 inches.
Remark 2. If 0.0024 be taken for the expanfion of
air for one degree, the correftion for this expanfion will
be had by multiplying the approximated elevation by
12, and this product by the fum of the differences of
the’temperatures from 3 2°, counting the difference _ as
negative when the temperature is below 32, and cutting
off four places j thus 669.196 X 12 X !3 “f*°7 X I00c^
16.061, which added to 669,196 gives 685.257, differ¬
ing from the former only 9 inches. .
From the fame premiies we may derive a rule, which
is abundantly exaft for all geodaetical purpofes, and
which requires no tables of any kind, and is eafily re¬
membered. _ .
1. The height through which we muff rife in order to
produce any fall of the mercury in the barometer, is in-
verfely proportional to the denfity of the air, that is, to
the height of the mercury in the barometer.
2. When the barometer Hands at 30 inches, and the
air and quickfilver are of the temperature 3 2, we 1'nui\
rife through 87 feet, in order to produce a depreflion of
Tg- of an inch.
3. But if the air be of a different temperature, this
87 feet muff be increafed or diminifhed by 0.21 of a
foot for every degree of difference of the temperature
from 3 2°. c
4. Every degree of difference of the temperatures of
the mercury at the two ffations makes a change of 2.833
feet, or 2 feet 10 inches in the elevation.
Hence the following rule.
1. Take the difference of the barometric heights m
tenths of an inch. Call this d.
2. Multiply the difference a between 32, and the
mean temperature of the air by 21, and take the fum or
difference of this product and 87 feet. This is the
height through which we muff rife to came the ba¬
rometer to fall from 30 inches to 29.9. Call this
height h.
Let rn be the mean between the two barometric
heights. Thenf°— is the approximated elevation ve-
6 m
iy nearly.
Multiply the difference 2 of the mercurial tempera¬
tures by 2.83 feet, and add this produft to the approxi¬
mated elevation if the upper barometer has been the
warmeft, otherwife fubtraft it. ihe refult, that is, the
fum or difference, will be the corrected elevation.
Same Example.
^—294—251.9=42.1
&=r87+ 10x0.21,= 89.1
.a9.4+WI9=27.29
Approx, elevation
Vol. XVI. Part II.
30x42-1 X 89.1' __
Corrected elevation in feet - 41 II-92'
Ditto in fathoms - - - 685.32
Differing from the former only 15 inches.
This rule may be expreffed by the following fimple
and eafily remembered formula, where a is the diffe¬
rence between 3 2° and the mean temperature of the air,
d is the difference of barometric heights in tenths of an
inch, m is the mean barometric height, £ the difference
between the mercurial temperatures, and E is the cor-
3o(87=±oo.2i<z)i/
276
redl elevation. E:
:^X 2.83.
*77
We fliall now conclude this fubjedt by an account of Heights of
fome of the moft remarkable mountains, &c. on the
earth, above the furface of the ocean, in feet.
remarkable
mountains.
27.29
4123.24 feet.
Mount Puy de Domme in Auvergne, the firfl
mountain meafured by the barometer 5°®^
Mount Blanc ~ - 15662
Monte Piofa -Alps ’ I5°84
Aiguille d’Argenture " - tdd02
Monaflery of St Bernard _ t - - 7944
Mount Cenis - - - 9212
Pic de los Reyes" - - 7620
PicduMedi Pyrenees * ' 93°0
Pic d’Offano ?-r)rcnees . _ II700
Canegou ... §544
Lake of Geneva - - I232
Mount g£tna ... 10954
Mount Vefuvius - - - 393^
Mount Hekla in Iceland - - 4^ 8 7
Snowdown - - - 3555
Ben More - - " 3723
Ben Lawers - - - 3^5^
Ben Gloe - 3472
Schehallion ... 3461
Ben Lomond - - -
Tinto - - - 2342
Table Hill, Cape of Good Hope - 3454
Gondar city in Abyffmia - - 8440
Source of the Nile - - 8082
Pic of Teneriffe - - - 14026
Chimborazo - I9595
Cayambourow - - " I939r
Antifana . . - 19290
Pinchinha ((fee Peru, n° 56.) - - 15670
City of Quito (fee ditto) 9977
Cafpian fea below the ocean - - 306
This laff is fo Angular, that it is neceffary to give the
authority on which this determination is founded. It
is deduced from nine years obfervations with the baro¬
meter at Aftrachan by Mr Lecre, compared with a fe-
ries of obfervations made with the fame barometer at
St Peterfburgh. _
This employment of the barometer has caufed it toimproved
become a very interefting inftrument to the philofopher .arometers,
and to the traveller j and many attempts have beenWlth a Re¬
made of late to improve it, and render it more portable. 0
The improvements have either been diredled to the en¬
largement of its range, or to the more accurate meafure-
ment of its prefent feale. Of the firft kind are Hooke’s
wheel barometer, the diagonal barometer, and the hori¬
zontal barometer, deferibed in a former part of this
4 X work.
f14
Barometer
PNEUMATICS.
Plate
ccccxxx.
Fi^ 73-
270
Itofenor to
tfce com¬
mon one
for the
meafure-
ment of
'Heights.
a So
How the
common
one might
fee impro¬
ved.
■ tvorfc. See Barometer. In that place are alfo defcri-
bed two very ingenious contrivances of Mr Rownings,
which are evidently not portable. Of all the barometers
with an enlarged i’cale the bell is that invented by Dr
Hooke in 1668, and defcribed in the Phil. Tranf. N° 185.
The invention was alfo claimed by Huyghens and by
De la Hire : but Hooke’s was publifhed long before.
It conlifts of a compound tube ABCDEFG (fig. 73.),
of which the parts AB and DE are equally wide, and
EFG as much narrower as we would amplify the feale.
The parts AB and EG muft alfo be as perfectly cy¬
lindrical as poffible. The part HBCDI is filled with
mercury, having a vacuum above in AB. IF is filled
with a light fluid, and EG with another light fluid which
will not mix with that in IF. The ciflern G is of the
fame diameter as AB. It is eafy to fee that the range
of the feparating furface at F muft be as much greater
than that of the furface I as the area of I is greater
than that of F. And this ratio is in our choice. This
barometer is free from all the bad qualities of thofe for¬
merly defoibed, being molt delicately moveable and
is by far the fitteft for a chamber, for amufement, by ob-
fervations on the changes of the atmofpheric preffure.
The flighted: breeze caufes it to rife and fall, and it is
continually in motion.
But this, and all other contrivances of the kind, are
inferior to the common barometer for meafurement of
heights, on account of their bulk and cumberfome-
nefs: nay, they are inferior for all philofophical pur-
pofes in point of accuracy; and this for a reafon that
admits of no reply. Their fcale muft be determined in
all its parts by the common barometer •, and, therefore,
notwithftanding their great range, they are fufceptible
of no greater accuracy than that with which the fcale
of a common barometer can be obferved and meafured.
This will be evident to any perfon who will take the
trouble to cbnfider how the points of their fcale muft
be afeertained. The moft accurate method for gradu¬
ating fuch a barometer as we have now defcribed would
be to make a mixture of vitriolic acid and water, which
fhould have Vo °f the denfity of mercury. Then, let
a long tube ftand vertical in this fluid, and conned its
upper end with the open end of the barometer by a
jfipe which has a branch to which we can apply the
mouth. Then if we fuck through this pipe, the fluid
will rife both in the barometer and in the other tube ;
and 10 inches rife in this tube will correfpond to one
inch defeent in the common barometer. In this manner
may every point of the fcale be adjufted in due propor¬
tion to the reft. But it ftill remains to determins what
particular point of the fcale correfponds to fome deter¬
mined inch of the common barometer. This can only
be done by an adual comparifon-; and this being done,
the whole becomes equally accurate. Except therefore
for the mere purpofe of chamber amufement, in which
cafe the barometer laft defcribed has a decided prefer¬
ence, the common barometer is to be preferred j and
our attention fhould be entirely direded to its improve¬
ment and portability.
For this purpofe it fliould be furnifhed with two mi-
crofcopes or magnifying glaffes, one of them ftationed
at the beginning of the fcale j which Ihould either be
moveable, fo that it may always be brought to the fur¬
face of the mercury in the ciftern, or the ciftern fhould
be fo contrived that its furface may always be brought
to the beginning of the fcale. The glafs will enable us Air i.
to fee the coincidence with accuracy. The other micro- Motion.
fcope muft be moveable, fo as to be fet oppofite to the' V-—1
furface pf the mercury in the tube ; and the fcale fhould
be fumifhed with a vernier which divides an inch into
1000 paits, and be made of materials of which we know
the expanfion with great precifion.
For an account of many ingenious contrivances to aSr
the make inftruments accurate, portable, and commodi¬
ous, confult Magellan, DiJJer.de diverfes Injlr. de Phyf;
Phil. Tranf. Ixvii. Ixviii. Journ. de Phyf. xix. 108. 346.
xvi. 392. xviii. 391. xxi. 436. xxii.390. j Sulzer, Adi.
He/vet. iii. 259. j De Luc, Recherches fur les Modifica¬
tions de /’ Atmofphere, i. 401. ii. 459, 490. De Luc’s
feems the moft Ample and perfed of them all. Cardinal
de Luynes (Mem. Par. 1768) j Prinf. De Luc, £e-
c here lies, § 63.; Van Swinden’s Poftiones Physical;
Com. Acad. Pelrop. i.} Com. Acad. Petrop. Nov. ii.
200 viii.
_ Thus we have given an elementary account of the
diftinguifhing properties of air as a heavy and compref-
fible fluid, and of the general phenomena which are
immediate confequences of thefe properties. This we
have done in a fet of propofitions analogous to thofe
which form the dodrines of hydroftatics. It remains to
confider it in another point of view, namely, as moveable
and inert. The phenomena confequent on thefe proper¬
ties aie exhibited in the velocities which air acquires by
preffure, in the refiftance which bodies meet with to their
motion through the air, and in the impreflion which air
in motion gives to bodies expofed to its adion.
We fliall firft confider the motions of which air is
fufceptible when the equilibrium of preflure (whether
arifing from its weight or its elafticity) is removed; and,
in the next place,. We fliall confider its adion on folid
bodies expofed to its current, and the refiftance which
it makes to their motion through it.
In this confideration we fliall avoid the extreme of ge- Dodhine of
nerality, which renders the difeuflion too abftrad andairinTc*-0
difficult, and adapt our inveftigation to the circum-ceffibie fi¬
nances in which compreffible fluids (of which air istuat!ons as
taken for the reprefentative) are moft commonly found.
We fhall confider air therefore as it is commonly foundparallel
in acceffible fituations, as aded on by equal and parallel gravity,
gravity ; and we ffiall confider it in the fame order in
which water is treated in a fyftem of hydraulics. 2S
In that fcience the leading problem is to determine analogous
with what velocity the water will move through a given to the
orifice when impelled by fome known preffure; and itdodrineof
has been found, that the bell form in which this moft
difficult and intricate propofition can be put, is to de- ^ rau ie-'
termine the velocity of water flowing through this ori¬
fice when impelled by its weight alone. Having de¬
termined this, we can reduce to this cafe every queftion
which can be propofed ; for, in place of the preffure
of any pifton or other mover, we can always fubftitute
a perpendicular column of water or air whofe weight
fhali be equal to the given preffure.
The firft problem, therefore, is to determine with The velo-
what velocity air will rulh into a void when impelled city with
by its weight alone. This is evidently analogous to thewhich.air
hydraulic problem of water flowing out of a veffel. rulhesinte
And here we muft be contented with referring ourf^wn 7
readers to the folutions which have been given of that weight,
problem,
P N E U M
Air in problem, and the demonftration that it flows with the
Motion, velocity which a heavy body would acquire by falling
""’"‘v from a height equal to the depth of the hole under the
furface of the water in the veffel. In whatever way we
attempt to demonftrate that propofltion, every itep, nay,
every word, of the demonftration applies equally to the
air, or to any fluid whatever. Or, if our readers fttould
wifti to fee the conne&ion or analogy of the cafes, we
only defire them to recoiled! air undoubted maxim m
the fcience of motion, that when the moving force and
the matter to be moved vary in the fame proportion, the
velocity will be the fame. If therefore there be finular
veffels of air, water, oil, or any other fluid, all of the
height of a homogeneous atmofphere, they will all run
through equal and fimilar holes with the lame velocity j
for in whatever proportion the quantity of matter mo¬
ving through the hole be varied by a variation ox denfity,
the preflure which forces it out, by afting in circum-
ftances perfedlly fimilar, vanes in the fame proper Lion
by the fame variation of daofity.
We muft therefore a flume it as the leading propofi-
tion, thattf/r ru floes from the atmofphere into^ a void with
the velocity which a heavy body would acquire by failing
from the top of a homogeneous atmofphere.
It is known that air is about 840 times lighter than
water, and that the preflure of the atmofphere fupports
water at the height of 33 feet nearly. The height there¬
fore of a homogeneous atmofphere is nearly 33 ^
or 'iqq'io feet. Moreover, to know tne velocity ac¬
quired by any fall, recoiled! that a heavy body by fail¬
ing one foot acquires the velocity of 8 feet per fecond }
and that the velocities acquired by falling through
different heights are as the fquare roots of the heights.
Therefore to find the velocity correlpondmg to any
height, expreflied in feet per lecond, multiply the fquaie
root of the height by ^ We have therefore in the
prefent inftance 27220, 1=8 X Ib6.493»> —1332,
feet per fecond. This therefore is th# velocity with
which common air will rufti into a void } and this may
be taken as a ftandard number in pneumatics, as 16 and
3 2 are ftandard numbers in the general fcience of me¬
chanics, exprefling the adlion of gravity at the furface
of the earth.
It is eafy to fee that greater precifion is not neceflary
in this matter. The height of a homogeneous atmo-
iphere is a variable thing, depending on the temperature
of the air. If this reafon feems any objedlion again!!
the ufe of the number 1332, we may retain in
place of it, where H exprefles the height of a homoge¬
neous atmofphere of the given temperature. A varia¬
tion of the barometer makes no change in the velocity,
nor in the height of the homogeneous atmofphere, be-
caufe it is accompanied by a proportional variation in
the denfity of the air. When it is increafed do-> for in-
ftance, the denfiLy is alfo increafed \ and thus the
expelling force and the matter to be moved are changed
in the fame proportion, and the velocity remains the
fame. N. B. We do not here confider the velocity
which the air acquires after its ifluing into the void by
its continual expanfion. This may be afeertained by
the 39th prop, of Newton’s Principia, b. i. Nay, which
appears very paradoxical, if a cylinder of air, communi¬
cating in this manner with a void, be comprefled by a
pifton loaded with a weight, which prefles it down as
the air flows out, and thus keeps it of the fame denfity,
7r5
Air in
Motion.
A T I <5 S.
the velocity of efflux will ftill be the fame, however great
the preilure may chance to be : for the firl! and imme- ^
diate effect of the load on the pifton is to reduce the air
in the cylinder to fuch a denfity that its elafticity ftiall
exadtly balance tbe load } and becauie the elafticity of
air is proportional to its denfity, the denfity 01 the air
will be increafed in the fame proportion with the load,
that is, with the expelling power (for we are negledling
at prefent the weight of the included air as too inconfi-
derable to have any fenfible effedf). Therefore, fince the
matter to be moved is increafed in tbe fame proportion
with the preflure, the velocity will be tbe fame as be-
fore. _ _ . 2S5
It is equally eafy to determine the velocity with which and the
the air of the atmofphere will ru!h into a fpace contam,velocity
ing rarer air. Whatever may be the denftty of this air,.'^^IC 1
its elafticity, which follows {he proportion of its denfity, int0 a fpace
will balance a proportional part of the preflure of the containing
atmofphere ; and it is the excefs of this laft only which rarer air,
is the moving force. The matter to be moved is the
fame as before. Let D be the natural denfity of the
air, and £ the denfity of the air contained in the veflel
into which it is fuppofed to run, and let P be the
preffure of the atmofphere, and therefore equal to the
force which impels it into a void ^ and let w be the
force with which this rarer air would run into a void.
We have D : orrP : tt, and w——
force in the prefent inftance is P—w, or P
Now the moving
PJ
D *
Laftly, let V be the velocity of air ruffling into a void,
and v the velocity with which it will ru!h infto this
rarefied air.
It is a theorem in the motion of fluids, that the
prefiures are as the fquares of the velocities of efflux.
P i
Therefore P : P—— =VS : vl. Hence we derive
V7~
—V2 X 1—and ^ X V:
D
We do not
here confider the refiftance which the air of the atmo¬
fphere will meet with from the inertia of that in the
veflel which it muft difplace in its motion.
Here we fee that there will always be a current into
the veflel while 5 is lefs than D.
We alfo learn the gradual diminution of the velocity
as the veflel fills} for ^ continually increafes, and there¬
fore
D
continually diminifhes.
It remains to determine the time / expreffed in fe-
conds, in which the air of the atmofphere will flow into
this veflel from its Hate of vacuity till the air in the vef¬
fel has acquired any propofed denfity
For this purpofe let H, exprefled in feet, be the
height through which a heavy body muft fall in order
to acquire the velocity V, exprefled alfo in feet per fe¬
cond. This we fliall exprefs more briefly in future, by
calling it tbe height producing tbe velocity V. Let
C reprefent the capacity of the veflel, exprefled in cubic
feet, and O tbe area or fe&ion of the orifice, exprefled
in fuperficial or fquare feet j and let the natural denfity
of the air be D.
Since the quantity of aerial matter contained in a
veflel depends on the capacity of the veflel and the
denfity of the air jointly, we may exprefs the air which
4X2 would
P N E U M
would fill this veil'd bv the Ivinbol CD when the air
js in its ordinary hate, and by C 3 when it has the
denlity In order to obtain the rate at which it fills,
we mufl take the fluxion of this quantity C This
is C ^ j for C is a conifant quantity, and I is a variable
or flowing quantity.
But we alfo obtain the rate of influx by our know¬
ledge of the velocity, and the area of the orifice, and
the denfity. The velocity is V, or 8 y'H, at the firfl
in ft ant; and when the air in the velfel has acquired the
denfity that is, at the end of the time /, the velocity
is 1—~, or SyTi
y
D—o
D ’
v/D
or 8 v'H
The rate of influx therefore (which may be con¬
ceived as meafured by the little mafs of air which will
enter during the time t with this velocity) will be
S^/HOD-v/dHS / „   
> or Sy'HO-v/D^/D—3 /, multi¬
plying the velocity by the orifice and the denfity.
Here then we have two values of the rate of influx.
By ftating them as equal we have a fluxionary equation,
from which we may obtain the fluents, that is, the
time t in feconds neceffary for bringing the air in the
veffel to the denfity or the denfity £ which will be
produced at the end of any time /. We have the equa¬
tion 8 -v/HOvfD v/D—Hence we derive
C j
t—- ^:X—7- Of this the fluent is
’ 8 ydfO ykD
C
\/D—
2$6
Ihuftrated
by ex¬
amples in
numbers.
/~4VHOvrDX ^A is a con¬
ditional conllant quantity. The condition which de¬
termines it is, that t muff be nothing when o is nothing,
that is, when \/D—Jzr'v/D’; for this is evidently
the cafe at the beginning of the motion. Hence it
follows, that the conftant quantity is V D, and the
complete fluent, fuited to the cafe, is
qi/iioTl)x ^ D~~ v/D~J
I he motion ceafes when the air in the vefiel has ac¬
quired the denfity of the external air ; that is, when
C r
D, or when /~  v ./D —- -
4\/HOy/D X x/L>’ 77hO’
Therefore the time of completely filling the veffel is
WHO-
Let us illuftrate this by an example in numbers.
Suppofing then that air is 840 times lighter than wa¬
ter, and the height of the homogeneous atmofphere
2*7720 feet, we have 4v/H—666. Bet us further fup-
pofe the veffel to contain 8 cubic feet, which is nearly
a wine hogfhead, and that the hole by which the air of
the ordinary denfity, which we fhall make =r, enters
is an inch fquare, or of a fquare foot. Then the
O;
time in feconds of completely filling it will be
t^666’
11 <; 2"
or 1.7297"
666
If the hole is only of
fquare inch3 that is? if its fide is of an inch3 the time
very
A T I C S.
of completely filling the hogfhead will be 173''
nearly, or fomething lets than three minutes.
If we make the experiment with a hole cut in a thin
plate, we fhall find the time greater nearly in the pro¬
portion of 63 to 100, for reafons obvious to all who
have ftudied hydraulics. In like manner we can tell the
time neceffary for bringing the air in the veffel to 4- of
its ordinary denfity. The only variable part of our
fluent is the coefficient —^/D—or Let £
be —then ^/i — and 1—^ 1—§ —
and the time is 861" very nearly when the hole is T'o of
an inch wide.
Let us now fuppofe that the air in the veffel ABCD Fis?. Sr.
(fig. 81.) is compreffed by a weight afling on the cover 287
AD, which is moveable down the veffel, and is thusTheve!o~
expelled into the external air.
The ^immediate effecft of this external preffure is tordditional
compreis the air and give it another denfity. The impulfe °f
denfily D of the external air correfponds to its preffure a wf’ght
P. Let the additional preffure on the cover of the ?°Vinfh
veffel be />, and the denfity of the air in the veffel veffeL
be d. We fhall have P : P-j-/;—D : d; and therefore
^ • Then, becaufe the preffure which ex¬
pels the air is the difference between the force which
compreffes the air in the veffel and the force which
compreffes the external air, the expelling force is
/>. And becaufe the quantities of motion are as the
forces which fimilarly produce them, we fhall have
^ ^ X ”D ~ MV : m v; where M and jn exprefs
Urn quantities of matter expelled, V expreffes the ve¬
locity with which air rufhes into a void, and v ex-
prefies the velocity fought. But becaufe the quanti¬
ties of aerial matter which iffue from the fame orifice in
a moment are as the denfities and velocities jointly,
we fhall have MV : ra z>rrDVV ; dvv, — DV1 :
Therefore P : DVa : dv. Hence we deduce
=vy:
d—D)
d \
We may have another expreffion of the velocity with¬
out confidering the denfity. We had P : P-j-/i—D ; d:
therefore dz
DXP+/.
p ?
D=^2<_P±^_
P
I>,
__ I) x P ArP—DP , d—D _ D X P-f/>—DP
P+Z—P _
?+/>
d
therefore
v=n x y.
L> XP-f^
P
P+P
, which
confidered.
81.
P ~\-P
is a very fimple and convenient expreffion.
Hitherto we have confidered the motion of air as pro-The cffeft
duced by its weight only. Let us now confider the ef- ot the air’s
fe£l of its elafticity. elafticity
Let ABCD (fig. 81.) be a veffel containing air ofc7^U
any denfity D. This air is in a flate of compreffion ; FlS’
and if the compreffing force be removed, it will expand
and its elafticity will diminifh along with its denfity.
Its elafticity in any ftate is meafured by the force which
keeps it in that ftate. The force which keeps common
air in its ordinary denfity is the weight of the atmo¬
fphere, and is the fame with the weight of a column of
water 33 feet high. If therefore we fuppofe that this
P N E U M
air, inffcad of being confined by tbe top of the veflel, is
preffed down by a moveable pifton carrying a column ol
' water feet high, its elafticity will balance this prel-
fore as it balances the preffure of the atmoiphere j and
as it is a fluid, and propagates through every part the
preffure exerted on any one part, it wiH prefs on any
little portion of the veffel by its elafticity m the fame
manner as when loaded with this column. .. , .
The confequence of this reafoning is, that n this
fmall portion of the veffel be removed, and thus a pat-
fage be made into a void, the air will begin to flow out
with the fame velocity with which it would flow when
impelled by its weight alone, or with the velocity ac¬
quired by falling from the top of a homogeneous atmo¬
iphere, or 1332 feet in a fecond nearly. r
But as foon as fome air has come out, the denfity of
the remaining air is diminiflied, and its elafticity is di-
minilhed ; therefore the expelling force is dimmiflied.
But the matter to be moved is dimimlhed m the very
fame proportion, becaufe the denfity and elafticity are
found to vary according to the fame law ; therefore the
velocity will continue the fame from the beginning to.
the end of the efflux. r •. r>- u
This may be feen in another way. Let F be the
preffure of the atmofphere, which being the counter¬
balance and meafure of the initial elafticity, is equal to
the expelling force at the firft inftant; Let D be the
initial denfity, and V the initial velocity. Let </ be its-
tlenfity at the end of the time / of efflux, and v the
contemporaneous velocity. It is plain that at the end
of this time we fflall have the expelling force
YA
A T I C S.
. _c/
—Cr/, and /:
:8 v'HCV’
The fluent of this is t~-
C d
:87ho x ~ 7f
C I°g. d. I his fluent
8\/HO
muft be fo taken that t may be=o wheW=D. There¬
fore the corredh fluent will be t ~ g x°l
^ ^_l0ga —0. We deduce from this, that it
requires an infinite time for the whole air of a veffel to
flow, out of it into a void. N. B. By log. d, &c. is
meant the hyperbolic logarithm of d, &.c. . apo
Let us next fuppofe that the veffel, mftead of letting, when the-
out its air into a void, emits it into air of a lefs den-veffe^errn^
fity, which remains conftant during the efflux, as we^orar
may fuppofe to be the cafe when a veffel containing
condenfed air emits it into the furrounding atmo¬
fphere. Let the initial denfity of tlm air m the venel
be 5, and that of the atmofphere D. Then it is plain
that the expelling force is P y, and that after
the time t it is  y We have therefore P y
/ P^\
for D : d=Y : J
289
Quantity
of air 1 fin¬
ing into a
void in a
given time
and the
denfity at
EA — —=MV:mv, =dV*:dv\
5 3
Whence we
y
$ d—D
Thefe forces are proportional to the quantities of mo¬
tion which they produce j and the quantities of motion
are proportional to the quantities of matter M and m
and the velocities V and ^ jointly : therefore we have
p . _ MV ; m v. But the quantities of matter
x ■ j)
which efcape through a given orifice are as the denfities
and velocities jointly, that is, M : m=T>V : dv : theie-
fore p ; Lf—DV*: dv\ and ?xdv'=-y—= ?dV ,
and V*—t;1, and V=v, and the velocity of efflux is
conftant. Hence follows, what appears very unlikely
at firft fight, that however much the air m the yellel is
condenfed, it will always iffue into a void with the lame
V~In o"rder to find the quantity of aerial matter which
will iffue during any time t, and confequently the den¬
fity of the remaining air at the end of this time, we
muft get the rate of efflux. In the element of time
/ there iffues (by what has been faid above) the bulk
8v/HO/ (for the velocity Vis conftant) j and there-
“IVo'f fore the quantity 8 VHOy On the other hand, the
that time, quantity of air at the beginning w^as LD, L being t .e
capacity of the veffel j and when the air has acquired
the denfity d, the quantity is C d, and the quantity
run out is CD—C d: therefore the quantity which has
run out in the time t muft be the fluxion of CD C d,
or—C</. Therefore we have the equation %s/U0dt =.
derive v — V __
d ^—D
From this equation we learn that the motion will be
at an end when d-Y> : and if $=D there can be no
efflux. . j -u j 2QI
To find the relation between the time and the den- Relation ^
fity, let H as before be the height producing the velo- between
city V. The height producing the veloc.ty of
S d—D , , i r • when iifu-
g; muft be H x -=> and the llttle Parcel of air ing into a
d'b—D . void,
which will flow out in the time t will be
J.
d—D
d$^D\
On the other hand, it is = — C d.
Hence we deduce the fluxionary equation /
Cjf-
D
The fluent of this, correff-
Cv^—D
VH°v/5Xs/^—
ed fo as to make t—Q wThen d=^, is i— g
v W And the time of com-
X \d—jD-j-^yd1—D</' 
, ^ . cy^ —Dv ,
pleting the efflux, when a—D, is/—0^"
V iD r
Laftly, kt ABCD, CFGH (fig. 82.) be two veffels 82*
containing airs of different denfities, and communicating \yhe, jiru-
by the orifice C, there will be a current from the veffel ing from
containing the denfer air into that containing the rarer : dc“< ^ .nto
fuppofe from ABCD into CFGH. _ _ ^ raierair'
Let P be the elaftic force of the air in ABCD,
its denfity, and V its velocity, and D the denfity of the
air in CFGH. And, after the time /, let the denfity
of the air in ABCJD be q, its velocity v, and the denfi-
ty of the air in CFG H lie The expelling force from
ABCD will be P at the firfl inflant, and at the
end of the time i it will be ~q — — • Therefore we
n , PD P q P'^ ‘V_
Hi all have F — : -q   — OF.1 : g v2, which
gives v—\ x s/—-fry, and the motion will ceafe
when o—y.
c A be the capacity of the firft veflel, and B that
Oi the fecond. We have the fecond equation AO
_ A (Q—y) -f- BD
PNEUMATICS.
BD—Ay-J-B5, and therefore
oubPituting this value of £ in the former value of v
B
, which
wc have v= x /g.[*H?-D)--A(Q-?)]
. . , . ?B(Q_D)
gives the relation between the velocity v and the den-
% 7-
In order to afcertain the time when the air in
ABCD has acquired the dcnfityy, it will be convenient
to abridge the work by fome fubftitutiens. There¬
fore make £) (B-f A)=M, B(^D-fB^2=N, BO—
BD—R and — Then, proceeding as before, we
obtain the fluxionary equation jl^HOy^—bf
-N.
\/B V9
Av/R
is t —
293 ,
When air
AO—Ay — — Ay, whence x ——•
y 8 v'HOy'M ^mq
of which the fluent, completed fo that t~o when y—Q,
At/R ^Q—\/(Qz^Q)\
8 v/HOv/MX 0 v y—^{jf m q) /
is ex elled Some of thefc queftions are of difficult folution, and
by force, as are no^ frequent ufe in the more important and
in bellows, ufoal. applications of the doftrines of pneumatics, at
leal! in their prefent form. The cafes of greateft ufe are
when the air is expelled from a veflel by an external
force, as wRen bellows are worked, whether of the or¬
dinary form or confiftmg of a cylinder fitted -with a move-
able pifton. This laft cafe merits a particular confide-
ration; and, fortunately, the inveftigation is extremely
eafy.
Fig. Si. Let AD fig. 81. be confidered as a pifton movino-
downward with the uniform velocity f and let the area
of the pifton be n times the area of the hole of efflux,
then the velocity of efflux arifing from the motion of
tne pifton will be Add this to the velocity V pro¬
duced by the elafhcity of the air in the firfl: queffion,
and the whole velocity will be VIt will be the
fame in the other. The problem is alfo freed from the
confideration of the time of efflux. For this depends
now on the velocity of the pifton. It is ftill, however,
a very intricate problem to afcertain the relation bet'ween
the time and the denfity, even though the pifton is mov¬
ing uniformly j for at the beginning of the motion the
air is of common denfity. As the pifton defcends, it
both expels and compreffes the air, and the denfity of
the air in the veflel varies in a very intricate manner, as
alfia its refiftance or reaclion on the pifton. For this
.rea (on, a pifton which moves uniformly by means of an
Air [»
Motion.
external force will never make an uniform blatl by fuc-
cefllve ftrokes; it will always be weaker at the begin¬
ning of the ftroke. I he beft way for focuring an uni¬
form blaft is to employ the external force only for lift¬
ing up the pifton, and then to let the pifton defcend by
its own weight. In this way it will quickly fink down,
comprefting the air, till its denfity and correfponding
elallicity exaifly balance the weight of the piflon. Af¬
ter this the pifton will defcend equably, and the blaft:
will be uniform. We fflalh have occaflon to confider
this more particularly under the head of Pneumatical
Machines. Thefe obfervations and theorems will ferve
to determine the initial velocity of the air in all im¬
portant cafes of its expulfion. The philofopher will learn
the rate of its efflux out of one veflel into another; the
chemift will be able to calculate the quantities of the
different gafes which are employed in the curious expe¬
riments of the ingenious but unfortunate Lavoifler on
Combuftion, and will find them extremely different from
what he fuppofed 5 the engineer will learn how to pro¬
portion the motive force of his machine to the quantity
of aerial matter which his bellows muft fupply. But
it is not enough, for this purpofe, that the air begin
to iffue in the proper quantity; we muft foe whether it
be not affetfted by the circumftances of its fubfoquent
pafiage.
All the modifications of motion which are obforved Paflage of
in water conduits take place alfo in the paffage of air air through
through pipes and holes of all kinds. There is the P;Pes’ &c-
fame diminution of quantity palling through a hole infimilar to
a thin plate that is obferved in water. We knowofwTSfo
that (abating the fmall effetft of fricTion) Water if-conduits
fues with the velocity acquired by falling from the
furfacej and yet if we calculate by this velocity and
by the area of the orifice, we lhall find the quantity
of water deficient nearly in the proportion of 63 to 100.
f his is owing to the water preffing towards the orifice
from all ftdes, which occafions a contra£lion of the jet.
The fame thing happens in the efflux of air. Alfo the
motion of water is greatly impeded by all contradions
of its paffage. Thefe oblige it to accelerate its veloci¬
ty, and therefore require an increafe of preffure to force
it through them, and this in proportion to the fquares
the velocities. Thus, if a machine working a pump
cauies it to give a certain number of ftrokes in a mi¬
nute, it will deliver a determined quantity of water in
that time. Should it happen that the paffage of the
water is contradled to one half in any part of the ma¬
chine (a thing which frequently happens at the valves),
the water muft move through this contraflion with twice
the velocity that it has in the reft of the paffage. This
will require four times the force to be exerted on the
pifton. Nay (which will appear very odd, and is ne¬
ver fufpefted by engineers), if no part of the paffage .is
narrower than the barrel of the pump, but on the con¬
trary a part much wider, and if the conduit be again
contradled to the width of the barrel, an additional force
muft be applied to the pifton to drive the water through
this paffage, which would not have been neceffary if the
pafiage had not been widened in any part. It will re¬
quire a force equal to the weight of a column of water
ot the height neceffary for communicating a velocity, the
fquare of which is equal to the difference of the fquares
of the velocities of the water in the wide and the nar¬
row part of the conduit.
The
PNEUMATICS.
7*9
295
Air fulTers
the fame
retardation
along pipes
as water,
and the
neceffity of
attending
to this.
The fame thing takes place in the motion of air, and
therefore all contractions and dilatations muft be. care-
fally avoided, when we want to preferve the velocity un¬
impaired. ...
Air alfo fujfers the fame retardation in .its motion
along pipes. By not knowing, or not attending to t.iat,
engineers of the firft reputation have been prodigioufl.y
difappointed in their expectations of the quantity of air
which will be delivered by long pipes. Its extreme
mobility and lightnefs hindered them from fufpeCting
that it would fuffer any fenfible retardation. Dr Pa¬
pin, a moft ingenious man, propofed this as the molt
effectual method of transferring the. aCtion of a moving
power to a great diftance. Suppofe, for inftance, that
it was required to raife water out of a mine by a wa¬
ter-machine, and that there was no fail of water neai er
than a mile’s diftance. He employed this water to
drive a pifton, which ftiould comprefs the air in a cy¬
linder communicating, by a long pipe, with another
cylinder at the mouth of the mine. This fecond cy¬
linder had a pifton in it, whofe rod was to give motion
to the pumps at the mine. He expefted, that as foon
as the pifton at the water-machine had compreffed the
air Sufficiently, it would caufe the air in the cylinder
at the mine to force up its pifton, and thus work the
pumps. Dr Hraoke made many objections to the
method, when laid before the Royal Society, and it
was much debated there. But dynamics was at this
time an infant fcience, and very little underftood. New¬
ton had not then taken any part in the bufinefs of the
fociety, otherwife the true objections would not have
efcaped his fagacious mind. Notwithftanding Papin’s
great reputation as an engineer and mechanic, he could
not bring his fcheme into ufe in England ; but after¬
wards, in France and in Germany, where he fettled, he
got fome perfons of great fortunes to employ him in this
projeCt ; and he ereCted great machines in Auvergne
and Weftphalia for draining mines. But, fo far from
being effective machines, they would not even, begin to
move. He attributed tbe failure to the quantity of air
in the pipe of communication, which muft be condenfed
before it can condenfe the air in the remote cylinder.
This indeed is true, and he fhould have thought of this
earlier. He therefore diminiflied the fize of this pipe,
and made his water-machine exhauft inftead of conden-
fmg, and had no doubt but that the immenfe velocity
with which air nifties into a void would make a rapid
and effeChial communication of power. But he was
equally difappointed here, and the machine at the mine
flood ftill as before.
Near a century after this, a very intelligent engineer
attempted a much more feafible thing of this kind at an
iron-fouqdery in Wales. He ereCIed a machine at a
powerful fall of water, which worked a fet of cylinder
bellows, the blowpipe of which was conduCled to the
diftance of a mile and a half, where it was applied to a
blaft furnace. But notwithftanding every care to make
the conducting pipe very air-tight, of great fize, and as
fmooth as poftible, it would hardly blow out a candle.
The failure was afcribed to the impoftibility of making
the pipe air-tight. But, what was furprifing, above ten
minutes elapfed after tbe aftion of the piftons in the hel¬
lo ws before the leaft wind could be perceived at the end
of.the pipe; whereas the engineer expeCted an interval
of 6 feconds only.
No very diftinCI theory can be delivered on this fub-
leCl; but we may derive confiderable affiftance in un-
derftanding tbe caufes of the obftruCtion to the motion
of water in long pipes, by confidering what happens
to air. The elafticity of the air, and its great com-
preffibility, have given us the diftinCleft notions of flui¬
dity in general, fhowing us, in a way that can hardly
be controverted, that the particles of a fluid are kept
at a diftance from each other, and from other bodies,
by the corpufcular forces. We {hall therefore take this
opportunity to give a view of the fubjeCt, which did not
occur to us when treating of the motion of water in pipes,
referving a further difcuflion to the articles River, JVa-
TE E-Works.
The writers on hydrodynamics have always confider-
ed the obftruClion to the motion of fluids along canals
of any kind, as owing to fomething like the friCtion by
which the motion of folid bodies on each other is ob-
ftrufted ; but we cannot form to ourfelves any diftinCt
notion of refemblanCe, or even analogy between them.
The faCl is, however, that a fluid running along a ca¬
nal has its motion obftrucled ; and that this obftruc-
tion is greateft in the immediate vicinity of the folid
canal, and gradually dmiiniflies to the middle of the
ftream. It appears, therefore, that the parts of fluids
can no more move among each other than among fo¬
lid bodies, without fuffering a diminution of their mo¬
tion. The parts in phyflcal ccntaCft with the fldes and
bottom are retarded by thefe immoveable bodies. The
particles of the next ftratum of fluid cannot preferve
their initial velocities without overpafling the particles
of the firft ftratum ; and it appears from the fa£l that
they are by this means retarded. They retard in the
fame manner the particles of the third ftratum, and fo
on to the middle ftratum or thread of fluid. It ap¬
pears from the faft, therefore, that this fort of fri&ion
is not a confequence of rigidity alone, but that it is
equally competent to fluids. Nay, fince it is a matter
of facf in air, and is even more remarkable there than
in any other fluid, as we fhall fee by the experiments
which have been made on the fubjedl; and as our ex¬
periments on the compreflion of air fliow us the par¬
ticles of air ten times nearer to each other in fome cafes
than in others (viz. when we fee air a thoufand times
denfer in thefe cafes), and therefore force us to ac¬
knowledge that they are not in contafl; it is plain that
this obftru&ion has no analogy to friction, which fup-
pofes roughnefs or inequality of furface. No fuch ine¬
quality can be fuppofed in the furface of an aerial par¬
ticle ; nor would it be of any fervice in explaining the
obftruftion, fince the particles do not rub on each other,
but pafs each other at fome fmall and imperceptible dif¬
tance.
We muft therefore have recourfe to fome other mode
of explication. We fhall apply this to air only in this
place ; and, fince it is proved by the incontrovertible
experiments of Canton, Zimmerman, and others, that
water, mercury, oil, &c. are alfo compreflible and per-
feftly elaftic, the argument from this principle, which
is conclufive in air, muft equally explain the fimilar
phenomenon in hydraulics.
The moft highly polilhed body which we know muft
be conceived as having an uneven furface ifhen we
compare it with the fmall fpaces in which the corpuf
cular forces are exerted ; and a quantity of air moving
Air in
Motion.
25)5.
No diltir.ift;
theory on
this fubjedl.
How fluids
are ob-
ftrudted in
moving
along ca¬
nals.
m r:
yia
PNEUMATIC Si
2P7
change
from a rec¬
tilineal to
an undula¬
ting mo-
won,
in a polillied pipe may be compared to a quantity of
fmall fhot Hiding down a channel with undulated lides
and bottom. The row of particles immediately conti¬
guous to the lides will therefore have an undulated mo¬
tion : but this undulation of the contiguous particles
of air will not be lo great as that of the furface
along which they glide 5 for not only every motion
requires force to produce it, but alfo every change of
Particles of motion. The particles of air refill; this change from
air refill a a reftilJneal t0 an undulating motion ; and, being ela-
ftic, that is, repelling each other and other bodies,
they keep a little nearer to the furface as they are paf-
fing over an eminence, and their path is lels incurvated
than the furface. The difference between the motion of
the particles of air and the particles of a fluid quite un-
elaftic is, in this refpeft, fomewhat like the difference be¬
tween the motion of a fpring-carriage and that of a com¬
mon carriage. When the common carriage paffes along
a road not perfeflly fmooth, the line defcribed by the
centre of gravity of the carriage keeps perfedlly pa¬
rallel to that defcribed by the axis of the wheels, ri¬
ling and falling along with it. Now let a fpring body
be put on the fame wheels and pafs along the fame road.
When the axis rifes over an eminence perhaps half an
inch, finks down again into the next hollow, and then
fifes a fecond time, and fo on, the centre of gravity of
the body defcribes a much ftraighter line } for upon the
riling of the wheels, the body refills the motion, and
compreiTes the fprings, and thus remains lower than it
would have been had the fpnngs not been interpofed.
In like manner, it does not fink fo low as the axle does
when the wheels go into a hollorv. And thus the mo¬
tion of fpring-carriages becomes lefs violently undulated
than the road along which they pafs. This illuffration
will, we hope, enable the reader to conceive how the
deviation of the particles next to the fides and bottom
of the canal from a reflilineal motion is lefs than that of
the canal itfelf.
It is evident that the fame reafsning will prove that
the undulation of the next row of particles will be lefs
than that of the firlt, that the undulation of the third
row will be lefs than that of the fecond, and fo on, as
will be lefs is reprefented in fig. 83. And thus it appears, that
than that while the mafs of air has a progreflive motion along the
pipe or canal, each particle is defcribing a waving line,
of which a line parallel to the direction of the canal is
the axis, cutting all thefe undulations. This axis of
each undulated path will be ftraight or curved as the ca¬
nal is, and the excurfions of the path on each fide of its
axis will be lefs and lefs as the axis of the path is nearer
to the axis of the canal.
Let us now fee what fenjtble effect this will have ; for
all the motion which we here fpeak of is imperceptible.
It is demonftrated in mechanics, that if a body moving
with any velocity be deflefred from its redlilineal path
by a curved and perfectly fmooth channel, to which the
rectilineal path is a tangent, it will proceed along this
channel with undiminiflied velocity. Now the path, in
the prefent cafe, may be confidered as perfectly fmooth,
fince the particles do not touch it. It is one of the un¬
dulations which we are confidering, and we may at pre¬
fent conceive this as without any fubordinate inequali¬
ties. There fliould not, therefore, be any diminution
of the velocity. Let us grant this of the abfolute ve¬
locity of the particle} but what we obferve is the ve¬
4
298
and the
undulation
of the fe¬
cond row
of particles
of the firft.
S3.
299
Each par¬
ticle ap¬
pears to
lofe no ve¬
locity.
locity of the mafs, and we judge of it perhaps by the Air in
motion of a feather carried along by it. Let us fup-, Motion,
pofe a Angle atom to be a fenfible objeft, and let us at-
tend to two fuch particles, one at the fide, and the other
in the middle: although we cannot perceive the undu¬
lations of thefe particles during their progreffive mo¬
tions, we fee the progreflive motions themfelves. Let
us fuppofe then that the middle particle has moved
without any undulation whatever, and that it has ad¬
vanced ten feet. The lateral particle will alfo have
moved ten feet •, but this has not been in a ftraight line.
It will not be fo far advanced, therefore, in the direc¬
tion of the canal j it will be left behind, and will ap¬
pear to us to have been retarded in its motion : and in
like manner each thread of particles will be more and
more retarded (apparently only) as it recedes farther
from the axis of the canal, or what is ufually called the
thread of the ftream.
And thus the obferved faft is fhown to be a necef- Sutton the
fary confequence of what we know to be the nature of whole the
a compreflible or elaftic fluid •, and that without fup- undulatory
pofing any diminution in the real velocity of each par- motlon is a
tide, there will be a diminution of the velocity of the ^uufhcn
fenlible threads of the general ftream, and a diminution
of the whole quantity of air which paffes along it during
a given time.
Let us now fuppofe a parcel of air impelled along
a pipe, which is pcrfeBhj fmooth, out of a larger
veflel, and iffuing from this pipe with a certain velocity.
It requires a certain force to change its velocity in the
veffel to the greater velocity which it has in the pipe.
This" is abundantly demonftrated. How long foever
we fup^ofe this pipe, there will be no change in the ve¬
locity, or in the force to keep it up. But let us fup-
pofe that about the middle of this pipe there is a part of
it which has fuddenly got an undulated furface, how¬
ever imperceptible. Let us further fuppofe that the
final velocity of the middle thread is the fame as be¬
fore. In this cafe it is evident that the fum total of the
motions of all the particles is greater than before, be-
caufe the abfolute motions of the lateral particles is
greater than that of the central particle, which we fup¬
pofe the fame as before. This abfolute increafe of mo¬
tion cannot be without an increafe of propelling force :
the force a&ing now, therefore, muft be greater than
the force adding formerly. Therefore, if only the for¬
mer force had continued to a£l, the fame motion of
the central particle could not have been preferved, or
the progreftive motion of the whole ftream muft be di-
minifhed.
And thus we fee that this internal infenfible undula-
tory motion becomes a real obftrudlion to the fenfible
motion which we obferve, and occafions an expence of
power. _ 30I
Let us fee what will be the confequence of extend- An addl¬
ing this obftrudling furface further along the canal, tional force
It muft evidently be accompanied by an augmentation nectff ry
of the motion produced, if the central Velocity be ftill^ r Pre^e.r"
kept up 5 for the particles which are now in con tad! venb::roT
with the fides do not continue to occupy that fituation ; greffive mo»
the middle particles moving fafter forward get overft0n>
them, and in their turn come next the fide ; and as
they are really moving equally faft, but not in the di¬
re dlion into which they are now to be forced, force is
neceffary for changing the diredtion alfo 3 and this is in
addition
3°*
efpecially
through
any con-
tradlioii.
303
There are
befides
other ob-
ftrudlions,
&c.
P N E U M
addition to the force neceflavy for producing the undula¬
tions fo minutely treated of. The confequence of this
mull be, that an additional force will be neceifary for
preferving a given progrefiive motion in a longer ob-
Jlruciing pipe, and that the motion produced in a pipe of
greater length by a given force will be lefs than in a
fhorter one, and the efflux will be diminifhed.
There is another confideration which muft have a*a
influence here. Nothing is more irrefragably demon-
ftrated than the neceflity of an additional force for pro¬
ducing an efflux through any contraction, even though
it Ihould be fucceeded by a dilatation of the paffage.
Now both the inequalities of the fldes and the undula¬
tions of the motions of each particle are equivalent to a
fucceflion of contractions and dilatations} although each
of thefe is next to infinitely fmall \ their number is alfo
next to infinitely great, and therefore the total eftedt
may be fenfible.
We have hitherto fuppofed that the abfolute velocity
of the particles was not diminifhed: this we did, ha¬
ving affumed that the interval of each undulation of
as angular the fides was without inequalities. But this was gra-
afperities, tuitous : it was alfo gratuitous that the fides were only
undulated. We have no reafon for excluding angular
afperities. Thefe will produce, and moft certainly of¬
ten produce, real diminutions in the velocity of the
contiguous particles •, and this muft extend to the very
axis of the canal, and produce a diminution of the fum
total of motion : and in order to preferve the fame fen¬
fible progreflive motion, a greater force muft be em¬
ployed. This is all that can be meant by faying that
there is a refiftance to the motion of air through long
pipes.
There remains another caufe of diminution, viz. the
perfect flui- want of perfedt fluidity, whether anting from the dif-
dity, feminatidn of folid particles in a real fluid, or from the
vifcidity of the fluid. We (hall not infift on this at pre-
fent, becaufe it cannot be fliown to obtain in air, at
leaf! in any cafe which deferves confideration. It feems
of no importance to determine the motion of air hur¬
rying along with it foot or dull. The efifedt of fogs on
a particular modification of the motion of air will be con-
fidered under the article Sound. What has been faid
on this fubjedl is fufficient "for our purpofe, as explaining
the prodigious and unexpected obftrudtion to the paf¬
fage of air through long and narrow pipes. We are able
to colled! an important maxim from it, viz. that all pipes
of communication flrould be made as wide as circum-
ftances will permit; for it is plain that the obftrudfion
depends on the internal furface, and the force to over¬
come it muft be in proportion to the mafs of mat ter which
is in motion. The firft increafes as the diameter of the
pipe, and the baft as the fquare. The obftrudfion muft
therefore bear a greater proportion to the whole motion
in a fmall pipe than in a large one.
TheTaw ef B were very delirable to know the law by which the
retardation retardation extends from the axis to the fides of the ca-
extending nal, and the proportion which i’ubfifts between the
a xisTtod e Bngths of the canal and the forces neceflary for overcom-
fides of the the obftruaions when the velocity is given; as alfo
canal un~ whether the proportion of the obftrudtion to the whole
known. motion varies with the velocity : but all this is unknown.
It does not, however, feem a defperate cafe in air : we
know pretty diftinctly the law of adtion among its par¬
ticles, viz. that their mutual repulfions are inverfely as
Vol. XVI. Part II.
3®4
and a
want of
A T I C S.
their diftances. This promifes to enable us to trace the
progrefs of undulation from the fides of the canal to the
axis.
We can fee that the retardations will not increafe fo It will not
faft as the fquare of the velocity. Were the fluid in- increafe fo
compreflible, fo that the undulatory path of a particle f,al^as tbe
were invariable, the defledting forces by which each in-
dividual particle is made to defcribe its undulating path ties,
would be precifely fuch as arife from the path itfelf and
the motion in it ; for each particle would be in the fttu-
ation of a body moving along a fixed path. But in a
very compreflible fluid, fuch as air, each particle may be
confidered as a folitary body, adluated by a projedtile
and a tranfverfe force, arifing from the action of the ad¬
joining particles. Its motion muft depend on the ad-
juftment of thefe forces, in the fame manner as the ellip¬
tical motion of a planet depends on the adjuftment of
the force of projediion, with a gravitation inverfely pro-
poriional to the fquare of the diftance from the focus.
The tranfverfe force in the prefent cafe has its origin in
the preflure on the air which is propelling it along the
pipe : this, by fqueezing the particles together, brings
their mutual repulfion into adlion. Now it is the pro¬
perty of a perfedl fluid, that a preflure exerted on any
part of it is propagated equally through the whole fluid ;
therefore the tranfverfe forces which are excited by this
preflure are proportional to the preflure itfelf; and we
know that the preffures exerted on the furface of a fluid,
fo as to expel it through any orifice, or along any canal,
are proportional to the fquares of the velocities which
they produce. Therefore, in every point of the undu¬
latory motion of any particle, the tranfverfe force by
which it is deflected into a curve is pi-oportional to the
fquare of its velocity. When this is the cafe, a body
would continue to deicribe the fame curve as before ;
but, by the very compreflion, the. curvatures are increa-
fed, fuppofing them to remain fimilar. This would re¬
quire an increafe of the tranfverfe forces ; but this is not
to be found: therefore the particle will not defcribe a
limilar curve, but one which is lefs incurvated in all its
parts; confequently the progreflive velocity of the whole,
which is the only thing perceivable by us, will not be fo
much diminiflied ; that is, the obftrudtions will not in¬
creafe fo faft as they would otherwife do, or as the fquarcs
of the velocities.
This reafoning is equally applicable to all fluids, and
is abundantly confirmed by experiments in hydraulics,
as we fhall fee when confidering the motion of rivers.
We have taken this opportunity of delivering our notions
on this fubjeft; becaufe, as we have often faid, it is in
the avowed difcrete conftitution of air that we fee moft
diftinctly the operation of thofe natural powers which
conftitute fluidity in general. 307
We would beg leave to mention a form of experiment
for difcovering the law of retardation with confiderable nXts on
accuracy. Experiments have been made on pipes and pipes and
canals. Mr Boflut, in his Hydrodyncimique, has given canaii
a very beautiful fet made on pipes of an inch and two
inches diameter, and 200 feet long : but although thefe
experiments are very inftruftive, they do not give us
any rule by which we can extend the refult to pipes of
greater length and different diameters.
Let a frnooth cylinder be fet upright in a very large
veffel or pond, and be moveable round its axis : let it be
turr,ed round by means of a wheel and pulley with an
4 Y uniform
Wind.
_3°S
Wind is
air in mo¬
tion.
3°9
The veloci-
722 P N E U M
Velocity of uniform motion and determined velocity. It v/ill ex¬
ert the Tame force on the contiguous water which would
be exerted on it by water turning round it with the
fame velocity : and as this water would ha'fe its motion
gradually retarded by the fixed cylinder, fo the moving
cylinder will gradually communicate motion to the fur¬
rounding water. We Ihould obferve the water gradually
dragged round by it; and the vortex would extend far¬
ther and farther from it as the motion is continued, and
the velocities of the parts of the vortex will be lefs and
lefs as w^e recede from the axis. Now, we apprehend,
that when a point of the furface of the cylinder has moved
over 200 feet, the motion of the water at different dif-
tances from it will be fimilar and proportional to, if not
precifely the fame with, the retardations of water flow¬
ing 200 feet at the fame diilance from the fide of a ca¬
nal : at any rate, the two are fufceptible of an accurate
comparifon, and the lawr of retardation may be accurate¬
ly deduced from obfervations made on the motions of
this vortex.
Air in motion is a very familiar objeff of obfervation j
and it is interefling. In all languages it has got a name j
ive call it wind : and it is only upon reflection that we
confider air as wind in a quiefcent date. Many perfons
hardly know what is meant when air is mentioned ; but
they cannot refufe that the blafl from a bellows is the
expulflon of wdiat they contained \ and thus they learn
that wind is air in motion.
It is of confequence to know the velocity of wind \
Ty of wind but no good and unexceptionable method has been con-
not eafily trived for this purpofe. The bed feems to be by mea-
difcoveied. furjng t.he fpace paffed over by the diadow of a cloud *,
but this is extremely fallacious. In the fird place, it is
certain, that although we fuppofe that the cloud has the
velocity of the air in which it is carried along, this is not
an exafl meafure of the current on the furface of the
earth j we may be almod certain that it is greater : for
air, like all other fluids, is retarded by the fides and bot¬
tom of the channel in which it moves. But, in the next
place, it is very gratuitous to fuppofe, that the velocity
of the cloud is the velocity of the dratum of air between
the cloud and the earth •, we are almod certain that it is
not. It is abundantly proved by Dr Hutton of Edin¬
burgh, that clouds are always formed when two parcels
of air of different temperatures mix together, each con¬
taining a proper quantity of vapour in the date of che¬
mical folution. We know that different drata of air will
frequently dowr in different directions for a long time.
In 17.81 while a great fleet rendezvouzed in Leith
Roads during the Dutch war, there was a brifk eaflerly
wind for about five weeks ; and, during the lad fortnight
of this period, there was a brifk -wederly current at the
'height of about three-fourths of a mile. 'I his was didinft-
ly indicated by frequent fleecy clouds at a great didance
above a lower dratum of thefe clouds, which were driv¬
ing all this time from the eadward. A gentleman who
was at the fiege of Quebec in 1759, informed us, that
one day while there blew a gale from the wed, fo hard
ihat the drips at anchor in the river were obliged to
drike their topmads, and it was with the utmod diffi¬
culty that feme well manned boats could row againd it,
carrying fome artillery dores to a pod above the town,
feveral drells were thrown from the town to dedroy the
boats : one of the fhells burd in the air near the top of
its flight, which was about half a mile high. The
A T I C S.
fmoke of this bomb remained in the fame fpot for above Velocity of
a quarter of an hour, like a great round ball, and gra-, Wind- t
dually diffipated by diffufion, without removing many ~y
yards from its place. When, therefore, two drata of air
come from different quarters, and one of them dows
over the other, it will be only in the contiguous furfaces
that a precipitation of vapour will be made. This will
form a thin fleecy cloud } and it will have a velocity
and direction which neither belongs to the upper nor to
the lower dratum of air wdiich produced it. Should
one of thefe drata come from the ead and the other
from the rved with equal velocities, the cloud formed
between them will have no motion at all } diould one
come from the ead, and the other from the north, the
cloud will move from the north-ead with a greater velo¬
city than either of the drata. So uncertain then is the
information given by the clouds either of the velocity
or the direClion of the wind. A thick fmoke from a
furnace will give us a much lefs equivocal mealirre ; and
this, combined with the effeCts of the wind in impelling
bodies, or defleCling a loaded plane from the perpendicu¬
lar, or other effeCts of this kind, may give us meafures of
the different currents of wflnd with a precifion fufficient
for all practical ufes. _
The celebrated engineer Mr John Smeaton has given, q-heVefuIfe
in the 5id volume of the Philofophical TranfaCtions, theofSmea-
velocities of wind correfponding to the ulual denomina- tons ob-
tions in our language. There are founded on a great
number of obfervations made by himfelf in the courle of
his praCtice in ereCting wind-mills. They aie contained
in the following table.
1
Miles Feet
per hour. per fecono1.
I.47
2-93
4.40
5-871
7-33-3
I4-^7 1
22. s
29-347
36.67^
44-01 L
Sl‘34$
58.68 1
66.01 j
73*351
88.02 s
117.36
146.70
1
2
3
4
5
10
!5
20
25
3°
35
40
45
5°
60
80
100
Names.
Light airs.
Breeze.
Brifk gale.
Fredi gale.
Strong gale.
Hard gale.
Storm.
f Hurricane, tearing up
< trees, overturning build-
tings, &c.
See alfo fome valuable experiments by him on this
fubjeft, Philofophical Tranfactions 1760 and 1761. j
One of the mod ingenious and convenient methods Account of
for meafuring the velocity of the wind is to employ its Dr Lind’s
preffure in fupporting a column of water, in the fame way anemome-
as Mr Pitot meafures the velocity of a current of water. er’
We believe that it was fird propofed by Dr James Lind
of Windfor, a gentleman eminent for his great know¬
ledge in all the branches of natural fcience, and for his
ingenuity in every matter of experiment or praClical ap¬
plication.
His anemometer (as thefe indruments are called) con-Fig. 84,
P N E U M
Velocity ofMs of a glafs tube of the form ABCD (fig. 84.), open
Wind. at bcth ends, and having the branch AB at right angles
to the branch CD. This tube contains a few inches of
water or any fluid (the lighter the better) ; it is held
with the part CD upright, and AB horizontal and in
the direftion of the wind ; that is, with the mouth A
fronting the wind. The wind a£ts in the way of pref-
fure on the air in AB, comprefles it, and caufes it to
prefs on the farface of the liquor ; forcing it down to F,
while it rifes to E in the other leg. The velocity of
the wind is concluded from the difference Ef between
the heights of the liquor in the legs. As the wind does
not generally blow with uniform velocity, the liquor is
apt to dance in the tube, and render the obfervation dif¬
ficult and uncertain : to remedy this, it is proper to con-
trad very much the communication at C between the
two legs. If the tube has half an inch of diameter (and
it fhould not have lefs), a hole of ^ of an inch is large
enough ; indeed the hole can hardly be too fmall, nor
the tubes too large.
It is inge- This inftrument is extremely ingenious, and will un-
nious and doubtedly give the proportions of the velocities of dif-
ufeful. ferent currents with the greateft precifion ; for in what¬
ever way the preffure of wind is produced by its mo¬
tion, we are certain that the different preffures are as the
fquares of the velocities: if, therefore, we can obtain one
certain meafure of the velocity of the wind, and obferve
the degree to which the preffure produced by it raifes
the liquor, we can at all other times obferve the pref¬
fures and compute the velocities from them, making pro¬
per allowances for the temperature and the height of
the mercury in the barometer 5 becaufe the velocity will
be in the fubduplicate ratio of the denfity of the air in-
verfely w'hen the preffure is the fame.
It is ufually concluded, that the velocity of the wind
is that which would be acquired by falling from a height
which is to Ey’as the weight of water is to that of an
equal bulk of air. Thus, fuppofing air to be 840 times
lighter than w^ater, and that Ey is of an inch, the
velocity will be about 63 feet per fecond, wdiich is that
of a very hard gale, approaching to a ftorm. Hence wre
fee by the bye, that the fcale of this inftmment is ex¬
tremely fhort, and that it would be a great improvement
of it to make the leg CD not perpendicular, but very
much Hoping; or perhaps the following form of the
inftrument will give it all the perfection of which it is
Tig. 85. capable. Let the horizontal branch AB (fig. 85.) be
contracted at B, and continued horizontally for feveral
inches EG of a much fmaller bore, and then turned
down for two or three inches GC, and then upwards
with a wide bore. To ufe the inftrument, hold it with
the part DC perpendicular ; and (having fheltered the
mouth A from the wind) pour in water at D till it ad¬
vances along GB to the point B, which is made the
beginning of the fcale ; the water in the upright branch
Handing at f in the fame horizontal line with BG.
Now, turn the mouth A to the wind; the air in AB
will be comprcffed and will force the water along BG
to F, and caufe it to rife fromy'to E; and the range
/E will be to the range BF on the fcale as the fe&ion
of the tube BG to that of CD. Thus, if the width of
DC be 4- an inch, and that of BG we fhall have 25
•inches in the fcale for one inch of real preffure E f.
But it has not been demoaftrated in a very fatisfac-
tory manner, that the velocity of the wind is that ac-
A T 1 C 8. 723
quired by falling through the height of a column of air Velocity of
whofe weight is equal to that of the column of water ^Ir,d’ ,
E f. Experiments made with Pitot’s tube in currents
of water ftiow that feveral corrections are neceffary for
concluding the velocity of the current from the eleva¬
tions in the tube : thefe corrections may however be
made, and fafely applied to the prefent cafe; and then
the inftrument will enable us to conclude the velocity
of the wind immediately, without any fundamental com-
parifon of the elevation, with a velocity actually deter¬
mined upon other principles. The chief ufe which we
have for this information is in our employment of wind
as an impelling power, by which we can aCtuate ma¬
chinery or navigate fhips. Thefe are very important
applications of pneumatical doftrines, and merit a par¬
ticular confideration ; and this naturally brings us to the
laft part of our fubjeCt, viz. the confideration of the im-
pulfe of air on bodies expofed to its aCtion, and the re-
fiftance which it oppofes to the paffage of bodies through
it. . _ 313
This is a fubjeft of the greateft importance ; being This fub-
the foundation of that art which has done the greateftje<ais m°ft
honour to the ingenuity of man, and the greateft fervice
to human fociety, by connecting together the moft dif- f0 difficult*
tant inhabitants of this globe, and making a communi¬
cation of benefits which would otherwife have been im-
poftible ; we mean the art of Navigation or Seamanlhip.
Of all the machines which human art has conftruCted, a
Ihip is not only the greateft and moft magnificent, but
alfo the moft ingenious and intricate; and the clever
feaman poffeffes a knowledge founded on the moft diffi¬
cult and abftrufe doftrines of mechanics. The feaman
probably cannot give any account of his own fcience;
and he poffeffes it rather by a kind of intuition than by
any procefs of reafoning; but the fuccefs and efficacy of
all the mechanifm of this complicated engine, and the
propriety of all the manoeuvres which the feaman prac-
tifes, depend on the invariable laws of mechanics ; and
a thorough knowledge of thefe would enable an intelli¬
gent perfon not only to underftand the machine and the
manner of working it, but to improve both.
Unfortunately this is a fubjeCt of very great difficulty;
and although it has employed the genius of Newton, and
he has confidered it with great care, and his followers
have added more to his labours on this fubjeCt than on
any other, it ftill remains in a very imperfeCt ft ate.
A minute difcuffion of this fubjeCt cannot therefore
be expeCted in a work like this : we muft content our-
felves with fuch a general ftatement of the moft approv¬
ed doCtrine on the fubjeCt as fhall enable our readers to
conceive it diftinCtly, and judge with intelligence and
confidence of the practical deductions which may be
made from it. ^
It is evidently a branch of the general theory of the Impuile
impulfe and refiftance of fluids, which belongs to Hy- and refift-
DRAULics, but will be better underftood when the me- afce
chanical properties of compreffible fluids have been con- air‘
fidered. It was thought very reafonable to fuppofe that
the circumftances of elafticity would introduce the fame
changes in the impulfe and refiftance of fluids that it
does in folid bodies. It would greatly divert the atten¬
tion from the diftinftive properties of air, if we fhould
in this place enter on this fubjeCt, which is both exten-
five and difficult. We reckon it better therefore to take
the whole together : this we fhall do under the article
4 Y a Resistance
7H
Velocity o (RESISTANCE of Fluids, and confine ourfelves at prefent
, Wmd. ^ t0 wjiat reiates to the impulfe and refiftance of air
v alone j anticipating a few of ^the general propofitions
of that theory, but without demonltration, in order to
underftand the applications which may be made of it.
Fig. 86. Suppofe then a plane furface, of which a C (fig. 86.)
is the feftion, expofed to the a ft’, on of a ftream of wind
blowing in the direftion QC, perpendicular to a C.
The motion of the wind will be obftrufted, and the fur-
face a C preffed forward. And as all impulfe or pref-
fure is exerted in a direftion perpendicular to the fur-
face, and is refilled in the oppofite direftion, the furface
will be impelled in the direftion CD, the continuation
of QC. And as the mutual aftions of bodies depend on
their relative motions, the force afting on the furface
a C will be the fame, if wre {hall luppole the air at reit,
and the furface moving equally fwift in the oppofite
direftion. The refiftance of the air to the motion of
the body will be equal to the impulfe of the air in the
former cafe. Thus refiftance and impulfe are equal and
315 contrary.
Air rno- jf t|le aJr moving twice as fall, its particles will
vmg wit -g a (jQubig impulfe ; but in this cafe a double num-
a double . , ' 7 . . . -w- • 1
velocity b61- °f particles will exert their impulle m the lame time:
will gene- the impulfe will therefore be fourfold 5 and in general
rally impel it will be as the fquare of the velocity : or if the air
f Suare of an^ body be both in motion, the impulfe and refiftance
that veto- be proportional to the fquare of the relative velo¬
city. city.
This is the firft propofition on the fubjeft, and it ap¬
pears very confonant to reafon. There will therefore
be fome analogy between the force of the air’s impulfe
or the refiftance of a body, and the weight of a column
of air incumbent on the furface ; for it is a principle
in the aftion of fluids, that the heights of the columns
of fluid are as the fquares of the velocities which their
preffures produce. Accordingly the fecond propofition
is, that the abfolute impulfe of a ftream of air, blowing
perpendicularly on any furface, is equal to the weight
cf a column of air which has that furface for its bafe,
and for its height the fpace through which a body mull
fall in order to acquire the velocity of the air.
Thirdly, Suppofe the furface AC equal to zz C no
longer to be perpendicular to the ftream of air, but in¬
clined to it in the angle ACD, which we fhall call the
angle of incidence; then, by the refolution of forces, it
follows, that the aftion of each particle is diminiftied in
the proportion of radius to the fine of the angle of in¬
cidence, or of AC to AL, AL being perpendicular to
CD.
Again : Draw AK parallel to CD. It is plain that
no air lying farther from CD than K A is will ftrike
the plane. The quantity of impulfe therefore is dimi-
nifhed ftill farther in the proportion ©f a C to KC, or
of AC to AL. Therefore, on the wdiole, the abfolute
impulfe is diminiftied in the proportion of AC* to AL* :
hence the propofition, that the impulfe and refiftance of
a given furface are in the proportion of the fquare of the
fine of the angle of incidence.
Fourthly, This impulfe is in the direftion PL, per¬
pendicular to the impelled, furface, and the furface tends
to move in this direftion : but fuppofe it moveable only
in fome other direftion PO, or that it is in the direftion
PQ that we wifti to employ this impulfe, its aftion is
therefore oblique ; and if we wifti to. know the intenfity
P N E U M A T I C S.
of the impulfe in this direftion, it mull be diminiftied Velocity of
ftill farther in the proportion of radius to the cofine of the Wind,
angle LPO or fine of CPO. Hence the general pro-
polition : The effective impulfe is as the furface, as the
fquare of the velocity of the wind, as the fquare of thefne
of the angle of incidence, and as the fine of the obliquity
jointly, which wre may exprefs by the lymbol R — S'V**
Jin.1- l‘fn. O ; and as the impulfe depends on the den-
fity of the impelling fluid, we may take in every circum-
ftance by the equation R—S'D-V** fn.1 1'fn. Q. If
the impulfe be eftimated in the direftion of the ftream,
the angle of obliquity ACD is the fame with the angle
of incidence, and the impulfe in this direftion is as the
furface, as the iquare of the velocity, and as the cube of
the angle of incidence jointly.
It evidently follows from thefe premifes, that if AC A'
be a wedge, of which the bafe AA' is perpendicular to
the wind, and the angle ACA' bifefted by its direftion,
the direft or perpendicular impulfe on the bafe is to the
oblique impulfe on the fides as radius to the fquare of
the fine of half the angle ACA'.
The fame muft be affirmed of a pyramid or cone
ACA', of which the axis is in the direftion of the
wind.
If ACA' (fig. 87!) reprefent the feftion of a folid, Fig. 87.
produced by the revolution of a curve line APC round
the axis CD, which lies in the direftion of the wfind, the
impulfe on this body may be compared with the direft
impulfe on this bafe, or the refiftance to the motion of
this body through the air may be compared with the
direft refiftance of its bafe, by refolving its furface into
elementary planes P/>, which are coincident wfith a tan¬
gent plane PR, and comparing the impulfe on P/> with
the direft impulfe on the correfponding part K £ of the
bafe.
In this way it follows that the impulfe on a fphere
is one half of the impulfe on its great circle, or on the
bafe of a cylinder of equal diameter.
We ftrall conclude this {ketch of the doftrine with a
very important propofition to determine the moft advan¬
tageous pofition of a plane furface, when required to
move in one direftion while it is impelled by the wind
blowing in a different direftion. Thus, . ,
Let AB (fig. 88.) be the fail of a (hip, CA the di-important
reftion in which the wind blow's, and AD the line of inference
the {hip’s courfe. It is required to place the yard AC from !h,s
in fuch a pofition that the impulfe of the wind upon the do<'rme'
fail may have the greateft effeft poffible in impelling
the {hip along AD.
Let AB, Ab, be two pofitions of the fail very near fig. 88.
the beft pofition, but on oppofite fides of it. Draw7 BE,
b e, perpendicular to C A, and BF, b f perpendicular to
AD, calling AB radius j it is evident that BE, BF,
are the fines of impulfe and obliquity, and that the ef-
feftive impulfe is BE* xBF, ox be1'^bf This muft be
a maximum.
Let the points B, b, continually approach and ulti¬
mately coincide •, the chord b B wall ultimately coincide
with a ftraight line CBD touching the circle in B j the
triangles CBE, c b e are fimilar, as alfo the triangles
DBF, ~Dbf: therefore BE* : Z>f*i=BC* : be1, and
BF : £/r=BD : Z'D *, and BE* X BF : £ e* x £/=CB* X
BD : c b1 X^D. Therefore when AB is in the beft po¬
fition, fo that BE2 x BF is greater than b e1 y. bf, we
{hall have CB x BD greater than Cb1 x£D, or c B* XBD
P' N E II M
Telocity of is alto a maximum. This we know to be the cafe xvhen
Wind. CB=2BD: therefore the fail muft be fo placed that
' 1 the tangent of the angle of incidence ihall be double of
the tangent of the angle of the fail and keel.
In a common windmill the angle CAD is neceffiiriiy
a right angle } for the fail moves in a circle to which
the wind is perpendicular : therefore the belt angle of
the fail and axle will be 54°-44 nearly.
Such is the theory of the reiiilance and impulfe of
the air. It is extremely iimple and of eafy application.
In all phyfical theories there are affumptions which de¬
pend on other principles, and thofe on the judgement of
the natural!It; fo that it is always proper to confront
the theory with experiment. There are even circum-
llances in the prefent cafe which have not been attended
to in the theory. When a ftream of air is obftru£ced by
a folid body, or when a folid body moves along in air,
the air is condenfed before it and rarefied behind. There
is therefore a preffure on the anterior parts arifing from
this want of equilibrium in the elafiicity ot the air.
This muft be fuperadded to the force arising from the
impetus or inertia of the air. We cannot tell with j?re-
ciiion what may be tbe amount oi tins condenfition y
it depends on the velocity with whicn any condensation
ditfufes itfelf.
Alfo, if the motion be fo rapid that the preflure of
the afmofphere cannot make the air immediately occupy
the place quitted by the body, it will fuftain tnis prei-
3T7 fore on its fore part to be added to the other forces.
Account of Experiments on this fobjebt are by no means nume-
the princi- r0us . aj- i[eaft fuch experiments as can be depended on
for the foundation of any practical application. I ne
firft that have this chara&er are thofe publiihed by Mr
Robins in 1742 in his treatife on Gunnery. They were
repeated with lome auditions by the Chevalier Borda,
and fome account of them pubjithed in the Memoirs of
the Academy of Sciences in 1763. In the Philofo-
phical Tranfaftions of the Royal Society of London,
vol. Ixxiii. there are fome experiments of the fame kind
on a larger fcale by Mr Edgeworth. Thefe were, all
made in the way defcribed m our account of IVIr Robins s
improvements in gunnery. Bodies were made to move
with determined velocities, and tne renftances were
meafored by weights.
In all thefe experiments the refiftances were found
very exaftly in the proportion of the fquares of the ve¬
locities y but they were found confiderably gi eater than
the weight of the column of air, whofe height would
produce the velocity in a falling body. Mr.Robins s
experiments on a fquare of 16 inches, defcrioing 2$.2
feet per fecond, indicate the renftance to be to this
weight nearly as 4 to 3. Borda’s experiments on the
fame furface ftate the difproportion ftill greater.
The refiftances are found not to be in the proportion
of the forfaces, but increafe confiderably fafter. Sur¬
faces of 9, 16, 36, and 81 inches, moving with one ve¬
locity, had refiitances in the proportion of 9, I7t? 42ib
and 104-I.
Now as this deviation from the proportion of the for¬
faces increafes with great regularity, it is moft probable
that it continues to increafe in forfaces of ftill greater
extent; and thefe are the moft generally to be met
with in praftice in the aftion of wind on {hips and mills.
Borda’s experiments on 81 inches fliow that the im-
A T I c s. 725
pulfe of wind moving one foot per fecond is about ^ eIocit> of
of a pound on a fquare foot. Therefore to find the , ^ ^d- >
impulfe on a foot correiponding to any velocity, divide
the fquare of the velocity by 500., and we obtain the
impulfe in pounds. Mr Roufe of Leicefterfhire made
many experiments, which are mentioned with great ap¬
probation by Mr Smeaton. His great fagacity and ex¬
perience in the erection of windmills oblige us to pay a
confiderable deference to his judgement. Thefe experi¬
ments confirm our opinion, that the impulfes increafe
fafter than the furfaces. The following table was cal¬
culated from Mr Roufe’s obfervations, and may be con-
fidered as pretty near the truth.
pal experi
merits on
this fub-
ject.
Ve-lo ity
in Feet.
O
lO
20
3°
4°
5°
60
70
80
90
100
1 xo
120
130
140
Impulfe on a
Foot in Pour ds.
0,000
0,229
' 0,915
2,059
3,660
5,718
8,234
11,207
14,638
18,526
22,872 •
27,675
32,926
38,654
44,830
5L462
If we multiply the fquare of the velocity in feet by
16, the product will be the impulfe or refiftance on a
fquare foot in grains, according to Mr Roufe's numbers.
The greateft deviation from the theory occurs in the
oblique impulfes. Mr Robins compared the refiftance
of a wedge, whofe angle was 90°, with the refiftance
of its bafe ; and inftead of finding it lefs in the propor¬
tion of ^2 to 1, as determined by the theory, he found
it greater in the proportion of 55 68 nearly ; and
when he formed the body into a pyramid, of which the
fides had the fame forface and the fame inclination as
the fides of the wedge, the refiftance of the bafe and
face were now as 55 to 39 nearly : fo that here the
fame furface with the fame inclination had its refirtance
reduced from 68 to 39 by being put into this form.
Similar deviations occur in the experiments of the Che¬
valier Borda ; and it may be collefted from both, that
the refiftances diminifh more nearly in the proportion of
the fines of incidence than in the proportion of the
fquares of thofe fines.
The irregularity in the refiftance of curved forfaces
is as great as in plane furfaces. In general, the theory
gives the oblique impulfes on plane forfaces much too
finall, and the impulfes en curved forfaces too great.
The refiftance of a fphere does not exceed the fourth
part of the refiftance of its great circle, inftead of being
its half; but the anomaly is foch as to leave hardly any
room for calculation. It would be very defirable to
have the experiments on this fobjeft repeated in a great¬
er variety of cafes, and on larger forfaces, fo that the,
errors of the experiments may be of lefs confequence*.
Till
725 PNEUMATICS.
Refiftance Till tills matter be reduced to fome rule, the art of
working (hips mult remain very imperfeft, as muft alfo
the conftruction of windmills.
The cafe in which we are moft interefted in the
knowledge of the refiftance of the air is the motion of
bullets and fhells. Writers on artillery have long been
~ ' It
of Air in
Gunnery.
.318
It is of
great con-
of air in
the motion fn
of bullets,
&c.
knowThe10 ^en^ble of the great effect of the air’s refiftance
refiftance feems to have been this confideration that chiefly enga¬
ged Sir Ifaac Newton to confider the motions of bodies
in a refifting medium. A propofttion or two would
have fufficed for fhowing the incompatibility of the pla¬
netary motions with the fuppofition that the celeftial
fpaces were filled with a fluid matter 5 but he has with
great folicitude confidered the motion of a body pro¬
jected on the furface of the earth, and its deviation
from the parabolic track afligned by Galileo. He has
bellowed more pains on this problem than any other in
his whole work •, and his inveftigation has pointed out
almoft all the improvements which have been made in
the application of mathematical knowledge to the ftudy
of nature. Nowhere does his fagacity and fertility of
refource appear in fo ftrong a light as in the fecond
book of the Princiftia, which is almoft wholly occupied
by this problem. The celebrated mathematician John
Bernouilli engaged in it as the fineft opportunity of dlf-
playing his fuperiority. A miftake committed by New¬
ton in his attempt to a folution was matter of triumph
to him j and the whole of his performance, though a
piece of elegant and elaborate geometry, is greatly hurt
by his continually bringing this miftake (which is a
mere trifle) into view. The difficulty of the fubjedt is
fo great, that fubfequent mathematicians feem to have
kept aloof from it; and it has been entirely overlooked
by the many voluminous writers who have treated pro-
fefledly on military projedtiles. They have fpoken in¬
deed of the refiftance of the air as affedting the flight of
fhot, but have faved themfelves from the tafk of invef-
tigating this effeCt (a tafk to which they were unequal),
by fuppofing that it was not fo great as to render their
theories and practical deductions very erroneous. Mr
Robins was the firft who ferioufly examined the fubjeCt.
He ffiowed, that even the Newtonian theory (which had
been corrected, but not in the fmalleft degree improved
or extended in its principles) was fufficient to fhow
that the path of a cannon ball could not refemble a pa¬
rabola. Even this theory ffiowed that the refiftance was
more than eight times the weight of the ball, and ffiould
produce a greater deviation from the parabola than the
parabola deviated from a ftraight line.
This fimple but ftngular obfervation was a ftrong
proof how faulty the profeffed writers on artillery had
w!'j1terS been, in rather amufing themfelves with elegant but ufe-
in this re- ^ applications of eafy geometry, than in endeavouring
to give their readers any ufeful information. He add¬
ed, that the difference between the ranges by the New¬
tonian theory and by experiment was fo great, that
the refiftance of the air muft be vaftly fuperior to what
that theory fuppofed. It was this which fuggefted to
him the neceffity of experiments to afcertain this point.
We have feen the refult of thefe experiments in mode¬
rate velocities *, and that they were fufficient for calling
the whole theory in queftion, or at leaft for rendering it
ufelefs. It became neceffary therefore to fettle every
point by means of a direCt experiment. Here was a
great difficulty. How {hall we meafure either thefe
3
3)9
The igno
ranee of
the writers
fpedt.
great velocities which are obferved in the motions of Refiftance'
cannon-fhot, or the refiftances which thefe enormous Ajr in
velocities occafion ? Mr Robins had the ingenuity to do ,
both. The method which he took for meafuring the ve¬
locity of a mufket-ball was quite original •, and it was
fufceptible of great accuracy. We have already given
an account of it under the article Gunnery. Having
gained this point, the other was not difficult. In the
moderate velocities he had determined the refiftances by
the forces which balanced them, the weights which kept
the refifted body in a ftate of uniform motion. In the
great velocities, he propofed to determine the refiftances
by their immediate effects, by the retardations which they
occafioned. This was to be done by firft afeertaining
the velocity of the ball, and then meafuring its velocity
after it had pafled through a certain quantity of air. The
difference of thefe velocities is the retardation, and the
proper meafure of the refiftance •, for, by the initial and
final velocities of the ball, we learn the time which wTas
employed in paffing through this air with the medium
velocity. In this time the air’s refiftance diminifhed the
velocity by a certain quantity. Compare this with the
velocity which a body projected directly upwards would
lofe in the fame time by the refiftance of gravity. The
two forces muft be in the proportion of their effeefts.
Thus we learn the proportion of the refiftance of the air
to the weight of the ball. It is indeed true, that the
time of paffing through this fpace is not accurately had
by taking the arithmetical medium of the initial and
final velocities, nor does the refiftance deduced from this
calculation accurately correfpond to this mean velocity j
but both may be accurately found by the experiment by
a very troublefome computation, as is ffiown in the 5th
and 6th propofitions of the fecond book of Newton’s
Principia. The difference between the quantities thus
found and thofe deduced from the fimple procefs is quite
trifling, and far within the limits of accuracy attain¬
able in experiments of this kind} it may therefore be
fafely neglefted.
Mr Robins made many experiments on this fubje£t $ Mr Robins
but unfortunately he has publifhed only a very few, fuch made many
as were fufficient for afeertaining the point he had inexPeri-
view. He intended a regular w7ork on the fubjedt, in
which the gradual variations of refiftance correfponding je(^>
to different velocities fhould all be determined by expe¬
riment : but he was then newly engaged in an import¬
ant and laborious employment, as chief engineer to the
Eaft India Company, in whofe fervice he went out to
India, where he died in lefs than two years. It is to be
regretted that no perfon has profecuted thefe experiments.
It would be neither laborious nor difficult, and would
add more to the improvement of artillery than any thing
that has been done fince P\Ir Robins’s death, if we except
the profecution of his experiments on the initial veloci¬
ties of cannon-fhot by Dr Charles Hutton royal profeffor
at the Woolwich Academy. It is to be hoped that this
gentleman, after having with fuch effedt and fuccefs ex¬
tended Mr Robins’s experiments on the initial velocities
of mufket-fhot to cannon, will take up this other fubjedt,
and thus give the art of artillery all the fcientific foun¬
dation which it can receive in the prefent ftate of our
mathematical knowledge. Till then we muft content
ourfelves with the pradtical rules which Robins has de¬
duced from his own experiments. As he has not given
us the mode of dedudtion, we muft compare the refults
with
PNEUMATICS.
727
Sefiftance
of Air in
Ounnery.
General re-
fait of
them, See.
32a
Partly con¬
troverted
by Euler,
but with¬
out fuffi-
cient
ground?.
with experiment. He lias indeed given a very extenfiye
edmparifon with the numerous experiments made both in
Britain and on the continent; and the agreement is very
great. His learned commentator Euler has been at.no
pains to inveftigate thele rules, and has employea him-
felf chiefly in detefting errors, moft of which are fup-
pofed, becaufe he takes for a limfhed work what IMr
Robins only gives to the public as a hally but uftiul
Iketch of a new and very difficult branch of fcience.
The general refult of Robins’s experiments on the re¬
tardation of mufket-lhot is, that although in moderate
velocities the refiftance is fo nearly in the duplicate pro¬
portion of the velocities that we cannot obferve any de¬
viation, yet in velocities exceeding 200 feet.per fecond
the retardations increafe falter, and the deviation from
this rate increafes rapidly with the velocity. He afenbes
this to the caufes already mentioned, viz. the condenfa-
tion of the air before the ball and to the rarefaction be¬
hind, in confequence of the air not immediately occu-
pying the lb ace left by the bullet. Lhis incieaie is fo
great*, that if the refiftance to a ball moving with the
velocity of 1700 feet in a fecond be computed on the
fuppofition that the refiftance obferved in moderate ve¬
locities is increafed in the duplicate ratio of the velocity,
it will be found hardly one-third part of its real quanti¬
ty. He found, for inftance, that a ball moving through
-1670 feet in a fecond loft about 1 25 feet per fecond of its
velocity in palling through 50 feet of air. this it mull
have done in the yV of a fecond, in which time it would
have loft one foot if projeded diredly upwards; from which
it appears that the refiftance was about 125 times its
weight, and more than three times greater than it it had
increafed from the refiftance in fmall velocities in the du¬
plicate ratio of the velocities. He relates other experi¬
ments which ffiow fimilar refults.
But he alfo mentions a Angular circumftance, that till
the velocities exceed 1100 feet per fecond, the refiftan-
ces increafe pretty regularly, in a ratio exceeding the
duplicate ratio of the velocities } but that in greatei ve¬
locities the refiftances become fuddenly triple of what
they would have been, even according to this lawT of in¬
creafe. He thinks this explicable by the vacuum which
is then left behind the ball., it being well known that
air rufhes into a vacuum with the velocity of 1132 h:et
per fecond nearly. Mr Euler controverts this conclu-
fion, as inconfiftent with that gradation which is obferved
in all the operations of nature •, and fays, that although
the vacuum is not produced in fmaller velocities than
this, the air behind the ball muft be fo rare.(the fpace
being but imperfettly filled), that the preffure on the
anterior part of the ball muft gradually approximate to
that preffure which an abfolute vacuum would produce;
but this is like his other criticifms. Robins does no¬
where affert that this hidden change of refiftance hap¬
pens in the tranfition of the velocity from 1132 feet to
tliat of 1131 feet 11 inches or the like, but only .that
it is very hidden and very great. It may be ftricftiy
demonftrated, that fuch a change muft happen in a nar¬
row enough limit of velocities to juftify the appellation
of hidden : a fimilar fa£t may be obferved in the motion
of a folid through water. If it be gradually accelera¬
ted, the water will be found nearly to fill up its place,
till the velocity arrives at a certain magnitude, corre-
fponding to the immerfion of the body in the water *,
and then the fmalleft augmentation of its motion imme¬
diately produces a void behind it, into which the water
ruffies in a violent manner and is dallied into froth. A.
gentleman, who has had many opportunities for fuch ob-. 1  ^ ...n 1
iervations, affures us, that when Handing near, the line ot
dire£lion of a cannon difeharging a bail with a large
allotment of powder, fo that the initial velocity certain¬
ly exceeded 1100 feet per fecond, he ahvays obferved a
very fudden diminution of the noiie wffiich the bullet
made during its paffage. Although the ball w’as coming
towards him, and therefore its noife, if equable, wuuld.
be continually increafing, he obferved that it was loudeft
at firft. That this continued for a fecond or two, and
fuddenly diminilhed, changing to a found wffiich was
not only weaker, but dift'ered in kind, and gradually in¬
creafed as the bullet approached him. He laid, that the
firft noife was like the hilling of red-hot iron in water,
and that the fubfequent noife rather refembled a hazy
whittling. Such a change of found is a neceffary confe¬
quence of the different agitation of the air in the twTo
cafes. We know alfo, that air rulhing into a void,, as
when we break an exhaufted bottle, makes a report like
a mulkel.
Mr Robins’s affertion therefore has every argument
for its truth that the nature of the thing will, admit.
But we are not left to this vague reafoning : his expe¬
riments (how us this diminution of refiftance. It clear¬
ly appears from them, that in a velocitj of 1700 feet
the refiftance is more than three times the refiftance de¬
termined by the theory wffiich he fuppofes the common
one. When the velocity was 1065 feet, the actual re¬
fiftance was V of the theoretical; and when the velo¬
city was 400 feet, the aftual refiftance was about 4 of
the theoretical. That he affumed a theory of refiftance
wffiich gave them all too fmall, is of no confequence in
the prefent argument. 323 .
Mr Robins, in fumming up the refults of his obler- Rule by
vations on this fubjeft, gives a rule very eafily remem-Robins for
bered for computing the refiftances to tno.ie very ra_P1<^rey1^ances
motions. It has been already mentioned in tne article an(j very
Gunnery, but we repeat it here, in order to accommo-rapid mo-
date it to the quantities which have been determined in tons,
fome degree by experiment.
A C B D
Let AB reprefent the velocity of 1700 feet per fecond,
and AC any other velocity. Make BD to A.U as the
refiftance given by the ordinary theory to the refiftance
actually obferved in the velocity 1700: then will CD
he to AD as the refiftance afligned by the ordinary
theory to the velocity AC is to that which really corre-
fponds to it.
To accommodate this to experiment, recolleft * that a * See Gmz~
fphere of the fize of a 1 2 pound iron (hot, moving 25 feet nery, n0 iy.
in a fecond, had a refiftance of of a pound. Augment&c-
this in the ratio of 25* to 17001, and w^e obtain .210
nearly for the theoretical refiftance to this velocity ;
but by comparing its diameter of 4^ inches with £, the
diameter of the leaden ball, which had a refiftance of at
lead 11 pounds with this velocity, we conclude that the
12 pound (hot would have had a refiftance of 396 pounds:
therefore BD ; ADi=;2io : 39^’ anc^ AB : AD—186 .
396; and AB being 1700, AD will be 3613.
Let ADrrtf, AC=x, and let R be the refiftance to a
12 pound iron (hot moving one foot per fecond, and
r the refiftance (in pounds) wanted for the velocity x ;
'28
Undulation ^ x‘‘
of Air. tve have r—R—I—
PNEUMATICS.
Mr Robins’s expeiiments give
R
—7-- very neatly. This gives R^rr 0,263235,
which is nearly one fourth. Thus our formula becomes
O.263235 A*
or very nearly
x1
fallii
3613—a 7 ^ 4(3613—a)’
fiiort of the truth about Toth part. The fimplicity of
the formula recommends it to our ufe, and when we in-
creafe its refult it is incomparably nearer to the
true refult of the theory as corrected by Mr Robins than
we can hope that the theory is to the aftual refiftance.
We can eafily fee that Mr Robins’s correction is only a
fagacious approximation. If we fuppofe the velocity 3613
feet, a very pollible thing, the re 11 dance by this formula
is infinite, which cannot be. We may even fuppofe that
the refiltance given by the formula is near the truth only
ur fuch velocities as do not greatly exceed 1700 feet
per fecond. No military projectile exceeds 2200,
and it is great folly to make it lo great, becaufe it is
reduced to 1700 almoft in an inftant, by the enormous
refiftance.
The refiftance to other balls will be made by taking
^ them in the duplicate ratio of the diameters.
The difcuf- It has been already obferved, that the firft mathema-
fions of ma-ticiansof Europe have lately employed themfelves in im-
"ns not eaf proving this theory of the motion of bodies in a refift-
ly applied. me^um ’ but their difcuffions are fuch as few ar-
tillerifts can underhand. The problem can only be
folved by approximation, and this by the quadrature of
very complicated curves. They have not been able
therefore to deduce from them any practical rules of
325 ealy application, and have been obliged to compute
Borda’s and tables fuited to different cafes. Of thefe performances,
c^arentl ^ Chevalier Rorda, in the Memoirs of the A-
thf beft^ ca.dfmy Sciences for 1769, feems the belt adapted to
military readers, and the tables are undoubtedly of con-
fide/able ufe 5 but it is not too much to fay, that the
fimple rules of Mr Robins are of as much fervice, and
are more eafily remembered : befides, it muft be obfer¬
ved, that the nature of military fervice does not give
room for the application of any very precife rule. The
only advantage that we can derive from a perfeft theory
would be an improvement in the conftruftion of pieces
of ordnance, and a more judicious appropriation of certain
velocities to certain purpofes. The fervice of a gun or
326 mortar muft always be regulated by the eye.
Undulation There is another motion of which air and other elaftic
of air. fluids are fufceptible, viz. an internal vibration of their
particles, or undulation, by which any extended portion
of air is diftributed into alternate parcels of condenfed
and rarefied air, which are continually changing their
condition without changing their places. By this change
the condenfation which is produced in one part of the air
is gradually transferred along the mafs of air to the great-
eft diftances in all dire&ions. It is of importance to have
fome diftinft conception of this motion. It is found to
be by this means that diftant bodies produce in us the
fenfation of found. See Acoustics. Sir Ifaac Newton
treated this fubjecl with his accuftomed ingenuity, and
has given us a theory of it in the end «f the fecond book
of his Principia. This theory has been objected to with
refpedb to the condudt of the argument, and other expla¬
nations have been given by the moft eminent mathema-
iicians. Though they appear to differ from Newton’s,
their refults are precifely the fame ; but, on a clofe exa- Undulation
minaaon, they differ no more than John Bernouhii’s of Air.
tneoiem of centripetal forces difters from Newton’s w 1
viz. the one being expreffed by geometry and the other
by literal analyfis. The celebrated De la Grange redu¬
ces Newton’s inveftigation to a tautological propofition
or identical equation-, but Mr Young of Trinity colic <re,
Dublin, has, by a different turn of expreffion, freed New¬
ton’s method from this objedlion. We ftiall not repeat
it here, but refer our mathematical readers to the article
Acoustics, as it is notour bufinefs at prefent to confider
its connedlion with found.
, Bl.lt fmce Newton publiftied this theory of aerial un- HasWn
dulations, and of their propagation along the air, andufedtoex-
imee the theory has been lo corredfted and improved asP ain a va-
to be received by the moft accurate philofopbers as a ritt>'ofna-
branch of natural philofophy fufceptible of rigid de-tUla! phe’
monftration, it has been freely reforted to by many
writers on other parts of natural fcience, who did not
profefs to be mathematicians, but made ufe of it for
explaining pnenomena in their own line on the autho¬
rity of the mathematicians themfelves. Learning from
them that this vibration, and the quaquaverfum propa¬
gation of the pulfes, were the neceffary properties of an
elaftic fluid, and that the rapidity of this propagation
had a certain affignable proportion to the elafticity and
denfity of the fluid, they freely made ufe of thefe com-
ceflions, and have introduced daftic vibrating fluids in¬
to. many fafts, where others would fufpeci no fuch
thing, and have attempted to explain by their means
many abftrufe phenomena of nature. Alt hers are every¬
where introduced, endued with great elafticity and te-
nuity. \ ibrations and pulfes are fuppoied m this aether
and thefe are offered as explanations. The dodrines
of animal fpirits and nervous fluids, and the whole
mechanical lyftem of Hartley, by which the operations
ot the foul are faid to be explained, have their foun¬
dation in this theory of aerial undulations. If thefe
fancied fluids, and their internal vibrations, really one-
rate in the phenomena aferibed to them, any explana¬
tion that can be given of the phenomena from this
principle muft be nothing elte than fhowing that the
legitimate confequences of thefe undulations are fimllar
to. the phenomena.5 or, if we are no more able to fee
this laft ftep than in the cafe of found (which wre know
to be one confequence of the aerial undulations, although
we cannot tell how), we muft be able to point out, as in
the cafe of found, certain conftant relations between
the general law7s of thefe undulations and the general
laws of the phenomena. It is only in this way that we
think ounelves intitled to fay that the aerial undulations
are caufes, though not the only caufes, of found; and
it is becaufe there is no fuch relation, but, on the con¬
trary, a total diflimilarity, lo be obferved between the
law's of elaftic undulations and the laws of the propaga¬
tion of light, that wre affert with confidence that ethe¬
real undulations are not the caufes of vifion.
Explanations of this, kind fuppofe, therefore, in theBuEthe a»-
firft place, that the pbilofopher who propofes them un-plication ‘
derftands precifely the nature of thefe undulations ; not being
the next place, that he makes his reader fenfible ofmalle.with
thofe circumftances of them which are concerned in thej^ifion
effedl to be explained; and, in the third place, that ' ’
he makes the reader underftand how7 this circumftance
of the. vibrating fluid is conne&ed with the phenome-
non? either by (bowing it to be its mechanical caufie,
pneumatics
729
of Air.
Undulation as when the philofopher explains the refounding ef a
‘' mufical chord to a flute or pipe which gave the lame
' tone 5 or by showing that this circumftance ol the un¬
dulation alwavs accompanies the phenomenon, as when
the philofopher (hows that 233 vibrations or air m a
fecond, in whatever-manner or by whatever cauie they
■ are produced always are followed by the fenfation of
the tone C in the middle of the harpfichord.
• But here we muft obferve, that, with the exception
of Euler’s unfuccefsful attempt to explain the optical
phenomena by the undulations of ether, we have met
with no explanation of natural phenomena, by means of
elaftic and vibrating fluids, where the. author has. to
much as attempted any one of thefe three things, to m-
difpenfably requifite in a logical explanation. Ihey
have talked of vibrations without defcribing them, or
giving the reader the leaf! notion of what kind they are-,
and in no inftance that we can recollea. have they
fhowed how fuch vibrations could have any influence m
the ohenomenon. Indeed, by not defcribing with pre-
ciflon the undulations, they were freed from the tal^ ot
{bowing them to be mechanical caufes of the pnenome-
non and when any of them ftiow- any analogy between
the general laws of elaftic undulations and the general
laws" of the phenomenon, the analogy is fo vague, mdi-
Itina, or partial, that no perfon of common prudence
.would receive it as argument in any cafe in which he
was much interefted. • n. 1 • n
. We think it our duty to remonftrate agamtt this i.o-
venly way of w-riting : we would even hold it up to re¬
probation. It has been chiefly on this faithlefs founda¬
tion that the blind vanity of men has railed that de¬
grading fvftem of opinions called Materialism, by
which the affedlions and faculties of the foul of man have
been refolved into vibrations and pulfes of ether.
We alfo think it our duty to give fome account 6t
tiofofT,: this motion of elaftic fluids. It mull be fuch an account
ftic fluids, as {hall be underftood by thole who are not mathemati¬
cians, becaufe thole only are in danger of being mifled
- by the improper application of them. Mathematical
difcuflion is, however, unavoidable m a fubjeft purely
mathematical -, but we (hall introduce nothing that may
not be eafily underftood or. confided m j and we tiui
that mathematical readers, will excufe us for a mode ot
reafoning which appears to them lax and inelegant
331 Ylm firft thing incumbent on us is to ftiow how elaftic
^ from fluids differ from the unelaftic in the propagation of any
unelaftic agitation of their parts. When a long tube is filled
fluids in with water, and any one part of it puthed out ot its
place, the whole is inftautly moved like a fohd ma s.
But this is not the cafe with air. If a door be mdden y
{hut, the window at the farther end of a long and clcfe
room will rattle 5 but fome time will elapfe between the
(hutting of the door and the motion of the window.
If fome light duft be lying on a braced drum,, and an¬
other be violently beat at a little diftance from it, an at¬
tentive obferver will fee the duft dance up from the
parchment; but this will be at the mftant he hears the
found of the ftroke on the other drum and a fenfible
time after the ftroke. Many fuch familiar faffs fliow
that the agitation is gradually communicated along the
air and therefore that when one particle is agitated by
any fenfible motion, a finite time, however fmall, mutt
elanfe before the adjoining particle is agitated m the
fame manner. This would not be the cafe in watei u
VOL. XVI. Part II.
water be perfeffly incompreflible. We think that this Undulation
may be made intelligible with very little ticuble. t ^ 1
A a
B b
D
3*9
has be¬
come the
foundation
of mate-
rialifm.
330
Of the mo-
propaga¬
ting any
agitation
of their
parts.
Let A, B, C, D, &c, be a row of aerial particles,
at fuch diftances that their elafticity juft balances the
preffure of the atmofphere } and let us fuppofe (as is
deducible from the obferved denffty of air being, pro¬
portional to the comprefling force) that the elafticity of
the particles, by wkich they keep each other at a dft-
tance, is as their diftances inverfely. Let us farther fup¬
pofe that the particle A has been carried, with an. uni¬
form motion, to a by fome external force. It is evident
that B cannot remain in its prelent ftate -, for being
now nearer to a than to C, it is propelled towards C by
the excefs of the elafticity of A above the natural elafti¬
city of C. Let E be the natural elafticity ^ of the par¬
ticles, or the force correfponding to the diftance LC or
BA, and let F be the force which impels B towards
C, and let / be the force exerted by A -when at a.
We have
E : f-Ka : BC, =B a BA;
and E E=B a : BA—B azzB a
of E : E^: B <2 : A. a.
Aa ;
Now in fig. 89. let ABC be the line joining three Fig. S9.
particles, to which draw EG, PH parallel, and IA1,
HBG perpendicular. Take IF or HG to reprefent the
elailicity correfponding to the diitance AB.. Bet the
particle A be fuppofed to have been carried with an uni¬
form motion to a by fome external force, and diaw
R <7 M perpendicular to RG, and make FI : RM—
B a : BA. We fhall then have FI : PM=B a : A a;
and PM will reprefent the force with which the particle
B is urged towards C. Suppofe this conftruffion to be
made for every point of the line AB, and that a point
M is thus determined for each of them, mathematicians
know that all thefe points M lie in the curve of a hy¬
perbola, of which EG and GH are the afymptotes. It
is alfo known by the elements oi mechanics, that fince
the motion of A along AB is uniform, A a or IP may
be taken to reprefent the time of defcribing A a ; and
that the area IPM reprefents the whole velocLy which
B has acquired in its motion towards C when A has
come to a, the force urging B being always as the por¬
tion PM of the ordinate.
Take GX of any length in HG produced, and let
GX reprefent the velocity which the uniform affion of
the natural elafticity IF could communicate to the par¬
ticle B during the time that A would uniformly defcribe
AB. Make GX to GY as the reffangle IFGK to the
hyperbolic fpace IFRM, and draw YS cutting MR pro¬
duced in S, and draw EX cutting MR.in ff.. It is
known to the mathematicians that the point S is in a
curve line FS s called the logarithmic curve; of which
the leading property is, that any line RS paiallel to
GX is to GX as the reffangle IFGH is to the hy¬
perbolic fpace IFRM, and that IX touches the curve
in F. .
This being the cafe, it is plain, .that becaufe RT in-
creafes in the fame proportion with FR, or with the
reffangle IFRP, and RS increafes in the proportion of
the fpace IFRM, TS increafes in the proportion of the
fpace IPM. Therefore TS is proportional to the velocity
^ 4 Z • - of
730 PNEUMATICS.
VJndulatioa of B when A has reached d, and RT is proportional to
, ^ir' , the velocity which the uniform action of the natural
eiafticity would Communicate to B in the fame time.
Then hnce FT is as the time, and TS is as the velocity,
the area FTS will be as the fpace deferibed by B
(urged by the variable force PM) 5 while A, urged by
the external force, deferibes A a; and the triangle
FRT will reprefent the fpace which the uniform aflion
of the natural eiafticity would caufe B to deferibe in the
fame time.
And thus it is plain that thefe three motions can be
compared together : the uniform motion of the agitated
particle A, the uniformly accelerated motion which the
natural eiafticity -would communicate to B by its con-
ftant aftion, and the motion produced in B by the agi¬
tation of A. But this comparifon, requiring the qua¬
drature of the hyperbola and logarithmic curve, would
lead us into moft intricate and tedious computations.
Of thefe we need only give the refult, and make fome
other comparifons which are palpable.
Let Art be fuppofed indefinitely fmall in comparifon
of AB. The fpace deferibed by A is therefore inde¬
finitely fmall; but in this cafe we know that the ratio
of the fpace FRT to the reftangle IFRP is indefinitely
Irnall. There is therefore no comparifon between the
agitation of A by the external force, and the agitation
which natural eiafticity would produce on a fingle par¬
ticle in the fame time, the laft being incomparably
imaller than the firft. And this fpace FRT is incompa¬
rably greater than FTS ; and therefore the fpace which
B would deferibe by the uniform adlion of the natural
eiafticity is incomparably greater than what it would de¬
feribe in confequence of the agitation of A.
From this reafoning we fee evidently that A muft be
fenfibly moved, or a finite or meafurable time muft elapfe
before B acquires a meafurable motion. In like manner
B muft move during a meafurable time before C ac¬
quires a meafurable motion, &c. ; and therefore the
agitation of A is communicated to the diftant particles
in gradual fucceftion.
By a farther comparifon of thefe fpaces we learn the
time in which each fucceeding particle acquires the very
agitation of A. If the particles B and C only are con-
fidered, and the motion of C neglefted, it will be found
that B has acquired the motion of A a little before it
has deferibed \ of the fpace deferibed by A 5 but if the
motion of C be confidered, the acceleration of B muft;
be mcreafed by the retreat of C, and B muft deferibe a
greater fpace in proportion to that deferibed by A. By
computation it appears, that when both B and C have
acquired the velocity of A, B has deferibed nearly 4 of
A’s motion, and C more nearly y. Extending this to
D, we fhall find that D has deferibed ftill more nearly
y of A’s motion. And from the nature of the compu¬
tation it appears that this approximation goes on rapid¬
ly : therefore, fuppofing it accurate from the very firft
particle, it follows from the equable motion of A, that
each fucceeding particle moves through an equal fpace
in acquiring the motion of A.
The conclufion which we muft draw from all this is,
that when the agitation of A has been fully communi¬
cated to a particle at a fenfible difiance, the intervening
particles, all moving forward with a common velocity,
are equally comprefled as to fenfe, except a very few of
the firft: particles j and that this communication, or this
propagation of the original agitation, goes on with an Undulation
uniform velocity. of Air.
Thefe computations need not be attended to by fuch
as do not with for an accurate knowledge of the precife
agitation of each particle. It is enough for fuch
readers to fee clearly that time mujl efcape between the
agitation of A and that of a diftant particle 5 and this
is abundantly manifeft from the incomparability (excufe
the term) of the nafeent redtangle IFRP with the naf-
cent triangle FRT, and the incomparability of FRT
with FTS.
What has now been fhown of the communication of
any fenfible motion A a mull hold equally with refpeft
to any change of this motion. Therefore if a tremulous
motion of a body, fuch as a fpring or bell, fhould agi¬
tate the adjoining particle A by puthing it forward in
tile diredlion AB, and then allowing it to come back
again in the diretftion BA, an agitation fimilar to this
will take place in all the particles of the row one after
the other. Now if this body vibrate according to the Ne-u ton's
law of motion of a pendulum vibrating in a cycloid, the denionftra-
neighbouring particle of air will ofnecejjity vibrate indononthb
the fame manner 5 and then Newton’s demonftration in aAa/as
art. Acoustics needs no apology. Its only deficiency ^oesj *
was, that it feemed to prove that this would be the way "
in which every particle would of neceflity vibrate ;
which is not true, for the fucceflive parcels of air will
be differently agitated according to the original agita¬
tion. Newton only wants to prove the uniform propa¬
gation of the agitations, and he felefts that form which
renders the proof eafieft. Fie proves, in the moft unex¬
ceptionable manner, that if the particles of a pulfe of
air are really moving like a cycloidal pendulum, the
forces a£Hng on each particle, in confequence of the
compreffxon and dilatation of the different parts of the
pulfe, are precifely fuch as are neceffary for continuing
this motion, and therefore no other forces are required.
Then fince each particle is in a certain part of its path,
is moving in a certain direftion, and with a certain ve¬
locity, and urged by a determined force, it mujl move
in that very manner. The objeflion ftarted by John
Bernouilli againft Newton’s demonftration (in a fingle
line) of the elliptical motion of a body urged by a force
in the inverfe duplicate ratio of the diffance from the
focus, is precifely the fame with the objeftion againft:
Newton’s demonftration of the progrefs of aerial undu¬
lations, and is equally futile.
It muft, however, be obferved, that Newton’s demon¬
ftration proceeds on the fuppofition that the linear agita¬
tions of a particle are incomparably fmaller than the ex¬
tent of an undulation. This is not ftridlly the cafe in
any inftance, and in many it is far from being true. In
a pretty ftrong twang of a harpfichord wire, the agita¬
tion of a particle may be near the 50th part of the ex¬
tent of the undulation. This muft difturb the regula¬
rity of the motion, and caufe the agitations in the re¬
mote undulations to differ from thofe in the firft pulfe.
In the explofion of a cannon, the breaking of an ex-
haufted bottle, and many inftances which may be given,
the agitations are ftill greater. The commentators on
Newton’s P?-iucipia, Le Sueur and Jacquier, have fhown,
and Euler more clearly, that when the original agita¬
tions are very violent, the particles of air will acquire a
fubordinate vibration compounded with the regular cy¬
cloidal vibration^ and the progrefs of the pulfes will be
fome what
333
It is
ftrengthen
P N E U M
UnduHtion fomewhat more rapid ; but the intiicacy of the calculus
of Air. js f0 great, that they have not been able to determine
i ~ wJth any tolerable precifion what the change ot velocity
will be. .
i\.ll this, however, is fully confirmed by experiment
  0n founds. The found of a cannon at 10 or 20 miles
ed by com- d^ance Jogg not in the leaft referable its found when
panng tb£ neaf_ Jn thI$ cafe k is a ioud inftantaneous crack, to
cannon which we can afhgn no mufical pitch : at a diftance, it
near and at Js a grave found, of which we can tell the note j and it
a diftance. begins foftly, fwells to its greateft loudnefs, and then
dies away growling. The fame may be faid of a clap
of thunder, which we know to be a loud fnap of ftill
lefs duration. It is highly probable that the appreciable
tones which thofe diftant founds afford are produced by
the continuance of thefe fubordinate vibrations whicn
are added together and fortified in the fucceflive pulfes,
though not perceptible in the firff, in a way fomewhat
refembling the refonance of a mufical chord. Newton’s
explanation gathers evidence therefore from this cir-
cumftance. And we mult further obferve, that all ela-
ilic bodies tremble or vibrate almoft precifejy as a pen¬
dulum fwinging in a cycloid, unlefs their vibrations are
uncommonly violentin which cafe they are quickly re¬
duced to a moderate quantity by the refiftance of the
air. The only very loud founds which we can produce
in this way are from great bells } and in thefe the ut-
jnoft extent of the vibration is very fmall in companfqn
with the breadth of the pulfe. The velocity of thefe
founds has not been compared with that ^of cannon,, or
perhaps it would be found lefs, and an obje£Hon a gain ft
Newton’s determination removed. He gives 969 feet
per fecond, Exaeriment 1142.
TheaEita But it is alfo very probable, that in the propagation
tion in all through the air, the agitation gradually and rapidly ap-
probability proaches to this regular cycloidal form m the meet dive
pulfes, in the fame way as we obferve that whatever is
the form of agitation in the middle of a fmooth p nd or
water, the fpreading circles ate always of one gentle
form without afperities. In like manner, into whatever
form we throw a flretched cord by the twang which we
wive it, it almoft immediately makes fmooth undulations,
keeping itfelf in the (bane of an elongated trochoid.
Ofthislaftwe can demonftrate the neceflity, becaufe
the cafe is fimple. In the wave, the inveftigation is
next to impoftible •, but we fee the faft. We may
therefore prefume it in air. And accordingly We know
that any noife, however abrupt and jarring, near at
hand, is fmooth at a diftance. Nothing is mote rough
/and harfti than the feream of a heron ; but at halt a
mile’s diftance it is foft. The ruffle of a drum is alfo
fmooth at a diftance. k
Fig 90. fhows the fucceftive fituations of the particles
of a row. Each line of the figure {hows the fame parti¬
cles marked with the fame letters } the firft particle a
being fuppofed to be removed fucceffively from its qui-
efeent fituation and back to it again. The maru X is
put on that part of each line where the agitated particles
are at their natural diftances, and the air is of the natu¬
ral denfity. The mark 1 is put where the air is molt of
all compreffed, and : where it is moft of all dilated j
the curve line drawn through the lowed; line of the^ fi-
gure is intended to reprefent the denfity jn every point,
by drawing ordinates to it from the ftraigbt line . the
A T I c S, 73t
ordinates below the line indicate a rarity, and thofe MnUtinn
above the line a denfity, greater than common.   
It appears that when a has come back to its natural
fituation, the part of greateft denfity is between the
particles i and k, and the greateft rarity between
We have only to add, that the velocity of this pro¬
pagation depends on the elafticity and denfity of tne
fluid. If thefe vary in the fame proportion, that is, it
the fluid has its elafticity proportional to its denfity, the
velocity will remain the fame. If the elafticity or den¬
fity alone be changed, the velocity of the undulations
will change in the direct fubduplicate ratio ot the eiaiu-
city and the inverfe fubduplicate ratio of the denfity j
for fiiould the elafticity be quadrupled, the quantity ot
motion produced by it in any given time will be qua-
drupled. This will be the cafe if the velocity be
doubled; for there would then be douole the number o,.
particles doubly agitated. Should the denfity be qua¬
drupled, the elafticity remaining the fame, the quantity
of motion muft remain the fame. This will be the cale
if the velocity be reduced to one half •, for this will pro¬
pagate half the agitation to half the diftance, which
will communicate it to twice , the number of particles,
and the quantity of motion will remain the fame. I be
fame may be faid of other proportions, and theretorc
in the fuc-
cefiive
pulfes af-
fumes a
cycloidal
hna.
Plate
•ccccxxxii.
fig. 90.
v=vS. Therefore a change in the barometer will
Vd* . , ,
not affed the velocity of thfe undulations m air 5 but they
will be accelerated by heat, which diminiihes its denfity,
or increafes its elafticity. The velocity of the pukes m
inflammable air muft be at leaft thrice as great, becaule
its denfity is but one-tenth of that of air when the elaia-
city of both are the fame. . ranhe'r
Let us now attend a little to the propagation of aeml ^^rther^
pulfes as they really happen for this hypolhefis ot a tioa of ae^
fingle row of particles is nowhere to be obferved. ^ai pulfes
Suppofe a fphere A, fig. 91- with condenfed air, as they
and that the veflfel which contains it is fuddenly anmhi-r^Ly oc
lated. The air muft expand to its natural dimenfions,
fuppofe BCD. But it cannot do this without prefling
afide the furrounding air. We have feen that in any
finale row of particles this cannot be at once diftuled to
a diftance, but muft produce a condenfation in the air
adjoining which will be gradually propagated to a di¬
ftance. Therefore this fphere BCD of the common
denfity will form round it a {hell, bounded by EFG, ot
condenfed air. Suppofe that at this inftant the inner
air BCD becomes folid. The. {hell of coudenfed air can
expand only outwards. Let it expand till it is ^of the
common denfity, occupying the {hell HIK. This ex-
panfion, in like manner, muft produce a {hell ot con¬
denfed air without it : at this inftant let HIK become
folid. The furrounding {hell of condenfed air can ex¬
pand only outward, condenfing another {hell without it.
It is plain that this muft go on continually, and the cen¬
tral agitation will be gradually propagated to a diftance
in all directions. But, in this procefs, it is not the fame
numerical particles that go to a diftance. 1 hofe of the
original fphere go no further than BCD, tiioie ot the
next {hall go no further than HIK, &c. Farther, the
expanfion outwards of any particle will be more mode¬
rate as the diffufion advances j for the whole motion of
4 Z 2 each
732
Undulation each cannot exceed the original quantity of mo-
, '!t ' , tion ; and the number of particles in each fucceilive {hell
increafes as the furface, that is, as the fquare of the di-
ftance from the centre ; therefore the agitation of the
particles will decreafe in the fame ratio, or will be in
the inverfe duplicate ratio of the diftance from the cen¬
tre. Each fucceffive (hell, therefore, contains the lame
quantity of motion, and the fucceffive agitations of the
particles of any row out from the centre will not be
equal to the original agitation, as happens in the folitary
row. But this does not afFsfl the velocity of the pro¬
pagation, becaufe all agitations are propagated equally
fait.
We fuppofed the air A to become folid as foon as it
acquired the common denfity 5 but this was to facilitate
the conception of the diffufion. It does not Hop at this
bulk } for while it was denier it had a tendency to ex¬
pand. Therefore each particle has attained this diilance
with an accelerated motion. It will, therefore, conti¬
nue this motion like a pendulum that has paifed the per¬
pendicular,^ till it is brought to reft by the air without
it; and it is now rarer than common air, and collapfcs
again by the greater elafticity of the air without it.
Ihis outward air, therefore, in regaining its natural
denfity, mutt expand both ways. It expands towards
the centre, following the collapfing of the air within it 5
and it expands outwards, condenfing the air beyond it.
By expanding inwards, it will again cohdenfe the air
within it, and this will again expand ; a fimilar motion
happens in all the outward {hells ; and thus there is pro¬
pagated a fucceffion of condtnfed and rarefied {hells of
air, which gradually fwell to the greateft diftance.
It may be demonftrated, that when the central air
has for the fecond time acquired the natural denfity, it
will be at reft, and be difturbed no more ; and that
this will happen to all the {hells in fucceffion. But the
demonftration is much too intricate for this place ; we
,.5 muft be contented with pointing out a fa cl perfectly
Application analogods. When we drop a fmall pebble into water,
of the fart we fee it produce a feries of circular waves, which go
a* ebb!eing a*onS ^le ^urface °f hnoolh water to a great diftance,
into water. becoming more :ir>d more gentle as they recede from the
centre ; and the middle, where the agitation w^as firft
produced, remains perfectly fmooth, and this fmooth-
nefs extends continually j that is, each wave when
brought to a level remains at reft. Now thefe waves
are produced and propagated by the depreffion and ele¬
vation made at the centre. The elevation tends to dif-
fufe itfelf; and the force with which each particle of
water is aftuated is a force adling dire&ly up and down,
and is proportional to the elevation or depreffion of the
particle. T his hydroftatical preffure operates precifely
in the fame way as the condenfation and rarefaftion of
the air ; and the mathematical inveftigation of the pro¬
pagation of the circular undulations on fmooth water
is fimilar in every ftep to that of the propagation of the
fpherical waves in ftill air. For this we appeal to New¬
ton’s Principle), or to Euler’s Opufcula, where he gives a
very beautiful inveftigation of the velocity of the aerial
pulfes ; and to fome memoirs of de la Grange in the
• colleftions of the academies of Berlin and Turin. Thefe
two laft authors have made the inveftigation as fimple
as feems poflible, and have freed it from every objedfion
which can be ftated againft the geometrical one of their
greater teacher Newton.
PNEUMATICS.
Having faid this much on the milarity between theUl d:'iatioh
waves on water and the aerial und lations, we {hall have °f Air.
recourle to them, as affording us a very lenfible object v——'
to reprefent many affe&ions of the other which it r. 337
would be extremely difficult to explain. We neither fee 0f vya'^W
noi feel tne aeiial undulations j and they behoved, there-^re ufeful
lore, to be deferibed very abftrabtedly and imperfectly. t7)r exp’ain-
In die watery wave there is no permanent pr0grtffiveing thofe
motion of the water from the centre. Throw a {mail bit°f alf'
01 cork on the furface, and it will be obferved to popple
up and down without the leaft motion outwards, in like
manner, the particles of air are only agitated a very
hale outwards ana inwards 5 which motion is commu¬
nicated to the particles beyond them, while they them-
felyes come to reft, unlefs agitated afreffi 5 and this agi¬
tation of the particles is inconceivably fmall. Even the
explofion of a cannon at no great diftance will' but
gently agitate a feather, giving it a fingle impulfe out¬
wards, and immediately after another inwards or to¬
wards the cannon. W hen a harpfichord wire is forcibly
twanged at a few feet diftance, the agitation of the
air is next to infenfible. It is not, however, nothing j
aiivi it differs from that m a watery wave by being venlly
outwards and inwards. In confequence of this, when
the condenfed fliell reaches an elaitic body, it impels
it {lightly. If its elafticity be fuch as to make it ac¬
quire the oppofite ffiape at the inftant that the next
agitation and condenfed fhell of air touches it, its agi¬
tation will be doubled, and a third agitation will increafe
it, and fo on, till it acqure the agitation competent,
to that of the fhell of air which reaches it, and it is
thrown into fcnjible vibration, and gives a found ex¬
tremely faint indeed, becaufe the agitation which it ac-
qunes is that correfponding to a fhell of air confider-
ably removed from the original firing. Hence it hap¬
pens that a mufical cnord, pipe, or bell, will caufe
another to refound, whofe vibrations are ifoehronous
v.ith its own j or if the vibrations of the one coin¬
cides with every fecond, or third, or fourth, &c. of the
other 5 juft as we can put a very heavy pendulum into
fenfible motion by giving it a gentle puff with the
breath at every vibration, or at every fecond, third, or
fourth, &c. A drum ftruck in the neighbourhood of
another drum will agitate it very fenjibly; for here the
ftroke depreffes a very confiderable furface, and pro¬
duces an agitation of a confiderable mafs of air : it will
even agitate the furface of ftagnant water. The explo¬
fion of a cannon will even break a neighbouring win¬
dow. The fhell of condenfed air which comes againft
the glafs has a great furface and a great agitation: the
beft lecurity in this cafe is to throw up the fafti 5 this
admits the condenfed air into the room, which a6ts on
the inlide of the window, balancing part of the external
impulfe.
It is demonftrated in every elementary treatife of na-Forwaves
tural philofophy, that when a wave on water meets any a‘r an(i
plane obftacle, it is refle&ed by it from a centre equal-ofwater
ly removed behind the obftacle 5 that waves radiating
from the focus of a parabola are renected in waves per-very funi/
pendicular to its axis; that waves radiating from one *;u‘-
focus of an ellipfe are made to converge to the other
locus, &c. &c. All this may be affirmed of the aerial
undulations; that when part of a wave gets through a
hole in the obftacle, it becomes the centre of a new fe¬
ries of waves 5 that waves bend round the extremities
of
P N E U M A X I C S.
733-
Undu'atisn 0f an obftaclc : all’ this happens in the aerial undula-
ot \ir. . tions. - And laf-tly, .that when the fur face o£ water is
v : thrown into regular undulations by one agitation, ano¬
ther agitation in another , place will produce other re¬
gular waves, which will crpfs the former without di-
(lurbtng them in the fmallelt degree. The fame thing
happens in air j and experiments may he made on wa¬
ter which will ij lull rate .hr the moil perfect manner
many other aftediiqns of. the aerial pulfes, which we
fhould otherwife conceive very imperfectly. We would
recommend to our curious readers to make fome of
thefe experiments in a large veffel of milk. Take a
long and narrow plate of lead, which, when fet on the
bottom of the veffel will reach above the furface of the
milk j bend this plate into a parabola, elliptical or other
curve. Make the undulations by dropping milk on the
focus from a frnall pipe; which will caufe the agita¬
tions to fucceed with rapidity, and then all that wre have
faid will be moft .diftinCUy feen, and the experiment
will be very amufing and inllruCHve, efpecially to the
^ mufical reader.
Caution to / We would now requeft all who make or read explaT
die fup- nations.of natural phen'omena by means of vibrations of
p. i ters of _ others, animal {'pints, nervous fluids, &c. to fix their
attention on the nature of the agitation in one of thefe
’ undulations.. Let him confider whether this can pro¬
duce the phenomenon, acting as any matter muft aCl, by
impulfe or by preiTure. If he fees that it can produce
the phenomenon, he will be able to point out the very
motion it will produce, both in quantity and direction,
in the fame manner as Sir Ifaac Newton has pointed
out all the irregularities of the moon’s motion produ¬
ced by the diflurbing force of the fun. If he cannot
do this, he fails in giving the firfl evidence of a me¬
chanical explanation by the aCtion of an elafiic vibrating
fluid. Let him then try to point out fome palpable con¬
nexion between the general phenomena of elaflic undu¬
lations and the phenomenon in queflion 5 this would fliow
an accompaniment to have at leafl fome probability. It
is thus only we learn that the undulations of air produce
found : we cannot tell how they affeX the mechanifm
of the ear ; but we fee that the phenomena of found al¬
ways accompany them, and that certain modifications
of the one are regularly accompanied by certain modi¬
fications of the other. If we cannot do this neither, we
have derived neither explanation nor illuftration from
the elaftic fluid. And laflly, let him remember that
even if he fliould be able to fhow the competency of
this fluid to the produXion of the phenomenon, the
• whole is Hill an hypothefis, becaufe we do not know
that fuch a fluid exiits.
The*folly We will venture to fay, that whoever will proceed in
of appeal- this prudent manner will foon fee the futility of moft:
ing to fich of the explanations of this kind which have been given,
fhbft °nces are un^t *or any ^ut confummate mathematicians ;
r ■" for they alone really underftand the mechanifm of . ae¬
rial undulations, and even they fpeak of them with he-
fitation as a thing but imperfeXly underftood. But
even the unlearned in this fcience can fee the incom¬
patibility of the hypothefes with many things which
they are brought to explain. To take an inftance of
the conveyance of fenfation along the nerves; an elaftic
fluid is fiippofed to occupy them, and the undula¬
tions of this fluid are thought to be propagated along
the nerves. Let us juft think a little how the undula¬
tions would be conveyed along-the furface of a canal Air’s
which was completely filled up with reeds and bulrufties, Preflure. .
or let us make the experiment on fuch a canal: we may v
reft affured that the undulations in the one cafe will
referable thofe in the other ; and we may fee that in the
canal there wall be no regular or fenfible propagation of
the waves.
Let thefe obfervations have their influence, along
with others which we have made on other occafions, to
wean our readers from this falhionable pronenefs to in¬
troduce invifible fluids and unknown vibrations into our
phyfical difcuflions. They have done immenfe, and we
fear irreparable, mifcluef in fcience ; and there is but one
phenomenon that has ever received any explanation by
their means.
. This may fuffice for a loofe and popular account of.
aerial undulations ; and with it we conclude our account
of the motion, impulfe, and refiftance of air.
We {hall now explain a number of natural appear¬
ances, depending on its preflure and elafticity, appear¬
ances not fufficiently general, or too complicated for the
purpofes of argument, while we were employed in the
inveftigation of thefe properties, but too important to be
paffed over in iilence. r
It is owing to the preffure of the atmofphere that The air’s
two furfaces which accurately fit each other cohere with preffure 00
fuch force. This is a faX familiarly known to the glafs- cafiolls ^
grinders, poliihers of marble, &c. A large lenfe or fpe- °f
calum, ground on its topi till it becomes very fmooth, faces accU.
requires more than any man’s ftrength to feparate it di-rately fit-
reXly from the tool. If the furface is only a fquare ting each
inch, it will require 15 pounds to feparate them perpen- ot^er ’
dicularly, though a very moderate force will make them
Aide along each other. But this cohefion is not ob-
ferved unlefs the furfaces are wetted or fmeared with
oil or greafe ; otherwife the air gets between them, and
they feparate without any trouble. That this cohefion
is owing to the atmofpheric preflure, is evident from the
eafe with which the plates may be feparated in an ex^
haufted receiver.
To the fame caufe xve muft afcribe the very ftrongandthe ad-
adhefion of fnails, periwinkles, limpets, and other uni- hefion of
valve {hells, to the rocks. The animal forms the rim fnafl5. &-c«
of its ftiell, fo as to fit the fhape of the rock to which ftt0 r0^5*
intends to cling. It then fills its {hell (if not already
filled by its own body) with water. In this condition
it is evident that we muft aX with a force equal to 15
pounds for every fquare inch of touching furface be¬
fore we can detach it. This may be illuftrated by fill,
ing a drinking glafs to the brim with water j and having
covered it with a piece of thin wet leather, whelm it on
a table, and then try to pull it ftraight- up ; it will re¬
quire a confiderable force. But if we expofe a fnail ad¬
hering to a ftone in the exhaufted receiver, we {hall fee
it drop off by its own weight. In the fame manner
do the remora, the polypus, the lamprey, and many
other animals, adhere with fuch firmnefs. Boys fre¬
quently amufe themfelves by pulling out large ftones
from the pavement by means of a circle of ftiff wetted
leather, faftened to a firing. It is owing to the fame
caufe that the bivalve {hell fifties keep themfelves fo
firmly {hut. We think the mufcular force of an oyfter
prodigious, becaufe it requires fuch force to open it; but
if we grind off a bit of the convex {hell, fo as to make a
hole in it, though without hurting the fifli in the fmall-
* eft .
734
Effects of
Air’s pref-
fure.
3-13
Other ef-
fedts of
the air’s
preffure.
PNEUMATICS.
Plate
ccccxxxr.
% 74*
344
Why trofts
iiiftantly
occafion a
fcarcity of
water.
345
The necef-
fity of com¬
mon air to
anima life.;
eft degree, it opens tvilli great eafe, as it does alfo in
vacuo.
The preflure of the air, operating in this way, con¬
tributes much to the cohelion of bodies, where we do
not fufpeft its influence. The tenacity of our mortars
and cements would frequently be ineffectual without this
afliftance.
It is owing to the preflure of the atmofphere that a
calk will not run by the cock unlefs a hole be opened in
tome other part of the calk. If the calk is not quite
full, fome liquor indeed will run out, but it will flop as
foon as the diminilhed elafticity of the air above the li¬
quor is in equilibrio (together with the liquor) with the
atmofpheric preflure. In like manner, a teapot mull
have a fmall hole in its lid to enfure its pouring out the
tea. If indeed the hole in the calk is of large dimen-
fions, it will run without any other hole, becaufe air
will get in at the upper fide of the hole while the liquor
runs out by the low?er part of it.
On the fame principle depends the performance of an
inftrument ufed by the fpirit dealers for taking out a
fample of their fpirits. It confifts of a long tinplate
tube AB (fig. 74.), open a-top at A, and ending in a
fmall hole at B. The end B is dipped into the fpirits,
which riles into the tube j then the thumb is clapt on
the mouth A, and the whole is lifted out of the calk.
The Ipirit remains in it till the thumb be taken off j it
is then allowed to run into a glafs for examination.
It feems principally owing to the prefiure of the air
that frofts immediately occafion a fcantinefs of water in
our fountains and wells. This is erroneoufly accounted
for, by fuppofing that the water freezes in the bowels
of the earth. But this is a great miftake : the moll
intenfe froft of a Siberian winter would not freeze the
ground twm feet deep \ but a very moderate froft wall con-
folidate the whole furface of a country, and make it
impervious to the air •, efpecially if the froft; has been
preceded by rain, which has foaked the furface. When
this happens, the water which wTas filtering through the
ground is all arrefted and kept fufpended in its capil¬
lary tubes by the preffure of the air, in the very fame
manner as the fpirits are kept fufpended in the inftru¬
ment juft now defcribed by the thumb’s (hutting the
hole A. A thaw melts the fuperficial ice, and allows
the water to run in the fame manner as the fpirits run
when the thumb is removed.
Common air is neceflary for fupporting the lives of
moll animals. If a fmall animal, fuch as a moufe or
bird, be put under the receiver of an air-pump, and the
air be exhaufted, the animal w ill quickly be thrown into
convulfions and fall down dead •, if the air be immedi¬
ately readmitted, the animal will fometimes revive, efpe¬
cially if the rarefaCtion has been brilkly made, and has
not been very great. We do not know that any breath¬
ing animal can bear the air to be reduced to one-fourth
of its ordinary denfity, nor even one third } nor have wre
good evidence that an animal wall ever recover if the
rarefaCtion is pulhed very far, although continued for a
very ftiort time.
But the mere prefence of the air is by no means fuf-
ficient for preferving the lire of the animal; for it is
found, that an animal (hut up in a veffel of air cannot
live in it for any length of time. If a man be (hut up
in a box, containing a wine hogfhead of air, he cannot
live in it much above an hour, and long before this he
4
will find his breathing very unfatisfaCtory and uneafy. Effefh of
A gallon of air will fupport him about a minute. A ^ir’s Prel*
box EF (fig. 75.) may l 4 made, having a pipe AB in-, ,
ferted into its top, and fitted wdth a very light valve atpjg, ^
B, opening upwards. This pipe fends off a lateral
branch a D </C, wdiich enters the box at the bottom,
and is alfo fitted with a light valve at C opening up¬
wards. If a perfon breathe through the pipe, keeping
his noftrils fhut, it is evident that the air which he ex¬
pires wall not enter the box by the hole B, nor return
through the pipe CD d; and by this contrivance he
will gradually employ the whole air of the box. With
this apparatus experiments can be made without any
rilk or inconveniency, and the quantity of air neceflary
for a given time of eafy breathing may be accurately
afcertained.
How the air of our atmofphere produces this effeCh,
is a queftion which does not belong to mechanical phi-
lofophy to inveftigate or determine. We can, howT-
ever, affirm, that it is neither the preflfure nor the elafti¬
city of the air which is immediately concerned in main¬
taining the animal functions. We know that wre can
live and breathe with perfeCt freedom on the tops of the
higheft mountains. The valley of Quito in Peru, and
the country round Gondar in Abyffinia, are fo far eleva¬
ted above the furface of the ocean, that the preflure and
the elafticity of the air are one-third lefs than in the low
countries; yet thefe are populous and healthy places.
And, on the other hand, wre know, that when an ani¬
mal has breathed in any quantity of air for a certain
time without renewal, it will not only be fuffocated, but
another animal put into this air will die immediately ;
and we do not find either the preflfure or elafticity of
the air remarkably diminiffied : it is indeed diminiftied,
but by a very fmall quantity. Reftoring the former
preflure and elafticity has not the fmalleft tendency to
prevent the death of the animal : for an animal will live
no longer under a receiver that has its mouth inverted
on wrater, than in one fet upon the pump-plate covered
with leather. Now when the receiver is fet on wraterf
the preflure of the atmofphere ads completely on the
included air, and preferves it in the fame ftate of elafti-
Cltyr' • • • . 346
In ftiort, it is known that the air which has already The nature
ferved to maintain the animal funCHons has its chemical0^a‘r .
and alimentary properties completely changed, and is no u ^
longer fit for this purpofe. So much of any mafs of air^m-q11^
as has really been thus employed is changed into wdratfun&ions is
is called Jixed air by Dr Black, or carbonic acid by the quite alter-
ehemifts of the Lavoifierian fchool. Any perfon mayec**
be convinced of this by breathing or blowing through a
pipe immerfed in lime water. Every expiration will
produce white clouds on the water, till ail the lime
which it contains is precipitated in the form of pure
chalk. In this cafe we know that the lime has combi¬
ned with the fixed air. ^
The celebrated Dr Stephen Hales made many ex-Hales’s ex¬
periments, wdth a view to clear the air from thePeriments
noxious vapour which he fuppofed to be emitted fromt0 reftore
lhedunss-. , r , S
He made ufe of the apparatus wffiich we have been &.c.
juft now mentioning ; and he put feveral diaphragms
Jf, jf, &c. of thin woollen fluff into the box, and moif-
tened them with various liquids. He found nothing fo
efficacious as a folution of potafli. We now under-
lland
Effects of
Air’s pref-
fur e.
348
How it
comes to
be changed
by breath¬
ing, and
the nature
of infpira-
tion, See.
P N E U M
ftand tliis perfe&Iy, If the folulion is not already fa-
turated with fixed air, it will take it up as fatl as it is
produced, and thus will purify the air: a folution of
cauflic alkali therefore will have this effe6t till it is ren¬
dered quite mild.
Thefe experiments have been repeated, and varied in
many circumftances, in order to afeertain whether this
fixed air was really emitted by the lungs, or whether
the infpired air was in part changed into fixed aw by
its combination with fome other lubftance. I his is a
queftion -which comes properly in our way, and which
the doctrines of pneumatics enable us to anfwer. If
the fixed air be emitted in fubftance from the lungs, it
does not appear how a renewal of the air into which it
is emitted is neceffary : for this does not hinder the
fubfequent emiflion; and the bulk of the air would be
increafed by breathing in it, viz. by the bulk of all the
fixed air emitted ; but, on the contrary, it is a little di-
minithed. We mult therefore adopt the other opinion j
and the difeoveries in modern chemiftry enable us to
give a pretty accurate account of the whole procefs.
Fixed air is acknowledged to be a compound, of which
one ingredient is found to conftitute about three-eighths
of the whole atmofpheric fluid 5 we mean vital air or the
oxygen of Lavoifler. When this is combined with phlo-
giflon, according to the doftrine of Stahl, or with char¬
coal, according to Lavoifier, the refult is fixed air or
carbonic acid. The change therefore which breathing
makes on the air is the folution of this matter by vital
air *, and the ufe of air in breathing is the carrying off
this noxious principle in the way of folution. \\ hen
therefore the air is already fo far faturated as not to dif-
folve this fubftance as fail as it is fecreted, or muft be
fecreted in the lungs, the animal fuffers the pain of fuf-
focation, or is otherwife mortally affecled. Suffocation
is not the only confequence ; for we can remain for a
number of feconds without breathing, and then we be¬
gin to feel the true pain of fuffocation *, but thofe who
have been inftantaneoufly ftruck down by an infpiration
of fixed air, and afterwards recovered to life, complain¬
ed of no fuch pain, and feemed to have fuffered chiefly
by a nervous affe£Hon. It is faid (but we will not
vouch for the truth of it), that a perfon may fafely take
a full infpiration of fixed air, if the paffagesof the nofe be
{hut; and that unlefs thefe nerves are ftimulated by the
fixed air, it is not inftantaneoufly mortal. But thefe are
queftions out of our prefent line of inquiry. T-hey are
queftions of phyfiology, and are treated of in other places
of this work. See Anatomy and Physiology j fee
alfo Lungs and Respiration. Our bufinefs is to explain
in what manner the preffure and elafticity of the air,
combined with the ftrufture and mechanilm of the bo¬
dy, operate in producing this neceffary fecretion and re¬
moval of the matter difeharged from the lungs in the
a6I of breathing.
It is well afeertained, that the fecretion is made from
the mafs of blood during its paffage through the lungs.
The blood delivered into the lungs is of a dark blackifli
colour, and is there changed into a florid red. In
the lungs it is expofed to the aftion of the air in a pro-
digioully extended furface : for the lungs confift of an
inconceivable number of fmall veffels or bladders, com¬
municating with each other and with the windpipe.
Thefe are filled with air in every infpiration. Thefe
veffels are everywhere in contaft with minute blood-vef-
A T I C S. 735
fels. The blood does not in loio come into immediate rffefts of
contact with the air j and it would feem that it is only '
the thin ferous part of it which is afted on by the air
at the mouths of the veffels or pores, where it ftands by
capillary attra&ion. Dr Prieftley found, that venous
blood inclofed in thin bladders and other membranes
was rendered florid by keeping the bladders in contaft
with abundance of pure vital air. We know alfo, that
breath is moift or damp, and mujl have acquired this
moifture in the lungs. It is immaterial whether this
fecretion of water or lymph (as the anatomifts call it)
be furnifhed by mere exudation through. Ample pores,
or by a vafcular and organic fecretion \ in either cafe,
fome ingredient of the blood comes in contaift with air
in the lungs, and there unites with it. I his is farther
confirmed, by obferving, that all breathing animals are
warmer than the furrounding medium, and that by every
procefs in which fixed air is formed from vital air heat
is produced. Hence this lolution in air of fomething
from the blood has been afligned by many as the fource
of animal heat. We touch on thefe things in a very
tranfitory way in this place, only in order to prove that,
for the fupport of animal life, there muft be a very ex-
tenlive application of air to the blood, and that this is
made in the lungs.
The queftion before us in this place is, Flow is this
brought about by the weight and elafticity of the air ?
This is done in two ways ; by the adtion of the mufcles
of the ribs, and by the adlion of the diaphragm and oilier
mufcles of the abdomen. I he thorax or cheft is a great
cavity, completely filled by the lungs. I he fides of
this cavity are formed by the ribs. 1 hefe are crooked
or arched, and each is moveable round its two ends, one
of them being inferted into the vertebrae of the back,
and the other into the fternum or breaft-bone. The rib
turns in a manner refembling the handle of a drawer.
The infpedlion of fig. 76. will illuftrate this matter a Fig. 76.
little. Suppofe the curves a c e, b kf c /g, &c. to re-
prefent the ribs moveable round the extremities. Each
fucceeding rib is more bent than the one above it, and
this curvature is both in the vertical and horizontal di-
redlion. Suppofe each fo broad as to projedt a little
over its inferior like the tiles of a roof. It is evident,
that if we take the lower one by its middle, and draw
it out a little, moving it round the line «/>, it will bring
out the next dm h along with it. Alfo, becaufe the di-
ftance of the middle point 0 from the axis of motion np
is greater than the diftance of m from the axis dh, and
becaufe 0 will therefore deferibe a portion of a larger
circle than m does, the rib « will Aide up a little un¬
der the rib d m h, or the rib d m h will overlap n op -a.
little more than before ; the diftance 0 m will therefore
be diminifhed. The fame muft happen to all the fupe-
rior ribs’, but the change of diftance wall be lefs and lefs
as we go upwards. Now, inftead of this great breadth
of the ribs overlapping each other, fuppofe each inferior
rib connedled with the one above it by threads or fibres
fufceptible of contradlion at the will of man. The arti¬
culations e, a, of the firft or upper rib with the fpine and
flernum are fo broad and firm, that this rib can have
little or no motion round the line a e ; this rib therefore
is as a fixture for the ends of all the contrafting fibres :
therefore, whenever the fibres which conned! the fecond
rib with the firft rib contradl, the fecond muft rife a
little, and alfo go outward, and will carry the lower
ribs
P N E U M
Jiffi-As of ribs along with it j the third rib will rife ftill farther by
-Alljf1)ie1' the contraflion of the mufcles which connefl it with
•i-, the fecond, and fo on : and thus the whole ribs are raif-
ed and thrown outward (and a little forward, becaufe
the articulation of each with the fpine is confiderably
higher than that with the iternum), and the capacity of
the thorax is enlarged by the contraction of its mulcu-
lar covering. The diredlion of the mufcular fibres is
very oblique to the direction ol the circular motion
which it produces j from which circumftance it follows,
that a very minute contraction of the mufcles produces
, all the motion which is necelfary. This indeed is not
greatthe whole motion of the lowed ribs is lefs than
an inch in the mod violent infpiration, and the whole
contraction of the mufcles of the twelve ribs does not
exceed the eighth part of an inch, even fuppofing the
intercodal mulcles at right angles to the ribs j and be¬
ing oblique, the contraction is dill lefs (fee Eorelli,
Sabatier, Monro, &c.). It would feem, that the
intenfity of the contraCtive power of a mulcular fibre is
eafily obtained, but that the fpace through which it can
be exerted is very limited j for in mod cafes nature
places the mufcles in fituations of great mechanical dif-
advantage in this refpedt, in order to procure other con¬
veniences.
But this is not the whole effedt of the contraction of
the intercodal mufcles: fince the compound aftion of the
two fets of mufcles, which crofs each other from rib to
rib like the letter X, is nearly at right angles to the
rib, but is oblique to its plane, it tends to pudi the ribs
clofer on their articulations, and thus to prefs out the
two pillars on which they are articulated. Thus, fup-
Eig-77* P°hng (fig- 77-) to reprefent the feftion of one of
the vertebrae of the fpine, and c </ a fedtion of the der-
num, and a b c,fed, two oppofite ribs, with a lax thread
b e connecting them. If this thread be pulled upwards
hy the middle g till it is tight, it will tend to pull the
points b and e nearer to each other, and to prefs the
vertebra a f and the dernum c d outwards. The fpine
being the chief pillar of the body, may be confidered
as immoveable in the prefent indance. The dernum is
fufficiently fufceptible of motion for the prefent purpofe.
It remains almod fixed a-top at its articulation with the
fird rib, but it gradually yields below 5 and thus the
capacity of the thorax is enlarged in this direftion alfo.
The whole enlargement of the diameters of the thorax
during infpiration is very fmall, not exceeding the fif¬
tieth part of an inch in ordinary cafes. This is eafily
« calculated. Its quiefeent capacity is about two cubic
feet, and rve never draw in more than 15 inches. Two
fpheres, one of which holds 2 cubic feet and the other
2 feet and 15 inches, will not differ in diameter above
the fiftieth part of an inch.
The other method of enlarging the capacity of the
thorax is very different. It is feparated from the ab¬
domen by a drong mufcular partition called the dia¬
phragm, which is attached to firm parts all around.
In its quiefeent or relaxed date it is confiderably convex
upwards, that is, towards the thorax, rifing up into its
cavity like the bottom of an ordinary quart bottle, only
not fo regular in its diape. Many of its fibres tend
from its middle to the circumference, where they are in-
ferted into firm parts of the body. Now fuppofe thefe
fibres to contraft. This mud draw down its middle,
A TIC S.
or make it flatter than before, and thus enlarge the ca- Effetds of
pacity of the thorax. Au v pret-
Phyfiologifts are not well agreed as to the fliare which ,
each of thefe actions has in the operation of enlarging
the thorax. Many refufe all fhare of it to the intercodal
mufcles, and fay that it is performed by the diaphragm
alone. But the fail; is, that the ribs are really oblerved
to rife even while the perfon is aileep j and this cannot
poflibly be produced by the diaphragm, as thefe anato-
mifis affert. Such an opinion fliows either ignorance
or neglect of the laws of pneumatics. If the capacity
of the thorax were enlarged only by drawing down the
diaphragm, the preffure of the air would comprefs the
ribs, and make them defeend. And the limple laws
of mechanics make it as evident as any propbfition in
geometry, that the contrabtion of the intercodal mufcles
mujl produce an elevation of the ribs and enlargement
of the thorax ; and it is one of the mod beautiful con¬
trivances of nature. It depends much cn the will of
the animal what fliare each of thefe a ft ions fliall have.
In general, the greateft part is done by the diaphragm;
and any perfon can breathe in fuch a manner that his
rib fliall remain motionlefs •, and, on the contrary, he
can breathe almofi: entirely by railing his cheft. In the
fird method of breathing, the belly rifes during infpira¬
tion, becaufe the contraftion of the diaphragm com-
preffes the upper part of the bowels, and therefore
fqueezes them outwards ; fo that an ignorant perfon
would be apt to think that the breathing was performed
by the belly, and that the belly is inflated with the air.
The drait lacing of the women impedes the motion of
the ribs, and changes' the natural habit of breathing, or
brings on an unnatural habit. When the mind is de-
prefied, it is obferved that the breathing is more per¬
formed by the mufcles of the thorax j and a deep figh is
always made in this way.
Thefe obfervations on the manner in which the capa¬
city of the died can be enlarged were neceffary, before
we can acquire a jud notion of the wray in which the
mechanical properties of air operate in applying it to
the mafs of blood during its paffage through the lungs.
Suppofe the thorax quite empty, and communicating
with the external air by means of the trachea or wind¬
pipe, it would then referable a pair ofbellows. Railing
the boards correfponds to the railing of the ribs ; and
we might imitate the aftion of the diaphragm by for¬
cibly pulling outwards the folded leather which unites
them. Thus their capacity is enlarged, and the air
ruflies in at the nozzle by its weight in the fame manner
as water would do. The thorax differs from bellows
only in this refpeft, that it is filled by the lungs, which
is a vad collection of little bladders, like the holes in a
piece of fermented bread, all communicating with the
trachea, and many of them with each other. When
the ched is enlarged, the air rulhes into them all in the
fame manner as into the fingle cavity of an empty7 tho¬
rax. It cannot be faid with propriety that they are in¬
flated : all that is done is the allowing the air to come
in. At the fame time, as their membranous covering
mud have fome thicknefs, however fmall, and fome
elafiicity, it is not unlikely that, when comprtffed by
expiration, they tend a little to recover their former
drape, and thus aid the voluntary aftion of the mufcles.
It is in this manner that a fmall bladder of caoutchouc
fwells
2
Effe&s of fwells again after coinpreflion, and fills itfelf with air
Air’s pref- or water. But this cannot happen except in the moil
fure‘ minute veficles: thofe of fenfible bulk have not da-
Wj y fticity enough for this purpofe. The lungs of birds,
however, have fome very large bladders, which have a
very confiderable elailicity, and recover their fhape and
fize with great force after compreffion, and thus fill
themfelves with air. d. he refpiration of thefe animals
is confiderably different from that of land animals, and
their mufcles a£l chiefly in expiration. _ This will be
explained by and by as a curious variety in the pneuma¬
tic inftrument.
This account of the manner in which the lungs are
filled with air does not feem agreeable to the notions
349 , yv£ entertain of it. We feem to fuck in the air ^ but al-
thoug}1 it be true that we aft, and exert force, in order
our own to get air into our lungs, it is not by our aftion, but by
adtion, but -external preffure, that it does come in. If we apply
by external our mouth to the top of a bottle filled with water, we
preffure. fmd that no draught, as we call it, of our cheft will
fuck in any of the water j but if we fuck in the very
fame manner at the end of a pipe immerfed in water, it
follows immediately. Our intereft in the thing makes
us conned in imagination our own action with the
effed, without thinking on the many fteps which may
intervene in the train of natural operations *, and we
confider the adion as the immediate caufe of the air’s
reception into the lungs. It is as if we opened the
door, and took in by the hand a perfon who w-as really
pufhed in by the crowd without. If an incifion be made
into the fide of the thorax, fo that the air can get in by
that way, when the animal ads in the ufual manner, the
air will really come in by this hole, and fill the fpace
between the lungs and the thorax; but no air is fucked
into the lungs by this procefs, and the animal is as com¬
pletely fuffocated as if the windpipe were fhut up. And,
on the other hand, if a hole be made into the lungs
without communicating with the thorax, the animal will
breathe through this hole, though the windpipe be flop¬
ped. This is fuccefsfully performed in cafes of patients
whofe trachea is (hut up by accident or by inflammation •,
only it is neceffary that this perforation be made into a
part of the lungs where it may meet with fome of the
great pulmonary paffages : for if made into fome remote
part of a lobe, the air cannot find its way into the reft
of the lungs through fuch narrow paffages, obftruded too
by blood, &c. . .
We have now explained, on pneumatical principles,
expiration, the procefs of inflation. The expiration is chiefly
performed by the natural tone of the parts. In the ad
of infpiration the ribs were raifed and drawn outwards
m oppofition to the elafticity of the folids themfelves ,
for although the ribs are articulated at their extremities,
the articulations are by no means fuch as to give a free
and eafy motion like the joints of the limbs. This is
particularly the cafe in tlie articulations with the fter-
num, which are by no means fitted for motion. It would
feem that the motion really produced here is chiefly
by the yielding of the cartilaginous parts and the bend¬
ing of the rib ; when therefore the mufcles which pro¬
duced this effed are allowed to relax, the ribs again
collapfe. Perhaps this is aflifted a little by the adion
of the long mufcles which come down acrofs the ribs
without being inferted into them. I hefe may draw them
Vol. XVI. Part II.
PNEUMATICS. 737
together a little, as we comprefs a loofe bundle by a
35°
Nature of
firing. fure
In like manner, when the diaphragm was drawn down,  
it compreffed the abdomen in oppofition to the elafticity
of all the vifeera contained in it, and to the elafticity and
tone of the teguments and mufcles which furround it.
When therefore the diaphragm is relaxed, thefe parts
pufti it up again into its natural fituation, and in doing
this expel the air from the lungs. _
If this be a juft account of the matter, expiration ^ requires
fliould be performed without any effort. This accord-no effort,
ingly is the cafe. We feel that, after having made an
ordinary eafy infpiration, it requires the continuance of
the effort to keep the thorax in this enlarged Hate, and
that all that is neceffary for expiration is to ceafe to a£l.
No perfon feels any difficulty in emptying the. lungs j
but weak people often feel a difficulty of infpiration, and
compare it to the feeling of a wTeight on their, breait j
and expiration is the laft motion of the thorax in a dy¬
ing perfon. _
But nature has alfo given us a mechanifm by which
we can expire, namely, the abdominal mufcles j and
when we have finithed an ordinary and eafy expiration,,
we can ftill expel a confiderable bulk of air (nearly hall
of the contents of the lungs) by contra&ing the abdo¬
minal mufcles. Thefe, by compreffing the body, force
up its moveable contents againft the diaphragm, and
caufe it to rife further into the thorax, afting in the fame
manner as when we expel the faeces per anum. . When
a perfon breathes out as much air as he can in this man¬
ner, he may obferve that his ribs do not collapfe during
the whole operation. < 352
There feems then to be a certain natural unconftrain- a certain
ed ftate of the veficles of the lungs, and a certain quan- quantity of
tity of air neceffary for keeping them of this fize. It is n^'
probable that this ftate of the lungs gives the freeft mo- theylunRS ^
tion to the blood. Were they more compreffed., the0fa natural
blood veffels would be compreffed by the adjoining fize.
veficles •, were they more lax, the veffels would be more
crooked, and by this means obftrudled. The . frequent
infpirations gradually change this air by mixing freffi
air with it, and, at every expiration carrying off fome
of it. In catarrhs and inflammations, efpecially when
attended with fuppuration, the fmall paffages into the
remote veffels are obftru&ed, and thus the renewal of
air in them will be prevented. The painful feeling
which this occafions caufes us to expel the air with vio¬
lence, (hutting the windpipe, till we have exerted ftrong-
ly with the abdominal mufcles, and made a ftrong com¬
preffion on the lower part of the thorax. We then open
the paffage fuddenly, and expel the air and obftrudling
matter by violent coughing. . . . .
We have faid, that birds exhibit a curious variety pr0cds of
in the procefs of breathing. The mufcles of their breathing
wings being fo very great, required a very extenfive
infertion, and this is one ufe of the great breaft-bone.
Another ufe of it is, to form a firm partition to hinder
the action of thefe mufcles from compreffing the thorax
in the ad of flying : therefore the form of their cheft
does not admit of alternate enlargement and contradion
to that degree as in land animals. Moreover, the
mufcles of their abdomen are alfo very fmall j and it
would feem that they are not fufheient for producing
the compreffion on the bowels which is neceffary for
c A carrying
738 _ P N E U M
EiT'^s of carrying on llie procefs of conco&ion and digeftion.
^ure' of aiding the lungs, they receive help from
l. - ...I them.
In an oflrich, the lungs confifl: of a fle(hy part A, A
Fig. 7S. ("%• 78-)» oompofed of veficles like thofe of land ani¬
mals, and, like theirs, ferving to expofe the blood to the
a cl ion of the air. Befides thefe, they have on each fide
four large bags If, C, I), E, each of which has an ori¬
fice G communicating with the trachea ; but the fecond,
C, has alfo an orifice H, by which it communicates with
another bag F fituated below the reft in the abdomen.
Now, v/hen the lungs are compreffed by the aft ion of
the diaphragm, the air in C is partly expelled by the tra¬
chea through the orifice G, and partly driven through
the orifice H into the bag F, which is then allowed to
receive it ; becaufe the fame action which compreffes the
lungs enlarges the abdomen. When the thorax is en¬
larged, the bag C is partly fupplied with frefh air through
the trachea, and partly from the bag F. As the lungs
of other animals referable a common bellows, the lungs
of birds referable the fmith’s bellows with a partition ;
and anatomifts have difcovered paflages from this part of
the lungs into their hollow bones and quills. We do
not know all the ules of this contrivance ; and only can
obferve, that this alternate a&ion muft aflift the mufcles
of the abdomen in promoting the motion of the food
along the^ alimentary canal, &c. We can diftinaiy ob-
*erve in birds that their belly dilates when the cheft col-
lapfes, and v/ce verfa, contrary to what we fee in the
land animals. Another ufe of this double paffage may
be to produce a circulation of air in the lungs, by which
a compenfation is made for the fmaller furface of aflion
on the blood : for the number of fmall veficles, of equal
capacity with thefe large bags, gives a much more ex-
tenfive furface.
If we try to raife mercury in a pipe by the a&ion of
the cheft alone, we cannot raife it above two or three
inches j and the attempt is both painful and hazardous.
It is painful chiefly in the breaft, and it provokes cough¬
ing. Probably the fluids ooze through the pores of the
veficles by the preffure of the furrounding parts.
On the other hand, we can by expiration fupport mer¬
cury auout five or fix inches high : but this alfo is very
painful, and apt to produce extravafation of blood. This
354 feems to be done entirely by the abdominal mufcles.
The opera- The operation properly termed SUCKING is totally dif-
fwckiirr ^rent from breathing, and refembles exceedingly the ac-
n°’ tion of a common pump. Suppofe a pipe held in the
mouth, and its lower end immerfed in water. We fill
the mouth wfith tbe tongue, bringing it forward, and
applying it clofely to the teeth and to the palate we
then draw it back, or bend it downwards (behind) from
tne palate, thus leaving a void. 1 he preflure of the
air on the cheeks immediately depreffes them, and ap¬
plies them clofe to the gums and teeth } and its preffure
on the water in the veffel caufes it to rife through the
pipe into the empty part of the mouth, which it quickly
fills. We then pufh forward the tip of the tongue, be¬
low the water, to the teeth, and apply it to them all
round, the water being above the tongue, which is kept
much depreffed. We then apply the tongue to the palate,
beginning at the tip, and gradually going backwards in
• his application. By this means the water is gradually
forced backward by an operation fimilar to that of the
gullet in fwallowing. "Ibis is done by contrafling the
A T I C S.
gullet above and relaxing It below, juft as we would Effects of
empty a gut of its contents by drawing our clofed hand Air’s pref-
along it. By this operation the mouth is again complete- fure-
ly occupied by the tongue, and we are ready for repeat- 'r"^
mg the operation. Thus the mouth and tongue refera¬
ble the barrel and pifton of a pump 5 and the application
of the tip of the tongue to the teeth performs the office
of the valve at the bottom of the barrel, preventing the
return of the water into the pipe. Although ufual, it
is not abfolutely neceffary, to withdraw the tip of the
tongue, making a void before the tongue. Sucking may
be performed by merely feparating the tongue gradually
from the palate, beginning at the root. If we withdraw
the tip of the tongue a very minute quantity, the water
gets in and flows back above the tongue.
I he action of the tongue in this operation is very
powerful ; fome perfons can raife mercury 25 inches :
but this ftrong exertion is very fatiguing, and the foft
parts are prodigioufly fwelled by it. It caufes the blood
to ooze plentifully through the pores of the tongue, fau¬
ces, and palate, in the fame manner as if a cupping-glafs
and fyringe were applied to them ; and, when the infide
of the mouth is excoriated or tender, as is frequent with
infants, even a very moderate exertion of this kind is ac¬
companied with extravafation of blood. When chil¬
dren fuck the nurfe’s breaft, the milk follows their exer¬
tion by the preffure of the air on the breaft 5 and a weak
child, or one that withholds its exertions on account of
pain from the above-mentioned caufe, may be aflifted
by a gentle preffure of tbe hand on the breaft : the in¬
fant pupn or nature, without any knowledue of pneuma¬
tics, frequently helps ilfelf by prefling its face to the yield¬
ing breaft.
In the whole of this operation the breathing is perfor¬
med through the noftrils 3 and it is a prodigious diftrefs
to^an infant when this paffage is obftrufted by mucus.
We beg to be forgiven for obferving by the way, that
this obftru&ion may be almoft certainly removed for a
little while, by rubbing the child’s nole with any liquid
of quick evaporation, or even with water.
The operation in drinking is not very different from and of 3
Inat in fucking : wre have indeed little occafion here to drinking:,
luck, but we muft do it a little. Fogs and fome other which w
animais cannot drink, but only lap the wTatcr into their )'er^
mouths with their tongue, and then fwallow it. The ar*
gallinaceous birds Item to drink very imperfedtly; they
feem merely to dip their head into the water up to the
eyes till their mouth is filled with water, and then hold¬
ing up the head, it gets into the gullet by its weight,
and is then fwallowed. The elephant drinks in a verv
complicated manner 3 be dips his trunk into tbe water,
and fills it by making a void in his mouth : this he does
in the contrary way to man. After having depreffed his
tongue, he begins tbe application of it to the palate at
the root, and by extending the application forward, he
expels the air by the mouth which came into it from the
trunk. The procefs here is not very unlike that of the
condenfing fyringe without a piflon valve, defcribed in
N° 58. in wFich the external air (correfponding here to
the air in the trunk) enters by the hole F in the fide,
and is expelled through the hole in the end of the bar¬
rel 3 by this operation the trunk is filled with water 3
then he lifts his trunk out of the wrater, and bringing it
to his mouth, pours the contents into it, and fwallows
it. On confidering this operation, it appears that, by
the
PNEUMATICS.
739
fure.
Effects of tlie fame procefs by which the air of the trunk is taken
An’s pref- into the mouth, the water could alio be tatcen in, to be
afterwards (wallowed : but we do not find, upon inquiry,
that this is done by the elephant } we have always ob-
ferved him to dtink in the manner now del'cribed. In
either way it is a double operation, and cannot be car¬
ried on any way but by alternately lucking and fwallow-
ing, and while one operation is going on the other is in¬
terrupted } whereas man can do both at the lame time.
Nature feems to delight in exhibiting to rational obfer-
yers her inexhauftible variety of refource •, for many in-
fe<as, which drink with a trunk, drink without interrup¬
tion : yet we do not call in queilion the truth or the
aphorifm, Natura maxim*Jimplex et femper Jibi confona,
nor doubt but that, if the whole of her purpofe were
feen, we (hould find that her procefs is the fimpleft pof-
fible : for Nature, or Nature’s God, is wife above our
wifeft thoughts, and fimplicity is certainly the choice of
wifdom : but alas ! it is generally but a (mail and the
moll obvious part of her purpoie that wre can oblerve or
appreciate. We feldom lee this iimphcity of nature Hat¬
ed to us, except by fome fyftem-maker, who has feund
a principle which lomehow tallies with a confiderable
variety of phenomena, and then cries out, Frujlra fit per
plura quod fieri potef per pauciora.
There is an operation fimilar to that of the elephant,
356
Mode of
keep n i up which many find a great difficulty in acquiring, viz- keep-
a continued jT1g Up a continued blaft with a blow-pipe. We would
!\ Wltha defire our chemical reader to attend minutely to the gra-
iow-pipc. aflion of his tongue in fucking, and he will find it
Inch as we have defended. Let him attend particularly
to the way in which the tip of the tongue performs the
office of a valve, preventing the return of the water into
the pipe: the fame pofition of the tongue would hinder
air from coming into the mouth. Next let him ooferve,
that, in fwallowing what water he has now got lodged
above his tongue, lie continues the tip of the tongue ap¬
plied to the teeth j now let him (hut his mouth, keeping
Ins lips firm together, the tip of the tongue at the teeth,
and the whole tongue forcibly kept at a diilance irom
the palate % bring up the tongue to the palate, and allow
the tip to feparate a little from the teeth, this will expel
the air ir'to the fpace between the fauces and cheeks, and
wu' blow up the cheeks a little : then, adling with the
tip of the tongue as a valve, hinder this air from_ getting
back, and deprelfing the tongue again, more air (from
the noftrils) will get into the mouth, which may be ex¬
pelled into the fpace without the teeth as before, and
the cheeks will be more inflated : continue this operation,
and the lips will no longer be able to retain it, and it
will ooze through as long as the operation is continued.
When this has oecome familiar and eafy, take the blow¬
pipe, and there will be no difficulty in maintaining a
blaft as uniform as a fmith’s bellows, breathing all
the while through the noftrils. The only difficulty
is the holding the pipe : this fatigues the lies 5 but it
may be removed by giving the pipe a convenient fhape,
a pretty flat oval, and wrapping it round with leather or
thread.
Another phenomenon depending on the principles al¬
ready eftablifhed, is the land and fea-breeze in the warm
countries.
We have feen that air expands exceedingly by heat *,
therefore heated air, being lighter than an equal, bulk
of cold air, mud rife in it. If we lay a hot done in the
357 r
Nature of
the land
and fea
breeze in
warm
eountnes.
funfhine in a room, we (hall obferve the fhadoW of the Me&s of
Hone furrounded with a fluttering ftiadow of difterent de- '
grecs of brightnefs, and that this flutter riles rapidly in —1
a column above the ftone. If we hold an extinguifhed
candle near the ftone, we fhall fee the (moke move to¬
wards the ftone, and then afeend from it. Now,
fuppofe an ifland receiving the firft rays of the fun in a
perfetftly calm morning ; the ground will fcon be warm¬
ed, and will warm the contiguous air. If the iftand be
mountainous, this effetl will be more remarkable 5 be-
caufe the inclined fides of tlie hills will receive the light
more direftly : the midland air will therefore be mod
warmed : the heated air will riie, and that in the middle
will rife failed \ and thus a current of air upwards will
begin, which muft be fupplied by air coming in from all
fides, to be heated and to rife in its turn ; and thus the
rxiw\\V(\v>fiea-bree%e is produced, and continues all day.
This current will frequently be reverfed during the
night, by the air cooling and gliding down the fides of
the hills, and we ftiall have the land-bree%e. , .3
It is owing to the fame caufe that we have a circula- Circulation
tion of air in mines which have the mouths of their’of air in
lhafts of unequal heights. The temperature under ground mine3*
is pretty conllant through the whole year, while that of
the atmofphere is extremely variable. Now, fuppofe a
mine having a long horizontal drift, communicating be¬
tween two pits or {hafts, and that one of thefe drafts ter¬
minates in a valley, while the other opens on the brow
of a hill perhaps 100 feet higher. Let us further fup¬
pofe it dimmer, and the air heated to 65°, while the
temperature of the earth is but 450 ; this lad will be
alio the temperature of the air in the lhafts and the
drift. Now, fince air expands nearly 24 parts in 10,000
by one degree of heat, we (hall have an odds of preffure
at the bottom of the two (hafts equal to nearly the 20th
part of the weight of a column of air 100 feet high
(100 feet being fuppofed the difference of the heights of
the (hafts). This will be about fix ounces on every fquare
foot of the fedlion of the draft. If this preflure could
be continued, it would produce a prodigious current of
air down the long (hafts, along the drift, and up the
(liort (haft. The weight of the air a cling through 100
feet would communicate to it the velocity of 80 feet
per fecond : divide this by 20, that is, by 4.5, and
we (hall have 18 feet per fecond for the velocity; this is
the velocity of what is called a brilk gale. This preffure
would be continued, if tbe warm air which enters the
long (haft were cooled and condenfed as fad as it comes
in j but this is not the cafe. It is however cooled and
condenfed, and a current is produced lufficient to make
an abundant circulation of air along the whole paffage j
and care is taken to difpofe the (hafts and condudl the
paffages in fuch a manner that no part of the mine is
out of the circle. When any new lateral drift is made,
the renewal of air at its extremity becomes more imper¬
fect as it advances: -and when it is carried a certain length,
the air ftagnales and becomes fuffocating, till either a
communication can be made with the reft of the mine,
or a (haft be made at the end of this drift.
As this current depends entirely on the difference of
temperature between the air below and that above, it
mud ceafe when this difference ceafes. Accordingly,
in the fpring and autumn, the miners complain much of
ftagnalion : but in dimmer they never want a current
from the deep pits to the (hallow, nor in the winter
5 A a a
740
Eifc&s of^
PNEUMATICS.
current from the {hallow pits to the deep ones. It
frecluent]y happens aifo. that in mineral countries the
359
The nature
of what is
called the
draughtin
chimneys.
chemical changes which are going on in different parts
of the earth make differences of temperature fuiFicient
to produce a fenf.ble current.
It is eafy to fee that the fame caufes muft produce
a current down our chimneys in fummer. The chim¬
ney is colder than the fummer air, and muft therefore
condenfe it, and it will come down and run out at the
doors and windows.
And tins naturally leads us to confider a very impor¬
tant effect of the expanfion and coniequent afcent of air
by heat, namely the drawing (as it is called) of chim¬
neys. The air which has contributed to the burning of
fuel muft be intenfely heated, and will rife in the atmo-
Iphere. This will alio be the cafe with much of the fur-
rounding air which has come very near the fire, although
not in contaft with it. If this heated air be made to rife
in a pipe, it will be kept together, and therefore will not
foon cool and collapfe: thus we fliall obtain a long column
of light air, which will rife with a force fo much the great¬
er as the column is longer or more heated. Therefore the
taller we make the chimney, or the hotter we make the
fire, the more rapid will be the current, or the draught
or finftion, as it is injudicioufly called, will be fo much
the greater. The afcenfional force is the difference be¬
tween the weight of the column of heated air in the fun¬
nel and a column of the furrounding atmofphere of equal
height. We increafe the draught, therefore, by increafing
the perpendicular height of the chimney. Its length in
a horizontal direifion gives no increafe, but, on the con¬
trary, diminifhes the draught by cooling the air before it
gets into the effe&ive part of the funnel. We increafe
the draught alfo by obliging all the air which enters the
chimney to come very near the fuel; therefore a low
mantle-piece will produce this effefl; alfo filling up all
the fpaces on each fide of the grate. When much air
gets in above the fire, by having a lofty mantle-piece,
the general mafs of air in the chimney cannot be much
heated. Hence it muft happen that the greateft draught
will be produced by bringing down the mantle-piece to
the very fuel} but this converts a fire-place into a fur¬
nace, and by thus fending the whole air through the fuel,
caufes it to burn with great rapidity, producing a prodi¬
gious heat; and this producing an increafe of afcenfional
force, the current becomes furioufiy rapid, and the heat
and confumption of fuel immenfe. If the fire-place be a
cube of a foot and a half, and the front clofed by a door,
fo that all the air muft enter through the bottom of the
grate, a chimney of 15 or 20 feet high, and fufficiently
wide to give paffage to all the expanded air which can
pafs through the fire, will produce a current which will
roar like thunder, and a heat fufficient to run the whole
infide into a lump of glafs.
All that is neceffary, however, in a chamber fire-place,
is a current fufhciently great for carrying up the fmoke
and vitiated air of the fuel. And as we want alfo the
enlivening flutter and light of the fire, we give the chim¬
ney-piece both a much great height and width than what
is merely neceflary for carrying up the fmoke, only wifli-
ing to have the current fuftkiendy determinate and fteady
for countera&ing any occasional tendency which it may
fometimes have to come into the room. By allowing a
greater quantity of air to get into the chimney, heated
only to a moderate degree, we produce a mpre rapid re¬
Effects of
Air’s prei-
fure.
newal of the air of the room : did we oblige it to come
fo much nearer the fire as to produce the fame re¬
newal ox the air in conlequtnce of a more rapid current,
we fliould produce an inconvenient heat. But in this v
country, where pit-coal is in general fo very cheap, we
carry this indulgence to an extreme •, or rather we have
not ftudied how to get all the defired advantages with
economy. A much fmaller renewal of air than we com¬
monly produce is abundantly wholefome and pleafant,
and we may have all the pleafure of the light and flame
of the fuel at much lefs expence, by contra&ing greatly
the pallage into the vent. The belt way of doing this
is by contracting the brick-work on each fide behind the
mantle-piece, and reducing it to a narrow parallelogram,
having the back of the vent for one of its long fides.
Make an iron plate to fit this hole, of the fame length,
but broader, fo that it may lie Hoping, its loiver edge
being in coutaft with the forefide of the hole, and its
upper edge leaning on the back of the vent. In this
position it flints the hole entirely. Now let the plate
have a hinge along the front or lower edge, and fold up
like the lid of a cheft. We lhall thus be able to en¬
large the paffage at pleafure. In a fire-place fit for a
room of 24 feet by 18, if this plate may be about 18
inches long from fide to fide, and folded back within
an inch or an inch and a half of the Avail, this Avill
allow paffage for as much air as will keep up a very
cheerful fire : and by raifing or lowering this Regi¬
ster, the fire may be made to burn more or lefs ra¬
pidly. A free paffage of half an inch will be fufficient
in w eather that is not immoderately cold. The prin¬
ciple on which this conftruftion produces its cfteft is,
that the air which is in the front of the fire, and much
wTarmed by it, is not allowed to get into the chimney,
where it Avould be immediately hurried up the vent,
but rifes up to the ceiling and is diftufed over the whole
room. This double motion of the air may be diflinft-
ly obferved by opening a little of the door and holding
a candle in the way. If the candle be held near the
floor, the flame will be blown into the room 3 but if
held near the top of the door, the flame will be blown
outward. _ 3*0
But the moft perfect method of warming an apart- Defcdption
ment in the temperate climates, where w’e can indulge o*ra ftove-
in the cheerfulnefs and fAveet air produced by an open Srate
fire, is Avhat we call a ftove-grate, and our neighbours c^‘‘l)e e“
on the continent call a chapelle, from its refemblance
to the chapels or oratories in the great churches.
In the great chimney-piece, which, in this cafe, may
be made even larger than ordinary, is fet a fmaller one
filted up in the fame ftiie of ornament, but of a fize
no greater than is fufficient for holding the fuel. The
fides and back of it are made of iron (caft iron is
preferable to hammered iron, becaufe it does not fo rea¬
dily calcine), and are kept at a fmall diftance from the
fides and back of the main chimney-piece, and are con¬
tinued down to the hearth, fo that the afh-pit is alfo fe-
parated. The pipe or chimney of the flove grate is
carried up behind the ornaments of the mantle-piece
till it rifes above the mantle-piece of the main chim¬
ney-piece, and is fitted A\dth a regifter or damper-plate
turning round a traverfe axis. The beft form of this
regifter is that which we have recommended for an or¬
dinary fire-place, having its axis or joint clofe at the
front 3 fo that when it is open or turned up, the burnt
air
PNEUMATICS.
Effects of
Air’s pref-
fure.
3^1
Effed of
its con-
ftrudion.
362
Mode of
■warming
apartments
by ftoves.
air and fmoke ftriking it obliquely, are direfted rvith
ceitainty into the vent, without any rifk of reverbera¬
ting and coming out into the room. All the reu or
the vent is (hut up by iron plates or brick-work out of
light. . #
The effeft of this conilruclion is very obvious. 1 ne
fuel, being in immediate contaft with the back and
Tides of the grate, heats them to a great degree, and
they heat the air contiguous to them. 1 his heated
air cannot get up the vent, becaufe the padages above
thefe (paces are (hut up. It therefore comes out into
the room *, fome of it goes into the real fire-place and
is carried up the vent, and the reft: rifes to the ceiling
and is diffufed over the room.
It is furpnfing to a perfon who does not confider
it with (kill how powerfully this grate warms a room.
Lefs than one-fourth of the fuel confumed in an ordi¬
nary fire-place is fufficient ; and this with the fame
cheerful blazing hearth and falutary renewal of air. It
even requires attention to keep the room cool enough.
The heat communicated to thofe parts in contaft with
the fuel is needlefsly great; and it will be a confiderable
improvement to line this part with very thick plates
of caft iron, or with tiles made of fire-clay which will
not crack with the heat. Thefe, being very bad con-
du&ors, will make the heat, ultimately communicated
to the air, very moderate. If, with all thefe precau¬
tions, the heat fhould be found too great, it may be
brought under perfecl management by opening paflages
into the vent from the lateral fpaces. iheie may be
■yalves or trap-doors moved by rods concealed behind
the ornaments.
Thus we have a fire-place under the mod complete
regulation, where we can always have a cheerful fire
without being for a quarter of an hour incommoded by
the heat j and we can as quickly raife our fire, u hen
too low, by hanging on a plate of iron on the^ iiont,
which (hall reach as low as the grate. Ihis in five mi¬
nutes will blow up the fire into a glow and the plate
may be fent out of the room, or let behind the (love-
grate out of fight.
The propriety of inclofing the afh-pit is not (o ob¬
vious 5 but if this be not done, the light allies, not
finding a ready pafiage up the chimney, will come out
into the room along with the heated air.
We do not confider in this place the various extra¬
neous circumftances which impede the current of aii in
our chimneys and produce fmoky houfes : thefe will be
treated of, and the methods of removing or remedying
them, under the article Smoke. We confider at prefent
only the theory of this motion in general, and the modi¬
fications of its operation arifing from the various purpofes
to which it may be applied.
Under this head we fhall next give a general ac¬
count and defeription of the method of warming apart¬
ments by ftoves. A STOVE in general is a fire-place
(hut up on all fides, having only a paffage for admitting
the air to fupport the fire, and a tube for carrying off
the vitiated air and fmoke ; and the air of the room
is. warmed by coming into conta6l with tne outfide of
the (love and flue. The general principle of conftruc-
tion, therefore, is very fimple. J he air muft be made
to come into as clofe contact as poflible with the nre, 01
even to pafs through it, and this in fuch quantities as
juft to confume a quantity of fuel fufficient for produ-
74-1
cing the heat required-, and the (love muft be fo con-
ftruded, that both the burning fuel, and the air which furjf
has been heated by it (hall be applied to as extenfive . .f
a furface as poftible of furnace, all in contact with the
air of the room 5 and the heated air within the (love
muft not be allowed to get into the funnel which is to
carry it off till it is too much cooled to produce any
confiderable heat on the outfide oi the do re.
In this temperate climate no great ingenuity is ne-
ceffary for warming an ordinary apartment j and ftoves
are made rather to pleafe the eye as furniture than as
economical (ubftitutes for an open fire or equal calori¬
fic power. But our neighbours on the continent, and
efpecially towards the north, where tne cold of winter
is intenle and fuel very dear, have bellowed much at¬
tention on their conftruclion, and nave combined mge-
nious economy wdth every elegance 01 form. . Nothing
can be handfomer than the ftoves of layencerie that aie
to be feen in French Flanders, or the Ruffian ftoves at
St Peterfburgh, finiihed in (lucco. Our readers will
not, therefore, be difpleafed with a delcription of them.
In this place, however, we (hall only confider a (love in
general as a fubjeft of pneumatical difeuflion, and we
refer our readers to the article Stove (or an account of
them as articles of domeftic accommodation. GeiSl
The general form, therefore, of a (love, and of which ^ of a,
all others are only modifications adapted to circumftances ^ove>
of utility or tafte, is as follows :
MIKL (fig. 79.) is a quadrangular box of any fize Fig 79.
in the directions MILK. The infide width from front
to back is pretty conftant, never lefs than ten inches,
and rarely extending to 20 j the included fpace is di¬
vided by a great many partitions. I he lowcft chamber
AB is the receptacle for the fuel, which lies on the
bottom of tire ftove without any grate ^ this fire-place
llciS cl door AO turning on hinges, and in this door is
a very (mall wucket P : the roof of the fire-place ex¬
tends to within a very few inches of the iarther end,
leaving a narrow paffage B for the (tame. T he next
partition c C is about eight inches higher, and reaches
almoft to the other end, leaving a narrow paffage for
the flame at C. The partitions are repeated above, at
the diftance of eight inches,, leaving paffages at the
ends, alternately difpofed as in the figure j the laft of
them H communicates with the room vent, i his com¬
munication may be regulated by a plate ot iron, which
can be Aid acrofs it by means of a rod or handle w hich
comes through the fide. Ihe more ufual w ay of (hut¬
ting up this paffage is by a fort of pan or bowl of earthen
ware, which is whelmed over it wdth its brim reiting in
fand contained in a groove formed ail round the hole.
This damper is introduced by a door in the.front, which,
is then (hut. The whole is fet on low pillais, io that
its bottom may be a few inches from the floor of the
room : it is ufually placed in a corner, and the apart¬
ments are fo difpofed that their chimneys can be joined
in (tacks as with us.
Some draw or wood-fhavings are firft burnt on the
hearth at its farther end. This warms the air in the
ftove, and creates a determined current. The fuel is-
then laid on the hearth clofe by- the door, and pretty
much piled up. It is now kindled 5 and the cunent be¬
ing already directed to the vent, there is no danger of*>
any fmoke coming out into the room. Lffectualb to-'
prevent tiffs, the door is (hut, and the wicket P opem.
ccL'-
742
Eftecb of
Air’s prtf-
fure.
 v 
. 3^4
Aim and
effeils of
this con-
flruAion.
ed. TTie air fupplied by tins, being dir eel ed to the
middle or bottom of the fuel, quickly kindles it, and
^ the operation goes on.
The aim of this conffrucfion is very obvious. The
flame and heated air are retained as long as poflible
within the body of the flove by means of the long paf-
fages; and the narrownefs of thefe paffages obliges the
flame to come in contadl with every particle of loot, fo
as to con fume it completely, and thus convert the whole
combuftible matter of the fuel into heat. For want of
this a very confiderable portion of our fuel is wafted by
our open fires, even under the very heft management :
the foot which flicks to our vents is very inflammable,
and a pound weight of it will give as much if not more
heat than a pound of coal. And what flicks to our
vents is very inconfiderable in comparifon with what
efcapes unconfirmed at the chimney top. In fires of
green wood, peat, and fome kinds of pit-coal, nearly
one-fifth of the fuel is loft in this way •, but in thefe
ftoves there is hardly ever any mark of foot to be feen j
and even this fmall quantity is produced only after
lighting the fires. The volatile inflammable matters are
expelled from parts much heated indeed, but not fo hot
as to burn •, and fome of it charred or half burnt cannot
be any further confirmed, being enveloped in flame and
air already vitiated and unfit for cornbuftion. But when
the flove is well heated, and the current brilk, no part
of the foot efcapes the adtion of the air.
I he hot air retained in this manner in the body of
the Hove is applied to its tides in a very extended furface.
To increafe this flill more, the ftove is made narrower
from front to back in its upper part; a certain breadth
is neceffary below, that there may be room for fuel. If
this breadth were pveferved all the way up, much heat
would be loft, becaufe the heat communicated to the
partitions of the ftove does no good. By diminifhing
their breadth, the proportion of ufeful furface is in°
creafed. The whole body of the ftove may be confider-
ed as a long pipe folded up, and its effedt would be the
grealeft poflible if it really were fo •, that is, if each par¬
tition C, r/D, &c. were fplit into two, and a free
paffage allowed between them for the air of the room.
Something like this will be obferved afterwards in fome
Ge rman ftoves.
It is with he fame v:efv of making an extenfive ap¬
plication of a hot furtace to the air, that t'.e ftove is not
built in the wall, not even in contadl with it, nor with
the floor: for by its detached fi'uation, the air in con-
tadt with the back, and with the bottom (where it is
hotteft), is warmed, and contributes at leal! one half of
the whole effedt; for the great heat of the bottom
makes its efFedt on the air of the room at leaft equal
to that of the two ends. Sometimes a ftcre makes part
of the wall between two fmall rooms, and is found fuf-
ficient.
It muft be remarked, on the whole, that the effedl of
a ftove depends much on keeping in the room the air
already heated by it. This is fo remarkably the cafe,
that a fmall open fire in the fame room will be fo far
from increasing its heat, that it will greatly diminifh it :
it will even draw the warm air from a fuite of adjoining
apartments. This is diftinclly obferved in the houfes
of the Englilh merchants in St Peterfburgh : their
habits of life in Britain make them uneafy without an
©pen fire in their fitting rooms; and this obliges them
PNEUMATICS.
to heat all their ftoves twice a-day, and their houfes are Me efts of
cooler than thofe of the Ruffians who heat them only Air's pref.
once. In many German houfes, efpecially of the lower iure*
clais, the fire-place of the ftove does not open into the
w.om, out into the yaid or a lobby, where all the fires
are lighted and tended; by this means is avoided the
expence of warm air which muft have been carried off
by the ftove : but it is evident, that this muft be very
unpleafant, and cannot be wholelome. We muft breathe
the fame quantity of ftagnant air loaded with all the va¬
pours and exhalations which muft be produced in every
inhabited place. Going into one of thefe heufes from
the open air, is like putting one’s head into a ftew-pan
or under a pie-cruft, and quickly naufeates us who are
accuftomed to frefii air and cleanlinefs. In thefe coun¬
tries it is a matter almoft of neceflity, to fumigate the
rooms with frankincenfe and other gums burnt. The
cenftr in ancient worfhip was in ail probability an utenfil
introduced by neceftity for fweetening or rendering to¬
lerable the air of a crowded place : and it is a conftanfc
praftice in the Ruffian houfes for a fervant to go round
the room after dinner, waving a cenier with feme gums
burning on bits of charcoal.
The account now given of ftoves for heating rooms, Q(-^
and of the circumftances which muft be attended to in walls in
their conftruflion, will equally apply to hot walls in gardening,
gardening, whether within or without doors. The on- &cv
ly new circumftance which this employment of a flue in¬
troduces, is the attention which muft be paid to the equa¬
bility of the heat, and the gradation which muft be ob¬
ferved in different pv rts of the building. The heat in the
flue gradually diminiffies as it recedes from the fire-place,
becaufe it is continually giving out heat to the flue. It
muft therefore be fo conduced through the building by
f equent returns, that in every part there may be a
mixture of warmer and cooler branches of the flue, and
the final chimney fhould be clofe by the fire-place. It
would, however, be improper to run the flue from the
end of the floor up to the ceiling, where the fecond ho¬
rizontal pipe would be placed, and then return it down¬
ward again and make the third horizontal flue adjoining
to the fix ft, &c. This would make the middle of the
wall the coldeft. If it is the flue of a greenhoufe, this
would he highly improper, becaufe the upper part of
the wall can be very little employed •, and in this cafe it
is better to allow the flue to proceed gradually up the
wallin its different returns, by which the loweft: part
would be the warmeft, and the heated air will afeend
among the pots and plants; but in a hot wall, where
the trees are to receive heat by contaft, fome approxi¬
mation tq the above method may be ufeful.
In the hypocaufta and fudaria of the Greeks and Ro¬
mans, the flue was conducted chiefly under the floors. 3^
Malt-kilns are a fpecies of ftove which merit our at- Malt kiln*
tention. Many attempts have been made to improve a *PtCies
them on the principle of flue ftoves •, but they have been itove* •
unfuccefsful, becaufe heat is not what is chiefly wanted
in malting: it is a copious current of very dry air to
carry off the molfture. We muft refer the examination
of this iubjeft alfo to the article Stove, and proceed to
confider the current of heated air in the chief varieties of
furnaces. _ ^
All that is to be attended to in the different kinds of Of the cur-
melting furnaces is, that the current of air be fufficientlyrent of air
rapid, and that it be applied in as extenfive a furface asmeltin£
poffible CCS
Effect* of
Air’o pref-
fure.
368
ip reverbe¬
ratory far-
aaces,
P N E U M
poflible to the fubftanee to be melted. ’J.'he more rapid
the current it is the hotter, becaufe it is confuming
more fuel} and therefore its effect increafes in a higher
proportion than its rapidity. It is doubly c '’ectual if
twice as hot ^ and if it then be twice as rapid, there is
twice the quantity of doubly hot air applied to the iub-
jeft ; it would therefore be four times more powerful.
This is procured by railing the chimney of the furnace
to a greater height. The clofe application of it to the
fubjeft can hardly be laid down in general terms, be¬
caufe it depends on the precife circumflances of each
cafe.
In reverberatory furnaces, fuch as refining furnaces
for gold, filver, and copper, the flame is made to play
over the furface of the melted metal. This is produced
entirely by the form of the furnace, by making the arch
of the furnace as low as the circumftances of the mani¬
pulation will allow. See Furkace. Experience has
pointed out in general the chief circumftances of their
conftrucfion, viz. that the fuel fliould be at one end on
a grate, through which the air enters to maintain the
fire j and that the metal fhould be placed on a level
floor between the fuel and the tall chimney which pro-
duces the current. But there is no kind of furnace
more variable in its effefl, and almoft evfcry place has
a fmall peculiarity of conftruftion, or which its pre-emi¬
nence is refted. This has occafioned many whimfical
varieties in their form. This uncertainty feems to de¬
pend much on a circumftance rather foreign to our pre-
fent purpofe ; but as we do not obferve it taken notice
of by mineralogical writers, we beg leave to mention
it here. It is not heat alone that is wanted in the re¬
fining of filver by lead, for inftance. We muft make
a continual application to its furface of air, which has
not contributed to the combuftion of the fuel. Any
quantity of the botteft air, already faturated with the
fuel, may play on the furface of the metal for ever, and
keep it in the ftate of mold perfeft fufion, but without
refining it in the leaft. Now, in the ordinary conftruc-
tlon of a furnace, this is much the cafe. If the whole
air has come in by the grate, and ’paffed through the
middle of the fuel, it can hardly be otherwife than near¬
ly faturated with it; and if air be alfo admitted by the
door (which is generally done or fomething equivalent),
the pure air lies above the vitiated air, and during the
paffage along the horizontal part of the furnace, and
along the furface of the metal, it ftill keeps above it, at
leaft there is nothing to promote their mixture. Thus
the metal does not come into contaft with air fit to aft
on the bafe metal and calcine it, and the operation of
refining goes on ilowly. Trifling circumftances in the
form of the arch or canal may tend to promote the
jumbling of the airs together, and thus render the ope¬
ration more expeditious; and as thefe are but ill un-
derftood, or perhaps this circumftance not attended to,
no wonder that we fee thefe conftdered as fo many nof-
trums of great importance. It were therefore worth
■while to try the effeft of changes in the form of the
roof direfted to this very circumftance. Perhaps feme
little prominence down from the arch of the reverbera¬
tory would have this effeft, by fuddenly throwing the
current into confufion. If the additional length of paf¬
fage do not cool the air too much, we fhould think that
if there were interpofed between the fuel and the rc-
A T I e S. 743
fining floor a paffage twilled like a cork-fcrew, making Effetfs of
juft half a turn, it would be moft efteftual: for we ima- fur*e. "
gine, that the two airs, keeping each to their refpeftive
tides of the palfage, would by this means be turned up-
fide down, and that the pure ftratum would now be in
contaft with the metal, and the vitiated air would be
above it. .369
The glafshoufe furnace exhibits the chief variety in and in the
the management of the current of heated air. In this gtafs-houfe
it is neceflary that the hole at which the workman dips *urnaces’
his pipe into the pot ftiall be as hot as any part of the
furnace. This could never be the cafe, it the furnace
had a chimney fituated in a part above the dipping-
hole j for in this cafe cold air would immediately ruth
in at the hole,- play over the furface of the pot, and go
up the chimney. To prevent this the bole itfelf is made
the chimney 5 but as this would be toofhort, and would
produce very little current and very little heat, the whole
furnace is let under a tall dome. Thus the heated air
from the real furnace is confined in this dome, and con-
ftitutes a high column of very light air, which will there¬
fore rife with great force up the dome, and efcape at
the top. The dome is therefore the chimney, and will
produce a draught or current proportioned to its height.
Some are raifed above a hundred feet. When all the
doors of this houfe are Unit, and thus no fupply given
except through the fire, the current and heat become
prodigious. This, however, cannot be done, beeaule
the workmen are in this chimney, and muft have re-
fpirable air. But notwithftanding this fupply by the
houfe-doors, the draught of the real furnace is vaftly
increafed by the dome, and a heat produced lufficient
for the work, and which could not have been produced
without the dome. 370
This has been applied with great ingenuity and effeft Improve-
to a furnace for melting iron from the ore, and an iron™611* °f
finery, both without a blaft. The common blaft iron|j
furnace is well known. It is a tall cone with the apexmeitinx
undermoft. The ore and fluxes are thrown into this iron from..
cone mixed intimately with the fuel till it is fdll, andtfieore-
the blaft of moft powerful bellows is direfted into the
bottom of this cone through a hole in the fide. The
air is thrown in with fuch force, that it makes its way
through the tnafs of matter, kindles the fuel in its paf¬
fage, and fluxes the materials, which then drop down
into a receptacle below the blaft-hole, and thus the paf¬
fage for the air is kept unobftrufted. It was thought
impoflible to produce or maintain this current without
bellows-, but Mr Cotterel, an ingenious founder, tiied
the effeft of a tall dome placed over the mouth of the
furnace, and though it was ndt half the height of many
glafshoufe domes it had the defired effeft. Confider-
able difficulties, however, occurred j and he had not
furmounted them all when he left the neighbourhood of
Edinburgh, nor have we fln,ce heard thatjie has brought
the invention to perfeftion. It is extremely difficult to
place the holes below, at which the air is to enter, at
fuch a precife height as neither to be choked by the
melted matter, nor to leave ore and ftones below7 them
unmeltedq"but the invention is very ingenious, and will
be of irnmenfe fervice if it can be perfefted ; for in ma¬
ny places iron ore is to be found where water cannot be
had for working a blaft furnace.
The laft application which we fhall make of the cur¬
rents ■
744
Effedts of
Air’s pref-
fure.
37r
Currents of
air applied
to free
mines,
I5iips, pri-
frms, 8tc.
of noxious
air.
P N E U M A T I C S.
. 372
Air necef-
fary for the
combuftion
.0 ifuel.
rents produced by beating the air is to the freeing mines,
(hips, prifons, &c. from the damp and noxious vapours
which frequently infeit them.
As a drift or work is carried on in the mine, let a
trunk of deal boards, about 6 or 8 inches fquare, be
laid along the bottom of the drift, communicating tvith
a trunk carried up in the corner of one of the (hafts.
Let the top of this lait trunk open into the afh-pit of a
fmall furnace, having a tall chimney. Let fire be kin¬
dled in the furnace} and when it is well heated, (hut
the fire-place and alh-pit doors. There being no other
fupply for the current produced in the chimney of this
furnace, the air will flow into it from the trunk, and
will bring along with it all the offenfive vapours. This
is the moft eft'eClual method yet found out. In the
fame manner may trunks be conduced into the alh-pit
of a furnace from the cells of a prifon or the wards of an
hofpital.
In the account which we have been giving of the
management of air in furnaces and common fires, we
have frequently mentioned the immediate application of
air to the burning fuel as neceflary for its combuftion.
This is a general fa<5t. In order that any inflammable
body may be really inflamed, and its combuilible matter
confumed and allies produced, it is not enough that the
body be made hot. A piece of charcoal inclofed in a
box of iron may be kept red hot for ever, without waft¬
ing its fubftance in the fmalleft degree. It is farther
neceflary that it be in contact with a particular fpecies
of air, which conftitutes about three-fourths of the air of
the atmofphere, viz. the vital air or oxygen of Lavoifler.
It wTas called empyreal air by Scheele, who firft obferved
its indifpenfable ufe in maintaining fire : and it appears,
that, in contributing to the combuftion of an inflam¬
mable body, this air combines with fome of its ingredi¬
ents, and becomes fixed air, fuffering the fame change as
by the breathing of animals. Combuftion may therefore
be confidered as a folution of the inflammable body in
air. This doftrine was firft promulgated by the cele¬
brated Dr Hooke in his Micrographia, publiftied in
1660, and afterwards improved in his treatife on Lamps.
It is now completely eftabliftied, and confidered as a new
difcovery. It is for this reafon, that in fire-places of all
•kinds wre have dire&ed the conftruftion, fo as to pro¬
duce a clofe application of the air to the fuel. It is
quite needlefs at this day to enter into the difcuflions
which formerly occupied philofophers about the manner
in which the preffure and elafticity of the air promoted
combuftion. Many experiments were made in the 17 th
century by the fivft members of the Royal Society, to
difcover the office of air in combuftion. It was thought
that the flame was extinguilhed in rare air for want of a
preffure to keep it together 5 but this did not explain its
extinction when the air was not renewed. Thefe expe¬
riments are ftill retained in courfes of experimental
philofophy, as they are judicioufly ftyled ; but they give
little or no information, nor tend to the illuftration of
any pneumatical doctrine 5 they are therefore omitted
in this place. In ftiort, it is now fully eftablifhed, that
it is not a mechanical but a chemical phenomenon. We
can only inform the chemift, that a candle will confume
fafter in the low countries than in the elevated regions of
Quito and Gondar, becaufe the air is nearly one half
denfer below, and will act proportionally fafter in de-
compofing the candle.
We (hail conclude this part of our fubjeCt with the Pneumatic
explanation of a curious phenomenon obferved in many Engines-1
places. Certain fprings or fountains are obferved to v” '
have periods of repletion and fcantinefs, or feem to ebb Curicus^ef-
and flow at regular intervals 5 and fome of thefe periods feCt of the
are of a complicated nature. Thus a -well will have fe-au'’s Pre^'
veral returns of high and low water, the difference of l~ure*
which gradually increafes to a maximum, and then di-
minilhes, juft as wre obferve in the ocean. A very inge¬
nious and probable explanation of this has been given in
N° 424. of the Philofophical Tranfactions, by Mr At¬
well, as follows.
Let ABCD (fig. 80.) reprefent a cavern, into which Fig. 8».
water is brought by the fubterraneous paffage OT. Let
it have an outlet MNP, of a crooked form, with its
higheft part N confiderably raifed above the bottom of
the cavern, and thence hoping downwards into lower
ground, and terminating in an open well at P. Let
the dimenfions of this canal be fuch that it will difcharge
much more water than is fupplied by TO. All this is
very natural, and may be very common. The effeft of
this arrangement will be a remitting fpring at P: for
when the cavern is filled higher than the point N, the
canal MNP will a<!ft as a fyphon •, and, by the condi¬
tions affumed, it wTill difcharge the water fafter than
TO fupplies it j it will therefore run it dry, and then
the fpring at P will ceafe to furnifti water. After fome
time the cavern will again be filled up to the height N,
and the flow at P will recommence.
If, befides this fupply, the well P alfo receive water
from a conftant fource, we (hall have a reciprocating
fpring.
The fituation and dimenfions of this fyphon canal,
and the fupply of the feeder, may be fuch, that the ef¬
flux at P will be conftant. If the fupply increafe in a
certain degree, a reciprocation will be produced at P
with very fhort intervals \ if the fupply diminfthes confi¬
derably, we ftiall have another kind of reciprocation
with great intervals and great differences of v/ater.
If the cavern have another fimple outlet R, new va¬
rieties will be produced in the fpring P, and R will af¬
ford a copious fpring. Let the mouth of R, by which
the water enters into it from the cavern, be lower than
N, and let the fupply of the feeding fpring be no great¬
er than R can difcharge, we {hall have a conftant Ipring
from R, and P will give no water. But fuppofe that
the main feeder increafes in winter or in rainy feafons,
but not fo much as will fupply both P and R, the ca¬
vern will fill till the water gets over N, and R will be
running all the while j but foon after P has begun to
flow, and the water in the cavern finks below R, the
ftream from R will flop. The cavern will be emptied
by the fyphon canal MNP, and then P will flop. The
cavern will then begin to fill, and when near full R
will give a little water, and foon after P will run and R
ftop as before, &c.
Defaguliers (hows, vol. ii. p. 177, &c. in what man¬
ner a prodigious variety of periodical ebbs and flows may¬
be produced by underground canals, which are extreme¬
ly fimple and probable.
374
We (hall conclude this article with the deferiptions Account of
of fome pneumatical machines or engines which have not pneu-
been particularly noticed under their names in the (or-m.atlc en'
i r 1 • 1 gxnes.
mer volumes ot this work.
Bellows
4
P N E U M
Pneumatic Bellows are of rcoft extenfive and important ufe j and
tjigincs. vvjt) p>e of fervice to defcribe fuch as are of uncommon
' ■ ^ ' conltrufHon and great power, fit for the great operations
in metallurgy.
It is not the impullive force of the blaft that is want¬
ed in rnoft cafes, but merely the copious fupply of air,
to produce the rapid combutlion of inflammable matter \
and the fervice would be better performed in general if
this could be done with moderate velocities, and an ex¬
tended furface. What are called air-furnaces, where a
confiderable furface of inflammable matter is aefed on at
once by the current which the mere heat of the expend¬
ed air has produced, are found jnore operative in pro¬
portion to the air expended than blall rurnaces animated
by bellows ; and we doubt not but that the method pro-
pofed by Mr Cotterel (which we have already mention¬
ed) of increafing this current in a melting furnace by
means of a dome, will in time fuperfede the blaft fur¬
naces. There is indeed a greatimpulflve force icijuiied
in fpme cafes $ as for blowing oft the fcorise from the
furface of filver or copper in refining furnaces, or for
keeping a clear paffage for the air in the great iron lur-
In general, however, we cannot procure tms abun¬
dant fupply of air any other way than by giving it^ a
preat velocity by means oi a great prefluie, fo that tne
general conftru&ion of bellows is pretty much the fame
in all kinds. The air is admitted into a very large ca¬
vity, and then expelled from it through a fmall bohn
The furnaces at the mines having been greatly enlar¬
ged ; it was neceffary to enlarge the bellows alio : and
the leathern bellows becoming exceedingly expenfive,
wooden ones were fubftituted in Germany about the be¬
ginning of the 17th century, and from them became ge-
Plate neral through Europe. I hey confifl 01 a wooden box
ccccxxxn. ABCPFE (fig. 92.), which has its top and two fides
Fl--52- flat or ftraight, and the end BAE <? formed into an
arched or cylindrical furface, of which the line 1' P at
the other end is the axis. Ibis box is open below, and
receives within it thefhallow box ErIGINIVIL (fig. 93*)?
which exaftly fills it. The line EP of the one coincides
with FP of the other, and along this line is a fet of
hinges on which the upper box turns as it nies and finks.
The lower box is made faft to a frame fixed in the
ground. A pipe GO proceeds from the end of it, and
terminates at the furnace, where it ends in a fmall pipe
called the fewer or tuyere. This lower box is open
above, and has in its bottom two large valves \\,
fig. 94. opening inwards. The conducting pipe is fome-
times furnifhed with a valve opening outwards, to pre¬
vent burning coals from being fucked into the bellows
when the upper box is drawn up. 1 he joint along PI
is made tight by thin leather nailed along it. i he fides
and ends of the fixed box are made to fit the fides and
curved end of the upper box, fo that this laft can be
raifed and lowered round the joint FP without fcnfible
friCfion, and yet without fuffering much air to efcape :
but as this would not be fuflficiently air-tight by reafon
of the fhrinkittg and warping of the wood, a rarther
Contrivance is adopted. A {lender lath of wood, divided
into feveral joints, and covered on the outer edge with
very foft leather, is laid along the upper edges of the
fides and ends of the lower box. I bis lath is fo bread,
that when its inner edge is even with the infide of the
box, its outer edge projefts about an inch. It is kept
VOL. XVI. Part II.
Fig 93-
Fig 94.
A T I C S. 745
in this pofition by a number of fteel wires, which are P^umanc
driven into the bottom of the box, and tland up touch- .„_.j
ing the fides, as reprefented in fig. 95* where a o c are jyg 9
the wires, and e the lath, projecting over the outiide of
the box. By this contrivance the laths are preffed cioie
to the fides and curved end of the moveable box, and ^
the fpring wires yield to all their inequalities. A oai
of wood RS (fig. 92.*) is fixed to the upper board, by
which it is either raifed by machinery, to fink again by
its own weight, having an additional load laid on it, or
it is forced downward by a crank or wiper of the ma¬
chinery, and afterwards raifed.
The operation here is precifely fimilar to that of
blowing with a chamber-bellows. W hen the board is
lifted up, the air enters by the valves V, V, fig. 94. and
is expelled at the pipe by deprefiing tne boards.
There is therefore no occafion to infift on this point.
Thefe bellows are made of a very great fize, AD be¬
ing 16 feet, AB five feet, and the circular end AE alio
five feet. The rife, however, is but about 3 or 34 feet.
They expel at each firoke about 9^ cuoio feet 01 air,
and they make about 8 ftrokes per minute.
Such are the bellows m general uie on the continent.
We have adopted a different form in this kingdom, which
feems much preferable. We ufe an iron or wooden c\ -
linder, with a pifton Hiding along it. I his may be made
with much greater accuracy than the wooden boxes, at
lefs expence, if of wood, becaufe it may be of coopers
work, held together by hoops} but the great advantage
of this form is its being more eafily made air-tight. I he
pifton is furrounded with a broad itrap of thick and foil
leather, and it has around its edge a deep groove, in
which is lodged a quantity of wool. 1 his is caked the
packing or fluffing, and keeps the leather very cloteiy
applied to the inner furface of the cylinder. Iron cylin¬
ders may be very neatly bored and fmoothed, fo that the
pifton, even when very tight, will Hide along it very
fmoothly. To promote this, a quantity of black lead i#
ground very fine with water, and a little of this is imear-
ed on the infide of the cylinder from time to time.
The cylinder has a large valve, or fometimes two, in
the bottom, by which the atmoipheric air enters when
the pifton is drawn up. When the pifton is thruft down,
this air is expelled along a pipe of great diameter, whit 1
terminates in the furnace with a fmall orifice.
This is the fimpleft form of bellows which can be
conceived. It differs in nothing but fize from the bel¬
lows ufed by the rudeft nations. The Chint'e fmiths
have a bellows very fimilar, being a fquare pipe of wood
ABCDE (fig. 96.), with a fquare board G which ex- Fig. 96.
aftly fits it, moved by the handle EG. At the farther
end is the blaft pipe KK, and on each tide of it a valve
in the end of the fquare pipe, opening inwards. The
pifton is fufficiently tight for their purpofes without any
leathering.
The pifton of this cylinder bellows is moved by ma¬
chinery. In fome blaft engines the pifton is limply
raifed by the machine, and then let go, and it defeends
by its own weight, and compreifes the air below it to
fuch a degree, that the velocity of efflux becomes con-
ftant, and the pifton defeends uniformly : for this pur-
pofe it muft be loaded with a proper weight. This
produces a very uniform blaft, except at the very begin¬
ning, while the pifton falls fuddenly and compreffts the
air ; but in moft engines the pifton rod is forced down
5 B the
740 PNEUMATIC S.
^ie cylinder with a determined motion, by means of a
. i:^‘K ' , beam, crank, or other contrivance. This gives a more
unequal blaft, becaufe the motion of the pilton is necef-
farily flow in the beginning and end of the ftroke, and
quicker in the middle.
But in all it is plain that the blaft muft be defultory.
It ceafes while the pifton is rifmg 3 for this reafon it is
’dual to have two cylinders, as it was formerly ufual to
have two bellows which worked alternately. Sometimes
Tree or four are ufed, as at the Carron iron works.
.1 his makes a blaft abundantly uniform.
But an uniform blaft may be made With a Angle cy¬
linder, by making it deliver its air into another cylin¬
der, which has a pifton exadtly fitted to its bore, and
loaned with a futficient weight. The blowing cylinder
^ S'?- A BCD (fig. 97.) has its pifton P worked by a rod
NP, connected by double chains with the arched head
°f die working beam NO, moving round a gudgeon at
R. I he other end O of this beam is connected by the
rod OP, with the crank P(^ of a wheel machine 3 or it
may be connected with the pifton of a fleam engine, &c.
_&c. The blowing cylinder has a valve or valves E in
its bottom, opening inwards. There proceeds from it a
large pipe CF, which enters the regulating cylinder
C'lfKI, and has a valve at top to prevent the air from
getting back into the blowing cylinder. It is evident
‘ uat the air forced into this cylinder muft raife its pifton
E, and that it muft afterwards defcend, while the other
pifton is rifing. It muft defcend uniformly, and make
a perfectly equable blaft.
^ Obfervc, that if the pifton L be at the bottom when
the machine begins to work, it will be at the bottom
at the end of every ftroke, if the tuyere T emits as
much air as the cylinder ABCD furnifties 3 nay, it will
be a while at the bottom, for, while it was rifing, air
was ifiuing through T. This would make an interrupt¬
ed blaft. To prevent this, the orifice T muft be leflen-
e.d 3 but then there will be a furplus of air at the end of
each ftroke, and the pifton E will rife continually, and
at laft get to the top, and allow air to efcape. It is
juft poflible to adjuft circumftances, fo that neither (hall
happen. This is done eafier by putting a flop in the
way of the pifton, and putting a valve on the pifton, or
on the conducting pipe KST, loaded with a weight a
little fuperior to the intended elafticity of the air in the
cylinder. Therefore, rvhen the pifton is prevented by
(he flop from rifing, the fnifting valve, as it is called, is
forced open, the fuperfluous air efcapes, and the blaft
preferves its uniformity.
It may be of ufe to give the dimenfions of a machine
ct this kind, which has worked for fome years at a very
great furnace, and given fatisfadlion.
Ihe diameter of the blowing cylinder is 5-feet, and
the length of the ftreke is 6. Its pifton is loaded with
34 tons. It is worked by a fleam-engine whofe cylin¬
der is 3. feet 4 inches wide, with a fix feet ftroke. The
regulating cylinder is 8 feet wide, and its pifton is load¬
ed with 84 tons, making about 2.63 pounds on the fquare
inch 3 and it is very nearly in equilibrio with the load
on the pifton of the blowing cylinder. The conducing
pipe KST is’ 12 inches in diameter, and the orifice of
the tuyere was | of an inch when the engine was erefled,
but it has gradually enlarged by reafon of the intenfe
beat to which it is expofed. The fnifling valve is load¬
ed with 3 pounds on the fquare inch.
When the engine worked brilkly, it made 18 ftrokes Pneumatic
per minute, and there was always much air difeharged -Engines,
by the fnifting valve. When the engine made 15 ftrokes u—4—
per minute, the fnifting valve opened but feldom, fo that
things were nearly adjufted to this fupply. Each ftroke
of the blowing cylinder fent in 1 j 8 cubic feet of com¬
mon air. The ordinary preffure of the air being flip..
pofed 14I- pounds on an inch, the denfity of the air in
the regulating cylinder muft be — IiI785
14.75 ^
the natural denfity being 1.
This machine gives an opportunity of comparing the
expence of air with the theory. It muft (at the •rate
of 15 ftrokes) expel 30 cubic feet of air in a fecond
through a hole of inches in diameter. This gives
a velocity of near 20-0 feet per fecond, and of more
than 1600 feet for the condenfed air. This is vaftly
greater than the theory can give, or is indeed poflible 3
for air does not ruth into a void with fo great velocity.
It (hows with great evidence, that a vaft quantity of
air muft efcape round the two piftons. Their united
circumferences amount to above 40 feet, and they move
in a dry cylinder. It is impoflible to prevent a very
great lofs. Accordingly, a candle held near the edge
of the pifton L has its flame very much difturbed. This
cafe, therefore, gives no hold for a calculation 3 and it
fuggefts the propriety of attempting to diminith this
great wafte.
This has been very ingenioufly done (in part at leaft)
at fome other furnaces. At Omoah foundery, near
Glafgow, the blowing cylinder (alfo worked by a fleam
engine) delivers its air into a cheft without a bottom,
which is immerfed in a large cittern of water, and fup-
ported at a fmall height from the bottom of the cittern,
and has a pipe from its top leading to the tuyere. The
water ftands about five feet above the lower brim of the
regulating air-cheft, and by its preflure gives the moft
perfect uniformity of blaft, without allowing a particle
of air to get off by any other paffage befides the tuyere.
This is a very effeftual regulator, and muft produce a
great laving of power, becaufe a fmaller blowing cylin¬
der will thus fupply the blaft. We muft obferve, that
the lofs round the pifton of the blowing cylinder remains
undiminithed.
A blowing machine was erefled many years ago at
Chaftillon in France on a principle confiderably differ¬
ent, and which muft be perfectly air-tight throughout.
Two cylinders A, B (fig. 98.), loaded with great Plate
weights, were fufpended at the ends of the lever CD, cccfxxxi»r*
moving round the gudgeon E. From the top F, G FlS' 98‘
of each there was a large flexible pipe which united
in H, from whence a pipe KT led to the tuyere T.
There were valves at F and G opening outwards, or
into the flexible pipes 3 and other valves L, M, adjoin¬
ing to them in the top of each cylinder, opening in¬
wards, but kept ftiut by a flight fpring. Motion was
given to the lever by a machine. The operation of this
blowing machine is evident. When the cylinder A
was pulled down, or allowed to defcend, the water, en¬
tering at its bottom, compreffed the air, and forced it
along the paffage FHKT. In the mean time, the cy¬
linder B was rifing, and the air entered by the valve M.
We lee that the blaft will be very unequal, increafing
as the cylinder is immerfed deeper. It is needlefs to
deferibe this machine more particularly, becaufe we ftiall
give
pneumatics.
747
Pr.eumMlc give an account ot one winch we think peifeci in its
Engines, and which leaves hardly any thing to be defired
 ' in a machine of this fort. It was invented by Mr John
Laurie, land-furveyor in Edinburgh, about 15 years
ago, and improved in home reipedls lince his death by an
ingenious perfon of that city.
Fig.?*. ABCD (fig. 99.) is an iron cylinder, truly, bored
within, and evafated a-top like a cup. EtGII is ano¬
ther, truly turned both without and within, and a fmall
matter lels than the inner diameter of the firft cylinder.
This cylinder is clofe above, and hangs, from the end
of a lever moved by a machine. It is alfo loaded with
weights at N. KILM is a third cylinder, whofe out-
fide diameter is fomewhat lels than the infide diameter
of the fecond. This inner cylinder is fixed to the fame
bottom with the outer cylinder. The middle cylinder
is loofe, and can move up and down between the cuter
and inner cylinders without rubbing on either of them.
The inner cylinder is perforated from top to boi.tom
by three pipes OQ,, SV, PR. The pipes OQ, PR
have valves at their upper ends O, P, and communicate
with the external air below. The pipe SV has a hori¬
zontal part VW, which again turns upwards, , and has
a valve at top X. this upright part WX is in the
middle of a cittern of water f h k g. Into this cittern
is fixed an air-cheft a YZ b, open below, and hav¬
ing at top a pipe c d e terminating in the tuyere at the
furnace. __ ^
When the machine is at rett, the valves X, O, P,
are flrut by their own w'oights, and the air-chett is full
of water. When things are in this ftate, the middle
cylinder EFGH is drawn up by the machinery till its
lower brims F and G are equal with the top KM of the
inner cylinder. Now pour in water or oil between the
outer and middle cylinders : it will run dowm and fill
the fpace between the outer and inner cylinders. Let
it come to the top of the inner cylinder.
Now let the loaded middle cylinder defcend. It
cannot do this wnthout comprefling the air which is
between its top and the top of the inner cylinder.^ T ms
air being comprefled wall caufe the water to descend
between the inner and middle cylinders, and rife between
the middle and outer cylinders, fpreading into the cup 5
and as the middle cylinder advances dow’mvards, the
water will defcend farther within it and rife farther
without it. When it has got fo far down, and the air
has been fo much compreffed, that the difference between
the furface of the w^ater on the infide and outfide of
this cylinder is greater than the depth of wTater between
X and the furface of the water fg, air will go out by
the pipe SVW, and will lodge in the air-cheft, and
•will remain there if c be {hut, which we (hall fuppofe
for the prefent. Pufhing down the middle cylinder
till the partition touch the top of the inner cylinder,
all the air which was formerly between them will be
forced into the air-cheft, and will drive out water from
it. Draw up the middle cylinder, and the external
■ air will open the valves O, P, arid again fill the fpace
between the middle and inner cylinders •, for the valve
X will {hut, and prevent the regrefs of the condenfed
air. By pulhing down the middle cylinder a fecond
time, more air will be forced into the air-cheft, and it
will at laft efcape by getting out between its brims Y,
Z and the bottom of the ciftern 5 or if we open the paf-
fage c, it will pafs along the conduit c d e to the tuyere,
and form a blaft. . ^
The operation of this machine is fimilar to Mr Haf-
kins’s quickfilver pump deicribed by Defaguliers at
the end of the fecond volume of his Experimental Phi-
lofophy. The force which condenfes the air is the load
on the middle cylinder. The ufe of the water between
the inner and outer cylinders is to prevent this air from
efcaping j and the inner cylinder thus perfoims the othce
of a pifton, having no fridfion. It is neceffary that
the length of the outer and middle cylinders be greater
than the depth of the regulator-cittern, that there
may be a fufficient height for the water to rife between
the middle and outer cylinders, to balance the com¬
preffed air, and oblige it to go into the air-cheft. A
large blaft-furnace wall require the regulator-ciftern five
feet deep, and the cylinders about fix or feven feet
long.
It is in faft a pump without fridlion, and is perfedlly
air-tight. The quicknefs of its operation depends on
the fmall fpace between the middle cylinder and the two
others j and this is the only ufe of theie two. With
out thefe it w’ould be fimilar to the engine at Chaftillon,
and operate more unequally and ilowly. Its only im¬
perfection is, that if the cylinder begin its motion of
afeent or defeent rapidly, as it will do when worked
by a fleam-engine, there will be fome danger of water
dafhing over the top of the inner cylinder and getting
into the pipe SV \ but fhould this happen, an iffue
can eafily be contrived for it at V, covered with a load¬
ed valveV This will never happen if the cylinder is
moved by a crank.
One blowing cylinder only is reprefented here, but
two may be ufed.
We do not hefitate in recommending this form of
bellows as the moft perfeCl of any, and fit for all ufes
where {landing bellows are required. They will be
cheaper than any other fort for common purpofes. dor
a common foaiih’s forge they may be made with fquare
wooden boxes inftead of cylinders. They are alfo eafily
repaired. They are perfectly tight *, and they may.be
made with a blaft almoft perfectly uniform, by making
the ciftern in which the air-cheft Hands of confiderable
dimenfions. When this is the cafe, the height of water,
which regulates the blaft, will vary very little.
This may fuffice for an account of blaft machines.
The leading parts of their conftruftion have been de-
feribed as far only as was neceffary for underftanding
their operation, and enabling an engineer to ereft them
in the moft commodious manner. V.cws of complete
machines might have amufed, but they would not have
added to our reader’s information.
But the account is imperfedl unlefs we flrow how
their parts may be fo proportioned that they fiiall per¬
form what is expected from them. The engineer fhould
know what fize of bellows, and what load on the board
or pifton, and what fize of tuyere, will give the blaft:
which the fervice requires, and what force muft be em¬
ployed to give them the neceffary degree of motion.
We fhall accomplifh thefe purpofes by confidering the
efflux of the compreffed air through the tuyere. The
propofitions formerly delivered will enable us to afeer-
tain this.
That we may proportion every thing to the power
5 B 2 employed,
748
P N E U Tvl A T I C S.
iJneu
£ng-
mat!c employed, we mu ft recolleft, that if the pifton of a cy-
'nc'' Under employed for expelling air be prcffed down with
any force/>, it muit t e confidered as fuperadded to the
atmofpheric preffure P on the,fame piiton, in order that
we may compare the velocity v of efflux with the known
\elocity V with which air rufhes into a void. By v\?hat
has been formerly delivered, it appears that this velocity
r
:VxV
p
PX/>
!, where P is the preffure of the atmo-
fphere on the pifton, and p the additional load laid on it.
This velocity is expreiTed in feet per fecond ; and, when
multiplied by the area of the orif.ce (alfo expreffed in
fquare feet), it will give us the cubical feet of conden-
fed air expelled in a i'econd : but the bellows are always
to be filled again with common air, and therefore
we want to know the quantity of common air which
will be expelled; for it is this which determines the
number of ftrokes which muft be made in a minute, in
order that the proper fupply may be obtained. There¬
fore recolleft that the quantity expelled from a given
orifice with a given velocity, is in the proportion of the
denfity ; and that when D is the denfity of common air
produced by the preffure P, the denfity d produced by
P
——3 or if D be made 1, we
the preffure P+/’> is ID X
P+/>
have dz
’rJ
Therefore, calling the area of the orifice expreffed in
fquare feet O, and the quantity of common air, or the
cubic feet expelled in a fecond p, we have Q—V X O X
P+P
P
X
/„
^ P "VP i
it wall be fufficiently exafi for all praflical purpofes
to fuppofe P to be 15 pounds on every fquare inch of
the pifton 3 and p is then conveniently expreffed by the
pounds of additional load on every fquare inch : we may
alfo take V—1332 feet. 1
As the orifice through which the air is expelled is ge¬
nerally very fmall, never exceeding three inches in diame¬
ter, it will be more convenient to exprefsit in fquare inches 3
which being the of a fquaie foot, we {hall have
the cubic feet of common air expelled in a fecond, or
P
P -\-p
x p
:OX9-25
P
P+P
X
144
P p
—p—; and this feems to be as fimple an expreflion as
we can obtain.
This will perhaps be illuftrated by taking an example
in numbers. Let the area of the pifton be four fquare
feet, and the area of the round hole through which the
air is expelled be two inches, its diameter being 1.6,
and let the load on the pifton be 1728 pounds : this is
three pounds on every fquare inch. We have Pzrij,
/—3, P-f-/>ur:i8, and 0=23 therefore we will have
J1L
V i8
0 = 2x9.25 x
X —, —9.053 cubic feet of com¬
mon air expelled in a fecond. This will however be di-
miniftied at leaft one-third by the contraction of the jet 3
and therefore the fupply will not exceed fix cubic feet
per fecond. Suppofmg therefore that this blowing ma¬
chine is a cylinder or prifm of this dimenfion in its fec-
tion, the pifton fo loaded would (after having compref-
fed the air) defeend about 15 inches in a fecond : It Pneumatic
would firft fink one-fifth of the whole length of the cy- -Engine-.
Under pretty fuddenly, till it had reduced the air to the
denfity Tin aod would then delcend uniformly at the
above rate, expelling fix cubic feet of common air in a
fecond.
The computation is made much in the fame way for
bellows of the common form, with this additional cir-
cmnfiance, that as the loaded board moves round a
hinge at one end, the preffure of the load muft be calcu¬
lated accordingly. The computation, however, becomes
a little intricate, when the form of the loaded board is
not reClangular: it is almoft ufelefs when the bellows
have flexible fides, either like fmiths bellows or like
organ bellows, becaufe the change of figure during their
motion makes continual variation on the compreffing
powers. It is therefore chiefly with refpeCt to the
great wooden bellows, of which the upper board bides
down between the fides, that the above calculation is of
fervice.
The propriety, however, of this piece of information
is evident : we do not know precifely the quantity of
air neceffary for animating a furnace ; but this calcula¬
tion tells us what force muft be employed for expelling
the air that may be thought neceffary. If we have fixed
on the ftrength of the blaft, and the diameter of the cy¬
linder, we learn the weight with which the pifton muft
be loaded 3 the length of the cylinder determines its ca¬
pacity, the above calculation tells the expence per fe¬
cond 3 hence we have the time of the pifton’s coming
to the bottom. This gives us the number of ftrokes per
minute : the load muft be lifted up by the machine this
number of times, making the time of afeent precifely
equal to that of defeent 3 otherwife the machine will ei¬
ther catch and flop the defeent of the pifton, or allow it
to lie inactive for a while of each ftreke. Thefe circum-
ftances determine the labour to be performed by the ma¬
chine, and it muft be comlruckd accordingly. Thus
the engineer will not be affronted by its failure, nor wilt
he expend neediefs power and coft.
In machines which force the pifton or bellows-board
with a certain determined motion, different from what
antes from their own weight, the computation is ex¬
tremely intricate. When a pifton moves by a crank, its
motion at the beginning and end of each ftroke is flow,
and the compreffion and efflux is continually changing :
we can however approximate to a ftatement of the" force
required.
Every time the pifton is drawn up, a certain fpace
of the cylinder is filled again with air of the common
denfity 3 and this is expelled during the defeent of the
pifton. A certain number of cubic feet of common air
is therefore expelled with a velocity which perhaps con¬
tinually varies 3 but there is a medium velocity with which
it might have been uniformly expelled, and a preffure
correfponding to this velocity. To find this, divide the
area of the pifton by the area of the blaft-hole (or ra¬
ther by this area multiplied by 0.613, in order to take
in the eftedl of the contradled jet), and multiply the
length of the ftroke performed in a fecond by the quo¬
tient arifing from this divifion ; the produdl is the me¬
dium velocity of the air (of the natural denfity). Then
find by calculation the height through which a heavy
body muft fall in order to acquire this velocity 3 this is
the height of a column of homogeneous air which would
expel
P N E U M A T I C S.
Ptreamatitf expel'it wiih this velocity. The weight of this column
Eng*re'~- is the leaft force that cmi be exerted by the engine : but
* 'yr ' this force is too imali to o\’ercome the refinance in the
middle of the ftroke, and it is too great even for the end
of the (iroke, arid much too great for the beginning of
it. But if the machine is turned by a very heavy water-
wheel, this will act as a regulator, accumulating in it-
fcif the funerfluous force during the too favourable pofi-
lions of the crank, and exerting it by its v/s injita dur¬
ing the time of greateft effort. A force not greatly ex¬
ceeding the weight of this-column of air will therefore
fuffice. , On the other hand, if the ftrength of the blaft
be determined, which is the general bate of the problem,
this determines the degree of condenfadon of the air,
and the load on the fquare inch of the pifton, or the
mean force which the machine muff exert on it. A
table, which will be given prefently, determines the
cubic feet of common air expelled in a fecond, corre-
fponding to this load. This combined with the propofed
dimenSons of the cylinder, will give the defcent of the
piffon or the length of the llroke.
Thefe general obfervalions apply to all forms of bel¬
lows ; and without a knowledge of them no perfon can
erecf a machine for working them without total uncer¬
tainty or fervile imitation. In order, therefore, that they
mav be ufeful to fuch as are not accuftomed to the ma¬
nagement of even thefe Ample formulae, we infert the
following (hort table of the velocity and quantity of air
difcharged from a cylinder whofe pi It on is loaded with
the pounds contained in the nrft column on every fquare
inch. The fecond column contains the velocity with
which the condenfed air rufhes out through any fmall
hole; and the third column is the cubic feet difcharged
from a hole whofe area is a fquare inch ; column fourth
contains the mean velocity of air of the common den-
fity *, arid column fifth is the cubic feet of common air
difcharged ; the fixth column is the height in inches at
which the force of the blaft would fupport a column of
water if a pipe were inferted into the fide of the cylin¬
der. This is an extremely proper addition to fuch ma¬
chines, fhowing at all times the power of the machines,
and teaching us what intenfity of blaft is employed for
different purpofes. The table is computed from the
fuppofition that the ordinary preffure of the air is 15
pounds on a fquare inch." This is fomewhat too great,
and therefore the velocities are a little too fmall; but
the quantities difcharged will be found about one-third
too great (without affeCfing the velocities) on account of
i,he convergency of the ftream.
749
Pneutri;-1 ic
■Engint*.
II
239
333
404
457
500
544
582
611
642
666
693
71T
III IV
x.66
2.32
2.79
3-1?
3-48
3-7^
4'°3
4,24
4.46
4.67
4.84
5-°6
247
355
437
5*8
584
653
7*5
774
822
888
950
997
1.72
2.47
3*05
3.60
4.2
4- 53"
4.98
5- 38
<i*75
6.17
6.49
6.92
VI
This table extends far beyond the limits of ordinary
ufe, very few blaft-furnaces having a force exceeding 60
inches of water. '
We {hall conclude this account of blowing machines
with a defeription of a fmall one for a blowpipe. ^ ^
ABCD, fig. 100. is a veffel containing water, about n'
two feet deep. EFGH is the air-box of. the. blower,
open below, and having a pipe ILK riling up from it
to a convenient height; an arm ON which grafps this,
pipe carries the lamp N : the blowpipe LM comes from
the top of the upright pipe. PK£) is the feeding pipe,
reaching near to the bottom of the veffel.
Water being poured into the vefiel below, and its co¬
ver being put on, which fits the upright pipe, and
touches two ftuds <2, a, projecting from it, blow in a
quantity of air by the feeding pipe P£) j this expels the
water from the air-box, and occafions a preffure which,
produces the blaft through the blowpipe M.
In N° 54. of this article, we mentioned an applica¬
tion which has been made of Hero’s fountain, at Chem¬
nitz in Hungary, for railing water from the. bottom of
a mine. We lhall now give an account of this very in¬
genious contrivance.
In fig. 101. B reprefents the fource of water elevated Fig. 101.
above the mouth of the pit 136 feet. From this there
is led a pipe B b CD four inches diameter. This pipe
enters the top of a copper cylinder b c de, 8| feet high,
five feet diameter, and two inches thick, and it reaches
to within four inches of the bottom •, it has a cock at
C. This cylinder has a cock at F, aifft a very large
one at E. From the top be proceeds a pipe GHIP
two inches in diameter, which goes down the pit 96
feet, and is inferted into the top of another brafs cy¬
linder fghi, which is 6i feet high, four feet diameter,
and two inches thick, containing 83 cubic feet, which is
very nearly one half of the capacity of the other, viz.
of 170 cubic feet. There is another pipe NI of four
inches diameter, which rifes from within four inches of
the bottom of this lower cylinder, is foldered into its
top, and rifes to the trough NO, which carries oft' the
w-ater from the mouth of the pit. This lower cylinder
communicates at the bottom with the water L which
collects in the drains of the mine. A large cock K
ferves to admit or exclude this water *, another cock M,
at the top of this cylinder, communicates with the exter¬
nal air.
Now fuppofe the cock C Ihut, and all the reft open 5
the upper cylinder wall contain air, and the low^er cy¬
linder will be filled with water, becaufe it is funk fo
deep that its top is below the ufual furface of the mine-
w'aters. Now Ihut the cocks F, E, M, K, and open
the cock C. The w ater of the fource B muff run in
by the orifice D, and rife in the upper cylinder, com¬
prefling the air above it and along the pipe GHH',
and thus adling on the furface of the water in the lower
cylinder. It will therefore caufe it to rife gradually
in the pipe IN, where it will always be of fuch a height
that its weight balances the elafticity of the compreffed
air. Suppofe no iffue given to the air from the upper
cylinder, it would be compreffed into one-fifth of its
bulk by the column of 136 feet high for a column of
34 feet, nearly balances the ordinary elafticity of the air.
Therefore, when there is an iflue given to it through
the pipe GHH', it will drive the compreffed air along
this pipe, and it will expel water from the lower cylin¬
der.
PNEUMATICS.
75°
Pneumatic der. When the upper cylinder is full of water, there
i n-^ne • j will be 34 cubic feet of water expelled from the lower
cylinder. If the pipe IN had been more than 136 feet
long, tile water would have rilen 136 feet, being then
in equilibrio with the water in the feeding pipe B b CD
(as was (hown in N° 520> by the intervention of the
elaftic air j but no more water ivould have been ex¬
pelled from the lower cylinder than what fills this pipe.
But the pipe being only 96 feet high, the water will
be thrown out at N with a very great velocity. If it were
not for the great obffrudiions which water and air muff
meet with in their paiTage along pipes, it would iffue at N
with a velocity of more than 30 feet per fecond. It
ififues much more (lowly, and at lait the upper cylinder
is full of water, and the water wrould enter the pipe GH
and^ enter the lower cylinder, and without difplacing the
air in it, would rife through the difeharging pipe IN,
and run otr to wade. To prevent this there bangs in
the pipe fIG a cork ball or double cone, by a brafs
wire which is guided by holes in two crofs pieces in the
pipe HG. When the upper cylinder is filled-with water,
this cork plugs up the orifice G, and no water is wafted 5
the influx at X) now flops. But the lower cylinder con¬
tains compreffed air, which would balance water in a
difeharging pipe 136 feet high, whereas IN is only 96.
Therefore the water will continue to flow at N till the
air has fo far expanded as to balance only 96 feet of
water, that is, till it occupies one fourth of its ordinary
bulk, that is, one-fourth of the capacity of the upper cy¬
linder, or 4-24 cubic feet. Therefore 42^ cubic feet
will be expelled, and the efflux at N will ceafe; and the
lower cylinder is about one half full of water. When
the attending workman obferves this, be flints the cock
C. He might have done this before, had he known
when the orifice G was flopped 5 but no lofs enfues
from the delay. At the fame time the attendant opens
the cock E, the water iflues with great violence, being
prefled by the condenfed air from the lower cylinder.
It therefore iiTues with the fum of its own weight and
of this compreffion. Thefe gradually decreafe together,
by the efflux of the water and the expanfion of the air;
but this efflux flops before all the water has flowed out 5
for there is 421 feet of the low'er cylinder occupied by
air. This quantity of water remains, therefore, in the
upper cylinder nearly : the workman knows this, be-
caufe the difeharged water is received firfl of all into
a veflfel containing three-fourths of the capacity of the
upper cylinder. Whenever this is filled, the attendant
opens the cock K by a long rod which goes down
the flia.t j this allows the water of the mine to fill the
lower cylinder, allows the air to get into the upper cy¬
linder, and this allows the remaining water to run out
of it.
And thus every thing is brought into its firfl condi¬
tion ; and when the attendant fees no more water come
out at E, he fhuts the cocks E and M, and opens the cock
C, and the operation is repealed.
I here is a very furprifing appearance in the working
of this engine. When the efflux at N has flopped, if
the cock F be opened, the water and air rufli out toge¬
ther with prodigious violence, and the drops of water
are changed into hail or lumps of ice. It is a fight
ufually fhown to ftrangers, who are defired to hold their
hats to receive the blaft: of air : the ice comes out with
fuch violence as frequently to pierce the hat like a piflol
3
buuet. 7 his rapid congelation is a remarkable inftafiCe Pnetimiitkr
of the general fact, that air by fuddenly expanding, ge- -Engines,
neiates cold, its capacity for "heat being increafed. Thus ’" 'v
the peafant cools his broth by blowing over the fpocn,
even from warm lungs: a ftream of air from a pipe is
always cooling.
The above account of the procedure in working this
engine (hows that the efflux both at N and E becomes
very flow near the end. It is found convenient therefore
not to wait for the complete difeharges, but to turn ihe
cocks when about 30 cubic feet ol water have been dif¬
eharged at N : more work is done in this way. A gen¬
tleman of great accuracy and knowledge of thefe fubjedls
took the trouble, at our defire, of noticing particularly
the performance of the machine. He obferved that
each flroke, as it may be called, took up about three mi¬
nutes and one-eighth j and that 32 cubic feet of water
were cliicharged at N, and 66 were expended at E. The
expence therefore is 66 feet of w-afer falling 136 feet,
and the performance is 32 raifed 96, and they are in
the proportion of 66x136 to 32x96, or of 1 to
0.3422, or nearly as 3 to 1. 7 his is fuperior tc the
performance of the mofl perfedl underfhot mill, even
when all fri&ion and irregular obftru£lions are negleft-
ed ; and is not much inferior to any overfhot pump-mill
that has yet been eredled. When we retledl on the
great obflrudlions wfflich water meets with in its paflfage
through long pipes, we may be affured that, by dou¬
bling the fize of the feeder and difeharger, the perfor¬
mance of the machine will be greatly improved 5 we do
not hefilate to fay, that it would be increafed one-
third : it rs true that it will expend more w ater j but
this will not be nearly in the fame proportion ; for moil
of the deficiency of the machine arifes from the needlefs
velocity of the firfl efflux at N. 7 he difeharging pipe
ought to be 110 feet high, and not give fenfiblylels water.
1 hen it mull be confidered how inferior in original
expence this fimple machine muff be to a mill of any
kind which w’culd raife 10 cubic feet 96 feet high in a
minute, and howT fmall the repairs on it need be, when
compared with a mill.
And, laftly, let it be noticed, that fuch a machine can
be ufed where no mill whatever can be put in motion.
A finall ftream of water, which wTould not move any
kind of wheel, will here raife one-third of its own quan¬
tity to the fame height 5 working as faft as it is fupplied.
For ail thefe reafons, wre think that the Hungarian
machine eminently deferves the attention of mathemati¬
cians and engineers, to bring it to its utmoft perfection-,
and into general ufe. 77iere are fituations wfflere this
kind of machine may be very ufeful. 7’hus, where the
tide rifes 17 feet, it may be ufed for compreffing air to
feven-eighths of its bulk j and a pipe leading from a
very large veflfel inverted in it, may be ufed for railing
the water from a veflfel of one-eighth of its capacity 17
feet high j or if this veflel has only -ytg- of the capacity
of the large one fet in the tide w ay, twro pipes may be led
from it, one intq.the fmall veflfel and the other into an equal
veflfel 16 feet higher, which receives the water from the
firft. Thus one-fixteenth of thew'ater may be raifed 34
feet, and a fmaller quantity to a Hill greater height; and
this wuth a kind of powTer that can hardly be applied in
any other w'ay. Machines of this kind are deferibed
by Schottus, Sturmius, Leupold, and other old w-riters;
and they fhould not be forgotten, becaufe opportunities
may
Plate C C C C XXHI .
1’ N !\ r Nt A ’r 1 c t?
■
V
PNEUMATIC S
Plate ccecxxiv
9,6
Plate rcc cxxvi.
' stf . 30.
<3J.
/f
, (//;>r// &Xt'r,. //«/. i SciJ/iter fiaf.
Cy-
\r
I’X Kl
XI A T I
C
/
Plate C C C C XX\ IT.
PNEUMATIC S
3^.
^ ■ & ^>-
*_fca/e o/ ’.//rvoA&i ■
/O // ^
7> /
>S$./S><?// . //«/. iJeu.//r&?'t fe^tr.
r Ifl'EX" MA-X ICS.
Plate CCCCXXV3I1
-4^ ?
1
CCCCXXLX .
'//Sr// v . //«/- /“//' >\ /*•**
PNEUMATIC S
Plate CCCtXXX 11
y/cutyitcrfc^tf
\Jt
y 97-
fcsiticii / A -B
£v£-£-
 L
PNEUMATIC S .
Plate CCCCXXXlll.
• Sbiti yt<z/.
PNEUMATICS.
751
Pneumatic may offer of making ikem highly ufeful. A gentleman’s
Engines. houfe the country may thus be fupplied with water
1'”T~'V ^ by a machine that will colt little, and hardly go out of
repair.
The lad pneumatical engine which we fliall fpeak of
at prefent is the common fanners, ufed for winnowing
grain, and for drawing air out of a room : and wre have
but few obfervations to make on them.
The wings of the fanners are inclofed in a cylinder
or drum, whofe circular fideshave a large opening BIDE
102 IO20 round the centre, to admit the air. By
turning the wings rapidly round, the air is hurried
round along with them, and thus acquires a centrifugal
tendency, by which it preffes ftrongly on the outer rim
of the drum : this is gradually detached from the circle
as at KI, and terminated in a trunk IHGF, wdtich goes
off in a tangential direction ; the air therefore is driven
along this paffage.
if the wings wrere difpofed in planes paffing through
the axis C, the compreition of the air by the anterior
furface wTould give it fome tendency to efcape in every
direftion, and would obftruft in fome degree the arrival Pneumatic
of more air through the fide-holes. They are therefore , £r|gmes-1
reclined a Jittle backward, as reprefented in the figure.
It may be fhown that their bell form would be that of a
hyperbolic fpiral a b c; but the llraight form approaches
fufficiently near to the mod perfect iliape.
Much labour is loft, howxver, in carrying the air
round thofe parts of the drum where it cannot efcape.
The fanners would either draw or difcharge almofl
twice as much air if an opening were made all round
one fide. This could be gradually contradled (where
required for winnowing) by a furrounding cone, and
thus direfted againft the falling grain : this has been
verified by affual trial. When ufed for drawing air out
of a room for ventilation, it wrould be much better to
remove the outer fide of the drum entirely, and let the
air lly freely off on all fides ; but the flat fides are ne-
ceffary, in order to prevent the air from arriving at the
fanners any other wray but through the central holes,
to w’hich trunks fliould be fitted leading to the apart¬
ment which is to be ventilated.
P o c
PNEUMATOSIS. See Medicine, N° 336.
PNEUMONIA. See Medicine, N° 183.
PNEUMONICS, in Pharmacy, medicines proper in
difeafes of the lungs, in which refpiration is affected.
PO, a large and celebrated river of Italy, which has
its fource at Mount Vifs in Piedmont, and on the con¬
fines of Dauphiny. It runs through Piedmont, Mont-
ferrat, the Milanefe, and duchy of Mantua j from thence
it runs to the borders of the Parmefan, and a part of
the Modenefe ; and having entered the Ferrarefe, it be¬
gins to divide at Ficheruolo, and proceeds to difcharge
itfelf into the gulf of Venice by four principal mouths.
As it paffes along, it receives feveral rivers, and often
overflow’s its banks, doing a great deal of mifehief; the
reafon of which is, that moft of thofe rivers defeend
from the Alps, and are increafed by the melting of the
fnow.
POA, Meadow-grass ; a genus of plants belonging
to the pentandria clafs, and in the natural method rank-
under the fourth order, Gramina. See Botany and
Agriculture Index.
POCHETTE See Barbatelli.
POCOCKE, Dr Edward, a learned oriental fcho-
lar, wTas the eldeft fon of the Rev. Edw’ard Pococke j
and was born at Oxford in 1604, where he was alfo
educated. In 1628 he w7as admitted probationer-fellow
■of his college, and about the fame time had prepared an
edition of the Second Epiftle of St Peter, the Second
and Third of St John, and that of St Jude, in Syriac
and Greek, with a Latin Tranflation and Notes. In
1629 he was ordained prieft, and appointed chaplain to
the Englifh merchants at Aleppo, where he continued
five or fix years; in which time he diftinguiflied himfelf
by his fortitude and zeal while the plague raged there.
At length returning to England, he was in 1636 ap¬
pointed reader of the Arabic leftures founded by Arch-
feifliop JAud. Three years after he went to Conftanti-
P o c
nople, w’here he profecuted his ftudies of the eaflern Poeocke.
tongues, and procured many valuable manuferipts. Af- —y——
ter near four years ftay in that city, he embarked in
1640 ; and taking Paris in his way, vifited Gabriel Sio-
nita the famous Maronite, and Hugo Grotius. In 1643
he wras prefented to the reftory of Childrey in Berks j
and about three years after married the daughter of
Thomas Burdett, Efq. About the middle of 1647 he
obtained the reftitution of the falary of his Arabic lec¬
ture, which had been detained from him about three
years. In 1648 King Charles I. who wras then prifoner
in the ifie of Wight, nominated Mr Pococke to the pro-
fefforfhip of Hebrew, and the canonry of Chrirt-church
annexed to it; but in 1650 he w7as ejefted from his ca¬
nonry for refufing to take the engagement, and foon
after a vote paffed for depriving him of his Hebrew and
Arabic lectures ; but feveral governors of houles, &c.
prefenting a petition in his favour, he was fuffered to
enjoy both thefe places. He had fome years before
publifiled his Specimen Hi/loricc Arabum ; and now ap¬
peared his Porta Mojis: and foon after the Englifh Po¬
lyglot edition of the Bible, to which he had largely
contributed, and alfo Eutychius’s Annals, with a Latin
verfion. At the Refioration, he was reftored to the
canonry of Chrift-church, and alfo received the degree
of doftor of divinity. He then publiflied his Arabic
verfion of Grotius’s Treatife of the Truth of the Chrif-
tidn Religion ; and an Arabic poem entitled Laimato /’
Ajam, with a Latin tranflation and notes. Soon after
he publilhed Gregory Abul Pharajius’s Hi/loria Dynaf-
tiarum. In 1674 he publifhed an Arabic verfion of the
chief parts of the Liturgy of the Church of England j
and a few years after his Commentary on the Prophecies
of Pvlicah, Malachi, Hofea, and Joel. This great man
died in 1691, after having been for many years con-
feffedly the firfl: perfon in Europe for eaftern learning ; ;
and was no lefs worthy of admiration for his uncommon .
modefty y
Pneumatofis
!!
Pococke.
POE
Fad •;a mod ily and humility, and all the virtues that can adorn,
,, Si a Chriftian. His-theological works were republifned at
, , London in 1740, in two volumes in folio.
PODAGRA, or the Gout. See Medicine, N°
.211.
PODALIRIUS, fon of /Efculapius and Epione,
was one of the pupils of the Centaur Chiron, under whom
he made himfelf fuch a mafter ot medicine, that during
the Trojan war the Greeks invited him to their camp to
itop a peililence which had baffled the ikill of ail their
. phyiicians. Some fuppofe, however, that he went to
the Trojan war, not in the capacity of a phyficianin the
.Grecian army, but as a warrior, attended by his brother
Machaon, in 30 fhips, with ipldiers from Qechalia,
Ithome, and Trica. At his return Ppdalirius was fflip-
wrecked on the coatl of Carla, where he cured of the
falling ficknefs a daughter of the king of the place. He
fixed his habitation there ; and built two towns, one of
which he called Si/rna, after his wife. The Carians, on
his death, built him a temple, and paid him divine
honours.
PODEX, in Anatomy, the fame with Anus.
PODGRAJE. See Asisia.
PODOLIA, a province of Poland, bounded on the
eaft by Volhinia and the river Ukrain ■, on the north and
north eaft, by Budfiac Tartary •, on the fouth-eaft, by
the river Niefter, which feparates it from Beffarabia and
Moldavia in European Turkey on the fouth-weft ; and
by the province of Red Ruffia on the north-weft. It
is ufually divided into the Upper and Lower. In the
Upper, which is the weftern part, the chief town is
Kamieck, the capital of Podolia, and of a palatinate.
In the Lower or eaftern part of Podolia the chief town
is Bracklaw, the capital of a palatinate.
PODOPHYLLUM, a genus of plants belonging
to the polyandria clafs} and in the natural method
ranking under the 27th order, Rhizcedce. See Botany
Index.
PODURA, or Springtail, a genus of infers of
the order of aptera. See Entomology Index.
POE-bird is an inhabitant of feme of the South fea
iflands, where it is held in great efteem and veneration
by the natives. It goes by the name of kogo in New
Zealand} but it is better known by that of poe-bird.
It is fomewhat lefs than our blackbird, and is remark¬
able for the fweetnefs of its note, as well as the beauty
•of its .plumage. Its tlefti is alfo delicate food.
POECILE was a famous portico at Athens, which
received its name from the variety (VoucjAos) of paintings
which it contained. Zeno kept his fchool there ; and
there alfo the ftoics received their leffons, whence their
name, a root, a porch. The Poecile was adorned, among
many others, with a piflure of the fiege and hacking of
Troy, the battle of The feus againft the Amazons, and
the fight between the Lacedoemonians and Athenians at
Oenoe in Argolis. The only reward which Miltiades
obtained after the battle of Marathon was to have his
picture drawn more confpicuous than that of the reft of
the officers that fought with him, in the reprefentation
which was made of the engagement, and which was
hung up in the Poecile in commemoration of that cele¬
brated viflory.
POEM, a poetical compofition. See Poetry.
POESTUM. or Posidonia, an ancient c’ty of
Grecia Magna, now part of the kingdom of Naples.
POE
It was founded by one of thofe colonies Lorn Greece PaA-im.
which in the early ages eitabliihed themfelves in Italy •,
and it flouriihed before the foundation of Home it left.
It was deftroyed by the Goths on the decline of the
Roman empire, who in their barbarous zeal for the
Chriftian religion overturned every place of Pagan wor-
fhip which was expo fed to their ravages. Since that
time it has been in ruins ; and thefe ruins were unknown
till they were difeovered in the following manner: “ In
the year 1 7 ^5 (fays the author of the Antiquities, Hi~
ft on/, and Views of V of uni), an apprentice to a painter
at Naples, who was on a vifit to his friends at Capaccio,
by accident took a walk to the mountains which fur-
round the territory of Poeftum. The only habitation
he perceived was the cottage of a farmer, who cultivated
the beft part of the ground, and referved the reft for
pafture. The ruins of the ancient city made a part of
this view, and particularly ftruck the eyes of the young
painter : who, approaching nearer, faw with allonilh-
rnent walls, towers, gates and temples. Upon his re¬
turn to Capaccio, he confulted the neighbouring people
about the origin of thefe monuments of antiquity. He
could only learn, that this part of the country had been
uncultivated and abandoned during their memory 5 that
about ten years before, the farmer, whole habitation he
had noticed, eftablifhed himfelf there 3 and that having
dug in many places and fearched among the ruins that
lay round him, he had found treafures fuibcient to enable
him to purchafe the whole. At the painter’s return
to Naples, he informed his rn._2.cr of thefe particulars, „
whofe curiofity was fo greatly excited hy the d. fcriplion,
that he took a journey to the place, and made drawings
of the principal views. Thefe were fhown to the king
of Naples, who ordered the ruins to be cleared, and
Poeftura arofe from the obfeurity in which it had re¬
mained for upwards of 700 years, as little known to the
neighbouring inhabitants as to travellers.”
Our author gives the following defeription of it in
its prefent ftate. It is, fays he, of an oblong figure,
about two miles and a half in circumference. It has
four gates, which are oppofite to each other. On the
key -ftone of the arch of the north gate, on the outfide,
is the figure of Neptune in balfo relievo, and within a
hippocampus. The walls which ftill remain are com-
pofed of very large cubical ftones, and are extremely
thick, in fome parts 18 feet. That the walls have re¬
mained unto this time is owing to the very exact manner
in which the ftones are fitted to one another (a circum-
ftance obferved univerfally in the mafonry of the an¬
cients), and perhaps in fome meafure to a ftaladllcal
concretion which has grown over them. On the walls
here and there are placed towers of different heights 3
thofe near the gates being much higher and larger than
the others, and evidently of modern workmanthip. He
oblerves, that, from its fituation among marfhes, bitu¬
minous and fulphureous fprings, Poeftum muft have been
umvholefome 3 a circumftance mentioned by Strabo,
Morbofam earn facit fuvuts in paludes diffufus. In fuch
a fituation the water muft have been bad. Hence the
inhabitants were obliged to convey that neceffary of life
from purer fprings by means of aqueducts, ofv which
many veftiges ftill remain.
The principal monuments of antiquity are a theatre,
an amphitheatre, and three temples. The theatre and
amphitheatre are much ruined. The fir ft temple is
hexaftylcs,
[ 752 1
POE [ 753 ] POE
Pceftum. hexaftylos, and amphiproftylos. At one end, the pi-
-v  lafters and two columns which divided the cella from
the pronaos are ftill remaining. Within the cella are
two rows of fmaller columns, with an architrave, which
fupport the fecond order. This temple our author takes
to be of that kind called by Vitruvius hyphczthros, and
fupports his opinion by a quotation from that author.
The fecond temple is alfo amphiproltylos : it has nine
columns in front and 18 in flank, and feems to be of that
kind called by Vitruvius pfeudodipteros. The third is
likewife amphiproltylos. It has fix columns in front and
13 in flank. Vitruvius calls this kind of temple pen-
pteros. “ The columns of thefe temples (fays our au¬
thor) are of that kind of Doric order which we find em¬
ployed in works of the greateft antiquity. They are
hardly five diameters in height. They are without bafes,
which alfo has been urged as a proof of their antiquity j
but we do not find that the ancients ever ufed bafes to
this order, at leaft till very late. Vitruvius makes no
POE
AMIDST thofe thick clouds which envelope the
firft ages of the world, reafon and hiltory throw
fome lights on the origin and primitive employment of
this divine art. Reafon fuggefts, that before the inven¬
tion of letters, all the people of the earth had no other
1 method of tranfmitting to their defcendants the prin-
Ongin of cjpjes Gf their worfliip, their religious ceremonies, their
-Poetiy- laws, and the renowned aflions of their fages and heroes,
than by poetry j which included all thefe objects in a
kind of hymns that fathers fung to their children, in
order to engrave them with indelible ftrokes in their
hearts. Hiflory not only informs us, that Mofes and
Miriam, the firft authors that are known to mankind,
fung, on the borders of the Red fea, a fong of divine
praife, to celebrate the deliverance which the Almighty
had vouchfafed to the people of Ifrael, by opening a paf-
fage to them through the waters ; but it has alfo tranf-
mrtted to us the fong itfelf, which is at once the moft
ancient monument and a mafterpiece of poetic compo-
fition.
The Greeks, a people the moft ingenious, the moft
- mnimated, and in every fenfe the moft accomplilhed, that
the world ever produced—ftrove to ravifli from the He¬
brews the precious gift of poetry, which was vouchfafed
them by the Supreme Author of all nature, that they
might afcribe it to their falfe deities. According to
their ingenious fi&ions, Apollo became the god of poe¬
try, and dwelt on the hills of Phocis, Parnaflus, and
Helicon, whofe feet were waflied by the waters of Hip-
pocrene, of which each mortal that ever drank was
feized with a facred delirium. The immortal fwans
floated on its waves. Apollo was accompanied by the
Mufes—thofe nine learned lifters—the daughters of
Memory : and he was conftantly attended by the Graces.
Pegafus, his winged courfer, tranfported him with a ra¬
pid flight into all the regions of the univerfe. Happy
emblems ! by which we at this day embellilh our poe¬
try, as no one has ever yet been able to invent more bril¬
liant images.
The literary annals of all nations afford veftiges of
Vol. XVI. Part II.
mention of bafes for this order : and the only inftance we Ecefl am,
have of it is in the firft order of the Colifaeum at Rome,, 1J()eU
which was built by Vefpalian. The pillars of thefe
temples are fluted with very (hallow flutings in the man¬
ner defcribed by Vitruvius. The columns diminilh from
the bottom, which was the moft ancient method almoft
univerfally in all the orders. The columns have aftra-
gals of a very lingular form ; which Ihows the error of
thofe who imagine that this member was firft invented
with the Ionic order, to which the Greeks gave an aftra-
gal, and that the Romans were the firft who applied it to
the Doric. The echinus of the Capitol is of the fame
form with that of the temple of Corinth defcribed by
Le Roy.” See Swinburne's Travels in the Two Sici¬
lies, vol. ii. p. 131—140.
POET, the author of a poem. See the article
Poetry.
Provenpal Poets. See Troubadours.
TRY.
poetry from the remoteft ages. They are found among
the moft favage of the ancient barbarians, and the moft
defolate of all the Americans. Nature afferts her rights
in every country and every age. Tacitus mentions
the verfes and the hymns of the Germans, at the time
when that rough people yet inhabited the woods, and
while their manners were ftill favage. The firft inha¬
bitants of Runnia and the other northern countries,
thofe of Gaul, Albion, Iberia, Aufonia, and other na¬
tions of Europe, had their poetry, as well as the an¬
cient people of Afia, and of the known borders of A-
frica. But the fimple produ&ions of nature have con¬
ftantly fomething unformed, rough, and favage. The
Divine Wifdom appears to have placed the ingenious
and polifhed part of mankind on the earth, in order to
refine that which comes from her bofom rude and im-
perfeft : and thus art has polilhed poetry, which iflued
quite naked and favage from the brains of the firft of
mankind. _ 2
But what is Poetry? It would be to abridge the Definition
limits of the poetic empire, to contract the fphere of of poetry,
this divine art, Ihould we fay, in imitation of all the
dictionaries and other treatiles on verlification, lhat
poetry is the art of making verfes, of lines or periods that
are in rhyme or metre. This is rather a grammatical
explanation of the word, than a real definition of the
thing, and it wmuld be to degrade poetry thus to de¬
fine it. The father of criticilm has denominated poe¬
try f’Ctptiflati], an imitative art .* but this, though
juft in itfelf, is too general for a definition, as it does
not difcriminate poetry from other arts which depend
equally on imitation. The jufteft definition feems to
be that given by Baron Bielfield *, That poetry is the*Elem.of
art of expreffing our thoughts by fiBion. In fa ft, it is af- Univ.Erud.
ter this manner (if we refle£l with attention) that all
the metaphors and allegories, all the various kinds of
fi&ion, form the firft materials of a poetic edifice: it
is thus that all images, all comparifons, allufions, and
figures, efpecially thofe which perfonify moral fubjecfts,
as virtues and vices, concur to the decoration of fuch a
3 C ftruftuxe.
754-
4
EfTence of
poetry.
POE
ftru&ure. A work, tlierefore, that is filled with in¬
vention, that iucefianrly prefents images which render
tiie reader attentive and affected, where the author gives
interefling fentiments to every thing that he makes fpeak,
and where he makes fpeak by fenfible figures all thofe
objects which would affect the mind but weakly when
clothed in a ffmple profaic .ftyle, fuch a work is a poem.
While that, though it be in verfe, which is of a didabtic,
dogmatic, or moral nature, and where the objects are
prefented in a manner quite fxmple, without fiflion,
without images or ornaments, cannot be called poetry,
but merely a work in verfe} for the art of reducing
thoughts, maxims, and periods, into rhyme or metre, is
very different from the art of poetry.
An ingenious fable, a lively and intereffing romance,
a comedy, the fublime narrative of the actions of a hero,
fuch as the Telemachus of M. Fenelon, though written
in profe, but in meafured profe, is therefore a work of
poetry : becaufe the foundation and the fuperftrufture
are the produftions of genius, as the whole proceeds
from fiflion 5 and truth itfelf appears to have employed
an innocent and agreeable deception to inftru£t with ef¬
ficacy. This is fo true, that the pencil alfo, in order to
pleafe and affeft, has recourfe to fiction p and this part
of painting is called the poetic compojition of a pi Bure. It
is therefore by the aid of fiftion that poetry, fo to fpeak,
paints its expreffions, that it gives a body and a mind
to its thoughts, that it animates and exalts that which
would otherwife have remained arid and infenfible. It
is the peculiar privilege of poetry to exalt inanimate
things into animals, and abftraft ideas into perfons.
The former licence is fo common, that it is now con-
fidered as nothing more than a characleriftical dialeft
appropriated by the poets to diftinguiih themfelves from
the writers of profe ; and it is at the fame time fo effen-
tial, that we queftion much if this fpecies of compofi-
T R Y.
tion could fubfift without it : for it will perhaps, upon
examination, be found, that in every poetical defcription
feme of the qualities of Animal Nature are aferibed la
things not having life. Every work, therefore, where
the thoughts are exprefled by fictions or images, is po¬
etic •, and every work where they are exprefl'ed natui al¬
ly, limply, and without ornament, although it be in
verfe, is profaic.
Verfe, however, is not to be regarded as foreign or
faperliuous to poetry. To reduce thofe images, thofe
fictions, into verfe, is one of the greateft difficulties in
poetry, and one of the greateft merits in a poem : and
for thefe reafons, the cadence, the harmony of founds,
particularly that of rhyme, delight the ear to a high
degree, and the mind infenfibly repeats them while the
eye reads them. There refults therefore a pleafure to
the mind, and a ftrong attachment to thefe ornaments :
but this pleafure would be frivolous, and even childilb,
if it were not attended by a real utility. Verfes were f
invented in the firft ages of the world, merely to aid ^ough not
and to ftrengthen the memory : for cadence, harmony, effbnual to
and efpecially rhyme, afford the greateft afliftance to poetry, one
the memory that art can invent j and the images, 01* of its ex-
poetic fiflions, that ftrike our fenfes, aflift in gravingcellencie%
them with fuch deep traces in our minds, as even time
itfelf frequently cannot efface. How many excellent
apophthegms, fentences, maxims, and precepts, would
have been buried in the abyfs of oblivion, if poetry had
not preferved them by its harmony ? To give more
efficacy to this lively impreflion, the firff poets fung
their verfes, and the words and phrafes muff necefiarily
have been reduced, at leait to cadence, or they could
not have been fufceptible of mufical expreflion. One
of the great excellencies, therefore, though not a ne-
ceffary conftituent of poetry, confifts in its being ex-
preffed in verfe. See Part HE
Part I. GENERAL PRINCIPLES of the ART.
Sect. I. Of the Ejjence and End of Poetry.
THE offence of Polite Arts in general, and confe-
quently of poetry in particular, confifts in exprcffion ;
and we think that, to be poetic, the expreftion muff
neceflarily arife from fiBion, or invention. (See the ar¬
ticle Art, particularly from N° 1 2. to the end.) This in¬
vention, which is the fruit of happy genius alone, arifes,
1. From the fubjeft itfelf of which we undertake to
treat: 2. From the manner in which we treat that fub-
je<ft, or the fpecies of writing of which we make ufe :
3. From the plan that we propofe to follow7 in conformi¬
ty to this manner 5 and, 4. From the method of exe¬
cuting this plan in its full detail. Our firff guides, the
ancients, afford us no lights that can elucidate all thefe
objects in general. The precepts which Ariftotle lays
down, relate to epic and dramatic poetry only: and
which, by the way, confirms our idea, that antiquity
itfelf made the eflenee of poetry to confift in fiflion, and
not in that fpecies of verfe which is deftitute of it, or in
that which is not capable of it. But fince this art has
rifen to a great degree of perfe&ion 5 and as poetry,
like electricity, communicates its fire to every thing it
touches, and animates and embelllihes whatever it treats;
there feems to be no fubjeft in the univerfe to which
poetry cannot be applied, and which it cannot render
equally brilliant and pleafing. From this univerfality
of poetry, from its peculiar property of expreftion by
fiction, which is applicable to all fubjeCrs, have arifen
its different fpecies, of which a particular defcription
w7ill be given in the fecond part.
Horace, in a well-known verfe, has been fuppofed to
declare the end of poetry to be twofold, to pleafe, or to
inftruCI:
Antprodeffe volant, aut deleBare poetce.
But Dr Beattie * maintains, that the ultimate end of End of
this art is to pleafe 5 inttruftion being only one of the poetry,
means-(and not always a neceflary one) by which that *EJays or?
ultimate end is to be accomplhhed. The paffage rightly
underftood, he obferves, will not appear to contain any czn il
thing inconfiftent with this do&rine. The author is chap. i.
there Hating.a comparifon between the Greek and Ro¬
man writers, with a view to the poetry of the ftage; and,
after commending the former for their correftnefs, and
for the liberal fpirit wherewith they conduced their
literary labours, and blaming his countrymen for their
inaccuracy
Part 1.
POETRY.
Poetry.
\ Hor. Ar.
Poet. 333
—347-
Eirence and inaccuracy and avarice, lie proceeds tlms : “ 1 he ends
End of propofed by our dramatic poets (or by poets itv ge¬
neral) are, *to pleafe, to inftruft, or to do both. When
inftru&ion is your aim, let your moral fentences be
expreffed with brevity, that they may be readily un-
derftood, and long remembered : where you mean to
pleafe, let your fiftions be conformable to. truth or
probability. ‘ The elder part of your audience (or
readers) have no relifh for poems that give pleafure only
without inftruaion ; nor the younger for fuch writings
as give inftru&ion without pleafure. He only can fe-
cure the univerfal fuflfrage in his favour, who blends
the ufeful with the agreeable, and delights at the fame
time that he inftruas the reader. Such are the works
that bring money to the bookfeller, that pals into fo¬
reign countries, and perpetuate the author’s name
through a long fucceffion of ages f—Now, what is
the meaning of all this ? What, but that to theperfeBion
of dramatic poetry (or, if you pleafe, of poetry in ge¬
neral) both found morals and beautiful fiftion are re-
quifite ? But Horace never meant to fay, that inftruc-
tion, as well as pleafure, is neceffary to give to any
compofition the poetical character ; or he would not. in
another place have celebrated with fo much affection
and rapture the melting Itr&ins of Sappho, and the
playful genius of Anacreon J,—two authors tranfeen-
IbTv.odeo^entiy fweet, but not remarkably inftruftive. We are
fure, that pathos, and harmony, and elevated language^
5 Hor. Sat. were, in Horace’s opinion, effential to poetry § 5 and
hb. i. fat. 4. of thefe decorations nobody will affirm, that inftruction
ver. 40. is end, who conliders that the molt inltrudtive books
in the world are written in plain profe.
In ffiort, our author has endeavoured by many inge¬
nious arguments and illuftrations to eftabliffi it as a
truth in criticifm, that the end . of poetry is to pleafe.
Verfes, if pleafing, may be poetical, though they con¬
vey little or no inftruftion •, but verfes, whole foie merit
it is that they convey inftru&ion, are not poetical. In¬
ftruaion, however, he admits, efpecially in poems of
length, is neceffary to their perfeBion, becaufe they
would not be perfeBhj agreeable without it.
Sect. II. Of the Standard of Poetical Invention.
Poetical Homer’s beautiful defeription of the heavens and
invention earth, as they appear in a calm evening by the light of
to be regu- m0on and ftars, concludes wdth this circumftance,
lated ,( Ancl ^g heart 0f the ffiepherd is glad*.” Madame
*f/ai,V;11'Dacier, from the turn ffie gives to the paffage in her
verfion, feems to think, and Pope, in order perhaps to
make out his couplet, infinuates, that the gladnels of
the Ihepherd is owing, to his fenfe of the utility of thofe
luminaries. And this may in part be the cafe : but
this is not in Homer ; nor is it a neceffary confideration.
It is true, that, in contemplating the material, univerfe,
they who’ difeern the caufes and effeas of things muft
Seattle's be more rapturoudy entertained than thofe who perceive
Etfays, nothing but ftiape and fize, colour and motion. Yet,
in the mere outfide of Nature’s work, there is a.fplendor
Part i.
rhap. a.
and a magnificence to which even untutored minds can¬
not attend without great delight.
Not that all peafants or all philofophers are equally
fufceptible of thefe charming impreffions. It is ftrange
to obferve the calloufnefs of fome men, before whom all
the glories of heaven and earth pa!s in daily fucceffion*
without touching their hearts, elevating their fancy, 6r
leaving any durable remembrance. Even of thole who ^
pretend to fallibility, how many are there to whom the
luftre of the riling or felting filn ; the fparkling concave
of the midnight-Iky ; the mountain-foreft toffing and
roaring to the ftorm, or warbling with all the melodies
of a fummer-eveiling ; the fweet interchange of hill and
dale, ffiade and funffiine, grove, lawm, and water, which
an extenlive landfcape ofl'ers to the viewT •, the feenery
of the ocean, fo lovely, fo majeftic, and fo tremendous •,
and the many pleafing varieties of the animal and vege¬
table kingdoms, could never afford fo much real fatisfac-
tion, as the fteams and noife of a ball-room, the. infipid
fiddling and fqueaking of an opera, or the vexations and
wranglings of a card-table !
But fome minds there are of a different make; wffio,
even in the early part of life, receive from the contem¬
plation of Nature a fpecies of delight which they would
hardly exchange for any other, and who, as avarice and
ambition are not the infirmities of that period, would,
with equal fincerity and rapture, exclaim,
I care not, Fortune, what you me deny ;
You cannot rob me of free Nature’s grace ;
You cannot (hut the windows of the Iky,
Through which Aurora {hows her bright’ning face j
You cannot bar my conftant feet to trace
The woods and lawns by living ftreani at eve.
Caflle of Indolence.
Such minds have always in them the feeds of true tafte,
and frequently of imitative genius. At leaft, though
their enthufiaftic or vifionary turn of mind (as the man
of the world would call it) ffiould not always incline
them to prattife poetry or painting, we need not fcruple
to affirm, that without fome portion of this enthufiafm
no perfon ever became a true poet or painter, for he
wffio would imitate the works of nature, aiuft. firft. ac¬
curately obferve them •, and accurate obfervation is to
be expedted from thofe only wffio take great pleafuie in
To a mind thus difpofed no part of creation is indif¬
ferent. In the crowded city and howling wildernefs ;
in the cultivated province and folitary ifle *, in the
flowery lawn and craggy mountain •, in the murmur of
the rivulet and in the uproar of the ocean ; in the ra¬
diance of fummer and gloom of winter ; in the thunder
of heaven and in the whifper of the breeze } he ftill
finds fomething to rouze or to foothe his imagination,
to draw forth his affedtions, or to employ his u.nder-
ftanding. And from every mental energy that is not
attended with pain, and even from fome of thofe that
are, as moderate terror and pity, a found mind derives
fatisfadlion •, exercife being equally neceffary to the body
and the foul, and to both equally produdlive of health
and pleafure.
This happy fenfibility to the beauties of nature fliould
be cheriffied in young perfons. It engages them to
contemplate the Creator in his wonderful works •, it pu¬
rifies and harmonizes the foul, and prepares it for moral
and intelleftual difcipline’; it fupplies an endlefs fourefi
of amufement; it contributes even to bodily health :
and, as a ftridt analogy fubfiftsffietween material and mo¬
ral beauty, it leads the heart by an eafy tranfit.ion from
the one to the other-, and thus - recommends virtue for
its tranfeendant lovelivefe, and makes vice appear the
5 C 2 objedl
7S<5 POE
r, ,/f • object of contempt and abomination. An intimate ac-
_ /f ntii,.n.^ quaintance defcriptive poets, Spenfer, Mil-
ton, and Thomfon, but above all with the divine Geor¬
gia, joined to fome practice in the art of drawing, will
promote this amiable fenfibility in early years : for then
the face of nature has novelty fuperadded to its other
charms, the paffions are not pre-engaged, the heart
is free from care, and the imagination warm and ro-
7 mantic.
it arid a rd of not to longer on thofe ardent emotions that
mature. are Pecubar to the enthufiaftic difciple of nature, may it
not be affirmed of all men, without exception, or at
leaf!: of all the enlightened part of mankind, that they
are gratified by the contemplation of things natural, as
op poled to unnatural ? Monftrous lights pleafe but for
a moment, if they pleafe at all j for they derive their
^ ? charm from the beholder’s amazement, which is quickly
Tour S over* We read indeed of a man of rank in Sicily*,
cily, let. 24. w^° cboofes to adorn his villa with piffures and llatues
. of moft unnatural deformity : but it is a lingular in-
llance ; and one would not be much more furprifed to
hear of a perfon living without food, or growing fat by
the ufe of poifon. To fay of any thing, that it is
contrary to nature, denotes cenfure and dil'guft on the
part of the fpeaker } as the epithet natural intimates an
agreeable quality, and feems for the moft part to imply,
that a thing is as it ought to be, fuitable to our own
tafte, and congenial with our own conftituiion. Think
with what fentiments we ftiould perufe a poem, in which
nature was totally mifreprefented, and principles of
thought and of operation fuppofed to take place, re¬
pugnant to every thing we had feen or heard of:—in
which, for example, avarice and coldnefs were afcribed
to youth, and prodigality and paffionate attachment to
the old } in which men were made to aft at random,
, fometimes according to chara&er, and fometimes con¬
trary to it 5 in which cruelty and envy were produ&ive
of love, and beneficence and kind affe&ion of hatred :
in which beauty was invariably the objeft of diflike, and
uglinefs of defire j in which fociety was rendered happy
by atheifm and the promifcuous perpetration of crimes,
and juftice and fortitude were held in univerfal contempt.
Or think, how we fhould relifh a painting, where no
regard was had to the proportions, colours, or any of
the phylical laws, of Nature where the ears and eyes
of animals were placed in their fhoulders j where the
Iky was green and the grafs crimfon 5 where trees grew
with their branches in the earth and their roots in the
air ; where men were feen fighting after their heads were
cut off, {hips failing on the land, lions entangled in cob¬
webs, Iheep preying on dead carcafes, fifties fporting in
the woods, and elephants walking on the fea. Could
fuch figures and combinations give pleafure, or merit the
appellation of fublime or beautiful ? Should we hefitate
to pronounce their author mad ? And are the abfurdities
of madmen proper fubjecfts either of amufement or of imi¬
tation to reafonable beings ?
Let it be remarked, too, that though we diftinguilh
our internal powers by different names, becaufe other-
wife we could not fpeak of them fo as to be underftood,
they are all but fo many energies of the fame individual
mind j and therefore it is not to be fuppofed, that what
contradi&s any one leading faculty lliould yield perma-
fient delight to the reft. That cannot be agreeable to
jeafon, which confcience difapproves j nor can that gra-
T R Y • Parti.
tify imagination, which is repugnant to reafon. Be- Of
fides, belief and acquieicence of mind are plealant, as Invention,
diftruft and difbelief are painful : and therefore, that
only can give folid and general fatisfatlion, which has
fomething of plaufibility in it } fomething which we
conceive it poflible for a rational being to believe. But
no rational being can acquiefce in what is obvioufly con¬
trary to nature, or implies palpable abfurdity.
Poetry, therefore, and indeed every art whofe end is
to pleale, muft be natural; and if fo, muft exhibit real
matter of fadt, or fomething like it 5 that is, in other
words, muft be either according to truth or according
to verifimilitude.
And though every part of the material univerfe
abounds in objedls of pleafurable contemplation, yet no¬
thing in nature fo powerfully touches our hearts, or gives
fo great variety of exercife to our moral and intellectual
faculties, as man. Human affairs and human feelings are.
univerfally interefting. There are many who have no-
great relilh for the poetry that delineates only irrational
or inanimate beings j but to that which exhibits the
fortunes, the charadters, and the condudt of me-n, there
is hardly any perfon who does not liften with fympathy
and delight. And hence to imitate human action, is
confidered by Ariftotle as effential to this art; and muft
be allowed to be effential to the moft pleafing and moft
inftrudtive part of it, Epic and Dramatic compolition.
Mere deferiptions, however beautiful, and moral reflec¬
tions, however juft, become tirefome, where our paffions
are not occafionally awakened by fome event that con¬
cerns our fellow-men. Do not all readers of tafte re¬
ceive peculiar pleafure from thofe little tales or epifodes-
wi th which Thomfon’s deferiptive poem on the Seafons
is here and there enlivened? and are they not fenfible,.
that the thunder-ftorm would not have been half fo in¬
terefting without the tale of the two lovers (Summ. v.
1171) ; nor the harveft-feene, without that of Palemon
and Lavinia {Aut. v. 177.) j nor the driving fnows,
without that exquifite pidiure of a man perilhing among
them {Winter, v. 276.) ? It is much to be regretted,
that Young did not employ the fame artifice to animate
his Night-Thoughts. Sentiments and deferiptions may
be regarded as the pilafters, carvings, gildings, and
other decorations of the poetical fabric : but human ac¬
tions are the columns and the rafters that give it lia¬
bility and elevation. Or, changing the metaphor, we
may conlxder thefe as the foul which informs the lovely
frame ; while thofe are little more than the ornaments
of the body.
Whether the pleafure we take in things natural, and
our diflike to what is the reverfe, be the effecl of habit
or of conftitution, is not a material inquiry. There is
nothing abfurd in fuppofing, that between the foul, in
its firft formation, and the reft of nature, a mutual har¬
mony and fympatby may have been eftablilhed, which
experience may indeed confirm, but no perverfe habits g
could entirely fubdue. As no fort of education could j^bj,. [ia3
make man believe the contrary of a felf-evident axiom, great in-
or reconcile him to a life of perfedt folitude , fo we Auence
Ihould imagine, that our love of nature and regularity ^rer^ent|"
might ftill remain with us in fome degree, though we had feejjng an4
been born and bred in the Sicilian villa above-mentioned, of courfe
and never heard any thing applauded but what deferved upon
cenfure, nor cenfured but what merited applaufe. YetP0etr3r‘
habit muft be allowed to have a powerful influence over
the
No necef-
fity that
the poet
fhou'd ex¬
actly copy
nature.
part I. P O E
Of the fervtiments and feelings of mankind ; for objects to
invention, which v/e have been long accuftomed, tve are apt to con-
v*“ v  tract a fondnefs : we conceive them readily, and contem¬
plate them with pleafure j nor do we quit our old tracts
of {peculation or practice without reluctance and pain.
Hence in part arifes our attachment to our own profef-
ftons, our old acquaintance, our native foil, our homes,
and to the very hills, dreams, and rocks in our neigh¬
bourhood. It would therefore be ftrange, if man, accu-
tfomed as he is from his earlielt days to the regularity of
nature, did not contraft a liking to her productions and
principles of operation.
Yet we neither expeCt nor defire, that every human
invention, where the end is only to pleale, fliould be an
exaCt tranfcript of real exiftence. It is enough, that the
mind acquiefce in it as probable or plaufible, or iuch as
we think might happen without any direct oppofition to
the laws of nature :—Or, to fpeak more accuratel), it is
enough that it be confiftent, either, firlt, with general
experience j or, fecondly, with popular opinion j o.,
thirdly, that it be confident with itfelf, and conneCted
with probable circumdances.
Fhft : If a human invention be confident vnl\\general
experience, wre acquiefce in it as fudiciently probable.
Particular experiences, however, there may be, fo un¬
common, and lo little expeCted, that we fhould not ad¬
mit their probability, it we did not know them to be
true. No man of fenfe believes, that he has any likeli¬
hood of being enriched by the difcovery of hidden trea-
fure j or thinks it probable, on purchafing a lottery-
ticket, that be (hall gain the firft prize ; and yet great
wealth has actually been acquired by fuch good fortune.
But we diould look upon tbefe as poor expedients in a
play or romance for bringing about a happy catadiophe.
We expeft that fiClion Ihould be more confonant to the
general tenor of human affairs •, in a word, that not pof-
fibility, but probability, ftiould be the ftandard oi poeti¬
cal invention.
Firticn fu£ Secondly : Fiaion is admitted as conformable to this
ficiently dandard, when it accords with received opinions. Thefe
conform- may be erroneous, but are not often apparently repug-
able 10 naut to natnre. On this account, and becaufe they are
wherTit ac familiar to us from our infancy, the mind readily ac¬
cords with quiefces in them, or at lead yields them that degree of
' ’ credit which is neceflfary to render them pleafing : hence
the fairies, ghods, and witches of Shakefpeare, are ad¬
mitted as probable beings ; and angels obtain a place in
religious pictures though we know that they do not now
appear in the fcenery of real life. A poet who diould at
this day make the whole adion of his tragedy depend
upon enchantment, and produce the cnief events by the
adidance of fupematural agents, would indeed be cenfur-
ed as tranfgreding the bounds of probability, bebanifhed
from the theatre to the nurfery, and condemned to write
fairy tales indead of tragedies. But Shakefpeare was in
no danger of fuch cenfures; In his daj s the dotffrine ot
witchcraft was edablilhed both by law and by. the fa-
fhion j and it was not only unpolite, out criminal, to
received
opinions,
TRY.
doubt it. Now indeed it is admitted only by the vul- ^
gar ; but it does not therefore follow that an old poem ^
built upon it Ihould not be acceptable to the learned
themfelves. When a popular opinion has long been ex¬
ploded, and has become repugnant to philofophical be¬
lief, the fictions built upon it are dill admitted as natu¬
ral, both becaule we ail remember to have lidened o
them in childhood with foroe degree of cteoit, and be¬
caufe we know that they were accounted, natural by the
peoole to whom they were fird addrefieu. j whofe ienti-
ments and views of things we are willing to adopt, when,
by the power of pleaffng deicription, we are introduced
into their fcenes, and made acquainted with tneir man¬
ners. Hence we admit the theology of the ancient poets,
their Elviium and Tartarus, Scylla and Charybdis, Cy¬
clops and Circe, and the red of thole “ beautiful won¬
ders” (as Horace calls them) which were believed in „
the heroic ages j as well as the demons and enchantine.icS
of Taffo, which may be fuppofed to have obtained no
imall degree of credit among the Italians of the 16th
century, and are fuitable enough to the notions that pre¬
vailed univerfally in Europe not long before (a). . In
fa&, when poetry is in other refpe&s true, when it gives
an accurate difplay of thofe parts of nature about which
we know that men in all ages mud have entertained the
fame opinion, namely, thole appearances in the vilible
creation, and thofe feelings and working of the hi.om.n
mind, which are obvious to all mankind j—tvhen poetry
is thus far according to nature, we are very willing to
be indulgent to what is fiaitious in it, and to grant a
temporary allowance to any lydem of fable w hich the
author pleales to adopt j provided that he lay the Icene
in a didant country, or fix the date to a remote period.
This is no unreafonable piece of complaifance j we owe
it both to the poet and to ourfelves } for without it we
Ihould neither form a right eftimate of his genius, nor re¬
ceive from his works that pleafure which they were in¬
tended to impart. Let him, however, take care, that
his fydem of fable be fuch as his countrymen and cotem¬
poraries (to whom his work is immediately addrefied)
might be fuppofed capable of yielding their .aifent to ^
for otherwife we ihould not believe him to be in earneft :
and let him conned it as much as he can with probable
circumftances, and make it appear in a feries of events
confident with itfelf. .
For (thirdly) if this be the cafe, we lhall admit his
dory as probable, or at lead as natural, and conlequentiy
be intereded in it, even though it be not warranted by
o-eneral experience, and derive but dender authoritv from
popular opinion. Calyban, in the lemped, would have
diocked the mind as an improbability, if we had not been
made acquainted with his origin, and feen his charactei
difplayed in a feries of confident behaviour. But when
we are told that he fprung from a witch and a demon, a
conned ion not contrary to the Hws of nature, as they
were underdood in Shakefpeare's time, and find his
manners conformable to his defcent, we are eafily recon¬
ciled to the fidion. In the fame fenfe, the Lilliputians
of
CO In the Idth century, the common people of Italy believed that the poet Dante went down to hell; that
the inferno was a true account of what he Taw there; andjhat his fo much of
Flic infer nu w a.-> a liuv-    — — - , N i r
feemed by its growth and colour to have been too near the fire), were the conic'
his time in that hot and fmoky region. See Vicende della Literature do %• L -
'mna. cap. 4.
758 POE
Of o'f Swift may pafs for probable beings ; not fo much be-
'Invcnuon. caufe we know a belief in pigmies was once current
Ir in the world (for the true ancient pigmy was at 1 call
and is thrice as tall as thole whom Gulliver vifited), but te-
confiftent caufe we find that every circumftance relating to them
with itlelf. accords with itfelf, and vith their fuppofed charafter.
It is not the fize of the people only that is diminutive j
iheir country, feas, {hips, and towns, are all in exadl
proportion j their theological and political principles,
their paffions, manners, cuftoms, and all the parts of
their conduft, betray a levity and littlenefs perfeSlly
fuitable ; and fo fimple is the whole narration, and ap¬
parently fo artlefs and fincere, that we fhould not much
Beattie s wonder if it had impofed (as we have been told it has)
utfupra uPon f°mt: perfons of no contemptible underftanding.
The fame degree of credit may perhaps for the fame rea-
fons be due to his giants. But when he grounds his
narrative upon a contradi&ion to nature 5 when he pre-
fents us with rational brutes, and irrational men 5 when
he tells us of horfes building houfes for habitation, milk¬
ing cows for iood, riding in carriages, and holding con-
verfations on the laws and politics of Europe 5 not all
his genius (and he there exerts it to the utmoft) is able
to reconcile us to fo monftrous a fiftion : we may fmile
at fome of his abfurd exaggerations j we may be pleafed
with the energy of llyle, and accuracy of defeription,
in particular places j and a malevolent heart may triumph
in the fatire 5 but we can never relifli it as a fable, be-
caufe it is at once unnatural and felf-contradiftory.
Swift’s judgement leems to have forfaken him on this oc-
cafion : he wallows in naflinefs and brutality : and the
general run ot his fatire is downright defamation. Lu¬
cian’s True Hijlory, is a heap of extravagancies put to¬
gether without order or unity, or any other apparent
defign than to ridicule the language and manner of grave
authors. His ravings, which have no better right to
the name of fable, than a hill of rubbifh has to that of
palace, are deditute of every colour of plaufibility. Ani¬
mal trees, {hips failing in the Iky, armies of monftrous
things travelling between the fun and moon on a pave¬
ment of cobwebs, rival nations of men inhabiting woods
and mountains in a whale’s belly,—are liker the dreams
I2 ol a bedlamite than the inventions of a rational being.
A ftricter If we were to profecute this fubject any farther, it
probability wrould be proper to remark, that in fome kinds of poe-
ibrne kinds ^nventi°n a ftricler probability is required than in
of poetry others :—that, for inftance, Comedy, whether dramatic
than in or narrative (b), muft feldom deviate from the ordinary
others. courfe of human affairs, becaufe it exhibits the manners
of real and even of familiar life :—that the tragic poet,
becaufe he imitates characters more exalted, and gene¬
rally refers to events little known, or long fince paft,
may be allowed a wider range j but muft never attempt
the marvellous fiflions of the epic mufe, becaufe he ad-
dreffes his work, not only to the paflions and imagina¬
tion of mankind, but alfo to their eyes and ears, which
are not eafily impofed on, and refufe to be gratified with
any reprefentation that does not come very near the
truth :—that the epic poem may claim ftill ampler pri¬
vileges, becaufe its fi&ions are not fubjeft to the feru-
TRY. partI.
tiny of any outward lenle, and becaufe it conveys in- Of
formation in regard both to the higheft human charac- Invention,
ters, and the molt intportant and wonderful events, and '“—v—*■*’
alio to the affairs oi unfeen worlds and fuperior beings.
Nor would it be improper to obferve, that the feveral
fpecies of comic, of tragic, of epic compofition, are not
confined to the lame degree of probability ; for that
farce may be allowed to be lefs probable than the regu¬
lar comedy ; the mafque than the regular tragedy ; and
the mixed epic, fuch as the Fairy Queen, and Orlando
Furiofo, than the pure epopee of Homer, Virgil, and
Milton. But this part of the fubjeft feems not to re¬
quire further illuftration. Enough has been faid to
Ihow, that nothing unnatural can pleafe; and that there¬
fore poetry, wnofe end is to pleafe, muft be according to
nature.
And if fo, it muft be either according to real na¬
ture, or according to nature fomewhat different from the
reality.
Sect. III. Of the System of Nature exhibited by Poetryf
To exhibit real nature is the bufinefs cf the hiftorian j
who, if he were ftri&ly to confine himfelf to his own
iphere, v-ould never record even the minuteft circum-
itance of any fpeech, event, or defeription, w hich was
not warranted by fufficient authority. It has been the .
language of critics in every age, that the hiftorian ought JmbelSiT
to relate nothing as true which is falfe or dubious, and their works
to conceal nothing material which he knows to be true, by fiftion.
But it is to be doubted whether any writer of profane and riiake
hiftory lias ever been fo fcrupulous. Thucydides him-them
felf, who began his hiftory when that war began which
he records, and wrho fet dowm every event foon after it
happened, according to the meft authentic information,
feems, however, to have indulged his fancy not a little
in his harangues and deferiptions, particularly that of
the plague of Athens: and the fame thing has been
pra&ifed, with greater latitude, by Livy and Tacitus,
and more or lefs by all the belt hiftorians both ancient
and modern. Nor are they to be blamed for it. By
thefe improved or invented fpeeches, and by the height-
enings thus given to their deferiptions, their w'ork be¬
comes more interefting, and more ufeful; nobody is de¬
ceived, and hiftorical truth is not materially affefted. A
medium is, however, to be obferved in this, as in other
things. When the hiftorian lengthens a defeription in¬
to a delail of fidlitious events, as Voltaire has done in
his account of the battle of Fontenoy, he lofes his cre¬
dit with us, by raifing a fufpicion that he is more in¬
tent upon a pretty ftory than upon the truth. And
we are difgufted with his infincerity, when, in defiance
even of verifimilitude, he puts long elaborate orations in
the mouth of tliofe, of whom w'e know, either from the
circumftances that they could not, or from more authen¬
tic records that they did not, make any fuch orations j
as Dionyfius of Halicarnaffus has done in the cafeofVol
hunnia haranguing her fon Coriolanus, and Flavius Jofe-
phus in that of Judah addrefiing his brother as viceroy
Egypt- From what thefe hiftorians relate, one w-ould
conjecdure
are examples of what may be called the Epic or Nar¬
id) Fielding’s Tom Jones, Amelia, and Jofeph Andrews,
rative Comedy, or more properly perhaps the Comic Epopee.
4
Beattie's
Efays,
chap. ii.
Part IV P. O E
Gf Nature conjecture tliat tlie Roman matron had ftudiedat Athens
/n Poetryunc}er fome long-winded rhetorician, and that the Jewifh
"r patriarch mud have been one of the mod flowery orators
of antiquity. But the fiftitious part of hidory, or of
dory-telling, ought never to take up much room j and
mud be highly blameable when it leads into any mi-
14 dake either of fadls or of char afters,
in fome de- Now, why do hidorians take the liberty to embellilh
£poe' tlielr works in this manner ? One reafon, no doubt, is,
that they may difplay their talents da oratory and na¬
tation : but the chief reafon, as hinted already, is, to
render their compofition more agreeable. It would feem,.
then, that fomething more pleaflng than real nature,
or fomething which ihall add to the pleaflng qualities
of real nature, may be devifed by human fancy. And
this may certainly be done. And this it is the poet’s
bufinefs to do. And when this is in any degree done
by the hidorian, his narrative becomes in that degree
poetical.
The podibility of thus improving upon nature mud
be obvious to every one. When we look at a land-
fcape, we can fancy a thoufand additional embelli (la¬
ments. Mountains loftier and more pidurefque ; rivers
more copious, more limpid, and more beautifully bind¬
ing j fmoother and wider lawns j valleys more richly
diverfified •, caverns and rocks more gloomy and more
flupendous; ruins more majedic ; buildings more mag¬
nificent; oceans more varied with i{lands,.more fplendid
with hipping, or more agitated by dorm, than any we
have ever feen—it is eafy for human imagination to con¬
ceive. Many things in art and nature exceed expecta¬
tion ; but nothing fenflble tranfcends or equals the ca¬
pacity of thought:— a driking evidence of the dignity
of the human foul! The fined woman in the world ap¬
pears to every eye fufceptible of improvement, except
perhaps to that of her lover. No wander, then, if in
poetry events can be exhibited more compact, and of
more pleafing variety, than thofe delineated by the hi-
Bcmin na ^or*an> a!1d fcenes of inanimate nature more dreadful or
ture itfiif more lovely, and human characters more fublime and
more exquifite, both in good and evil. Yet dill let
nature fupply the gvouud;work and materials, as well as
the dandard, of poetical fiction. The mod expert
painters ufe a layman, or other vifible figure, to direct
their hand and regulate their fancy. Homer himfelf
founds his two poems on authentic tradition ; and tragic
as well epic poets have followed the example. The
writers of romance, too, are ambitious to interweave true
adventures with their fables ; and when it can be conve¬
niently done, to take, the outlines of their plan from
real life. Thus the tale of Robinfon Crtifoe is founded,
on an incident that actually befel one Alexander Sel¬
kirk, a feafaring man, who lived feveral years-alone in
the ifland of Juan Fernandes : Smollet is thought to
have given us feveral of his own adventures in the hi¬
dory of Roderic Random ; and the chief charafters in
Tom Jones, Jofeph Andrews, and Pamela, are faid to
have been copied from real originals. Dramatic co¬
medy, indeed, is for the mod part purely fictitious : for
if it were to exhibit real events as well as prefent man-
* Compare ners, it would become too perfonal to be endured by a
Hor. lib. i. well-brecT audience, and degenerate into downright
fat. 4. verf: ahufe; which anpears to have been the cafe with the
i;Xrhold come(fy of the Greeks *. But in general, hints ta-
verf. zSi’—ken from real exidetice will be found to give no little
*5
Poets e n-
feel dill na-
T n Y. 759
grace and dability to fit'iofl, even in the mod fanciful Of Nature
poems. Thefe hints, however, may be improved by the 111 Poctr-v-i
poet’s imagination, and fet pff with every probable orna-
ment that can be devifed, confidently with the defign
and genius of the work ; or in other words, with the
fympathies that the poet means to awaken in the mind
of his reader. For mere poetical ornament, when it
fails to intered the affeclions, is not only ufelefs, but im¬
proper ; all true poetry being addreffed to the heart, and
intended to give plealure by railing or foothing the paf-
lions ;—the only effectual way of plealing a rational and
moral creature. And therefore we would take Ho¬
race’s maxim to be univerfal in poetry “ Non fatis ejl,
pulchra ejfe poemata ; dulcia Junto“ It is not enough
that poems be beautiful; let them alfo be affeciing—
For that this is the meaning of the word dulcia in this 1 -®3r- Ar°
place, is admitted by the bed interpreters, and is indeed *
evident from the context f. ^16
That the fentiments and feelings of percipient beings'ar.d de-
when expreffed in poetry, Ihould call forth our affec.ftnbe
tions, is natural enough ; but can descriptions of inani- f^.^”^9
mate things alfo be made afte&ing ? certainly they can : ^ as t0
and the more they affeft, the more they pleafe us, and n-ake them
the more poetical we allow them to be. Virgil’s Geor- afFedting.
gic is a noble fpecimen (and indeed the nobleit in the
world) of this fort of poetry. His admiration of exter¬
nal nature gains upon a reader of tade* till it rife to per¬
fect enthufiafm. The following obfevvations will per¬
haps explain this matter.
Every thing in nature is complex in itfelf, and bears:
innumerable relations to other things ; and may there¬
fore be viewed in an endlefs variety of lights, and con-
fequently deferibed ill an endlefs variety ol ways. Some-
deferiptions are good, and others bad* An hidorical
defeription, that enumerates all the qualities of any ob-
je£t, is certainly good, hecaufe it is true ; but may be
as unaffe&ing as a logical definition. In poetry, no un-
affefting defeription is good- however conformable to
truth : for here we expecd not a complete enumeration
of qualities (the chief end of the art being to pleafe).
but only fuch an enumeration as may give a lively and
intereding idea. It is not memory, or the knowledge?
of rules!, that can qualify a poet for this fort of deferip¬
tion ; but a peculiar livelmefs of fancy and lenfibility
of heart, the nature whereof we may explain by its-
effe&s, but we cannot lay down rules for the attain¬
ment of it.
When our mind is occupied by any emotion,, we na¬
turally ufe words and meditate on things that are fuit-
able to it and tend to encourage! it. If a- man were to
write a letter when he is very angry, there would pro¬
bably be fomething of vehertence or bitternefs in thrf
ftyle, even though the perfon to whom be wrote were
not the objeft of his anger. The fame thing bolds true
of every other drong padton of emotion -while it pre¬
dominates in the mind, it gives a peculiarity to our.
thoughts, as well as to our voice,, gedure, and counts- ry
nance: And hence we expe£, that every per for. age in-Tvery per--
troduced in poetry diould fee things through the
dium of his ruling paflion, and that his thoughts andp^rym
language fhould be tinftured accordingly. A melan-ihould fee
choly man walking in a grove, attends to thofe thirtgsthings
that fuit and encourage his melancholy ; the fighing of
the wind in the trees, the murmuring of waters, the^j*^™®
darknefs and folitude.of the (hades: A cheerful man in pilfliw3v ““
the-
760 POE
Of Nature the fame place, finds many fubje£ls of cheerful medita-
,111 Foetl>, tions, in the finging of birds, the briflc motions of the
v~' babbling ilream, and the liveL’nefs and variety of the ver¬
dure. Perfons of different charafters, contemplating
the fame thing, a Roman triumph, for inftance, feel dif¬
ferent emotions, and turn their view to different objects.
One is filled with wonder at fuch a difplay of wealth and
power another exults in the idea of conqueft, and pants
for military renown ; a third, ftunned with clamour, and
haraffed with confufion, wifhes for filence, fecurity, and
Beattie's folitude ; one melts with pity to the vanquifhed, and
EJfays, makes many a fad refleflion upon ihe infignificance of
ut fupra. worldly grandeur, and the uncertainty of human things j
while the buffoon, and perhaps the philofopher, con-
fiders the whole as a vain piece of pageantry, which, by
its folemn procedure, and by the admiration of fo many
people, is only rendered the more ridiculous:—and each
of thefe perfons would defcribe it in a way fuitable to
his own feelings, and tending to raife the fame in others.
We fee in Milton’s Allegro and Penforofo, how a dif¬
ferent caft of mind produces a variety in the manner of
conceiving and contemplating the fame rural fcenery.
In the former of thefe excellent poems, the author per-
fonates a cheerful man, and takes notice of thofe things
in external nature that are fuitable to cheerful thoughts,
and tend to encourage them : in the latter, every objedt
defcribed is ferious and folemn, and productive of calm
refleftion and tender melancholy 5 and we fhould not
be eafily perfuaded, that Milton wrote the firft under
the influence of forrow, or the fecond under that of
gladnefs. We often fee an author’s character in his
works; and if every author were in earneft when he
writes, we fhould oftener fee it. Thomfon was a man
of piety and benevolence, and a warm admirer of the
beauties of nature ; and every defcription in his delight¬
ful poem on the Seafons tends to raife the fame laudable
affedtions in his reader. The parts of nature that at¬
tract his notice are thofe which an impious or hard¬
hearted man would neither attend to, nor be affeCted
with, at leaft in the fame manner. In Swift we fee a
turn of mind very different from that of the amiable
Thomfon; little relifh for the fublime or beautiful, and
a perpetual fucceflion of violent emotions. All his pic¬
tures of human life feem to fhow, that deformity and
meannefs were the favourite objeCts of his attention, and
that his foul was a conftant prey to indignation (c),
difguft, and other gloomy paffions, arifing from fuch a
view of things. And it is the tendency of almoft all
his writings (though it was not always the author’s de-
fign), to communicate the fame paflions to his reader :
infomuch, that notwithftanding his erudition and know¬
ledge of the world, his abilities as a popular orator and
man of bufinefs, the energy of his flyle, the elegance of
fome of his verfes, and his extraordinary talents in wit
and humour, there is reafon to doubt, whether by ftu-
dying his works any perfon was very much improved in
piety or benevolence.
And thus we fee, how the compofitions of an inge¬
nious author may operate upon the heart, whatever be
T R Y. Part T.
the fubjeCf. The affeCtions that prevail in the author Of Nature
himfelf, direCt his attention to objeCts congenial, and give in Poetfy-
a peculiar bias to his inventive powers, and a peculiar *
colour to his language. Hence his work, as well as face, jt ;s thus
if nature is permitted to exert herfelf freely in it, will that poetry
exhibit a picture of his mind, and awaken correfpondent affedb the
fympathies in the reader. When thefe are favourable to
virtue, which they always ought to be, the work will^je^lts
have that fweet pathos to which Horace alludes in the
paffage above mentioned j and which we fo highly ad¬
mire, and fo warmly approve, even in thofe parts of the
Georgic that defcribe inanimate nature.
Horace’s account of the matter in queltion differs not
from what is here given. “ It is not enough (lays he *) *
that poems be beautiful 5 let them be affeCting, and v.^.—m
agitate the mind with whatever paflions the poet wilhes
to impart. The human countenance, as it fmiles on
thofe who fmile, accompanies alfo with fympathetic tears
thofe who mourn. If you would have me weep, you
muft firft weep yourfelf} then, and not before, lhall I be
touched with your misfortunes.—For nature firft makes
the emotions of our mind correfpond with our circum-
ftances, infufing real joy, forrow, or refentment, accord¬
ing to the occafion ; and afterwards gives the true pa¬
thetic utterance to the voice and language.” This
doctrine, which concerns the orator and the player no
lefs than the poet, is ftrictly philofophical, and equally
applicable to dramatic, to defcriptive, and indeed to
every fpecies of interefting poetry. The poet’s fenlibi-
lity muft firft of all engage him warmly in his fubjeft,
and in every part of it; otherwife he will labour in vain
to intereft the reader. If he would paint external nature,
as Virgil and Thomfon have done, fo as to make her
amiable to others, he muft firft be enamoured of her him¬
felf ; if he wxmld have his heroes and heroines fpeak the
language of love or forrow, devotion or courage, ambi¬
tion or anger, benevolence or pity, his heart muft be
fufceptible of thofe emotions, and in fome degree feel
them, as long at leaft as he employs himfelf in framing
words for them; being affured, that
He beft ftiall paint them who can feel them moft.
Pope’s FJoifa, v. 366.
The true poet, therefore, muft not only ftudy nature, *9
and know the reality of things, but mult alfo poffefs ^
fancy, to invent additional decorations j judgment, to p0(fefs fan_
diredl him in the choice of fuch as accord with verifi- cy to in-
militude j and fenfibility, to enter with ardent emotions yeiy deco-
into every part of his fubjedt, fo as to transfufe into eve-ratlons t0
ry part of his work a pathos and energy fufficient to
raife correfponding emotions in the reader.
“ The hiftorian and the poet (fays Ariftotle *) dif- * poetic
fer in this, that the former exhibits things as they are,fccyt
the latter as they might be 5”—i. e. in that ftate of per¬
fection which isconfiftent with probability, and in which,
for the fake of our own gratification, w7e wilh to find
them. If the poet, after all the liberties he is allowed
to take with the truth, can produce nothing more ex-
quifite than is commonly to be met with in hiftory, his
reader
(c) For part of this remark we have his own authority, often in his letters, and very explicitly in the Latin
epitaph which he compofed for himfelf“ ubi feeva indignatio ulterius cor lacerare nequit.” See his Iq/i wi// and
tejlament.
%
Parti. POE
Of Nature reader will be difappointed and diflatisfied. Poetical re¬
in Poetry, prefentations muft therefore be framed after a pattern of
 the higheft probable perfedlion that the genius of the
work will admit;—external nature muft in them be
more pi&ureique than in reality j aftion more animated;
fentiments more expreftive of the feelings and chara&er,
and more fuitable to the circumftances of the fpeaker ;
perfonages better accompliftied in thofe qualities that
raife admiration, pity, terror, and other ardent emo¬
tions 5 and events more compact, more clearly connefl-
ed with caufes and confequences, and unfolded in an
order more flattering to the fancy, and more interefting
to the paflions. But where, it may be faid, is this pat¬
tern of perfeftion to be found ? Not in real nature 5
otherwife hiftory, which delineates real nature, would
alfo delineate this pattern of perfe£Hon. It is to be
found only in the mind of the poet j and it is imagina¬
tion, regulated by knowledge, that enables him to form it.
In the beginning of life, and while experience is con¬
fined to a fmall circle, we admire every thing, and are
pleafed with very moderate excellence* A peafant thinks1
the hall of his landlord the fineft apartment in the uni-
verfe, liftens with rapture to the ftrolling ballad-finger,
and wonders at the rude wooden cuts that adorn his
ruder compofitions. A child looks upon his native vil¬
lage as a town; upon the brook that runs by as a ri¬
ver ; and upon the meadows and hills in the neighbour¬
hood as the moft fpacious and beautiful that can be.
But when, after long abfence, he returns in his de¬
clining years, to vifit, once before he die, the dear fpot
that gave him birth, and thofe fcenes whereof he re¬
members rather the original charms than the exa£t pro¬
portions ; how is he difappointed to find every thing fo
debafed and fo diminifhed ! The hills feem to have funk
into the ground, the brook to be dried up, aad the vil¬
lage to be forfaken of its people j the parifh-church,
ftripped of all its fancied magnificence, is become low*
gloomy, and narrow; and the fields are now only the
miniature of what they were. Had he neker left this
fpot, his notions might have remained the fame as at
firft } and had he travelled but a little way from it, they
would not perhaps have received any material enlarge-
Obfervation ment. It feems then to be from obfervation of many
of many things of the fame or fimilar kinds, that we acquire the
things of talent of forming ideas more perfect than the real ob-
ktn/j^reat je<^s t^lat ^ immediatety around us : and thefe ideas we
help tffpoe- may improve gradually more and more, according to the
tical fancy, vivacity of our mind, and extent of our experience, till at
hecaufe laft We come to raife them to a degree of perfection fu-
perior to any thing to be found in real life. There can¬
not fure be any myftery in this doCtrine ; for we think
and fpeak to the fame purpofe every day. Thus nothing
is more common than to fay* that finch an artift excels
all we have ever known in his profeffion, and yet that
we can flill conceive a fuperior performance. A mo-
ralift, by bringing together into one view the feparate
virtues of many perfons, is enabled to lay down a fyf-
tem of duty more perfeCt than any he has ever feen ex¬
emplified in human conduCt. Whatever be the emo¬
tion the poet intends to raife in his reader, whether ad¬
miration or terror, joy or forrow; and whatever be the
objeCl he would exhibit, whether Venus or Tifiphone,
Achilles or Therfites, a palace or a pile of ruins, a
dance or a battle •, he generally copies an idea of his
own imagination *, confidering ©ach quality as it is
VOL. XVI. Part II.
T R Y. 76‘
found to exift in feveral individuals of a fpecies, and Natul?
thence forming an afiemblage more or lefs perfect in its m 1 -N
kind, according to the purpoie to which he means to ap¬
ply it. 21
Hence it would appear, that the ideas of poetry are poetical
rather general than Angular j rather collected from ^ufTbe ge*.
examination of a fpecies or clafs of things, than copiednera^
from an individual. And this, according to Ariftotle,
is in faCt the cafe, at ieaft for the moft part ^ whence
that critic determines, that poetry is fomething more ^ pgctii.r
exquifite and more philofophical than hiftory*. I he hi-. ^
ftorian may defcribe Bucephalus, but the poet delineates
a war-horfe j the former muft have feen the animal he
fpeaks of, or received authentic information concern¬
ing it, if he mean to defcribe it hiftorically *, for the
latter, it is enough that he has feen feveral animals
of that fort. The former tells us, what Achilles ac¬
tually did and faid 5 the latter, what fuch a fpecies of
human charafter as that which bears the name of Achil¬
les would probably do or fay in certain given circum¬
ftances.
It is indeed true, that the poet may, and often does,
copy after individual objefts. Homer, no doubt, took
his characters from the life } or at leaft, in forming
them, was careful to follow tradition as far as the na¬
ture of his plan would allow. But he probably took
the freedom to add or heighten feme qualities, and
take away others 5 to make Achilles, for example,
ftronger, perhaps, and more impetuous, and more emi¬
nent for filial affeCtion, and HeCtor more patriotic and
more amiable than he really Was. If he had not done
this, or fomething like it, his work would have been
rather a hiftory than a poem •, would have exhibited
men and things as they were, and not as they might
have been j and Achilles and HeSlor would have been the
names of individual and real heroes $ whereas, according
to Ariftotle, they are rather to be confidered as two
diftinft modifications or fpecies of the heroic character.
Shakefpeare’s account of the cliffs of Dover comes fo
near the truth, that we cannot doubt of its having been
written by one who had feen them : but he who takes
it for an exaft hiftorical defeription, will be furprifed
wrhen he comes to the place, and finds thofe cliffs not
half fo lofty as the poet had made him believe. An
hiftorian would be to blame for fuch amplification}
becaufe, being to defcribe an individual precipice, he
ought to tell us juft what it is j which if he did, the
defeription would fuit that place, and perhaps no other
in the whole world. But the poet means only to give
an idea of what fuch a precipice may be ; and therefore
his defeription may perhaps be equally applicable to ma¬
ny fuch chalky precipices on the fea fhore.
This method of copying after general ideas formed
by the artift from obfervation of many individuals, di-
ftinguiihes the Italian and all the fublime painters,
from the Dutch and their imitators. Thefe give us
bare nature, with the imperfettions and peculiarities
of individual things or perfons \ but thofe give nature
improved as far as probability and the defign of the
piece will admit. Teniers and Hogarth draw faces,
and figures, and dreffes, from real life, and prefent man¬
ners ", and therefore their pieces muft in fome degree
lofe the effeft, and become aukward, when the prefent
faftiions become obfolete. Raphael and Reynolds
take their models from general nature j avoiding, as
5 D 'for
762
P 6 E
Of Nature far as pomble, (at lead in ail their great performances),
m Poetry. |]-10fe peculiarities that derive their beauty from mere
in order to
pleafe all
ages and
countries.
^ 43 •
The period
in the pro.
3 refs of hu-
ifsould a
teed.
peculiar
falhion •, and therefore their works mull; give pleafure,
and appear elegant, as long as men are capable of.fonm-
ing general ideas, and of judging from them. The
biff-mentioned incomparable arliit is particularly ob-
fervant of children, whofe looks and attitudes, biting
lefs under the controul of art and local manners, are
more characteriftical of the fpecies than thofe of men
and women. This field of obfervation has fupplied
him with many fine figures, particularly that molt ex-
q alike one of Comedy, ftruggling for and winning (for
who could refill her I) the affections of Garrick :—a
figure which could never have occurred to the imagi¬
nation of a painter who had confined his views to
grown perfons looking and moving in all the forma¬
lity cf.polite life5—a figure which in all ages and coun¬
tries would be pronounced natural and engaging:—
whereas thofe human forms that we fee every day bow¬
ing and courtefying, and flrutting, and turning out
their toes fecundum ortem, and clreffed in ruffles, and
wigs, and flounces, and hoop-petticoats, and full-trim¬
med fuits, Would appear elegant no further than the pi e-
fent faflfions are propagated, and no longer than they
remain unaltered.
There is, in the progrefs of human fociety, as well
as of human life, a period to which it is of great im-
porlanec for the higher order of poets to attend, and
to which ' ^rom which they will do well to take their chara&er.s,
epic and and manners, and the era of their events; namely,
tragic poets that wherein men are raifed above favage life, and con-
fiderabiy improved by arts, government, and conver-
fation } but not advanced fo high in the afeent towards
politenefs, as to have acquired a habit of difguifing
their thoughts and paflions, and of reducing their be¬
haviour to the uniformity of the mode. Such was the
period which Homer had the good fortune (as a poet) to
live in, and to celebrate. This is the period at which the
manners of men are mofl picturefque, and their adven¬
tures moft romantic. This is the period when the ap¬
petites unperverted by luxury, the powers unnervat-
ed by effeminacy, and the thoughts difengaged from
artificial reftraint, wall, in perfons of fimilar dif-
pofitions and circumflances, operate in nearly the fame
way 5 and when, confequently, the charafters of par¬
ticular men will approach to the nature of poetical ter
general ideas, and, if well imitated, give pleafure to the
whole, or at leaft to a great majority cf mankind.
But a charafler tinctured with the fafhions of polite life
wTould not be fo generally interefting. Like a human
figure adjufted by a modern dancing-mafter, and clref¬
fed by a modern tailor, it may have a good effedt in'
fatire, comedy, or farce: but if introduced into the
higher poetry, it would be admired by thofe only who
had learned to admire nothing but prefent faflfions,
and by them no longer than the prefent faflfions laft-
ed ■, and to all the reft of the world would appear auk-
ward, unaffedting, and perhaps ridiculous. But A-
chilles and Sarpedon, Diomede and Hedtor, Neftor
and Ulyffes, as drawn by Homer, muft in all ages, in¬
dependently on fafniou, command the attention and ad¬
miration of mankind. Thefe have the qualities that are
univerfally known to belong to human nature ; whereas
the modern fine gentleman is diftinguifhed by qualities
that belong only to a particular age, fociety, and cor-
T R Y. Fart I.
tier of the world. We fpeak not of moral or in telle c- Of Pot tic at
tual virtues, which are objedls of admiration to every Characters,
age ; but of thole outward accomplifhments, and that v' *
particular temperature cf the paflions, which form the
moft perceptible part of a human charadler. —As,
therefore, the politician, in difcufflng the rights of
mankind, muft ofien allude to an imaginary ftate of na¬
ture 5 fo the poet who intends to raife admiration, pity,
terror, and other important emotions, in the generality
of mankind, especially in thole readers whofe minds are
moft improved, muft take his pidtures of life and man¬
ners, rather from the heroic period wre now Ipea'k of,
than from the ages of refinement: and muft therefore
(to repeat the maxim of Ariftotle) “ exhibit things, not
as they arc, but as they might be.”
Sect. IV. Of Poetical CJiaracfers.
Horace feems to think, that a competent know- Rcquintes
ledge of moral philofophy will fit an author for aflign-"to the deli,
ing the fuitable qualities and duties to each poeticalneation
peifonage : (Art. Poet. v. 309.-—316.J The maxim
may be true, as far as mere morality is the aim of the
poet} but cannot be underftood to refer to the- deline¬
ation of poetical charadlers in general : for a thorough
acquaintance with all the moral philofophy in the wOrld
v/ould not have enabled Blackmore to paint foch a per-
fonage as Homer’s Achilles, Shakefpeare’s Othello, or
the Satan of Paradife Loft. To a competency of mo¬
ral foience, there muft be added an extenlive knowledge
of mankind, a warm and elevated imagination, and the
greateft fenfibility of heart, before a genius can be for¬
med equal to fo difficult a talk. Horace is indeed lo
fenfible of the danger of introducing a new character in
poetry, that he even difeourages the attempt, and ad-
vifes the poet rather to take his perfons from the an¬
cient authors, or from tradition: Paid. v. 119.—130.
To conceive the idea of a good man, and to invent,
and fupport a great poetical character, are two very
different things, however they may feem to have been
confounded by fome late critics. The firft is eafy to
any perfon fufficiently inifrufted in the duties cf life :
the haft is perhaps of all the efforts of human genius
the moft difficult 5 fo very difficult, that, though at¬
tempted by many, Homer, Shakefpeare, and Milton,
are almoft the only authors who have iucceeded in it.
But characters of perfect virtue are not the moft pro¬
per for poetry. It feems to be agreed, that the Dei¬
ty ftiould not be introduced in the machinery of a poe¬
tical fable. To aferibe to him words and adfions of
our own invention, feems very unbecoming; nor can
a poetical defeription, that is known to be, and muft
of neceffity be, infinitely inadequate, ever fatisfy the
human mind. Poetrv, according to the belt critics,Which,
is an imitation of human afition ; and therefore poeti-taoufftie‘e“
cal characters, though elevated, ftiould ftill partake of
the paffions and frailties of humanity. If it were not ta]ie 0f the
for the vices of fome principal perfonages, the Iliad fiailties of
would not be either fo ifiterefting or fo moral: theHnnanity;
moft moving and moft eventful parts of the Aineid are
thofe that tlefcribe the e fie fits of unlawful paffion :—
the molt inftrufitive tragedy in the world, we mean
Macbeth, is founded in crimes of dreadful enormity :
—and if Milton had not taken into his plan the fall of
our firft parents?. as well as their ftate of innocence,
Part I.
Of Poetical
Charadters.
26
whilft t e
perforin pes
in whofe
fate the
poet means
th>t we
fliould be
inte; tiled
cu hr to
have good
and great
qualities.
P O E
lus divine fisuft have v,’anted much of its pathos,
and could not have been (what it now is) fuch a trea-
fuve of important knowledge, as no other uninfpired
writer ever comprehended in fo fmall a compafs. 
Virtue, like truth, is uniform and unchangeable. We
may anticipate the part a good man will acb in any gi¬
ven circumftances: and therefore the events that de¬
pend on fuch a man muft be lefs furprifing than thofe
which proceed from paffion ; the viciflitudes whereof
it is frequently impoffible to forefee. From the vio¬
lent temper of Achilles, in the Iliad, fpring many great
incidents •, which could not have taken place, if he had
been calm and prudent like Ulyffes, or pious and pa¬
triotic like Eneas: his reje&ion of Agamemnon’s of¬
fers, in the ninth book, avifes from the violence of his
refentment;—his yielding to the requeft of Patroclus,
in the 16th, from the violence of his friendlhip (it we
may fo fpeak) counteradfing his refentment ; and his
reftoring to Priam the dead body of Hedtor, in the
24th, from the violence of his affedhon to his own aged
father, and his regard to the command of Jupiter, coun-
teradfing, in feme meafure, both hisforrow for his friend,
and his thirft for vengeance. Befides, except where
there is feme degree of vice, it pains us too exqmfitely
to fee misfortune ; and therefore poetry would ceafe to
have a pleaiurable influence over our tender paflions, if
it were to exhibit virtuous charadfers only. And as in
life, evil is neceffary to our moral probation, and the
poffibility of error to our intelledfual improvement; lo
bad or mixed charadters are uftful in poetry, to give to
the good fuch oppofition, as puts them upon difplaying
and exercifing their virtue.
All thofe perfpnnges, however, in whofe fortune
the poet means that we fhould be interefted, muft have
agreeable and admirable qualities to recommend them
to our regard. And perhaps the greateft difficulty in
the art lies in fuitably blending thofe faults which the
poet finds it expedient to give to any particular hero,
with fuch moral, intelledfual, or corporeal accomplifii-
ments, as may engage our efteem, pity, or admira¬
tion, without weakening our hatred of vice, or love
of virtue. In moft of our novels, and in many of our
plays, it happens unluckily, that the hero of the piece
is fo captivating, as to incline us to be indulgent to
every part of his charadfer, the bad as well as the
good. But a great mailer knows 'how to give the pro¬
per diredfion to human fenfibility; and, without any
perverfion of our faculties, or any confufion of right
and wrong, to make the fame , perfon the objedl of
very different emotions, of pity and hatred, of admi¬
ration and horror. Who does not efteem and admire
Macbeth for his courage and generofity ? who does
not pity him when befet with all the terrors of a preg¬
nant Imagination, fuperftitious temper, and awakened
cenfcience ? who does not abhor him as a monfter of
T It Y.
cruelty, treachery, and ingratitude? His good quali-Ot Poetical
ties, by drawing us near to him, make us, as it were, fiiar^c' erS;,
cye-witneffes of his crime, and give us a fellow-feel¬
ing of his remorfe; and therefore, his example cannot
fail to have a powerful effedt in cheriftting our love of
virtue, and fortifying our minds againft criminal im-
preffxons } whereas, had he wanted thofe good quali¬
ties, we fhould have kept aloof from his concerns, or
viewed them with a fuperficial attention ; in which cafe ,
his example would have had little more weight than
that of the robber, of whom we know nothing, but
that he was tried,. condemned, and executed.—Satan,
in Paradife Loft, is a charadler drawn and fupported
with the moft confummate judgement. The old furie-s
and demons, Hecate, Tifiphone, Alcdlo, Megara, are
objedfs of unmixed and unmitigated abhorrence ; Ti-
tyus, Enceladus, and their brethren, are remarkable
for nothing but impiety, deformity, and vaftnefs of fize j
Pluto is, at bell, an infipid perfonage 5 Mars, a hair¬
brained ruffian ; Taffo’s infernal tyrant, an ugly and
overgrown monfter :—but in the Miltonic Satan, we
are forced to admire the majefty of the ruined arch¬
angel, at the lame time that we deleft the unconquer¬
able depravity of the fiend. “ But, of all poetical cha- Beattie's
rafters, (fays the elegant critic from whom we are ex-
trafting), the Achilles of Homer (d) feems to me the
moft exquifite of invention, and the moft highly finilh-
ed. The utility of this charafter in a moral view is
obvious 5 for it may be confidered as the fource of all
the morality of tire Iliad. Had not the generous and
violent temper of Achilles determined him to patronize
the augur Calchas in defiance of Agamemnon, and af¬
terwards, on being affronted by that vindiftive com¬
mander, to abandon for a time the common caufe of
Greece j—the fatal effefts of diffenfion among confede¬
rates, and of capricious and tyrannical behaviour in a fo-
vereign, would not have been the leading moral of Ho¬
mer’s poetry; nor could Heftor, Sarpedon, Eneas, Ulyf¬
fes, and the other amiable heroes, have been brought
forward to fignalize their virtues, and to recommend
themfelves to the efteem and imitation of mankind. 27
“ They who form their judgement of Achilles from The excel-
the imperfeft (ketch given of him by Horace in the Art the
of Poetry, (v. 121, 122.) ; and confider him only as a[!°?dr‘^r
hateful compofition of anger, revenge, fiercenefs, obfti-0f Ackilie^
nacy and pride, can never enter into the views of Ho- and
mer, nor be fuitably affefted with his narration. All
thefe vices are no doubt, in fome degree, combined in
Achilles; but they are tempered with qualities of a dif¬
ferent fort, which render him a moft interefting charac¬
ter, and of courfe make the Iliad a moft interefting
poem. Every reader abhors the faults of this hero :
and yet, to an attentive reader of Homer, this hero muft,
be the objeft of efteem, admiration, and pity ; for he
has many good as well as bad affeftiens, and is equally
5 D 2 violent
(d) “ I fav the Achilles of HOMER. Later authors have degraded the charafter of this hero, by fuppofmg
every part of his body invulnerable except the heel. I know not how often I have heard this urged as one of
Homer’s abfurdities; and indeed the whole Iliad is one continued ubfurdity, on this fuppofitron. But Ho¬
mer all along makes his hero equally liable to wounds and death with other men. Nay, to prevent all mi-
flakes in regard to this matter, (if thofe who cavil at the poet would but read his work), he aftually xvounds
him in the right arm by the lance of Afteropceus, ia the battle near the river Scamahder.” See Had, xxfr
verfe i6x—168.
POE
<"h iraclei**' V1'°^e!lt *n :—Nor is he pofTeiTed of a Angle vice or
. e';‘. virtue, which the wonderful art of the poet has not
made fubfervient to the defign of the poem, and to the
progrefs and cataftrophe of the action; fo that the hero
ol the Iliad, confidered as a poetical perfonage, is juft
what he lliould be, neither greater nor lels, neither
worfe nor better.—He is everywhere diftinguifhed by
an abhorrence of oppreftion, by a liberal and elevated
mind, by a paftion for glory, and by a love of truth,
freedom, and fincerity. He is for the moft part atten¬
tive to the duties of religion *, and, except to thofe who
have injured him, courteous and kind : he is affedlionate
to his tutor Phenix ; and not only pities the misfortunes
of his enemy Priam, but in the moft foothing manner
adminifters to him the beft confolation that Homer’s
poor theology could furniih. Though no admirer of
the caufe in which his evil deftiny compels him to en¬
gage, he is warmly attached to his native land *, and,
ardent as he is in vengeance, he is equally fo in love to
his aged father Peleus, and to his friend Patroclus. He
is not luxurious like Paris, or clownilh like Ajax •, his
accomplifhments are princely, and his amufements wor¬
thy of a hero. Add to this, as an apology for the vehe¬
mence of his anger, that the affront he had received
was (according to the manners of that age) of the moft
atrocious nature } and not only unprovoked, but fuch
as, on the part of Agamemnon, betrayed a brutal in-
fenftbility to merit, as well as a proud, felfilh, ungrate¬
ful, and tyrannical difpolition. And though he is of¬
ten inexcufably furious ; yet it is but juftice to remark,
l^hat he was not naturally cruel (r.) 5 and that his
Avildeft outrages were fuch as in thbfe rude times might
be expefted from a violent man of invincible ftrength
and valour, when exafperated by injury, and frantic
with forrow.—Our hero’s claim to the admiration of
mankind is indifputable. Every part of his charafter
is fublime and aftoniftiing. In his perfon, he is the
ftrongeft, the fwifteft, the moft beautiful of men :—this
laft circumftance, however, occurs not to his own obfer-
vation, being too trivial to attraft the notice of fo great
a mind. The Fates had put it in his power, either to
return home before the end of the war, or to remain at
Troy :—if he chofe the former, he would enjoy tran¬
quillity and happinefs in his own country to a good old
age •, if the latter, he muft perifh in the bloom of his
youth :—his affettion to his father and native country,
and his hatred to Agamemnon, ftrongly urged him to
the firft ; but a ddire to avenge the death of his friend
determines him to accept the laft, with all its confequen-
ces. This at once difplays the greatnefs of his forti¬
tude, the wrarmth of his friendlhip, and the violence of
his fanguinary paffions : and it is this that fo often and
fo powerfully recommends him to the pity, as well as
23 admiration, of the attentive reader.”
of all Ho- It is equally a proof of rich invention and exaft
wer’s cha- judgement in Homer, that he mixes feme good qualities
1,1 er ' in all his bad charafters, and fome degree of imperfec¬
tion in almoft all his good ones.—Agamemnon, not-
withftanding his pride, is an able general, and a valiant
T It Y. Part I.
man, and highly eftefemed as fuch by the greater part bfOfPostieal
the army.—Paris, though effeminate, and vain of hisCliara(^ers'
drefs and perfon, is, however, good-natured, patient of v—'
reproof, not deftitute of courage, and eminently Ikilled
in mufic and other fine arts.—Ajax is a huge giant;
fearlefs rather from infenfibility to danger, and confi¬
dence in his maffy arms, than from any nobler principle j
boaftful and rough ; regardlefs of the gods, though not
downright impious: yet there is in his manner fomething Benttie
of franknefs and blunt fincerity, which entitle him to aut fupra,
lhare in our efteem ; and he is ever ready to aftift his
countrymen, to wjhom he renders good fervice on
many a perilous emergency. The character of He¬
len, in fpite of her faults, and of the many calamities
whereof the is the guilty caufe, Homer has found means
to recommend to our pity, and almoft to our love 5 and
this he does, without feeking to extenuate the crime
of Paris, of wliich the moft refpeftable perfonages in
the poem are made to fpeak w'ith becoming abhorrence.
She is fo full of remorfe, fo ready on every occafion
to condemn her pad; condiuft, fo affeiftionate to her
friends, fo willing to do juftice to every body’s merit,
and wnthal fo finely accomplifhed, that fhe extorts our
admiration, as well as that of the Trojan fenators 
Menelaus, though fufficiently fenfible of the injury he
had received, is yet a man of moderation, clemency, and
good-nature, a valiant foldier, and a moft affeblionate
brother : but there is a dafh of vanity in his compofi-
tion, and he entertains rather too high an opinion of his
own abilities, yet never overlooks nor undervalues the
merit of others.—Priam would claim unreferved efteem,
as well as pity, if it Avere not for his inexcufeable weak-
nefs, in gratifying t1 e humour, and by indulgence abet¬
ting the crimes, of the moft worthlefs of all his chil¬
dren, to the utter ruin of his people, family, and king¬
dom. Madame Dacier fuppofes, that he had loft his
authority, and wras obliged to fall in with the politics of
the times: but of this there appears no evidence 5 on
the contrary, he and his unworthy favourite Paris feem
to have been the only perfons of diftirwftion in Troy
who were averfe to the reftoring of Helen. Priam’s
foible (if it can be called by fo foft a name), however
faulty, is not uncommon, and has often produced cala-
itiity both in private and public life. The Scripture
gives a memorable inftance in the hiftory of the good
old Eli. Sarpedon comes nearer a perfetft charafter
than any other of Homer’s heroes ; but the part he has
to a<ft is fhort. It is a charafter which one could hard¬
ly have expelled in thofe rude times: a fovereign prince,
Avho confiders himfelf as a magiftrate fet up by the
people for the public good, and therefore bound in ho¬
nour and gratitude to be himfelf their example, and
ftudy to excel as much in virtue as in rank and authorF
ty. Heffor is the favourite of every reader, and Avith
good reafon. To the trueft valour he joins the moft ge¬
nerous patriotifm. He abominates the crime of Pads :
but not being able to prevent the Avar, he thinks it his
duty to defend his country, and his father and fove¬
reign, to the laft. He too, as Avell as Achilles, fore fees
his.
. (e) See I/itiJ xxi. 100. and xxiv. 485—673.—In the firft of thefe paffages, Achilles himfelf declares, that be¬
fore Patroclus was flain, he often fpared the lives of his enemies, and took pleafure in doing it. It is ftrange, as
Dr Beattib obferves, that this Ihould be left out in Pope’s Tranflation.
Part I.
€>f Poetical his ovVn death j which heightens our compaflion, and
characters. raifes oui' idea of his magnanimity. In all the relations
' ^ of private life, as a fon, a father, a hulband, a brother,
he is amiable in the higheft degree j and he is diftin-
guifhed among all the heroes for tcndernefs of affe&ion,
gentlenefs of manners, and a pious regard to the duties
of religion. One circumftance of his chara£ter, ftrong-
ly expreffive of a great and delicate mind, we learn
from Helen’s lamentation over his dead body, that he
was almoft the only perfon in Troy who had always
treated her wdth kindnefs, and never uttered one re¬
proachful word to give her pain, nor heard others re¬
proach her without blaming them for it. Some ten¬
dency to oftentation (which, however, may be pardon¬
able in a commander in chief), and temporary fits of
timidity, are the only blemhhes difcoverable in this he¬
ro 5 whofc portrait Homer appears to have drawn with
an affectionate and peculiar attention.
By afcribing fo many amiable qualities to HeCIor and
fome others or the Trojans, the poet interefts us in the
fate of that people, notwithflanding our being conti¬
nually kept in mind that they are the injurious party.
And by thus blending good and evil, virtue and frailty,
in the compofition of his characters, he makes them
the more conformable to the real appearances of human
nature, and more ufeful as examples for our improve¬
ment j and at the fame time, without hurting verifimi-
litude, gives every neceffary embellilhment to particular
parts of his poem, and variety, coherence, and anima¬
tion, to the whole fable. And it may alfo be obferved,
that though feveral of his characters are complex, not
one of them is made up of incompatible parts : all are
natural and probable, and fuch as we think we have
met wdth, or might have met with, in our intercourfe
with mankind.
From the fame extenfive views of good and evil, in
all their forms and combinations, Homer has been ena¬
bled to make each of his characters perfectly diltinCt in
itfelf, and different from all the reft j infomuch, that be¬
fore we come to the end of the Iliad, we are as well ac-
quainted with his heroes, as with the faces and tempers
Virgil fa lb of our moft familiar friends. Virgil, by confining him-
in drawing felf to a few general ideas of fidelity and fortitude, has
xfearaCters. mac|e fubordinate heroes a very good fort of people j
but they are all the fame, and we have no clear know¬
ledge of any one of them. Achates is faithful, and
Gyas is brave, and Cloanthus is brave ; and this is all
we can fay of the matter. We fee thefe heroes at a
diftance, and have fome notion of their ftiape and fize ;
but are not near enough to diftinguilh their features;
and every face feems to exhibit the fame faint and am¬
biguous appearance. But of Homer’s heroes we know
every particular that can be known. We eat, and drink,
and talk, and fight, with them : wre fee them in aCIion
and out of ity in the field and in their tents and houfes :
the very face of the country about Troy we feem to be
as w^ell acquainted with as we had been there. Si¬
milar characters there are among thefe heroes, as there
are fimilar faces in every fociety ; but rve never miftake
one for another. Neftor and Ulyfles are both wife and
both eloquent: but the wdfdom of the former feems to
be the effeCt of experience •, that of the latter of genius :
the eloquence of the one is fweet and copious, but not
always to the purpofe, and apt to degenerate into ftory-
telling j that of the other is clofe, emphatical, and per-
7^5
fuafive, and accompanied with a peculiar modefty and Of Poetical
fimplicity of manner. Homer’s heroes are all valiant; ^iarac^ers'.
yet each difplays a modification of valour peculiar to ' v f
him (elf-, one is valiant from principle, another from con-
ftitution ; one is ralh, another cautious; one is impe¬
tuous and headftrong, another impetuous, but tradable j
one is cruel, another merciful $ one is infolcnt and often-
tatious, another gentle and unafluming j one is vain of
his perfon, another of his ftrength, and a third of his
family—It would be tedious to give a complete enu¬
meration. Almoft every fpecies of the heroic charader
is to be found in Homer.
Of the agents in Paradife Loft, it has been obferved *, *
that “ the weakeft are the higheft and nobleft of human Milton.
beings, the original parents of mankind ; with whofe
adions the elements confented 5 on whofe reditude or
deviation of will depended the ftate of terreftrial nature,
and the condition of all the future inhabitants of the
globe. Of the other agents in the poem, the chief are
fuch as it is irreverence to name on flight occafions : the
reft are lower pow-ers ;
 Of w-hich the leaft could wield
Thefe elements, and arm him with the force
Of all their regions :
Powers, which only the -controul of Omnipotence re- Tlie ‘h®-
ftrains from laying creation wafte, and filling the vaft ^ulty.°f
expanfe of fpace with ruin and confufion. To difplay and'difcri-
the motives and adions of beings thus fuperior, fo far as minating
human reafon can examine, or human imagination re- the cha-
prefent them, is the talk which Milton undertook and rat^ef.s ,a -
performed. The charaders in the Paradife Loft, which Loft 16
admit of examination, are thofe of angels and of men :
of angels good and evil j of man in his innocent and
finful ftate.
“ Among the angels, the virtue of Raphael is mild and
placid, of eafy condefcenfion, and free communication :
that of Michael is regal and lofty, attentive to the dig¬
nity of his ow n nature. Abdiel and Gabriel appear oc-
cafionally, and ad as every incident requires : the foli-
tary fidelity of Abdiel is very amiably painted.
“ Of the evil angels, the charaders are more diver-
fified. To Satan fuch fentiments are given as fuit the
moft exalted and moft depraved being. Milton has-
been cenfured for the impiety which fometimes breaks
from Satan’s raouth ; for there are thoughts, it is juftly
remarked, which no obfervation of charader can jullify j
becaufe no good man would willingly permit them to*
pafs, however tranfiently, through his mind. This cen-
fure has been fhown to be groundlefs by the great critic
from whom we quote. To make Satan fpeak as a rebel,
fays he, without any fuch expreflions as might taint the
reader’s imagination, was indeed one of the great diffi¬
culties in Milton’s undertaking 5 and I cannot but think
that he has extricated himtelf with great happinefs. ^
There is in Satan’s fpeeches little that can give pain to Milton’s
a pious ear. The language of rebellion cannot be the facccfs in
fame with that of obedience : the malignity of Satan
foams in haughtinefs and obftmacy ; but his expreffions facing
are commonly general, and no otherwife offenfive than
as they are w-icked.—The other chiefs of the celeftial'
rebellion are very1 judicioufly difcriminated ; and the fe¬
rocious charader of Moloch appears, both in the battle
aud hi the council^ with exad conliftency.
POETRY.
“ T*
766 POE
Xi-a'-e*1 * * * ' To_AJam and lo Eve ate given, during their inno-
meat, See." cence> luc51 _ fentiments as innocence can generate and
utter. Their love is pure benevolence and mutual vene¬
ration ; their repafts are without luxury, and their dili¬
gence without toil. Their addrefies to their Maker
have'little more than the voice of admiratio:* and grati¬
tude : fruition left them nothing to alk, and innocence
left them nothing to fear. But with guilt enter diitruft
and difeord, mutual accufation and ftubborn felf-de-
fence : they regard each other with alienated minds, and
dread their Creator as the avenger of their tranfgref-
fon 5 at fall, they feek fhelter in his mercy, foften to
repentance, and melt in Application. Both before and
after the fall, the different fentirnents arifing from dif¬
ference of !ex are traced out with inimitable delicacy
and philofophical propriety. Adam lias always that pre¬
eminence in dignity, and Eve in lovelinefs, which we
fhould naturally look for in the father and mother of
mankind.”
From what has been faid, it feems abundantly evident,
--—That the end of poetry is to pleafe; and therefore
that the mod perfect poetry muft be the mod pleafmg ;
’ what is unnatural cannot give pleafure ; and
therefore that poetry mud be according to nature : 
that it mud be eitner accoroing to real nature, or ac-
32 cording to nature fomewhat different from the’reality ;
Poetry ac- "—that, if according to real nature, it v/ould p-ive no
coming to greater pleafure than hidory, which is a tranfeript of
proved to" real "ftui*e i~that greater pleafure is, hoivever, to be
that degree exPe&e<* “rom becaufe we grant it Aperior indul-
whichis gence, in regard to fidion, and the choice of words; 
conti nent and, confequently, that poetry mud be, not according
Vibii t™ t0 real nat.Ure’ but accordhig to nature improved to that
d,lil y- degree which is confident with probability and fuitable
to the poet’s purpofe. And hence it is that we call
poetry, Jti imitation of nature,—For that which is pro¬
perly termed imitation has always in it fomethino- which
is iiol rn Liie original. It the prototype and tranfeript
be exactly alike ; if there be nothing in the one'which
is not in the other ; we may call the latter a reprefenta-
tion, a copy, a draught, or a pitlure, of the former 5 but
we never call it an imitation.
Sect. V. Of Arrangement, Unity, Digrefons.—Further
remarks on Nature in Poetry.
I. I HE origin of nations, and the beginnings of great
events, are little known, and feldom intereding •, whence
H<nv a firft part of every hiftorA compared with Ae fequel,
poem ought18 fol«ewhat dry and tedious. But a poet mud, even in
ta begin. the beginning of his work, intered the readers, and raife
high expedation ; not by an affeded pomp of dyle, far
lei’s by ample promifes or bold profeffions ; but by fet-
tmg immeuiately before them fome incident, driking
enough to raife curiofity, in regard both to its caufes
and to its confequences. He mud therefore take up his
dory, not at the beginning, but in the middle ; or ra¬
ther, to prevent tile work from being too long, as near
the end as poffible 5 and afterwards take fome proper op¬
portunity to inform us of the preceding events,‘in the
Way of narrative, or by converfation of the periens in¬
troduced, or by diort and natural digreflions.
The adion of both the I/iad and Odyfey begins about
fix weeks before its conclufion ; although th<T principal
3
TRY. Part T.
events of the war of Trey are to be found in the former;Of Hoet.cal
and the adventures of a ten years voyage, followed by Arrange-
the fupprefiion of a dangerous domedic enemy, in the
latter. One of the fird things mentioned by Homer in '
the Iliad, is a plague, which Apollo in anger fent into
the Grecian army commanded by Agamemnon and now
encamped before Iroy. Who this Agamemnon was,
and who the Grecians were ; for what reafon they had
come hither ; how long the liege had laded j what me¬
morable aftions had been already performed •, and in
what condition both parties now were :—all this, and
much more, we loon learn from occafional hints and
converfations interfperfed through the poem.
In tne Atne/d, which, though it comprehends the
Iran fa ft ions of feven years, opens within a few months
of the concluding event, we are fird prefented with a
view of the Trojan fleet at fea, and nolefs a perfon than
Juno intereding herfelf to raife a dorm for their dedruc-
tion. .1 nis excites a curiofity to know fomething fur-
thf i . who thefe 1 rojans were, whence they had come,
and whither they were bound ; why they had left their
owl\ country, and what had befallen them fince they
veit it. On all thefe points, the poet, without quitting
the track of his narrative, loon gives the fulled informa¬
tion . I he dorm riles; the Trojans are driven to A-
fiica, and hofpitably received by the queen of the coun¬
try ^ at whole defire their commander relates his adven¬
tures.
I he a ft ion of Paradife I.0JI commences not many
days befet e Adam and Eve are expelled from the gar¬
den of Eden, which is the concluding event. This
poem, as its plan is incomparably more fublime and more
important than that of either the liiad or FEneid, opens
with a far more intereding feene : a multitude of angels
and archangels Unit up in a region of torment and dark-
nefs, and rolling on a lake of unquenchable fire. Who
thefe angels are, and what brought them into this mi-
ferable condition, we naturally wilh to know j and the
poet in due time informs us; partly from the converfa¬
tion of the fiends themfelves ; and more particularly by
Ae mouth of a happy Ipirit, fent from heaven to caution
tlic father and mother of mankind againft temptation,
and confirm their good refolutions by unfolding the
dreadful effefts of impiety and difobedience.
TA's poetical arrangement of events, fo different from Beattie,
the xiidorical, has other advantages befides thofe arifingut fupra.
from brevity and compaftnefs of detail : it is obvioufly 3^
more affecting to the fancy, and more alarming to the^eaJVtfn‘
paliions ^ and, being more iuitable to the order and the po^ticai ar.
manner, in which the aflions of other men ftrike our rangement,
fenfes, is a more.exafl imitation of human affairs. I
hear a fudden noife in the fixeet, and run to fee what is
the matter. An infurreftion has happened, a great
mulntude is brought together, and fomething very im¬
portant is going forward. The feene before me is the
firtt thing that engages my attention 5 and is in itfelf fa
interefting, that for a moment or two I look at it in fi-
lence and wonder. By and by, when I get time for re¬
flexion, I begin to inquire into the caufe of all this tu¬
mult,. and what it is the people would be at 5 and one
who is better informed than I, explains the affair from
the beginning ; or perhaps I make this out for myfelf,
from the w-ords and aftions of the perfons principally
concerned. . This is a fort of piXure of poetical arrange¬
ment, both in epic and dramatic compofition j and this
„ plan
fait I.
Of i'cetical
Arrange-
wient, c.
. 3S
Uniiy of
tlefigw ne-
ceiiary to
the higher
poetry.
* At i/1
Pcet:§ 8.
f Nor. Ar.
Feet. v. 15
Uc.
3^
The pro-
] riety of
digre (lions
aiid epi-
fodes de¬
pends upon
. 37
their con¬
nection
with the
fubject of
the poem.
P O E
j lan lias 'been followed in narrative odes and ballads
both ancient and modern.—The liiftorian purfues a
different method. He begins perhaps with an account
ot the manners of a certain age, and of the political
coniUtutvon or a certain country 5 then introduces a par¬
ticular perfon, gives the fiory of his birth, connexions,
private character, puriuit's, difappointments, and of the
events that premoted his views, and brought him ac¬
quainted with other turbulent fpirils like himfelf; and
lo proceeds, unfolding, according to the order of time,
the caules, principles, and progrefs of the confpiracy,
if that be the iubjecl which he undertakes to illuffrate.
It cannot be denied, that this latter method is more fa¬
vourable to calm information : but the former, compa¬
red with it, will be found to have all the advantages al¬
ready fpecided, and to be more effeclually productive of
that mental pleaiure which depends cn the paflions and
imaginalion.
II. If a work have no determinate end, it has no
meaning •, and if it have many ends, it will dill raff by
its multiplicity. Unity of defign, therefore, belongs in
feme meaiure to all compofitions, whether in verie or
'profe. But to iome it is more effential than to-others $
and to none fo much as in the higher poetiy. In cer¬
tain kinds of hiftory, there is unity fufficient if all the
events recorded be referred to one perfon ; in others, if
to one period of time, or to one people, or even to the
inhabitants of one and the fame planet. But it is not
enough that the fub ecf of a poetical fable be the ex¬
ploits of one perfon ; for thefe may be of various and
even of oppofite forts and tendencies, and take up longer
time than the nature of poetry can admit :—far lefs can
a tegular poem comprehend the affairs of one period or
of one people :—it mull be limited to one great aXion
or event, to the illuftration of which all the fubordinate
events muff contribute j and thefe muiV be fo conneXed
with one another, as well as with the poet’s general
purpofe, that one cannot be changed, tranfpofed, or
taken away, without affeXing the confillehce and liabi¬
lity of the whole*. In iifelf an incident may be in-
terelling, a charaXcr well drawn, a defeription beauti¬
ful j and yet, if it disfigure the general plan, or if it cb-
flruX or encumber the main aXion, inflead of helping it
forward, a correX ar ill would confider it but as a gaudy
fuperfluity or fplendid deformity 5 like a piece of fcarlet
cloth fewed upon a garment of a different colour f.
• Not that all the parts of the fable either are, or can be,
equally eifential. Many deferiptions and thoughts, of
little conlequence to the plan, may be admitted for the
fake of variety ) and the poet may, as well as the hido-
rian and philofopher, drop his fubjeX for a time, in or¬
der to take up an affeXing or inflruXive digreffion.
III. The doXrine of poetical digreffions and epifodes
has been largely treated by the critics. We fliall here
only remark, that, in eftimating their propriety, three
things are to be attended to :—their conneXion with the
fable or fubjeX ; their own peculiar excellence j and
their fubferviency to the poet’s defign.
(1.) Thofe digreffions that both arife from and termi¬
nate in the fubjeX, like the epifode of the angel Ra¬
phael in Paradife Loll, and the tranfition to the death
of Crefar and the civil wars in the firft book of the
Georgic, are the moft artful, and if fuitably executed
claim the higheft praife :—thofe that arife from, but do
not terminate in, the fubjeX, are perhaps fecond in the
T It Y. . . . ^ . 767
order of merit; Hire t&e dory op Dido in the/Lineal, Of Poetical
Arrange¬
ment, &c,.
and the encomium on a country life in the fecond book
of the Georgic : thofe come next that terminate in, but
do not rife from, the fable •, of which there are feyeral
in the third book of the /Eneid, and in the Odyffey :—
and thofe that neither terminate in the fable nor rile
, from it are the lead artful $ and if they be long, cannot
efcape cenfure, unlefs their beauty be very great. 38
But (2.) we are willing to excule a beautiful epifode their own
at whatever expence to the fubjeX: it may be introduced, cx~
They who can blame Virgil for obtruding upon them ^ ’
the charming tale of Orpheus and Euridicc in the fourth
Georgic, or Milton for the apoftrophe to light in the
beginning of his third bock, ought to forfeit all title to ,
the perufal of good poetry j for of fuch divine drains
one would rather be the author than of all the books of
crlticifm in the world. Vet frill it is better that an
epifode poffefs the beauty of connection, together with
its own intrinfic elegance, than this without the other. 39
Moreover, in judging of .the propriety of epifodes and their fub-
other fimtlar contrivances, it may be expedient to attend‘e“cpfsto
(3.) to the defign of the poet, as diflinguiffied from the(|cr1|n.
fable or fubjeX of the poem. The great defign, for ex¬
ample, of Virgil, was to interelt his countrymen in a
poem written with a view to reconcile them to the per¬
fon and government of Auguftus. Whatever, therefore,
in the poem tends to promote this defign, even though it
fhould in feme degree hurt the contexture of the fable,
is really a proof of the poet’s judgement; and may be
not only allowed, but applauded.—T he progrefs of the
aXion of the /Eneid may feem to be too long obftruXed
in one place by the ftory of Dido, which, though it
rifes from the preceding part of the poem, has no influ¬
ence upon the fequel j and, ill another, by the epifode
of Cacus, which, without injury to the fable, might
have been omitted altogether. Vet thefe epifodes, in*
terefling as they are to us and all mankind becaufe cf
the tranfeendant merit of the poetry, mull have beat
ffiil more interefting to the Romans becaufe of their
conneXion with the Roman affairs 5 for the one accounts
poetically for their wars with Carthage j and the other
not only explains feme of their religious ceremonies, but
alfo gives a mofl charming rural piXure of thole hills and
valleys in the neighbourhood of the Tiber, on which, in
after times, their majeflic city was fated to Hand.—And
if we conlider, that the defign of Homer’s Iliad was not
only to ffiow the fatal effeXs of diffenflon among confe¬
derates, but alfo to immortalize his country, and cele¬
brate the moft diftinguiflied families in it, we fliall be
inclined to think more favourably than critics generally
do of fome of his Jong fpeeches and digreffions \ which,
though to us they may feen) trivial, mull have been very
interefting to his countrymen on account of the genealo¬
gies and private hiftory recorded in them.—Shakeipeare’s
hiftorical plays, confidered as dramatic fables, and tried
by the law’s of tragedy and comedy, appear very rude
compofitions j but if we attend to the poet’s defign (as
the elegant critic % has with equal truth and beauty ex- f FJTayson
plained it), we fhall be forced to admire bis judgementwrit-
in the general conduX: of thofe pieces, as well as un-
equalled fuccefs in the execution of particular parts. gShake-
There is yet another point of view in which thefe <&-ff,eare,
greffiens may be confidered. If they tend to elucidateP* $5•
any important charaXer, or to introduce any interefting
event not other wife within the ccmpafs of the poem, or
. tQ
768 POE
Of Poetical to give an amiable dxfplay of any particular virtue, they
me'nt r&T’’ ma^ no^ to our pardon only, but even to our
> admiration, however loofely they may hang upon the
fable. All thefe three ends are effected by that moft
beautiful epifede of He&or and Andromache in the
fixth book of the Iliad j and the two laft, by the no lefs
beautiful one of Euryalus and Nifus in the ninth book of
the Aineid.
ii Arift.
Poet.
§ Martial.
40
Nature al¬
ways to be
improved
by the poet,
though
41
when poe¬
try falls
fhort of
this per¬
fection it
may have
great me¬
rit ia other
Tefpeds.
IV. And now, from the pofition formerly eftablilhed,
that the end of this divine art is to give pleafure, it has
been endeavoured to prove, that, whether in difplaying
the appearances of the material univerfe, or in imitating
the workings of the human mind, and the varieties of
human character, or in arranging and combining into
one whole the feveral incidents and parts w7hereof his
fable confifts,—the aim of the poet muff; be to copy
irature, not as it is, but in that Hate of perfection in
which, confiftently with the particular genius of the
work, and the laws of veriffmilitude, it may be fuppo-
fed to be.
Such, in general, is the nature of that poetry wdiich
is intended to raife admiration, pity, and other ferious
emotions. But in this art, as in all others, there are
different degrees of excellence 5 and we have hitherto
direCted our view chiefly to the highelt. All ferious
poets are not equally folicitous to improve nature. Eu¬
ripides is faid to have reprefented men as they w?ere $
Sophocles, more poetically, as they fliould or might
be jj. Theocritus in his Idyls, and Spenfer in his Shep¬
herd’s Calendar, give us language and fentiments more
nearly approaching thofe of the Rus verum et barba-
rum §, than wdiat wre meet with in the Paftorals of Vir¬
gil and Pope. In the hiftorical drama, human charac¬
ters and events muft be according to hiltorical truth, or
at leaft not fo remote from it as to lead into any import¬
ant mifapprehenflon of fad. And in the hiftorical epic
poem, fuch as the Pharfalia of Lucan, and the Cam¬
paign of Addifon, the hiftorical arrangement is preferred
to the poetical, as being nearer the truth. Yet nature
is a little improved even in thefe poems. The perfons
in Shakefpeare’s hiftorical plays, and the heroes of the
Pharfalia, talk in verfe, and fuitably to their charafters,
and with a readinefs, beauty, and harmony of expref-
fton, not to be met with in real life, nor even in hiftory:
fpeeches are invented, and, to heighten the defcrip-
tion, circumftances added, wdth great latitude: real
events are rendered more compaft and more ftriCily de¬
pendent upon one another 5 and fictitious ones brought
in, to elucidate human characters and diverfify the nar¬
ration.
The more poetry improves nature, by copying after
general ideas collected from extenfive obfervation, the
more it partakes (according to Ariftotle) of the nature
of philofophy •, the greater ftretch of fancy and of obfer¬
vation it requires in the artift, tbe better chance it has
to be univerfally agreeable.
Yet poetry, when it falls fhort of this perfection, may
have great merit as an inftrutnent of both inftruCtion
and pleafure. To moft men, fimple unadorned nature
is, at certain times, and in certain compofitions, more
agreeable than the moft elaborate improvements of art j
as a plain fhort period, without modulation, gives a
pleafing variety to a difcourfe. Many fuch portraits of
fimple nature there are in the fubordinate parts both of
4
TRY. Parti.
Homer’s and of Virgil’s poetry : and an excellent effeCt Of Poetical
they have in giving probability to the fiCtion, as well as Language^
in gratifying the reader’s fancy with images diftinCl and ~
lively, and eafily comprehended. The hiftoricai plays
of Shakefpeare raife not our pity and terror to fuch a
height as Lear, Macbeth, or Othello 5 but they intereft
and inftruCl us greatly notwithftanding. The rudeft of
the eclogues of Theocritus, or even of Spenfer, have by
fome authors been extolled above thofe of Virgil, be-
caufe more like real life. Nay, Corneille is known to
have preferred the Pharfalia to the /Eneid, perhaps
from its being nearer tbe truth, or perhaps from the fu-
blime fentiments of ftoical morality fo forcibly and fo
oftentjitiouily difplayed in it.
Poets may refine upon nature too much as well as to®
little 5 for affeftation and rufticity are equally remote
from true elegance. The ftyle and fentiments of comedy
fhould no doubt be more correCt and more pointed than
thofe of the moft polite converfation : but to make every
footman a wdt, and every gentleman and lady an epi-
grammatift, as Congreve has done, is an exceflive and
faulty refinement. The proper medium has been hit by
Menander and Terence, by Shakefpeare in his happier
feenes, and by Garrick, Cumberland, and fome others
of late renown. To deferibe tbe paffion of love with as
little delicacy as fome men fpeak of it wrould be unpar¬
donable ; but to transform it into mere Platonic adora¬
tion is to run into another extreme, lefs criminal indeed,
but too remote from univerfal truth to be univerfally in-
terefting. To the former extreme Ovid inclines, and
Petrarch and his imitators to the latter. Virgil has hap¬
pily avoided both : but Milton has painted this paffion
as diftinCl from all others, writh fuch peculiar truth and
beauty, that we cannot think Voltaire’s encomium too
high, when he fays, that love in all other poetry feems
a weaknefs, but in Paradife Loft a virtue. There are
many good ftrokes of nature in Ramfay’s Gentle Shep¬
herd but the author’s paffion for the rus verum betrays
him into fome indelicacies : a cenfure that falls with
greater weight upon Theoci4tus, who is often abfolutely
indecent. The Italian paftoral of Taflb and Guarini,
and the French of Fontenelle, run into the oppofite ex¬
treme (though in fome parts beautifully fimple), and dif-
play a fyftem of rural manners fo quaint and affeCted as
to outrage all probability. In fine, though mediocrity
of execution in poetry be allowed to deferve the doom
pronounced upon it by Horace j yet it is true, notwith¬
ftanding, that in this art, as in many other good things,
the point of excellence lies in a middle between two
extremes \ and has been reached by tbofe only who
fought to improve nature as far as the genius of their
work would permit, keeping at an equal diftance from
rufticity on the one hand, and affefted elegance on the
other.
Sect. VI. Of Poetical Language.
Words in poetry are chofen, firft, for their fenfe; Words in
and, fecondly, for their found. That the firft of thefe poetry to fc6
grounds of choice is the more excellent nobody can dc-^(°.^ei°f
ny. He who in literary matters prefers found to fenfe an(j for
is a fool. Yet found is to be attended to even in profe,their fcua^
and in verfe demands particular attention. V/e ftiall
confider poetical language, firft, as SIGNIFICANT , and,
fecondly, as susceptible of harmony.
$
POE
Part I.
Of Poetical
Language. ^ x> Of Poetical Language conjidcred as SIGNIFICANT.
If, as it lias been endeavoured to prove, poetry be
imitative of nature, poetical ficlions of real events, poeti¬
cal images of real appearances in the vilible creation,
and poetical perfonages of real human charadlers ; it
would feem to follow, that the language of poetry muft
be an imitation of the language of nature.
According to Dr Beattie *, that language is natural
which is lulled to the fpeaker’s condition, chai after, a.id
circumftances. And as, for the moil part, the images
and fentiments of ferious poetry are copied from the
images and ientiments, not of real, but of improved,
nature ; fo the language of ferious poetry muft (as hint¬
ed already be a tranfeript, not of the real language of
nature, which is often diffonant and rude, but ot natuial
language improved as far as may be confiftent with pio-
a? iai <*a bability, and with the fuppofed charafter of the fpeaker.
may be con- jf this be not the cafe, if the language of poetry be luch
fiftent with Qj-^y we hear in converfation or read in hiftory, it
probability, Jnftead Qf delight, bring difappointment: bccaufe
it will fall Ihort of what wTe expeft from an art wdiich is
recommended rather by its pleafurable qualities than by
its intrinfic utility j and to which, in order to render it
plealing, we grant higher privileges than to any other
kind of literary compolition, or any other mode of hu¬
man language.
The next' inquiry muft therefore be, “ What are thole
improvements that peculiarly belong to the language of
poetry ?” And thefe may be comprehended under twm
heads; poetical words, and tropes and figures.
4,3
The lan¬
guage of
poetry an
imitation
of the lan¬
guage of
nature,
* Effays,
Part ii.
chap. i.
44
improved
f^r AS
Art. I. Of Poetical Words.
One mods of improvement peculiar to poetical diftion
refults from the ufe of thofe words and phrafes which,
becaufe they rarely occur in profe, and frequently in
verfe, are by the grammarian and lexicographer termed
All lan- poetical. In thefe fome languages abound more than
guages others •, but no language perhaps is altogether without
have words and perhaps no language can be fo in which any
pecuhar to numbcr of good poems have been written : for poetry is
^ ^ ^ better remembered than profe, elpecially by poetical au¬
thors, who will always be apt to instate the phrafeology
of thofe they have been accuftomed to read and admire ;
and thus, in the works of poets down through fucceffive
generations, certain phrafes may have been conveyed,
which, though originally perhaps in common ufe,. are
nowr confined to poetical compolition. Profe writers
are not fo apt to imitate one another, at leaft in words
and phrafes, both becaufe they do not fo well remember
one another’s phrafeology, and alio becaufe their lan¬
guage is lefs artificial, and muft not, if they would make
it eafy and flowing (without which it cannot be elegant),
depart effentially from the ftyle of correft converfation.
Poets, too, on account of the greater difficulty of their
numbers, have, both in the choice and in the arrange¬
ment of words, a better claim to indulgence, and hand
more in need of a diferetionary power.
The language of Idomer differs materially from what
was written and fpoken in Greece in the days of So¬
crates. It differs in the mode of infleftion, it differs in
the fyntax, it differs even in the words : fo that one
mielit read Idomer with eafe who could not read ^\eno-
phon •, or Xenophon, without being able to read Ho-
VOL. XVI. Part II.
TRY- 769
mer. Yet we cannot believe that Homer, or the frrft Of Poetical
Greek poet who wrote in his ftyle, would make choice .
of a dialeft quite different from what was intelligible in
his own time : for poets have in all ages written witn a
view to be read, and to be read with plealure j which
they could riot be if their diftion were hard to be un-
derftood. It is more reafonable to fuppofe that the lan¬
guage of Homer is according to fome ancient dialect,
which, though not perhaps in familiar ufe among the
Greeks at the time he wrote, was however intelligible.
From the Homeric to the Socratic age, a period had
elapfed of no lefs than 400 years; during which the
ftyle both of difeourfe and of writing muft have under¬
gone great alterations. Ybt the Iliad continued the
itandard of heroic poetry, and was confidered as the
very perfeftion of poetical language \ notvvithftanding
that feme words in it were become fo antiquated, or io
ambiguous, that Ariftotle himfelf ieems to have been
fomewhat doubtful in regard to their meaning f. And t Poetic.
if Chaucer’s merit as a poet had been as great as Ho-caP-35-
mer’s, and the Englifti tongue under Edward III. as
perfeft as the Greek was in the fecond century after the
Trojan war, the ftyle of Chaucer would prooably have
been our model for poetical diftion at this day ; even as
Petrarch, his contemporary, is ftill imitated by the belt
poets of Italy. . . •
The rudenefs of the ftyle of Ennius has been imputed
by the old critics to his having copied too clofely the
dialeft of common life. But this appears to be a mif-
take. For if we compare the fragments of that author
with the comedies of Plautus, who flourifhed in the fame
age, and whofe language was certainly copied from that
of common life, we (hall be ftruck with an air of anti¬
quity in the former that is not in the latiei. Ennius,
no doubt, like moft other fublime poets, affefted fome-
thing of the antique in his expreflion : and many of his
words and phrafes, not adopted by any profe-writer now
extant, are to be found in Lucretius and V irgil, and 46
were by them tranfmitted to fucceeding poets. Thefe The poeti-
form part of the Homan poetical dialeft ; which appears
from the writings of V irgil, where we have it in pe.fec; from tiiar
tion, to have been very copious. The ftyle of this0fprofe.
charming poet is indeed fo different fiom pro;e, and is
altogether fo peculiar, that it is perhaps impoffible to
analyfe it on the common principles of Latin giammc^r.
And yet no author can be more perfpicuous or more ex-
preffive } notwithftanding the frequency 01 Grecifm in
his fyntax, and his love of old words, which he, in the
judgement of Quintilian, knew better than any othci
man how to improve into decoration ||. _ ii Injht.
The poetical dialeft of modem Italy is fo different v-a. 3-J 3-
from the profaic, that perfons who can read the hifto-
rians, and even fpeak with tolerable fluency tne lan¬
guage of that country, may yet find it difficult to con-,
ft rue a page of Petrarch or Taffo. Yet it is not pro¬
bable, that Petrarch, whofe works are a ftandard of the
Italian poetical diftion §, made any material innova-§ Ficeude
tions ki his native tongue. It is rather, probable that
he wrote it nearly as it was fpoken in his time,, that is, Denina^
in the 1 4th century } omitting only harfh combinations, cap_ ^
and taking that liberty which Homer probably, and
Viroil certainly, took before him, of reviving iuch old,
but not obfolete expreffions, as feemed peculiaily figni-
ficant and melodious; and polifhing his ftyle to that de¬
gree of elegance which human fpeech, without beco-
5 5 E ming
7?o 'POE
of Poetical mirig unnatural, may admit o^, and which the genius of
*■ ^ ° d ’ . FoetlT» as an art fubfervient to pleafure, may be
thought to require.
The French poetry in general is diftinguifhed from
profe rather by the rhirce and the meafure, than by any
nld or uncommon phrafeology. Yet the French, on
certain fubjedts, imitate the ftyle of their old poets, of
Marot in particular ; and may therefore be (aid to have
fomething of a poetical dialedt, though far lefs exlenfive
than the Italian, or even than the Engliih. And it
may be prefumed, that in future ages they will have
more of this dialeft than they have at prefent. This
may be inferred from the very uncommon merit of fome
of tiieir late poets, particularly Boileau and La Fon¬
taine, who, in their refpeftive departments, will conti¬
nue to be imitated, when the preient modes of French
prefe are greatly changed : an event that, for all the
pains they take to preferve their language, mud; inevita¬
bly happen, and whereof there are not wanting fome
prefages already.
The Lnglifh poetical dialect is not characterifed by
any peculiarities of inflection, nor by any great latitude
in the ufe of foreign idioms. More copious it is, how¬
ever, than one would at flrft imagine *, as may appear
_ Irom the following fpecimen and obfervations.
Thrafes in (i.) A few Greek and Latin idioms are common
Englifh in Lnglifh poetry, which are feldom or never to be met
poetry not vdth in profe. (fejENCHED OF hope. Shakefpeare.—
-jfual in Shorn OF HIS beams. Milton.—Created thing NOR
VAEUED HE NOR shun’d. Milton.—"’Tis thus we riot,
'while who sow it starve. Pope.—This day EE
BREAD AND PEACE MY EOT. Pope.— INTO WHAT PIT
thou see’st From what height fallen. Milton.
lie deceived the mother of mankind. WHAT TIME HIS
PRIDE Had CAST him out of heaven. Milton.—Some
of thefe, with others to be found in Milton, feem to
have been adopted for the fake of brevity, which in the
poeiical tongue is indifpenfable. For the fame reafon,
perhaps the articles a and the are fomelimes omitted by
our poets, though Id's frequently in ferious than bur-
lefque compofition. In Englifli, the adjedlive gene¬
rally goes before the fubftantive, the nominative before
the verb, and the a dive verb before (what rve call) the
accufative. Exceptions, however, to this rule, are not
uncommon even in profe. But in poetry they are more
frequent. Their homely joys, and destiny obscure.
Isoxv fades the glimmering landfcapc on the fght; and
ell the air a folemn fillnejs holds. In general, that verfi-
fication may be lefs difficult, and the cadence more uni-
iormly pleading •, and fomel’mes, too, in order to give
energy to exprefiion, or vivacity to an image,—the
Engliffi poet is permitted to take much greater liberties
than tlie profe-writer, in arranging his words, and mo¬
dulating his lines and periods. Examples may be leen
in every page of Paradife Loft.
(2.) Some of our poetical words take an additional
fyllable, that they may fuit the verfe the better j as,
c!if part, difain, difport, affright, enchain, for part, (lain,
fport, fright, chain. Others feem to be nothing elfe
than common words made fliorter, for the convenience
of the verfifier. Such are, auxiliar, fukhinar, trump,
vale, part, clime, fubmifs, frolic, plain, drear, dread,
helm, morn, mead, eve and even, gan, illume and illu-
ynine, ope, hoar, bide, fwage, [cape ; for auxiliary, fublu-
P.ary, trumpet, valley, depart, climate, fubmiffive, frolic-
T R Y.
Part I.
fome, complain, dreary, dreadful, helmet, tncrnlng, fnea- Of Poetical
dow, evening, began or began to, illuminate, open, hoa- WorcJs-
ry, abide, affuage, efcape. Of fome of thefe the fhort '
form is the more ancient. In Scotland, even, morn,
bide, fwage, are ftiil in vulgar ufe ; but morn, except
when contradiflinguifhed to even, is fynonymous, not
with morning (as in the Engliih poetical dialed!), but
with morrow. The Latin poets, in a way fomewhat
fimilar, and perhaps for a limilar reafon, fhortened fun-
damentum, tutamentum, munimentum, &c. into funda-
men, tutamen, munimen.
(3.) Of the following words, which are now almofl:
peculiar to poetry, the greater part are ancient, and
were once no doubt in common ufe in England, as
many of them ftiil are in Scotland. Afeld, amain, an¬
noy (a noun), anon, aye (ever), belief, blithe, brand
(fvvord), bridal, carol, dame (lady), feally, fell (an ad-
je6Hve),ytf//tf«?, gore, fwf (army), lambkin,late (of late),
lay (poem), lea, glade, gleam, hurl, lore, meed, orifons,
plod (to travel laborioufly), ringlet, rue (a verb) ruth,
ruthlefs,fojourn (a noun), finite, [peed (an adtive verb),
five (except), fpray (twig), feed,frain {[ox\f),f rand,
[wain, thrall, thrill, trail (a verb), troll, wail, welter,
warble, wayward, %voo, the while (in the mean time),
yon, of yore.
(4.) Thefe that follow are alfo poetical ; but, fo far
as appears, were never in common ufe. Appal, arrowy,
attune, battailous, brecet-y, car (chariot), clarion, cates,
courfer, darkling, flicker, floweret, emblaze, gainjh, cir¬
clet, impearl, nightly, jwifelefls, pinion (wing), Jhadowif,
flumberous,flreamy, troublous, wilder (a xtx\T),Jhrill (a
verb), Jhook (ffiaken), madding, view lefs.—The follow¬
ing, too, derived from the Greek and Latin, feem pe¬
culiar to poetry. Clang, clangor, choral, bland, boreal,
dire, enflanguined, ire, ireful, lave (to walk), nymph, (la-
dy, girl), orient, panoply, philomel, infuriate, jocund, ra¬
diant, rapt, redolent, refulgent, verdant, vernal, ’zephyr,
•zone xA\t),fjIvan, fuflvfe.
(5.) In molt languages, the rapidity of pronuncia¬
tion abbreviates fome of the commonelt words, or even
joins two, or perhaps more, of them, into one} and
fome of thofe abbreviated forms find admiffion into wri¬
ting. The Engliffi language was quite disfigured by
them in the end of the laft century 5 but Swift, by his
fatire and example, brought them into difreputc : and,
though fome of them be retained in converfation, as
don't, fhaift, can't, they are now avoided in folemn
Lyle j and by elegant writers in general, except where
the colloquial dialed! is imitated, as in comedy. ‘‘Tis
and ‘‘twas, fince the time of Shaftefbury, feem to have
been daily lofing credit, at leal! in profe j but Hill have
a place in poetry, perhaps becaufe they contribute to
concifenefs. "‘Twas on a lofty vafe's fide. Gray.—'T'is
true, ’’tis certain, man, though dead, retains part of him-
fclf Pope. In verfe too, over may be Ihortened into
cVr, (which is the Scotch, and probably was the old
Engliffi, pronunciation); never into ne'er ; and from the
and to, when they go before a word beginning with a
vowel, the final letter is fomeiimes cut off. O’er hills,
o'er dales, o'er crags, o'er rocks they go. Pope.— Where'er
/he turns, the Graces homage pay. And all that beauty,
all that wealth e'er gave. Rich with the fpoils of time
did ne'er unroll. Gray.—T'alarm th' eternal midnight
of the grave. Thefe abbreviations are now peculiar
to the poetical tongue? but not neceffary to it. They
foroe times
Part I! POE
Of i'oetkal fometimes promote brevity, and render verification lefs
Words, difficult.
'V—(6.) Thofe words which are commonly called com¬
pound epithets, as rofij-fmger'd, rojy bofom'd, many twink¬
lings many-foundings rnofs-grown, bright-eyed,Jlraw-built,
fpir it fir rings incenfe-brcathing, heaven taught, love-whif-
perings lute-refounding, are alio to be confidered as part
of our poetical dialed. It is true, we have compound¬
ed adjectives in familiar ufe, as highfeafoned, well-natu¬
red, ill-bred, and innumerable others. But we fpeak of
thofe that are lefs common, that feldom occur except
.3 in poetry, and of which in profe the ufe would appear
tobeufed affected. And that they fometimes promote brevity
fparingly: and vivacity of expreflion, cannot be denied. But as
they give, when too frequent, a fiiff and finical air to
a performance } as they are not always explicit in the
fenfe, nor agreeable in the found ; as they are apt to
produce a confufion, or too great a multiplicity, ox
images; as they tend to disfigure the language, and
furniffi a pretext for endlefs innovation ; they ought to
be uled fpanngly j and thole only ufed which the prac¬
tice of popular authors has rendered familiar to the ear,
and which are in themfelves peculiarly emphatical and
harmonious.
(7.) In the transformation of nouns into verbs and
participles, our poetical dialed admits of greatei lati¬
tude than profe. Hymn, pillow, curtain, fioiy, pil¬
lar, pidure, peal, furge, cavern, honey, career, cinc¬
ture, bofom, Iphere, are common nouns j but to hymn,
to pillow, curtained, pillared, pillared, pealing, furging,
cavern'd, honied, careering, cinRured, bofomed, fphei ed,
would appear affeded in profe, and yet in verfe they
are warranted by great authorities, though it. mult be
* 7 ImT confeffed that they are cenfured by an able critic* j who
y had ffudied the Engliffi language, both poetical , and
profaic, with wonderful diligence.
Some late poets, particularly the imitators of Spen-
fer, have introduced a great variety of uncommon words,
as certes, eft loons, ne, whilom, tranimew, moil, fonc,
lofel, albe, hight, dight, pight, thews, couthful, affot,
muchel, wend,' arrear, &c. Thefe were once poetical
words, no doubt; but they are now oblolete, and to
many readers unintelligible. No man of the prefent age,
however converiant in this dialed, would naturally ex¬
press himfelf in it on any interefting emergence; or,
luppofing this natural to the antiquarian, it would ne¬
ver appear fo to the common hearer or reader. A mix¬
ture of thefe words, therefore, muff ruin the pathos of
modern language : and as they are not familial to our
ear, and plainly appear to be fought after and affeded,
will generally give a ftiffnefs to modern verfification.
Yet in fubjeds approaching to the ludicrous they may
have a good effed ; as in the Schoolmifrefi of Shenffone,
ParneTs Fairy-tale, Thomfon’s Caftle of Indolence, and
Pope’s lines in the Dunciad upon Wormius. But this
effed will be moft pleafing to thofe who have leaft occa-
fion to recur to the gloffary.
Indeed, it is not always eafy to fix the boundary be-
tween poetical and obfolete expreffions. To many readers,
T R Y, . ^
lore, meed, behef, blithe,gaudejprmj, thrall, may already O^ctical
appear antiquated ; aad to fome the ftyle of Spenfer, or , ca i
even of Chaucer, may be as intelligible as that of Dry-
den. This however we may venture to affirm, that a
word, which the majority of readers cannot underfiand
without a gloffary, may with reafon be confidered as .ob¬
folete ; and ought not to be ufed in modern compcfition,
unlefs revived, and recommended to the public ear, by
fome very eminent writer. There are but few words in
Milton, as nathlefs, tine, f ore, bojky, &c.; there are
but one or two in Dry den, fa Iffy (e) ; and in Pope,
there are none at all, which every reader of our poetry
may not be luppofed to underftand : whereas in SnaKe-
fpeare, there are many, and in Spenfer many more,, for
which one who knows Engliffi very well may be oblige*!
to confult the dictionary, ihe practice ot IWiiton, Dr^-
den, or Pope, may therefore, in almoft all cafes, be ad¬
mitted as good authority for the ufe of a poetical word.
And in them, all the words above enumerated, as poeti¬
cal, and in prefent ufe, may actually be found. And of
fuch poets as may cheofe to obferve this rule, it will.not
be faid, either that they rejeCt the judgment of Quinti¬
lian, who recommends the neweit of the old words., and
the oldefi of the new, or that they are inattentive to
Pope’s precept ;
Be not the firft by whom the new are tried,
Nor yet the laft to lay the old afide.
Ejf. on Crit. v. 335.
We muff not fuppofe that thefe poetical words ne¬
ver occur at all except in poetry. Even from conyer-
fation they are not excluded 1 and the ancient critics
allow, that they may be admitted into profe, where
they occafionally confer dignity upon a fublime fubjeCf,
or heighten the ludicrous qualities of a mean one. But
it is in poetry only where the frequent ufe of them does
not favour of affeftation.
Nor muff we fuppofe them effential to this art. Many
paffages there are ofexquifite poetry, wherein not a fingle
phrafe occurs that might not be ufed in profe. In facf,
the influence of thele words in adorning Englilh verfe is
not very extenfive. Some intluence however they have.
They ferve to render the poetical ffyle, firft, more melo¬
dious ; and, fecondly, more folemn. _ 49
Firft, They render the poetical ftyle more melodious, In which
and more eafily reducible into meafure. Words of
wieldy fize, or difficult pronunciation, are never ufed by the poetic;i}
correft poets, where they can be avoided : unlefs in their gyie more
found they have fomething imitative of the fenfe. Homer’s melodious
poetical inflexions contribute wonderfully to the fweet-
nefs of his numbers : and if the reader is pleafed to look
back to the fpecirnen above given of the Englifh poeti¬
cal dialed, he will find that the words are in general
well-founding, and fuch as may coalefce with other words,
without producing harfh combinations. Quintilian ob-
ferves, that poets, for the fake of their verfe, are indul¬
ged in many liberties, not granted to the orator, cf
lengthening, fhortening, and dividing their words *:—*
and if the Greek and Roman poets claimed tbs iridul-Jlb-*•
5E3 gence^’1*5'"'
(D) Dryden in one place (ailneid ix. verf. 1095.) ufe Falrfed 1° denote He ac-
knowledges, that this ufe of the word is an innovation j and has nothing to plead for it but his own au-honty*
and that Falfare in Italian fometimes means the fame thing.
772 POE
Ot Jr'oetica! gence from neceffity, and obtained it, the Englifh, thofe
, , of them efpecially who write in rhyme, may claim it
with better reafon ; as the words ot their language are
lefs muiical and far lets fuceptible of variety in arrange-
5o ment and fyntax.
and folemn.. Secondly, Such poetical words as are known to be
ancient have fomething venerable in their appearance,
and impart a folemnity to all around them. This re¬
mark is trom Quintilian j who adds, that they give to
a compolition that call and colour of antiquity which
in painting is lo highly valued, but-which art can never
* Lib. viii. effectually imitate*. Poetical words that are either not
aP- 3- -ancient, or not known to be fuch, have, however, a plea*-'
ding eiTect from affociation. We are accuitomed to meet
with them in fublime and elegant writing 5 and.hence ^
-they come to acquire fubiimity and elegance : Even as
the words we hear on familiar occafions come to be ac¬
counted familiar ; and as thofe that take their rife among
pick-pockets, gamblers, and gypfies, are thought too
indelicate to be ufed by any perfon of tafte or good rnan-
.ners. When one hears the following lines, which abound
in poetical words,
The breezy call of incenfe-breatbing morn,
The fwallow twittering from the draw-built Hied,
The cock’s fhrill clarion, or the echoing horn,
No more (hall roufe them from their lowly bed :
—one is as fenfible of the dignity of the language, as
one would be of the vilenefs or vulgarity of that man’s
•fpeech, who fhould prove his acquaintance with Bride¬
well, by interlarding his difcourfe with fuch terms as mill-
f See tbe doll, queer cull, or nobbing checH f j or who, in imitation
Scowidrel s of fops and gamblers, fhould on the common occafions
^Lan^ual'e'^e'ri§ beat hollow, or faving hasdijlance\.
of New- b gives dignity to perfons gives dignity to language,
market. A man of this character is one who has borne important
employments, been connefted with honourable affociates,
and never degraded himfeff by levity or immorality of
condufd. Dignified phrafes are thofe which have been
.ufed to exprels elevated fentiments, have always made
th eir appearance in elegant compofifion, and have nevej
been profaned by giving permanency or utterance to the
paflions of the vile, the giddy, or the worthlefs. And
as by an aftive old age, the dignity of fuch men is con¬
firmed and heightened ; fo the dignity of fuch words, if
they be not fuffered to fall into difufe, feldom fails to im¬
prove by length of time.
Art. II. Of Tropes and Figures.
51
Tropes and Ie it appear that, by means of figures, language may
figures r.e- . be made more plcafing and more natural than it would be
ceffary to without them ; it will follow, that to poetic language,
k°rruar'e 'w^0^e enc^ 15 to pleafe by imitating nature, figures muff
' ' 6 ’ be not only ornamental, but neceffary. It will here be
proper, therefore, firft to point out the importance and
utility of figurative language 5 fecondly, to fhow, that
figures are more necefiary to poetry in general than to
any other mode of writing.
I. As to the importance and utility of figurative expref-
fon, in making language more pleafmg and more natu¬
ral •, it may be remarked,
(1.) That tropes and figures are often receffary to
fupply the tmavoidable defers of language. When
proper words are wanting, or not recollected, or when
we do not choofe to be always repeating them, we mull:
TRY. Part I.
have recourfe to tropes and figures. When philofophers-Of Dopes
began to explain the operations of the mind, they found ancl
that moll of the words in common ufe, being* framed to
anfwer the more obvious exigencies of life, were in their C2
proper fignification applicable to matter only and its to fupply
qualities. What was to be done in this cafe ? Would die detects
they think of making a new language to exprefs theot 'in‘ljle
qualities of mind? No: that would have been ditiicuk
or imprafticable ; and granting it both practicable and '
eafy, they muft have forei'een, that nobody would read
or liiten to what was thus fpoken or written in a new
and.consequently in an unknown tongue. They there¬
fore took the language as they found it } and where-
ever1 they thought there was a fimilarity or analogy be¬
tween the qualities of the mind and the qualities ox mat¬
ter, fcrupled not to ule the names of the material quali¬
ties tropically, by applying them to the mental qualities.
Hence came the phrales folidity of judgement, warmth of
imagination, enlargement of undeiHanding, and many
others; which, though figurative, exprels the meaning
juH as ^vell as proper words would have done. In faCt,
numerous as the words in every language are, they mult
always fall fiiort of the unbounded variety of human
thoughts and perceptions. TaHes and fmelis are almoft
as numerous as the fpecies of bodies, bounds admit of
perceptible varieties that furpafs all computation, and
the feven primary colours may be diverfified without end.
If each variety of external perception were to have a
name, language would be infurmountably difficult \ nay,
if men were to appropriate a clafs of names to each par¬
ticular fenfe, they would multiply words exceedingly,
without adding any thing to the clearnefs of ipeech.
Thofe words, therefore, that in their proper fignifi¬
cation denote the objects of one fenfe, we often apply
tropically to the objefts of another, and fay, Sweet
tafle, fweet fmell, fweet found ; lharp point, ffiarp taile,
ffiarp found 3 harmony of founds, harmony of colours,
harmony of parts j foft filk, foft colour, foft found, foil
temper $ and fo in a thoufand inHances : and yet thele
words, in their tropical fignification, are not leis intelli¬
gible than in their proper one j for ffiarp tafie and lharp
found, are as expreffive as ffiarp fword 5 and harmony of
tones is not better underflood by the mufician, than har¬
mony of parts by the architedl, and harmony of colours
by the painter.
Savages, illiterate perfons, and children, have compa¬
ratively but few words in proportion to the things they
may have occafion to fpeak of; and mult therefore re¬
cur to tropes and figures more frequently than perfons
of copious elocution. A feaman, or mechanic, even
when he talks of that which does not belong to his art,
borrows his language from that which does) and this
makes his didfion figurative to a degree that is fome-
times entertaining enough. “ Death (fays a feaman in
one of Smollet’s novels) has not yet boarded my com¬
rade 5 but they have been yard-arm and yard-arm thefe
three glaffes. His farboard eye is open, but fafl jammed
in his head; and the haulyards of his under jaw have
given way.” Thefe phral'es are exaggerated*, but we
allow them to be natural, becaufe we know that illiterate
people are apt to make ufe of tropes and figures taken
froir^their own trade, even when they fpeak of things
that are very remote and incongruous. In thofe poems,
therefore, that imitate the converfation of illiterate per¬
fons, as in comedy, farce, and pafloral, fuch figures ju-
dicioully
Part I.
77.5
Of Tropes diciou{ly applied may render tire imitation more pleafing,
anc* becaufe more exacd and natural. .
, Tigares. ^ Words that are untuneable and harfh, the poet is or-
' 71 ten obliged to avoid, when perhaps he has no other way
to avoid to exprefs their meaning than by tropes and figures *,
hardmefs of and fometimeS the meafure ot his verte may oblige him
diction. reje£^ a proper word that is not harih, meiely on
account of its being too long, or too ihort, or in any
other way' unfuitabie to the rhythm, or to the rhyme.
And hence another uie of figurative language, that it
■ contributes to poetical harmony. Thus, to prejs the
■ plain, is frequently ufed to fignify to beJlain in battle;
liquid plain is put for ocean, blueferene iorjhj, zndfjlvan
reign for country life.
Tropes and (2.) Tropes and figures are favourable to delicacy,
figures fa- When the proper name of a thing is in any retpect un-
vourable to pleafant, a well chofen trope will convey the idea m luch
delicacy; a wayr as to give offence. This is agreeable, and
even neceffary, in polite converfation, and cannot be dif-
penfed with in elegant writing ot any kind. Many
words, from their being often applied to vulgar ufe, ac¬
quire a meannefs that difqualifies them for a place in le-
rious poetry ; while perhaps, under tne intiuence o a
•different fyttem of manners, the correfponding words m
another language may be elegant, or at leaft not vulgar.
When one reads Homer in the Greek, one takes no
-offence at his calling Eumeus by a name which, literally
rendered, fignifies fvoincdierd; firff, becaufe the Gieec
word is well-founding in itfelf j fecondly,- becaufe we
■have never heard it pronounced in converfation, nprcon-
fequently debafed by vulgar ufe •, and, tlurdly, becaufe
■we know, that the office denoted by it was, in the age
of Eumeus, both important and honourable. But Pope
would have been blamed, if a name fo indelicate zsfwinc-
herd had in his tranflation been applied to io eminent a
perfonage ; and therefore he. judiciouffy makes, ufe of
the trope fynecdoche, and calls him fwain * ; a word
both elegant and poetical, and not likely to lead the
reader into any miftake about the perfon fpoken of, as
his employment had been defcrioed in a preceding pa -
-fage. The fame Eumeus is laid, in the fimple but me¬
lodious language of the original, to have been making
his own ffioes when Ulyffes came to his doorq a work
'.which in thofe days the greateft heroes would often find
neceffary. This, too, the tranflator foftens by a tropi¬
cal expreffion :
Here fat Eumenus, and his cares applied,.
To form ftrong bufkins of well feafoned hide.
A hundred other examples might be quoted from this
tranflation } but thefe will explain our meaning..
There are other occafions on which the delicacy, of
fio-urative language is. Hill more needful; as in \irgil s
) account of the effefts of animal love., and of the plague
among the hearts, in the third Georgic ; where Dryden’s
ffyle, by being lefs figurative than the original,, is m one
place exceedingly filthy, and in another fliockingly ob-
fcene.
Hobbes could conftrue a Greek author ; but his {kill
in words muff have been all derived from the diaionary j
for he feems not to have known that any one articulate
found could be more agreable, or. any one phrafe more
dignified than another. In his Iliad and Odyffey, even
when he hits the author’s fenfe (which is not always the
cafe), he proves, by his choice of words, that Oj. harmo-
P O E T R Y.
ny, elegance, or energy of ilyle, he had no manner of ^
conception. And hence that work, though caned a Figure!,_
Translation of Homer, does not even deferve the name   
of poem ; becaufe it is in every refpe£f unpleafing, being
nothin" more than a fictitious narrative delivered m a
mean prole, with the additional meannefs or harih rhyme
and untuneable meafure.—Trapp underflood Virgil well
enough as a grammarian, and had a talte for his beau¬
ties :°yet his tranflation bears no refemblance to Virgil \
which is owing to the fame cauie, an imprudent choice
of words and figures, and a total want of harmony. 5S
The delicacy we here.contend for may, indeed,, both
* 0 lypy>
book xiv.
ver/41.
ine aencacy UC1C. . ^ .* d'r . however,
in converlation and in writing, be earned 100 ai. maybe car-
killing an innocent man in a duel an affair of honour, and r^C(j t:00 far.
a violation of the rights of wedlock an affair of gallantry,
is a proftitution of figurative language. Nor is it any
credit to us, that we are faid to have upwards of 40 fi¬
gurative phrafes to exprefs exceflive drinking. Lan¬
guage of this fort generally implies, that the public ab¬
horrence of fuch crimes is not fo ftrong as it ought to
be : and it is a queftion, whether even our morals might
not be improved, if we were to call thefe and iuvh like
crimes by their proper names, murder, adultery, drunken-
nefs, gluttony ; names that not only exprefs our mean¬
ing, but alio betoken our difapprobation.—As to writ¬
ing’ it cannot be denied, that even Pope himfelf, in the
excellent verfion juft now quoted, has fometimes, for the
fake of his numbers, or for fear of giving offence by too
clofe an imitation of Homer’s fimplicity,. employed tropes
and figures too quaint or too folemn for the occation.
And the finical ftyle is in part characferifed by the wri¬
ter’s diflike to literal expreflions, and affeClediy lub-
ftituting in their ftead unneceffary tropes and figures.
With thefe authors, a man’s only child muff always be
'bis only 'hope; a country maid becomes a rural beauty,
or perhaps a nymph of the groves; if flattery fing at all,
it muff be a fyren fong; the fliepherd’s flute dwindles
into an oaten reed, and his crook is exalted into nfeep-
tre; the ftlver lilies rife from their golden beds, and
languifh to the complaining gale. A young woman,
though a good Chriftian, cannot make herfelf agree¬
able ^without facrifcing to the Graces; nor hope to do
any execution among the gentle fwains, till a whole le¬
gion of Cupids, armed with flames and darts, and other
weapons, begin to difeharge from her eyes their formi¬
dable artillery. For the fake of variety, or of the verle,
fome of thefe figures may now and then find a place in
a poem ; but in profe, unlefs very fparingly ufed, they
favour of affe£fion. ,
(3.) Tropes and figures promote brevity 5 and brevity, aJ>«
united with peripicuily, is always agreeable. An ex-
ample or two will be given in the next paragraph. Sen- vity, and
timents thus delivered, and imagery, thus painted, are
readily apprehended, by the mind, make a ftrong im-
preflion upon the fancy, and remain long in the memo¬
ry •, whereas too many words, even when the meaning
is good, never fail to bring difguft and wearinefs. They
argue a debility of mind which hinders the author from
feeing his thoughts in one diftinft point of view j and
they alfo encourage a fufpicion, that there is fomething
faulty or defeftive in the matter. In the poetic ftyle,
therefore, which is addreffed to the fancy and paflions,
and intended to make a vivid, a pleafing, and a peima-
nent impreflion, brevity, and confequently tropes and
figures, are indifpeirfable. And a language will always
/
77+ POE
01 Ir®Pes be the better fulled to poetical purpofes, the more it
Figures a(^mbs this brevity j—a charafter which is more
‘ A^ ' confpicuous in the Greek and Latin than in any modern
tongue, and much lefs in the French than in the Italian
or Englifh.
contribute (4.) Tropes and figures contribute to ftrength or
to^ftrength energy of language, not only by their concifenefs, but
eftaimmlc. al'r°1 ^ conveying to the fancy ideas that are eafily com-
° 0 prehended, and make a It rang impreffion. We are
powerfully affefted with what we fee, or feel, or hear.
When a fentiment comes enforced or illuftrated by figures
taken from objects of fight, or touch, or hearing, one
thinks, as it were, that one fees, or feels, or hears, the
thing fpoken of; and thus, what in itfelf would perhaps
be obfcure, or is merely intellectual, may be made to
feize our attention and intereft our paffions almofi as ef-
fefinally as if it were an object of outward fenfc. When
Virgil calls the Scipios thunderbolts of war, he very
ftrongly expreffes in one word, and by one image, the ra¬
pidity of their victories, the noife their atchievements
made in the world, and the ruin and confternation that
attended the:; irrefiftible careen—When Homer calls
Ajax the bulwark of the Greeks, he paints with equal
brevity his vaft frze and ftrengih, the difficulty of pre¬
vailing agaimt him, and the confidence wherewith his
countrymen repofed on his valour.—When Solomon fays
of the ftrange woman, or harlot, that “ her feet go down
to death,” he lets us know, not only that her path ends
in deflruftion, but alfo, that they who accompany her
will find it eafy to go forwards to ruin, and difficult to
return to their duty.—Satan’s enormous magnitude, and
refulgent appearance, his perpendicular afcent through
a region of darknefs, and the inconceivable rapidity of
his motion, are all painted out to our fancy by Milton,
in one yery fhort fimiKtude,
Sprung upward, like—a pyramid of fire.
Par. Lof. iv. 1013.
To take in the full meaning of which figure, we muft
imagine ourfelves in chaos, and a vafl luminous body
rifing upwards, near the place where we are, fo fwiftly
as to appear a continued track of light, and leffening
loathe view according to the increafe of dillance, till it
end in a point, and then difappear 5 and all this muft be
fuppofed to ftrike our eye at one inftant. Equal to
this in propriety, though not in magnificence, is that al¬
legory of Gray,
The paths of glory lead but to the grave :
Which presents to the imagination a wide plain, where
feveral roads appear, crowded with glittering multitudes,
and iffuing from different quarters, but drawing nearer
and nearer as they advance, till they terminate in the
dark and narrow houfe, where all their glories enter in
fucceffion, and difappear for ever. When it is faid
in Scripture, of a good man who died, that he fell
afeep, what a number of ideas are at once conveyed to
our imagination, by this beautiful and expreffive figure :
As a labourer, at the dlofe of day, goes to fleep, with
the fatisfaffion of having performed his work, and with
the agreeable hope of awaking in the morning of a new
day, refreffied and cheerful j fo a good man, at the end
of life, refigns himfelf calm and contented to the will of
his Maker, with the fweet reile£Hon of having endea¬
voured to do his duty, and with the tranfporting hope
3
TRY. Parti.
of foon awaking in the regions of light, to life and hap- Of Tropes
pinefs eternal. The figure alfo fuggefts, thai to a good and r
man the tranfition from life to death is, even in the fenfa- , Flg^rer' ,
lion, no more painful, than when our faculties melt away
into the pleafing infenfibility of fleep. Satan, Hying
among the ftars, is Hud by Milton to “fail between,
worlds and worlds j” which has an elegance and force far
fuperior to the proper word fly. For by this allufion
to a ftiip, we are made to form a lively idea of his great
fize, and to conceive of his motion, that it was equable
and majeftic. Virgil ufes a happy figure to exprefir
the fize of the great wooden horfe, by means of which
the Greeks were conveyed into Troy : “ Equum divina
Palladis arte ccdiflcant." Milton is ftill bolder when
he fays,
Who would not fing for Lycidas ! he knew
Himfelf to fing, and build the lofty rhyme.
The phrafe, however, though bold, is emphatical j and
gives a noble idea of the durability of poetry, as well
as of the art and attention requifite to form a good
poem. There are hundreds of tropical expreffious in
common ufe, incomparably more energetic than any pro¬
per words of equal brevity that could be put in their
place. A cheek burning with blufties, is a trope which
at once deferibes the colour as it appears to the beholder,
and the glowing heat as it is felt by the perlbn bluffing.
Chilled with delpondence, petrified with aftoniibment,
tlwnderflruck with difagreeable and unexpected intelli¬
gence, melted with love or pity, diflUved in luxury, har¬
dened in wickednefs, foftening into remorie, inflamed With.
defire, tojfed with uncertainty, &c.—every one is fenfible
of the force of thefe and the like phrafes, and that they
muft contribute to the energy of compofition. -
(5.) Tropes and figures promote ftrength of expref-Theyare
fion 5 and are in poetry peculiarly requifite, becaufe theytkcwiie
are often more natural, and more imitative, than properthe lan"
words. In faCt, this is fo much the cafe, that it would |^e of£.
be impoffible to imitate the language of paftion without{i0T.S Pa ~
them. It is true, that when the mind is agitated, one
does not run out into allegories, or long-winded fimf-
litudes, or any of the figures that require much attention
and many words, or that tend to withdraw the fancy
from the objeCt of the paffion. Yet the language of
many paffions muft be figurative notwithftanding; be¬
caufe they roufe the fancy, and direCf it to objefts
congenial to their own nature, which diveriify the lan¬
guage of the fpeaker with a multitude of allufions.
The fancy of a very angry man, for example, prefents
to his view a train of difagreeable ideas connefted with
the paffion of anger, and tending to encourage it; and
if he fpeak without reftraint during the paroxyfm of
his rage, thofe ideas will force themfelves upon him,
and compel him to give them utterance. “ Infernal
monfter ! (he will fay),—my blood boils at him ; ho
has ufed me like a dog 5 never was man fo injured as
I have been by this barbarian. He has no more fenfe
of propriety than a done. His countenance is diabolical,
and his foul as ugly as his countenance. His heart is
cold and hard, and his refolutions dark and bloodv,” &,c.
This fpeech is wholly figurative. It is made up of meta¬
phors and hyperboles, which, with the profopopcia and
apoflrophe, are the moft paffionate of all the figures.
Lear, driven out of doors by his unnatural daughtefs,
in the midft of darknefs, thunder, and tempeft, natu¬
rally
Part I. T ° E
Of Tropes rally breaks forth (for hi's indignation is juft now raifed
to the very higheft pitch) into the following violent ex-
, clamation againft the crimes of mankind, in which almoft
every word is figurative.
and
Ti cures.
Tremble, thou wretch,
That haft within thee undivulgcd crimes
Unwhipt of juftice. Hide thee, thou bloody hand,
Thou perjur'd, and thou fimular of virtue,
rJ'hat art inceftuous. Caitiff, to pieces ftiake,
That under covert, and convenient feeming,
Haft pradlis’d on man’s life. Clofe pent-up guilts,
Hive your concealing continents, and cry
Thefe dreadful fummoners grace. King Lear.
 The vehemence of maternal love, and forrow from
the apprehenfton of lofing her child, make the Lady
Conftance utter a language that is ftrongly figurative,
though quite fuitable to the condition and charafter of
the fpeaker. The paffage is too long for a quotation,
but concludes thus:
O Lord 1 my boy, my Arthur, my fair fon,
hly life, my jov, my food, my all the world,
My widow-comfort, and my forrow’s cure. King John.
 Similar to this, and equally expreflive of comjngal
love, is that beautiful hyperbole in Homer ; where An¬
dromache, to diffuade her hulband from going out to
the battle, tells him that (lie had now no mother, father,
or brethren, all her kindred being dead, and her native
country defolate 5 and then tenderly adds,
But while my Heftor yet furvives, I fee
My father, mother, brethren, all in thee. Iliad, b. vi.
The fim- As the paffions that agitate the foul, and roufe the
pleft lan- fancy, are apt to vent themfelves in tropes and figures,
guage moft f0 thofe that deprefs the mind adopt for the moft part
utitable to a p]a;n gi&lon without any ornament : for to a dejsifted
naflions"^ mind’ wherein the imagination is generally inaftive, it
’ ‘ ’ is not probable that any great variety of ideas will pre¬
lent themfelves; and when thefe are few and familiar,
the words that exprefs them muft be fimple. As no
author equals Shakefpeare in boldnefs or variety of
figures when he copies the ftyle of thofe violent paftions
that ftimulate the fancy ; fo, when he would exhibit
the human mind in a dejefted ftate, no uninfpired writer
excels him in {implicity. The fame Lear whofe refent-
ment had impaired his undetftanding, while it broke
out in the moft boifterous language, when, after feme
medical applications, he recovers bis reafon, his rage
being now exhaufted, his pride humbled, and his fpirits
totally depreffed, fpeaks in a ftyle than which nothing
can be imagined mere fimpde or more affefhng.
Pray, do not mock me :
I am a very foolifli, fond old man,
Fourfcore and upward ; and, to deal plainly with you,
I fear I am not in my perfect mind.
Methinks I fliould know you, and know this man 5
Yet I am doubtful: for I am mainly ignorant
What place this is; and all the fkill 1 have
Ptemembers not thefe garments : nor I know not
Where I did lodge laft night. Lear, A£t iv. fc. 7.
  Defdemona, ever gentle, artlefq and fincere, (hock¬
ed at the unkindnefs of her hulband, and overcome with
T R Y; ; 775
melancholy, fpeaks a ftyle fo beautifully fimple, and Cf Trapes
fo perfectly natural, that one knows not what to fay in FWfs>
commendation of it: »«j
My mother had a maid call’d Barbara ;
She was in love, and he (he lov’d prov’d falfe,
And did forfake her. She had a long of willow 5
An old thing it was, but it exprefs’d her fortune,
And the died finging it. That fong to-night
Will not go from my mind: I have much to do,
But to go hang my head all at one fide,
And fing it like poor Barbara. Othello, A;ft xv. fc. 3.
Sometimes the imagination, even when exerted to
the utraoft, takes in but few ideas. This happens when
the attention is totally engroffed by fome very great
objetft •, admiration being one of thofe emotions that
rather fufpend the exercife of the faculties than pufti them
into aiftion. And here, too, the fimpleft language is
the moft natural 5 as when Milton fays of the Deity, 60
that he fits “ high-throned above all height.” And as and to the
this fimplicity is more fuitable to that one great exertion
which occupies the fpeaker’s mind than a more elaborate t;oni
imagery or language would have been, fo has it Hfo a
more powerful effetft in fixing and elevating the imagi¬
nation of the hearer \ for to introduce other thoughts
for the fake of iliuftrating what cannot be iliuftrated,
could anfwer no other purpofe than to draw oft the at¬
tention from the principal idea. In theie and the like
cafes, the fancy left to ilfelf will have more fatisfedlion
in purfuing at leifure its own fpeculations than in at¬
tending to thofe of others 5 as they who fee for the firft
time fome admirable obiect would choofe rather to feaft
upon it in filence, than to have their thoughts interrupt¬
ed by a long defeription from another perfon, informing
them of nothing but what they fee before them, are al¬
ready acquainted with, or may eafily conceive.
It was remarked above that the hyperbole,profopopeia,
and apojlrophe, are among the moft pallionate figures.
This deferves illuftration. 6r
1 ft, A very angry man is apt to think the injury he hyperbole
has juft received greater than it really is j and it netlic pafl-loa
proceed immediately to retaliate byword or deed, feldotil 0f a11gtrj
fails to exceed the due bounds, and to become injurious love, fear,
in his turn. The fond parent locks upon his child as a &-c-
prodigy of genius and beauty and the romantic lover
will not be perfuaded that his miftrefs has nothing fuper-
natural either in her mind or perfon. Fear, in like
manner, not only magnifies its object when real, but
even forms an objeift out of nothing, and miftakes the
iidtions of fancy for the intimations of fenfe.-—No won¬
der, then, that they who fpeak according to the impulfe
of paffion fliould fpeak hyperbolicallij ; that the angry'
man Ihould exaggerate the injury he has received, and
the vengeance lie is going to inflnft ; that the forrowful
Ihould magnify what they have loft, and tile joyful what
they have obtained ; that the lover Ihould (peak extra¬
vagantly of the beauty of his miftrefs, the corvard oi
the dangers he has encountered, and the credulous clown
of the miracles performed by the juggler. In faift,
thefe people would not do juftice to what they feel if
they did not fay more than the truth. The valiant man,
on the other hand, as naturally adopts the diminifhing
hyperbole when he fpeaks of danger j and the man ot
fenfe, when he is obliged to mention his own virtue or.
ability j becaufe it appears to him, or he is willing to
confide r
77^ POE
Of Tropes confider it, as lefs than the truth, or at heft as inconfi-
rv !, derable. Contempt ufes the fame figure •, and there-
< i fore Petruchio, affecting that path on, affects alfo the
language of it:
Thou lieft, thou thread, thou thimble,
Thou yard, three-quarters, half-yard, quarter, nail,
Thou flea, thou nit, thou winter-cricket, thou !
Brav’d in mine own houfe with a fkein of thread !
Away, thou rag, thou quantity, thou remnant !
Taming of the Shrew, Act iv. fc. I.
Tor fome pafhons confider their objects as important,
and others as unimportant. Of the former fort are
anger, love, fear, admiration, joy, forrow, pride ,j of the
latter are contempt and courage. Thofe may be faid
to fubdue the mind to the object, and thefe to fubdue
the object to the mind. And the former, wdien violent,
always magnify their objects: whence the hyperbole
called amplification, or auxefis : and the latter as con-
flantly diminith theirs; and give rife to the hyperbole
called tneiojis, or diminution.—Even when the mind can¬
not be faid to be under the influence of any violent paf-
fion, we naturally employ the fame figure when we
would imprefs another very ftrongly with any idea. “ He
is a walking fhadow : he is worn to fkin and bone ) he
has one foot in the grave and the other following —
thefe, and the like phrafes, are proved to be natural by
their frequency. By introducing great ideas, the hy¬
perbole is further ufeful in poetry as a fource of the
fublime; but when employed injudicioufly is very apt
to become ridiculous. Cow-ley makes Goliah as big us
* Davideis,the hill down which he w’as marching * 5 and tells us,
book lii. thgj when }le came into the valley he feemed to fill it,
and to overtop the neighbouring mountains (which, by
the by, feems rather to leffen the mountains and valleys
than to magnify the giant) : nay, he adds, that the fun
Parted back when he faw^ the fplendour of his arms.
This poet feems to have thought that the figure in
queftion could never be fufficiently enormous j but Quin¬
tilian would have taught him, “ Quamvis omnis hyper¬
bole ultra fidem, non tamen effe debet ultra modum.”
The reafon is, that this figure, when exceflive, betokens
rather absolute infatuation than intenfe emotion ; and
refembles the efforts of a ranting tragedian, or the ra¬
vings of an enthufiaftic declaimer, who, by putting on the
geftures and looks of a lunatic, fatisfy the difeerning
part of their audience, that, inftead of feeling ftrongly,
they have no rational feelings at all. In the valdeft
energies of nature there is a modefty which the imitative
artift wall be careful never to overftep.
Profopo- 2dly, That figure, by which things are fpoken of as
poeia, when jf they were perfons, is called profopopotia, or perfotrifea-
proper. tion. It is a bold figure, and yet is often natural. Long
acquaintance recommends to fome {hare in our affedlion
even things inanimate, as a houfe, a tree, a rock, a
mountain, a country •, and were we to leave fuch a thing
without hope of return, rve fliould be inclined to addreis
it with a farewel, as if it were a percipient creature.
Hence it was that Mary queen ot Scotland, wdien on her
return to her own kingdom, fo affeclionately bade adieu
to the country which ft e had left. “ Farew'el France,”
faid fine ; “ farewel, beloved country, wdiich I fhall ne¬
ver m ire behold !” Nay, wre find that ignorant nations
have a ftually worfliipped fuch things, or confidered them
as the haunt of certain powerful beings. Dryads and
2
try.
Part I.
hamadryads w'ere by the Greeks and Homans fuppofed
to prefide over trees and groves ; river gods and nymphs,
over ftreams and fountains 3 little deities, called Lares
and Penates, wrere believed lobe the guardians of hearths
and houfes. In Scotland there is hardly a hill remark¬
able for the beauty of its fliape, that was not in former
times thought to be the habitation of fairies. Nay, mo¬
dern as wTell as ancient fuperftition has appropriated the
wTaters to a peculiar fort of demon or goblin, and people
the very regions of death, the tombs and chai nel-houles^
with multitudes of ghofts and phantoms.—Befides, when
things inanimate make a ftrong impreflion upon us, whe¬
ther agreeable or otherwife, we are apt to addiefs them
in terms of affedlion or diflike. The failor bleffes the
plank that brought him afhore from the ILipwreck 3 ancl
the paflionate man, and fometimes even the philofopher,
will fay bitter words to the Humbling block that gave
him a fall,—Moreover, a man agitated with any interef-
tingpaffion, efpecially of long continuance, is apt to fan¬
cy that all nature fympathifes w-ith him. If he has loft
a beloved friend, he thinks the fun lefs bright than at
other times 3 and in the fighing of the winds and groves,
in the lowings of the herd, and in the murmurs of the
ftream, he feems to hear the voice of lamentation. But
when joy or hope predominate, the whole world affumes
a gay appearance. In the contemplation of every part
of nature, of every condition of mankind, of every form
of human fociety, the benevolent and the pious man, the
morofe and the cheerful, the mifer and the mifanthrope,
finds occafion to indulge his favourite paffion, and fees,
or thinks he fees, his own temper refledled back in the
aftions, fympathies, and tendencies of other things and
perfons. Our affedlions are indeed the medium through
■which we may be faid to furvey ourfelves, and every
thing elfe 3 and whatever be our inward frame, wTe are
apt to perceive a wonderful congeniality in the world
without us. And hence the fancy, wThen roufed by real
emotions, or by the pathos of compofition, is eafily re¬
conciled to thofe figures of fpeech that aferibe fympathv,
perception, and the other attributes of animal life, to
things inanimate, or even to notions merely intelleaual.
—Motion, too, bears a clofe affinity to afticn, and af-
fe£ls our imagination nearly in the fame manner 3 and
we fee a great part of nature in motion, and by its fenfi-
ble effects are led to contemplate energies innumerable.
Thefe conduft the rational mind to the Great Firft
Caufe 3 and thefe, in times of ignorance, dilpofed the
vulgar to believe in a variety of fubordinate agents em¬
ployed in producing thofe appearances that could not
otherwife be accounted for. Hence an endlefs train of
fabulous deities, and of witches, demons, fairies, genii 3
which, if they prove our reafon weak and our fancy
ftrong, prove alfo that perfonification is natural to the
human mind 3 and that a right ufe of this figure may
have a powerful effeft, in fabulous writing efpecially, to
engage our fympathy in behalf of things as well as per¬
fons : for nothing can give lafting delight to a moral be¬
ing, but that which awakens fympathy, and touches the
heart 3 and though it be true that we fympathife in force
degree even with inanimate things, yet what has, or is
fuppofed to have, life, calls forth a more fincere and
more permanent fellow-feeling.-—-Let it be obferved fur¬
ther, that to awTaken our fympathetic feelings, a lively
conception of their objeft is neceffary. This indeed is
true of almoft all our emotions 3 their keennefs is in pro¬
portion
Of Tropes
ar d
Figures.
Part I.
POE
Of Tropes portion to the vivacity of the perceptions that excite
*nd them. Diftrefs that we fee is more affetting than what
. F*g^reii- we only [iear 0£ * j a perufal of the gayeft feenes in a
* Hor. Ar. comedy does not roufe the mind fo effectually as the pre-
foef.v. rSo. fence of a cheerful companion 5 and the death of a friend
is of greater energy in producing ferioufnefs, and the con-
fideration of our latter end, than all the pathos of 'V. oung.
Of deferiptions addreffed to the fancy, thofe that are
tnoft vivid and piCturefque will generally be found to
have the moft powerful influence over our affeftions j
and thofe that exhibit perfons engaged in aftion, and
adorned with vifible infignia, give a brifker impulfe
to the faculties than fuch as convey intellectual ideas
only, or images taken from ftill life. No abftraCt notion
of time, or of love, can be fo Itriking to the fancy as
the image of an old man accoutred with a feythe, or of
a beautiful boy with wings and a bow and arrows : and
no phyliological account of frenzy could fuggeft fo vi¬
vid an idea as the poet has given us in that exquifite por¬
trait,
And moody madnefs laughing wild amid feverelt wo.
And for this reafon partly it is that the epic poet, in or¬
der to work the more effectually Upon our paflions and
imagination, refers the fecret fprings of human conduCt,
and the viciflitudes of human affairs, to the agency of
perfonified caufes } that is, to the machinery of gods and
goddeffes, angels, demons, magicians, and other power¬
ful beings. And hence, in all fublime poetry, life and
motion, with their feveral modes and attributes, are li¬
berally beftowed on thofe objeCts wherewith the author
intends that we fliould be ftrongly impreffed : feenes per¬
fectly inanimate and ftill, tending rather to diffufe a lan¬
guor over the mind than to communicate to our internal
powefs thofe lively energies without which a being ef-
fentially aCtive can never receive complete gratification.
 Laftly, fome violent paflions are peculiarly inclined to
change things into perfons. The horrors of his mind
haunted Oreftes in the fhape of furies. Confcience, in
the form of the murdered perfon, flares the murderer in
the face, and often terrifies him to diftraCHon. The fu-
perftitious man, travelling alone in the dark, miftakes a
white ftone for a ghoft, a bufti for a demon, a tree wav¬
ing with the wind for an enormous giant brandifhing a
hundred arms. The lunatic and enthufiaft converfe with
perfons who exift only in their own diftempered fancy }
and the glutton and the mifer, if they were to give ut¬
terance to all their thoughts, would often, it is prefu-
mable, fpeak, the one of his gold, the other of his bel¬
ly, not only as a perfon, but as a god,—the objeCf of
his warmeft love and moft devout regard.—More need
not be faid to prove that perfonification is natural, and
may frequently contribute to the pathos, energy, and
beauty of poetic language.
63 sdly, Apqflrophe, ar a fudden diverfion of fpeech from
Apoftmphe one perfon to another perfon or thing, is a figure
now to be nearly reiated to the former. Poets fometimes make
ufe of it, in order to help out their verfe, or merely to
give variety to their ftyle : but on thefe occafions it is
to be confidered as rather a trick of art, than an effort
of nature. It is moft natural, and moft pathetic, when
the perfon or thing to whom the apoftrophe is made,
and for whofe fake we give a new direCHon to our
fpeech, is in our eyes eminently diftinguilhed for good
or evil, or rrfifes with- us fosne fudden and powerful
VoL. XVI. Part II.
THY. 777
emotion, fuch as the hearer would acquiefce in, or at Of Tropes
leaft acknowledge to be reafonable. . But this, like the p;gUies.
other pathetic figures, muft be ufed with great prudence. ^
For if, inftead of calling forth the hearer’s fympathy, it
fliould only betray the levity of the fpeaker, or tuch wan¬
derings of his mind as neither the fubjeft nor the occa-
fion would lead one to expeCt, it will then cieale dil-
guft inftead of approbation. The orator, therefore, muit_
not attempt the paflionate apoftrophe, till the minds ol
the hearers be prepared to join in it. And every au¬
dience is not equally oblequious in this refpeCt. In the
forum of ancient Home that would have paffed for fub¬
lime and pathetic, which in the moft refpeftable ijr.Ufi^
auditories would appear ridiculous. For our ftyle oi
public fpeaking is cool and argumentative j and par¬
takes lefs of enthufiafm than the Roman did, and much
lefs than the modern French or Italian. Oi Britifli
eloquence, particularly that of the pulpit, the chief re¬
commendations are gravity and fimplicity. And it is
vain to fay, that our oratory ought\.o be more vehement,
for that matter depends on caufes, which it is not only
inexpedient, but impoflible to alter j namely, on the cl.a-
rafter and fpirit of the people, and their rational notions
in regard to religion, policy, and literature, fhe ex¬
clamations of Cicero would weigh but little in our par¬
liament j and many of thofe which vre meet with in
French fermons would not be more effedlual if attempt¬
ed in our pulpit. To fee one of our preachers, who
the moment before was a cool reafoner, a temperate
fpeaker, an humble Chriftiart, and an orthodox divine,
break out into a fudden apoftrophe to the immortal
powers, or to the walls of the church,, tends to force a
fmile, rather than a tear, from thofe among us who
refleft, that there is nothing in the fubjeft, and Ihould
be nothing in the orator, to warrant fuch wanderings of
fancy or vehemence of emotion. If he be careful to
cultivate a pure ftyle, and a grave and graceful utter¬
ance, a Britilh clergyman, who fpeaks from convidtion
the plain unaffetted words of truth and fobernefs, of be¬
nevolence and piety, will, it is believed, convey more
pathetic, as well as more permanent, impreflions to the
heart, and be more ufeful as a Chriftian teacher, than
if he were to put in pra&ice all the attitudes of Rofcius,
and all the tropes and figures of Cicero.
But where the language of paflion and enthufiafm is
permitted to difplay itfelf, whatever raifes any ftrong
emotion, whether it be animated or inanimate, abfent
or prefent, fenfible or intelle&ual, may give rife to the
apoftrophe. A man in a diftant country, fpeaking ot
the place of his birth, might naturally exclaim, “ O my
dear native land, {hall I never fee thee more !” Or, when
fome great misfortune befals him, “ Happy are ye, O
my parents, that ye are not alive to fee this.” \\ e have
a beautiful apoftrophe in the tnird book of the Aineid,
where Aineas, who is telling his ftory to Dido, happen¬
ing to mention the death of his father, makes a fudden
addrefs to him as follows :
 hie, pelagi tot tempeftatibus achis,
Heu, genitorem, omnis curee cafufque levamen,
Amitto Anchifen hie me, paler optime, feflum
Deferis, heu, tantis nequicquam erepte periclis !
This apoftrophe has a pleafing effedt. It feems to inti¬
mate, that the love which the hero bore his father was
fo great, that-wheir he mentioned him he forgot every1
5 F thinS
Of Tropes
ami
Figures.
64
Tropes
and figures
are ufeful,
as they
fuggeft
an endiefs
variety of
agreeable
ifRUges.
POE
thing elfe 5 arid, wjtliout minding his company, cne of
whom was a queen, fuddenly addreffed himfelf to that
which, though prefent only in idea, was itill a principal
objedt of lifs affedtion. An emotion fo warm and fo
realbnable cannot fail to command the lympathy of the
reader. When Michael, in the eleventh book of Pa-
radife Loft, announces to Adam and Eve the neceflity
of their immediate departure from the garden of Eden,
the poet’s art in preferving the decorum of the two cha-
rafters is very remarkable. Pierced to the heart at the
thought cf leaving that happy place, Eve, in all the
violence of ungovernable furrow, break's forth into a pa¬
thetic apoftrophe to Paradife, to the Rowers the had
reared, and to the nuptial bower fhe had adorned. A-
dam makes no addrefs to the walks, the trees, or the
Rowers cf the garden, the lofs whereof did not fo much
Allidl him; but, in Ins reply to the Archangel, expref-
!es, without a figure, his regret for being banilhcd from
a place where he had been fo often honoured with a fen-
fiible manireflation of the divine prefence. The ufe of
the apoftrophe in the one cafe, and the omilTion of it in
the other, not only gives a beautiful variety to the flyle,
but alio marks that fuperior elevation and compofure of
mind, by which the poet had all along diltinguilhed the
char abler of Adam.—One of the fineft applications of
this figure that is anywhere to be feen, is in the fourth
book of the fame poem 5 where the author, catching by
lympathy the devotion of our firft parents, fuddenly
hrops his narrative, and joins his voice to theirs in ado¬
ring the Father of the univerfe.
Thus at their Ihady lodge arriv’d, both food,
Both turn’d, and under open Iky ador’d
The God that made both iky, air, earth, and heav’n,
Which they beheld, the moon’s refplendent globe,
And Harry pole :—Thou alfo mad’it the night,
Maker omnipotent ! and thou the dav,
Which we in our appointed work employ’d
Have finilh’d. 
Milton took the hint of this fine contrivance from a
well-known pafiage of Virgil :
Hie juvenum chorus, ille fenum ; qui carmine laudes
Herculeas et fabta ferant 5 
 ut duros mille labores
Rege fab Euryftheo, fatis Junonis iniqme,
Pertulerit:—Tu nubigenas, invibte, bimembres,
Hylasumque, Pholumque manu, tu Crefia mabtas
Prodigia. * 
The beauty arifing from diverfified compofition is the
lame in both, and very great in each. But every read¬
er mull feel, that the figure is incomparably more affebt-
ing to the mind in the imitation than in the original.
So true it is, that the moft rational emotions raile the
moft intenfe fellow-feeling; and that the apoftrophe is
then the moft empKatical, when it difplays thofe work¬
ings of human affection which are at once ardent and
well-founded.
To conclude this head : Tropes and figures, parti¬
cularly the metaphor, ftmilitude, and allegory, are further
ufeful in beautifying language, by fuggefting, together
with the thoughts effential to the fubjebt, an endiefs va¬
riety of agreeable images, for which there would be no
place, if writers were always to confine themfelves to the
proper names of things. And this beauty and variety,
T R Y. Pm I.
judicioufly applied, is fo far f.cm diftracling, that it Of Tropes
tends rather to fix the attention, and captivate the heart .ailcl
of the readers, by giving light, and life, and pathos, to Flg^rcS- f
the whole compofition. v 'r
IE That tropes and figures are more neceffary to
poetry, than to any other mode of writing, was the
fecond point propofed to be illultrated in this ieblion. c
Language, as already obferved, is then natural, when Tropes and
it is luitable to the fuppofed condition of the Ipeaker. figures
Figurative language is peculiarly fuitable to the fuppo-,nore necei'-
fed condition of the poet: becaufe figures are fuggeited ‘al-v to .
by the. fancy • and the fancy of Inm who compotes to anjothsr
poetry is more employed than that of any other author, mode of
Of all hiftoric&l, philofophical, and theological refearch- writing,
es, the object is real truth, which is fixed and perma¬
nent. The aim of rhetorical declamation (according to
Cicero) is apparent truth; which, being lefs determi¬
nate, leaves the fancy of the fpeaker more free, gives
greater fcopc to the inventive powers, and fuppiies the
materials of a more figurative phrafeology. But the
poet is fubjedl to no reftraints, but thofe of verifimili-
tude; which is ftill lefs determinate than rhetorical
truth. He feeks not to convince the judgement of his
reader by arguments of either real or apparent cogency j
he means only to pfeafe and intereft him, by an appeal
to his fenfibility and imagination. His own imagina¬
tion is therefore continually at work, ranging through
the whole of real and probable exiltence, “ glancing
from heaven to earth, from earth to heaven,” in quell
of images and ideas fuited to the emotions he himfelf
feels, and to the fympathies he would communicate to
others. And, confequently, figures of fpeech, the ou-
fpring of excurfive fancy, muft (if he fpeak according
to what he is fuppofed to think and feel, that is, ac¬
cording to his fuppofed condition) tindure the lan¬
guage of the poet more than that of any other compo-
fier. So that, if figurative didlion be unnatural in geo¬
metry, becaufe all wanderings of fancy are unfuitable,
and even impoflible, to the geometrician, while intent
upon his argument; it is, upon the fame principle, per-
febtly natural, and even unavoidable, in poetry ; becaufe
the more a poet attends to his fubjebt, and the better
qualified he is to do it juftice, the more a Clive will Iffs
imagination be, and the more diverfified the ideas that
prefent themfelves to his mind.— Befides, the true
poet addreffes himfelf to the paftions and fympathies of
mankind ; which, till his own be raifed, he cannot hope
to do with fuccefs. And it is the nature of many paf-
fions, though not of all, to increafe the activity of ima¬
gination : andan-ablive imagination naturally vents it-
lelf in figurative language ; nay, unlefs reftrained by a
correbt tafte, has a tendency to exceed in it.; of which
Bifliop Taylor and Lord Verulam, two geniufes diffe¬
rent in kind, but of the higheft order, are memorable
examples.
We laid, that “ the poet feeks not to convince the
judgment of his reader by arguments of either real or
apparent cogency.” We do not mean, that in poe¬
try argument has no place. The moft legitimate rea-
foning, the foundeft philofophy, and narratives purely
hiftorical, may appear in a poem, and contiibute great¬
ly to the honour of the author, and to the importance
of his work. All this we have in Paradife Loft. We
mean, that what diftinguifties pure poetry from other
writing, is its altitude, not to fway the judgment by rea-
feningq
Part t.
POETRY
Of poetical foiling, 'but to plcafe tbe fancy, and move the paffions, by
Harmony. a lively imitation of nature. Nor would we exclude poe-
'—"'V ’ tical embellifliment from hitlory, or even from philofophy.
Plato’s Dialogues and the Moral Eflays of Addifon
and Johnfon aoound in poetic imagery ) and Livy and
Tacitus often amufe their readers with poetical defcrip-
tion. In like manner, though geometry and phyfics be
different fciences; though abftrabt ideas be the fubjeft,
and pure demonftration or intuition the evidence, of the
former •, and though the material univerfe, and the in¬
formations of feme, be the fubjedt and the evidence of
the latter ; yet have theft: fciences been united by the
beft philofophers, and very happy effetf:s refulted from
the union.——In one and the fame work, poetry, hitio-
ry, philofophy, and oratory, may doubtlefs be blended j
nav, thefe arts have all been actually blended in one and
the fame work, not by Milton only, but alfo by Ho¬
mer, Virgil, Lucan, and Shakefpeare. Yet ftill thefe
arts are different •, different in their ends and principles,
and in the faculties of the mind to which they are re-
fpe&ively addreffed : and it is eafy to perceive when a
writer employs one and when another.
§ 2. Of the Sound of Poetical Language.
As the ear, like every other perceptive faculty, is
capable of gratification, regard is to be had to the found
of words, even in profe. But to the harmony of lan¬
guage, it behoves the poet, more than any other writer,
to attend ; as it is more efpecially his concern to render
his work pleafurable. In fact, we find, that no poet was
ever popular who did not poffefs the art of harmonious
compofition.
What belongs to the fubjeft of Poetical Harmony
may be referred to one or other of thefe heads, Sweet-
nefs, Me afire, and Imitation.
I. In order to give fiveetnefs to language, either in
verfe or profe, all words of harfh found, difficult pro¬
nunciation, or unwieldy magnitude, are to be avowed as
much as poffible, unlefs when they have in the found
fomethmg peculiarly emphaticalj and words are to be
fo placed in refpeft of one another, as that difcordant
combinations may not refult from their union. But in
poetry this is more neceffary than in prefe ; poetical
language being underffood to be an imitation of natural
language improved to that perfection which is confiftent
with probability. To poetry, therefore, a greater lati¬
tude muff be allowed than to profe, in expreffing, by
tropes and figures of pleafing found, thofe ideas ■whereof
the proper names are in any refpebt offenfive, either to
the ear or to the fancy.
II. How far verfification or regular meafure may be
effential to this art, has been difputed by critical writers *,
fome holding it to be indilpenfably neceffary, and fome
not neceffary at all.
The faft feems to be, as already hinted, that to poe¬
try verfe is not effential. In a profe work, we may
have the fable, the arrangement, and a great deal of the
pathos and language, of poetry ; and fuch a wbrkis cer-
66
The poet
ought to
attend to
the har¬
mony of
language,
which con-
iifts iu
67
fiveetnefs
and
63 •
meafure,
which,
though not
eflential,
779
tainly a poem, though perhaps not a perfcCl one. For 0^^‘lncl
how abfurd would it be to fay, that by_ changing the " ar‘^jny',
pofition only of a word or two in each line, one might
divert Homer’s Iliad of the poetical charader ! At this
rate, the arts of poetry and verfification would be the
fame ; and the rules in Defpauter’s Grammar, and the
moral diffichs aicribed to Cato, would be as real poetry
as any part of Virgil. In fa&, fome very ancient poems,
when tranflated into a modern tongue, are far lefs poe¬
tical in veife than in profe ; the alterations neceffary to
adapt them to our numbers being detrimental to their
fublime fimplicity ; of which any perfon of tafte will be
fenfible, who compares our common profe-verfion ef
Job, the Pfalms, and the Song of Solomon, with the
beft: metrical paraphrafe of thole books that has yet ap¬
peared. Nay, in many cafes, Comedy will be more
poetical, becaufe more pleafing and natural, in profe
than in verfe. By verfifying Tom Jones, and Ibe
Merry Wives of Windfor, we ffiould fpoil the two finelt
comic poems, the one epic, the other dramatical, now in
the wrorld. _ i ^9
But, fecondly, though verfe be not effential to poetry, a(h‘st0
it is neceffary to the perfection of all poetry that admits eK”
of it. Verfe is to poetry, what colours are to paint- p0etry.
ing (G). A painter might uifplay great genius, and
draw mafterly figures with chalk or ink; but if he in¬
tend a perfect picture, he muff employ in his wwk as
many colours as are feen in the object he imitates. Or,
to adopt a beautiful comparifon oi Demofthenes, quoted
by Ariftotle *, “ Verfification is to poetry what bloom # jgheior.
is to the human countenance.” A good face is agree- lib. iii.
able when the bloom is gone, and good poetry may cap-4-
pleafe without verfification •, harmonious numbers may
fet off" an indifferent poem, and a fine bloom indifferent
features : but, without verfe, poetry is incomplete ; and
beauty is not perfect, unlefs to fweetnefs and regularity
of feature there be fuperadded
The bloom of young defire, and purple light of love.
If numbers be neceffary to the perfection of the higher
poetry, they are no lefs fo to that"of the lower kinds, to
Paftoral, Song, and Satire, which have little befides the
language and verfification to diftinguilh them from profe;
and which fome ancient authors are unwilling to admit to
the rank of poems : though it feems too nice a fcruple,
both becaufe fuch writings are commonly termed poeti¬
cal; and alfo becaufe there is, even in them, fomething
that may not improperly be confidered as an imitation of
nature.
That the rhythm and meafure of verfe are naturally
agreeable, and therefore that by thefe poetry may be
made more pleafing than it would be without them, is
evident from this, that children and illiterate people,
whofe admiration we cannot fuppofe to be the effeeff of
habit or prejudice, are exceedingly delighted with them.
In many proverbial fayings, where there is neither rhime
nor alliteration, rhythm is obvioufly ftudied. Nay, the
ufe of rhythm in poetry is univerfal; whereas alliteration
c F 2 and
(g) Horace feems to hint at the fame comparifon, when, after fpecifying the feveral forts of verfe fuitable to
Epic, Elegiac, Lyric, and Dramatic Poetry, he adds,
Defcriptas fervare vices, opcrumque colores.
Cur ego, fi nequeo ignoroque, Foeta falutor ? Ar. Poet. ver. 86.
780 P O £ T R Y;
Of Poetical and rliime, tliough reliilied by feme nations, are not much
, tiarmf->1)y fought after by others. And we need not be at a lofs
to account for the agreeablenefs of proportion and order,
if we refledt, that they fugged the agreeable ideas of
contrivance and Ikill, at the lame time that they render
the connedtion of things obvious to the underftanding,
and imprint it deeply on the memory. Verfe, by pro¬
moting dillindt and eafy remembrance, conveys ideas to
the mind with energy, and enlivens every emotion the
poet intends to raife in the reader or hearer. Befides,
when we attend to verfes, after hearing one or two, we
become acquainted with the meafure, which, therefore,
we always look for in the fequel. This perpetual inter¬
change of hope and gratification is a fource of delight j
and to this in part is owing the pleafure we take in the
rhimes of modern poetry. And hence we fee, that
though an incorredt rhime or untuneable verfe be in it-
felf, and compared with an important fentiment, a very
trilling matter j yet it is no trifle in regard to its effedls
on the hearer 5 becaufe it brings difappointment, and fo
gives a temporary {hock to the mind, and interrupts the
current of the affedtions; and becaufe it fuggefts the
difagreeable ideas of negligence or want of {kill on the
part of the author. And therefore, as the public ear
becomes more delicate, the negligence will be more gla¬
ring, and the difappointment more intenfely felt} and
Corredlnefs of rhime and of meafure will of courfe be
the more indifpenfible. In our tongue, rhime is more
necefl'ary to Lyric than to Heroic poetry. The reafon
feems to be, that in the latter the ear can of itfelf per-
In what ceive the boundary of the meafure, becaufe the lines are
cafes rhime an 0f equal length nearly, and every good reader makes
^rifecTwIth a ^ort Paufe at tf*6 end of each j whereas, in the for-
311 Englifh mer> ^nes vary in length : and therefore the rhime
poetry. is requifite to make the meafure and rhythm fufficiently
perceptible. Cuftom too may have feme influence. Eng-
lilh Odes without rhime are uncommon ; and therefore
have fomething aukward about them, or fomething at
lead; to which the public ear is not yet thoroughly re¬
conciled. Indeed, when the drama is excepted, we do
not think that rhime aan be fafely fpared from Englilh
poetry of any kind, but when the fubjeft is able to
fupport itfelf. “ He that thinks himfelf capable of
aftonifliing (fays Johnfon) may write blank verfe j but
thofe that hope only to pleafe, muft condefcend to
^lime.”
Rhime, however, is of lefs importance by far than
rhythm, which in poetry as wxdl as in mufic is the
fource of much pleafing variety j of variety tempered
with uniformity, and regulated by art; infomuch that,
notwithftanding the likenefs of one hexameter verfe to
another, it is not common, either in Virgil or Homer,
to meet with two contiguous hexameters whofe rhythm
is exactly the fame. And though all Englilh heroic
verfes confifi: of five feet, among which the iambic pre¬
dominates •, yet this meafure, in refpeft of rhythm alone,
is fufceptible of more than 30 varieties. And let it be
remarked further, that different kinds of verfe, by be¬
ing adapted to different fubjefts and modes of writing,
give variety to the poetic language, and multiply the
charms of this pleafing art.
What has formerly been fnown to be true in regard
to ftyle, will alfo in many cafes hold true of verfifica-
tion, “ that it is then natural when it is adapted to
the fuppofed condition of the fpeaker.”—-In the epopee
Pan I.
the poet affumes the' char after of calm infpiratfon and Of Poetical
therefore his language mult be elevated, and his num- Harmony,
bers majeftic and uniform. A peafant fpeaking in he-
roic or hexameter verfe is no improbability here j be- The lan-
caufe bis words are fuppofed to be tranfmitted by one guageofthe
who will of his own accord give them every ornament ePic Poet
neceffary to reduce them into dignified meafure *, as an muft,be eIe*
eloquent man, in a folemn affembly, recapitulating the hf,lumbers
fpeech of a clown, would naturally exprefs it in pure uniformly
and peripicuous language. The uniform heroic mea- majeftic.
lure will fuit any fubjeft of dignity, whether narrative
or didaftic, that admits or requires uniformity of llyle.
In tragedy, where the imitation of real life is more
perfeft than in epic poetry, the uniform magnifi¬
cence of epic numbers might be improper; becaule the
heroes and heroines are fuppofed to fpeak in their own
perfons, and according to the immediate impulfe of paf- 2
fion and fentiment. Yet, even in tragedy, the verfifica- In trlgedy
tion may be both harmonious and dignified; becaufe the the fame
eharafters are taken chiefly from high life, and theunifor.n?
events from a remote period j and becaufe the highermagniS‘
poetry is permitted to imitate nature, not as it is, but would be
in that ftate of perfeftion in which it might be. The improper,
Greeks and Romans confidered their hexameter as tooand muc.h
artificial for dramatic poetry ; and therefore in tragedy,more^0 m
and even in comedy, made ufe of the iambic, and fomeCGme y‘
other meafures that came near the cadence of converfa-
tion : we ufe the iambic both in the epic and dramatic
poem ; but for the molt part it is, or ought to be, much
more elaborate in the former than in the latter. In
dramatic comedy, where the manners and concerns of
familiar life are exhibited, verfe would feem to be unna¬
tural, except it be fo like the found of common difeourfe
as to be hardly diftinguilhable from it. Cuftom, how¬
ever, may in feme countries determine otherwife ; and
againft cuffom, in thefe matters, it is vain to argue.
The profeffed enthufiafm of the dithyrambic poet ren¬
ders wildnefs, variety, and a fonorous harmony of num¬
bers, peculiarly fuitable to his odes. The love-fonnet,
and Anacreontic fong, will be lefs various, more regu¬
lar, and of a fofter harmony ; becaufe the ftate of mind
expreffed in it has more compofure. Philofophy can
fcarce go further in this inveftigation, without deviating
into whim and hypothefis. The particular forts of
verfe to be adopted in the lower fpecies of poetry, are
determined by falhion chiefly, and the praftice of ap¬
proved authors.
III. The origin and principles of imitative harmony,
or of that artifice by which the found is made, as Pope
fays, “ an echo to the fenfe,” may be explained in the
following manner.
It is pleafing to obferve the uniformity of nature in A ftnking
all her operations. ' Between moral and material beauty analogy br¬
and harmony, between moral and material deformitytween mo~
and diffonance, there obtains a very ftriking analogy.ral a^ma'
The vifible and audible expreflions of almoft every vir- ty^id
tuous emotion are agreeable to the eye and the ear, and fonnity*.
thofe of almoft every criminal paffion difagreeable. The
looks, the attitudes, and the vocal founds, natural to
benevolence, to gratitude, to compaflion, to piety, are
in themfelves graceful and pleafing ; while anger, dif-
content, defpair, and cruelty, bring difeord to the voice,
deformity to the features, and diftortion to the limbs.
That flowing curve, winch painters know to be effen-
tial to the beauty of animal fliape, gives place to a mul¬
tiplicity
Part I.
P O E T R Y.
78 F
Of Poetical tiplicity of right lines and fliarp angles in the counte-
HaEmony. nance and gefture of him who knits his brows, ftvetches
his noftrils, grinds his teeth, and clenches his fift j
whereas, devotion, magnanimity, benevolence, content¬
ment, and good-humour, foften the attitude, and give a
more graceful fwell to the outline of every feature. Cer¬
tain vocal tones accompany certain mental emotions.
The voice of forrow is feeble and broken, that of de-
fpair boifterous and incoherent } joy aflfumes e fweet and
fprightly note, fear a weak and tremulous cadence •, the
tones of love and benevolence are mufical and uniform,
thofe of rage loud and diffonant ; the voice of the fedate
reafoner is equable and grave, but not unpleafant; and
he who declaims with energy, employs many varieties
of modulation fuited to the various emotions that predo¬
minate in his difcourfe.
But it is not in the language of paflion only that the
human voice varies its tone, or the human face its fea¬
tures. Every ftriking fentiment, and every interefting
idea, has an effett upon it. One would efteem that per-
fon no adept in narrative eloquence, who fhould defcrxbe,
with the very fame accent, fwift and flow motion, ex¬
treme labour and eafy performance, agreeable fenfation
and excruciating pain j who ftiould talk of the tumult
of a tempeftuous ocean, the roar of thunder, the de-
vaftations of an earthquake, or an Egyptian pyramid
tumbling into ruins, in the fame tone of voice where¬
with he defcribes the murmur of a rill, the warbling of
the harp of ./Eolus, the fwinging of a cradle, or the de-
fcent of an angel. Elevation of mind gives dignity to
the voice. From Achilles, Sarpedon, and Othello, we
fliould as naturally expeft a manly and fonorous accent,
' as a nervous ftyle and majeftic attitude. Coxcombs and
bullies, while they aflume airs of importance and valour,
affeft alfo a dignified articulation.
The fource Since ihe tones natural language are fo various,
ofimitative poetry, which imitates the language of nature, mull al-
harmony offo vary its tones; and, in refpeft of found as well as of
numbers, meaning, be framed after that model of ideal perfec¬
tion, which the variety and energy of the human arti¬
culate voice render probable. This is the more eafily
accomplifhed, becaufe m every language there is be- r:[arr'^(t)1ncal
tween the found and fenfe of certain words a perceptible , a™<lPy~ i
analogy ; which, though not fo accurate as to lead a
foreigner from the found to the fignification, is yet ac¬
curate enough to (how, that, in forming fuch words, re¬
gard has been had to the imitative qualities of vocal
found. Such, in Englifh, are the words yell, crajh,
crack, hifs, roar, murmur, and many others.
All the particular laws that regulate this fort of imi¬
tation, as far as they are founded in nature, and liable
to the cognizance of philofophy, depend on the general
law of ftyle above mentioned. Together with the other
circumftances of the fuppofed fpeaker, the poet takes
into confideration the tone of voice fuitable to the ideas
that occupy his mind, and thereto adapts the found of
his language, if it can be done confiftently with eafe and
elegance of expreflion. But when this imitative har¬
mony is too much fought after, or words appear to be
chofen for found rather than fenfe, the verfe becomes
finical and ridiculous. Such is Ronfard’s affedted imita¬
tion of the fong of the fky-lark:
Elle quindee du zephire
Sublime en 1’air vire et revire,
Et y declique un joli cris,
Qui rit, guerit, et tire I’ire
- Des efprit mieux que je n’ecris.
This is as ridiculous as that line of Ennius,
Turn tuba terribili fonitu taratantara dixit:
Or as the following verfes of Swift;
The man with the kettle-drum enters the gate,
Dub dub a dub dub : the trumpeters follow,
Tantara tantara ; while all the boys hollow.
Words by their found may imitate found; and quick What^har-
or flow7 articulation may imitate quick or flow motion, mosiy of
Hence, by a proper choice and arrangement of wTords,numbe.rs
the poet may imitate Sounds that are fweet with dig-canimi
nity (b),—fweet and tender (1),—loud (k),—and
harfh (l) ;—and. Motions that are flow, in confequence
of dignity (m),— flow in confequence of difficulty (n),
fwift
(h) No fooner had th’ Almighty ceas’d, than all
The multitude of angels, with a fhout
Loud as from numbers without number, fweet
As from bleft voices uttering joy ; heav’n rung
With jubilee, and loud hofannas fill’d
Th’ eternal regions.  Par. Lojl, iii.
See alfo thenight-ftorm of thunder, lightning, wand, and
rain, in Virg. Georg, lib. i. ver. 328—334.
fO Et longum, formofe, vale, vale, inquit, lola.
W Virg. Ecl.i.
Formofam refonare doces Amaryllida filvas.
Virg. Eel. i.
See alfo the fimile of the nightingale, Georg, lib. iv. verf.
511. And fee that wmnderful couplet deferibing the
wailings of the owd, .ZEneid iv. 462.
 —vibratus absethere fulgor
Cum fonitu venit, et mere omnia vifa repente,
Tyrrhenufque tuba? mugire per sethera clangor,
Sufpiciunt; iterum atque iterum fragor increpat
in gens, JEneid viii.
See alfo the ftorm in the firft book of the Aineid, and
in the fifth of the Odyffey.
(l) TheTioarfe rough verfe fhould like the torrent roar.
Pope.
 -On a fudden open fly,
With impetuous recoil and jarring found,
Th’ infernal doors, and on their hinges grate
Harfh thunder.—— Par. LoJ}, ii. 879.
See alfo Homer’s Iliad, lib. ii. ver. 363, and Clarke’s
Annotation.
(m) See an exquifite example in Gray’s Progrefs of
Poefy ; the conclufion of the third ftanza.
(n) And when up ten fteep flopes y.ra’ve dragg’d
your thighs. Pope.
Juft brought out this, when fcarce his tongue could
ftir. Pope,
• The huge leviathan
Wallowing unwieldy, enoimous in their gaft,
Tempeft the ocean. Par. LoJ}, vii, 412*
✓
7B2 POE
Of Poetical fxviFt and noiiy (©)—Fwift ai d fmoolli (p)—uneven
.Harmony., an(j abrupt (q_),—quick and joyous (r). An unex-
pefted paufe in the verfe may alfo imitate a hidden
failure of ftrength (s), or interruption of motion (t),
or give vivacity to an image or thought, by fixing our
attention longer than ufual upon the word that pre¬
cedes it (u).—Moreover, when tve defcribe great bulk,
it is natural for us to articulate flowly, even in common
difcourfe ; and therefore a line of poetry that requires
a flow pronunciation, or feems longer than it ftiould
be, may be ufed with good effeft in defcribing vaftnefs
of fize (x).—Srveet and fmooth numbers are moft pro¬
per, wdien the poet paints agreeable objedis, or gentle
energy (y) ; and hardier founds when he fpeaks of
what is ugly, violent, or difagreeable (z). This too
is according to the nature of common language j for
T it Y. Partr.
we generally employ hardier tones of voice to exprefs Of Poetical
what we diilike, and more melodious notes to defcribe Harmony,
the objefts of love, complacency, or admiration. Harfli
numbers, however, fliould not be frequent in poetry :
for in this art, as in mufic, concord and melody ought
always to predominate. And we find in faft, that good
poets can occafionally exprefs themfelves fomewhat hardi¬
ly, when the fubjedt requires it, and yet preferve the
fweetnefs and majefty of poetical dldtion. Further, the
voice of complaint, pity, love, and all the gentler affec¬
tions, is mild and mufical, and fliould therefore be imi¬
tated in mufical numbers j ivhile defpair, defiance, re¬
venge, and turbulent emotions in general, affume an
abrupt and fonorous cadence. Dignity of defcription
(a), folemn vows (b), and all fentiments that proceed
from a mind elevated with great ideas (c), require a
correfpon-
See the famous defcription of Sifyphus rolling the done,
OdylT. lib. xi. ver. 592. See Quintil. Inft. Orat.lib. ix.
cap. 4. § 4. compared ivith Paradife Loft, book ii. ver.
1022.
(o) Quadrupedante putrem fonitu quatit ungtila
campum. JEneid.
mreiTU, Tndovd& xvbiveiro Xccos uvutcitf . Odyjf. xi.
See alfo Virg. .ZEneid. lib. i. ver. 83—87.
(p) See wild as the winds o’er the defert lie flies.
Pvpe.
Ille volat, fimul arva fuga, fimul sequora verrens.
Virg.
TqtdiY) v iTrurec ttiXm, ftciXiTm tovirtt. Hejiod.
fQ_) UoXXx o’ cctxvTct xurxvrct ttx^xitx Tt 'So^tux t’
Horn.
The lafs fliriek’d, ftartecl up, and fhriek’d again,
Anonijm.
(r) Let the merry bells ring round,
And the jocund rebecks found,
To many a youth, and many a maid,
Dancing in the chequer’d fhade. Milt. Allegro.
See alfo Gray’s Progrefs of Poefy, ftanza 3.
(s) Ac velut in fomnis oculos ubi languida prefifit
Nofiie quies, nequicquam avidos extendere curfus
Velle videmur:—et in mediis conatibus segri
Succidimus.  JEneid.
See alfo Virg. Georg, lib. iii. ver. 515, 516.
(t) For this, be fure to-night thou ftialt have cramps,
Side-ftitches that (hall pen thy breath up. Urchins
Shall exercife upon thee.—-—
Profpero to Calyban in tJte Temfejl.
See Pope’s Iliad, xiii. 199.
(u) — How often from the fteep
Of eshoing hill or thicket have we heard
Celeftial voices, to the midnight air,
Sole,—or refponflve to each other’s note.
Singing their great Creator ?——Par. LoJ}.t iv.
And over them triumphant Death bis dart
Shook,——but delay’d t« ffrike. Id.
3
See alfo Horn. OdylT. lib. ix. ver. 290.
(x) Thus ftretch’d out, huge in length, the arch fiend
lay. Par. Lqft.
Monftrum horrendum, informe, ingens, cui lumen
ademptum. AEneid. iii.
Et magnos membrorum artus,magna ofifa,lacertofque
Exult, atque ingens media confiltit arena.
Jtineid. v. 422.
(y) Hie gelidi fontes, hie mollia prata, Lycori,
Hie nemus, hie ipfo tecum confumerer aevo.
Virg. Ed. x.
The dumb fhall fing ; the lame his crutch forego,
And leap, exulting, like the bounding roe.
Pope's McJJiah.
See Milton’s defeription of the evening, Par. Loft, book
iv. ver. 398—609.
Ye gentle gales beneath my body bloiv,
And foftly lay me on the ivaves below.
Pope's Sappho.
(z) Stridenti ftipula miferum difperdere carmen.
Virg. Eel. iii.
Immo ego Sardois videar tibi amarior herbis,
Horridior rufeo, projefla vilior alga.
Virg. Eel. vii.
Neu patriae validas in vifeera vertite vires.
Virg. JEneid. vi.
See alfo Milton’s defcription of the Lazar-houfe in Pa¬
radife Loft, book xi. ver. 477—492.
(a) See Virg. Georg. 1. 328. and Homer, Virgil,
and Milton, pqffim. See alfo Dryden’s Alexander’s
Feaft, and Gray’s Odes.
(b) See Virg. ^flEneid, iv. 24.
(c) Examples are frequent in the great authors. See
Othello’s exclamation:
   ■ - ■ ■ O now for e\rer
Farewell the tranquil mind ! &c. All m./c. 3»
Parti. POET II Y.
Of Poetical correfpondent pomp of language and vevMcation.—
Harmony. LaiUy, an irregular or uncommon movement in the
" v verfe may fometimes be of uie, to make tne reader con¬
ceive an image in a particular manner. Virgil, defcri-
bing horfes running over roeky heights at full fpeed,
begins the line with two dactyls, to imitate rapidity, and
concludes it with eight long iyilables:
Sax a per, et fcopulos, et deprefias convalles.
Georg, hi. 276.
which is very unufual meafure, but feems well adapted
to the thing expreffed, namely, to the deicent of the
783
animal from the hills to the low ground. At any rate, Of Poetical
this extraordinary change of the rhythm may be allow- Harmony. ^
ed to bear fome refemblance to the animal’s change of
motion, as it would be felt by a rider, and as we may
fuppofe it is felt by the animal itfelf.
Other forms of imitative harmony, and many other
examples, befides thole referred to in the margin, will
readily occur to all who are converfant in the writings
of the beft verfifiers, particularly Homer, Virgil, Mil¬
ton, Lucretius, Spenfer, Dryden, Shakefpeare, Pope,
and Gray.
Part II. Of the DIFFERENT SPECIES of POETRY, with their Particular Prik-
CIPLES.
Sect. I. Of Epic and Dramatic Compactions.
i I. T/iC Epopee and Drama compared.
Elem of TRAGEDY and the epic differ not in fubftantials
Criticifm. in both the fame ends are propelled, viz. inftru£hon and
76 amufement *, and in both the lame mean is employed,
In what vjz imitation of human actions. They differ only in
epic poeny the manner of imitating ; epic poetry employs narra-
agree, and tion 5 tragedy reprefents its fa&s as palling m our light:
in what in the former, the poet introduces himielr as an hifta-
they differ. r:;in . jn tjie latter, he prefents his a&ors, and never
himfelf.
This difference, regarding form only, may be thought
flight: but the effecls it occafions are by no means fo •,
for what we fee makes a deeper imprefiion than what
we learn from others. A narrative poem is a ftory told
by another : fadts and incidents palling upon the Rage,
come under our own obiervation } and are beude muen
enlivened by action and gelt are, expreflive of many fen-
timents beyond the reach of language.
A dramatic compofition has another property, in¬
dependent altogether of aftion } which is, that it makes
a deeper imprellion than narration : m the former, per-
ions exprefs their own lentiments ■, in the latter, ftna-
ments are related at fecond-hand. for tnat reaion, Ari-
t-hap Rotle, the father of critics, lays it down as a ruie ,
35. left. 6. That in an epic poem the author ought to have every
opportunity of introducing his adlors, and of confining
the narrative part within the narrowed bounds. Ho¬
mer underflood perfedlly the advantage of tuis method j
and his poems are both of them in a great meafure
dramatic. Lucan runs to the oppofite extreme : and
is guilty of a Hill greater fault, in fluffing his Pharfa-
/dj with cold and languid reflections, the merit of which
he affumes to himfelf, and deigns not to fhare with his
aClors. Nothing can be more injudicioufly timed, than
a chain of fueh reflexions, which fufpend the battle of
Pharfalia, after the leaders had made then Ipeeches, and
l Lib. vii. the two armies are ready to engage f. _
from line Ariilotle, from the nature of the table, divides tra-
385 to line gedy into fimple and complex : but it is of greater mo-
460, ment, with refpeX to dramatic as well as epic poetry,
T-Ji and to found a diftinXion upon the different ends attained
epk poetry by fuch compofitions. A poem, whether dramatic or
pathetic or epic, that has nothing in view but to move the paflkms
moral.
and to exhibit piXures of virtue and vice, may be di-
flinguilhed by the name of pathetic : but where a ftory
is purpofely contrived to iiluftrate fome moral truth, by
(bowing that diforderly paflions naturally lead to exter¬
nal misfortunes, fuch compofition may be denominated
moral. Befide making a deeper impreffion than can be
done by cool reafonmg, a moral poem does not fall Ihort
of reafoning in affording conviXion : the natural connec¬
tion of vice with mifery, and of virtue with happinefs,.
may be illuftrated by ftating a faX as well as by urging
an argument. Let us affume, for example, the follow¬
ing moral truths : Thai difeord among the chiefs renders
ineffe&ual all common meafures ; and that the conie-
querfees of a flightly-founded quarrel, foftered by pride
and arrogance, are not lefs fatal than thofe of the grof-
feit injury : thefe truths may be inculcated by the quar¬
rel between Agamemnon and Achilles at the fiege of
Troy. If faXs or circumilances be wanting, fuch as tend
to roufe the turbulent paffions, they mull be invented *,
but no accidental nor unaccountable event ought to be
admitted •, for the neceffary or probable connexion be¬
tween vice and mifery is not learned from any events
but what are naturally occafioned by the charaXers and
paffions of the perfons reprefented, aXing in fuch cir¬
cumilances. A real event, of which we fee not the
caufe, may afford a leffon, upon the prefumption that
what hath happened may again happen : but this cannot
be inferred from a ftory that is known to be a fiXion.
Many are the good effeXs of fuch compofitions. A ^
pathetic compofition, whether epic or dramatic, tends The goenf
to a habit of virtue, by exciting us to do what is right, effefts of
and reftraining us from what is wrong. Its frequent luc^c°^~
piXures of human woes produce, befide, two effeXs, *catRn *
extremely falutary : They improve our fympathy, and
fortify us to bear our misfortunes. A moral com¬
pofition muft obvioufly produce the fame good effeXs
becaufe by being moral it ceafeth not to be pathetic :
it enjoys befides an excellence peculiar to itfelf 5 for it
not only improves the heart, as above mentioned, but
inftruXs the head by the moral it contains. It feems
impoffible to imagine any entertainment more fuited
to a rational being, than a work thus happily iiluftra-
ting fome moral truth ; where a number of perfons o£
different charaXers are engaged in an important aXion,
fome retarding, others promoting, the great cataftrophe y
and where there is dignity of flyle as ivell as of mat¬
ter. A work of tills kind has. our fympathy at com-
maadj.
784
POETRY.
Of the
Epopee and
Drama.
_ 79
The fame
fubjedts not
always fit
for tragic
and epic
poetry.
* Blair's
Lf:ci arcs.
80
The proper
i'ubjedt of
an epic
•poem.
^ John/on't
Life of
Milton.
mand, and can put in motion the whole train of the
focial affections : our cunoiity in fome fcenes is ex¬
cited, in others gratified j and our delight is confum-
mated at the dole, upon finding, from the characters
and fituations exhibited at the commencement, that
every incident down to the final cataftrophe is natural,
and that the whole in conjunction make a regular chain
of caufes and effeCts.
Confidering that an epic and a dramatic poem are the
fame in fubftance, and have the fame aim or end, one
will readily imagine, that fubje&s proper for the one
muff be equally proper for the other. But confidering
their difference as to form, there will be found reafon
to correCt that conjeCture, at leaft in fome degree.
Many fubjeCts may indeed be treated with equal ad¬
vantage in either form : but the fubjeCts are ftill more
numerous for which they are not equally qualified ; and
there are fubjeCts proper for the one and not at all for
the other. To give fome flight notion of the difference,
as there is no room here for enlarging upon every arti¬
cle, we obferve, that dialogue is better qualified for ex-
preffing fentiments, and narrative for difplaying faCts.
Heroifm, magnanimity, undaunted courage, and other
elevated virtues, figure belt in aCtion : tender paflions,
and the whole tribe of fympathetic afteCtions, figure belt
in fentiment. It clearly follows, that tender paffions are
more peculiarly the province of tragedy, grand and he¬
roic aCtions of epic poetry.
“ The epic poem is univerfally allowed to be *, of all
poetical works, the moft dignified, and, at the fame time,
the moft difficult in execution. To contrive a ftory which
ftiall pleafe and intereft all readers, by being at once en¬
tertaining, important, and inftruCtive j to fill it wdth fuit-
able incidents ; to enliven it with a variety of characters
and of deferiptions •, and, throughout a long work, to
maintain that propriety of fentiment, and that elevation
of ftyle, which the epic character requires, is unqueftion-
ably the higheft effort of poetical genius.
“ The aCtion or fubjeCt of the epic poem muft be great
and interefting. Without greatnefs it would not have fuf-
ficient importance either to fix our attention or to juftify
the magnificent apparatus which the poet beftows on it.
This is fo evidently requifite as not to require illuftration $
and, indeed, hardly any who have attempted epic poetry
have failed in choofing fome fubjeCt fufficiently important,
either by the nature of the aCtion or by the fame of the
perfonages concerned in it. The fame of Homer’s heroes,
and the confequences of diffenfion between the greateft
of them, is a fubjeCt important in itfelf, and muft have
appeared particularly fo to his countrymen, who boafted
their defeent from thofe heroes. The fubjeCt of the iEneid
is ftill greater than that of the Iliad, as it is the founda¬
tion of the moft powerful empire that ever was eftablifh-
ed upon this globe j an event of much greater import¬
ance than the deftruCtion of a city, or the anger of a fe~
mibarbarous warrior. But the poems of Homer and Vir¬
gil fall in this refpeCt infinitely ftiort of that of Milton.
‘ Before the greatnefs difplayed in Paradife Loft, it has
been wTell obferved § that all other greatnefs {brinks away.
The fubjeft of the Englilh poet is not the deftruCtion of
a city, the conduCt of a colony, or the foundation of an
empire : it is the fate of wmrlds, the revolutions of hea¬
ven and earth 5 rebellion againft the Supreme King, raif-
ed by the higheft order of created beings; the overthrow
iff their hoft, and the puniftimeut oi their crime j the crea-
4
Part II.
tion of a new race of reafonable creatures; their original Of the
happinefs and innocence, their forfeiture of immortality, EP°Ijee an^
and their reftoration to hope and peace.” , *)ranfia- ^
An epic poem, however, is defective if its aClion be
not interefting as well as great; for a narrative of mere
valour may be lb conftruCted as to prove cold and tire-
fome. “ Much * will depend on the happy choice of* jifa,-rubi
fome fubjeCt, which {hall by its nature intereft the pu-fupra.
blic j as when the poet feleCts for his hero one who is
the founder, or the deliverer, or the favourite of his na¬
tion ; or when he writes atchievements that have been
highly celebrated, or have been connected with import¬
ant confequences to any public caufe. Moft of the great
epic poems are abundantly fortunate in this refpeCt, and
muft have been very interefting to thofe ages in which
they were compofed.” The fubjeCt of the Paradife Loft,
as it is infinitely greater, muft likewife be coniidered as
more univerfally interefting than that of any other poem.
“ We all feel the effeCts of Adam’s tranfgreftion j we all
fin like him, and like him muft all bewail our offences.
We have reftlefs and infidious enemies in the fallen angels,
and in the bleffed fpirits we have guardians and friends
in the redemption of mankind we hope to be included j
in the defeription of heaven and hell "we are furely inte-
refted, as we are all to refide hereafter either in the regions
of horror or blifs.” $ t
“ The chief circumftance which renders an epic poem Circum-
interefting f, and which tends to intereft not one age or^ances.
country alone, but all readers, is the Ikilful conduCt of^reftin^in
the author in the management of his fubjeCh His plan epic poetry,
muft comprehend many affefting incidents. He may f Blair and
fometimes be awful and auguft ; he muft often be tender
and pathetic j he muft give us gentle and pleafing fcenes
of love, friendftiip, and] affeCtion. The more that an
epic poem abounds with fituations which awaken the feel¬
ings of humanity, it is the more interefting. In this
refpeCl perhaps no epic poets have been fo happy as Vir¬
gil and Taffo. The plan of the Paradife Loft comprifes
neither human aftions nor human manners. The man
and woman who aCt and fuffer, are in a ftate which no
other man or woman can ever know7. The reader finds
no tranfaClion in which he can be engaged ; beholds no
condition in which he can by any effort of imagination
place himfelf 5 he has therefore little natural curiofity or
fympathy.’’ u
A queftion has been moved, Whether the nature ofWhether
the epic poem does not require that the hero ftiould bethe 1’iero
ultimately fuccefsful ? To this queftion Johnfon replies,™^ r^e{“
that “ there is no reafon why the hero ftiould not be i'uccefbful.
unfortunate, except eftablifhed praClice, fince fuccefs and
virtue do not neceffarily go together.” Moft critics,
however, are of a different opinion, and hold fuccefs to
be, if not the neceffary, at leaft the moft proper iffue of
an epic poem. An unhappy conclufion depreffes the
mind, and is oppofite to the elevating emotions which
belong to this fpecies of poetry. Terror and compaffiom
are the proper fubje&s of tragedy *, but as the epic is of
larger extent, it w7ere too much, if, after the difficulties
and troubles which commonly abound in the progrefs of
the poem, the author Ihould bring them all at laft to an
unfortunate conclufion. We know7 not that any author
of name has held this courfe except Lucan ; for in the
Paradife Loft, as Adam’s deceiver is at laft crufhed, and
he himfelf reftored to the favour of his maker, Milton’s
hero muft be coniidered as finally fuccefsful.
We
Part II. POE
Of the We have net ecc&fion to fay more of the epic, con-
Epqpee and peered as peculiarly adapted to certain fubj^dls, and to
. -Dl^ma jjg condudled according to a certain plan. JBut as dra¬
matic fubjeds are more complex, it is neceffary to take
a narrower view of them. They are either tiie light
and the gay, or the grave and aftedhng, incidents of
human life. The former conilitute the lubjed of co¬
medy, and the latter of tragedy.
As great and ferious objects command more attention
than little and ludicrous ones j as the fall ot a hero in-
terefts the public more than the marriage of a private
perfon ; tragedy has been always held a more dignified
entertainment than comedy. The firlt thing required of
the tragic poet is, that he pitch upon feme moving and
intereihng ilory, and that he conduct it. m a natural and
probable manner. For we muft obferve, that the natu¬
ral and probable are more effenlial to tragic than even to
epic poetry. Admiration is excited by the wonderful j
but paffion can be railed only by the imprelfions of na-
ture and truth upon the mind.
Subjects The fubjeft bed fitted for tragedy is where a man has
beft fuited hJmfelf been the caule of his misfortune j not fo as to be
to tragedy, guilty, nor altogether innocent: the misfortune
mult be occadoned by a fault incident to human nature,
and therefore in fome degree venial. Such misfortunes
call forth the focial affections, and warmly interelt the
ipeftator. An accidental misfortune, if not extremely
lingular, doth not greatly move our pity: the perfoa who
fullers, being innocent, is freed from the greated of all
torments, that anguilh of mind which is occafioned-by
remorfe. An atrocious criminal, on the other hand, who
brings misfortunes upon himfelf, exenes little pity, for a
different reafon : his remorfe, it is true, aggravates his
didrefs, and fwells the firft emotions of pity : but then
our hatred of him as a criminal blending with pity, blunts
its edge conliderably. Misfortunes that are not innocent,
nor highly criminal, partake the advantages of each ex¬
treme they are attended w.’ith remorfe to embitter the
diftrefs, which raifes our pity to a great height; and the
flight indignation we have at a venial fault detra&s not
fenlibly from our pity. I he happieft of all fubjedts ac¬
cordingly for railing pity, is where _ a man of integrity
falls into a great misfortune by doing an a£Hon that is
innocent, but which, by fome fingular means, is con¬
ceived by him to be criminal : his remorfe aggravates
his didrefs ; and our compaflion, unredrained by indig¬
nation, knows no bounds. Pity comes thus to be the
ruling palfion of a pathetic tragedy and, by proper re-
prefentation, may be raifed to a height fcarcely exceed¬
ed by any thing felt in real life. A moral tragedy takes
in a larger field ; as it not only exercifes our pity, but
raifes another palfion, which, though felfifh, deferves to
be cherilhed equally with the focial alfiecfion. The paf¬
fion we have in view is fear or terror ; for when a raif-
fortune is the natural confequence of fome wrong bias
in the temper, every fpeftator who is confcious of fuch a
bias in himfelf takes the alarm, and dreads his falling
into the fame misfortune : and by the emotion of fear or
terror, frequently reiterated in a variety of moral trage¬
dies, the fpe&ators are put upon their guard againlt the
diforders of naffion.
The commentators upon Ariftotle, and other critics,
have been much gravelled about the account given of
tragedy by that author : “ That by means of pity and
terror, it refines or purifies in us all forts of padion.” But
Vol. XVI. Part II,
T It Y. 7*5
no one who has a clear conception of the end and effects ^ Of the
of a good tragedy, can have any difficulty about Ariilotle’s ^
meaning : Our pity is engaged for the perfons reprefent- ^ ~ .
ed ; and our terror is upon our own account. Pity indeed
is here made to Hand for all the fyinpathetic emotions, be-<
caufe of thefe it is the capital. There can be no doubt,
that our fympathetic emotions are refined er improved
by daily exercife; and in what manner our otiter pat-
fions are refined by terror, has been juit now laid. One
thing is certain, that no other meaning can juilly be
given to the foregoing dotlrine than that now men¬
tioned ; and that it was really Ariftotle’s meaning,
appears from his 13th chapter, where he delivers feve-
ral propofitions conformable* to the doctrine as here ex¬
plained. Thefe, at the fame time, we take liberty to
mention ; becaule, fo far as authority can go, they con¬
firm the foregoing reafoning about fubjecls proper for
tragedy. The firlt propofition is, That it being the pro¬
vince of tragedy to excite pity and terror, an innocent per¬
fon falling into adverfity ought never to be the fubjeft.
This propofition is a neceffary confequence of his doftrine
as explained ; a fubjeft of that nature may indeed excite
pity and terror ; but the former in an inferior degree, and
the latter in no degree for moral inilruction. The fecond
propofftion is, That the hiitory of a wicked perfon in a
change from miifery to happinefs ought not to be repre-
fented ; which excites neither terror nor compaffion, nor
is agreeable in any refpect. The third is, That the mis¬
fortunes of a wicked perfon ought not to be reprefsnted :
fuch reprefentation may be agreeable in fome meafure upon
a principle of juftice; but it will not move our pity, or
any degree of terror, except in thole of the fame vicious
difpofitiou with the perfon reprefented. The laid propo-
fition is, That the only character fit for reprefentation lies
in the middle, neither eminently good nor eminently bad;
where the misfortune is not the effect ol deliouate vice,
but of fome involuntary fault, as our author expreires it.
The only objection We find to Ariftotle’s account of tra¬
gedy, is, that he confines it within too narrow bounds, by
refufing admittance to the pathetic kind : for if le.-ror bs
efiential to tragedy, no reprefentation deferves that name
but the moral kind, where the misfortunes exhibited are
caufed by a wrong balance of mind, or feme diforder in
the internal conftitution : fuch misfortunes always fugged:
moral inftruction ; and by fuch misfortunes only can ter¬
ror be excited for our improvement.
Thus Ariftotle’s four propofitions above-mentioned,
relate folely to tragedies of the moral kind. Thofe oi:
the pathetic kind are not confined within fo narrow li¬
mits : fubjefts fitted for the theatre are not in fuch
plenty as to make us reje£t innocent misfortunes which
roufe our fyrapathy, though they inculcate no moral.
With refpeeft indeed to the fubjecls of that kind, it
may be doubted, whether the conclufion ought not al¬
ways to be fortunate. Where a perfon of integrity is
reprefented as fuffering to the end under misfortunes
purely accidental, we depart difeontented, and with feme
obfeure fenfe of injuftice : for feldoin is man fo fubmif*
five to Providence, as not to revolt againft the tyranny
and vexations of blind chance; he will be tempted tb
fay, this ought not to be. We give for an example the
Romeo and Juliet of Shakefpeare, where the fatal cata-
ftrophe is occalioned by Friar Lawrence’s coming to the
monument a minute too late ; we are vexed at the un¬
lucky chance, and go away diifatisfied. Such iropref-
5 G fions,
785
POE
Of the fions,’ vvliich ought not to be ehenfhed, are a fufficient
Epopee and reafon for excluding itories of this kind from the
Drama.
S5
theatre.
The misfortunes
of a virtuous perfon, arifing from
The impro- ncceSfary caufes, or a chain of unavoidable circumilances,
per ufe of as they excite a notion of deftiny, are equaily unfatisfac-
de ft my in tory to the human mind. A metaphysician in his do-
trao-edieo1 fet may reafon himfelf into the belief of fate, or what in
modern language is called phiiofophica! neceflity ; but the
feelings of the heart revolt again!! that doftrine ; and
we have the confeffion of the two ableft philofophers by
whom it was ever maintained, that men conduft them-
felves through life as if their will were absolutely free,
and their actions no part of a chain of neceffary caufes
and effects. As no man goes to the theatre to ftudy
metaphyfics, or to diveft himfelf of the common feelings
of humanity, it is impofnhle, whatever be his philoi'o-
phical creed, that he fliould contemplate without horror
and difguft an innocent perfon fuffering by mere deltiny.
A tragedy of uncommon merit in every other refpect
may indeed be endured, nay perhaps admired, though
Inch be its cataltrophe *, becaule no work of man was
ever perfedt ; and becaule, where imperfections are un¬
avoidable, a multitude of excellencies may be allowed to
cover one fault : but we believe the mifery of an inno¬
cent perfon refulting from a chain of unavoidable cir-
cumitances has never been confidered as a beauty by
minds unperverted by a falfe philofophy. “ It muff be
acknowledged * that the fubjedts of the ancient Greek
tragedies were frequently founded on mere deftiny and
inevitable misfortunes. In the courfe of the drama ma¬
ny moral fentiments occurred ; but the only inftrudtion
which the fable conveyed was, that reverence was due
to the p-cds, and fubmifiion to the decrees of fate. Mo-
* Blair.
86
How it is
ufed in the
tragedy of
the Rob¬
bers.
dern tragedy has aimed at a higher object, by becoming
mor? the theatre-of paflion •, pointing out to men the
confequences of their own mifcondudt, fhowing the dire¬
ful effedts which ambition, jealoufy, love, refentment,
Jmd other fuch ffrong emotions, when mifguided or left
unreftrained, produce upon human life. An Othellp,
hurried by iealoufy to murder bis innocent wife ; a Jaf-
fier enfnared by refentment and want to engage in a
confpiracy, and then Hung with remorfe and involved
in ruin ; a Siffredi, through the deceit which he employs
for public-fpirited ends, bringing deftrudtion on all
whom he loved : thefe, and fuch as thefe, arc the ex¬
amples which Tragedy now difplays to public view ; and
by means of which it inculcates on men the proper go¬
vernment of their paflions.”
There is indeed one Angular drama, in which deftiny
is employed in a manner very different from that in
which it was ufed by the poets of Greece and Rome.
It is Schiller’s tragedy of the Robbers, of which “ the
hero endowed by nature (as the tranflator of the piece
obferves) with the moft generous feelings, animated by
the higheft fenfe of honour, and fufceptible of the warm-
eft affections of the heart, is driven by the perfidy of a
brother, and the fuppofed inhumanity of his father, into
a ftate of confirmed mifanthropy and defpair.” He with¬
es that he “ could blow the trumpet of rebellion through
all nature; that he could extinguifh with one mortal
Ifiow the viperous race of men j and that he could fo
{trike as to deftroy the germ of exiftence.” In this fi-
tuation he is hurried on to the perpetration of a feries of
crimes which find from their very magnitude and atro-
T R Y. Tart II.
city a recommendation to his difterapeved mind; Sen- Of the
fible all the while of his own guilt, and fuffering for that
guilt the fevereft pangs of remorfe, he yet believes him-, ' ’ ,
ielf an inftrument of vengeance in the hands ot the Al¬
mighty for the puniftiment of the crimes ot others. In
thus accompliihing the dreadful deftiny which is pre-
feribed for him, he teels a tpecies of gloomy fatisfaCtion,
at the fame time that he confiders himlelt as doomed to
the performance of that part in life which is to contign
his memory to infamy and his foul to perdition. After
burning a town, he exclaims, “ O God of vengeance !
am I to blame for this ? Art thou to blame, O Father
of Heaven ! when the inftruments of thy wrath, the pef-
tilence, flood, and famine overwhelm at once the righ¬
teous and the guilty ? Who can command the flames to
flay their courfe, to deftroy only the noxious vermin,
and fpare the fertile field ?” yet with the fame breath he
acufes himfelf of extreme criminality for “ prefumptuouf-
ly wielding tire fword of the Molt High 1” He frequent¬
ly laments in the molt affeCting manner the lofs of his
innocence, withes that “ he could return into the womb
that bare him, that he hung an infant at the breafl,
that he were born a beggar, the meaneft hind, a pea-
fant of the field.” He confiders himfelf as the outcait
of Heaven, and finally rejected by the Father of mercy j
yet he tells the band of robbers whom he commanded,
that the “ Almighty honoured them as agents in his
hands to execute his wonderous purpofes; employed
them as his angels to execute his ftern decrees, and pour
the vials of his wrath j” and in a very folemn prayer,
he fuppofes that “ the God who ruleth over all had de¬
creed that he fliould become the chief of thefe foul mur¬
derers.”
“ It will be allowed, (fays the tranfiator), that the ima¬
gination could not have conceived a ipectacle more
deeply interefting, more powerfully aftedting to the
mind of man, than that of a human being thus charac-
terifed and acting under fuch impreflions. Ihe compaf-
fionate intereft which the mind feels in the emotions or
fufferings of the guilty perfon, is not diminithed by the
obfervation, that he acls under an imprefiion of inevi¬
table deftiny •, on the contrary, there is fomething in our
nature which leads us the more to compaflionate the hr-
ftrument of thofe crimes, that we fee him confider him¬
felf as bound to guilt by fetters, which he has the con-
ftant with, but not the ftrength, to break.”
This is indeed true : we fympathife with the hero of
the Robbers, not only on-account of his exalted fenti¬
ments and his inflexible regard to the abftradt principles
of honour and juftice, but much more for that diforder
of intelledt which makes him fuppofe “ his deltiny fixed
and unalterable,” at the very time that he is torn with
remorfe for the perpetration of thofe crimes by which he
believed it to be fulfilling. Deftiny, however, is not in
this tragedy exhibited as real, but merely as the phan¬
tom of a diftempered though noble mind. Had the poet
reprefented his hero as \n faci decreed by God, or bound
by fate, to head a band of foul murderers, and to com¬
mit a feries of the moft atrocious crimes •, though our pi¬
ty for him might not have been leffened, the impreffions
of the whole piece on the mind could have been only
thofe of horror and difguft at what would have appeared
to us the unequal ways of providence.
The Tragedy of the Robbers is a ftriking inftance of
the juftnefs of Dr Blair’s criticifm, in oppofition to that
of
Part U. POE
Of the of Lord Samos'. His lordfhip holds that it is eflential
Epopee and a gOOCi tragedy, that its principal fa&s be borrowed
. ;from hiftory 5 becaufe a mixture of known truth with
87 the fable tends to delude us into a conviction of the re-
Whether ality of the whole. The Doctor confiders this as a mat-
the fubje d ter of no great confequence ; for “ it is proved by expe-
flvmhf h we r‘ence> ttlat a fi^itious tale, if properly conduced, will
Ik founda- meh the heart as much as any real hiitory j” this obfer-
tion in vation is verified in the Robbers. It is indeed a very ir-
truth. regular drania, and perhaps could not be aCted on a
Britiih theatre. But although the whole is known to be
a fiCtion, we believe there are few effufions of human ge¬
nius which more powerfully excite the emotions of ter¬
ror and pity. Truth is indeed congenial to the mind }
and when a fubjeCl proper for tragedy occurs in hiftory
or tradition, it is perhaps better to adopt it than to in¬
vent one which has no fuch foundation. But in choof-
ing a fubjeCt which makes a figure in hiftory, greater
precaution is rieceflary than where the whole is a fiCtion.
In the latter cafe, the author is under no reftraint other
than that the characters and incidents be juft copies of
nature. But where the ftory is founded on truth, no
circumftances muft be added, but fuch as conneCt natu¬
rally with what are known to be true; hiftory may be
fupplied, but muft not be contradicted. Further, the
fubjeCt chofen muft be diftant in time, or at leaft in
place for the familiarity of recent perfons and events
ought to be avoided. Familiarity ought more efpecially
to be avoided in an epic poem, the peculiar character of
which is dignity and elevation : modern manners make
but a poor figure in fuch a poem. Their familiarity un¬
qualifies them for a lofty fubjeCt. The dignity of them
will be better underftood in future ages, when they are
no longer familiar.
After Voltaire, no writer, it is probable, will think of
rearing an epic poem upon a recent event in the hiftory
of his own country. But an event of that kind is per¬
haps not altogether unqualified for tragedy : it was ad¬
mitted in Greece; and Shakefpeare has employed it fuc-
cefsfully in feveral of his pieces. One advantage it pof-
fefles above fiClion, that of more readily engaging our
belief, which tends above any other particular to raife
our fympathy. The feene of comedy is generally laid
at home : familiarity is no objection j and we are pecu-
88 liarly fenfible of the ridicule of our own manners.
How atra- After a proper fubjeCl is chofen, the dividing it into
gedy fliould pavts requires fome art. The conclufion of a book in an
into acts'- CP*C Poem> or an a<^ a P^ay» cannot be altogether
and how’ arbitrary -, nor be intended for fo flight a purpofe as to
many a&s make the parts of equal length. The fuppofed paufe at
it fhou’d the end of every book, and the real paufe at the end of
have. every aft, ought always to coincide with fome paufe in
E/em. of the aCtion. In this refpeCt, a dramatic or epic poem
jnticijm, OUght to referable a fentence or period in language, di¬
vided into members that are diftinguifhed from each
other by proper paufes ; or it ought to referable a piece
of mufic, having a full clofe at the end, preceded by im-
T R Y. 787
perfeCt clofes that contribute to the melody. The divi- Of the
lion of every play into Jive aCts has no other foundation EP°Pee ancf
than common praCtice, and the authority of Horace (d). ; jl‘*1T>a' .
It is a divifion purely arbitrary j there is nothing in the
nature of the compofition which fixes this number rather
than any other 5 and it had been much better if no fuch
number had been afeertained. But, fince it is afeertain-
ed, every aCt in a dramatic poem ought to clofe with
fome incident that makes a paufe in the aCtion ; for
otherwdfe there can be no pretext for interrupting the re-
prefentation. It would be abfurd to break off in the
very heat of aCtion •, againft which every one would ex¬
claim : the abfurdity ftill remains where the aCtion re¬
lents, if it be not actually fufpended for fome time. This
rule is alfo applicable to an epic poem : though in it a
deviation from the rule is lets remarkable ; becaufe it is
in the reader’s power to hide the abfurdity, by proceed¬
ing inftantly to another book. The firlt book of Para-
dife Loft ends without any clofe, perfeCt or imperfeCt :
it breaks off abruptly, where Satan, feated on his throne,
is prepared to harangue the convocated holt of the fall¬
en angels *, and the fecond book begins with the fpeech.
Milton feems to have copied the Aineid, of which the
turn firft books are divided much in the fame ’manner.
Neither is there any proper paufe at the end of the
feventh book of Paradife Loft, nor at the end of the
eleventh. In the Iliad little attention is given to this
rule.
Befides tragedy, dramatic poetry comprehends co-T. 8^.
medy and farce. Thefe are fufficiently diftinguifhed of comedy.
from tragedy by their general fpirit and ftrain. “ While
pity and terror, and the other ftrong paffions, form the
province of the tragic mufe, the chief or rather foie in-
ftrument of comedy and farce is ridicule.” Thefe two
fpecies of compofition are fo perpetually running into
each other, that we (hall not treat of them feparately1 j
fince what is now known by the name of farce differs in
nothing effential from what was called the old comedy
among the Greeks. “ Comedy propofes for its objeCt * * Blair'i
neither the great fufferings nor the great crimes of men; Lettuces,
but their follies and flighter vices, thofe parts of their
charaCler which raife in beholders a fenfe of impropriety,
which expofe them to be cenfured and laughed at by
others, or which render them trouble fome in civil fo-
ciety.
“ The fubjeCts of tragedy are not limited to any age
or country; but the feene and fubjeCl of comedy fhould
always be laid in our own country, and in our own times.
The reafon is obvious : thofe decorums of behaviour,
thofe leffer diferiminations of character, which afford fub¬
jeCl for comedy, change with the differences of countries
and times $ and can never be fo well underftood by fo¬
reigners as by natives. The comic poet, who aims at
correCling improprieties and follies of behaviour, fhould
‘ catch the manners living as they rife.’ It is not his
bufinefs to amufe us with a tale of other times 5 but to
give us pictures taken from among ourfelves; toTatirize
5 G 2 reigning
(d) Neve minor, neu Jit quinto produBior aBu
Fabula. De Arte Poetica.
If you would have your play deferve fuccefs,
Give it five aCts complete, nor more nor lefs. Francis.
7 S'8
f O E T R Y. Part n,
the fentiraents and tone of lungaagc Ought to be fubfer- Cf the
vient to thefe, fo as to appear natural and proper for Epopee,
the occafion. *
Ot the reigning and prefent vices j to exhibit to the age a faith-
coP^ with its humours, its follies, and its
\ , extravagancies.
•90 “ Comedy maybe divided into two kinds: comedy , . ......
Comedy of of charafiti\ and comedy of intrigue. The former is the $ 2‘ peculiarities of hie Epopee and Drama.
t wo-kinds. - - - ~ 6
, 91
The com-
twion faults
'of comedy.
'* Kurd.
The ftyle
-of comedy.
more valuable fpeexes 5 becaufe it is the bufmefs of co¬
medy to exhibit the prevailing manners which mark the
-chat adder of the age in which the fccne is laid: yet there
fnould be always as much intrigue as to give us fome-
thing to with and fome:hing to fear, 't he incidents
mould fo fucceed one another, as to produce linking
fituations, and to fix our attention 5 while they afford at
the fame time a proper field for the exhibition of charac¬
ter. The action in comedy, though it demands the
poet’s care in order to render it animated and natural,
is a lefs figmficant and important part of the performance
than the action in tragedy: as in comedy it is what men
fay, and how they behave, that draws our attention, ra¬
ther than what they perform or what they firfer.
“ In the management of characters, one of the mofl
common faults of comic writers is the carrying of them
too far beyond life. Wherever ridicule is concerned, it
is indeed extremely difficult to hit the precife point
where true wit ends and buffoonery begins. When the
mifer in Plautus, fearebing the perfon whom he fufpects
of having fcolen his cafket, after examining firff his right
'hand and then his left, cries out, of ende etiam tertiam —
’ ihow me your, third hand,’ there is no one but muff be
fcufible of the extravagance. Certain degrees of exag¬
geration are allowed to the comedian, but there are li¬
mits fet to it by nature and good talle 5 and fippofing
the inifer to be ever fo much engrofied by his jealoufy
and his fulpicions, it is impofiible to conceive any man
in his wits fufpeCting another of having more than two
hands.”
It appears from the plays of Ariifophanes which re¬
main, that the characters in the old comedy of Athens
were almolt always overcharged. They were likewife
direCt and avowed fatires againft particular perfons, who
were brought upon the ftage by name. “ The ridicule
employed in them is extravagant, the wit for the mod
part buffo or. i tli and farcical, the raillery biting and cruel,
and the obfeenity that reigns in them is grofs and intole¬
rable. They feem to have been compoled merely for the
mob.” Yet of thefe abominable dramas, an excellent
critic* has affirmed, with too much truth, that what is
now called force is nothing more than the lliadow. The
characters in genuine comedy are not thofe of particular
and known perfons, but the general characters of the
age and nation; which it requires no fmall (kill to diftin-
guifli clearly and naturally from each other. In attempt¬
ing this, poets are too apt to contrail characters and in¬
troduce them always in pairs; which gives an affeded air
to the whole piece. The perfection of art is to conceal
art. “ A mafterly writer will give us his characters
diltinguifhed rather by fuch fhades of diverfity as are
commonly found in fociety, than marked witli fuch
ftrong oppofiiions as are rarely brought into actual con-
trad in any of the circumdances of real life.”
The dyle of comedy ought to be pure, elegant,
and lively, very feldom rifing higher than the ordinary
tone of polite converfation ; and upon no occafion de-
feending into vulgar, mean, and grofs expredions; and
in one word, aCtion and character being the funda¬
mental parts of every epic and dramatic compodtioUj
epic.
In a theatrical entertainment, which employs both v-a„p;!,ier
the eye and the ear, it would be a grofs abfurdity toTnVavc Y
in troduce upon the flage fuperior beings in a vifibie diape.no place in
There is no place for fuch objection in an epic poem;a fh-ama,
and Boileau, with many other critics, declares ftrong-1101
ly for that fort of machinery in an epic poem. But wa¬
ving authority, which is apt to impofe upon the judge¬
ment, let us draw what light we can from re a f on. We
may in the ftrd place oblerve, that this matter is but
indidinCtly handled by critics : the poetical privilege of
animating infenfible objects for enlivening a defeription,
is very different from what is termed machinery, where
deities, angels, devils, or other fupernatural powers, are
introduced as real perfonages, mixing in the aCtion, and
contributing to the catadrophe 5 and yet thefe two
things are condantly jumbled together in reafoning.
I he former is founded on a natural principle: but
nothing is more unnatural than the latter. Its effects,
at the fame time, are deplorable. Bird, it gives an air
of fiction to the whole } and prevents that impreflion of
reality which is requifite to intereil our affections, and
to move our pardons; which of itfelf is fudicient to ex¬
plode machinery, whatever entertainment it may afford
to readers of a iantaftic tade or i’-regular imagination. 94
And, next, were it poffible, by difguifing the fiction, to has it a
delude us into a notion of reality, an infuperabie objec-
tion would dill remain, which is, that the aim or end of n tne
an epic poem can never be attained in any perfeClion
where machinery is introduced *, for an evident re a ton,
that virtuous emotions cannot be raifed fuccefsfully but
by the actions of thofe who arc endued with paifiions
and affections like our own, that is, by human aCtions j
and as for moral indruCtion, it is clear, that none can
be drawn from beings who aCt not upon the fame
principles with us. A fable in Af,fop’s manner is no ob¬
jection to this reafoning : his lions, bulls, and gcats,
are truly men under difguife ; they aCt and feel in every
refpeCt as human beings 5 and the moral we draw is
founded on that fuppofition. Homer, it is true, intro¬
duces the gods into his fable : but the religion of his
country authorized that liberty ; it being an article in
the Grecian creed, that the gods often interpole vifibly
and bodily in human affairs. It mud however be ob-
ferved, that Homer’s deities do no honour to his poems:
fictions that trangrefs the bounds of nature, feldom
have a good effeCt; they may inflame the imagination
for a moment, but will not be relifhed by any perfon of
a correCt tade. They may be of fome ufe to the lowrer
rank of writers 5 but an author of genius has much finer
materials, of Nature’s production, for elevating his fub-
jeCt, and making it intereding.
One wrould be apt to think, that Boileau, declaring
for the Heathen deities, intended them only for embel-
lidiing the diCtion : but unluckily he banifhes angels and
devils, who undoubtedly make a figure in poetic lan¬
guage, equal to the Heathen deities. Boileau, there¬
fore, by pleading for the latter in oppofition to the form¬
er, certainly meant, if he had any didinCt meaning, that
the Heathen deities may be introduced as aCtors. And,
in fad, he himfelf is guilty of that glaring abfurdity,
where.
Part II.
POE
Oi the where ft is not fo pardonable as in an epic poem : In his
Epop.-e. ocje Upon the taking of Namur, he demands with a molt
fcrious countenance, whether the walls were built by
Apollo or Neptune : and in relating the paffage of the
Rhine, anno 1672, he defcribes the god of that river as
fighting with all his might to op pole the French mo¬
narch ; which is confounding fiction with reality at a
ft range rate. The French writers in general run into
this error : wonderful the effect of cultom, entirely to
hide from them how ridiculous fuch fidtions are.
That this is a capital error in Giernfalevime Lilcra-
ta, Taflo’s greatett admirers muft acknowledge : a hi na¬
tion can never be intricate, nor the reader even in pain
about the cataftrophe, fo long as there is an angel, devil,
or magician, to lend a helping hand. Voltaire, in his
effav upon epic poetry, talking of toe Pnarfaha, ob-
ferves judicioully, “ That the proximity of time, the no¬
toriety of events, tire character oc the age, enlightened
and political, joined with the folidityof Lucan’s fubject,
deprived him of poetical fidtion.” Is it not amazing,
that a critic who reafons fo juffly with rcfpedt to others,
can be fo blind with refpect to- himlelf ? Voltaire, not
fatisfied to enrich his language with images drawn from
invillble and fuperior beings, introduces them into the
action : in the fixth canto of the Hsnnade, St Louis
appears in perfon, and terrifies the foldiers j in the fe-
venth canto, St Louis fends the god of Sleep to Henry j
and, in the tenth, the Demons of Difcord, Fanaticifm,
War, See. affift Aumale in a {ingle combat with Turenne,
and are driven away by a good angel brandifhing the
fword of God. To blend fuch hdtitious perfonages
in the fame adtion with mortals, makes a bad figure
at any rate j and is intolerable in a hiftory lo recent
as that of Henry IV. But perfeclion is not the lot of
man.
But perhaps the mod fuccefsful vreapon that can be
employed upon this fubjedl is ridicule. Addifon has
applied this in an elegant manner : “ \\ hereas the time
of a general peace is, in all appearance, drawing near ;
being informed that there are leveral ingenious perfovs
who intend to (how their talents on io happy an occa-
fion, and being willing, as much as in me lies, to pre¬
vent that effufion of nonfenfe ivhich we have good caufe
to apprehend ; I do hereby ftridtly require every perfon
who {hall write on this fubjedt, to remember that he is
a Chriftian, and not to Tacrifice his catechiim to his
poetry. In order to it, I do expedl of him, in the firft
place, to make his own poem, without depending upon
Phoebus for any part of it, or calling out for aid upon
any of the Miifes by name. I do likewife pofilively
forbid the fending of Mercury with any particular mef-
f.ge or difpatch relating to the peace j and {hall by no
means fuffer Minerva to take upon her the {nape of any
plenipotentiary concerned in this great work. 1 do fur¬
ther declare, that I (hall not allow the Deftinies to have
had a hand in the deaths of the feveral thoufands who
have been {lain in the late war 5 being of opinion that
all fuch deaths may be well accounted for by the Chvi-
ilian fyftem of powder and ball. I do therefore ftridlly
forbid the Fates to cut the thread of man’s life upon any
pretence whatfoever, unlefs it be for the lake of rhyme.
And whereas I have good reafon to fear, that Neptune
will have a great deal of bufinefs on his hands in feveral
pcems which we may now fuppofe are upon the anvil,
I do alfo prohibit his appearance, unlefs it be done in
f R Y,
789
metaphor, fimile, of any very fhort afluffcn y and that Of the
even here he may not be permitted to enter, but with , EP°Pee-' t
great caution and circumlpedlion. 1 defire that the
fame rule may be extended to his whole fraternity of
Heathen gods; it iting my defign to condemn every
poem to the dames in which Jupiter thunders, or exer-
cifes any other aft of authority which does not belong
to him. In ihort, I expeft that no pagan agent {hall
be introduced, or any faft related which a man cannot
give credit to with a good confcience. Provided al¬
ways, that nothing herein contained {hall extend, or be
con it rued to extend to feveral of the female poets in
this nation, who {hall dill be left in full poffeflion of
their gods and goddeifes, in the fame manner as if this
paper had never been written.” Spe5t. N° 523.
The marvellous is indeed fo much promoted by ma¬
chinery, that it is not wonderful to find it embraced by
the bulk of writers, and perhaps of readers. If in¬
dulged at all, it is generally indulged to excefs. Ho¬
mer introduceth his deities with no greater ceremony
than his mortals; and Virgil has dill lefs moderation :
a pilot fpent with watching cannot fall afleep and drop
into the lea by natural means : one bed cannot receive
the two lovers PCneas and Dido, without the immediate
interpolltion of fuperior powers. The ridiculous in fuch
fiftions mull appear even through the thickeft veil oi
gravity and folemnity.
Angels and devils ferve equally with Heathen deities
as materials for figurative language j perhaps better
amoug Chridians, becaufe we believe in them, and not
in Heathen deities. But every ojie is fenfible, as well
as Boileau, that the invidble powers in our creed make
a much vvorfe figure as aftors in a modern poem than the
invifible powers in the Heathen creed did in ancient
poems •, the caufe of which is not far to feek. The
Heathen deities, in the opinion of their votaries, were
beings elevated one dep only above mankind, lubjeft to
the fame padions, and diredled by the fame motives j
therefore not altogether improper to mix with men in
an important aftion. In our creed, fuperior beings are
placed at filch a mighty diltance from us, and are of a
nature lb different, that with no propriety can we appear
with them upon the fame dage : man, a creature much
inferior, lofes all dignity in the comparifon.
There can be no doubt that an hidorical poem admits An hiltori-
fhe embellidiment of allegory as well as of metaphor,cal Poem
fimile, or other figure. Moral truth, in particular, is |||
finely iliudrated in the allegorical manner 1 it amufes the &:C. under
fancy to find abllraft terms, by a fort of magic, meta- proper re¬
in or phofed into aftive beings •, and it is delightful to ftriftion*.
trace a general propofition in a piftured event. But
allegorical beings diould be confined within their own
fphere, and never be admitted to mix in the principal
aftion, nor to co-operate in retarding or advancing the
catadrophe j which would have a dill worfe effeft than
invifible powers : for the impredion of real exidence,
effential to an epic poem, is inconfident with that figu¬
rative exidence which is effential to an allegory ; and
therefore no method can more effeftually prevent the
impredion of reality than the introduftion of allegorical
beings co-operating with thofe whom we conceive to
be really exifting. The love-epifode in the Henriade
(canto 9.), infufferable by the difeordant mixture of al¬
legory with real life, is copied from that of Rin-aldo and
Artnida in the Gierujalemme Liber a la ^ which hath no
merit
POE
Of the merit to entitle it to be copied. An allegorical objecl,
hpopee. fuc'n as Fame in the Aineid, and the Temple of Love iu
tlie Plenviade, may find place in a defcription : but to in¬
troduce Difcord as a real perfonage, imploring the af-
fiftance of Love as another real pfrfonage, to enervate
96
Epifode de-
fintd.
97
What con-
ftttutes a
good epi¬
fode.
the courage of the hero, is making thefe figurative beings
aft beyond their fphere, and creating a Itrange jumble
of truth and fiftion. The allegory of Sin and Death
in the Paradife Loft is poflibly not generally relifhed.
though it is not entirely of the fame nature with what
we have been condemning , in a work comprehending
the atchievements of fuperior beings there is more ro®m
for fancy than where it is confined to human aftions.
What is the true notion of an epifode ? or how is it
to be diftinguiftied from the principal aiflion i* Every
incident that promotes or retards the cataftrophe muft
be part of the principal atftion. This clears the nature
of an epifode } which may be defined, “ An incident
connefled with the principal atftion, but contributing
neither to advance nor retard it.” The defcent of
JEneas into hell does not advance or retard the cata-
ftrophe, and therefore is an epifode. The ftory of Nifus
and Euryalus, producing an alteration in the affairs of
the contending parties, is a part of the principal aftion.
The family-fcene in the fixth book of tire Iliad is of the
fame nature ; for by Heftor’s retiring from the field of
battle to vifit his wife, the Grecians had opportunity
to breathe, and even to turn upon the Trojans. The
unavoidable eft'efl of an epifode according to this defi¬
nition muft be, to break the unity of aftion j and there¬
fore it ought never to be indulged unlefs to unbend the
mind after the fatigue of a long narration. An epifode,
when fuch is its purpofe, requires the following condi¬
tions : it ought to be well connefled with the principal
a£Hon } it ought to be lively and interefting j it ought
to be ftiort} and a time ought to be chofen when the
principal aftion relents (e).
In the following beautiful epifode, which clofes the
fecond book of Fingal, all thefe conditions are united.
u Comal was a fon of Albion 5 the chief of an hun¬
dred hills. His deer drunk of a thoufand ftreams; and
a thoufand rocks replied to the voice of his dogs. His
face was the mildnefs of youth ; but his hand the death
of heroes. One was his love, and fair was fire ! the
daughter of mighty Conloch. She appeared like a fun-
beam among women, and her hair was like the wing of
the raven. Her foul was fixed on Comal, and ftie was
his companion in the chace. Often met their eyes of
love, and happy were their words in fecret. But Gor-
mal loved the maid, the chief of gloomy Ardven. He
watched her lone fteps on the heath, the foe of unhappy
Comal.
“ One day, tired of the chace, when the mift had
concealed their friends, Comal and the daughter of
Conloch met in the cave of Ronan. It was the wonted
haunt of Comal. Its fides were hung with his arms *, a
hundred ftiields of thongs were there, a hundred helms
of founding fteel. Reft here, laid he, my love Galvina,
i
R Y.
Part II.
thou light of the cave of Ronan: a deer appears on Of the
Mora’s brow j I go, but, foon will return. 1 tear, faid e-
the, dark Gormal my fee : I will reft here} but foon
return, my love.
“ He went to the deer of Mora. The daughter of
Conloch, to try his love, clothed her white fide with
his armour, and ftrode from the cave of Ronan. Think¬
ing her his foe, his heart beat high, and his colour
changed. He drew the bow : the. arrow flew : Galvina
fell in blood. He ran to the cave with hufty fteps, and
called the daughter of Conloch. Vv here art thou, my
love ? but no anfwer.- He marked, at length, her
heaving heart beating again ft the mortal arrow. O
Conloch’s daughter, is it thou i—he funk upon her
breaft.
“ The hunters found the haplefs pair. Many and
filent were his fteps round the dark dwellings of his
love. The Heet of tha ocean came : he fought, and tire
ftrangers fell : he fearched for death over the field ; but
who could kill the mighty Comal ? Throwing away his
ftiield, an arrow' found his manly breaft. He lleeps with
his Galvina: their green tombs are feen by the mariner
when he bounds on the waves of the north.”
9s
Next, upon the peculiarities of a dramatic poem. And Double plot
the firft we (hall mention is a double plot : one of which ^aniit
muft refemble an epifode in an epic poem ; for it would i-l(cceis£ul>
diftraft the fpe&ator, inftead of entertaining him, if he
were forced to attend at the fame time to two capital
plots equally interefting. And even fuppofing it an
under-plot like an epifode, it feldom hath a good efteft
in tragedy, of which fimplicity is a chief property} for
an interefting fubjeft that engages our affedfions, occu¬
pies our whole attention, and leaves no room for any fe-
parate concern. Variety is more tolerable in comedy }
which pretends only to amufe, without totally occupy¬
ing the mind. But even there, to make a double plot
agreeable, is no flight effort of art: the under plot
ought not to vary greatly in its tone from the principal}
for difeordant emotions are unpleafant when jumbled
together} which, by the way, is an infuperahle ob-
jebfion to tragi-comedy. Upon that account the Pro¬
vok’d Hu {band deferves cenfure} all the feenes that
bring the family of the Wrongheads into adlion, being
ludicrous and farcical, are in a very different tone from
the principal feenes, difplaying fevere pnd bitter expo-
ftulations between Lord Townley and his lady. The
fame objedfion touches not the double plot of the Care-
lefs Hufband } the different fubjedfs being fweetly con-
nedfed, and having only fo much variety as to refemble
(hades of colours harmonioufly mixed. But this is not
all. The tinder plot ought to be connected with that
which is principal, fo much at leaft as to employ the
fame perfons : the under-plot ought to occupy the inter¬
vals or paufes of the principal adtion } and both ought
to be concluded together. This is the cafe of the
Merry Wives of Windfor. 99
Violent adtion ought never to be reprefented on the T '°^ent /IC*
ftage. While the dialogue goes on, a thoufand parti-
culars reprefent¬
ed.
(e) Homer’s defcription of the fhield of Achilles is properly introduced at a time when the adtion relents, and
the reader can bear an interruption. But the author of Telemachus deicribes the ftiield of that young hero in
the heat of battle ; a very improper time for an interruption.
a
Part IT.
POE
Of the culars concur to delude us into an impreilion of reality $
, Diitma. , genuine fentiments, paflionate language, and perfuafive
gefture : the fpeftator, once engaged, is walling to be
deceived, lofes fight of himfelt, and without 1'cruple
enjoys the fpedtacle as a reality. From this abfent
ftate he is roufed by violent adlion j lie wakes as from
a pleafing dream •, and, gathering his fenfes about him,
finds all to be a fiction. Horace delivers the fame rule j
and founds it upon the fame reafon:
Ne pueros coram populo Medea trucidet 5
Aut humana palam coquat exta nefarius Atreus j
Aut in avem Progne vertatur, Cadmus in anguem :
Quodcumque oftendis mihi lie, incredulus odi.'
The French critics join with Horace in excluding blood
from the ftage 5 but overlooking the moft fubftantial
objedtion, they urge only that it is barbarous and {hock¬
ing to a polite audience. The Greeks had no notion
of fuch delicacy, or rather effeminacy j witnefs the mur¬
der of Clytemneftra by her fon Oreftes, palling behind
the feene, as reprefented by Sophocles: her voice is
heard calling out for mercy, bitter expoftulations on his
part, loud ihrieks upon her being {tabbed, and then a
deep filence. An appeal may be made to every perfon
of feeling, whether this feehe be not more horrible than
if the deed had been committed in fight of the fpe6ta-
tots upon a Hidden guff of pafiion. If Corneille, in re-
prefenting the affair between Horatius and his lifter,
upon which the murder enfues behind the feene, had no
other view but to remove from the fpeftators a fhocking
action, he was guilty of a capital miftake : for murder
in cold blood, which in fome meafure was the cafe as
reprefented, is more (hocking to a polite audience, even
where the conclufive ftab is not feen, than the fame a£t
performed in their prefence by violent and unpremedita¬
ted paffion, as fuddenly repented of as committed. Ad-
*St>e£lator, difon’s obfervation is juft*, That no part of this inci-
44* dent ought to have been reprefented, but referved for
a narrative, with every alleviating circumftance in fa-
100 vour of the hero.
The proper . A few words upon the dialogue, which ought to be
thelha* ^ con^U(^e^ as to be a true reprefentation of nature.
logue.1" We talk not here of the fentiments nor of the language
(which are treated elfewhere) 5 but of what properly be¬
longs to dialogue-writing ; where every fingle fpeech,
Ihort or long, ought to arife from what is faid by the
former fpeaker, and furnifh matter for what comes after
till the end of the feene. In this view, all the fpeeches
from firft to laft reprefent fo many links of one regular
chain. No author, ancient or modern, poffeffes the art
of dialogue equal to Shakefpeare. Dryden,-in that par¬
ticular, may juftly be placed as his oppofite. He fre¬
quently introduces three or four perfons fpeaking upon
the fame fubje£t, each throwing out his own notions
feparately, without regarding what is faid by the reft :
take for an example the firft feene of Aurenzebe. Some¬
times he makes a number club in relating an event, not
to a ftranger, fuppofed ignorant of it, but to one another,
for the fake merely of fpeaking ; of which notable fort
of dialogue we have a fpecimen in the firft feene of the
firft part of the Conqueft of Granada. In the fecond
part of the fame tragedy, feene fecond, the King, Aben-
ariiar, and Zulema, make their feparate obfervations,
like fo many foliloquies, upon the fluftuating temper of
the mob j a dialogue fo uncouth puts one in mind of two
TRY.
fhepherds in a paftoral excited by a prize to pronounce
verfes alternately, each in praife of his own miftrefs.
This manner of dialogue-writing, befides an unnatural
air,,has another bad effedt; it ftays the courfe of the ac¬
tion, becaufe it is not productive of any confequcnce.
In Congreve’s comedies, the a£tion is often fufpended to
make way for a play of wit.
No fault is more common among writers than to pro¬
long a fpeech after the impatience of the perfon to wThom
it is addrefied ought to prompt him or her to break in.
Confider only how the impatient ador is to behave in,
the mean time. To exprefs his impatience in violent
a&ion without interrupting would be unnatural; and yet
to diflemble his impatience, by appearing cool w'here he
ought to be highly inflamed, would be no lefs fo.
lihyme being unnatural and difguftful in dialogue, is
happily banifhed from our theatre : the only wonder is
that it ever found admittance, efpecially among a people
accuftomed to the more manly freedom of Shakefpeare’s
dialogue. By banilhing rhyme, w'e have gained fomuch
as never once to dream that there can be any further
improvement. And yet, however fuitable blank verfe
may be to elevated charaders and warm paflions, it muft
appear improper and affeded in the mouths of the kuver
fort. Why then fhould it be a rule, That every feene.
in tragedy muft be in blank verfe ? Shakefpeare, with,
great judgement, has followed a different rule ; which is,
to intermix profe with verfe, and only to employ the lat¬
ter where it is required by the importance or dignity of
the fubjed. Familiar thoughts and ordinary fads ought
to be expreffed in plain language : to hear, for example,
a footman deliver a Ample meffage in blank verfe * muft
appear ridiculous to every one who is not biaffed by,
cuftom. In fhort, that variety of charaders and of
fituations, which is the life of a play, requires not
only a fuitable variety in the fentiments, but alfo in
the didion.
3. The Three Unities.
When we confider the chain of caufes and effeds in
the material world, independent of purpofe, defign, or
thought, we find a number of incidents in fucceflion,
without beginning, middle, or end : every thing that
happens is both a caufe and an effed j being the effed
of what goes before, and the caufe of what follows : one
incident may afted us more, another lefs j but all of
them are links in the univerfal chain : the mind, in
viewing thefe incidents, cannot reft or fettle ultimately
upon any one j but is carried along in the train without
any clofe. _ . . ■ rer
But when the intelledual w*orld is taken under view, In what the
in conjundion with the material, the feene is varied, unity of
Man ads with deliberation, will, and choice : he aims^10115-011”
at fome end j glory, for example, or riches, or ednqueft,
the procuring happinefs to individuals, or to his country
in general: he propofes means, and lays plans to attain
the end propofed. Here are a number of fads or inci¬
dents leading to the end in view, the whole compofing
one chain by the relation of caufe and effed. In running
over a feries of fuch fads' or incidents, we cannot reft
upon any one \ becaufe they are prefented to us as
means only, leading to fome end ; but we reft with fa-
tisfadion upon the end or ultimate event $ becaufe there
the purpofe or aim of the chief perfon or perfons is ac-
complifhed. This indicates the beginning, the middle,
and ,,
792 POE
r'‘ eThree and the end, of what Aiiilotle calls an entire acii^n *.
TJnlJkj- The flory naturally begins with deferibing thofe circum-
* c. 6. ^ances move perfon who afts the principal
part to form a plan, in order to compafs fome defired
event j the profecution of that plan, and the obftnnfHons,
carry the reader into the heat of adlion ; the middle is
properly where the adtion is the mod involved ; and the
end is where the event is brought about, and the plan
accomplifhed.
We have given the foregoing example of a plan
crowned with fuccefs, becaufe it affords the cleared con¬
ception of a beginning, a middle, and an end, in which
confids unity ot aftion ; and indeed dridler unity can¬
not be imagined than in that cafe. Hut an adlion may
have unity, or a beginning, middle, and end, without
fo intimate a relation of parts ; as where the cataldrophe
is different from what is intended or defired, which
frequently happens in our bed tragedies. In the iEneid,
Ftem of t^e a'Ler may obdruftions, makes his plan ef-
Criticnm. '"'’he Iliad is formed upon a different model:
it begins with the quarrel between Achilles and Aga¬
memnon ; goes on to deferibe the feveral effects produ¬
ced by that caufe ; and ends in a reconciliation. Here
is unity of aclion, no doubt, a beginning, a middle, and
an end ; but inferior to that of the iEneid, which will
thus appear. The mind hath a propenfity to go for¬
ward iti the chain of hidory 5 it keeps always in view
the expefted event; and when the incidents or under-
parts are connefted by their relation to the event, the
mind runs fweetly and eafily along them. This plea¬
sure we have in the /Eneid. It is not altogether fo
pleafant to conned!, as in the Iliad, effects by their
common caufe ; for fuch connection forces the mind to
a continual retrofpecl) looking backward is like walk-
roz ing backward.
Unity of . If unity of adlion be a capital beauty in fable imita-
aCtion a tive of human affairs, a plurality of unconnected fables
beauty. mu*\ a caP'la^ deformity. For tire lake of variety
we indulge an under-plot that is connected wdth the
principal; but trvo unconnected events are extremely
unpleafant, evCn where the fame aCtors are engaged in
both. Ariodo is quite licentious in that particular : he
carries on at the fame time a plurality of unconnected
dories. His only excufe is, that his plan is perfectly
well adjuded to his fubjeCt j for every thing in the 0r~
lando Funofo is wild and extravagant.
Though to date faCts in the order of time be natural,
yet that order may be varied for the fake cf confpicuous
beauties. . If, for example, a noted dory, cold and
fimple in its fird movements, be made the fubjeCt of an
epic poem, the reader may be hurried into the heat of
aChon \ referving the preliminaries for a converfation
piece, if thought neceffary j and that method, at the
fame time, has a peculiar beauty from being dramatic.
But a privilege that deviates from nature ought to be
fparingly indulgedand yet romance writers make no
difficulty of prefenting to the reader, without the lead
preparation, unknown perfons engaged in fome arduous
adventure equally unknown. In Caffandra, two per-
fonages, who afterwards are difeovered to be the heroes
cf the fable, dart up completely armed upon the banks
of the Euphrates/ and engage in a Angle combat.
A play analyfed is a chain of connected faCts, of wffiich
each feene makes a link. Each feene, accordingly, ought
to produce fome incident relative to the cataftrophe or ui
3
T R Y.
Part II,
timate event, by advancing or retarding it. A feene that The Three
produceth no incident, and for that reafon may be termed Unities.
barren, ought not to be indulged, becaufe it breaks the " v '
unity of action : a barren feene can never be intitlcd to a
place, becaufe the chain is complete-without it. In the
Old Bachelor, the 3d feene of a£t 2. and all that follow
to the end of that aCt, are mere converfation-pieces, pro-
dudtive of no confequence. The 10 th and nth feenes,
a£t 3. Double Dealer, and the 10th, nth, 12th, 13th,
and 14th feenes, adt I. Love for Love, are of the lame
kind. Neither is The Way of World entirely guiltlef*
of fuch feenes. It will be no juftification that they help
to difplay charadters : it were better, like Dryden in his
dramatis p erf once, to deferibe charadters beforehand, which
would not break the chain of adtion. But a writer of genius
has no occafion for fuch artifice ; he can difplay the cha¬
radters of his perfonages much more to the life in fenti-
ment and adtion. How fuccefsfully is this done by Shake-
fpeare ! in whofe works there is not to be found a Angle
barren feene.
Upon the whole, it appears, that all the fadts in an hi-
fforical fable ought to have a mutual connedtion, by their,
common relation to the grand event or catallrephe. And
this relation, in which the unitp of adtion confiits, is equal¬
ly effential to epic and dramatic compofitions.
How far the unities of time and of place are effential, ,, I93
is a queition of greater intricacy. Thefe unities were ^
itridtly obferved in the Greek and Roman theatres 5 and tim/and
they are inculcated by the French and Englilh critics asf>f place be
effential to every dramatic compofiticn. In theory thefe efl'ent!al*
unities are alfo acknowledged by our belt poets, though
their pradtice leldom correfponds: they are often forced
to take liberties, which they pretend not to juftify, againfl
the pradtice of the Greeks and Romans, and againlt the
folemn deciAon of their own countrymen. But in the
courfe of this inquiry it will he made evident, that in this
article we are under no neceflity to copy the ancients ;
and that our critics are guilty of a miftake, in admitting
no greater latitude of place and time than was admitted
in Greece and Rome.
Indeed the unities of place and time are not, by the
molt rigid critics, required in a narrative poem. In fuch
compoAtion, if it pretend to copy nature, thefe unities
would be abfurd ; becaufe real events are feldom confin¬
ed within narrow limits either of place or of time 1 and
yet we can follow hiftory, or an hiitorical fable, through
all its changes, with the greatel! facility ; we never once
think of meafuring the real time by what is taken in read¬
ing •, nor of forming any connedtion between the place of
adtion and that which we occupy.
We are aware, that the drama differs fo far from the
epic as to admit different rules. It will be obferved,
“ That an hiitorical fable, intended for reading folely,
is under no limitation of time or of place more than a
genuine hiflory ; but that a dramatic compofition cannot
be accurately reprefented unlefs it be limited, as its re-
prefer.tation is, to one place and to a few hours ; and
therefore that no fable can be admitted but what has thefc
properties, becaufe it would be abfurd to compofe a piece
for reprefentation that cannot be juftly reprelented.”
This argument has at leaf! a plaufible appearance j and
yet one is apt to fufpedt fome fallacy, confidering that
no critic, however Itridt, has ventured to confine the uni¬
ties of place and of time within fo narrow bounds.
A view of the Grecfon drama, compared with our owa,
may
Part II.
104
They were
elfential to
the Greek
drama, but
*0S
not to the
French or
Englifli.
POE
may perhaps relieve us from-this dilemma : if they be dif¬
ferently conitru&ed, as lhall be made evident, it is poffible
that the foregoing reafoning may not be equally applicable
to both.
All authors agree, that tragedy in Greece was derived
from the hymns in praife of Bacchus, which were fung in
parts by a chorus. Thefpis, to relieve the fingers, and
for the fake of variety, introduced one aftor, whole pro¬
vince it was to explain hiftorically the fubjedt of the long,
and who occalionally reprefented one or other perfonage.
Efchylus, introducing afecond actor, formed the dialogue j
by which the performance became dramatic 5 and the ac¬
tors were multiplied when the fubjedt reprefented made it
neceffary. But Itill the chorus, which gave a beginning
to tragedy, was conlidered as an effential part. The hrit
fcene, generally, unfolds the preliminary circumltances
that lead to the grand event; and this fcene is by Ari-
ftotlc termed the prologue. In the fecond fcene, where
tfie adtion properly begins, the chorus is introduced, which,
as originally, continues upon the ftage during the whole
performance : the chorus frequently makes one in the dia¬
logue j and wrhen the dialogue happens to be fufpended,
the chorus, during the interval, is employed in fmging.
Sophocles adheres to this plan religiouily. Euripides is
not altogether fo corredt. In fome of his pieces it be¬
comes neceffary to remove the chorus for a little time :
but when that unufual itep is rilked, matters are fo or¬
dered as not to interrupt the reprefentation : the chorus
never leave the ftage of their own accord, but at the
command of fome principal perfonage, who conftantly
waits their return.
Thus the Grecian drama is a continued reprefentation
without any interruption \ a circumftance that merits
attention. A continued reprefentalion without a paufe
affords not opportunity to vary the place of adlion, nor
to prolong the time of the action beyond that of the re¬
prefentation. To a reprefentation fo confined in place
and time, the foregoing reafoning is ftridtly applicable :
a real or feigned adtion, that is brought to a conclufion
after confiderable intervals of time and frequent changes
of place, cannot accurately be copied in a reprefenta¬
tion that admits no latitude in either. Hence it is, that
the unities of place and of time, wrere, or ought to have
been, ftridtly obferved in the Greek tragedies j which is
made neceffary by the very conftitution of their drama,
for it is abfurd to compofe a tragedy that cannot be juftly
reprefented.
Modern critics, who for our drama pretend to eftablifh
rules founded on the pradtice of the Greeks, are guilty
of an egregious blunder. The unities of place and of
time were in Greece, as we fee, a matter of neceftity,
Hot of choice •, and it is eafy to fhow, that if v/e fubmit
to fuch fetters, it muft be from choice, not neceffity.
This will be evident upon taking a view of the conftitu¬
tion of our drama, which differs widely from that of
Greece} whether more or lefs perfedl, is a different
point, to be handled afterward. By dropping the chorus,
opportunity is afforded to divide the reprefentation by in¬
tervals of time, during which the ftage is evacuated and
the fpedlacle fufpended. This qualifies our drama for fub-
jedts fpread through a wide fpace both of time and of place:
the time fuppofed to pafs during the fufpenfion of the re¬
prefentation is not meafured by the time of the fufpenfion;
and any place may be fuppofed, as it is not in fight: by
Vol. XVL Part XI.
T RY. 793
which means, many fubjecls can be juftly reprefented in The three
our theatres, that were excluded from thofe of ancient Unities.
Greece. This dodlrine may be illuftrated, by comparing 1
a modern play to a let of hiltorical pidtures; let us fup-
pole them five in number, and the refemblance will be
complete : each of the pidtures refembles an adt in one
of our plays : there muft neceffarily be the ftridteft unity
of place and of time in each pidture 5 and the fame ne-
ceflxiy requires thefe two unities during each adt of a
play, becaufe during an adt there is no interruption in
the fpedtacle. Now, when we view in fucceffion a num¬
ber of fuch hiftorical pidtures, let it be, for example, the
hiftory of Alexander by Le Brun, we have no difficulty
to conceive, that months or years have paffed between
the events exhibited in two different pidtures, though the
interruption is imperceptible in paffing our eye from the
one to the other j and we have as little difficulty to con¬
ceive a change of place, however great : in which view,
there is truly no difference between five adts of a modern
play and five fuch pidtures. Where the reprefentation is
fufpended, we can with the greateft facility fuppofe any
length of time or any change of place : the fpedtator, it
is true, may be confcious, that the real time and place
are not the fame with what are employed in the repre-
fentation ; but this is a work of reflection ; and by the
fame refledtion he may alfo be confcious, that Garrick is
not King Lear, that the playhoufe is not Dover cliffs,
nor the noife he hears thunder and lightning. In a
word, after an interruption of the reprefentation, it is not
more difficult for a fpedtator to imagine a new place, or
a different time, than, at the commencement of the play,
to imagine himfelf at Rome, or in a period of time two
thoufand years back. And indeed, it is abundantly ri¬
diculous, that a critic, who is willing to hold candle¬
light for funfhine, and fome painted canvaffes for a
palace or a prifon, fhould affedt fo much difficulty in
imagining a latitude of place or of time in the fable, be¬
yond what is neceffary in the reprefentation. io5
There are, it muft be acknowledged, fome effedls of Great lati-
great latitude in time that ought never to be indulged
in a compofition for the theatre : nothing can be more not
abfurd, than at the clofe to exhibit a full-grown perfontobe in-
who appears a child at the beginning : the mind rejed!:s,dulged,
as contrary to all probability, fuch latitude of time as
is requifite for a change fo remarkable. The greateft
change from place to place hath not altogether the fame
bad effedl : in the bulk of human affairs place is not ma¬
terial j and the mind, when occupied with an intereft-
ing event, is little regardful of minute circumftances:
thefe may be varied at will, becaufe they fcarcely make
any impreffion. JOy
At the fame time, it is not here meant to juftify li-norin
berty without any referve. An unbounded licence with Place*
relation to place and time, is faulty, for a reafon that
feems to have been overlooked, which is, that it feldom
fails to break the unity of adlion : in the ordinary courfe
of human affairs,Tingle events, fuch as are fit to be repre¬
fented on the ftage, are confined to a narrow fpot, and ge¬
nerally employ no great extent of time 5 and according¬
ly we feldom find ftridl unity of adlion in a dramatic com-
pofirion, where any remarkable latitudeisindulged in thefe
particulars. It may even be admitted, that a compofition E/em. of
which employs but one place, and requires not a gxt&iex Criticifm,
length of time than is neceffary for the reprefentation, ischaP- 23*
5H fo
794
T ie three
Unities.
10S
Whether
our drama
be prefer¬
able to
that of
Greece.
P O E
fo much the more petfedl^ beCaitfe the confining an event
within fo narrow bounds, contributes to the unity of ac¬
tion, and alfo prevents that labour, however flight, which
the mind muA undergo in imagining frequent changes of
place, and many intervals of time. Eut ftill we muft in¬
fill:, that fuch limitation of place and time as was necef-
fary in the Grecian drama, is no rule to us 5 and therefore,
that though fuch limitation adds one beauty more to the
compofition, it is at bell but a refinement, which may juftly
give place to a thoufand beauties more fubftantial. And we
may add, that it is extremely difficult, if not impra&ica-
ble, to contracl within the Grecian limits any fable fo fruit¬
ful of incidents in number and variety as to give full fcope
to the fiudluation of paffion.
It may now appear, that critics who put the unities
of place and of time upon the fame footing with the
unity of aclion, making them all equally effential, have
not attended to the nature and conftitution of the mo¬
dern drama. If they admit an interrupted reprefenta-
tion, with which no writer finds fault, it is abfurd to re¬
ject its greateft advantage, that of reprefenting many in-
terefting fubjects excluded from the Grecian Itage. If
there needs mull be a reformation, wffiy not reftore the
ancient chorus and the ancient continuity of adiion ?
There is certainly no medium ; for to admit an interrup¬
tion without relaxing from the ftrift unities of place and
of time, is in effe£t to load us with all the inconveni¬
ences of the ancient drama, and at the fame time to
withhold from us its advantages.
And therefore the only proper queftion is, Whether
our model be or be not a real improvement ? This in¬
deed may fairly be called in queftion ; and in order to a
comparative trial, fome particulars muft be premifed.
When a play begins, we have no difficulty to adjuft our
imagination to the fcene of aftion, however diftant it be
in time or in place ; becaufe we know that the play is a
reprefentation only. The cafe is very different after we
are engaged : it is the perfection of reprefentation to hide
itfelf, to impole on the fpeclator, and to produce in him
an impreffion of reality, as if he wTere fpettator of a real
event; but any interruption annihilates that impreffion,
by roufing him out of his waking dream, and unhappily
reftoring him to his fenfes. So difficult it is to fupport
the impreffion of reality, that much (lighter interruptions
than the interval between two acls arc fufficient to dif-
folve the charm : in the tth aft of the Mourning Bride,
the three firft feenes arc in a room of date, the fourth
in a prifon ; and the change is operated by ffiifting the
fcene, which is done in a trice : but however quick the
tranfition may be, it is imprafticable to impofe upon the
fpeftators fo as to make them conceive that they are ac¬
tually carried from the palace to the prifon ; they imme¬
diately refteft, that the palace and prifon are imaginary,
and that the whole is a fiftion.
From thefe premifes, one will naturally be led, at firft:
view, to pronounce the frequent interruptions in the
modern drama to be an imperfeftion. It will occur,
“ That every interruption muft have the effeft to banifti
the dream of reality, and with it to banifti our concern,
which cannot fubfift while we are confcious that all is a
fiftion ; and therefore, that in the modern drama, fuffi¬
cient time is not afforded for fluftuation and fwelling of
paffion, like what is afforded in that of Greece, where
there is no interruption.” This reafoning, it muft be
T R Y. Part IT.
owned, has a fpecious appearance : but we muft not be- The three
come faint-hearted upon the firft repulfe j let us rally our y Unities
troops for a fecond engagement. y 'J
On the Greek ftage, whatever may have been the
cafe on the Roman, the reprefentation wras never inter¬
rupted, and the divifion by afts was totally unknown.
The word a£i never once occurs in Ariftotle’s Poetics,
in which he defines exactly every part of the drama,
and divides it into the beginning, the middle, and the
end. At certain intervals indeed the aftors retired ;
but the ftage was not then left empty, nor the curtain
let fall 5 lor the chorus continued and fung. Neither
do thefe fongs of the chorus divide the Greek tragedies
into five portions fimilar to our afts ; though fome of
the commentators have endeavoured to force them into
this office. Eut it is plain, that the intervals at which
the chorus fung are extremely unequal and irregular,
fuited to the occafion and the fubjeft j and wmuld divide
the play fometimes into three, fometimes into feven or
eight afts.
As praftice has now eftabliftied a different plan on
the modern ftage, has divided every play into five afts,
and made a total pauie in the reprefentation at the end
of each aft, the queftion to be confidered is, Whether
the plan of the ancient or of the modern drama is beft
qualified for making a deep impreffion on the mind ?
That the preference is due to the plan of the modem
drama, will be evident from the following confiderations.
If it be indeed true, as the advocates for the three uni¬
ties allege, that the audience is deluded into the belief
of the reality of a wrell-afted tragedy, it is certain that
this delufion cannot be long fupported ; for w hen the
fpirits are exhaufted by clofe attention, and by the agi¬
tation of paffion, an uneafinefs enfues, which never fails
to bamlffi the waking dream. Now fuppofing the time
that a man can employ with ftrift attention without
wandering to be no greater than is requifite for a fingle
aft (a fuppofition that cannot be far from truth), it fol¬
low’s, that a continued reprefentation of longer endur¬
ance than an aft, inftead of giving fcope to fluftuation
and fwelling of paffion, would overflrain the attention,
and produce a total abfence of mind. In this refpeft,
the four paufes have a fine effeft : for by affording to
the audience a feafonable refpite wffien the impreflion of
reality is gone, and while nothing material is in agita¬
tion, they relieve the mind from its fatigue ; and conie-
quently prevent a wandering of thought at the very time
poffibly of the moil interefting feenes.
In one article, indeed, the Grecian model has greatly
tire advantage : its chorus, during an interval, not only
preferves alive the impreffions made upon the audience,
but al(b prepares their hearts finely for new impreffions.
In our theatres, on the contrary, the audience, at the
end of every aft, being left to trifle lime awTay, lofe
every warm impreffion ; and they begin the next aft
cool and unconcerned, as at the commencement of the
reprefentation. This is a grofs malady in our theatrical.,
reprefentations \ but a malady that luckily is not incu¬
rable : to revive the Grecian chorus, would be to revive
the Grecian flavery of place and time j but we can fi¬
gure a detached chorus coinciding with a pauie in the
reprefentation, as the ancient chorus did with a paufe
in the principal aft ion. What objeftion, for example,
can there lie againff mufic between the afts, vocal and
inftrumental.
Part II.
The three
Unities.
109
An im¬
provement
of the mo¬
dern dra¬
ma fug-
gefted.
Elem. of
Criticifm,
chap. 23.
no
The mo¬
dern dra¬
ma pre¬
ferable to
the ancient
P O F,
inftrumental, adapted to the fubjed ? Such detached
chorus, without putting us under any limitation of time
or place, would recruit the fpirits, and would preferve
entire the tone, if not the tide, of paflion: the mufic,
after an a£l, fhould commence in the tone of the prece¬
ding paflion, and be gradually varied till it accord with
the tone of the paflion that is to fucceed in the next
aft. The mufic and the reprefentation would both of
them be gainers by their conjunftion ; which will thus
appear. . Mufic that accords with the prelent tone of
mind, is, on that account, doubly agreeable ; and ac¬
cordingly, though mufic fingly hath not power to raife
a paflion, it tends greatly to fupport a paflion already
railed. Further, mufic prepfires us for the paflion that
follows, by making cheerful, tender, melancholy, or ani¬
mated impreflions, as the fubjeft requires. Take for an
example the firit feene of the Mourning Bride, where loft
mufic, in a melancholy ftrain, prepares us for Almeria’s
deep dilfrefs. In this manner, mufic and reprefentation
fupport each other delightfully : the impreflion made
upon the audience by the reprefentation, is a fine prepa¬
ration for the mufic that fucceeds •, and the impreflion
made by the mufic is a fine preparation for the repre¬
fentation that fucceeds. It appears evident, that by
fome fuch contrivance, the modern drama may be im¬
proved, fo as to enjoy the advantage of the ancient cho¬
rus without its flavilh limitation of place and time. But
to return to the comparifon between the ancient and the
modem drama.
The numberlefs improprieties forced upon the Greek
dramatic poets by the conftitution of their drama, may
be fufficient, one Ihould think, to make us prefer the
modern drama, even abftrafting from the improvement
propofed. To prepare the reader for this article, it
muft be premifed, that as in the ancient drama the place
of aftion never varies, a place neceifarily mull; be chofen
to which every perfon may have accefs without any im¬
probability. This confines the feene to fome open place,
generally the court or area before a palace } which ex¬
cludes from the Grecian theatre tranfaftions within
doors, though thefe commonly are the moll important.
Such cruel rellraint is of itfelf fufficient to cramp the
moll pregnant invention •, and accordingly the Greek
wrriters, in order to preferve unity of place, are reduced
to woful improprieties. In the Hippolytus of Euripides
(aft i. fc. 6.), Phaedra, diilreffed in mind and body, is
carried without any pretext from her palace to the
place of aftion ; is there laid upon a couch, unable to
fupport herfelf upon her limbs 5 and made to utter many
things improper to be heard by a number of women
who form the chorus : and what is Hill more improper,
her female attendant ufes the ftrongeft intreaties to
make her reveal the fecret caufe of her anguifli *, which
at laft Phaedra, contrary to decency and probability, is
prevailed upon to do in prefence of that very chorus
(aft ii. fc. 2.). Alcelles, in Euripides, at the point of
death, is brought from the palace to the place of aftion,
groaning and lamenting her untimely fate (aftii. fc. 1.).
In the Trachinice of Sophocles (aft ii.), a fecret is im¬
parted to Dejanira, the wife of Hercules, in prefence of
the chorus. In the tragedy of Tphigenia, the meffenger
employed to inform Clytemnellra that Iphigenia was fa-
crificed, flops fhort at the place of aftion, and with a
loud voice calls the queen from her palace to hear the
T R Y-  795
news. Again, in the Iphigenia in Tauris (aft iv.), the Thethiee
neceffary prefence of the chorus forces Euripides into a Unities,
grofs abfurdity, which is to form a fecret in their hear- v
ing and, to difguife the abfurdity, much court is paid
to the chorus, not one woman but a number, to engage
them to fecrecy. In the Medea of Euripides, that prin-
cefs makes no difficulty, in prefence of the chorus, to
plot the death of her hulband, of his miilrefs, and of her
father the king of Corinth, all by poifon : it was ne-
ceflary to bring Medea upon the tlage j and there is
but one place of aftion, which is alwrays occupied by
the chorus. This feene clofes the fecond aft } and in
the end of the third, fhe frankly makes the chorus her
confidants in plotting the murder of her own children.
Terence, by identity of place, is often forced to make
a converfation within doors be heard on the open flreet:
the cries of a woman in labour are there heard di-
. lir
The Greek poets are not lefs hampered by unity ofjnconve.
time than by that of place. In the Hippolytus of Euri- niences of1
pides, that prince is banifhed at the end of the 4ththe Plan
aft } and in the firll feene of the following aft, a mef-
fenger relates to Thefeus the whole particulars of the ma<
death of Hippolytus by the fea-monfter : that remark¬
able event mull have occupied many hours 5 and yet in
the reprefentation it is confined to the time employed
by the chorus upon the fong at the end of the 4th aft.
The inconfiftency is Hill greater in the Iphigenia in Tau¬
ris (aft v. fc. 4.) : the fong could not exhauft half an
hour •, and yet the incidents fuppofed to have happened
during that time could not naturally have been tranfaft-
ed in lefs than half a day.
The Greek arthls are forced, not lefs frequent:v. to
tranfgrefs another rule, derived alio from a continued
reprefentation. The rule is, that as a vacuity, however
momentary, interrupts the reprefentation, it is neceiiarc
that the place of aftion be conftantly occupied. So¬
phocles, with regard to that rule as well as to others, is
generally correft : but Euripides cannot bear fuch re-
ftraint *, he often evacuates the fiage, and leaves it empty
for others. Iphigenia in Tauris, after pronouncing a
foliloquy in the firll feene, leaves the place of aftion,
and is fucceeded by Orefies and Pylades : they, after
fome converfation, walk off; and Iphigenia re-enters,
accompanied with the chorus. In the Alceftes, which
is of the fame author, the place of aftion is void at the
end of the third aft. It is true, that to cover the irre¬
gularity, and to preferve the reprefentation in motion,
Euripides is careful to fill the ilage without lofs of time :
but this Hill is an interruption, and a link of the chain
broken : for during the change of the aftors, there mult
be a fpace of time, during which the ftage is occupied
by neither fet. It makes indeed a more remarkable in¬
terruption, to change the place of aftion as wTell as the
aftors ; but that was not prafticable upon the Grecian
ftage.
It is hard to fay upon what model Terence has form¬
ed his plays. Having no chorus, there is a paufe in the
reprefentation at the end of every aft : but advantage is
not taken of the ceffation, even to vary the place of ac¬
tion •, for the ftreet is always chofen, where every thing
palling may be leen by every perfon j and by that
choice, the moll fprightly and interefting parts of the
aftion, which commonly pafs within doors, are exclud"-
5 H 2 ed ;
796
The three
Unities.
Elem. of
Criticifn,
chap. aj.
No change
of time or
place to
be admit¬
ted hut be¬
tween the
a<Ts.
POE
ed; witnefs the la A: a cl of the Eunuch. H e hath fab-
milted to the like flavery with refpeft to time. In a
word, a play with a regular chorus, is not iruare confined
in place and time than his plays are. Thus a zealous
feclary follows implicitly ancient forms and ceremonies,
without once coniidering whether their introdu£live
caufe be itill fubfifting. Plautus, of a bolder genius
than Terence, makes good ufe of the liberty afforded by
an interrupted reprefeniation he varies the place of ac¬
tion upon all occafions, when the variation lints his pur-
pofe.
The intelligent reader will by this time underftand,
that we plead tor no change of place in our plays but
after an interval, nor for any latitude in point of time
but what falls in with an interval. The unities of place
and time ought to be llriftly obferved duiing each aft }
for during the seprefentation there is no opportunity for
the fmalleil deviation from either. Hence it is an effential
requifite, that during an aft the ftnge be always occu¬
pied 3 for even a momentary vacuity makes an interval
or intenuption. Another rule is no lefs effential : it
would be a grofs breach of the unity of aftion to exhibit
upon the ft age two feparate actions at the fame time j and
therefore, to preferve that unity, it is neceffary that each
perlbnage introduced during an aft be linked to thole in
pofleffion of the ftage, lb as to join all in one aftion. Thefe
things follow from the very conception of an aft, which
admits not the flighted: interruption : the moment the re-
prefentation is intermitted, there is an end of that aft 5
and we have no other notion of a new aft, but where,
after a paufe or interval, the reprefentation is again put
in motion. French writers, generally fpeaking, are cor-
reft in this particular. The Englifh, on the contrary,
are fo irregular as fcarce to deferve a criticifm 5 aftors
not only fucceed each other in the fame place without
conneftion, but, w'hat is ftill lefs excufable, they fre¬
quently fucceed each other in different places. T his
change of place in the lame aft ought never to be indul¬
ged 3 for, befide breaking the unity of the aft, it has a
difagreeable effeft : after an interval, the imagination
adapts itfelf to any place that is necefiary, as readily as
at the commencement of the play •, but during the re¬
prefentation we rejeft change of place. From the fore¬
going cenfure muft be excepted the Mourning Bride of
Congreve, where regularity concurs with the beauty of
fentiment and of language, to make it one of the molt
complete pieces England has to boaft of. It is acknow¬
ledged, however, that in point of regularity this elegant
performance is not altogether unexceptionable. In the
four firft afts, the unities of place and time are ftriftiy
obferved : but in the laft aft, there is a capital error
with refpeft to unity of place ; for in the three firfl:
feenes of that aft, the place of aftion is a room of ftate,
which is changed to a prifon in the fourth feene : the
chain alfo of the aftors is broken j as the perfons intro¬
duced in the prifon are different from thofe who made
their appearance in the room of ftate. This remarkable
interruption of the reprefentation makes in effeft two afts
inllead of one : and therefore, if it he a rule that a play
ought not to confift of more afts than five, this perform¬
ance is fo far defeftive in point of regularity. It may be
added, that, even admitting fix afts, the irregularity would
not be altogether removed, without a longer paufe in the
reprefentation than is allowed in the afting; for more than
R Y.
Part XI.
Of the
Opera.
**3
a momentary interruption is requifite for enabling the ima¬
gination readily to fall in with a new place, or with a wide
ipace of time. In The Waij of the World, of the fame au¬
thor, unity of place is preferved during every aft, and a
itrifter unity of time during the whole play than is necel-
fary.
§ 4. Of the Opera.
An opera is a drama reprefented by mufic. This en- -n „
r • t -rr • J a 1 • t he opera,
tertamment was invented at Venice. An exhibition ora drama mr
this fort requires a moll brilliant magnificence, and anpiefeuted
expence truly royal. The drama muft neceffarily be A H1U^C>
compofed in verfe ; for as operas are lung and accom¬
panied with fymphonies, they muft be in verfe to be pro¬
perly applicable to mufic. To render this entertainment
liill more brilliant, it is ornamented with dances and
ballets, with fuperb decorations, and furprifing ma¬
chinery. The dreffes of the aftors, of thole who alii it
in the chorus, and of the dancers, being all in the moll
fplendid and elegant talxe, contribute to render the ex¬
hibition highly fumptuous. But notwithftanding this
union of arts and pleafures at an immenfe expence, and
notwithftanding a molt dazzling pageantry, an opera
appears, in the eyes of many people of talte, but as a
magnificent abfurdity, feeing that nature is never there
from the beginning to the end. It is not our bufinels
here, however, to determine between the different taftes
of mankind.
The method of exprelling our thoughts by finging
and mufic is fo little natural, and has fomething in it
lb forced and affefted, that it is not eafy to conceive
how it could come into the minds of men of genius to
reprefent any human aftion, and, what is more, a feri-
ous or tragic aftion, any otherwife than by fpeech. We
have, it is true, operas in Englilh by Addifon, &c. in
Italian by Metaftafio, in French by M. Quinault, Fon-
tenelle, &c. the fubjefts of which are fo grave and tra¬
gic, that one might call them mufical tragedies, and real
chefs d'ceuvres in their kind. But though wre are high¬
ly fatisfied and greatly affefted on reading them, and
are much pleafed with feeing them reprefented, yet the
fpeftator is, perhaps, more charmed with the magnifi¬
cence of the fight and the beauty of the mufic, than
moved with the aftion and the tragical part of the per¬
formance. We are not, however, of that order of erh
tics who ftrive to prove, that mankind aft wrong in
finding pleafure in an objeft with which they are really
pleafed ; wdio blame a lover for thinking his miftrefs
charming, when her features are by no means reg\x\rdx ^BieJfielcVs
and who are perpetually applying the rules of logic to Elem. of
the works of genius: we make thefe obfervations mere- Erudition*
ly in order to examine if it be not pcflible to augment
the pleafures of a polite people, by making the opera
fomething more natural, more probable, and more con-
fonant to reafon. Jr^
We think, therefore, that the poet (hould never, or/houlci take
at leaft very rarely, choofe a fubjeft from hiftory, buftts lubjedt
from fable or mythology, or from the regions of en-not Am
chantment. Every rational mind is conftantly fhock- qj^/abie1
ed to hear a mutilated hero trill out, from the fienderand en_
pipe of a chaffinch, To arms! To arms! and in theshantment.
fame tone animate his foldiers, and lead them to the af-
fault 3 or harangue an affembly of grave fenators, and
fpmetimes a whole body of people. Nothing can be
more
Part II.
F O E
Ot the more barlefque than fuch exliibilions j and a man mud:
% °I]efa- be poiTefTea of a very uncommon fenfibility to be
_v '"IJ— affcded by them. But as we know not what was the
language of the gods, and their manner of exprefling
theiufelves, we are at liberty in that cafe ta form what
illufions we pleafe, and to fuppofe that they fung to
diltinguifh themfelves from mortals. Befides, all the
magic of decorations and machinery become natural,
and even necefTiry, in thefe kinds of fubje&s and
therefore readily afford opportunity for all the pomp of
thefe performances. The chorus, the dances, the bal-
lettes, the fymphonies and dreffes, may likewife be all
made to correfpond with fuch fubjefts, nothing is here
a fie died, abfurd, or unnatural. Whoever is pofTeffed
of genius, and is well acquainted with mythology,
will there find an inexhauftible fource of fubjecls
highly divevfified, and quite proper for the drama of an
opera.
We fhall not fpeak here of that fort of multc which
appears to us the mofl proper for fuch a drama, and
of the feveral alterations of which we think it fufeep-
tible, in order to make it more complete, and to adapt
it to a more pathetic, more noble, and more natural
expreflion, as well in the recitatives as in the airs and
chorus.* (See Music). W e have only here to confider
the bufinefs of the poet. He fliould never lofe fight
of nature, even in the midft of the greateft 66Hon. A
n$ g°d, a demi-god, a renowned hero, fiich for example
and Ihould as Renaud in Armida, a fairy, a genii, a nymph, or
re prefen t fury, &.c. fliould conftantly be reprefented according
its c arac- to the characters we give them, and never be made to
fident. talk, the language ora top or a petite maitreffe. I he
recitative, which is the ground-work of the dialogue,
requires verfes that are free and not regular, fuch as
with a fimple cadence approach the neareft to common
language. The airs fliould not be forced into the piece,
nor improperly placed for the fake of terminating a
feene, or to difplay the voice of a performer : they
fhould exprefs fome fentiment, or fome precept, fhort
and ftriking, or tender and affe&ing ; or fome fimile
lively and natural ; and they fhould arife of themfelves
from a monologue, or from a feene between two per-
fons: prolixity fhould here be particularly avoided,
efpecially when fuch an air makes part of a dialogue j
for nothing is more infipid or difguftful than the coun¬
tenances of the other aCtors who appear at the fame
time, whofe filence is quite unmeaning, and who know
not what to dovwith their hands and feet while the
finger is flraining his throat. The verfe of all the airs
fliould be of the lyric kind, and fhculd contain fome
poetic image, or paint fome noble paflion, which may
furnifli the compofer with an opportunity of difplaying
bis talents, and of giving a lively and affe&ing expref-
fion to the mufic.' A phrafe that is inanimated can never
have a good effefl in the performance, but mull become
infipid and horribly tedious in the air. The trite fimi-
lies of the Italians, of a fiream that flows, or a bird that
flies, &c. are no longer fufferable. The fame thing
may be faid with regard to the chorus, which fliould be
equally natural and well adapted : it is here fometimesa
whole people, fome times the inhabitants of a peculiar
country, and fometimes warriors, nymphs, or priefts, &c.
who raife their voice to demand juftice, to implore fa¬
vour op render a general homage. The action itfelf
T R Y. 797
will furnifh the poet of genius with ideas, words, and the Of the
manner of difpofing them. , Opera-
Laflly, the opera being a performance calculated lefs v ^
to fatisfy the underflanding than to charm the ear and
affedl the heart, and efpecially to ftrike the fight, the
poet fliould have a particular attention' to that objeft,
fliould be Added in the arts of a theatre, fliotdd know
how to introduce combats, ballets, feafls, games, pom¬
pous entries, folemn proceflions, and fuch marvellous in¬
cidents as occur in the heavens, upon earth, in the fea,
and even in the infernal regions: but all thefe matters
demand a ftrong chara£ler, and the utmoff precifion in
the execution : for otherwife, the comic being a near
neighbour to the -fublime, they will eafily become ridi¬
culous. The unity of action muft certainly be obferved Un-” of.
in fuch a poem, and all the incidental epifodes muft con- adtion ne-
cur to the principal defign j otherwife it would be a cefiary to
monftrous chaos. It is impoflible, however, ferupu-^ 0Pera*
loufly to obferve the unity of time and place: though,
the liberty, which reafon allows the poet in this refpecl,
is not without bounds j and the lefs ufe he makes of it,
the more perfect his poem will be. It is not perhaps
impofTible fo to arrange the objects, that, in changing
the decorations, the painter may conftantly make ap¬
pear fome part of the principal decoration which cha-
rafterifes the fituation of the feene, as the corner of a
palace, at the end of a garden, or fome avenue that
leads to it, &c. But all this is liable to difficulties,
and even to exceptions; and the art of the painter muft
concur in fuch cafe with that of the poet. For the reft,,
all the operas of Europe are at leafl one third too
long; efpecially the Italian. The unity of aftion re¬
quires brevity, and fatiety is infeparable from a diver-
fion that lafts full four hours, and fometimes longer.
They have indeed endeavoured to obviate this incon*
venience by dividing an opera into three, and even into
five a61s; but experience proves, that this divifion,
though judicious, is fiill not fufficient to relieve the wear
tied attention.
Sect. II. Of Lyric Poetry*
The. ode is very ancient, and w^as probably the firft origin 0f
fpecies of poetry. It had its fource, we may fuppofe, the eds.
from the heart, and w7as employed to exprefs, with be¬
coming fervour and dignity, the grateful fenfe man
entertained of the blefllngs which daily flowed from
God the fountain of all goodnefs : hence their har-
veft hymns, and other devotional compofitions of that
kind.
But in procefs of time it was employed, not only to
praife- the Almighty for bounties received, but to folicit
his aid in time of trouble; as is plain from the odes
written by King David and others, and colle61ed by the •
Jewifh Sanhedrim into the book, of PfaliESj to be fung
at their fails, feftivals, and on other folemn occafior.s.
Nor was this pradlice confined to the Ifraelites only :
other nations had their fongs of praife and petitions of
this fort, which they preferred to their deities in time
of public proiperity and public diftrefs* as well as to
thofe heroes who diftinguiihed themfelves in arms.
Even the American Indians, whofe notions of religion
are extremely confined, have their war Tongs, which, they
fing to this day..
Ik
798 POE
Of Lyric It is reafonable to fuppofe that th? awful purpofe to
, 1J°etlT _ which the ode was applied, gave rife among the ancients
to the cuftom of invoking the mufes •, and that the poets
in order to raife their fentiments and language, fo as to
be acceptable to their deities, thought it expedient to
folicit fome divine aflillance. Hence poets are faid to
have been infpired, and hence an unbounded liberty has
been given to the ode j for the lyric poet, fired, as it
were, with his fubjeft, and borne away on the wings of
gratitude, difdains grammatical niceties and common
IlS modes of fpeech, and often foars above rule, though not
Its free- above reafon. This freedom, however, confids chiefly
dom. in hidden tranfitions, bold digreflions, and lofty excur-
fions. For the ancient poets, and even Pindar, the naoft
daring and lofty of them all, has in his fublimeft flights,
and amidfl; all his rapture, preferved harmony, and often
uniformity in his verfification : but fo great is the vari¬
ety of his meafures, that the traces of famenefs are in a
manner loft } and this is one of the excellencies for which
that poet is admired, and which, though feemingly de¬
void of art, requires fo much that he has feldom been
imitated with fuccefs.
The ancients in their odes indulged fuch a liberty of
fancy, that fome of their beft poets not only make bold
excurfions and digreflions, but, having in their flights
ftarted fome new and noble thought, they frequently
purfue it, and never more return to their fubjedt. But
this loofe kind of ode, which feems to rejeft all method,
and in which the poet, having juft touched upon his
fubjeft, immediately diverts to another, we ihould think
blameable, were it lawful to call in queftion the autho¬
rity of thofe great men who were our preceptors in this
art. We may venture to affirm, however, that thefe
compofitionsftand in no degree of comparifon with other
odes of theirs 5 in which, after wandering fronufche fub-
je£t in purfuit of new ideas arifing from fome of its ad-
j units, and ranging wantonly, as it were, through a va¬
riety of matter, the poet is from fome other circumftance
led naturally to his fubjeit again 5 and, like a bee, ha¬
ving collected the efience of many different flowers, re¬
turns home, and unites them all in one uniform pleafing
1x9 fweet.
The fub- The ode among the ancients fignified no more than a
oftk® fong : but with the moderns, the ode and the fong are
0 e* confidered as different compofitions } the ode being ufu-
ally employed in grave and lofty fubjeits, and feldom
fung but on folemn occafions.
The fubjeils moft proper for the ode and fong, Ho¬
race has pointed out in a few elegant lines.
Gods, heroes, conquerors, Olympic crowns,
Love’s pleafing cares, and the free joys of wine,
Are proper fubjeils for the lyric fong.
To which we may add, that happinefs, the pleafures
of a rural life, and fuch parts of morality as afford lef-
fons for the promotion of our felicity, and reflexions on
the conduft of life, are equally fuitable to the ode. This
both Pindar and Horace were fo fenfible of, that many
of their odes are feafoned with thefe moral fentences and
refleflions.
But who can number ev’ry fandy grain
Wafti’d by Sicilia's hoarfe-refounding main ?
T R Y. Part II.
Or who can Titer on's gen’rous works exprefs, Of Lyric
And tell how many hearts his bounteous virtues blefs ?, ^try- t
Ode to Theron. " h *
And in another Olympic ode, infcribed by the fame
poet to Diagoras of Rhodes (and in fuch efteem, that
it was depofited in the temple of Minerva, written in
letters of gold), Pindar, after exalting them to the Ikies,
concludes with this leflbn in life :
Yet as the gales of fortune various blow,
To-day tempeftuous, and to-morrow fair,
Due bounds, ye Rhodians, let your tranfports know \
Perhaps to-morrow comes a ftorm of care.
Weft's Pindar.
The man refolv’d and fteady to his truft,
Inflexible to ill, and obftinately juft,
May the rude rabble’s infolence defpife,
Their fenfelefs clamours and tumultuous cries ;
The tyrant’s fiercenefs he beguiles,
And the ftern brow and the harfli voice defies.
And with fuperior greatnefs fmiles.
Not the rough whirlwind, that deforms
Adria’s black gulf, and vexes it with ftorms,
The ftubborn virtue of his foul can move $
Nor the red arm of angry Jove,
That flings the thunder from the Iky,
And gives it rage to roar, and ftrength to fly.
Should the whole frame of nature round him break,
In ruin and confufion hurl’d,
He unconcern’d would hear the mighty crack,
And ftand fecure amidft a falling world.
Horace.
M. Defpreaux has given us a very beautiful and juft
defcription of the ode in the following lines.
L’Ode avec plus d’eclat, & non moins d’energie
Elevant jufqu’au ciel fon vol ambitieux,
Entretient dans vers commerce avec les Dieux.
Aux Athletes dans Pife elle ouvre la barriere,
Chante un vainqueur poudreux au bout de la carriere;
Mene Achille fanglant au bords du Simois
Ou fait flechir 1’Efcaut fous le joug de Louis.
Tantot comme une abeille ardente a fon ouvrage
Elle s’en va de fleurs depouiller le rivage :
Elle peint les feftins, les danfes & les ris,
Vante un baifer cueilli fur les levres-d’Iris,
Qui mollement refifte & par un doux caprice
Quelquefois le refufe, afin qu’on le ravifle.
Son ftyle impetueux fouvent marche au hafard.
Chez elle un beau defordre eft un effet de Part,
Loin ces rimeurs craintifs, dont 1’efprit phlegmatique
Garde dans fes fureurs un ordre didaXique :
Qui chantant d’un heros les progres eclatans,
Maigres hiftoriens, fuivront 1’ordre des temps.
Apollon de fon feu leur fut toujours avare, &c.
The lofty ode demands the ftrongeft fire,
For there the mufe all Phoebus muff: infpire :
Mounting to heav’n in her ambitious flight,
Amongft the gods and heroes takes delight j
Of Pi fa’s wreftlers tells the finewy force,
And fings the dufty conqueror’s glorious courfe;
To
4
Part II.
O Lyric
Poetry.
POE
To SImois’ banks now fierce .Achilles fends,
Beneath the Gallic yoke now Efcaut bends :
Sometimes (he flies, like an induftrious bee,
And robs the flow’rs by nature’s chemiflry ;
Defcribes the fhepherds dances, feafts, and blifs,
And boafts from Phillis to furprife a kifs,
When gently fhe refifts with feign’d remorfe,
That wThat five grants may feem to be by force.
T R Y.
Her generous ilyle will oft at random Hart,
And by a brave diforder fhow her art ;
Unlike thofe fearful poets w’hofe cold rhyme
In all their raptures keeps exadleif time,
Who ling th’ illuftrious hero’s mighty praife,
Dry journalifts, by terms of weeks and days j
To thefe, Apollo, thrifty of his fire,
Denies a place in the Pierian choir, &c.
799
Of Lyric
Poetry.
So AMES,.
POETRY continued in next Volume*
END OF THE SIXTEENTH VOLUME.
DIRECTIONS 1 or placing the PLATES of Vol. XVL
Part I.
Plate CCCCIV.—CCCCVI. to face
CCCCVII.
CCCCVIIL
ccccrx.
CCCCX.—ccccxv.
CCCCXVL
page 32
92
- 114
128
184
SS6
Part II,
-CCCCXVII. CCCCXVIII.
CCCCXIX.
CCCCXX—CCCCXXII.
ccccxxm—ccccxxxiii.
52S
552
6oo
75°
,*'***“ -