>IFT OF
POPULAR ASTRONOMY.
A DESCRIPTION
OF THE
PEINCIPAL PHENOMENA
ASTRONOMY:
. INCLUDING
THE SUN; THE SOLAR SYSTEM; PLANETS; THE EARTH AND
ITS ATMOSPHERE; THE SEASONS; THE MOON AND ITS
PHASES; DAY AND NIGHT; ECLIPSES; "TIDES j STARS;
NEBULAE &c.
LONDON:
PUBLISHED BY JAMES REYNOLDS, 174, STRAND.
I $
POPULAR ASTRONOMY.
IN giving a brief sketch of the principal phenomena of Aslroauiny, it will be de-
sirable to commence with a description of the Solar System.
^THE SOLAR SYSTEM comprises the sun, eight principal planets, and thirty-five
minor planets ; all of -which revolve round the sun as their centre, and are termed
primary planets ; in addition to these, it also comprises a number of secondary
planets or moons, which revolve round some of the primary planets ; and an unknown
number ot bodies called comets.
THE SUN.
The Sun forms the centre of the planetary system, and is a round opaque body,
surrounded by a luminous atmosphere, adapted to supply heat and light to all the
planets. The sun is distant from the earth about ninety-five million miles ; his dia-
meter is 882,000 miles ; and Jus vojumeor bulk. 1,?QO,QOO times greater than that of
the earth. The sun rotates updn/his axJ ifl IJwOqty-fivf days eight hours.
Upon looking at the sun thrbugh'a telescope; h^vnig* coloured glasses, a number
of dark spots are usually seen upon its surface. If these spotsbe repeatedly watched,
they will be found not to b slatiorjaay^o"^ ttte! sun's ."dis fot'*any long period of time,
nor to remain of the sasae shap'ei haf fc> vary'tlleir pogitipn, to contract or enlarge^
and at times suddenly to *dfsap*pfeaf ; ' while 'otters* brea*k* out in places where none
beforeexisted. The size of some of the spots is immense; in the year 1758, one
was observed which measured 45,000 miles across : indeed, the least possible spot
which can be seen by our best glasses, cannot be less than 465 miles in diameter.
The result of the investigations into this subject is, that the solar spots are believed
to be spaces or openings through the luminous matter, exposing to view portions of
the solid body of the sun. By an attentive observer it will be remarked, that such
of the spots as remain stationary for a considerable time, have a gradual motion,
apparently across the sun's disk. This motion of the spots can only arise from the
rotation of the sun on his axis; and they serve to mark the time of this rotation.
These spots also prove that the sun is a spherical body ; for a spot makes its appear-
ance on the western edge of the sun as a fine line, which gradually increases n
breadth tiil it approaches the centre. As it passes on to the eastern edge, its dia-
meter gradually lessens into a fine line, before it entirely vanishes from view.
With regard to the question, whether or not the sun is inhabited, astronomers are
undecided. Sir William Hershel, from what he had observed in that luminary,
states as follows : " The sun appears to be nothing else than a very eminent, large,.
and lucid planet ; evidently the first, or rather, the only primary one of our system,
all the rest being secondary to it. Its similarity to the other globes of the solar
system, with regard to its solidity, its atmosphere, and its diversified surface, leads
us to suppose that it is most probably also inhabited, like the rest of the planets, by
beings whose organs are adapted to the peculiar circumstances of that vast globe."
Owinj* to the great difference in the distances of the various planets from toe sun
and which will be described presently, it will be evident that he must present to their
various inhabitants different degrees of magnitude. Thus, to Mercury, he appears
as a globe far larger than he does to us, while to the inhabitants of Neptune, he
must appear little larger than a star point. The former planet being only 37 mil
lions of miles distant from him, while the latter view him from the enormous distance
of 2,800 millions.
THE PLANETS
Round the sun revolve tne planets, in orbits not circular, but more or less ellip-
tical or oval. The planets are opaque, solid, globular bodies, which receive their
light and heat from the sun ; they all rotate upon their axis, and consequently, all
enjoy the alternations of day and night. Their axis is also more or less inclined to
the plane of their orbit ; they therefore experience, to a greater or less degree, the
vicissitudes of the seasons. The planets are retained in their orbits by the com-
pound action of two mutually opposing forces : first, the centrijieial force, or ra-
vitation, by which a body is attracted towards the centre of gravity, which, in the
case of the planets, is the sun ; and, secondly, the centrifugal f<>rce, by which a body
in motion tends to proceed in a straight line. Thus, if a body be acted upon by
two forces impelling it in different directions, the body will obey neither, but take a
direction compounded of both, or between the two. It is the action then of this
universal law which retains the planetary bodies in their appointed orbits.
Several of the planets are accompanied by satellites or moons, which supply light,
by reflection from the sun during his nightly absence, to their primaries. The
sa;ellites revolve round their primaries, and accompany them in their revolution round
the sun. Between the orbits of Mars and Jupiter have been discovered a number of
small planets, which are all classed under the term MINOR PLANETS. Their exis-
tence was unknown before the commencement of the present century ; but at this
time we are acquainted with thirty-five, and probably more may yet be discovered.
MERCURY. This planet is, with the exception of the minor planets, the smallest
in the system, at the same time he is the most compact celestial body with which we
are acquainted. His density is about fourteen times that of water, or more than
equal to that of lead. On account of his small size and proximity to the sun, Mer-
cury is seldom distinctly seen, but with a good telescope he may sometimes be dis-
covered a little before sunrise and after sunset. The telescopic appearance of
Mercury is that of a planet having phases, or assuming that alternate increase and
decrease of form under which we see the moon, except that Mercury does not appear
quite full to us. The powerful telescopes of modern times have discovered to us
spots on the surface of this planet by means of which his axial motion has been
ascertained, and found to be 24 hours 5 minutes and 28 seconds; thus his day is
nearly the same length as our own. His year, however, consists only of 88 days,
being the period in which he completes his revolution round the sun, so that bis
seasons will each consist of only three or four weeks.
VENUS. This is the brightest of the planets, and as she is usually visible at the
time of sunrise and sunset, she has received the name of the morning and evening
star. Venus would appear to be the sister globe to the earth ; her diameter differs
only by 200 miles from that of our own planet; her day only by a few minutes ;
she is surrounded, like the earth, with an atmosphere, through which clouds and
vapours float, indicating the existence of water beneath, from which they derive their
origin ; her surface is also diversified by mountains of vast height. The matter of
this planet is supposed to be somewhat denser than that of the earth.
The phenomena of the seasons, which depend (as we shall hereafter explain) upon
the inclination of the axis of a planet to the plane of its orbit, are peculiar in the
case of Venus. Her axis is inclined about 75 degrees to her orbit, and as the decli-
nation of the sun on each side of the equator is equal to the inclination of her axia,
her tropics are only 15 degrees from her poles, and her polar circles at the same
distance from her equator. The variations of her seasons is so frequent that she
has two winters, springs, summers, and autumns in each of her annual revolutions.
Venus exhibits the various lunar phases, except that she never appears quite full ;
for when the whole of her enlightened side is turned towards us, in her superior
conjunction, the solar rays interfere with her splendour. Her course is as follows:
Soon after her inferior conjunction, when she passes between the sun and the earth,
we behold Venus as a morning star, rising a little before the sun, exhibiting a fine
silver crescent. She gradually gains upon the luminary, rises more and more before
him, till her greatest angular distance westward is attained, when she appears a
semi- circle. Proceeding to her superior conjunction, she apparently returns to the
sun, rises later and later, appears gibbous, and then nearly full. On the east of the
sun Venus becomes an evening star, visible for a short time after his setting.
Passing to her eastern elongation, she sets later every night, and her appearance is
gradually reduced to a semi-circle j after which, returning to the sun, she becomes
a crescent, sets with him, and is invisible, the unenlightened half of the orb being
towards us. In a few days the phenomena of the morning star are repeated.
Deferring for the present the description of the earth, we will pass on to ^the next
planet in order of distance from the sun.
MARS. This planet, which has its orbit exterior to that of the earth, is about
one half the diameter of the latter. He sometimes presents a gibbous, and, at
other times, a circular appearance. He possesses an atmosphere which is very
dense, and of considerable extent. From the nature of this atmosphere arises, in
part, perhaps, the red colour which distinguishes this planet; tuough this may be
M97533
caused by the ochry tinge of the soil beneath. Clear indications of continents and
seas are disclosed by the telescope, the seas presenting a greenish hue. A brilliant
white district from time to time is observed in the neighbourhood of his north
pole, which decreases in size when it is turned towards the sun. It is highly pro-
1 bable that this is the accumulations of snow and ice formed during his long polar
winters of twelve months duration, which melt before the sun as the summer
season returns. The axis of Mars is inclined to the ecliptic about 30 degrees 18
minutes; hence his seasons must be very similar to those of the earth, but of
different length ; he has also nearly the same intervals of day and night as we
have.
THE MINOR PLANETS. Next in order of distance, we come to the group of
minor planets, or asteroids. They are exclusively telescopic objects, and require
very powerful instruments to be discerned. The brightest in the group is Vesta,
which appears like a star of the fifth magnitude. The dimensions of these planets,
although not accurately ascertained, is comparatively small ; Vesta is computed to
be only 250 miles in diameter, and Pallas is supposed to be much smaller. Their
orbits are much more eccentric than those of the other planets.
JUPITER. We now come to the first of a group of planets distinguished for
their vast magnitudes, their rapidity of rotation, their comparative lightness, and
the enormous extent of their circuits.
Next to the sun, the planet Jupiter forms the most magnificent body in our
system. His great size, being nearly 1,300 times the volume of the earth, the
clearness of his light, and his accompaniment of moons, render him a most agree-
able object for telescopic observation. The density of Jupiter is little more than
that of water, so that the quantity of matter contained in his enormous volume is
only equal to about 331 times that of the earth; and it is computed that a liquid
on Jupiter, which would be analogous to our oceans, would be three times lighter
than sulphuric aether, and would be such that cork would scarcely float on it. The
axis of Jupiter being nearly perpendicular to the plane of his orbit, there is no
change in the seasons, but perpetual summer at his equator, and winter at the poles.
The velocity of his rotary motion is enormous, being at the rate of 28,000 miles
an hour. His day is less than ten hours ; but his year is equal to nearly twelve
of ours.
The belts of Jupiter are certain streaks across his disk, running parallel to his
equator ; they are not fixed or regular either in size or number, but are observed to
vary, to run into each other, and sometimes suddenly to disappear. They are
supposed to be clouds floating in the atmosphere of the planet ; or rather, perhaps,
the darker body of the planet appearing through the atmosphere.
The distinguishing feature of the planet Jupiter is his being accompanied by
four moons, which revolve round him in periods of time varying from 1 day 18
hours, to 16 days. The moons of Jupiter form, with the planet as a central body,
a planetary systam in miniature ; the first and fourth are about the siz.e of Mercury;
the second and third about the size of our moon.
SATURN. This planet, the most remarkable body in the system in point of
architecture, is nearly twice the distance of Jupiter from the sun ; or, at the mean
distance of 900,000,000 miles.
Saturn rotates upon his axis in 10 hours 29 minutes, forming his day ; and com-
pletes his revolution round the sun in 29g of our years, forming one of his. Next
to Jupiter, he is by far the largest of the planets, having a diameter of 76,000
miles, and a bulk equal to nearly a thousand times that of the earth. The density
of Saturn is little more than that of cork. Although never seen by us at a point
nearer than 800,000,000 miles, Saturn shines to the naked eye, with a pale, feeble,
jet steady light ; but becomes one of the most fascinating objects in the heavens
as seen with the telescope. The body of this planet is encompassed with an inner
and outer ring, resembling the horizon round a globe, but at a greater comparative
distance. The width of the double ring is computed at 30,000 miles ; and the
space between the inner ring and the body of the planet 19,000 miles. The figure
of Saturn is the flattest of all the planets at the poles, for in addition to the cen-
trifugal force generated by his rapid rotation, the attraction of the rings over the
equator has aided the accumulation of matter in that region.
Saturn exhibits belts like Jupiter, indicating an atmosphere ; his seasons, zones,
find climates, ure similar to those of the earth, and the tropical and polar pheno-
mena are the same. Of his satellites little is known, they require very powerful
telescopes to reach them.
URANUS. Since the time of the discovery of this planet by the illustrious Her-
tehel, little has been added to our knowledge of him. He is certainly attended by
t least four satellites, possibly more, and their revolutions are performed iti a
direction contrary to the general movements of the planetary system, from west to
east; while the inclination of their paths to the ecliptic,- one oi "which forms an
angle of only 11 deg. 2 min. with a perpendicular to it-s plane, is another deviation
from what would seem to be the existing arrangement with all the other planets,
except Neptune.
NEPTUNE. This, the most distant of the known planets in the solar system, was
discovered by Messrs. Adams and Le Verrier, in 1846. He revolves at tue vast
distance of 2,862 millions of miles from the sun, and occupies 164 years in per-
forming his vast circuit round that luminary, although he travels at the rate of
12,500 miles an hour. The discovery of a satellite to this remote planet is due to
Mr. Lassel, of Liverpool ; and it is found to travel in the same retrograde order as the
satellites of Uranus.
COMETS
Besides the planets already described, there is an unknown, number of other
bodies, called COMETS, which revolve round the sun in very elliptical orbits. Their
period of revolution is so long that very little is known respecting them. They
are only seen by us when they are in that part ot their orbits which is nearest the
sun, and then they move with such vast rapidity that they soon become again in-
visible to us. They are not all alike in appearance ; some appear like a faint
vapour, while others have a solid part in the middle. When they approach the sun,
they have a tail of luminous matter, which is sometimes of astonishing length,
and always directed from the sun.
The conjectures of many eminent astronomers respecting the nature and causes
of the tails of comets, show that they are not yet understood. Some have thought
that it was the atmosphere of the comet driven behind it by the force of the solar
rays. Sir Isaac Newton considered that the tail is a thin vapour raised by the heat
of the sun from the comet. Probably neither of these conjectures is right ; and
the nature, uses, and laws of comets are left for future discovery.
THE EARTH,
Having described the solar system, and the planets which compose it, with the
exception of the Earth, we have reserved the latter, on account of its importance
to us rendering it desirable to describe it in connection with the celestial phenomena
with which it is associated.
The diameter of the Earth is 7,912 miles; its circumference at the equator
24,900 miles; and its mean distance from the sun 95,000,000 miles. The Earth
performs its revolution round the sun in 365 days 6 hours, forming our year ; and
turns upon its axis in about 24 hours, producing the phenomena of day and nigh*.
The ancients considered that the Earth was a large flat plain, surrounded by
water ; but what there was beyond this mass of land and water, or what there was
below it, or how the Earth was supported, were problems they were unable to solve.
At length men became more enquiring, and it was discovered that the earth is
globular, or round ; but it has been only within the last th-ree hundred years that
the true figure of the earth has been ascertained.
THE ATMOSPHERE.
The earth is surrounded on all sides by the atmosphere, which extends to the
height of about forty-five miles, decreasing in density in proportion to the altitude.
Among its important properties, it possesses that of REFRACTION ; that is, a ray
of light from any celestial object, in passing through the atmosphere becomes re-
fracted, or bent out of a straight line, and is deflected towards the earth. This
occurs to the greatest extent when the celestial object is near the horizon ; and, as
a consequence, it appears to us higher than it really is, because we see all things in
the direction in which their rays last approach the eye. It is owing to this that
the sun is seen some minutes before it rises above the horizon and after it has
sunk below it.
DAY AND NIGHT
In order that this phenomena may be clearly understood, it must be borne in
mind, first, that the earth is round ; secondly, that it receives its light from the
sun ; thirdly, that a globe cannot be illuminatejd on both sides at the same time by
one luminary ; fourthly, that if both sides are to enjoy the light, it must be in suc-
cession ; thus, while one sidi is enlightened, the other side must be in darkness
and vice versa. Now, the earth has always one side dark and the other side light ' T
and that both sides may enjoy the cheering rays of the sun, the earth is constantly
revolving upon its axis, thus bringing every part of its surface, once in every
twenty-four hours, under the influence of the meridian sunlight, and once into the
position immediately opposite. Accordingly, while it is mid- day in England, it is
mid-night on the opposite side of the globe, or in New Zealand.
THE SEASONS
The grand cause of the seasons is the inclination of the axis of the earth to the
plane of its orbit, during the revolution of the globe round the sun. This inclina-
tion is to the extent of 23^ degrees, and is always preserved ; the north pole of the
earth being constantly directed to the same point in the heavens. In consequence
of this, the north and south poles of the earth are alternately presented to the in-
fluence of the sun's light and heat ; so that, when it is summer in the northern
hemisphere, it is v* inter in the southern, and vice versa. We will briefly follow the
earth's progress in its orbit during the different seasons.
On the 20th March the sun is vertical on the equator, his rays fall equally on
the northern and southern hemispheres, and the days and nights are equal in
length all over the world. This is the SPRING EQUINOX. The earth proceeds in
its orbit, gradually the north pole comes more under the influence of the sun's ray&,
which fall more and more perpendicularly ; and the length of the days exceeds
that of the nights, in proportion to the distance from the equator, until the 21=t
June, when the sun becomes vertical at the tropic of Cancer, and we reach the
SUMMER SOLSTICE. After this, the earth proceeding in its course, the north pole
gradually recedes from the sun, the days shorten, the sun's rays become more
oblique, and on the 23rd September the sun is again vertical at the equator, and
we arrive at the AUTUMNAL EQ.UINOX. The earth speeds onward, the days be-
come shorter than the nights, the sun's rays fall more and more obliquely on the
northern hemisphere until the 21st December, when we reach the WINTER SOL-
STICE. The north pole is now furthest inverted from the sun, which has become
vertical at the tropic of Capricorn. The earth hastens on its way ; our days be-
gin to lengthen ; and the sun's rays gradually increase in power. On the 20th
March the sun is again vertical on the equator, and we rejoice in the return of
spring.
THE MOON AND ITS PHASES.
Our satellite the Moon is a globe 2,160 miles in diameter, and revolves round the
earth at a distance of 240,000 miles, in 27 days 7 hours 43 minutes and 11
seconds.
When viewed through a telescope her surface appears very bright and extremely
rugged, presenting numerous mountains and deep excavations or hollows. There
are no traces of water nor of an atmosphere.
The Phases of the Moon arise from the different positions which it assumes in rela-
tion to the sun and the earth during its revolution round the latter. When the moon
is between the sun and the earth, its dark side is presented to us, and it is conse-
quently invisible ; in this position it is called the NEW MOON. Four days after the
time of new moon it has receded 45 degrees from the sun, and now a portion of its
illuminated surface is seen in the form of a crescent. After eight days it has de-
parted 90 degrees from the sun, and shows a bright semi-circular disk ; the moon
is now said to be in its FIRST QUARTER. Gradually showing more of i'S illuminated
surface, it becomes gibbous ; and about fifteen days after the time of new moon, it
stands directly opposite the sun, presenting a complete circular disk ; this is the
FULL MOON, rising when the sun sets, and shining through the whole night. Pro-
ceeding in its course, its illuminated surface gradually decreases ; approaching the
BUII it becomes a second time gibbous ; a half- moon at its LAST QUARTER ; assumes
a crescent form ; and completing its orbit, disappears ; becoming a ntw moon
again as at first.
ECLIPSES.
When an heavenly body is darkened by the shadow of another heavenly body
falling upon it, that heavenly body is said to be eclipsed.
ECLIPSE OF THE MOON. An eclipse of the moon is caused by the earth so com-
ing between the sun and moon as to prevent the sun's rays falling upon the latter;
this can only happen at the time of full moon. If the moon's orbit were parallel to
the plane of the ecliptic, we should have an eclipse of the moon every month, at the
lime of full moon, and one of the sun at the time of every new moon ; but this does
not happen because the two orbits cut or intersect each other, and the moon's orbfr
is inclined 5 degrees 8 minutes to the plane of the ecliptic. Those two places where
the intersection takes place are called the nodes ; and an eclipse can only take place
when the sun, earth, and moon, are in conjunction (or in a line; at the time when
the moon is in one of the nodes.
ECLIPSE OF THE SUN. An eclipse of the sun is caused by the moon so coming
between the sun and the earth as to prevent the rays of the former from falling on
certain portions of the latter. This occurrence can only happen at the time of new
moon, and when she is at or near one of her nodes.
There is a great difference between an eclipse of the sun and eclipses of the moon
The light which the moon' supplies is borrowed from the sun, and when she is
eclipsed it is because the earth intercepts the sun's rays, and she is in darkness ; but
when the sun is eclipsed, he is still shining in all his splendour ; so that what is
termed an eclipse of the sun, is in reality an eclipse of the earth, caused by the moon
passing over the sun's disk, and thereby preventing his rays of light falling on a por-
tion of the earth. The moon being smaller than the sun, casts a shadow which eucla
in a point ; and, therefore, solar eclipses can only be s^en by those who are withia
the shadow of the moon at the time the solar eclipse takes place.
THE TIDES
The tides are certain movements produced in the waters which in part surround
the earth, by the attraction of the sun and moon, particularly the latter, upon
them.
The waters immediately beneath the moon being attracted by her, are elevated into
a swell, or wave of high water ; at the same time, the waters on the opposite side
of the globe are also raised into a similar swell, owing to the attraction of the moon
upon the solid mass of the earth, tending to draw it away from the waters on the
opposite side. Simultaneously, also, the waters between toe tide swells are corre-
spondingly depressed, that is, it is there low water. Now, as the moon is constantly
revolving round the earth, so the waters follow her attractive influence ; and thus
we have two tides daily, at intervals of about 12^ hours.
Tides are distinguished into neap tides and spring tides ; the difference may be
thus explained : sometimes the sun and moon are acting in conjunction, at other
times in opposition. Thus, at the time of new moon and full moon, the sun and
moon are in conjunction, when their combined attraction causes the waters to be mere
elevated, and we have what are c died spring tides. Again, at the times of half-moon,
the sun and moon are in opposition, when we have but a slight elevation of the waters,
termed neap tides.
THE FIXED STARS,
Vast as the solar system we have been considering may appear, it is but a mere
point in the map of creation. When we pass from the planetary system to the
other regions of creation, we have to traverse in imagination a space so immense,
that it has hitherto baffled all the efforts of science to determine its extent. In these
remote and immeasureable spaces are placed those beautiful luminous bodies, the
Fixed Stars, each of which is equal or superior in magnitude and brilliancy to our
sun. The grandeur of the universe thus disclosed overwhelms the mind, and its
powers fail to comprehend the immensity of space, filled as it is with system after
system in apparently endless succession.
The stars are divided into classes, according to their apparent magnitude, ranging
from the first to the sixteenth ; but all after the sixth magnitude are invisible to the
naked eye. The stars have, however, no appreciable magnitude at all, remaining
mere points of light under the greatest telescopic power. They vary simply in
brightness. To facilitate reference to the heavens, the stars havr been arranged into
groups, or constellations, of which there are 35 in the northerr hemisphere, and 46
in the southern. Ursa major is the most conspicuous and well known of the northern
constellations. Ursa minor is important from including the uorth polar star. Of
the southern constellations, Orion, with the groups in his vicinity, constitute the
richest part of the visible heavens ; Canis major, an the souih-east of Orion, con-
tains the beautiful star Sirius. The constellation of the Cross, not visible in our
latitude, is important to the mariner as indicating the direction of the south pole.
Astronomers have endeavoured to ascertain the approximate distance of the fixed
stars. Professor Bessel made very carefuJ observations of a star in the constellation
of the Swan, and the result was, that although the earth is distant in July 190 mil-
lions of mil'es from the place it occupied in January, yet the difference in the angu-
lar bearing of the same star, observed at the two periods, was somewhat less tha;>
8
one-third of a second. Its distance, consequently, could not be less than sixty-two
billions, four hundred and eightly one thousand, five hundred millions of miles ; a
space which light, that flies to us in eight minutes- from the sun, would require more
than ten years to traverse.
In a number of instances, stars, whose places have been registered in the cata-
logues, have subsequently disappeared. Some stars, on the other hand, appear to
be new, as no entry of them is found in the catalogues of former observers. There
are also temporary stars, which appear, and after shining with more or less lustre
for a time, vanish. Lost, new, and temporary stars, are among the mysteries of
nature. Some astronomers suppose that these stars are subject to a periodical trans-
lation from the depths of space, moving in vast elliptical orbits, at one extremity of
which they become visible to us, and then retire from view.
Versatile stars are such as undergo periodical mutations, regularly waxing and
waning. These singular appearances are accounted for by supposing a rotating
body to have one of its hemispheres less luminous than the other, and which, being
presented to us in the course of rotation, produces the periodical changes observed.
Multiple stars are also observed ; that is, stars which appear to the naked eye to
be single objects, are found by the telescope to be compound, consisting of two or
more individuals. They appear to be suns revolving round a common centre, each
having probably its system of planets and satellites ; but which, owing to their
enormous distance from us, are crowded into a space which a grain of sand would
cover.
NEBULAE. Under tnis term are comprised a class of objects which seem to the
naked eye patches of luminous matter, but which are resolved by powerful telescopes
into clusters of stars, the individuals of which may be reckoned by thousands. Of
such clusters of stars, there are hundreds of various shapes, each constituting as
rich a firmament as that immediately around us.
The Milky Way, which stretches across the heavens, is a wonderful system of
nebulae, or stars, of which our sun is considered to form an individual member. Of
this remarkable belt, Sir William Hershel says, " when examined through powerful
telescopes, it is found to consist entirely of stars, scattered by millions, like glitter-
ing dust, on the black ground of the general heavens."
In concluding our rapid sketch of popular Astronomy we would strongly recom-
mend to all the study of this great science, tending as it does to elevate the mind
and impress it with more exalted ideas of the glorious Creator of all things. In the
sacred writings we find frequent allusions to this sublime subject. " The heavens,"
says the Psalmist, " declare the glory of God, and the firmament showeth his handy-
work." " Lift up your eyes on high, and behold, who hath created all these things
the everlasting God, the Creator of the ends of the earth, who fainteth not, neither
is weary ; there is no searching of His understanding. He bringeth out their host
by number, and calleth them all by names, by the greatness of His might, for He is
strong in power. It is He that sitteth upon the circle of the earth, and the inhabi-
tants thereof are as grasshoppers j all nations before Him are as nothing ; and they
are counted unto Him less than nothing and vanity."
We should not only study God in the revelation he has made of himself in the
Scriptures ; but we should also study him as he unfolds his glorious attributes in
the works of creation. They are both revelations of the same almighty and benevo-
lent being ; both are in perfect harmony with each other ; both display His power,
His wisdom, and His love.
NEPTUNE
THE SC
URANUS
PRINCIPAL PLANETS,
end their Mean Distance
from the Sun in
Millions of Milea.
Period of
Revolution
In Days.
Hourly
Motion,
Miles.
MINOR PLANETS
Date of Discovery, and
Discoverer.
Period
of
Revn.
Days.
88
110 000
Ceres 1801 Piazzi
1 680
VENUS 69
225
80000
Pallas 1802 Olbers
1,686
EARTH 95
365
68 000
1 592
MARS . . . 145
687
55 000
Vesta, 1807 Olbers ...
1 326
4 332
30 000
Astrea 1845 Hencke
I 511
10,759
22,000
Hebe, 1847, Hencke
1,380
URANUS 1,828
30,687
16,000
Iris, 1847, Hind
1,346
NEPTUNE .'. 2,S6'4
1 60,126
12,500
Flora, 1847, Hind .
1 193
Metis, 1848, Graham
L.347
LONDON: PUBLISHED
&NETS,
rery, and
rer
Period
of
Revn.
Days.
MINOR PLANETS,
Date of Discovery, and
Discoverer.
Period
of
Revn.
Days.
MINOR PLANETS,
Date of Discovery, and
Discoverer.
Period.
of
Revn.
Days.
sparis ....
>, Gasparig..
ind.
2,041
1,402
1,300
1,512
1,518
1,570
1,825
1,421
1,271
Fortuna, 1852 Hind.
1,395
1,364
1,388
1,817
1,554
2,037
1,359
1,581
1.311
Bellona, 1854, Luther
Amphitrite, 1854, Marth.. ..
Urania, 1854, Hind
1,689
1,491
1,350'
2,047
1,512
1,787
Massilia, 1852, Gasparis .. .
Lutetia, 1852, Goldschmidt
Calliope, 1852, Hind
sparis
Euphrosyne, 1854, Ferguson
Thalia, 1852, Hind
Themis, 1853, Gasparis....
Phocea, 1853, Chacornac..
Prosperine, 1853? Luther..
Euterpe, 1853, Hind
jasparis... ..
sparis
ther
Hind
Polyhymnia, 1854,Chacornac
A Planet, 1855, Chacornac..
I.encothea, 1855, Luther.. ..
EYNOLDS, 174, STRAND.
Thomas
Drawn aiLiEiigravedljy JohnEmalie.
^
The Earth /> ?4.91?nulcs in circumference, and 7.9WmHes in diameter at the equater. Its si/rr<'s< v , < >ntu
greaJjjj, tlie uu v////////// ttfite bed being ruJLy as great as die inruiitilitii r'Hif snrfajxofthflaruL. <
71i,' \tirn >u/i,lm ; i Jlnit >*/>//<'/>' t:\it7itls fri/in t/ie surtiiiY t>r' the Earth , whav ItismoGt dmse, t^tii
/V.v //////// v/v/.v <>///// iniiitvluiit t /n<(litii's,it /h'.w.w.v the ]hn\\T iit'iri'mctiiVi.UIustriilit'iis i>rwhuh are duni
>'/// f -r the rei'raeli\ v e/'/'eiis r't/ie atmosphere.
EFFECT OF REFRACTION
Dundas
Jaju.es Reynolds 074 Strana.lCarckl0^i84S
V
is of square miles t'f water, and 49mOKong t>r*xtjut\'i v/^'.v A v nirerii'J A'^v//y/ v/ ////'* . /// itJJititm te
/'/r ///< luvi ;<->n,thi>
O I A C R A I
/fir ttmtntti re ^
t
so ftiUt-J hecnit.te in
fhiit time tilt- .fttir.f lift
jH'tir to complete one re-
volution roiuiii the etirtti
Rut <
/V//V.v iii>on its <:.rix . it is 1110
iijitf in its or I >it roianl the
siut . It if/// require -?-/ lumrs
tifoii 0.11 in'ertttfc throuffll the
)</,//- ,/eri<>!>.'> tts.fina from
7" ^ the ti'rst point
Aries /,. the some
*. point
77ie diameter or' the
orbit i.f I'.'i >, ( '('( ', / <
miles, an:r
* o ii-nt near ^(^'.(^(^('.('tfl* miles.
Tin's enormous distance is Ira-
o versed at the rate <>.' (.>H.O(~)O
^ tni/e.v a/i hour , or I'> ?/i/7e.-
x .In ita iinniiiil revolution li>-
^ ^ ' the earth , inclined '23^ rrom ,i Inn- />er
pendiriilar to the plane at' the orhit .
\^ V- tains iinnriahh llie s phenomena or the ^< i a,\~ons.
x^
v-\ ,
A &&
>> **
EQ "'o
> -^
''//// ///////. A///
"
/I
The comparative diameter of the Sun
upon this scale will be two feet four inches.
COMPA:
SAT
JUPITER
JUPITER 89,000. SATURN 76,000.
DIAMETER OF TI
NEPTUNE 75.500. URANUS 35,OC
PHASES OF SATURN.
The planet Saturn presents various appearances to the earth, consequent upon the
relative positions of the two bodies. Thus, while the planet traverses one part of its
orbit, the southern side is presented to us, and during its passage through another
portion of its orbit, the northern side is seen. Twice in every revolution, or once
in every fifteen years, the plane of the ring intersects the ecliptic, and its edge is
then seen as a fine line across the body of the planet; at other parts of the orbit
the ring becomes more or less open as the planet recedes from, or approaches, the points
of intersection.
LONDON: PUBLISHED B?
E MAGNITUDES OF THE PLANETS.
URANUS
MTH VENUS
,V*ARS MERCURY
MILES.
EARTH 7,912. VENUS 7,800. MARS 4189. MERCURY 3,140.
PHASES OF VENUS.
Superior Conjunction.
oooo
Inferior Conjunction.
'he brilliant and beautiful planet Venus, during its annual revolution round ~ the
presents to us phases similar to those of the moon, as represented in the diagram,
ing her conjunction she is generally invisible; but after passing ner inferior con-
Stion, she appears west of the sun as a morning star; and after passing her superior
'unction, she is seen east of the sun as an evening star. Her apparent magnitude
s according to her distance from the earth, winch at her inferior conjunction is only
million miles, but at her superior conjunction 160 millions.
NOLDS, 174, STEAND.
The Phases of the
Moon ar ise from the
different positions it
assumes in relation
to the sun and the
earth, during its revo-
lution round the lat-
ter. When the Moon
is between the sun and
the earth, its dark
side is presented to
us, it is then invisible,
and is called the NEW
MOON; proceeding in
its orbit, a portion of
its illumined surface
becomes visible in the
form of a crescent;
THE
PEAS
OF THE
M001
Eclipse of the
Moon. An eclipse
of the moon is caused
by the earth coming
between the sun and
the moon, so as to
prevent the sun's rays
falling upon the latter;
this can only happen
at the 'time of full
moon, and when the
sun, earth, and moon,
are in conjunction,
at the tune when the
moon is in one of the
nodes.
ECLIPSE OF THE MOON
E(
The Tides are
caused by the attrac-
tion of the sun and
moon upon the waters
of the earth. NEAP
TIDES are occasioned
by the attraction of
the moon alone; the
waters immediately
beneath the moon
being elevated into a
swell or tide wave,
follow her attractive
influence, as she re-
volves round the
globe. The second
tide on the opposite
LONDON: PUBLISH!
0'
J[| ALP
'(i
\
O (I
GIBBOUS
MOON
then a half moon;
three quarters full ;
and, lastly, the moon
attaining a position
opposite to the sun,
its whole illumined
disk is presented to
the earth, when it is
called a FULL MOON;
Advancing onwards
hi its orbit, its illu-
mined surface is gra-
dually inverted from
the earth, until it
entirely disappears,
and the Moon hacomes
invisible, as at first.
ECLIPSE OF THE SUN
Eclipse of the Sun.
An eclipse of the sun
is caused by the
moon so coming be-
tween the sun and
earth, as to prevent
the rays of the former
from falling on cer-
tain portions of the
latter. This pheno-
menon can only hap-
pen at the time of
new moon, and when
she is at, or near,
one of her nodes.
ES
SPRVNG TIDES.
side of the globe is
caused by the moon
attracting the solid
body of the earth
away from the waters
on that side, causing
them to be elevated
into a similar swell.
Thus we have two
daily tides. SPUING
TIDES occur from the
combined influence of
the sun and moon
when they are in con-
junction, causing the
tides to be more ele-
vated.
IEYNOLD3, 174, STRAND.
COMETS, AEROLITES
THE COMET OF 1811
Comets are heavenly bodies of a luminous and nebulous appearance, which approach to a:
recede from the sun, moving in very elliptical orbits; they usually present the following pi
nomena. A faint luminous circle is first seen by the aid of good telescopes, after a short tn
a nucleus or part where the light seems more concentrated appears, the object continues
enlarge and a tail begins to form which looks as if one side of the nucleus were projected u
stream of light away from the body of the comet. This tail increases in length, so as sometii
to spread across the whole visible heaven. The comet approaches the sun, and passing roui
it is for a time lost to view, but emerges again on the other side with increased brilliancy,
phenomena of disappearance are then in the inverse order, the same as those of its appearan<
AEROLITES.
Aerolites. These are supposed to be small bodies
moving in space, and which are occasionally met with
and attracted by the earth. Their luminous appearance
is owing to their becoming ignited by the intense heat
acquired by their great velocity and the compression of
the air. The view represents a shower of Aerolites seen
in Europe in 1835.
ELLIPTICAL
Cometary Motion, it
about the sun in orbits of a
meter very greatly exceeds t
of the extremities of the fig-
form, although of various deg
comet in its orbit, varies wi 1
rapid when near that lumina
from him. At different par
passage, showing the directio
be opposite to the sun.
LOIS'JXXN: PUBLISHED
ZODIACAL LIGHT.
ENCKE'S COMET
Diagram represents three Comets of modem times. First, the celebrated COMET of 1811,
i had a tail computed to be 123 millions of miles in length, by a breadth of 15 millions;
svhich, according to the calculations of Bessel, -will not repeat its visit till the year 5194.
,EY'S COMET, whose last appearance was in 1835, has a period of about 76 years. This
b has undergone remarkable changes in appearance. In 1456 it passed near the earth, with
extending over 60' Its later appearances have been much less conspicuous. ENCKE'S
!T, is a small comet which revolves round the sun. in about 1210 days, within the orbit of
er. It has no nucleus, or tail, but resembles a globular patch of vapour, and seems to be
asing in brightness.
COMET.
en stated, that comets move
a, of which the longer dia-
1 having the sun noar one
aet moves in an orbit of this
ty. The rate of motion of a
from the sun ; inconceivably
in proportion to its distance
, a comet is indicated it its
i every part of its course, to
THE ZODIACAL LIGHT.
The Zodiacal Light is a luminous phenomenon
occasionally seen in the heavens. Its figure resembles an
inverted cone, having its base towards the sun, and its
axis lying along the zodiac. It is generally of a delicate
rose tint, and is most favourably seen early in March,
shortly before sunrise or after sunset.
HSOL.DS. 171. STKAtfP.
PICTORIAL
DESCRIPTIVE ATLAS
OP
GEOLOGY.
ILLUSTRATING THE PRINCIPLES OF THIS
IMPORTANT SCIENCE.
REVISED
BY JOHN MORRIS, F.G.S.
LONDON: JAMES REYNOLDS, 174, STRAND.
POPULAR GEOLOGY,
Geology is a branch of science which investigates both the ancient natural
history and physical condition of the earth's crust ; treats of the successive modi-
fications it has undergone; and the agencies which even now are producing
changes on the surface of the globe. Palaeontology, which specially treats of the
history and affinities of those animals and plants whose remains occur in the
various strata; and Mineralogy, which treats of the composition and actual
nature of the materials composing the various rocks and strata, are intimately
connected with geology.
The crust of the earth, up to the altitude of 24,000 feet, and down to depths of
3,000 feet, has in every direction of its accessible parts been investigated, and
sufficient is known of its structure to warrant the assumption, with tolerable
certainty, of the following important principle: The crust of tJie earth consists of
only a proportionably small number of different rocks, and these are similar to each
other at the most distant parts of the globe, as to their principal mineral characters.
Thus the various kinds of rock are distributed over the entire globe, the granites
of South America and of the most northern climates are nearly alike; while on
the other hand, plants and animals of the equator, of the temperate zones, and
of the polar circles, exhibit the most striking differences.
Heat of the Globe. The temperature of the globe is an important element
in the history of the changes which the earth has undergone. At each point of
the earth's surface there is a certain mean temperature ; but beneath the surface,
observations show that a continual augmentation of temperature proportioned
to the depth constantly occurs. It is hence concluded, that the interior parts of
the globe are incomparably hotter than the parts at the surface; must formerly
have been still hotter, and have influenced to some extent the temperature
and all the other phenomena at the surface of the earth. That the internal heat
was once greater than it now is, is evident from many facts. The deepest rocks
are such as appear evidently to have been cooled down from igneous fusion; and
the figure of the earth is such as would result from revolution on its axis, provi-
ded the whole or a large part of its mass were in a state of fluidity or viscidity.
Modern causes Of Change. Besides the changes resulting from the gradual
cooling of the mass of the earth, there are many other forces now in action
tending to produce changes in the external crust of the globe. The varying heat
received from the sun; the effect of heat and physical condition in modifying the
animal and vegetable world; the disintegrating effect of seas, rivers, springs, and
rain; the chemical and mechanical action of the atmosphere; the disruptive
forces of volcanoes and earthquakes; the sediments transported by rivers j the
formations due wholly to the labours of innumerable marine animals ; the effects
of frost, glaciers, and icebergs all tend to produce incessant change on the
earth's surface. These changes affect the geographical boundaries of land and
water, the relative levels of land and sea, and the forms, proportions, and distri-
bution of organic life.
The statement of the effects of modern causes of change.oa the earth's surface
is also applicable to former eras of the world, at least in its general features; but
they may not always have been equal in degree of action. Many sudden changes
have evidently occurred, arising from the unusual predominance of some of the
above forces.
Successive Periods Of Formation. At a certain depth below the surface
of the earth the rocks are massive, without stratification, and without fossils,
affording evidence of having been acted on by heat; but above these rocks are
others which, by being stratified, and by having fossils peculiar to themselves,
may be classified and arranged. They represent too, epochs of time, in respect
to their period of formation, although we are u-nable to measure that time by
years or centuries.
The rocks composing the earth's crust may be classified in various ^vays*
Looking merely at the formation of the rocks, we may distinguish Stratified and
IJnstratified rocks. If we consider whether remains of plants or animals have
been found in the deposits, we may distinguish Fossiliferous and Unfossili-
ferous rocks. Lastly, if we consider the agencies which have been at work in
producing the different rocks, we may distinguish them into three groups, viz.,
the Igneous, Metamorphic, and Aqueous formations. The first have been pro-
duced by the fusion of mineral matters by the action of heat ; the second, by the
action of heat in modifying previously deposited rocks; and the last have for the
most part been deposited in strata at the bottom of seas, rivers, and lakes. The
aqueous rocks have been divided into three great series, chiefly in reference to
their organic contents, viz., the Palaeozoic series, or Primary; the Mesozoic, or
Secondary; and the Cainozoic, or Tertiary. These several series, with the groups
they include, will be found stated at length on the Table of Geological Strata,
forming one of the plates of the Atlas. The Igneous, Metamorphic, and Fossili-
ferous rocks also, are described upon the several Diagrams illustrating them.
Present Aspect Of the Globe. The outlines of land and sea throughout
the globe depend principally on the disposition and groups of mountain chains,
which in every instance yet known, are certainly shown to have been raised by
mechanical agency, generally the result of igneous action. Frequently, how-
ever, this dependence of the form of the existing land upon the ranges of
mountains is disguised by the extent of comparatively plain country which
separates the mountains from the sea. In such cases, it is necessary to admit
that the general level of the sea has subsided, or that large tracts of land have
been raised gradually, or by successive movements around the mountains, which
in earlier times may have been uplifted by more violent causes.
The interior features of every country in like manner depend upon recognized
geological agencies. The unequal elevation of mountain ranges above the sea is
a phenomenon wnich will be found of great importance in geological theory. It
appears to be true, at least in Europe, that the most elevated chains of mountains
are those whose elevation was not completed until the tertiary or later epochs.
Raised in this manner by violent or gradual movements out of the sea, the dry
land has since been subjected to waste by atmospheric action. The formation of
valleys is due to the various effects of atmospheric agency; the action of running
waters; the subsidence of the crust of the earth; dislocations on the line of
the valley; or by the overwhelming force of a general flood. The forms
of hills, like the depth and direction of valleys, are in part dependent on the
presence of strata of unequal resisting power.
The land visible on the surface of the globe is not all of the same antiquity;
some regions must have been covered with trees, and traversed by animals, before
the substance of others was laid on the bed of the sea. Since life was developed
on the globe, there appears never to have been any considerable period during
which the land or sea was wholly deprived of organic beings ; but as the condition
of the globe changed, the forms of life were altered, old races perished, new
creations were awakened, the sum of animal and vegetable existence was con-
tinually augmented, and the variety of their forms and habits continually
multiplied, until man was added to the wonders of creation.
Economic Geology. As geology advances, its application to productive
industry becomes more and more valuable. The great aid aflorded by this
science to coal mining has been shown, in indicating where coal may or may not
be reasonably looked for, according to the nature of the adjacent strata. Of the
situation of metallic treasures, enough is known to show that the occurrence of
mineral veins is a circumstance depending on conditions which are more or less
ascertainable. In planning the lines of railways, canals, &c., the engineer will
often be benefited by the records of geological surveys. The careful researches
preparatory to the selection of stone for the new Houses of Parliament, afford an
example of the way in which geology may be brought to bear on the constructive
arts, as indicating the position, character, and extent of the different marbles,
limestones, clays, &c. To the agriculturalist, geology has rendered some services,
and probably may in future be appealed to for further aid. Geology is the basis
of all sound knowledge for ascertaining the position of springs and the subterra-
nean distribution of water. The rain which falls upon all soils and rocks
indifferently, runs off the clays, but sinks into the limestones, sandstones, and
other rocks, whose open joints act like so many hidden reservoirs Hence, a
knowledge of the subsequent course of these waters is of infinite importance to
the subject of drainage, the construction of wells, and to the supply of water to
towns.
(In part abridged from an able article in the National Cyclopaedia.)
ARRIERS OF THE POLAR REGIONS
The north. Polar Regions consist chiefly of primitive and. tra
tion rocks , with few secondary and, jiXLuxial and slight tert
strata Coal of the oldest formation was roicnd at MeLvUlt
-Land , and the plants of the coal formations
TZaffins Say are similar to those wfa
now flourish between the tropics.
One of the mcst remarkable volcat
Tzanes of smoTce, and/ -red, 'hat star.
M
5 ALLUVIUM
4- TERTIARY.
3 SECONDARY
2 PRIMARY
I ICNEOUSAMETAMORPHI
VOLCANIC ROCK:
t
Coral reefs are the work of organic beings which
ejcist in inappreciable numbers . They consist of
agcibuiinated. skeletons of departed, races of polypi,
composed of carbonate of Ume , cemented into
hard calcareous rode .
e^gen
OCEAN
Madagascar
" Bengal.
, action. . The. coTie emits vast vo
fa weiglrb three- ancL four tons .
jrf. Gravel
>i.Crn,, C/,n
'k.CoIite Kai Sand-rtone
7 , Limestone , Dei'onian
ft. Gneiss. (,>old and rugged outline of the naked and abrupt rocks, and the gradually tapering
s, called Aiguilles, in the Alps. The Caucasus and Himalayas present examples of the
itions of ancient disruption or subsequent weathering of the rocky mass. To this
r agency may be attributed the singular forms of some of the granite of Cornwall.
ic principal elevations of Devon and Cornwall, as the Brent Tor, Dartmoor, Exmoor,
are composed of grey coloured, coarse, and sometimes very porphyritic granite, in
h large crystals of felspar are imbedded. Specimens of this may be seen in the pave-
of London Bridge. Granite is also found hi Cumberland and Westmoreland, and in
esea. It also occurs in Scotland, and is extensively quarried near Aberdeen.
Syenitic Granite forms the chief part of the Malvern Hills, and a similar rock occurs
Barrow-on-soar, Leicestershire, where it is extensively quarried as a road stone,
ite forms the principal chains of Norway, Sweden, and Finland, portions of the Alps,
nees, and mountain chains of Bohemia, also of the Ural, Altai, and Himalaya ranges,
t occurs over extensive tracks in Africa, and South America.
anite and the allied rocks are extensively used in the arts and manufactures; some of
olossal figures in the Egyptian saloon of the British Museum, afford examples of the
yenitic granite, basalt, and other igneous rocks. The granitic rocks are a source of
icr useful material for the manufacturer, the china clay is derived from the decompo-
of the felspar, one of the materials of granite, thus producing a substance from which
ner varieties of china and porcelain are manufactured.
POKPHYRITIC GRANITE.
AIGUILLE DE DRU, Alps.
fOLDS, 174, STRAND.
rl
ti
i
It
fc
2 f * ! S
Jrilj
liill
ITS
/' ,< ~
^^ - o
| !
I
td
*2
Hi
^ CQ (Z>
i
Gftvnnry,
I ,;u 1 1 c rlmi uti , Stt-f/x.
Mmsouri , jV .i/nn-iai j/?f)
Grer Marefc tail Srntf/Wfi 550
Tern i, Italy. , 27 (\
Foyers , Srs>t/nnd . 2(^7
r,-iun.i Fall. Dalm/itia 15ft
Tendon, /'muff, JZ.'f
(Wnessp, NewYork JtW
Khiae . Lmjrfen . Stri/x. J 65
TivH!. //,?/, 50.
8. franff. *5
WalpH'aJls Jiftrr rvrr bfrn nyafdfd a/nt>nq (hf tnfsf ittlfrrstinq and foffttt/if'u/ <>/'/Jif wi
fttift //7//v f>r xnpw mf(fs. T'/t-iS ts />arf? cu//,?/ /// f/if n&ftJlcm f>/i/~f.<> of/hs ji
x/fifif t/r thr brrf rt~ a rtvtr. as r/fuses thf water to nts7i d#wn in thai partirj/iar part wi<
Suddenly hr a xtffp r,-nr t/i if sr/rrr yrnfif Srrm they aJ'f rattfd C.
S eruieio, FyrtnA
Lulea. ,S'n
.r/V/ Serio d-E Adda
tfift Tos. /'w
Powersconrt .
Montaiorency.
7^^ TVUberftn-ce. jV. Afosri
J45. Niaoarai . di/ta
12V Rnpin. H.wiala
J15 Kakahika. A* Amf
Z#(? Lidford. AW/^
Trolh^tla. .SV/-*
I 'a r ana , Parfit/i
Cataracls of the Nil o. kt/\/
and rrntsilv tin/I qTrafidsHf" V?7isn fJ>ss<' //'.
.s, RncksfcO" Peacock lriian.sn.eid.
METAMOB
The Metamorpliic Hocks generally lie over or against the igneous rocks, and exhibit raos
a schistose and stratified character, combined frequently with a highly crystalline structu
They are supposed to bear marks of an aqueous origin, subsequently influenced by the act
of heat. Another theory supposes them to be broken fragments of igneous rocks, re-arranj
into layers or beds by the action of water.
The Metamorphic Rocks are destitute of organic remains. Veins of copper and lead
have been found in these rocks, as also those of iron, silver, gold, tin, &c.
The Metamorphic Rocks are widely distributed, and form a great part of the earth's cm
they are found in Scandinavia, Northern Russia, Ireland, the Highlands of Scotland, the Al
in Brazil, India, Africa, and North America. The scenery of the districts composed oi th
rocks is frequently wild and picturesque, and the surface often sterile and unproductive, par
arising^from themature, but generally from the elevation they attain.
Gneiss consists of quartz, felspar, mica, and sometimes hornblende, arranged in distil
layers; with the latter mineral it may be termed syenitic gneiss.
Mica Slate is a foliated aggregate of mica and quartz, and sometimes contains crystals
garnet and hornblende.
In Hornblende Slate, hornblende forms the greater part of the composition. It consi
of a mixture of hornblende and felspar or quartz, and is called Metamorphic-greenstone or gre
stone slate. The metamorphic limestone of the primary period, is often white and crystalli
and furnishes some fine marbles, and contains occasionally veins of chlorite, steatite, and soi
disseminated minerals, as augite, &c.
Chlorite Slate consists chiefly of chlorite, sometimes with quartz, felspar, hornblende or mi
Metamorphic Sandstone, or Quartz Rock is granular, and occasionally occurs as vei
in the other rocks.
Clay Slate is a slaty rock of extremely fine ingredients, containing the elements of t
other rocks in a very comminated state, subsequently altered.
Talcose Slate is a soft, unctuous, and fissile rock, containing
talc as an ingredient, generally associated, with quartz.
Actyiiolite Slate or Schist is slaty rock, formed chiefly of
actynolite, with some felspar, quartz or mica.
Serpentine, although classed with the igneous rocks, may also
be considered as belonging to this series.
The Metamorphic Rocks in the above list may be divided into two SL.
LONDON: PUBLISHED B
1C ROCKS.
iries, those which are rudely stratified, laminated, foliated or slaty, as gneiss, mica slate, clay slate ;
id those which areunstratified, as quartz rock, and the perfectly crystalline limestones or marbles
Metamorphism, or the changes the various strata have undergone, may have arisen from the
Tects of heat, heated vapours, gaseous exhalations, or the proximity of igneous rocks ; and
lese changes may have been different, according to the localities. Thus, in some places,
lere may be simply a re-arrangement, or alteration of the mineral substance, as the conver-
on of an earthy into a crystalline substance; others may have undergone an entire change,
r even loss of a portion of their substance; a third change may have effected the introduction
r elimination of minerals in some localities, which are not generally found in others; and a
mrth change may entirely alter, or even obliterate the original character, and produce a new
:ructure in the rock, as in slaty cleavage.
Although many of the Metamorphic Rocks are merely the altered palaeozoic strata, and con-
jquently referred to the primary series, still there are others of a considerable later date,
'or as igneous action has been in operation during every period of the earth's history, so it is
robable that different strata have been successively changed. Thus, some of the limestones
r finer marbles of the south of Europe, as that of Carrara and other localities, which were
>rmerly considered to belong to the primary series, are now ascertained to be of the age of
ic Jurassic rocks. The calcareous and argillaceous strata belonging to the lias, in the western
[lands of Scotland, (Portree, for example) have been converted into highly compact limestones
id a species of lydian stone. The basaltic rocks and dykes which form so prominent a feature
n the north coast of Ireland, have effected a change in the earthy chalk of that vicinity, (as
i the Island of Raghlin), with which they are in contact, converting it into compact, and
Dmetimes granular limestone.
The ordinary roofing slates belonging to the clay-slate group, are the result of metamorphic
ption. These argillaceous strata were originally deposited as fine sediment at the bottom
f the sea, and have been subsequently elevated from their original position, consolidated and
contorted; and have been also subjected to the operation of other
forces, which have produced a peculiar structure or slaty cleavage,
which cleavage is very uniform over large areas, and generally
obliterates the original planes of stratification, and rarely coincides
with them. In the accompanying figure, the undulating lines
are the planes of bedding, and the oblique lines are those of slaty
AGE. cleavage.
IEYNOLDS, 174, STRAND.
PAUEOZOIC OR PEIMARY.
^im
<:
FOSSILIFEROUS OR
The various strata composing the stratified or fossiliferous rocks, although frequeni
presenting the same mineral character, have a definite and constant order and arrangeme
which is never inverted. Thus, a group of strata in England, characterized by a certain set
fossil remains and overlying another group containing a different set of fossils, are never fou
in other countries to underlie the latter; the position of strata in relation to each other i
therefore uniform and invariable, and upon this uniformity depends the practical and ecoi
mical bearings of Geology.
The sedimentary rocks are those which include the remains of animals and vegetables, m<
or less abundantly, and are hence termed the fossiliferous rocks. They are generally eitl
arenaceous argillaceous or calcareous deposits, which owe their origin to the agency of wat
being formed within the bed of the sea, or at the bottom of freshwater streams or lakes,
indicated by the nature of the contained remains ; with which also are sometimes associal
land plants, showing that a terrestrial surface existed at different periods, and from I
destruction of a portion of which, the sandy and clayey beds were probably derived.
The stratified rocks are for convenience divided into three great series, according to th
relative antiquity, and the fossil remains found in them, which materially differ and are read
distinguished from each other; and they present three great life periods, to which the ten
primary, or palaeozoic; secondary, or mesozoic; and tertiary, or cainozoic, have been appliec
PALAEOZOIC, OR PRIMARY SERIES.
The primary series, overlying the metamorphic rocks, constitute with them some of
most elevated and picturesque scenery of the British Isles, as in Cornwall, North and Soi
Wales, the district of the Lakes, Scotland, and a large part of Ireland. From the frequ
association of igneous rocks with some of them, they have undergone considerable change i
induration, and are in this respect allied to the metamorphic rocks in fact, the orclin:
roofing slates so extensively quarried near Bangor, and previously alluded to, form a mem
of this series. Like the metamorphic rocks also, they contain many valuable deposits
mineral wealth. Fine marbles are obtained from this series; and the durable magnesian Lii
stone used in constructing the Houses of Parliament, belongs to the permian group. Besi
the valuable substance, coal, the carboniferous group contains rich deposits of iron ore and 1(
The Cambrian Rocks include a considerable thickness of schists, sandstones, and c
glomerates, as the Harlech grits, and the Llanberis and Longmynd strata. They are nef
unfossiliferous, only a faint trace of organic remains having been detected in them in Irel
Some geologists include an upper and more fossiliferous series, as the Lingula and Trema
beds of North Wales, which are considered by others to form the lower zone of .the next grc
The Lower Silurian group, including the upper beds just mentioned, and the Cara
sandstones and Llandeilo flags of Wales, constitute a series containing many fossils. T
have been traced in Wales, 'Cumberland, Scotland, Ireland, France, Spain, Germany, Russia,
The Upper Silurian group were first described by Sir R. Murchison, and include the
stones, Lucllow group, and Wenlock and Woolhope strata, and are marked by a gre
develo pmentof limestone, containing a large series of fossils.
The Devonian, or Old Red Sandstone, presents two aspects, one that of Scotland and
border counties of Wales, consisting of coarse conglomerates, sandstones, and impure li
stones, locally called cornstones, and containiug many peculiar fishes; the other, tha
LONDON: PUBLISHEE
CAINOZOIC OR TERTIARY.
OZOIC OR SECONDARY.
3IMENTARY EOCKS.
ivonshire, with a greater development of limestones, (ornamental marbles, &c.) and con-
ning many species of corals, shells, and some trilobites.
rhe Carboniferous group, so called from being the depository of the important substance,
il. A limestone shale usually interposes between the carboniferous limestone and the old
I san Istqne. Next above is a deposit of hard, coarse sandstone, called millstone grit; and
Dve this occurs an important series of sands and shales, called coal measures, and which
terstratified with them,) contain the valuable mineral, coal. They are widely distributed in
> British Isles, Belgium, Germany, France, Spain, America, Asia, &c.
Ilie Permian group, or upper member of the primary series, includes sandstones, marl
te, gypseous beds, and magnesian limestones, some of the latter are durable building stones.
Germany, this group contains a thin band of copper slate, from which copper is obtained.
MESOZOIC, OR SECONDARY SERIES.
rhe secondary series comprise a set of alternating strata of sand, clay, and earthy lime-
>nes, generally less indurated than those of the primary series. In an economical point of
;w, they are not less important; the rich deposits of rock-salt and beds of gypsum, as well
some good sandstones, belong to the triassic or lower portion of this series. From some of
3 lias clays alum is made, and jet is obtained; the finer oolitic limestones are extensively
>rked near Cheltenham, Bath, and in the Isle of Portland; the Purbeck and Wealden strata
jld some marbles which were largely used in many of the earlier churches and other edifices,
le cretaceous group is valuable for the lime, beds of flint, firestone, fuller's earth, &c.; while
ue portions of the lower chalk yield abundance of phosphatic nodules, useful in agriculture.
The Lower Secondary or Triassic group, includes the variegated sandstone, muschel-
1k, (wanting in England,) and the upper new red sandstone or variegated marl The latter
ntains gypsum (plaster of Paris) and large deposits of rock salt.
The Middle Secondary comprises the liassic group; the oolitic or Jurassic group, which
sub-divided into three parts ; and the purbeck and wealden groups.
The Upper Secondary or Cretaceous group, includes the lower green-sand, gault, upper
een-sand, and the chalk strata.
CAINOZOIC, OR TERTIARY SERIES.
The tertiary series are not so economically important. Cement stones are obtained' from
e London clay, which is also used for the manufacture of tiles ; bricks are chiefly made from
e clay and loam beds of the upper part of this series, and which generally occur along the
esent river courses, and frequently contain remains of extinct mammalia, associated with
ing fresh-water and land shells. Some portions of the crag deposits in Suffolk are exten-
rely worked for argillaceous nodules, highly impregnated with phosphatic matter, and which
ter undergoing a certain process, form a highly valuable manure.
The Lower Tertiary or Eocene, includes the Thanet sand, Woolwich beds, and the
mdon clay, the beds of the Paris basin, and also of Belgium, the Bracklesham and Barton
rata of Sussex and Hampshire, and the fluvio-marine beds of the Isle of Wight.
The Middle Tertiary or Miocene, includes the upper molasse of Switzerland, the brown
>al deposits of Germany, &c., the faluns of Touraine, the beds near Bordeaux, &c. in France.
The Upper Tertiary Or Pliocene, comprises the coralline or red crag, sub-appenine beds,
ift, also the alluvial and diluvial deposits, the fresh- water beds, and the gravel deposits.
REYNOLDS, 174, STRAND.
1
i
1
TABLE OF GEO]
ORDEK OP SITPEKPOSITION AND MINERAL 01
WITH THEIR MEAN THICKNESS, AND SOME
GROUPS.
STRATA.
MINERAL (
PLEISTOCENE.
gN. PLIOCENE.
o 3 O. PLIOCENE.
o
MIOCENE.
o 5 EOCENE.
'A -4
31 :
H
Modern Deposits
River Deltas, Raised Beaches, Peat Be
A ferruginous shelly Sand, with beds (
Beds of ferruginous Sand and Gravel,
White calcareous Sand, with Shells an
The leaf beds of the Isle of Mull proba
A series of strata of Sands, calcareous
Yellow and white Sand, dark Clay wit
Yellow ferruginous Sands, and Sandst<
Dark blue or brow^i Clay, and beds of
Clays of variegated colours, as red, gr<
Mammaliferous or Norwich Crag.
Red Crag ....
Coralline Crag
(Wanting in England)
Fluvio-Marine Beds
Barton Clays
Bagshot and Bracklesham Sands-
London Clay and Bognor Beds ...
Plastic and Mottled Clays
CRETACEOUS.
>
>
>
WEALDEN.
jjf PURBECK.
3 UPPER OOLITE.
^ MIDDLE OOLITE.
I "
o >
02 LOWER OOLITE.
M
O
O
1 :
3 "
LIAS.
n
>
n
TRIASSIC.
Upper Chalk
Lower Chalk . ..
Soft Chalk (an earthy carbonate of Li
Chalk of a harder nature, and of a less
Grey Chalk, soft and very argillaceous
A silicious or calcareous Sand, with gr
Blue marly Clay, sometimes tenacious
A mass of green or ferruginous Sands,
Strong Clay of a blue or brown colour
White, yellowish and ferruginous Sane
Sandstones, argillaceous Shales, and b
Limestone, oolitic and shelly, coarse, i
Dark blue or black slaty Clay, with bi
Sands, with beds and nodules of calcai
Coarse, shelly, rubbly, and oolitic Lira
Sands, with beds and nodules of calcai
Dark blue Clay, sometimes slaty and 1
A bed of ferruginous, coarse, sandy Li
Coarse, shelly, rubbly Limestone, thin
Coarse, shelly, oolitic Limestone, Sand
A greyish tenaceous Clay, sometimes
Oolitic Limestone and Freestone, uppe
Oolitic, silicious Limestone, very fissil<
Marls and Clays, containing the argill
Coarse, shelly, calcareous Ragstone, w
Dark blue coloured Clay, laminated si
Calcareous, sandy, and ferruginous be<
Dark inter-laminations of Clays and S
A series of laminated argillaceous blue
A series of beds of dark purple slaty ft
Variegated greenish, blue, and white I
(Marls, enclosing laminated Sandstone
Red and white Sandstone, mostly fine
Chalk Marl
Gault
Lower Greensand
Weald Clay
Hastings Sands . .. . ...
Purbeck Beds
Kimmeridge Clay
Upper Calcareous Grit
Coralline Oolite
Lower Calcareous Grit ....
Oxford Clay .
Forest Marble
Bradford Clay
Great Oolite .
Stonesfield Slate
Fullers' Earth
Inferior Oolite
Upper Lias Shale
Marlstone
Middle Lias Shale
Lias Limestone
Variegated Marls or Keuper
Muschelkalk, wanting in England
Red Sandstone or Bunter
PERMIAN.
I ::
02
^ CARBONIFEROUS.
1
.
DEVONIAN.
o >
S
o UPPER SILURIAN.
| LOWER SILURIAN.
?w "
CAMBRIAN.
Knottingley Limestone
Grey laminated Limestone, slightly m
Red, blueish and white Clays and Mai
Fawn-coloured, granular, and compact
Laminated, impure calcareous beds of
Red, grey, or yellow silicious grit, son
Beds of Coal, alternating with layers c
Pebbly, coarse and fine quartzose Grit
Compact or crystalline Limestone, tin
Argillaceous Shales, dark-coloured an
Quartzose grits and conglomerates, pa
Coloured Marls, with alternating band
Finely laminated, hard micaceous quart
Grey micaceous laminated Sandstones,
Grey nodules, stratified Limestone anc
Thin Sandstones and Shales, Limeston
Beds of dark coloured flags, mostly cal
A series of grits, slates, conglomerates
Note. The average ih
Gypseous Marls
Magnesian Limestone
Marl Slate
Lower Red Sandstone . .
Coal Measures .
Millstone Grit
Mountain Limestone
Quartzose Conglomerates ...
Cornstone and Marl
Tilestone Series
Ludlow Rocks
Llandeilo or Bala Rocks
Snowdon, Skiddaw, Bangor, and
Longmynd Rocks
LONDON: PUBLISHED I
GICAL STRATA,
IE
CTERS OP THE VARIOUS STRATIFIED ROCKS;
3E LOCALITIES WHERE THEY ARE FOUND.
TERS, THICKNESS, AND LOCALITIES WHERE FOUND.
jrged Forests. [Cavern Deposits, Mammalian beds, and the Boulder or Drift Clay.
ed Clay and Loam. 4 to 12 feet. Thorp near Norwich; Bridlington, Yorkshire.
7 Shells, and locally layers of Phosphatic Nodules. 30 feet. Near Ipswich, Sutton, Ramsholt.
arals, sometimes compact, forming thin beds of Limestone. 20 feet. Orford, Ramsholt.
? to this epoch? (The shell beds of Touraine and Bordeaux in France.)
laceous Marls, Limestones, greenish Marls, &c. 400 feet. Headon Hill, Binstead, Shalcombe.
; grains, septaria and iron Sand. 250 feet. Barton Cliffs, Hampshire.
layers of flint Pebbles, and coloured Clays and Sands. 540 feet. Bagshot Heath, Bracklesham.
-een, and other coloured Sands, nodules of Septaria. 520 feet. London, Isle of Sheppey, Bognor.
&c., and layers of coloured Sands and Pebbles. 100 ft. Heading, Blackheath, Woolwich, Alum Bay.
beds and nodules of Flints. 300 feet. Northfteet, Purfteet, Brighton, Danes Dyke, Yorkshire.
our, with few or no Flints. 350 feet. Near Cambridge, Flamborough Head, Dover Cliffs.
t. Dover; Wiltshire; near Cambridge; Surrey and Sussex.
i, sometimes compact, and with layers and nodules of Chert. 120 feet. Merstham, Isle of Wight, Sfc.
times soft, with green grains disseminated in it. 50 to 100 feet. Folkstone, Cambridge.
rs of Chert and local beds of Limestone and Fullers' Earth. 250 feet. Near Maidstone; Hythe,8fc.
[ beds of shelly Limestone called Petworth Marble, and Ironstone. 150 feet. Weald of Sussex, Sfc
ible Sandstones. Tilgate Stone, a compact grey grit. 500 feet. Hastings, Tunbridge Wells, 8fc.
ihwuter Limestones and Marbles. 150 feet. Swanage Bay, Warbarrow Bay, Sfc. Dorsetshire.
{ or compact, with layers of Chert, and subordinate beds of Sand. 150 feet. Isle of Portland.
Shale, Selenite and Septaria. 400 feet. Kimmeridge and Encombe Bays, Dorsetshire.
stone. 20 to 60 feet. Scarborough, Yorkshire ; near Oxford.
some places entirely composed of Coral. 30 feet. Farringdon, Calne, Malton, Pickering, Scarboro.
stones. 20 to 50 feet. Scarborough, Malton, Yorkshire, and Wiltshire.
i, containing Septaria and Selenite. 400 feet. Oxford, Chippenham, Scarborough, Weymouth.
very variable in quality and colour. 30 feet. Kelloway Bridge, near Chippenham, Scarborough, 8fc.
r ith layers of Clay and calcareous Sandstone. 10 feet. Malmsbury, Chippenham, Yorkshire, Sfc.
rations of fissile Limestone, and layers of blue Clay. 30 feet. Corsham, Cirencester, Sfc.
y with thin beds of brown Limestone. 10 to 20 feet. Bradford, Wilts; Tetbury, Cirencester, Sfc
y shelly, the rest sometimes sandy, and often thick bedded. 120 feet. Bradford Hill, near Bath,
Stoncsfield, Oxfordshire; Sevenhampton Common, Gloucestershire.
bstance called Fullers' Earth. 30 to 100 feet. Old-down Hill, near Bath; Box; near Stroud.
f ferruginous Sand, with concretions of sandy Limestones and Shells, 250 feet. Cotteswold Hills. [
, sandy Limestone and Shale. 50 to 200 feet. Whitby; Barrow-on- soar, Leicestershire; Lyme Regis.]
s of Ironstone. 30 to 150 feet. Staithes, Yorkshire; Dumbleton Hill, near Cheltenham, fyc.
i layers of nodules of argillaceous Limestone. ^ C Dumbleton; Batiledown, nr. CJieltenham.l
Limestone, with partings of Clay or Shale. > 60 to 400 ft. < Barrow-on-soar, Lyme Regis.
grey Limestone, and the bone bed of Bristol. ) C Lyme Regis, Bath, Bristol.
.dstone and Shales, with veins of Gypsum and Rock Salt. Warwickshire, Cheshire, Derbyshire.
r aterstone, form a middle group in Cheshire. 400 feet.)
md often impregnated with Salt. Red Conglomerate. 600 feet. Cheshire, Lancashire, Sfc.
fine grained and thin bedded. 40 feet. Knottingtey and Donca&ter, Yorkshire.
rypsum. 50 feet. Mansfield, Nottinghamshire; Manchester
in Limestone, thick bedded. 300 feet. Derbyshire, Yorkshire, Ferry Hill, Sfc.
Alliaceous or sandy nature. 60 feet. Durham.
inglomeritic, loose Sands,variegated Marls, grey micaceous Sandstone, &c. Shropshire, 8fc.
nicaceous Sandstone, Ironstone, and occasionally Limestone. 3000 feet. Northern Counties, fyc.
hales, Ironstones, thin Limestones, and sometimes beds of Coal. 600 feet. Northumberlandffyc.
L In some parts beds of Marble, veins of Lead and Calamine. 2400 feet. Derbyshire ; Bristol.
sometimes bituminous. 1000 feet. Lanarkshire, Linlithgowshire, Sfc.
nwards into a dark reddish-brown coarse grained Sandstone. Symonds Yat, Monmouthshire. ^ 5000
stone, and concretionary impure Limestone. Near Hay and Abergavenny. > to
Istones, and beds of reddish Shale. Between Ludlow and Downton Castle; Caithness, Sfc. ) 8000ft.
lies, and grey argillaceous and somewhat crystalline Limestone. 2000 feet. Ludlow, 8fc.
nd dark argillaceous Shale, with nodules of earthy Limestone. 1800 feet. Wenlock, Dudley, Sfc.
zose grits, conglomerates and Freestones. 2400 feet. May Hill, Gloucestershire; Coniston, fyc.
rtdth conglomerates, Sandstone Shale, and Schist. 1200 feet. Builth, Bala, #c.
rstratified trappean rock. 20,000 feet. Snowdon, Cader Idris; Cumberland, Sfc.
given in round numbers, subject however to considerable variation in different localities.
1 REYNOLDS. 174, STRAND.
LIMESTONE
COAL SEAMS
THE CAEBONI
The Carboniferous is the most important group connected with the industrial resources
of this and other countries. Independently of its supplying the valuable fuel coat, thli
series of strata contains other useful substances It is in this country the chief source o
the iron ores; it also yields fire-clay, millstones, marbles, and limestones, the lattei
enclosing rich deposits of lead ore. The group is commonly divided into Mountain Lime
stone, Millstone Grit, and Coal Measures, but these are subject to local variation.
The Carboniferous or Mountain Limestone, may generally be regarded as the base of th(
whole Carboniferous group. In the north of England and Scotland, however, this limestone
is not a uniform bed underlying the coal measures. In Ireland and other parts of Europe
the limestone is separated from the Devonian Rocks by shales and sandstones. The thick-
ness of the limestone of this period varies from a few feet to 2,000 feet; the rock is usually
hard, and contains in its fissures numerous crystalline minerals, and ores of lead, zinc, anc
other metals.
Above the carboniferous limestone a deposit of hard coarse sandstone supervenes, called
Millstone Grit; it often contains bands or seams of coal, but of small value.
The series of strata which constitute the Coal Measures, consists of first, the under-da^
or floor, a rough argillaceous substance, containing stems of stigmaria; secondly, the coat
which occurs in seams of from a few inches to six feet, and sometimes, though rarely, thirty
feet in thickness; thirdly, the roof or upper bed, generally consisting of slaty clay, often
containing layers of ironstone nodules. Interstratified with the shales, finely laminated
clay, micaceous sand, grit, and pebbles of other rocks, sometimes occur. The coal measures
are found in a greater or lesser extent in most European countries, also in Asia, Australia,
the United States, and other parts of America.
From its bituminous' nature and structure, coal is presumed to be of vegetable origin,
and to have been derivecfTrom numerous plants which grew on the spot where the coal
seams are now found, or they were drifted into ancient estuaries arid covered by sand and
mud. These changes must have been successively repeated over large areas, as indicated
by the number of beds of coal which occur one above the other, as well as their great
extent. The plants found in the coal measures are chiefly ferns and other cryptogams,
LONDON: PUBLISHED in
NEW RED SANDSTONE
NODULES OF CLAY IRON STONE
:ROUS GKOUP.
ome coniferae (cono-bearing), and other forms, as the lepidodendron (scaly tree), allied to
ut distinct from the living Lycopodium (club mosses).
The general features of the Coal Strata will be readily perceived by an inspection of the
Magram. The fissures or fractures, often nearly vertical, and which stretch through the
ntire mass, have probably been produced by the upheaving force which also converted the
orizontal strata into the basin shape form. These rents are called Dykes, because they
ivide the continuity of the seams or bands of coal; there are also Shifts, and still more
requently, Faults or Troubles, (see F & H) by which the seam is either raised or depressed.
L Dyke which does not disturb the continuity of the workable seams is called a hitch or
lip. Whin Dykes (w) contain basalt or other rocks of igneous origin. Thin strata of
rit or shale in the heart of a coal seam are called bands, (B). The Dykes or Faults are of
lie greatest importance, as the limited area contained between each two faults, provided
liey be impervious to water, is thus drained with greater facility.
There are several varieties of Coal, all of which appear to have been formed by the action
f certain chemical forces on wood or other vegetable matter. These varieties may for the
lost part be arranged into two groups.
1st. Anthracite, also called glance coal or stone coal, containing no bitumen, is compact
nd hard, with a high lustre.
2nd. Bituminous Coal, contains bitumen, comprising caking or pitching coal, cherry
oal, splint, eannel, or candle coal, &c.
The following is the estimated yield per annum of the European Coal Fields.
Tons.
heat Britain and Ireland 64,000,000
'russia and Germany 8,000,000
telgium 5,500,000
'ranee 4,400,000
lustria 2,500,000
talian States 90,000
The United States at the present time yield about 5,500 000 Tons.
Spain and Portugal
Russia
Other Countries....
Tons.
60,000
40,000
50,000
Total for Europe 84,640,000
REYNOLDS, 174. STRAND.
Mil
Mining is the general term applied to the exploring, working, extracting, and preparing th<
distributed, and in greater or less relative abundance. Gold is frequently met with, but only
of profit. Iron is widely dispersed, and its ores occur abundantly either in regular beds or asi
occur in large quantities; arsenic bismuth, nickel, cobalt, &c., although somewhat abundant, i
do not occur in the same uniform manner in the various strata. Thus, coal, salt, gypsum, an
of copper and lead present occasionally a bedded appearance; but the greatest number of min
more or less at right angles to the strata. These veins may be described as fissures or crevic
consolidation of the rock, and then subsequently filled with various mineral substances. The
with a metallic ore, but is occupied with crystalline (sometimes not) minerals with which the
extracting. Veins generally dip or incline from a right angle, (see diagram) and sometim
1,500 feet from the surface.
The most abundant and extensive iron ores are those of .the nodules of clay ironstone associa
found in the carboniferous limestone of some counties. Galena, or lead ore, although found ir
Northumberland, &c. where
it occurs in veins of differ-
ent kinds, and frequently
contains much silver, vary-
ing from two to eight
ounces to the ton. Gold
has been found in Cornwall,
North Wales, and in Wick-
low in Ireland. Tin is
chiefly associated with the
granitic and metamorphic
rocks of Cornwall, but is
also obtained by washing
the sands and gravel of the
same county, a process
called ' streaming', and like
that employed for obtaining
gold in auriferous districts.
The chief supply of cop-
per in England is from the
ores which occur in the
metamorphic schists, &c. of
Cornwall and Devon. In
Cornwall, the rich copper
lodes run east and west,
and when they meet with
tin lodes pass through and
sometimes heave or shift
them.
The chief objects in
mining are facility in ex-
tracting the ore, drainage,
and ventilation. The ac-
companying illustration is
a representation of a copper
mine; the shafts, of which
three are shown, form the
principal entrance to and
exit from the .mine, and
through which the ore is
brought to the surface by
means of machinery moved
by horse or steam power,
and also by which the water
is raised to the adit or
drainage level. The adit
is driven from the lowest
ground through the lodes
to the perpendicular shaft,
LONDON: PUBLISHED
NG.
mineral and metallic substances found in the earth's crust. These substances are yariously
worked in a few localities; while the ores of silver, though less common, afford a larger source
ith earthy and other substances. Of the other useful metallic ores, lead, copper, tin, and zinc,
such great demand or generally applicable as the former. The metallic and other substances
, are found in regular beds, interstratified with the rocks in which they are imbedded; veins
its occur in veins or lodes which are not parallel to the stratification, but run in a direction
ocks, which have been produced by contraction or mechanical force after the deposition and
ns is very irregular, and of more or less limited extent; the vein is rarely if ever filled entirely
mineral is associated, and which occurs sometimes in such small quantities as not to be worth
to a great depth, as in Cornwall, where some of the mines are worked upwards of 1,000 to
;he coal measures ; but iron is also extensively worked from a species of haematite, which is
ts of Corn wall,' is more abundant and characteristic of the carboniferous strata of Derbyshire,
and is the level by which
the mine is drained. The
cross cuts are passages driven
from the shafts to the lodes
for the purpose of exploring
it, and which, when favor-
able Indications of ore are
presented, are extended on
the course of the lode, and
form .levels. The levels are
three feet wide and six feet
in height, are about ten
fathoms apart from each
other in depth, and by
means of which the opera-
tions of the mine are carried
en, and the ore brought to
the principal shafts. The
portions of the veins be-
tween the levels are called
pitches. Winzes are small
shafts extending from one
level to another. The cheeks
or walls, called roof and
floor, are definite partings
which enclose the lode, or
hanging wall; and foot watt,
if the lode has considerable
inclination. The outcrop is
where the vein reaches the
surface.
SUMMARY OF THE MINERAL PRODUCE OF
THE UNITED KINGDOM IN 1854.
From the Mining Records.
Quantity.. Value.
Silver 700,000 oz. 192,500
Coal 64,661,401 tons. 14,975,000
Iron 3,069,838 9,500,000
Copper 13,042 1,229,807
Lead 64,005 1,472,115
Tin 5,763 690,000
Zinc 16,500
Other Metals 500,000
Total Value 28,575,922
IEYNOLDS, 174, STRAND.
WATER SUPPLY
Springs and Wells. It has been roughly
estimated that of the quantity of rain fall-
ing on the earth, about one-sixth is absorbed
by the soil, a similar portion is carried
away by rivers, c., and the remainder is
re-evaporated. Springs are either shallow
or deep seated, and arise from the natural
overflowing of subterranean reservoirs of
water. They are of different characters,
either pure or mineral, cold, hot, and even
boiling, being dependent on the source
from whence they come.
Wells are of two kinds, ordinary, or very
deep wells; the latter being also termed
Artesian, from their having been first used
at Artois, in France. These two sources
are well illustrated by a section of the
London basin, from the north to the south
of the Thames, and they depend entirely
on the permeable and non-permeable cha-
racter of the strata comprised within that
area. Thus the ordinary or shallow wells
around London are formed by sinking into the sand and gravel, (as shown at a a) which from
their permeable nature become more or less charged with water, which is retained therein as
in a reservoir by the retentive nature of the thick bed of London clay immediately below it.
In the other case, that of Artesian wells, the water supply is derived from an entirely
Rules for finding Springs. Mr. Swindell, in his work on Wells, mentions the following j
grass assume a brighter colour in one particular part of a field than in the remainder, or if whe
found beneath it. In summer, the gnats hover in a column and remain always at a certain he
dense vapours arise from those portions of the surface from which, owing to the existence of su
the morning and evening. The Springs to which these rules apply are only such as are near tl
but to execute such operations with a chance of success, a certain knowledge of elementary G<
DRAINAGI
^ // j~~^r*-L^iw!&ifin-sand, which outcrop at the surface at c c. The water of the celebrated Artesian well of
nelle, at Paris, is derived from these lower cretaceous strata.
;t simple rules for discovering Springs near the surface. In the early part of the year, if the
er is ploughed, if a part be darker than the rest, it may be suspected that water will be
3 the ground over the spots where springs are concealed. In all seasons of the year, more
i springs, a greater degree of humidity gives rise to more copious exhalations, especially in
i when the source is lower, they are rarely sufficient, and the only safe guide is a boring;
I of the arrangement of strata in the locality is absolutely necessary.
F LANDS.
b, it will be requisite to cut the drains through the retentive soil, and if the porous stratum
hallow, through that also. In this case, if a valley exposes as at b the outcrop of the
)us bed, the land will be more easily drained; otherwise, if a gully be cut into the porous
as at a, the drainage can be carried to lower levels. Where a tongue of porous soil lies
n a bed of clay, as shown in the third diagram, producing a swamp or morass, a main drain
through the clay at the point D, will be the proper remedy.
ig. 4. This figure may afford an illustration of unequal drainage, due to the arrangement
tie substrata; the land over a will be more effectually drained in consequence of its imme-
ely overlying the mixed porous strata, than at b, where it covers the retentive bed; either
ace furrows to connect with the part a, or by boring down to M, will render the drainage
form.
'NOLDS, 174, STRAND.
Pterodai-tjlc.
Ignanodon.
DINOSAUKIANS.
Hylaeosaurus.
Megalosaurus.
Teier
GEOLOGICAL RESTORATIO1
Tlie science of Palaeontology treats of the history of fossils, and its principal object is to make known the forms an
zoological relations of the beings which have inhabited the globe at various epochs anterior to our own. This scien<
furnishes the only certain basis for the determination of the stratified rocks, and for clearing up several essential poin
relative to the ancient limits of seas and continents. The presence of fossils of species which belong to the kinds essei
tially fluviatile, serve to indicate the existence of land and river courses; whilst fossils of marine species prove, on tl
contrary, that the strata where they are deposited have been formed either near to or far from the coasts of seas i
different epochs An inspection of the various strata hi which fossils have been deposited shows that, in general,
constant order has existed in their formation. The sea, by which the earth appears to have been covered, bavin
rested in certain situations a sufficient length of time to deposit particular strata, and to sustain the life of certai
genera and species of animals, has undergone change; the animals of each period have become extinct, and bee
successively replaced by other forms of life equally adapted to the changed conditions, whose remains are found in ea<
stratum, and are generally limited to, and characteristic of, one formation, although the mineral character may n<
always be the same.
Of the two great classes of life, the vertebrate and invertebrate, the latter are more abundant than the former; ar
the forms belonging to the sea far more numerous than those of freshwater. If we divide the three great series
stratified rocks by the forms of vertebrate life occurring in them, we shall find that Fishes characterize the primar;
Reptiles the secondary; and Mammalia the tertiary series. Of some of these we shall offer a few illustrations.
In the primary series, the prominent vertebrate forms were fishes belonging to tribes but feebly represented In 01
present seas. Two genera of reptiles only have yet been met with in them, these are the Telerpeton from tl
Devonian beds of Scotland, and the Archegosaurus from the coal measures.
The diagram is intended to illustrate the restoration! of the more remarkable forms of reptile life, whose remains a
found in those formations which constitute the secondary epoch. The illustration is partly copied from a sketch 1
Mr. Waterhouse Hawkins, F.G.S., to whose genius and industry the restorations of these animals at the Crystal Palai
are due. With the lower secondary p3riod or Trias, appeared new forms of reptilian life, -the Capitosaurus, Noth
saurus, and Labyrinthodon. For soms time impressions of foot prints only had been observed on some sandstoni
belonging to the trias of Cheshire, and to which, from their form, the term Chirothcrium was applied, iintil Professi
Owen investigated and showed that the remains of the teeth and bones found in this deposit in Warwickshire, belongt
to a reptile allied to the Batrachian order, and from the peculiar structure of its teeth it has been named tl
LABYRINTHODON, and to which the footmarks were probably due.
* Next in ascending order we have the group of Enaliosaurians or sea lizards, reptiles with back bones somewh
resembling those of fishes, and from the structure of the air passage leading to the nostrils, they must have breaths
LONDON: PUBLISHED
ENAMOSAI'RIANS.
terodacfyle.
Plesiosaiirus.
Ichthvosanrus.
Labyrinthodon.
T THE CRYSTAL PALACE.
! air like land quadrupeds, but were cold-blooded like the crocodiles and other reptiles. Of these are represented the
HTHYOSAURUSandthe PLES1OSAURUS from the Lias. The former, or fish-lizard, presents combinations of
i mammalian, reptile, and fish structure. The short neck and long tail distinguish it from the Plesiosaurus; its
go and peculiar eye endowed it with great powers of vision, and the wide mouth and long jaws armed with many
nted teeth, indicate its carnivorous and predatoiy nature. The PLESIOSAURUS, another singular form from the Lias,
:haracterized by its neck of enormous length supporting a head resembling that of the lizard, furnished with the
th of a crocodile, with a trunk and tail of an ordinary quadruped, the ribs of the chameleon, and paddles similar to
ise of the whale. The TELEOSAURUS, found also in the Lias and Oolite, was a large extinct reptile, somewhat
embling the long and slender jawed crocodile of the Ganges.
rhe PTERODACTYLES, or flying lizards, were covered by scales, and provided with wings, consisting of folds of
n, supported on the long outer finger.
'n the secondary strata, are also found another group of colossal reptiles of great magnitude and extraordinary
ucture, called the Dinosaurians; the genera of this group combined both crocodilian and lacertian characters, they
s principally marked by the peculiar construction of their sacral and dorsal vertebrae, by the articulation of the ribs,
I the modification of the teeth. Of this tribe, Professor Owen remarks, that the principal genera are the Megalo-
irus, Hylseosanrus, and Iguanodon, the gigantic crocodile-lizards of the dry land; whose peculiarities of osteological
ucture distinguish them as clearly from the living terrestrial and amphibious saurians, as the opposite modifications
an aquatic life, characterize the extinct Enaliosaurians or marine lizards. The MEGALOSAURUS occurs in the
rer oolitic strata near Oxford. The HYUtOSAURUS and IGUANODON belong to the wealden deposits; the
mcr, or weald-lizard, is marked by its extraordinary dermal covering. Of the Iguanodon, Dr. Mantell states that it
jailed in bulk the large herbivorous mammalia, and was as massive in its proportions, for living exclusively on
;etables, it must have had the abdominal region greatly developed. Its limbs must have been of proportionate size
1 strength to sustain and move so enormous a carcase; its hinder extremities prob bly resembled those of the
ipopotamus, while the fore feet appear to have been less bulky, and adapted for seizing and pulling down the foliage
J branches of trees; the remains of coniferous trees, arborescent ferns, and cyc-ideous plants, which are found
bedded with its remains, attest the nature of the flora adapted for its sustenance.
I'he mammalia are represented by the MEGATHERIUM, a colossal sloth, whose remains occur abundantly in South
nerica. This genus belonged to an extinct family of Edentata, (so named from the absence of incisor teeth) and is
resented at the present day by the diminutive sloths, anteaters, and armadilloes. The gigantic fossil IRISH ELK,
lich far exceeded in magnitude iny living deer, has been found in the shell marl underlying the peat beds of
(land, and the Isle of Man; its remains have also been obtained from some parts of England,
KYSOLDS, 171, STKAXD.
I ON
\^-.j*~jt~.J*-f2
1 8 tt 1 5 -' >5/ C^ 2 J 3'< 5 ^^
W
JT JEl JL ) J, 4^^kJU> J4L
FROM THE DISCOVERIES OF THE
THIS MAP /.v intended to cmihle th<- r\r fc i>*ra'i\-e tit a (jlanfe the iffent Physical
EU-vated and TaMo lauds by the darhw the Mountains by the darkest, the Descrls
yreata- velocity-, cind the arrows shoin/u? tin.- lUwtion <>f the current 'lit*- \\ari
-pei-atnre of the Air is shwn by the Isotherms, or */ the Arctof Current, (uul the fjiilt .
& WttRU)
MINENT MODERN GEOGRAPHERS.
ft<; Surface of' the globe-. In the Continents, thf Lowlauds orz/, <&e
w//. In the (><(< in ,the Currents arc .ftu-n-n b\ fine tines .the deeper shading iruiu-atiiuj the
aters /.- .vhwn b\ figures indicating the degree, of Fahrenheit at those spots . The tern
m,ji ,-uil the ilearet- of' Fahrenheit, all pUnes situated on, these lines having the, sajne.
the (fti-dt nit Inencf />/ those currents upon ihe cltmate of the nayhbourinfl (Countries.
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P H E
SHOWING THE INFLUENCE EXERTED BY THE HEA'
V _/'*H
^g^lil
V?3siNfo
7 jBourbon . Indian Ocean . \ 12 lianbora . Jia I
8 Peshan, Taatcay . B Mahave,
Sinqallanq , Sumatra . 14
JO f eadi . The small figures near
the coast denote the rise
l SufiL: en the
\P OF
DEPTH OF THE OCEAN
The tightest shading aver
the Ocean, indicates
depth under 5O fathoms,
qreater depths are shown
try contour lines and
Rain. The comparative quantity of rain ^
77t different districts is indicated by the increas
-ing depth of shading; the small futures shon r
the annual amount in indies. The rtaures nith
R.D. denote the number of rainy days in a. i'ear. Tempera! ure The mean t
of January is showily the Isothermal tines thus 36 and of Jtt2} thuj 64*?
'line A B en. the Ma
RANUNCULACEXE.
^ Fig. 1.
CROWFOOT.
NYMPHACE/E.
Fig. 4.
WATER-LILY.
RESEDACE/E.
MAGNOLIACE/E.
x/'S
ANONACEXE.
Fig. 2.
MAGNOLIP.
NELUMBIACE/E.
Fig. 3.
CUSTARD APPLE.
PAPAVERACE/E.
FLACOURTIACE/E.
Fig. 6.
POPPY.
DROSERACEXE.
Fig. 7.
WELD.
Fig. 8.
A UNOTTO.
Fig. 9.
VENUS'S FLY TRAP.
POPULAK SKETCH
OP
THE VEGETABLE KINGDOM.
SHOWING THE
CLASSIFICATION OF PLANTS ACCORDING TO THE NATURAL
SYSTEM,
WITH THEIR LOCALITIES, PROPERTIES, AND USES.
COMPILED FROM THE WORKS OF LINDLEY, BALFOUR, &c.
PHANEROGAMOUS, OR VASCULAR FLOWERING PLANTS.
EXOGENS.
The largest class in the Vegetable Kingdom. It is distinguished by the following
characteristics: 1. The Wood is exogenous, that is, increases in bulk by the addition
of new wood on the outside of the old wood, between it and the bark. 2. The Veins of
the Leaves are netted, and the leaves are joined to the stem, so that when dead they
separate readily at the joint. 3. The Flowers have their parts arranged in fours or
fives, or some multiple of those numbers. 4. The Seeds have usually two lobes, as in
the Bean, Almond, &c., rarely more, as in the Firs, but never one.
THALAMIFLOR2G,
Having Calyx and Corolla ; Petals distinct, and inserted into the thalamus;
Stamens hypogynous.
1. Rammeulacese, CROWFOOTS. Herbs, or rarely shrubs, found in cold, damp
climates. These plants are all, more or less, acrid and poisonous. Lindley enumerates
41 genera, and 1,000 species. (See Fig. 1.)
2. Dilleniaceae, DILLENIADS. Trees, shrubs, or undershrubs, found chiefly in Aus-
tralia, India, and the warm parts of America. They have astringent properties, and
some species are used for tanning purposes; others afford valuable timber. There are
26 genera, and 200 species.
3. Magnoliaceae, MAGNOLIADS. Fine trees or shrubs, abounding in North America,
and found also in South America, Australia, China, and Japan. Lindley notices 11
genera, and 65 species. These plants have, in general, a bitter tonic taste, and fragrant
flowers. Some species yield by distillation an aromatic oil, similar to the oil of anisej
and others are valuable for their timber. (Fig. 2 )
4. Anonaceae, ANONADS, or CUSTARD APPLE Family. Trees or shrubs of tropical
countries. Their properties are usually aromatic and fragrant; some species yield
edible fruits, and others a kind of pepper. The lancewood of coachaaakers is furnished"
by a plant of this order. Lindley mentions 20 genera, including 300 species. (Fig. 3.)
5. MenispermaC83B, MENISPERMADS, or MOONSEEDS. Twining shrubs, common in
tropical countries. There are, according to LinSley, 44 known genera, and 302 species.
The properties of these plants are, in general, bitter and narcotic; some are tonic and
others poisonous. Among the former is the root of Cocculus palmalus, or Columba-root,
a valuable bitter tonic; among the poisonous species is Anamirta cocculus, the fruit of
which is known as Cocculus indicus
6. Berberidaceae, BERBERIDS. Shrubs or herbaceous perennial plants, found chiefly
in the mountainous parts of the north temperate regions. Their properties are bitter
and acid. The bark and stem of the common Berberry supplies a yellow dye, and the
fruit is used as a preserve. Lindley gives 12 genera, and 100 species.
7. Caboinbacese, WATERSHIELDS. American aquatic plants, with floating peltate
leaves. Their properties are slightly astringent. Lindley notices 2 genera, and 3 species.
8. Nympliacese, WATERLILLIES. Aquatic plants, growing in quiet waters. These
plants are mostly confined to the northern hemisphere. The properties of some are
astringent and bitter, others are sedative, and some contain starch. Their flowers are
universally admired. Victoria regia, the beautiful lily of South America, is one of the
largest of known aquatics. Its odoriferous flowers are more than a foot in diameter,
and its leaves from four to six feet in diameter. Lindley notices 5 genera, and 50
species. (Fig. 4.)
9. Nelumbiaceae, WATERBEANS. Aquatic herbs, with large and beautiful flowers.
Found in quiet waters, in both temperate and tropical regions, but most abundant in
B
2 POPULAR SKETCH OF
India. Their nuts are wholesome, and the root or creeping stem is used as food in
China. 1 genus, and 3 species. (Fig. 5.)
10. Sarraceniaceae, SARRACENIADS, or SIDE-SADDLE Family. Herbaceous plants,
found in boggy places in North America and Guayana. Their uses are unknown.
2 genera, and 7 species.
11. Papaveraceae, POPPYWORTS. Herbaceous plants or shrubs, often with a milky
juice. These plants are chiefly European, but are found also in tropical America, Asia,
Australia, and at the Cape of Good Hope. Their properties are narcotic. Opium is
procured from the capsules of Papaver somniferum, and its varieties. The seeds of the
Opium Poppy yield a bland, wholesome oil, which is largely used on the Continent.
Lindley enumerates 18 known genera, and 130 species. (Fig. 6.)
12. Fumariaceae, FCMEWORTS. Herbaceous plants, with brittle stems and a
'watery juice. Found chiefly in the north temperate climates. Their properties are
bitter and diaphoretic. Lindley gives 15 genera, and 110 species.
13. Cmciferae, CRUCIFERS. Herbaceous plants, found in all parts of the world.
These plants possess in general antiscorbutic and stimulant qualities. To this order
belong many of the common culinary vegetables, as Cabbages, Cauliflower, Turnip,
Radish, Cress, &c. Lindley enumerates 173 genera, including 1,600 species.
14. Capparidaceae, CAPPARIDS. Herbs, shrubs, and sometimes trees. Found chiefly
in warm countries, and abundant in Africa. There are 28 genera, and 340 species.
These plants have stimulant and pungent qualities. Capparis spinosa furnishes capers.
15. Resedaceae, RESIDADS or WELDWORTS. Herbaceous plants, chiefly inhabiting
Europe, and the adjoining parts of Asia. There are 6 genera, and 41 species. Mesida
luteola, called Weld (Fig. 7), yields a yellow dye, and Resida odorata is the fragrant
Mignionette.
16. FlaCOUrtiaceae, BIXADS. Shrubs or small trees, chiefly natives of the warmest
parts of the East and West Indies, and Africa. Many of these plants furnish edible
fruit, some are astringent, and others purgative. The red dye, Arnotto, is obtained
from the pulp surrounding the seeds of Bixa orellano (Fig. 8). Lindley enumerates
31 genera, and 85 species.
17. Cistaceae, ROCK-ROSES. Shrubs or herbaceous plants of the southern parts of
Europe and the north of Africa. Some of the plants yield a resinous balsamic juice.
There are 7 known genera, and 185 species.
18. Violacese, VIOLET WORTS. Herbaceous plants or shrubs, natives of Europe,
Asia, and America. There are 14 genera, and 315 specks. The roots of these plants
possess emetic properties.
19. Droseraceae, SUNDEWS. Herbaceous plants of morasses and marshy places.
There are 8 known genera, and upwards of 90 species. The Droseras have an acid
taste, and some are said to be poisonous to cattle; others have dyeing properties.
Droncea muscipula, or Venus's Fly Trap, is a North American plant, having the laminae
of the leaves in two halves, each furnished with irritable hairs, which, on being
touched, cause the folding together of the divisions (Fig. 9).
20. Polygalaceae, MILKWORTS. Shrubs or herbs, sometimes twiners, found in most
parts of t|Tt world. They are generally bitter, and their roots yield a milky juice.
Snake-root and Rhatany-root, used in medicine, are obtained from plants. belonging to
this order. Lindley mentions 19 genera, and 495 species.
21. Tremandraceae, POREWORTS. Slender heath-like shrubs, natives of Australia.
There are 3 genera, with 16 species. Nothing is known of their properties.
22. Tamaricaceae, TAMARISKS. Shrubs or herbs, found in the vicinity of the
Mediterranean. Their bark is bitter and astringent, and some, when burned, yield
sulphate of soda. Lindley mentions 3 genera, including 43 species.
23. FranckeniaceaBj FRANKENIADS. Herbs or under shrubs, found chiefly in
Southern Europe and Northern Africa. They have mucilaginous and slightly aroma-
tic properties. 4 genera, 24 species.
24. ElatinaceaB, WATER-PEPPERS. Annual marsh plants, with hollow creeping
stems, found in all parts of the world. Some of them have acrid properties. There
are 6 genera, and 22 species.
25. Caryophyllaceae, SILENADS or CLOVEWORTS. Herbs, and sometimes suffruticose
plants, chiefly of temperate and cold regions. Most of these plants are weeds, but some
are admired garden flowers, as the pink, carnation, &c. Lindley mentions 53 genera,
aud 1,055 species.
26 Vivianaceaa, VIVIANADS. Herbaceous or suffruticose plants of South America,
having no properties of importance. 4 genera, 15 species.
27. Malvaceae, MALLOW-WORTS. Herbaceous plants, trees, or shrubs. Found
chiefly in tropical countries, and in the warm parts of the temperate zone. All these
plants are wholesome, and generally yield much mucilage. Some furnish materials for
MALVACEAE.
MALVACE/E.
MALVACE/E.
Fig. 10.
HERBACEOUS COTTON.
STERCULIACE/E.
Fig. 18.
THE BAOBAB.
TILIACE/E.
Fig. 11.
SEA ISLAND COTTON.
STERCULIACE/E.
Fig. 14.
MONKEY'S BREAD.
TILIACE>.
Fig. 12.
GREEN SEED COTTON.
BYTTNERIACE/E.
Fig. 15.
CHOCOLATE NCT.
TERNSTRCEMIACE/E.
Fig. 17.
JUTE.
Fig. 18.
TEA PLANT.
AURANTIACE/E.
AURANTIACE/E.
AURANTIACE/E.
Fig. 19.
CITRON.
GUTTIFERXE.
Fig. 22.
GAMBOGE PLANT.
SAPINDACE/E.
Fig. 25.
HORSE CHESTNUT.
Fig. 20.
LIME.
GUTTIFERXE.
Fig. 21..
SHADDOCK.
ACERACE/E.
Fig. 23.
MANGOSTEEN.
RHIZOBOLACE/E.
Fig. 24.
SUGAR MAPLE.
CEDRELACE/E.
Fig. 26.
S I:\VARROW Nrr.
Fig. 27.
MAHOGANY TREE.
THE VEGETABLE KINGDOM. 3
cordage, and others supply cotton, &c. Cotton is composed of the hairs surrounding
the seeds of various species of yossypium. (See Figs. 10, 11, and 12). Lindley enumerates
37 genera, including 1,000 species.
28. SterCllliacese, STERCULIADS. Trees or shrubs of warm climates. These plants
are mucilaginous and demulcent; many are used for food, and others supply a material
like cotton. Adansonia digitata, the Baobab tree of Senegal (Fig. 13), is one of the
most ancient of trees Its trunk has been found with a diameter of thirty feet, and the
age of some specimens is calculated at 5,000 years. The pulp of its fruit, called
Monkey's bread (Fig. 14), is used as an article of food. Lindley mentions 34 genera,
and 125 species.
29. Byttneriacese, BYTTNERIADS. Trees, shrubs, or undershrubs, abounding in
tropical countries. These plants are highly mucilaginous, and many supply materials
for cordage. The seeds of Theobroma Cacao, or Cacao-beans (Fig. 15), furnish the
chief ingredient in chocolate. Lindley mentions 45 genera, and 400 species.
30. Tiliaceae, LINDEN -BLOOMS. Trees or shrubs found chiefly in tropical countries
(Fig. 16). Lindley enumerates 35 genera, including 350 species. These plants possess
mucilaginous properties, and many supply excellent cordage material, as Jute. (Fig. 17.)
31. Dipterocarpaceae, DIPTERADS. Gigantic trees, abounding in resinous juice,
found in India and the East Indian Islands. There are about 8 known genera, and 48
species. A kind of camphor is yielded by Dryobalanops Camphora. Indian copal, the
Gum animi of commerce, is procured from Valeria Indica ; this tree also yields the
Butter of Canara, or Pinei Tallow.
32. Chlsenacese, CHL^NADS. Trees or shrubs found in Madagascar. Their pro-
perties are unknown. There are 4 genera, and 10 species.
33. Ternstrcemiacese, THEADS, or TEAS. Trees or shrubs abounding in South
America, India, China, and North America. There are' 33 genera, and 130 species.
The most important plants of this order are those which yield Tea. The black and
green teas of the northern districts of China are obtained from the same species,
namely, that known in Britain as the Thea viridis, while the black and green teas from
the Canton district are made from the variety known as Thea Bohea (Fig. 18).
34. Olacaceae, OLACADS. Trees or shrubs, chiefly tropical or sub-tropical. Little is
known of their properties. Balfour gives 24 genera, and 53 species.
35. Alirantiacese, CITRONWORTS. Trees or shrubs, remarkable for their beauty.
They abound in the East Indies, and are found in other warm regions. There are 20
genera, and 95 species. The plants of this order secrete a fragrant bitter and volatile
oil, and the fruit has a more or less acid pulp. The orange, lemon, citron, shaddock,
and lime belong to this order. (Figs. 19, 20, 21.)
36. HypericaceaB, TUTSANS. Herbaceous plants, shrubs, or trees. They are dis-
tributed generally over the globe, being found in elevated and low, dry and damp
situations. They yield a resinous juice having purgative properties. There are,
according to Lindley, 13 known genera, and 276 species.
37. Guttiferse, GUTTIFERS. Trees or shrubs, sometimes parasitical, and natives of
tropical regions, especially of South America. Lindley enumerates 30 genera, com-
prising 150 species. These plants yield a yellow resinous juice, which is acrid and
purgative. Gamboge, employed medicinally and as a pigment, and the Mangos-
teen, a fruit of the Spice Islands, are produced by plants of this order. (Figs. 22
and 23.)
38. Marcgraviacese, MARGRAVIADS. Trees or shrubs, sometimes climbing 1 , occurring
chiefly in the warm parts of America. Their properties are unimportant. There are
4 genera, and 26 species.
39. Hippocrateacese, HIPPOCRATEADS. Arborescent or climbing shrubs. Found
principally in South America, while a few are natives of Africa and the East Indies.
The fruit of some is edible. Lindley gives 6 genera, including 86 species.
40. Erythroxylacese, ERYTHROXYLS. Shrubs or trees, found chiefly in the West
Indies and South America. Their qualities are tonic, purgative, and narcotic; some
yield a reddish-brown dye. There are 3 genera, and 80 species.
41. Malpighiacese, MALPIGHIADS. Trees or shrubs, of tropical countries chiefly,
a great number of them being found in South America. Lindley mentions 42 genera,
comprising 555 species. Many of these plants are astringent, and some have stinging
hairs.
42. Aceraceae, MAPLES. Trees, which are confined chiefly to the temperate parts
of the globe. They yield a saccharine sap, from which sugar is sometimes manu-
factured (Fig. 24). There are three genera, and 60 species.
43. Sapindacese, SOAPWORTS. Trees or shrubs, and sometimes climbing herbaceous
plants. They are natives principally of South America and India. Lindley notices
50 genera, and 380 species. In this order are included the Horse-chesnuts (Fig. 25).
B 2
4 POPULAR SKETCH OF
Many of the plants yield edible fruits, while others are poisonous. The fruit of
Sapindus saponaria is used as a substitute for soap iu the West Indies.
44. Rhizobqlaceae, RHIZOBOLS. Large trees, of the warm forests of South America.
Some yield edible nuts, known as Suwarrow nuts (Fig. 26), from which an oil is ex-
tracted equal in quality to that of the Olive. Lindley mentions 2 genera, and 8 species.
45. MeliaceSB, MELIADS. Trees or shrubs, found chiefly in the tropical parts of
America and Asia. There are 40 known genera, and upwards of 160 species. The
plants of this order possess bitter, tonie, and astringent qualities. Oils are procured
from some species, and others yield a fragrant balsam.
46. Cedrelaceae, CEDRELADS. Trees, of the tropical parts of America and Asia.
There are 9 genera, including 25 species. The plants of this order are bitter and
fragrant. Swietenia Mahogani (Fig. 27) supplies the well-known mahogany wood; and
Chloroxylon Swietenia, satin-wood.
47. Vitaceae, VINEWORTS. Climbing shrubs, inhabiting the milder and hotter parts
of the globe, and abounding in the West Indies. There are 7 genera, and 260 species.
The fruit of these plants, when ripe, is saccharine. The Grape Vine belongs to this
order. (Fig. 28.)
48. Geraniacese, CRANESBILLS. Herbs or shrubs, distributed over various parts of
the world. The plants of this order are astringent and aromatic; some of the species,
as Geranium and Pelargonium, are remarkable for the beauty of their flowers. (Fig. 29.)
There are 4 genera, and 500 species.
49. Linacese, FLAXWORTS. Annual and perennial plants, scattered over the globe,
but -most abundant in Europe, and in the north of Africa. There are 3 genera,
including 90 species. These plants yield mucilage and fibre. Flax is procured from
the inner bark of the stalk of Linum usitatissium (Fig. 30). The seeds yield Linseed oil.
50. Balsaminaceae, BALSAMS. Succulent herbaceous plants, with watery juice and
showy flowers. They are found chiefly in the East Indies. Their properties are
unimportant. Lindley mentions 3 genera, comprising 110 species.
51. Oxalidacese, OXALIDS, or WOOD SORRELS. Herbs, undershrubs, or trees, found
in the hot and temperate parts of the globe, and abundant in North America and at
the Cape of Good Hope. There are 6 known genera, and 320 species. Some are acid
in their properties; others yield esculent roots.
52. Tropaeolacese. INDIAN CRESSES. Herbaceous trailing or twining plants, with
gay flowers. Natives of the temperate parts of America. Their fruit is used as a
cress, or pickled and used as capers. Lindley enumerates 6 genera, including 44 species.
53. PittosporaceSB, PITTOSPORADS. Trees or shrubs, found chiefly in Australia.
Many of them are resinous, and of some species the berries are edible. Lindley men-
tions 12 genera, and 78 species.
54. Brexiaceffi, BREXIADS. Trees, existing chiefly in Madagascar. Lindley
enumerates 4 genera, including 6 species.
55 Zygophyllacese, BEAN CAPERS. Herbs, shrubs, or trees, occurring in various
parts of the globe, chiefly in warm regions. Lindley mentions 7 genera, including 100
species. Some of the plants abound in a stimulant resin; others are bitter and acrid.
Guaiacum qfficinale is a ber.utiful West Indian tree, yielding the hard and heavy wood
called Lignum-vitffi. (Fig. 31.)
56. Rutacese RUEWORTS. Trees or shrubs, found chiefly in the south temperate
zone. There are 48 genera, and 400 species. These plants have a peculiar odour;
many possess anti-spasmodic properties; and others are bitter, and act as febrifuges
and tonics.
57. Xanthoxylacese, XANTHOXYLS. Trees or shrubs of the tropical parts of
America. Lindley mentions 20 genera, comprising 110 species. The plants yield an
aromatic, pungent, and volatile oil; some are diaphoretic in their properties, others
are febrifugal and tonic.
58. Simarubacese QUASSIADS. Trees or shrubs, found in the tropical regions of
America, Asia, and Africa. 10 genera, and 35 species. These plants are all intensely
bitter. Quassia is used medicinally as a tonic, and frequently by brewers as a sub-
stitute for hops.
59. Odmacese OCHNADS. Undershrubs or trees, growing in tropieal countries.
They are mostly bitter, and some of them are used as tonics. Lindley enumerates 6
genera, comprising 82 species.
60. Coriariacese CORIARIADS. Shrubs found in small numbers in the south of
Europe, South America, India, and New Zealand. Some of them are poisonous.
1 genus, 8 species.
CALYCIFLOR^E.
Calyx and Corolla present; Petals distinct; Stamens attached to the Calyx.
61. Stackhousiacese, STACKHOUSIADS. Shrubs found in Australia, without any
marked properties. 2 genera, 10 species.
VITACEXE
LINACE/E.
Fig. 28.
THE VINE.
Fig. 29.
GERANIUM
Fig. 30.
FLAX PLANT.
ZYGOPHYLLACE/E.
ANACARDIACE/E.
ANACARDIACEXE.
Fig. 31.
LIGNUM VITJB.
Fig. 32.
CASHEW NUT.
Fig. 33.
MANGO.
ANACARDIACE/E.
LEGUMINOSXE.
LEGUMINOS/E.
Fig. 34.
HOG PLUM.
Fig. 35.
SENNA PLANT.
Fig. 36.
LIQUORICE PLANT.
LEGUMINOS/E.
A
LEGUMINOS/C.
ROSACE/E.
Fig. 37.
LOGWOOD TREE.
RHIZOPHORACE/E.
Fig. 40.
MANGROVE TREE.
MYRTACE>C.
Fig. 43.
GUAVA.
Fig. 38.
INDIGO PLANT.
MYRTACE/E.
Fig. 41.
ALLSPICE.
MYRTACE/E.
Fig. 44.
MALAY API-LL.
Fig. 39.
ALMOND.
MYRTACE/E.
Fig. 42.
POMEGRANITE.
CUCURBITACE>E.
Fig. 45.
GOURDS.
THK VEGETABLE KINGDOM. 5
62. Celastraceae, SPINDLE-TREES. Small trees or shrubs found in the warm parts
of Europe, North America, and Asia; and also at the Cape of Good Hope. There are
24 genera, and 260 species. These plants have sub-acrid properties, and the seeds of
some yield a useful oil; others are considered poisonous. The bark of Enonymus
tingens furnishes a yellow dye.
63. Staphyleaceae, BLADDER-NUTS. Shrubs scattered over various parts of the
globe. Some of them are sub-acrid, and others bitter and astringent. They are culti-
vated as handsome shrubs. 3 genera, and 14 species.
64. Rhamnaceae, BUCKTHORNS. Trees or shrubs, distributed generally over the globe,
and found both in temperate and tropical regions. There are 42 genera, and 250
species. Many of these plants have active cathartic properties; some yield edible
fruit, and others are tonic and febrifugal.
65. AnacardiaceSJ, ANACARDS. Trees or shrubs with a resinous and often caustic
juice. They are found chiefly in the tropical parts of the world. There are 41 genera,
and 95 species. Many of these plants supply varnishes. Anacardium occidental fur-
nishes the edible Cashew-nut. Although a resinous principle pervades the plants of
this order, yet, in some cases, it is not developed in the fruit, which becomes eatable, as
exhibited in the Mango and the Hog-plums of the West Indies. (F ; gs. 32, 33, 34.)
66. Amyridaceae, AMTRIDS. Trees or shrubs abounding in resin, and natives of
tropical regions. Lindley mentions 22 genera, and 45 species. The plants yield a
fragrant balsamic and resinous juice, which, when dry, is often used as frankincense,
and is employed medicinally as a stimulant and expectorant,
67. Connaraceae, CONNARADS. Trees or shrubs of the tropics, and possessing febri-
fuge properties. Lindley notices 5 genera, and 41 species.
68. Leguminosse, PEA and BEAN Tribe. Herbaceous plants, shrubs, or trees. The
plants of this order are very generally distributed over the globe. The number of
known genera, according to Lindley, is 467, comprehending 6,500 species. This exten-
sive and important natural order embraces many valuable medicinal plants, as those
yielding senna, gum-arabic, catechu, &c.; important dyes, as indigo and logwood;
many valuable timber trees, as locust-tree and rosewood ; and food plants, as the bean
and pea. The properties of the order are in general wholesome, although it contains
some poisonous plants. (Figs. 35, 36, 37, 38.)
69. Moringaceae, MORINGADS. Trees of the East Indies and Arabia. Some of them
have pungent and aromatic qualities. The seeds of Moringa pieryyosperma, the horse-
radish tree, are winged, and are called Ben-nuts; from these is procured a fluid oil,
used by watchmakers, and called Oil of Ben, Lindley notices 1 genus, and 4 species.
70. Rosaceae, ROSEWORTS. Herbaceous plants, shrubs, or trees, found chiefly in
the cold and temperate climates of the northern hemisphere. There are 82 known
genera, and about 1,000 species. Many of the plants yield edible fruits, as Strawberries,
Plums, Apples, Cherries, Almonds, &c. (Fig. 39). Some are astringent, others yield
hydrocyanic acid.
71. Calycanthaceae. CALYCANTHS. Shrubs with square stems, and natives of
North America and Japan. Their flowers are aromatic, and the bark of some is used
as a carminative. The order includes 2 genera, and 6 species.
72. Lythraceae, LOOSESTRIFES. Herbs and shrubs, natives of Europe, North and
South America, and India. Lindley mentions 35 genera, and 300 species. Many of
the plants have astringent qualities, and some are used for dyeing.
73. Rhizophoraceae, MANGROVES. Trees or shrubs found on the muddy shores of
the tropics. There are 5 genera, and 20 species known. Some of these plants
have an astringent bark, which is used for dyeing black. Rhizophora Mangle, the
Mangrove-tree, forms thickets at the muddy mouths of rivers, and sends out adven-
titious roots which raise the trunk above its original level, giving the tree the appear-
ance of being supported upon stalks. The fruit is sweet and edible (Fig. 40).
74. Vochysiaceae, VOCHYADS. Trees or shrubs, inhabiting the warmer parts of
America. Their properties are imperfectly known. There are 8 genera, and 51 species.
75. Combretaceae, MYROBALANS. Trees or shrubs, natives of the tropics. Their
properties are astringent, many are used for tanning, and some for dyeing. Lindley
enumerates 22 genera, including 200 species.
76. MelastoinaceaB, MELASTOMADS. Trees, shrubs, or herbs, found chiefly in warm
climates. The plants are wholesome, and the succulent fruit of several is edible.
They possess slight astringent qualities. Lindley mentions 118 genera, including
1,200 species.
77. Alangiaceae, ALANGIADS. Trees or shrubs, found chiefly in India; some, how-
ever, are natives of America. Lindley enumerates 3 genera, including 8 species.
Some of the plants yield edible fruits, others are purgative.
78. PMladelphaceae, SYRINGAS. Shrubs, natives of the south of Europe, of North
POPULAR SKETCH OP
America, Japan, and India. They have no important properties. There are 3 genera
and 25 species.
79. Myrtaceae, MYRTLES. Trees or shrubs, natives of warm climates, but many
are found in temperate regions, while some of the genera are peculiar to Australia.
There are 77 known genera, and upwards of 1,400 species. Many of these plants
yield an aromatic volatile oil; many supply edible fruits; and others furnish astringent
and saccharine substances. The leaves of some species are used as tea in Australia.
The species of Eucalyptus constitute the gigantic gum trees of Australia, some of
which attain a height of 200 feet. (Figs. 41, 42, 43, 44.)
80. Onagraceae, EVENING PRIMROSES. Herbs or shrubs, of temperate regions
chiefly. Some yield edible fruits, and others edible roots. Many of them possess
mucilaginous properties, while a few are astringent. There are about 30 known
genera, and upwards of 450 species.
81. HalprageaceaB, MARES-TAILS. Herbs or undershrubs, often aquatic, and
found in ditches and lakes in various parts of the world. They have no properties of
importance. 8 genera, 70 species.
,, 82. Loasaceae, CHILI NETTLES. Herbaceous plants, natives of America, and dis-
tinguished for their stinging qualities. 15 genera, and 70 species.
83. Cucurbit aceae, CUCURBITS. Herbaceous plants, with succulent stems. They
are natives^ of warm climates chiefly, and abound in India. 60 genera, and about 300
species. These plants are acrid, and many of them are drastic purgatives. In some
cases, however, the fruits are eatable, as the Melon, Cucumber, Gourd, and Vegetable
Marrow. (Fig. 45.)
84. Papayaceae, PAPAYADS. Trees or shrubs, found in South America, and other
warm countries. The Papa w- tree (Fig. 46) yields an acrid milky juice, which has the
property of rendering tough meat tender; and an edible fruit. There are 11 genera,
and 29 species.
85. Belvisiaceae, BELVISIAS, or NAPOLEON-WORTS. Shrubs, of the tropical regions
of Africa chiefly. There are 2 genera, and 4 species. Some are used as astringents. '
86. Passifloraceae, PASSION-FLOWERS. Herbs or shrubs, natives chiefly of warm
climates. There are 14 known genera, and 215 species. Many of the plants yield
edible fruits; others are hitter and astringent; and some narcotic (Fig. 47).
87. Turneraceae, TURKERADS. Herbaceous or shrubby plants, natives of the West
Indies, and South America. Their properties are unimportant. Lindley notices 2
genera, including 60 species.
88. Portulacaceae, PURSLANES. Succulent shrubs or herbs found in various parts of
the world. They have few properties of importance. There are 12 genera, and 184 species.
89. ParonycMaceae, KNOTWORTS. Herbaceous or shrubby plants, found in barren
places in various parts of Europe, Asia, and North America. Their properties are
unimportant. 28 genera, 120 species.
90. CrassulaceaB, HOUSELEEKS. Herbaceous plants or shrubs, often succulent,
found in the driest situations, as on rocks, walls, &c., in various parts of the world.
25 genera, 460 species.
91. Ficoideae, FICOIDS. Herbaceous or shrubby succulent plants, found generally
in warm regions. There are 16 known genera, and 440 species. Some are used as
food; others yield soda.
92. Cactaceae, CACTUSES. Succulent shrubs, with peculiar angular or flattened
stems, and usually without leaves. They grow in hot, dry, and exposed places, and
are natives chiefly of the tropical parts of America. There are 16 genera, and about
800 species. These plants are remarkable for their succulence, for their great develop-
ment of cellular tissue, and the anomalous forms of their stems. Many yield a re-
freshing edible fruit (Fig. 48).
93. GrossalariaceaB, GOOSEBERRY and CURRANT TRIBE. Shrubs of temperate
regions, many of which yield edible fruits. 3 genera, 100 species.
94. SaxifragaceaB, SAXIFRAGES. Trees, shrubs, or herbs, of temperate climates.
There are 57 genera, and upwards of 900 s'pecies. Few of the plants are put to any use.
95. Bruniaceae, BRUNIADS. Branched heath-like shrubs, natives chiefly of the
Cape of Good Hope, with no important properties. 15 genera, 65 species.
96. Hamainelidacese, WITCH-HAZELS. Shrubs or small trees, found in various
parts of Asia, Africa, and America. The seeds of Hamamelis virginica are used as
food. 10 genera, 15 species.
97. UmbelliferaBj UMBELLIFERS. Herbaceous plants, often with hollow and fur-
rowed stems. Found chiefly in the northern hemisphere. There are 267 genera,
including 1,500 species. The properties of these plants are various. Some yield food,
others gum, resinous, and oily substances, while others are highly poisonous. The
species have been grouped into four divisions : 1. The esculent species, as the Carrot,
Parsnip, Celery, Parsley, &c. 2. Those producing milky juices, which concrete into a
PAPAYACEXE.
PASSIFLORACE/E.
CACTACEXE.
Fig. 46.
PAPAW.
Fig. 47.
PASSION FLOWER.
Fig. 48.
CACTTT-TUNA.
UM BELLI FERXE.
RUBIACEXE.
RUBIACEXE.
Fig. 49.
HEMLOCK.
Fig. 50.
PERUVIAN BARK.
Fig. 51.
COFFEE PLANT.
RUBIACEXE.
DIPSACACEXE.
COMFOSITXE.
Fig. 52.
MADDER.
Fig. 53.
TEAZEL
* V-
ERICACEAE.
SAPOTACEXE.
OLEACE/E.
Fig. 55.
RHODODENDRON.
OLEACE/E.
CONVOLVULACE/E.
Fig. 56.
GUTTA PERCHA PLANT.
GENTIANACE/E.
Fig. 59.
GENTIAN.
SOLANACE/E.
Fig. 61.
JALAP PLANT.
Fig. 62.
TOBACCO PLANT.
Fig. 57.
OHVE.
BIGNON1ACE/E
Fig. 60.
TRUMPET FLOWER.
SOLANACE/E.
Fig. 63. ,
LOVE APPLE.
SCROPHULARIACEC.
POLYGONACE/E.
LAURACE/E.
Fig. 64.
FOX-GLOVE.
LAURACE/E.
Fig. 67.
CINNAMON PLANT.
EUPHORBIACE/E.
Fig. 70.
EUPHORBIA.
Fig. 65.
BUCK WHEAT.
LAURACE/E.
Fig. 68.
CLOVE.
EUPHORBIACE/E
Fig. 66.
CAMPHOR.
MYRISTICACE/E.
EUPHORBIACE/E.
Fig. 71.
CASTOR OIL PLANT.
Fig. 72.
INDIA-RUBBER PLANT.
GRAM IN EXE.
RHIZANTH/E.
Fig. 133.
SUGAR CANE.
FILICES.
Fig. 136.
TREE FERNS.
FUNGI.
Fig. 134.
RAFFLESIA.
LYCOPODIACE/E.
Fig. 137.
CLUB Moss,
Fig. 135.
EQUISETUM.
LICHENES.
Fig. 138.
ORCHIL.
ALG/E.
Fig. 139.
MUSHROOMS.
Fig. 140.
IRISH Moss SEA-WEED
THE VEGETABLE KINGDOM. 7
fetid gum resin, aa Assafoetida, Ammoniac, Galbanura, &c. 3. Those species which
supply a carminative and aromatic oil, as Carra way- seeds, Anise, Coriander, &c.
4. The poisonous species include Hemlock, Water Dropwort, &c. (Fig. 49.)
98. Araliaceae, IVYWORTS. Trees, shrubs, or herbaceous plants, found both in
tropical and in cold regions. Lindley enumerates 21 genera, comprising 160 species.
These plants are allied to Umbelliferae, and have generally aromatic and stimulant
properties. Some species of Aralia yield an aromatic gum-resin.
99. CornaceaB, CORNELS. Trees, shrubs, or herbs, of temperate climates. The
bark of some species is used as a tonic and febrifuge; the seed of Cornus mascula has
been used as food; and the seeds of Cornus sanguinea furnish oil. 9 genera, and 40 species.
COROLLIFLOE^B.
Calyx and Corolla present; Petals united, bearing the Stamens.
100. LoranthaceaB, LORANTHS, or MISTLETOES. Shrubs, usually parasitical. Many
in the tropical regions have showy flowers, which hang from the branches of trees,
presenting a beautiful appearance. Lindley mentions 23 genera, and 412 species. The
bark is astringent.
101. Caprifoliaceae CAPRIFOILS, or HONEYSUCKLE TRIBE. Shrubs or herbs, chiefly
found in the temperate climates. There are 14 genera, and 220 species. Many of the
plants have odoriferous flowers, and some possess emetic and purgative properties.
The fruit of the common Elder is used in the manufacture of Elder Wine.
102. Kubiaceae, CINCHONADS. Trees, shrubs, or herbs. The order has been
divided into two sub -orders: 1. Cinchoneae, natives of the warm regions; and 2.
Galieas, or Stellatea, natives of colder regions. There are nearly 280 genera, and
upwards of 2,800 known species. The properties of these plant? are, in general, tonic,
febrifuge, and astringent; some, however, have emetic and purgative qualities, as
Ipecacuanha. Among the food plants of this order the most important is Coffea
arabica, the Coffee plant, a native of Arabia. The Madder of commerce, used in
dyeing, is produced by the root of Rubia tinctoria. (Figs. 50, 51, 52.)
103. Valerianaceae, VALERIAN-WORTS. Herbs of temperate climates. These
plants are strong-scented or aromatic, and some of them are employed as bitter tonics
and anti-spasmodics. There are 12 genera, and 185 species.
104. Dipsacaceae, TEAZELS. Herbs or undershrubs, found in the south of Europe,
the Levant, and at the Cape of Good Hope. Their properties are unimportant. The
heads of Dipsacus fullonum, Fuller's Teazel (Fig. 53), on account of their spiny bracts,
are used in dressing cloth. Lindley notices 6 genera, including 150 species.
105. Calyceraceae, CALYCERS. Herbaceous plants of South America. Their pro-
perties are unknown. 5 genera, 10 species.
106. Compositae, COMPOSITES. Herbs or shrubs. This is one of the largest
families in the vegetable kingdom. De Candolle's division of the order, now generally
adopted, is as follows: 1. Tubulifloree; 2. Labratiflorse; 3. Liguliflorse. The plants of
this order are variously distributed over the globe. In northern regions they are
mostly herbaceous, while in warm climates they become shrubby or even arborescent.
Their properties are more or less bitter, and sometimes astringent, acrid, and narcotic.
.In this order is comprised the following well-known plants and vegetable products-
Artichoke, Thistle, Camomile, Wormwood, Southernwood, Sunflower, Lettuce, and
Safflower. (Fig. 54.) There are 1,000 genera, and 9,500 species.
107. BrunqniaceSBj BRUNONIADS. Stemless herbaceous plants, natives of Australia.
Their properties are unknown. 1 genus, 9 species.
108. Gcodeniaseae- GOODENIADS. Herbs, found in Australia and the South Sea
Islands. Some are eaten as pot-herbs. 14 genera, and 150 species.
109. StylidiaceaB, STYLEWORTS. Non-lactescent herbs or undershrubs, natives of
marshy places in Australia. Some are also found at the southern extremity of South
America. 5 genera, and 121 species.
110. Campanulaceae, BELL-WORTS. Lactescent herbs or undershrubs, natives
chiefly of northern and temperate regions. The milky juice found in the plants of this
order has acrid properties. There are, according to Lindley, 28 genera, and 500 species.
111. Lobeliaceffi, LOBELIADS. Lactescent herbs or shrubs, found both in temperate
and warm climates. Acridity is their prevailing characteristic. Lobelia inflata,
Indian Tobacco of North America, is used medicinally as a sedative and expectorant,
the milky juice of some species of this order contains Caoutchouc. There are 27
known genera, including 375 species.
112. Gesneraceae, GESNERWORTS. Herbs or shrubs, found chiefly in the warmer
regions of America. Their properties are unimportant. There are 22 known genera,
and upwards of 120 species.
113. Ericaceae, HEATHS. Shrubs, undershrubs, or herbaceous plants, with ever-
green leaves. Th> order has been divided into 1. Ericeje, the true Heaths and
8 POPULAR SKETCH OF
Rhododendrons, with scaly conical huds; 2. Monotropese, including the true Mono-
tropas, or Fir-rapes; and Pyroleae, or the Wintergreen tribe. There are 52 genera,
and nearly 880 species. The order contains many beautiful plants, which abound at
the Cape of Good Hope, and are also found in other parts of the world. The fruits of
some of these plants are eatable, as Gaultheria procumbeus, and Shallon, American
shrubs; others have poisonous narcotic properties, as many species of Rhododendron,
Azalea, &c. /See Fig. 55.)
114. VacciniaceSB, CRANBERRIES. Shrubby plants, closely allied to Ericaceae. They
are natives of temperate regions, and same of them are marsh plants. Some are
astringent, others yield sub-acid edible fruits. There are 15 genera, and 200 species.
115. Epacridaceae, EPACRIDS. Shrubs or small trees, allied to Ericaceae, and occu-
pying the place of heaths in Australia. Their flowers are beautiful, and some yield
edible fruits. 30 known genera, 320 species.
116. Columelliacese, COLUMELLIADS. Evergreen shrubs or trees, natives of Mexico
and Peru. Properties unknown. 1 genus, 3 species.
117. Styracaceae, STORAX- WORTS. Trees or shrubs, natives chiefly of warm climates.
Lindley mentions 6 genera, and 115 species. These plants are in general stimulant,
aromatic, and fragrant. Some of them yield balsamic resinous substances, as storax,
benzoin, Sec., and others dyeing material.
118. Ebenacese, EBENADS. Trees or shrubs, found chiefly in the tropical regions
and India. These plants are remarkable for the hardness and durability of their wood.
Some yield edible fruit. Lindley notices 9 genera, and 160 species.
119. Aquifoliaceae, HOLLTS. Evergreen trees, or shrubs, found in various parts of
the world. Their properties generally are astringent and tonic. The leaves and bark
of the holly are tonic and febrifuge, while its berries are emetic and purgative. Its
wood is white and hard, and is esteemed in turnery and cabinet work. Lindley
enumerates 11 genera, including 110 species.
120. Sapotaceae, SAPOTADS. Lactescent trees or shrubs, natives of the tropical
parts of India, Africa, and America. Many of the plants yield edible fruits, while
others supply oily matter. The milky juice of some of the plants contains elastic
matter, as Gutta Percha, which is obtained from Isonandra Gutta (Fig. 56). There
are 21 known genera, and 212 species.
121. MyrsinaceSB, ARDISIADS. Trees, shrubs, or undershrubs, found chiefly in the
isFands of Africa, Asia, and America. Little is known of their properties. 31 known
genera, and 325 species.
122. Jasminacese, JASMINES. Shrubs, often with twining stems, abounding chiefly
in the tropical parts of India. Their flowers yield fragrant oil, and their leaves and
roots are sometimes bitter. 5 genera, 100 species.
123. Oleacese, OLIVES. Trees or shrubs, found chiefly in temperate regions. There
are two sections of this order: 1, Olese, with a drupaceous, or berried fruit ; 2, Fraxineae,
with a samaroid, or winged fruit. Lindley notices 24 genera, including 130 species.
These plants are bitter, tonic, and astringent, and some yield oil. Olea Europcea is
the Olive-tree of the coast of the Mediterranean and south of Europe. The oil of com-
merce is obtained by expression from the fleshy pericarp of the fruit .(Fig. 57). Several
species yield a sweet exudation, called Manna, The flowering Ash is a native of the -
south of Europe, where it attains a height of twenty or thirty feet. The common Ash
(Fig. 58), attains a much greater height; its wood is tough and elastic, and is used
for oars, &c. To this order also belongs Syringa vulgaris, the common Lilac, and
Ligustrum vulgare, common Privet.
124. Asclepiadacese, ASCLEPIADS. Shrubs or herbs, with a milky juice, often
twining. Inhabitants chiefly of tropical regions, but many species extend to northern
climates. There are 141 genera, and 910 species. These plants have acrid, purgative,
emetic, and diaphoretic properties. The milky juice is generally bitter and acrid,
but sometimes it is bland, and is used as milk. The milky juice of many of the plants
contains Caoutchouc.
125. Apocynacese, DOGBANES. Trees or shrubs, usually lactescent, found chiefly
in tropical regions. Lindley enumerates 100 genera, including 566 species. Many of
the .plants are poisonous; some are used medicinally as cathartics; and a few yield
edible fruits. The juice of l^aberncemontana utilis, the Cow-tree of Demerara, is used
as milk. Many of the plants supply Caoutchouc; and some species yield a dye like Indigo^
126. Loganiacese, LOGANIADS. Shrubs, herbs, or trees of tropical and warm
climates chiefly. The order is divided into three sub-orders:!, Loganitaa; 2, Strych-
nese; 3, Spigeliese. There are about 24 known genera, and nearly 170 species. The
plants of this order are highly poisonous, and possess also narcotic properties. It
includes Strychnos Nux- Vomica, the Poison-nut, from which Strychnia is obtained.
127. Gentianacese, GENTIAN-WORTS. Herbs, and occasionally shrubs, distributed
URTICACE/E,
URTICACE/E.
URTICACE/E.
Fig. 73.
HEMP.
URTICACE/E
Fig. 76.
BLACK MULBERRY
URTICACE/E.
Fig. 77.
BREAD FRUIT.
Fig. 75.
MULBERRY.
URTICACE/E.
URTICACE/E.
Fig. 79.
BANIAX TREE
THE VEGETABLE KINGDOM. 9
generally over the globe. There are two sub-orders: 1. Gentianese; 2. Menyanthese.
The general property of these plants is bitterness, and they are used as tonics.
Lindley mentions 60 genera, including 450 species. (Fig. 59.)
128. Bignoniaceae, BIGNONIADS, or Trumpet-flower Family. Trees, shrubs, or
herbs, of tropical regions chiefly. The order has been divided' into four sub-orders:
1. Bignoniae; 2. Cyrtandrcrc; 3. Crescentieae; 4. Pedalieaa. There are upwards of
100 known genera, and about 650 species. This order comprises many showy plants;
sonae are timber trees, others furnish dyes and articles of diet, and a few have bitter
and astringent qualities. (Fig. 60 )
129. Polemoniacese, PHLOX-WORTS. Herbaceous or climbing plants, of temperate
climates generally, abounding in the north-west of America. There are 17 genera,
and 104 species. Many of these plants have showy flowers, and some are remarkable
for their development of spiral cells.
130. Hydrophyllaceaa, HYDROPHYLLS. Trees, shrubs, or herbs, of America chiefly.
Their properties are unimportant. Many have showy flowers, and some have stinging
hairs. The order has been divided into two sub-orders: 1. Hydrophylleae; 2. Diapen-
sienese. There are 18 known genera, and 77 species.
131. Convolvulaceae, BINDWEEDS. Herbs or shrubs, usually twining, sometimes
parasitical, and with a milky juice. They occur chiefly in tropical and temperate
regions. The order has been divided into two sub-orders: 1. Convolvuleae, true Bind-
weeds, leafy plants; 2. Cuscutea}, leafless parasites. There are 45 genera, and upwards
of 700 species. The roots of many of these plants possess an acrid juice, which,
having purgative properties, is used medicinally. To this order belong the Jalap
plant, Convolvulus Jalapa (Fig. 61). and the Scammony plant, Convolvulus Scammonia.
The roots of some species are used as food, as Batatas edulis, the sweet Potato.
132. CordiaceaB, SEBESTENS. Trees, natives chiefly of warm countries. Some yield
edible fruit; their bark is occasionally bitter, tonic, and astringent. There are 11
genera, and 1 80 species.
133. Boraginacese, BORAGE-WORTS. Herbs, shrubs, or trees. The order has been
divided into three sub-orders: 1. Boragineae, natives chiefly of temperate climates;
2. Ehretieae, of tropical climates; 3. Heliotropiea?, of both warm and temperate
countries. There are 67 known genera, and nearly 900 species. These plants are
generally mucilaginous and emollient. Some are astringent, others yield nitrate of
potash,
134. SolanaceSB, NIGHTSHADES. Herbs or shrubs, natives of most parts of the
world, but most abundant in the tropics. The order has been divided into two sub-
orders: 1. Rectembryse; 2. Curvembryae. There are 66 known genera, and 935 species.
These plants have, in general, narcotic properties, and some are very poisonous. In
some species, certain parts of the plant have poisonous properties, while other parts
are harmless, and are used as food. Thus Solarium tuberosum, the Potato, has slight
narcotic properties in its leaves and fruit, but in the tubers there is an abundance of
starch, and when cooked they are wholesome and nutritious. To this family belong
Belladonna, Henbane, &c., also the Tobacco plant, Nicotiana Tabacum (Fig. 62), a
native of the hotter parts of North and South America. The species of Capsicum,
supplying Cayenne pepper and Chillies, and Lycopersicum esculentum, the Tomato, or
Love Apple (Fig. 63), likewise belong to this order of plants.
135. Orobanchaceae, BROOM-RAPES. Herbaceous parasitical plants, having scales
in place of leaves. Natives of the southern parts of Europe, of Asia, North America,
and the Cape of Good Hope. Lindley mentions 12 genera, and 116 species. The
properties of these plants are, in general, astringency and bitterness.
136. ScrophulariaceSB, FIGWORTS. Herbs, undershrubs, or shrubs, generally dis-
tributed over the globe. There are 176 known genera, and 1,814 species. These plants
are acrid and slightly bitter, and some are sedative and poisonous. The most im-
portant medicinal plant of the order is Digitalis purpurea, Foxglove (Fig. 64). Some
of the species of Linaria and Calceolaria are used for dyeing.
137. Labiatae, LABIATES. Herbs or undershrubs, natives chiefly of temperate
regions. These plants are in general fragrant or aromatic, and none of them are in-
jurious. Many of them form agreeable condiments, although none are used for ordi-
nary food. Peppermint, Rosemary, Lavender, Marjoram, Mint, Sage, and Thyme,
belong to this family. Lindley mentions 125 genera, including 2,350 species.
138. Verbenacejfi, VERBENES. Trees, or shrubs, rarely herbs. The order has been
divided into three sub-orders. 1, Myoporineae, natives of South America, Africa, and
Australia; 2, Verbenae, natives of America, tropical and temperate, and found also in
Asia and Europe; 3, Selaginese, natives chiefly of the Cape of Good Hope, and found
also in Europe. There are 75 known genera, and upwards of 770 species. Many of
the plants are fragrant and aromatic; some are bitter, tonic, and astringent; and
others are acrid. The bark of Avicennia tomentosa is used in Brazil for tanning. To
10 POPULAR SKETCH OF
this order belongs Tectcna grandis, the gigantic Teak-tree of India, which attains a
height of 200 feet.
139. Acanthaceae, ACANTHADS. Herbaceous plants or shrubs, abounding in tropi-
cal regions, 'i here are, according to Lindley, 105 genera, and about 750 species.
These plants have mucilaginous and bitter qualities. The leaves of the Acanthus
gave origin to the capital of the Corinthian column.
140. Lentibulariaceae, BUTTERWORTS. Aquatic or marsh herbaceous plants,
found in all parts of the world. Lindley enumerates 4 gemra, and 173 species. These
plants have no properties of importance.
141. Primulaceae, PRIMWORTS. Herbaceous plants of temperate and cold regions.
There are 29 genera, and 215 species. Acridity prevails more or less in these plants.
They are chiefly cultivated as showy garden flowers.
142. Plumbaginaceae, LEADWORTS or SEA-PINKS. Herbs or undershrubs, in-
habiting the sea shores and salt marshes of temperate regions chiefly. Lindley enume-
rates 8 genera, and 160 species. Some of the plants are acrid, others have tonic
properties.
143. PlantaginaceaB, RIBWORTS. Herbs which are often stemless; they are found
chiefly in temperate and cool regions. Lindley notices 3 genera, and 120 species.
These plants are frequently bitter and astringent, and their mucilaginous seeds are
sometimes used as demulcents.
MONOCHLAMYDEJE.
Calyx or simple Perianth present; Corolla wanting; Flowers sometimes achlamydeous.
144. Nyctaginaceae, NYCTAGOS. Herbs, shrubs, or trees, natives principally of
warm regions. Lindley mentions 14 genera, and 100 species. Their qualities are
mostly purgative. Some species are cultivated as garden flowers.
145. AmaranthaCfcSB, AMARANTHS. Herbs and shrubs of tropical and temperate
regions. There are 38 known genera, and 282 species. These plants are mostly
mucilaginous and demulcent. Many of them are cultivated in gardens, including
those known under the popular names of Love-lies-bleeding, Cockscomb, &c.
146. Chenopodiacese, CHENOPODS. Herbs, under-shrubs, or weeds, found in most
parts of the world. There are 67 genera, and 372 species. Many of these plants are used
as esculent pot-herbs, as spinage, beet, &c. Beetroot yields a quantity of sugar, and
Ambrina anthelmintica yields a volatile oil, which is used as a vermifuge.
147. Phytolaccaceae, PHYTOLACCADS. Undershrubs or herbs, natives both of
tropical and warm countries. They are found in Asia, Africa, and America. The
order has been divided into two sub-orders: 1. Phytolacceae; 2. Petiveriea?. There are
12 genera, and about 70 species. These plants have frequently acrid qualities, and act
as irritant emetics and purgatives. Some yield potash.
148. Polygonaceae, BUCKWHEATS. Herbaceous, rarely shrubby plants, found in
most parts of the world, but especially in north temperate regions. The order has
been divided into 1. Poly goneas; 2. Eriogoneae. These plants have astringent and
acrid properties; some are purgative, and a few acrid. The fruit of Fagopyrum escu-
lentum (Fig. 65), and other species of Buckwheat, is used as food. One of the most
important plants of the order is the Rhubarb plant. Lindley notices 29 genera, and
490 species.
149. Begoniaceae, BEGONIADS. Semi -succulent herbaceous plants and undershrubs,
natives of warm countries. Their leaves and young stems are acrid, the roots are
astringent and slightly bitter. Begonia obliqua is sometimes called Wild Rhubarb.
There are 3 genera, and 159 species.
150. Lauraceae, LAURELS. Trees, and sometimes twining parasitic, and leafless
herbs, or undershrubs. Natives chiefly of the tropical regions of Asia and America.
The order has been divided into two sub-orders: 1. Lauieae, true laurels, trees with
leaves; 2. Gassy these, Dodder-laurels, climbing parasitic plants without leaves. There
are 46 genera, and 450 species. These plants are, in general, aromatic and fragrant;
many of them furnish oils, others camphor, some have bitter and tonic barks, and
others supply useful timber. Camphora officinarutn is the camphor tree of China and
Japan. Sassafras officinarum is an American tree, the root of which is used in medi-
cine. Cinnamamvm zeylanicum is the true Cinnamon tree of Ceylon. The bark of the
tree is the cinnamon of commerce; the root yields camphor. Another species, Cinna-
momum Cassia, supplies the Cassia bark of commerce. The clove nutmegs of Mada-
gasca are produced by Agathophyllum aromaticum ; and Brazilian nutmegs by Crypto-
can/a moschata. (Figs, 66, 67, 68.)
151. Myristicaceae, NUTMEGS. Trees of the tropical regions of Asia and America.
There are 5 genera, and upwards of 30 species. Acridity and aromatic fragrance are
the properties of these plants. The most important species is Myrisiica officinalis,
a tree of the Moluccas. The fruit is drupaceous, and when ripe opens by two valves,
URTICACEXE.
PIPERACEXE.
AMENTACEXE.
Fig. 80.
HOP.
AMENTACEXE.
Fig. 83.
BIRCH.
AMENTACEXE.
Fig. 81.
BLACK PEPPER PLANT.
AMENTACEXE.
Fig. 84.
PLANE.
AMENTACEXE.
Fig. 82.
WILLOW. / /
AMENTACE/E.
Fig. 85.
ALDER.
AMENTACEXE.
Fig. 88.
SPANISH CHESTNUT.
AMENTACE/E.
AMENTACE/E.
JUGLANDACE/E.
Fig. 89.
POPLAR.
CONIFERXE.
Fig. 92.
NORWAY FIR.
CONIFERS.
Fig. 90.
CORK TREE.
CONIFER/E.
Fig. 93.
SCOTCH FIR.
CONIFER/E.
Fig. 91.
WALNUT.
CON1FERXE.
Fig. 94.
SILVER FIR.
CONIFER/E.
Fig. 95.
LARCH.
Fig. 96.
TAR TREE.
Fig. 98.
WKYMOUTH PINE.
THE VEGETABLE KINGDOM. 11
displaying the beautiful scarlet arillus, which constitutes mace. Within this is a
dark-brown shell, covering the kernel, which is the nutmeg of commerce. (Fig. 69.)
152. ProteaceaB, PROTEADS. Shrubs or small trees, natives chiefly of Australia
and the Cape of Good Hope. Lindley mentions 44 genera, and 650 species. The
order has been divided into two sub-orders: 1. Nucumentaceae; 2. Follicalares. These
plants have no medicinal qualities of importance. They present great diversity of
appearance, and are cultivated for their beauty and the peculiarity of their flowers.
153. ElseagnaceaB, OLEASTERS. Trees or shrubs, found in all parts of the northern
hemisphere. Properties unimportant. The fruit of some is eaten, and Hippophaee
rhamnoides also yields a yellow dye. There ara 4 known genera, and 30 species.
154. PenseaceJfi, SARCOCOLLADS. Shrubs, found at the Cape of Good Hope, with
no properties of importance. The gum-resin, Sarcocal, is furnished by some species.
3 known genera, 21 species.
155. Thymelseaceae, DAPHNADS. Shrubby, rarely herbaceous plants. Natives of
various parts of the world, both in warm and temperate regions. There are two
sections of the order: 1. Daphneae; 2. Hemandieae. Lindley mentions 38 genera, and
SOO species. The bark of many species is acrid and irritant, the fruit narcotic. The
bark of many of the plants is made into ropes and paper.
156. AquilariaceSB, AQUILARIADS. Trees, of the tropical regions of Asia. Some
species furnish a fragrant wood called Eagle, or Aloes- wood. There are 6 genera, and
10 species.
157. Chailletiaceae, CHAILLETIADS. Trees or shrubs, of the warm parts of Africa
and South America. The fruit of some species is said to be poisonous. There are
4 known genera, and 10 species.
158. SamydaceJB, SAMYDS. Trees, natives chiefly of tropical America. Some spe-
cies of Casearia are bitter and astringent. There are 5 known genera, and 80 species.
159. Homaliacese, HOMALIADS. Trees. or shrubs of the tropics. They do not pos-
sess any important properties. Lindley mentions 8 genera, including 30 species.
160. Santalacese, SANDALWOODS. Trees, shrubs, or herbs found in Europe, Asia,
America, and Australia. There are 18 genera and 110 species. Some are astringent,
others yield fragrant wood. The seeds of some species are eaten, and the large seeds
of Pyrularia oleifera, Buffalo-tree, or Oil-nut, yield oil.
161. Aristolbclliacese, BIRTHWORTS. Herbs or shrubs, often climbing, found in
abundance in the warm regions of South America, and found also in temperate ami
cold regions of other parts of the world. These plants are generally bitter, tonic, and
stimulant, while some are acrid. The snake-roots of Canada and Virginia belong to
plants of this order. There are 8 known genera and 130 species.
162. Nepenthacese, PITCHER- PLANTS. Herbs or half-shrubby plants, natives of
swampy parts in the East Indies and China. They have no known properties.
Lindley mentions 1 genus and 6 species.
163. Datiscacese, DATISCADS. Herbaceous branched plants or trees, scattered over
North America, parts of Asia, and the south-east of Europe. Some of the plants are
bitter, and others purgative. Lindley mentions 3 genera, and 4 species.
164. Empetracese, CROWBERRIES. Heath-like shrubs of Europe and North Ame-
rica, chiefly. They have slightly acid properties. 4 genera, and 4 species.
165. EuphOfbiaceae, SPURGE- WORTS. Trees, shrubs, or herbs, often having acrid
milk. These plants abound in warm regions, especially in tropical America, where
they are found as trees or bushes, or lactescent herbs, often presepting the appearance
of Cactuses. They are also found in. North America and Europe. In Britain there
are 18 species. There are in all 192 known genera, and upwards of 2.500 species.
These plants are acrid and poisonous. In many cases, the elaborated sap contains
caoutchouc and resin. The seeds of many species yield oils, some of a bland, and
others of an irritating, nature. Castor-oil is expressed from the seeds of Recinus corn-
munis. Croton-oil is obtained from the seeds of Croton Tiglium, an Indian shrub.
Cascarilla is the bark of Croton Eleuteria, and other species. The Box-tree, Buxus
sempervirens, whose wood is used for wood- engraving, belongs to this family as does
the Cassava, or Manioc plant, the starch of which is used in the form of bread.
From the starch of the Bitter Cassava, Tapioca is prepared. The milky sap of
Siphonia elastica furnishes the bottle India-rubber. Aleurites laccifera supplies gum-
lac; and Crozophora tinctoria, a purple dye called Turnsole. (Figs. 70, 71, 72.)
166. UrticaceSB, NETTLE WORTS. Herbs, shrubs, or trees. The order has been di-
vided into five sub-orders:!. Urticeae, True Nettles; 2. Cannabinae, Hemp tribe;
3. Ulmaceae, Elm tribe; 4. Moreae, Mulberry tribe; 5. Artocarpeae, Bread-fruit tribe.
These plants are widely scattered, most of them are found in temperate climates; the
Mulberry tribe in temperate and warm regions, and the Bread-fruit tribe within the
tropics. Tiie properties of the order are various. Many yield valuable fibres, others
12 POPULAR SKETCH OF
edible fruits, others supply caoutchouc, and some form important forest trees.
Cannubis sativa furnishes the valuable fibre, Hemp. Humulus Lupulus supplies the
Hop. Several species of Elm are cultivated for timber. The common Fig is the fruit
of Ficus Carica; and many other species of Ficus yield edible fruits. The plants of
the Fig tribe are remarkable for the adventitious roots which they send out from the
stems. Ficus indica, the Banyan tree, is celebrated in this respect. Ficus elastica is
an,. Indian tree which yields a large quantity of caoutchouc, as do also some other
species of Ficus. Morus alba is the White Mulberry, the leaves of which are the
favourite fruit of silk-worms. Broussonetia papyrifera is the Paper Mulbeny,
which is used in China and Japan for making a kind of paper. The dye-wood called
Fustic is produced by Madura (Broussonetia) tinctoria. Artocarpus incisa, the Bread-
fruit tree, supplies an amylaceous fruit which affords an abundant supply of food in
tropical countries. This important order comprises between 60 and 70 known genera,
and about 600 species. (Fies. 73 to 80.)
167. Ceratophyllaceae, HORN WORTS. Aquatic herbs, found in ditches. 1 genus,
and 6 species. Properties unimportant.
168. Podostemaceae, PODOSTEMADS. Herbaceous floating plants, of South America
and some African islands. Little is known of their properties. Lindley gives 9 genera,
and 25 species.
169. Stilaginacese, ANTIDESMADS. Trees or shrubs, of the East Indies. Some
furnish edible fruits. There are 3 genera, and 20 species.
170. MonimiaceSB, MONIMIADS. Trees or shrubs, of South America and Australia.
They are fragrant and aromatic, and some yield edible fruit. 8 genera, and 40 species.
171. Atherospermaceae, PLUME NUTMEGS. Trees, of Australia and parts of
South America. Mostly fragrant. There are 3 genera, and 4 species.
172. LacistemaC633, LACISTEMADS. Shrubs or small trees, found in the warm
parts of America. Properties unknown. There are 2 genera, and 6 species.
173. ChloranthaceSB, CHLORANTHS. Herbs or undershrubs, of the warm parts of
India and America. Some are fragrant and aromatic. 3 genera, and 15 species.
174. Sauniiaceae, SAURURADS. Marsh herbs, of North America, India, and China.
They have acrid properties. There are 4 genera, and 7 species.
175. Piperacese, PEPPER-WORTS. Shrubs or herbs, natives of the hottest regions
of the globe. These plants are pungent, acrid, and aromatic; some are narcotic.
Most of them contain an acrid resin and a crystalline matter, called Piperin. The
Black- pepper plant (Fig 81) is a climbing species common in the East Indies. There
are 21 known genera, and upwards of 600 species.
176. Amentaceae, CATKIN-BEARING TRIBE. Trees or shrubs, chiefly natives of
temperate regions. The order has been divided into seven sub-orders, as follows:
1. Salicinese, the Willow Tribe, found in temperate and cold regions; 2. Myricege, the
Gule Tribe, found in North and South America, India, and at the Cape of Good Hope.
3. Casuarinese, the Beef-wood Tribe, Australian trees and shrubs ; 4. Betulineae, the
Birch tribe, natives of temperate and cold regions; 5. Balsamaceae, the Liquidambar
tribe, balsamic trees of warm regions; -6. Platanese, the Plane tribe, trees of temperate
climates; 7. Cupiliferse, the Nut tribe, natives of temperate regions chiefly. This
extensive Amental alliance embraces 18 genera, and 600 species. Some of its plants
yield resinous and balsamic fluids, and the seeds of others are used for food. Among
the timber trees of this order may be mentioned the Birch, Alder, Plane, Hazel, Oak,
Beech, Spanish Chesnut, Poplar, and the Willow. The specie sof Myrica are aromatic,
and yield resinous and oily matter. Myricia cerifera, or Wax Myrtle, yields a greenish
wax, used for candles. A resinous matter, known as Liquid Storax, is obtained from
various species of Liquidumbar ; and from the bark of the common Birch is obtained
an oil which gives the peculiar odour to Russian leather. (Figs. 82 to 90 )
177. Juglandaceae, WALNUTS. Trees, natives chiefly of North America. There
are 4 genera, and 27 species. These plants yield oily nuts, and the seeds of the
common Walnut supply a bland oil. The trees furnish a valuable timber, which is
hard, and susceptible of a high polish. (Fig. 91.)
178. Garryacese, GARRYADS. Shrubs of North America, remarkable for their
peculiar silky catkins. 2 genera, and 6 species.
179. Coniferse, CONE BEARING TRIBE. Trees or shrubs, of both hot and cold
regions. Some of the genera are peculiar to the Southern hemisphere. This extensive
order has been divided into four sub-orders, as follow:!. Abietinese, the Fir and
Spruce tribe; 2. Cupressinese, the Cypress tribe; 3. Taxineae, the Yew tribe; 4.
Gnetacese, the Joint-Fir tribe. The order comprises 31 genera, and about 165 species.
These plants furnish valuable timber, and yield various important products, as tur-
pentine, pitch, and resin. The various kinds of Pine, Fir, Spruce, and Cedar, belong
to this family. Turpentine is obtained from the Scotch Fir, and different species of
Pine. Pitch is yielded by the Norway Spruce Fir. Balsam is procured from different
CONIFER/E.
CONIFER/C.
CONIFER/E.
Fig. 101.
CEDAB.
CYCADACE/E.
Fig. 97.
WELLINGTONIA GIGANTEA.
The Mammoth Tree of California.
Height 363/f., diameter 31ft.
Supposed age 3000 years.
DIOSCOREACE/E.
Fig. 102.
CYPRESS.
ORCHIDACE/E.
Fig. 103.
CYCAS.
Fig. 104.
YAM PLANT.
Fig. 105.
ORCHID.
ZINGIBERACE7E.
ZINGIBERACE/E.
MARANTACE/E.
Fig. 106.
GINGER PLANT.
MUSACE/E.
Fig. 109.
BANANA.
BROMELIACE/E.
Fig. 107.
TURMERIC.
AMARYLIDACE/E.
Fig. 110.
AGAVE.
LILIACE/E.
Fig. 108.
ARROW-ROOT.
BROMELIACE/E.
Fig. 111.
PINE- APPLE.
LILIACE/E.
Fig. 112.
MANY-HEADED PINE.
Fig. 113.
ALOES PLANT.
Fig. 114.
DRAGON'S-BLOOD TREE.
THE VEGETABLE KINGDOM. 13
species of Fir and Pine. To this order belongs Wellingtonia gigantea, the Mammoth
tree of California, 363 feet in height (about that of St. Paul's Cathedral, London), and
having a diameter of 31 feet. A portion of the bark of one of these trees is placed
round a framework at the Crystal Palace, Sydenham, showing the enormous size of
this giant of the vegetable kingdom. (Figs. 92 to 102.)
180. Cycadaceae, CTCADS. Trees or shrubs, in some respects resembling the
Palms, and in others the Ferns. These plants are found in the warm and temperate
parts of America and Asia, and at the Cape of Good Hope. There are 6 genera and
45 species. These plants yield starch and mucilaginous matter, the latter hardening
into a transparent gum. Some species furnish sago and a kind of arrow-root. (Fig. 103.)
ENDOGENS.
This great class of plants is distinguished by the following physiological peculi-
arities: 1. The wood is endogenous that is, increases by the addition of new woody
matter in the centre of the trunk. 2. The leaves are straight-veined (except in the
sub class, Dictyogenze), and are not jointed to the stem; consequently, do not readily
fail off when dead. 3. The organs of fructification are ternary. 4. The seeds have
only one cotyledon or seed-lobe.
DICTTOGEN^J.
Leaves reticulated. Ilhizomes mostly circular.
181. Dioscoreaceae, YAMS. Twining shrubs, with large tubers, natives of tropical
regions. There are 6 genera, and lip species. Acridity prevails in these plants,
although a farinaceous matter is found in the tubers of some species. The latter, called
Yams, are used in warm countries as a substitute for the potato. (Fig. 104.)
182. SmilaceSJ, "ARSAPARILLAS. Herbs or under-shrubs, often climbing. Found
in the temperate and tropical parts of Asia and America. There are 4 or 5 genera,
and about 120 species. These plants possess mucilaginous and demulcent properties.
The various species of Smilax furnish the sarsaparilla, which is used as a tonic and
alterative.
183. Trilliaceae, PARIDS. Herbaceous plants, with tubers or rhizomes. Natives of
the temperate parts of Europe, Asia, and America. Some are narcotic, others more
or less acrid, and some emetic. Lindley mentions 4 genera, and 30 species.
PETALOIDE^C.
Flowers having usually a Perianth of verticillate leaves, or of a few whorled scales.
Occasionally the Perianth is abortive.
184. Hydrocharidaceae, HYDROCHARADS. Floating or aquatic plants, found chiefly
in Europe, Asia, and North America. Their properties are not important; some are
mucilaginous and astringent. There are 12 genera, and 20 species.
185. OrcMdaceae, ORCHID& Perennial herbs or shrubs, with showy flowers, found
in most parts of the world, and abounding in moist tropical regions. Lindley enu-
merates 396 genera, and about 3,000 species. Some of these plants are fragrant and
aromatic, others are mucilaginous. (Fig. 105 )
186 Zingiberaceae, GINGER WORTS. Tropical herbs, with a creeping rhizome and
frequently showy flowers. Their rhizomes and seeds have aromatic stimulant proper-
ties, and some species yield starch. The rhizome of Zingiber qfficinale constitutes the
Ginger of commerce. Curcuma longa furnishes Turmeric. Amomum, Elettaria, and some
other species, furnish Cardamoms and Grains of Paradise. Curcuma auguslifolia sup-
plies East Indian Arrow-root. There are 29 genera and 247 species. (Figs. 106, 107.)
187. MarantaceaB, MARANTS. Herbaceous plants, with tuberous rhizomes, similar
to the Ginger Family, and natives likewise of the tropics. Lindley mentions 6 genera,
and 160 species. These plants contain starch in the rhizomes and roots. Arrow-root is
supplied by the tuberous rhizome of Maranta arundlnacece and M. indica, as well as
some other species. (See Fig. 108.)
188. MusaceSB, MUSADS, or BANANAS. Stemless or nearly stemless plants, with
leaves sheathing at the base, and forming a kind of spurious stem. Natives of warm
and tropical regions. These plants furnish a large supply of nutritious fruit, and their
leaves yield valuable fibres. It is said that the same extent of ground which in wheat
would only maintain two persons will yield sustenance, under the Banana, to fifty.
Manilla Hemp is the produce of Musa textihs. 5 genera and 21 species. (Fig 109.)
189. IridaceSB, IRIDS. Herbaceous plants, with rhizomes, or under ground corms.
Natives chit fly of warm and temperate regions, and abounding at the Cape of Good
Hope. There are 53 genera, and 550 species. Some species are fragrant and stimulant,
others acrid, and some yield dyes. The rhizome of Iris Florentina furnishes Orris-root.
Crocus sa tivus supplies the dye Saffron, which is also obtained from some other species.
190. Burmanniaceae, BURMANNIADS. Tropical herbs, found in moist, grassy places.
Their properties are unimportant. There are 10 genera, and 35 species.
191. HaBUlodoraceSB, BLOOD-ROOTS. Herbaceous plants, with fibrous roots. Found
14 POPULAR SKETCH OF
in various warm parts of the world. Lindley mentions 13 genera, and 50 species. The
roots of these plants supply a red dye.
192. Amaryllidacese, AMARYLLIDS. Generally bulbous plants, sometimes with
fibrous roots. Natives chiefly of the Cape of Good Hope. Lindley notices 68 genera,
and 400 species, and he divides them into four sub-orders: 1. Amarylleae, bulbs
without a coronet in the flower. 2. Narcisseae, bulbs, with a coronet. 3. Alstrome-
riete, fibrous rooted, sepals different in form from the petals. 4. Agaveae, fibrous
rooted, sepals and petals alike. The bulbs ef many of these plants are poisonous;
some are emetic, and others yield a spirit, The tough fibres of some species, as the
American Aloe (Fig. 110), are used for flax. The juice of this plant yields also an
intoxicating drink.
193. Ilypoxidacese, HYPOXIDS. Herbaceous and frequently stemless plants, with
tuberous and fibrous roots. Natives of warm countries. Some have bitter roots,
others have edible tubers. Lindley mentions 4 genera, and 60 species.
194. BromeliaceaB, BROMEL-WORTS or PINE- APPLES. Stemless or short- stemmed
plants of the warm parts of America chiefly. These plants are more or less epiphytic,
that is, are able to grow without any direct attachment to the soil. The fruit of
Ananassa is the Pine-apple or Ananus, well known for its sweetness and fine flavour.
In its wild state, however, it is excessively acid (Figs 111 and 112). There are 23
genera, and 170 species.
195. Liliacese, LILY-WORTS. Herbaceous plants, shrubs, or trees, with bulbs, tubers,
rhizomes or fibrous roots. They are found both in temperate and tropical countries.
There are, according to Lindley, 133 genera, and 1.200 species. He divides the order
into twelve sub-orders, as follows : 1. Tulipeae, Tulip tribe; 2. Herrnerocallidea?, or Day-
lily tribe; 3. Aloinea3, or Aloes; 4. Scillese, or Squills; 5. Conantherea?; 6. Anthericeas;
7. Aphyllan these; 8. Wachendorflfeae; 9. Asparageas; 10. Aspidistreas; 11. Ophiopogcneae;
12. Convallarieas. Many of these plants are showy garden flowers, as Tulips, Lilies,
&c.; others are used medicinally, as Squill, Aloes, &c. Some yield valuable fibres, as
Phormium tenax, New Zealand Flax. Drucccna Daruco, and other species, supply n
resinous matter called Dragon's-blood. Xanthorrcea hastilis, the Grass-tree of Australia,
which gives a peculiar feature to the vegetation of that region, yields a yellow gum.
The base of the inner leaves of some Grass-trees is also used as food. (Figs. 113,
114, and 115).
196. MelanthaC68B, MELANTHS, or COLCHICUMS. Bulbous, tuberous, or fibrous-
rooted plants, extremely variable in appearance. Found in various parts of the world,
but most abundant in northern countries. There are 30 known genera, and 130 species.
These plants are mostly poisonous; some, however, have valuable medicinal qualities,
and are employed in the cure of gout and rheumatism.
197. Gilliesiaceae, GILLIESIADS. Herbaceous plants, with bulbs. Natives of Chili.
Their properties are unknown. There are 2 genera, and 5 species.
198. Pontederiaceae. PONTEDERADS. Aquatic or marsh plants, without important
properties. They are Ibund in America, the East Indies, and Africa. 6 genera, and
30 species.
199. Xyridacese, XYRIDS. Herbaceous, sedgy plants, with fibrous roots. Natives
chiefly of tropical countries, and without important properties. 6 genera, and 70 species.
200. Juncacese, BUSHES. Herbaceous plants, of the colder regions of the globe.
Many species are used in the manufacture of mats, bottoms of chairs, &c. There are
14 genera, and 200 species.
201. Palmse, PALMS. Arborescent plants, with simple, rarely -branched trunks,
marked with the scars of the leaves. Natives of the tropics chiefly, and imparting
to them much of their botanical physiognomy. " The race of plants to which the
name of Palms has been assigned is, no doubt," says Dr. Lindley, " the most interest-
ing in the vegetable kingdom, if we consider the majestic aspect of their towering
stems, crowned by a still more gigantic foliage; the character of grandeur which
they impress upon the landscape of the countries they inhabit, their immense value
to mankind, as affording food and raiment, and numerous objects of economical im-
portance; or, finally, the prodigious development of those organs by which their race
is to be propagated." There are 73 known genera, and 400 species, but the numbers
are probably much greater. They have been divided into the following tribes:
1. Arecinea3, the Betel-nut tribe; 2. Lepidocaryinae, the Sago tribe; 3 Borassina?, the
Palmyra tribe; 4. Coryphinaa, the Talipot and Date tribe; 5. Coccinae, the Cocoa-nut
tribe. The properties of these plants are very various. In the countries where they
grow they supply food, and are used for forming habitations. Many supply oil, wax,
starchy matter, and sugar, which, fermented, forms an intoxicating beverage. Their
fibres also furnish materials for ropes, cordage, and weaving. Some species of
Calamus furnish canes more than 500 feet in length, which are used as cables. Tliytde-
phas macrccarpa,tlie Ivory Palm, supplies a hard white substance called Vegetable
LILIACE/E.
PALM/E.
PALM/E.
Fig. 115.
AUSTRALIAN GRASS TREE.
PALM/E.
Fig. 118.
WAX PALM.
PALM/E.
Fig. 116.
COCOA-NUT PALM.
PALM/E.
Fig. 119.
OIL PALM.
PALM/E.
Fig. 117.
DATE PALM.
PALM/E.
Fig. 120.
SAGO PALM.
PALM/E.
Fig. 121.
MAURITIA PALM.
Fig. 122.
PALMYRA PALM.
Fig. 123.
DWARF FAN PALM,
PALMXE.
PALMXE.
PANDANACEXE.
Fig. 124.
IVORY PALM.
Fig. 125.
DOOM PALM.
Fig. 126.
SCREW PINE.
ARACEXE.
GRAM IN EXE.
GRAM IN EXE.
Fig. 127.
ARUM.
Fig. 128.
WHEAT AND BARLEY.
Fig. 129.
OATS.
GRAM IN EXE.
GRAM IN EXE.
GRAM IN EXE.
Fig. 130.
RYE AND MILLET.
Fig. 131.
RICE.
Fig. 132.
MAIZE, OR INDIAN CORN.
THE VEGETABLE KINGDOM. 15
Ivory. The Date Palm furnishes food to the tribes of the Desert, and the Doom Palm
of Egypt is called the Gingerbread Tree, from the resemblance of its mealy rind to
that article. Palm oil is obtained chiefly from Elais guineensis, and melanococca, and
these trees are also said to yield the best Palm wine. The Ceroxylon andicola, or Wax
Palm of Humboldt, has its trunk covered with a coating of wax, which exudes from
the spaces between the insertion of the leaves. (See Figs. 116 to 125.)
202. Cominelynaceae, SPIDER- WORTS. Herbaceous plants of warm climates. Some
have fleshy rhizomes, containing a starchy matter, which is used for food. There are
17 genera, and 264 species.
203. Alismaceas, ALISMADS. Aquatic plants, natives both of tropical and tempe-
rate climates. Their properties are unimportant. There are 5 genera and about 70 species.
204. ButomaceJB, BUTOMADS, or FLOWERING- RUSHES. Aquatic plants, often lac-
tescent. Found chiefly in marshes of northern countries. Some of them have bitter
and acrid properties. Lindley mentions 4 genera, and 7 species.
205. Pandanaceae, SCREW-PINES. Trees or bushes, sometimes sending down aerial
roots. Natives of tropical regions, and common in the islands of the Indian Archi-
pelago. There are 7 genera and 75 species. Their flowers are generally fragrant, and
their seeds are used as food. The roots of these remarkable trees are sent down from
all parts of their stems, and appear like artificial props. (Fig. 126.)
206. Araceae, ARUMS. Herbaceous or shrubby plants, sometimes with tubers or
creeping rhizomes. They occur in various parts of the world, abounding in the tropics.
These plants have been arranged in four orders, as follows: 1. Arineae, Cuckoo-pint
tribe. 2. Typhinese, Bulrush tribe. 3. Acoreae, Sweet- flag tribe. 4. Pistieae, Duck-
weed tribe. The order includes 47 genera and 273 species. Their general property
is acridity, and some of the plants are dangerous poisons. The rhizomes of some
species yield starchy matter, and when boiled or roasted are used as food. Some of
these plants send out aerial roots, by means of which they climb upon trees. (Fig. 127.)
207. Naiadacese, NAIADS, or PONDWEEDS. Water plants of both the ocean and fresh
water. They are found in various parts of the world, but have no properties of import-
ance. There are 19 known genera, and upwards of 70 species.
208. RestiaceSB, RESTIADS, or CORD-RUSHES. Herbaceous plants or under-shrubs.
They are found chiefly in America and Australia, and are without important pro-
perties. The tough, wiry stems of some species are used for making baskets and
brooms. There are 36 genera, and 286 species.
209 Cyperaceae, SEDGES. Grass-like herbs growing in tufts, with solid stems,
sometimes creeping, often angular, and without joints. They are found in all quarters
of the globe, and at all elevations; many species occur in marshy ground. Lindley
mentions 112 ge'nera, and 2,000 species. This order includes the Papyrus of the Nile,
the plant anciently used in the manufacture of paper. Some species of Cyperus have
tubers which are used as food, and the roots of others have been employed as bitter
tonics. The stems of some are used for chair bottoms.
210. Gramine33, GRASSES. Herbaceous plants, with cylindrical, hollow, and jointed
stems, called culms. The grasses are found in all parts of the world, and are said to
form about one twenty-second part of all known plants. In tropical regions they
frequently occur as trees. Lindley enumerates 291 genera, including about 3,800
species. To the section of grasses supplying food for man belong the nutritious cereal
grains, as Wheat, Oats, Barley, Eye, Rice, Maize, Millet, &c. Sugar is also obtained
from many grasses, known as sugar canes. To the herbage grasses, affording food for
animals, belong the various pasture grasses, as Rye grass, Meadow grass, &c. In the
warmer parts of the world, the fodder grasses attain the height of five or six feet, but
are yet sufficiently tender to be used as animal food. *(Figs. 128 to 133.)
211. Rhizantlieae, RIIIZANTHS, or RHIZOGENS. Leafless, scaly, parasitic plants,
having a fungus-like appearance, and of a brown yellow or purple colour. These plants
are frequently stemleas, but have sometimes a creeping rhizome. They are found
chiefly in tropical climates, and are employed as styptics. There are 21 genera, and
53 species. To this order belong the species of Rafflesia, gigantic parasites, the perianth
of which is frequently three feet in diameter. (Fig. 134).
CRYPTOGAMOUS, OR CELLULAR FLOWERLESS PLANTS.
ACROGENS.
The most simple form of plants; their structure mostly entirely cellular; their
propagation effected by means of spores.
ACROGEN2E.
Having usually distinct stems, leaves, stomata, some vascular tissue, and thecse or
spore cases.
212. Equisetacese, HORSE-TAILS. Leafless branched plants, with a striated fistular
16 POPULAR SKETCH OF THE VEGETABLE KINGDOM.
stem, in the cuticle of which silex is secreted. Found in rivers, ditches, &c., in various
parts of the world. They are sometimes used for polishing furniture, &c. Lindley
mentions 1 genus, and 10 species. (Fig. 135.)
213. .Filices, FERNS. Elegant leafy plants, occurring chiefly in moist, insular
climates, and abounding in the tropical islands. In warm countries they occur as
Tree-ferns, fifty or sixty feet in height. The properties of the Ferns are in general
demulcent and astringent. The rhizomes of some are used as food, and others supply
tanning material. The syrup called Capillaire is prepared from some species. Liudley
notices 192 genera, and upwards of 2,000 species. (Fig. 136).
214. MarsileaceSB, PEPPER-WORTS. Stemless plants, creeping or floating, found in
ditches and pools. They are not put to any important use. There are 4 genera, and
upwards of 20 species.
215. LyCOpodiaceSB, CLUB-MOSSES. Moss-like plants, with creeping stems, and
imbricated leaves, intermediate between Ferns and Mosses. They abound in moist,
warm, insular climates. These plants have, in their spore cases, an inflammable
powder, called vegetable brimstone, which is employed on the Continent in the manu-
facture of fire-works, and in pharmacy to roll up pills to render them impervious to
damp. There are 6 genera, and 200 species. (Fig. 137).
216. MllSCi, MOSSES. Erect, creeping, terrestrial, or aquatic plants, found in all
moist regions, and abounding in temperate climates. There are, according to Lindley,
46 known genera, and 1,100 species.
217. HepaticSB, LIVERWORTS Plants growing on the earth or trees in damp
places. They are generally distributed over the globe, both in cold and warm climates.
There are 65 genera, and about 700 species.
THALOGEN.ZE, Of CELLULARES.
Structure entirely cellular, without distinct stems, leaves, or stomata.
218. LiclieneS, LICHENS. Plants often spreading over the surface of the earth, or
rocks, or trees, in dry places, as a foliaceous, hard, or leprous substance, called a
thallu?. They are found in all parts of the world, and seem to derive their nourish-
ment principally from the atmosphere. Lichens furnish articles of food and important
dyes; among the former class is the substance known as Iceland Moss. Cladonia
rangiferina is a Lichen upon which the Reindeer feeds. The valuable dyes, Orchil,
Cudbear, and Parietin, are obtained from different species of Lichens (Fig. 138).
Lindley gives 58 genera, and 2,400 species.
219. Fungi, MUSHROOMS. Cellular plants, variable in their consistence, soft or
hard, fibrous or gelatinous, fleshy or leathery. Found in all parts of the world.
There are, according to Berkeley, 598 genern, and 4,000 species. Some species are
edible, as the common Mushroom, Morel, and Truffle; others are poisonous; and some
very destructive, from their parasitical growth. Some Fungi are limited to certain
kinds of decaying matter; thus peculiar species are developed in vinegar, yeast,
flour, &c. The rapidity of their growth is also remarkable. Blight, mildew, rust,
and smut, are diseases in grain due to the attacks of Fungi, as is also dry-rot in
timber. (Fig. 139.)
220. AlgSJ, SEA- WEEDS. Cellular plants found in salt and fresh water, and in moist
places, as on damp rocks, the glass and pots of hothouses, and in hot springs. These
plants have been arranged into five divisions, as follows: 1. Characeae, water plants
formed of parallel tubes, sometimes encrusted with carbonate of lime. 2. Fucaceae, the
Sea- wrack tribe, usually growing in salt water. 3. Floridese, rose or purple- coloured
sea-weeds, with fronds. 4. Confervacese, aquatic plants, consisting of one or more
cells united so as to form an articulated or flat frond. 5. Diatomaceae, crystalline,
angular, fragmentary, and brittle fronds, united by a gelatinous substance. Found in
still waters and moist places. Lindley enumerates 283 genera, and 2,000 species.
Some of the species are very gigantic, others exceedingly minute, requiring a micro-
scope for their detection. The lowest members of the order approach so nearly the
lowest tribes of animals, that it is difficult to draw a line of demarcation. Some
species are said to occur in red and green snow, and the red and green colours of certain
lakes and seas are attributed to these plants. A quantity of gelatinous matter is ob-
tained from these plants, and some of them are used for food, as Carrajeen or Irish
Moss (Fig. 140), Dulse, Tangle, Laver, &c. Kelp is obtained by the burning of Sea-
weeds, and Iodine is also procured from them.
For details of the structure and physiology of plants, see " STEWART'S SYNOPSIS OF STRUCTURAL
AND PHYSIOLOGICAL BOTANY," with 84 Engravings. Price Is. plain ; 2s. coloured. Pub-
lished by JAMES REYNOLDS, 174, Strand.
.
LAWS OF MATTER & MOTION
* c> 8
LAWS OF MATTER AND MOTION.
As no branch of science can be understood without some previous knowledge
of the general properties of matter, it will be desirable to commence by shortly
describing them :
Extension is tne bulk of a body, its length, breadth, and thickness.
Impenetrability is that property by which two bodies cannot at the same
time occupy one and the same place. If a nail be driven into a blocK of wood
it displaces the particles, but does not become incorporated with them (fig. 1).
If in a full glass of water a stone be placed, the water will be forced over to
make way for the stone (fig. 2). If we endeavour to fill a phial by plungiug
it into water, the air will rush out of the-%phial to make way for the water
(fig. 3).
Divisibility denotes the property by which a body is susceptible of being
subdivided into an indefinite number of parts. Animalculse have been found so
small that a grain of sand will cover 300,000 of them, each one having a perfect
organization ; fig. 4 represents the forms of some highly magnified.
Porosity arises from the influence which heat exercises in separating the
particles of matter. The piece of iron B, fig. 6, when cold, will exactly fit
into the hole and notch of A ; but if heated it will do neither. Fig. 7 repre-
sents the action of heat in expanding and setting in motion the particles of
water.
Inertia or Persistence is the tendency of matter to preserve its present
state, whether of rest or motion, unchanged. Fig. 8 illustrates the first : if the
card be struck away the coin will remain balanced on the finger: fig. 9 illustrates
the second : a body in motion has a tendency to proceed in a straight line ; but
the hare being pursued by a dog, turns quickly, and the latter is irresistibly
thrown out of its track and compelled to take a wider turn, thus affording the
hare the only chance of escape.
Cohesion is the force by which the atoms of a body are held together in one
solid mass. It is greater in some bodies than in others, the solidity or weight of
the body corresponding to the cohesive attraction. It is this po.wer which holds
the drop of water suspended at the end of the finger, and keeps its minute
watery particles united (fig. 10). Capillary attraction 1S another effect of
this power which enables liquids to rise above their level in minu-te tubes (fig .11)
Sap ascends in plants by the same force (fig. 12).
Gravitation is that force which causes all bodies on or near the earth to tend
towards its centre with a force proportioned to their respective quantities of
matter (fig. 13). All bodies attract each other inversely as the squares of the
distances. All influences emanating from a central point follow the same law.
Fig. 14 illustrates the law in reference to light. At a certain distance the rays
illuminate the space A B ; at twice that distance they are spread over c D. four
times the former space, but with four times less intensity ; at three times the
distance they illuminate the space E F with nine times less intensity, and so on.
All bodies possess gravity or weight ; there is no such thing as perfect lightness.
Smoke ascends only because it is lighter than the atmosphere (fig. 15). The
force of gravity at the surface of the earth is such that in the first second of time,
it gives to a body allowed to fall, a velocity of 16 feet ; in the next second 48
feet ; in the third second 80 feet. Fig. 16 shows the rate at which bodies fall ;
each of the triangular portions representing 16 feet, the figures on the right, the
seconds.
THE CENTRE OF GEAVITY.
The centre of gravity in a body is that about which all its other parts equally
balance each other. Figs. 17 to 21 show the position of the centre of gravity in
bodies of different forms. The stability of a body resting on the ground depends
greatly upon the centre of gravity. The body will stand provided a vertical line
drawn from the centre of gravity falls within the base (figs. 22, 24). The mass of
rock (fig. 23) will fall because the vertical line falls beyond the base. Bodies
having a narrow base are easily upset, for if they are the least inclined their
centre is no longer supported, as seen in fig. 25. Rope dancers are provided
with a pole, loaded at the ends, for the purpose of bringing their centre of gravity
vertically over the rope (fig. 26).
LAWS OF MATTER AND MOTION.
THE PENDULUM.
This body, represented at fig. 27, depends for its motion upon the forces of
gravitation and persistence. The longer the pendulum the slower are its vibra-
tions, and. as the length is affected by temperature, various contrivances have
been, resorted to to correct this expansion and contraction ; these are termed
compensation pendulums (figs. 28, 29). Fig. 30 represents the balance wheel of
a watch, with a spring, which is expanded or contracted by the lever c, producing
a corresponding effect on the movement of the watch.
CENTRAL FORCES.
These are of two kinds, centripetal, or the force of gravity, tending towards
the centre ; and centrifugal, flying from it. The first may be illustrated by a
whirlpool at sea, or a whirlwind on land (figs. 31 and 32). Centrifugal force
may be illustrated in a variety of ways. If we whirl rapidly a sling with a stone
in it, and suddenly set free the stone, it will proceed in a straight line (fig. 33).
In turning rapidly a circular grindstone in contact with water, the latter will fly
off at right angles (fig. 34). A practical application of this power is seen in the
governor-balls of a steam engine (fig. 35). By any increase in the velocity in
the engine, the balls are thrown apart, and the levers draw down the collar, D,
and with it the end of the lever, F, which thus partially closes the throttle-valve
of the steam pipe.
The centripetal and centrifugal forces are sublimely exemplified in the motions
of the planetary bodies ; the former in their attraction towards the central lumi-
nary by gravitation ; and the latter in their tendency to proceed in e straight
line by the force of persistence.
The velocity of revolving bodies increases in proportion to the distance from
-**/ the centre of motion. The extremities of the vanes of the windmill move over
a much greater space than the parts near the axis, yet describe the circle in the
same space of time (fig. 36). In like manner, as our globe turns on its axis,
those parts nearer the poles describe smaller circles than those more remote -,
the equatorial regions describing the largest circles of all, hence, it follows, that
the equatorial regions move at a far greater velocity than the regions near the
poles (fig. 37).
LAWS OF MOTION,
A body projected by a single force naturally proceeds in the direction of that
force ; but if in its progress a new force acts upon it, it will then be sent in a
new direction. Thus, a ball projected in the line ABC (fig. 38), strikes obliquely
the ledge at c, there meeting an obstacle to its progress, which acts as a new
force, it is caused to rebound in the direction ODE, making the same angle
with the ledge as did the original path of the ball A B c. This effect is com
monly expressed by saying that the angle of incidence is. equal to the angle of
reflection, the former meaning the angle ABC, and the latter e D E ; and this
is a law that applies equally to the motions of sound, heat, and light ; and
therefore, is of the utmost importance throughout physics. If two or more
forces act upon a body at certain angles, a single force may be found which would
produce the same effect. This single force is called the resultant or equivalent.
In fig. 39 we have an example of this : a ball receiving a blow in the direction
A B, and at the same time a blow of equal force in the direction A D, does not
pursue either of those directions, but takes a diagonal course between them to c.
The effect being the same as if the ball had been sent in the direction A c, by a
single force.
The process of finding a single fo*ee^quivalent to two or more forces is called
whe composition of forces, and the^orcss of finding forces which will produce a
motion equal to that of a single force, is called the resolution of forces. In fig.
40, this is illustrated in reference to the action of the wind upon the sail of a
ship, and of the tide upon the helm. Let A B represent the direction of the
wind acting upon the sail E F, placed obliquely to it, then, by drawing A c per-
pendicular to F E, and by completing the parallellogram D c; the diagonal A B is
resolvable into the adjacent sides A c and A D ; now, A c being at right angles to
E F, will have the effect of propelling the yessel, although not in a straight line; but
it may be guided in the desired direction by means of the helm, upon which the
water re-acts by the progressive motioa of the vessel
MECHANICAL POWERS
MECI1MICAL POWERS.
THE mechanical powers are essentially but two in 'number, but are usually
considered as six ; namely, the Lever, the Wheel and Axle, the Pulley, the In-
clined Plane, the Wedge, and the Screw. The three first are assemblages of
levers, and the three last inclined planes. One or more of these powers enters
into the composition of every machine.
Ths LsVSI consists of an inflexible rod or bar, resting on a support called
a fulcrum, for the purpose of raising, by a power applied at one end, a weight at
the other. The advantage gained is in proportion to the greater distance of the
power from the fulcrum, than is the distance from the fulcrum to the weight to
be raised ; thus, if the distance from the power to the fulcrum be five times
greater than the distance from the weight to the fulcrum, a force of one pound
in the power will balance five in the weight.
There are three kinds of levers ; the first kind is that where the fulcrum
(F) is placed between the ws ight (w) and the power, (p, fig. 1). The com-
mon balance, (fig. 2) is a lever of the first kind, as is also the Roman steel-
yard, (fig. 3).
The boy'-s amusement of see-saw (fig. 4) is another illustration of a lever of
the. first kind, the bigger boy taking the shorter end of the plank, that his lighter
companion at the longer end may balance him.
Fig. 5, shows the application of a lever of the first kind in moving a heavy
body ; the nearer the fulcrum to the body to be moved the more powerful
being the leverage.
In levers of the second kind, the weight is situated between the power and
the fulcrum, (fig. 6). This kind of lever is seen in the common wheelbarrow,
where the wheel is the fulcrum, the load in the barrow the weight, and the
power the man who holds up the shafts. The oars of a boat present another
instance ; here the water is the fulcrum against which the blades of the oars
press.
Levers of the third kind are those where the fulcrum is at one end, the weight
at the other, and the power between them, (fig. 7). Here the power acts with a
considerable disadvantage, and this kind of lever is only used where the object is
to produce great velocity, and which can only be effected by an expenditure of
power. The footboard of a common turning lathe affords an example of this
kind of lever. But one of the most striking instances of it is seen, in the human
irm in the act of raising a weight in the halul, when the lower part of the arm
becomes a lever of the third kind, the elbow joint being the fulcrum, and the
muscles which move the arm, the power (fig. 8). The muscle, by contracting
its fibres less than an inch, raises the hand twenty inches ; and if it raises also a
weight of twenty-five pounds in the hand, it must act with a force at least twenty
times as intense, or of five hundred pounds ; thus showing the extraordinary
strength of the living muscle.
Levers may be combined in a great variety of ways, and the aggregate effect of
such combination is as the product of the effect of thcj separate levers. Fig. 9,
represents a combination of levers of the first kind, in which the power of i^ie
small weight P brings down A, which raises B, bringing down c, and conse-
quently raising D ; and thus, if properly supported, will balance the large weight
w. By this means a weight of one pound will balance one of a hundred and
twenty pounds.
The Wheel and Axle ma J be considered as a kind of perpetual lever, of
which the fulcrum is the centre of the axis, and the long and short arms the
radius of the wheel and the radius of the axle, as shown at fig. 10 ; the power P
acting upon the weigh* w, through the intervention of the lever A B, whose
fulcrum is the centre of the axle. Supposing the semi-diameter of the wheel
to be six times greater than the semi-diameter of the axle, a power of one
will balance a weight of six, exactly upon the principle of a lever of the first
kind.
There are many modifications of this mechanical power ; one of the most com-
mon is the windlass for raising water from a well by means of buckets, (fig. 11).
The capstan used on board ships is an upright axle, the moveable bars or
levers acting as the wheel (fig. 12). Like the lever, the wheel and axle may
be used in combination, the circumference of one wheel acting by means of
teeth upon the axle of another, as shown at fig. 13 ; the effect of such
combination being similar to that produced by the combination of levers already
described.
MECHANICAL POWERS.
The compound axle, (fig. 14), is s contrivance by which the power is increased
without increasing the diameter of the wheel. This axle has one half of it twice
the diameter of the other half. A moveable pulley being attached to the weight
to be raised, the rope is passed round the wheel, and coiled in the same direction
upon both parts of the axle: upon every revolution of the axle, a portion of the
rope equal to the circumference of the thicker part will be drawn up, but at the
same time, a portion equal to the circumference of the thinner part will be let
down : hence, every revolution of the cylinder raises the weight through a space
equal to half the difference between the circumferences of the thicker and thinner
parts of the axle.
The Pulley is a sma11 wheel turning on an axis, and having a groove upon
its circumference for the reception of a rope. It is either fixed or moveable. The
fixed pulley (fig. 15) possesses no mechanical advantage, but is used to change
the direction of the power, or to give convenience in pulling.
The moveable pulley, however, affords mechanical assistance by dividing the
weight. This is illustrated at fig. 16, where the weight of the barrel is equally
divided between the part of the rope affixed to the beam, and that held in the
hand. Fig. 17 shows this more clearly; if the large weight be twenty pounds,
ten pounds is borne by A, and ten pounds by p. The fixed pulley, B, is of no
other use than to change the direction of the power.
The power of pulleys is increased by their combination. Fig. 18 illustrates
this : here the weight is equally distributed between four ropes, consequently it
may be supported by a power only a fourth of its own weight. Fig. 19 is a sys-
tem of pulleys, or a tackle, as it is usually called, by which a power of one
hundred will balance a weight of six hundred. Fig. 20 exhibits a system of pulleys
in combination, in which a power of one will balance a weight of sixteen. The
power of this system may be greatly augmented by substituting fixed pulleys for
the hooks to which the ends of the ropes are attached, in the manner shown at
fig. 21. In order to obviate the loss of power occasioned by the friction of the
separate axles, where several pulleys are employed, an ingenious arrangement has
been resorted to in White's patent pulley (fig. 22), by which all the pulleys in
each block turn on the same axis.
The Inclined Plane* It is not difficult to understand that a body may
with much greater ease be drawn up a slope, than it can be raised the same height
perpendicularly. Hence the advantage of the inclined plane, which acts as a
mechanical power, in partly supporting the weight (fig. 23). The -.longer the
inclined space is in proportion to the perpendicular height, the greater is the
advantage afforded. Suppose the inclined plane A B (fig. 24), to bear the pro-
portion to the perpendicular height B c, as three to one, then a power of one will
balance a weight of three.
Persons have often been struck with astonishment when viewing Stonehenge,
how those enormous cross-pieces of stone were raised to the elevation at which
we see them, but the mechanical feat is by no means very wonderful, for it
would only be necessary to raise an inclined plane of earth in the direction
of the line A B (fig. 25), and by means of rollers placed under the stone, pass
it to its situation on the top ; the earth being removed, the stone would remain
secure.
The Wedge is a combination of two inclined planes united at their base
(fig. 26). The wedge derives its great power chiefly from the way in which the
force is applied by being struck.
The Screw is a machine of great mechanical power, and is a modification of
the inclined plane, as will be seen by reference to fig. 27. The screw has no
power by itself, it can operate only by working in spiral grooves corresponding
to its threads : these grooves are formed on the inside of a box or nut,
through which the screw winds itself. Fig. 28 shows the screw, and its nut,
fig. 29, exhibits the screw with a section of the nut, showing the spiral groores,
The power is applied by a lever, the screw, therefore, acts with the combined
power of the lever and the inclined plane, thus becoming in reality a compound
machine.
Screws are much used in presses of all kinds. The bookbinders' standing
press (fig. 30), affords one of the best examples of this application of its
powei.
HOROST1TIC3.
THIS department of science treats of the pressure and equilibrium of liquids,
the most remark-able property of which is, that of equality of pressure. This
property arises from the extreme minuteness and independent gravitation of each
of the particles, and from the manner in which they act upon each other ;
being arranged, not perpendicularly one above the other, but obliquely, as shown
at fig. 1. One particle above pressing between two particles beneath, the
latter consequently sustain a lateral pressure, just as a wedge driven irko a
piece of wood separates the parts laterally. This lateral pressure is the
result, therefore, of the pressure downwards, or the weight of the liquid above.
Fig. 2 illustrates the different degrees of force with which water flows from
apertures in a vessel at different heights. Fig. 3 represents part of a teapot,
which we suppose to be filled with columns of particles of water ; the particle 1,
at the bottom, will be pressed laterally by the particle 2, and thus be forced into
the spout, where, meeting with the particle 3, it presses it upwards, and this
pressure will be continued till the water in the spout has risen to a level with
that in the pot.
Fig. 4 is another illustration of the upward pressure of water. A is a glass
tube, widened at the lower end, against which, by a string passing up the tube, a
thick piece of metal is held close by the hand. Upon immersing the glass and
plate thus held together in the water to a certain depth, the hand may be with-
drawn from the string, the upward pressure of the water being sufficient to sup-
port the piece of metal.
Several interesting illustrations can be offered to prove the remarkable fact,
that the pressure of water on the bottom of the containing vessel does not at all
depend on the quantity of water, but upon the size of the base and the perpen-
dicular height at which the water stands.
Figs. 5 and 6 represent two vessels of precisely similar capacities, and each
containing the same quantity and weight of water, but which have very different
pressures upon their bottoms ; that upon c D being less than the absolute
weight of the water, viz., the weight only of the cylindrical column, A B c D ;
while that upon o H is more than the absolute weight of the water, viz., the
weight of a cylindrical column, E F G H, for the water in the central column
G H I K, presses laterally with the same force, as it does on the part ou which
it stands ; and thus an uniformity of pressure is exerted over every part of the
bottom.
Fig. 7 illustrates the latter case still more strikingly : F is a tube communi-
cating with the chamber, E E, and on these being filled with water, the pressure
upon the bottom, c D, will be precisely the same as if the whole space, A B c D,
were filled with water.
Fig. 8 represents the hydrostatic bellows, which has been contrived to exem-
plify the great effect of a column of water. The tube A communicates with the
interior of the bellows, and upon these being Glled with water, the upper board, B
will be raised, and enabled to sustain a very considerable weight; for if the tube
A hold but an ounce of water, and have an area equal to the thousandth part of
the area of the top of the bellows, the ounce of water in the tube will sustain a
thousand ounces placed on the bellows.
Another important principle in reference to liquids is their tendency to seek an
uniform level. If we pour water into a bent tube, as fig. 10, it will stand at as
equal height in both limbs.
If there be two tubes or limbs of a tube connected together, however different
their width or form may be, a liquid poured into them will stand at the same
level in both, and thus a portion, however small, will balance a portion, however
large, as shown at fig. 11.
Fig. 12 represents a number of vessels of different forms fixed in the vessel
A B, so as to communicate with it, and by means of it with each other. Water
being poured into any one of them will stand at the same level in all, as shown
by the line, c c.
From these' considerations, a most important conclusion follows, namely, that
water will, by being confined in pipes or close channels, rise to the height from
whence it came ; and upon this principle depend all the useful contrivances for
conveying water into to.vns and houses by pipes from distant reservoirs.
References to figs. 1'3 and 14 will illustrate this more clearly.
Fig. 13 represents the water level, and tig. 16 the spirit level.
HYDROSTATICS.
Intermitting Springs- Those springs which flow and stop by regular
aternations may be accounted for upon the principle of the syphon, represented
at fig. 17. If this tube be filled with water, and the shorter leg be plunged into
a vessel of water, the water will flow up the tube, over the bend, and out at the
longer leg, till the vessel is emptied.
Fig. 18 represents a section of a hill, having within a cavity, A, from which
runs a channel in the form of a syphon ; the rain falling upon the hill, preco-
lates through the crevices and pores, d d d, and in course of time will fill the
cavity with water up to the level, E E ; it will then flow over the bend, B, and
continue to flow and supply the spring till the level of the water falls below the
mouth of the channel, when the action of the syphon will cease, until, by fresh
supplies, the level of the water is again raised, so as to flow over the bend, when
the syphon will act as before.
The Hydrostatic Press- Fig. 19. This is perhaps the most powerful
machine ever invented, the only assignable limits to its power being the strength
of the materials of which it is formed. A is the force pump, by the action of
which water is forced through the small tube, B B, and its pressure communicated
to the mass of water in the cylinder, c, there the water in its endeavour to resist
compression forces up the moveable piston, D D, with its burden, and the action
of the pump being continued, the pressure is gradually increased until the
required degree is produced.
Fluid Support Specific Gravity- A solid body immersed in a fluid
displaces exactly its own bulk of fluid, and the force with which the body is
buoyed up, is equal to the weight of the fluid which is displaced ; therefore, the
body will sink or swim, according as its own weight is greater or less than the
bulk of the displaced fluid. This refers to bodies of less density than water.
Any body of greater density than water, when wholly immersed in that fluid,
loses exactly as much of its weight as the weight of an equal bulk of the water
which it displaces.
These laws are of much importance, as an acquaintance with them enables us
to explain innumerable phenomena in nature, in reference to the floating of bodies
in water, or in the atmosphere.
Fig. 20 is a vessel of water, and A a solid body of the same density im-
mersed in it, and which, being equally pressed upon from above and below,
retains its position, just as the mass of water it has displaced would have done.
But if a solid body as B, fig. 21, heavier than water, bulk for bulk, be placed in
it, it will sink to the bottom ; while a body lighter than water will float on the
surface partially immersed, as A, fig. 21, the weight of the water displaced
being equal to the weight of the whole solid. Thus, the weight of any floating
body may be ascertained by measuring the quantity of water which it displaces.
F'ig. 22 represents the hydrostatic balance used for ascertaining the specific
gravity of solid bodies, which are suspended in water by a horse-hair attached
to the bottom of the scales.
Hydrometers- These are instruments which, beittg immersed in liquids,
determine the proportion of their densities, or specific gravities, and thence their
qualities. The use of the hydrometer depends on the following propositions :
1. The hydrometer will sink in different fluids in an inverse proportion to the
density of the fluids. 2. The weight required to sink a hydrometer equally
far in different fluids will be directly as the fluids. Each of these two proposi-
tions gives rise to a particular kind of hydrometer; the first with the graduated
scale, as fig. 23, the second with weights, usually hollow glass beads of various
weights, which are dropped into the liquid till one is found to remain stationary,
indicating t8e density of the liquid.
Fig. 24, represents Nicholson's hydrometer, consisting of a hollow copper ball
A, with a steel stem B, supporting a small dish c. By the successive addition of
weights to the dish c, the instrument may be sunk so as to obtain the complete
range of specific gravity.
Fig. 25, represents the areometer, an instrument for determining the relative
specific gravities of any two fluids which may be poured together without mixing,
as mercury and water, oil and water, &c.
HYDRAULICS
HYDRAULICS.
THIS? science, which may be considered a branch of hydrostatics, treats of
liquids in motion.
The particles of liquids flow over and amongst each other with less friction
than over solid substances, and all the substances gravitate independently. If a
hole be made in the bottom of a vessel the liquid will flow out ; those particles
directly over the orifice being discharged first, their motion causes a temporary
vacuum, into which the particles tend to flow from all directions ; and thus the
whole mass of the water is set in motion (fig. 1). As water flows through
bended pipes to the same level from whence it proceeds, it enables us to form
jets or fountains (fig. 2). If, for example, a body of water be collected in a
reservoir on the upper part of a house, and a tube descending from it to the
garden be made to turn upwards, having a very small bore, the water will spurt
up in a jet to nearly the same height as the surface of the water in the reservoir.
It will not rise quite so high on account of the resistance of the air, and the
effect of gravitation. Most of the ornamental fountains in public gardens are
formed upon this principle.
Pumps and Machines for Raising Water- These may be divided
into four classes. First, those machines in which water is lifted in vessels by the
application of some mechanical force to them. The earlier hydraulic machines
were constructed on this principle ; such as the Persian wheel (fig. 3), consisting
of upright buckets attached to the rim of a wheel moving in a reservoir of water ;
the buckets are filled at bottom as they pass through the water, and emptied at
top ; the water is thus raised to a height equal to the diameter of the wheel:
The Archimedean screw (fig. 4), and the chain pump (fig. 5), are modifications of
the same principle.
The second class of machines are those in which the water is raised by the
pressure of the atmosphere, and comprises all those machines to which the name
of pump is more particularly applied. These act entirely by removing the pres-
sure of the atmosphere from the surface of the water, which may thus be raised
to any height not exceeding thirty-two feet.
Fig. 6 represents the common pump, which consists of a cylinder, with an
air-tight piston, h'aving a valve, A, opening upwards. When the piston is raised
a vacuum is raised in the tube beneath, which is immediately occupied by the
water ; on depressing the piston, the water passes through the valve, -A, in its
centre, and on being raised, the water is lifted to the top of the barrel, and flows
through the spout. To prevent the water returning to the well when the
piston is depressed, a valve (B) opening upwards is placed near the bottom of the
pump.
When it becomes necessary to raise water to a greater height than thirty-two
feet, the third class of machines, or those which act by compression on the water,
usually by the intervention of compressed air, are employed. All pumps of this
description are called forcing pumps, and by these water may be raised to any
height by applying sufficient force.
Fig. 7 represents the forcing pump, consisting of two parts, or barrels, one
similar to the common pump, and the other rising by its side. The water is first
raised in the former part in the same manner as in the common pump, excepting
that the piston has no opening valve, but is solid, and the air is forced out
through the valve, A, into the adjoining barrel. Through this valve the water is
also forced, and the pressure of the descending piston causes it to flow up the
ascending pipe and issue out of the top. The vessel in which the lower end of
the ascending pipe is placed, encloses a volume of air ; when the water rises this
air is compressed, and being elastic it re-acts upon the water, thus causing it to
flow upwards with greater force.
The fire-engine is an interesting example of the utility of this machine ; its
principle will be readily understood by reference to fig. 8. A is the suction-pipe
by which water is supplied from the street main ; B B are two valves opening
upwards into the barrels of two forcing pumps, containing solid pistons ; from
the lower sides of the pump-barrels proceed force-pipes, which communicate
with an air-chamber, c c, by valves, D D, opening upwards into it. Through the
top of the air-chamber descends nearly to its bottom a pipe. E E. vo tjie uppeij
part of which is attached the hose for directing a stream of watt-;i on thjp^re.. By
the alternate action of the pistons, water is drawn through the' valfes *B*B, *aad
HYDRAULICS.
propelled through the forcing valves, D D; and the enclosed air being 4 compressed,
re-acts upon the water, which is projected up the centre pipe and along the hose
with a force proportioned to the power applied to the pistons by the persons
who work the engine.
The fourth class of hydraulic machines for raising water consists of such
engines as act either by the weight of a portion of the water which they have to
raise, or of the water, or by its centrifugal force, momentum, or other natural
powers. The centrifugal pump (fig. 9) belongs to this class. This machine
raises water by means of the centrifugal force, combined with the pressure of
the atmosphere. A B is an upright spindle, so fixed that rapid rotary motion
may he communicated to it by a wheel and pinion, or winch, c D, c D, repre-
sent any number of curved pipes BO disposed and fixed to the spindle that their
lower ends may be near to 't, and be covered by the water to be raised, and their
upper ends to be extended to a considerable distance from the centre of motion,
and bent downwards to prevent the scattering of the water. Before putting the
machine in action the several pipes must be rilled with water, which will be re-
tained in them by a valve near the bottom opening upwards. The machine is
then put in motion by turning the spindle rapidly. The upper ends of the pipes
will describe a much larger circle than the ends below, and, consequently, such a
centrifugal force will be generated at the upper ends as will produce a vacuum,
and the water below will then rise and flow from the upper ends of the pipes
into the circular trough, whence it may be delivered by a pipe as required.
Power to be derived from Water- Motion is generally obtained from
water either by exposing obstacles to the action of its current, as in water-wheels,
or by arresting its progress in raoveable buckets or receptacles, which retain it
during its descent A water-wheel consists of a hollow cylinder or drum, re-
volving on a central axle, from which the power is communicated ; while the
exterior surface is occupied by float-boards, or cavities upon which the water is
to act. Water-wheels are divided into three classes first, the Undershot wheel
(fig 10), having floats dipping into the water, the current of which, acting
against them, causes the wheel to revolve. The second 'class are those termed
Overshot wheels (fig 11), in which the circumference is occupied by a series of
cavities, into which the water falls from above ; as the wheel revolves these
cavities become inverted and discharge their contents at the bottom of the
wheel. This description of wheel is much more powerful, as well as much more
economical in its consumption of water, than the preceding. The third kind of
watei'- wheel is that termed the Breast wheel. In this the water is delivered
about half-way up it, or rather below the level of the axis, and the brickwork
upon which the water descends is built in a circular form, so as to make it
parallel to the edges of the float-boards of the wheel ; its arrangement and mode
of action will be readily understood by reference to fig. 12.
Fi. 13 represents Barker's mill, a machine which owes its efficacy to the
centrifugal force. It consists of a long cylindrical pipe, having a funnel at A,
and terminating in a pivot, turning in a socket, at B. About A is an axis c,
passing through a frame, and carrying with it the upper millstone. At the
bottom of the pipe at B, is a cross pipe, D E, at the opposit- 1 sides of which arc t\vo
aperture;', from which the water poured into the funnel at A, spouts with
considerable velocity, and, from the resistance of the air, gives motion to the
machine.
PNEUMATICS
"or BAROMETER IN INCHES
L .
1 Himalaya 2fiLOOOfeet. 2 .Ar.de s 2.^250 feet. 3 Alp* 16650 feet. 4 Bru
5Siiow(ion3i571eet. 6^r(TreeTisBal]ooTiml837, 27,(.H"Hi feet.
SEA LEVEL
436') feel.
PNEUMATICS.
THIS branch of science treats of the nature and properties of the atmosphere,
and of their effects upon solid and fluid bodies. The atmosphere is a thin
gaseous substance, which envelopes the earth on every side to the height of about
forty-five miles, its density decreasing with its height. Fig. 1, represents the
atmosphere, which is divided by lines into thirty spaces, each of which contains
the same quantity of air, the lower layers being so much compressed by the
weight of those above them, that the lower half of the atmosphere lies within
about three and a half miles of the earth's surface, while the upper half is so
expanded as to occupy upwards of forty miles. The upper thirtieth part alone
occupies more space than all the remaining thirty-nine parts.
Mechanical Properties of Air. The most essential point in which air
differs from other fluids is by its elasticity ; that is, its power of increasing or
diminishing its bulk, according as it is less or more compressed. Air possesses
the universal properties of matter. Its impenetrability may thus be shown :
Fig. 2, is a vessel partly filled with water, upon the surface of which floats a
small cork ; fig. 3 is a smaller cylindrical glass vessel, with a stop cock, which is
closed. If this vessel be inverted over the cork, as at fig. 4, and its mouth
pressed into the water, it will be fonud that the water will not enter the inverted
glass, except to a very limited height, owing to the air in the glass excluding the
water ; but if the stop cock be opened, the air will escape, and the water rise to
the same level within as it is without the glass.
That air is inert and moveable, we have many and familiar proofs, as the
resistance it offers to a body passing through it, and the force exerted by the
wind. It also possesses weight, one hundred cubic inches weighing about thirty-
one grains.
Laws of Air- First, the pressure of the air is equal in all directions ; second,
its degree of pressure depends on the vertical height, and is in proportion to its
density, and to the weight of the fluid displaced.
That air presses in all directions may be proved by filling a bladder with that
fluid, and then pressing upon it; the pressure will be freely communicated
through the mass, and the confined air will rush out with equal force at whatever
part a hole is made in the surface.
The pressure depending on vertical height or depth of air, is an important
property of the atmosphere, and on it depends the explanation of numerous
phenomena.
Air being a substance possessing gravity, necessarily presses downwards in the
direction of the centre of the earth ; and, therefore, the degree of pressure on,
any given point will be equal to the weight of the column of air above that
point, and proportional to its density. The atmosphere is of the greatest
vertical height at the level of the sea, and here its pressure is about fifteen
pounds on every square inch of surface. The pressure being exerted upwards
sideways, obliquely, and in every other direction, as well as downwards.
Some illustrations may be given of the pressure of the air. Figs. 5 and 6
represent two hollow hemispheres of brass ; these being placed in contact and the
air withdrawn from the interior, the external air will exert a pressure of 15 Ibs.
upon every square inch of their surface, so that if two persons pull the handles
in opposite directions they will be unable to separate the hemispheres. The
common leather sucker (fig. 7) with which boys raise stones, acts from the
pressure of the atmosphere. It is the pressure of the atmosphere which causes
liquids to rise in pumps and syphons.
The Barometer- This instrument consists of a column of mercury, sup-
ported in a tube by the pressure of the atmosphere, and therefore indicating that
degree of pressure (fig. 8). It is formed by a glass tube about 34 inches long,
closed at one end and open at the other. The tube being filled with mercury, the
open end is stopped with the finger to prevent any running out, and the tube
being inverted, the open end is placed in a small cup of mercury, and the finger
being withdrawn, the mercury in the tube now subsides three or four inches,
above the top of which in the tube is a perfect vacuum. The tube being then
fixed to a graduated frame, we have a barometer. The mercury will stand in the
tube at the height of from 28 to 30 inches, according to the state of the air ; and
the reason of this is, that the pressure of the whole atmosphere will not raise
PNEUMATICS.
a column of mercury higher than about 30 inches j that is, a column of air equa*
to the height of the atmosphere, from the level of the sea, is of the same weight
as a column of mercury 30 inches high, the one thus balancing the other. The
figures at the sides of fig. 1, show the height of a column of mercury at different
elevations : the barometer thus becomes an important means of determining the
altitude of mountains.
The wheel barometer is represented at fig. 9. The tube is closed at the top,
and bent upwards at its lower extremity, which is open, and the mercury buoys
ip a small float, F, to which a thread is attached, passing over a pulley and ter-
minating in the little ball, w. The friction of the thread on the pulley turns an
index which points to the words on the dial plate.
When the mercury falls in the barometer, an indication is given of diminished
pressure ; and as this causes the air to expand and become sensibly cooled,
moisture is likely to be precipitated in the form of rain.
The Ail Pump- Air may be artificially withdrawn from a containing ves-
sel by means of an apparatus called the air pump, represented at figs. 10 and 11
(the latter showing the pistons and valves). A is the receiver, resting in close
contact with the pump plate B, near the centre of which is the open end of the
tube c c, communicating with the exhausting barrels D D ; these are fitted with
pistons having valves opening upwards, so as to allow the air beneath to pass out
but preventing its return. At the bottom of the barrels are two other- valves
also opening upwards, admitting the air from the tube into the barrels when the
pistons are raised, and on their descent preventing its return ; the air thus con-
fined in the barrel, by the descent of the piston, becomes compressed, and forc-
ing open the valve in the piston, escapes into the open air. The pistons are con-
nected by a rack and pinion movement with a handle, and are raised alternately,
thus producing a vacuum beneath the receiver. By means of the air pump many
interesting experiments in pneumatics may be performed. When the air is
thoroughly exhausted, light and heavy bodies fall with equal swiftness: most
animals die immediately ; vegetation stops ; combustion ceases ; gunpowder will
not explode ; heat is slightly transmitted ; a bell sounds faintly ; magnets are
powerless ; glowworms give no light ; and watery and other fluids turn to
vapour. We thus see the important uses of the air in supporting life, vegetation,
and combustion ; in forming a medium for conveying to us the sound of each
others voices ; besides contributing in numberless ways to our comfort and
enjoyment.
Air Condenser* Fig' 12 represents a section of the condensing syringe,
having an opening at A to admit the air, and a valve at B opening downwards.
The air being forced by the piston through the valve B, is prevented from return-
ing by the form of the latter. Fig. 13 represents a vessel partly filled with
water. By means of the condensing syringe, a large quantity of air may be
forced through the tube into the space A A ; the stop cock being then closed and
the syringe detached, and the stop cock being again opened, the pressure of the
air upon the surface of the water will force it up in the form of a jet d'eau. The
elastic force of compressed air is very great, and is sometimes employed for the
projection of balls from the air gun (fig. 14).
Air Balloon- The air balloon (fig. 15) is a light silken bag of large dimen.
ions, filled with a gas, which bulk for bulk, is lighter than air, so that, when in-
flated, the machine becomes lighter than the air which it displaces, and this differ-
ence is so considerable that it is enabled to carry up with it several persons in a
car attached. As it ascends, the air becoming less dense, the difference between
its weight and that of the air displaced is gradually diminished, until it attains
such a height that the air it displaces is so rare, as to be only equal in weight to
the balloon; this, therefore, becomes the limit of its ascent. In order to descend
the bulk of the balloon is diminished, by the gas being allowed to escape by open-
ing a valve ; thus, the weight of the balloon is made to exceed that of an equal
bulk of air and it accordingly falls.
The Diving Bell- Fig. 16. This machine is formed of iron, and is usually
capacious enough to hold three or four persons. It is constructed on the impene-
trability of air, before described. Air is pumped in from above by means of a
forcing air pump,or condenser ; the water is thereby prevented from rising in
the machine, and the persons within are enabled to breathe freely. A represents
the pipe conveying the fresh air from force pumps, and B the pipe conveying the
ritiated air from the bell.
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OPTICS.
OPTICS is the science of light and vision.
All visible bodies may be divided into two classes self-luminous and non-lu-
minous. The first comprise those bodies which shine by their own light, as the
stars, sun, flames, &c. Non-luminous bodies are those which have no power of
discharging light of themselves, but which throw back the light that falls upon
them from self-luminous bodies. Light emitted from a self-luminous body is
projected in straight lines in every possible direction, so that the luminous body
not only seems the general centre whence all the rays proceed, but every point
of it may be considered as a centre which radiates light in every direction (fig. 1).
A ray of light is a straight line of light projected from a luminous body, and a
pencil of rays is a collection of rays proceeding from any one point of a luminous
body (fig. 2).
When rays of light meet with an opaque body through which they cannot pass,
they are stopped short in their course, and cause the opaque body to form a
shadow on the other side of it. If the luminous body (as A, fig. 3) be larger
than the opaque body (B), the shadow will gradually diminish in size till it ter-
minates in a point ; if smaller, the shadow will increase in size, as it is more
distant from the object that projects it (fig. 4). A number of lights in different
directions, .while they decrease the intensity of the shadows, increase their num-
oor 7 which corresponds witnthat of the lights (fig. 5).
Reflection Of Light- When a ray of light falls perpendicularly on an
opaque body, it is reflected back in the same line towards the point whence it
proceeded ; if it falls obliquely, it is reflected obliquely, but in the opposite direc-
tion, the angle of reflection being equal to the angle of incidence (fig. 6).
The principle of reflection may be illustrated by the case of a plane mirror or
looking glass (A B. fig. 7). The ray from the eye of the spectator at c will be
reflected in the same line C A ; but the ray D B, coming from the foot, in order
to be seen at the eye, must be reflected in the line B c, and therefore the foot
will appear behind the glass at E, along the line c B E.
There are three kinds of mirrors used in optics ; the plane or flat, the convex,
and the concave. A convex mirror has the peculiar property of making the
reflected rays diverge ; and a concave mirror makes the rays converge.
M N, fig. 1, represents a convex mirror formed of a portion of the exterior of a
sphere, whose centre is o. ABC are three parallel rays, the middle one of which
only is perpendicular to the centre of the mirror, and is reflected in the same
line ; the two others falling obliquely, will be reflected obliquely to G and H, the
dotted lines, P P, being perpendiculars which divide their angles of incidence and
reflection. By continuing the reflected rays G B and H E, backwards, they will
meet at F, their virtual focus behind the mirror.
If A B, fig. 9, be an object placed before the convex mirror (M K), and lines
be drawn from its extreme points A B, to o, the centre of the sphere, a diminished
representation of the objects will be formed at the focus.
Fig. 10 illustrates the property of a concave mirror. ABC are three
parallel rays, which, striking the mirror, are reflected, the middle ray in the same
line, and the two others converged so ^s to meet at the focus F, midway between
the surface of the mirror, and the centre of its concavity c. The dotted lines P P,
are perpendiculars.
Images reflected from concave mirrors appear larger than the real objects, pro-
vided these objects are within the focus, as A B, fig. 11.
A B, fig. 12, is an object placed at some distance in front of a concave mirror.
In this case, a small and inverted image of the object will be formed at D E.
When the object is placed at D E, a magnified representation of it will be
formed at A B.
Concave mirrors are used as burning glasses (fig. 13).
Refraction Of Light* Refraction is the effect which transparent mediums
produce on light on its passage through them. Opaque bodies reflect the rays j
transparent bodies transmit them ; but it is found that if a ray, in passing from
one medium into another of different density, fall obliquely, it is turned out of
its course, or refracted ; but if it fall perpendicularly it is not refracted, but pro-
ceeds through the new medium in its original direction.
Let fig. 14, be a vessel half filled with water. If a /ay strike it in the
perpendicular direction, A B, it will be continued in the same line to c ; but if a
ray be admitted at D, it will strike the water obliquely at B, when it will become
subject to two opposite forces, the attraction of the water endeavouring to draw
perpendicularly to c, and the projectile force of the 3fay inducing it to proceed
in its original direction to F ; the consequence will be, that it will pursue an
intermediate course to E.
If a coin be placed in a basin, so that on standing at a certain distance it be
just hid from the eye of an observer by the edge of the basin, and then water be
poured in by a second person, the first keeping his position, as the water rises
the coin will become visible, and will appear to have moved from the side to the
middle of the vessel (fig. 15).
These facts lead to an important axiom in optics ; namely, that we see every-
thing in the direction of that Line in which the rays approach us last. Hence,
the sun is seen several minutes before it comes to the horizon, and as long after
it has sunk beneath it, because its rays strike first upon the atmosphere, and are
by it refracted, or bent towards the earth (fig. 16).
In passing through a pane of glass the rays suffer two refractions, but which,
being in contrary directions, produce nearly the same effect as if no refraction
kad taken place. A A, fig. 17, represents a thick pane of glass seen edgeways.
When the ray B approaches the glass at c, it is refracted to D ; at that point,
returning into the air, it is again refracted, but in a contrary direction, and in
consequence proceeds to E. But this is the case only when the two surfaces
are parallel to each other j if they are not, the two refractions may be made ( in
the same direction. Thus, when the parallel rays (fig. 18) fall on a piece ' of
glass having a double convex surface, that ray only which falls in the direction
of the axis of the lens is perpendicular to the surface : thp- nt.hr.r rays falling
obliquely are refracted towards the axis, and meet at a point beyond the ic, nn
called its focus.
Figs. 19 to 23 represent sections of lenses of various forms, having different
refractive properties. The property of those which have a convex surface is to
collect the rays of light to a focus ; and of those having a concave surface to
disperse them. The rays falling on the concave lens, fig. 25, will each be at-
tracted towards its thicker extremities, both on entering and quitting it ; and
will, therefore, by the first refraction be made to diverge to A c, and by the
second to d e The ray B, falling perpendicularly on the axis of the lens, suffers
no refraction.
Lenses which have one side flat, and the other convex or concave, as figs. 19
and 20, are called plano-convex and plano-concave. The focus of the former is
at the distance of the diameter of the sphere, of which the convex surface of the
lens forms a portion, as shown at fig. 26.
Fig. 24 represents a section of a prism, the principal use of which is to enable
us to decompose the rays of light.
Decomposition Of Light- White light, as emitted from the sun, or other
luminous body, is found to be composed of seven different kinds of light ; namely,
red, orange, yellow, green, blue, indigo, and 'violet ; and this compound substance
may be decomposed or separated into its elementary parts.
Fig. 27, represents a prism, so placed, that a beam of light, admitted by a
small aperture, A, falls upon it, and being refracted is thrown upon the screen
B c, forming an oblong image called the prismatic spectrum, containing the seven
colours already named.
The Raint)OW is formed by the sur^s rays falling upon the upper parts
of the drops of rain, and being then, by refraction, thrown on another part of the
same drop, where they are again refracted and reflected to the eye, so as to pro-
duce the successive colours from the upper part of red, orange, yellow, green,
blue, indigo, and violet (fig. 28).
The Eye Vision- Figs. 29 and 30 represent a front view and a section
of the eye. The eye is composed of three coats or skins, one covering the other.
Within the coverings of the eye-ball are contained three transparent sub-
stances, called humours. These different humours form a compound lens, which
refracts the rays of light rebounding from objects, forming an image of them
upon the retina, the sensation being transmitted by the optic nerve to the brain.
Telescopes- Fig. 31 illustrates the construction and action of a refracting
telescope, and fig. 32, that of a reflecting telescope. The lines show the direc-
tion in which the rays are transmitted through the various lenses.
Fig. 33 represents the camera olscura. This interesting optical instrument
consists of a convex lens A, through which the rays of any objects are admitted
into a darkened chamber, where they fall on a plane mirror B, placed at an angle
of forty-five degrees ; by this they are reflected upwards against a plate of ground
glass c, upon the upper surface of which the objects appear in their natural colours
Fig. 34 represents that well known instrument, the magic lantern.
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ELECTRICITY.
ELECTRICITY is the operation of a subtile fluid, generally invisible, which ap-
pears to be diffused through most bodies.
If a stick of sealing-wax or a watch-glass be rubbed upon a dry piece of
woollen cloth, it will be found, while warm by the friction, that they have
acquired the property of attracting small light bodies, as feathers, &c. Some of
these will adhere to the surface of the wax or glass, and others will be thrown off
from the body, as if they were repelled from it. This phenomenon may be
strikingly exemplified by the small apparatus represented at fig. 1. A, is a stand
with a bent wire, to which, at the hook, B, a fine silk thread is attached, having at
its extremity a small pith ball, c. If the glass rod, 0, be rubbed and presented to
the ball, this will be immediately attracted to the glass, and will remain in con-
tact with it for a few seconds ; if the glass be now withdrawn, and again pre-
sented to the ball, the latter will be repelled (fig. 2). If, instead of the glass, a
piece of sealing-wax, rubbed in the same way, be employed, the same effect is
produced. Both these electrics have, therefore, in the first place, the power of
attracting another body before they have communicated to it any of their own
electricity; and, secondly, having communicated a portion of their electricity,
they repel it. But a very remarkable circumstance takes place, if we, after
having conveyed electricity to the ball, c, by means of excited glass, should pre-
sent to it, after the former was withdrawn, excited sealing-wax : the ball, instead
of being repelled, as it would be were the ball again applied, is attracted by the
wax. If the experiment be reversed, and the excited wax first presented to the
ball, and then the excited glass, the latter will be found to repel the ball. Hence,
we conclude, that there are two opposite electricities ; namely, that produced by
excited glass, to which the name of vitreous, or positive electricity, has been given,
and that produced by excited wax, to which the name of re&inous, or negative
electricity, has been given.
Fig. 3 represents the Cylindrical Electrical Machine, consisting of a hollow
cylinder of polished glass, c c, revolving upon an axis. Two hollow metallic
conductors, D E, are placed parallel to the cylinder on each side, upon two
insulated pillars of glass. To one of these conductors, E, a cushion is attached,
and held close to the cylinder ; from the upper edge of the cushion there proceeds
a flap of oiled silk, which extends over the upper surface of the cylinder to
within an inch of a row of metallic points, proceeding from a hollow rod fixed to
the side of the opposite conductor. When the cylinder is driven round by the
handle, the friction of the cushion upon it produces a transfer of the electric
fluid from the latter to the former ; that is, the cushion becomes negatively, and
the glass positively, electrified. By the revolution of the cylinder, the fluid
adhering to the glass is carried round, and its escape prevented by the silk flap,
until it arrives near to the metallic points, which absorb most of the electricity,
and convey it to the prime conductpr, i>, which thus becomes positively electri-
fied, while the other conductor, having parted with this electricity, is negatively
electrified.
Fig. 4 represents the Plate Electrical Machine. The plate is turned by the
handle through the rubber, which is coated with a metallic amalgam, and
diffuses the excitement over the glass, the points carrying off a constant stream
of positive electricity to the prime conductor, upon the principle already
described.
Fig. 5 represents the Hydro-Electric Machine, an apparatus of recent date
and construction, and of immense power. It consists of a steam boiler, A, in-
sulated on stout glass pillars. The steam is made to issue through a great num.
ber of bent iron tubes, B B, terminating in jets of wood. An insulated projecting
eonductor, c, is placed in connexion with the boiler, for the purpose of col'lecling
the excited electricity ; and another conductor, D, formed of a metallic case
having several rows of points, is placed immediately in front of the jeta, to re-
ceive and carry off the opposite electricity of the steam, and prevent ita return to
the boiler, by which the excited forces would be neutralized. The electricity
thus produced is the result of the friction of condensed particles of water, whilst
teing driven by the still issuing steam through the jets, these watery particles,
performing the office of the glass plate, or. cylinder of the common machine, and
giving out vitreous electricity. The wood jets and pipes act as the rubfcei, and
give out resinous electricity. . ' r ;
ELECTRICITY.
Electricity can be transferred or communicated from one body to another.
An electrified ball can be deprived of its electricity by being touched with a
metallic rod, but if we touch it with glass or wax the electricity will remain
unaffected. Hence, metals are said to be conductors, and glass and wax non-
conductors. Bodies differ greatly in their power of conduction. A list of the
principal substances that possess these properties will be found on the
diagram. The most convenient mode of obtaining an accumulation of elec-
tricity, is by employing a cylindrical glass jar, coated within and without nearly
to the top with tin-foil, and having a cover of baked wood incased with sealing-
wax to exclude moisture and dirt. A metallic rod rising above the jar, and ter-
minating in a brass nob, is made to descend through the cover and communicate
with the interior coating. An apparatus of this kindjs called a Leyden jar, and is
represented at fig. 6.
Fig. 7 represents a discharging rod, for establishing a communication between
the inner and outer coating of the jar. The handle is of glass, to prevent the
operator from receiving the charge of the jar.
By uniting a sufficient number of jars, we are able to accumulate a large
amount of electricity. Such a combination of jars is called an Electrical Battery.
(fig. 8).
Fig. 9 represents an instrument called a Universal Discharger, which is used
for passing charges through any substance that may be laid on plate A.
Fig. 10 represents an Electro-meter, an instrument used to detect the presence
of electricity. If charged, either by placing the instrument on one of the con-
ductors of a machine, or on the rod of an electrical jar, the reed rises and marks
as an index on the graduated semicircle the angle of divergence, by which the
comparative amount of electrification may be estimated. The hairs upon the
well-known electrical toy, represented at fig. 11, are spread out, and stand on end
upon the same principle.
Fig. 12 represents two bells suspended from a brass wire, D i>, supported by
a glass pillar, A. The electricity being conducted to the knob E, passes down
the wires, D D, to the bells, which are then positively electrified, and attract the
clappers, c c, that are negatively so, in consequence of being insulated by silken
strings. The clappers having become charged, strike against the centre bell to
discharge themselves, and thus a peal is rung on the bells till the electricity is
taken off.
Electric sparks are of a bluish colour in the atmosphere in its ordinary state,
und their character depends almost entirely on the form, area, and electrical
intensity of the discharging surfaces. If the small ball, p (fig. 13), be attached to
the prime conductor of a machine, and a larger ball, N, be presented to it, a
series of brilliant sparks, of a crooked or zigzag form, will pass from the smaller to
the larger ball. When, however, electricity is given off from short points, it
is unaccompanied by noise, and presents the brush -like appearance represented
at fig. 14.
The influence of pointed conductors on electrically charged bodies, was first
observed by Franklin, who showed that when presented to them, their charges
became silently and rapidly dissipated. Hence, the utility of pointed conductors
to secure buildings from the effects of lightning (fig. 15).
Galvanism- The production of electricity in this case arises from the cor-
roding action of an acid upon metallic surfaces. The acid being interposed be-
tween two plates of dissimilar metals, usually copper and zinc, and the zinc
being the more oxidable, gives out positive electricity. The two plates are con-
nected together at the top by a wire, and this communciation establishes what is
called a voltaic or galvanic circuit ; the electricity circulating round the zinc,
wire, copper, and liquid (fig. 16).
There are many fortes of galvanic batteries. Fig. 17, represents Daniell's
battery, consisting of a cylinder of copper containing a porous tube, having a
solid rod of amalgamated zinc in its centre. Fig. 18, represents Griffin's im-
proved Smee's battery, consisting of six cells ; the plates are arranged upon a
frame suspanded, by means of a rod and rocket wheel, over the trough con-
twining the exciting liquid. By this arrangement any desired degree of powei
may be obtained by merely raising or depressing the frame.
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CONDUCTORS
.1rnilH)rii in n/'f fi / ni' iln'ir C<>ndut~tihiiitv
iliuii ijj-on.& Mel aJ s in <7'n i rHl,ChnrroalFhiinbiio .fon
ii]iitf-d-A<-Kis.SrtJineS.lutJi
l Flu i/t,/<,,if'/,;/,/
Slidllac.Ajuher, Resins, Sniphm-, Wax. {jr-ass.Viu-i
Minei^Js,Silk> T (Hi].Haii;Featliers.J.f-atJn'r, Air. '
Gases. akH Wood.Drv Vpgetalilc BII-. lMi
Ashes of Animal* and V-srei;it>J- Modif- s Oil
MAGNETISM.
THE theory of magnetism bears a very strong resemblance to that of electri-
city. Like it, magnetism has its attractions and repulsions, and it can be ex-
cited in one body and transferred to another, with, however, this striking pecu-
liarity, that carbonized iron or steel, is nearly the only substance capable of
exhibiting any strong indication of its presence. The loadstone, or natural
magnet (fig. 1), is a hard, dark coloured mineral, found chiefly in iron mines ;
it is, however, seldom used, as its properties can be imparted to bars of steel,
which may be made more powerful than itself.
Fig. 2 illustrates the polarity of the magnet. If a bar or needle, which has
been rendered magnetic, be accurately poised on a point, one of its ends will
point towards the north, and the other towards the south ; hence, those parts of
the magnet are termed the north and south poles.
The reciprocal attractions, repulsions, and neutralizations of the opposite
magnetic forces may be illustrated by straining a piece of paper upon an open
frame, and placing it over a bar magnet (N s, fig. 3). If some iron filings be
now sifted upon the paper screen, the particles will arrange themselves in a series
of curved lines, proceeding from similar points on each side of the- middle of the
bar; others will stand out at the extremities, as if repelled from the poles HT s.
If the opposite poles of two magnets be presented to each other, ati about two
inches distance, and iron dust be projected over them as before, similar results
will ensue. Magnetic lines proceeding from similar points of each bar will
appear uniting the two poles, as represented at fig. 4. If two similar poles be
presented to each other, the lines of force mutually repelling each other, will
present the appearance shown at fig. 5.
Fig. 6 represents the horse-shoe form of magnet, in which the two poles
are brought near together, so as to attract a piece of iron by their combined
force.
The earth itself is found to be a vast magnet, having its two magnetic poles
situated in the neighbourhood of, but at some distance from, its poles of revolu-
tion. ^ This is the reason why magnetized needles point in a north and south
direction, not to the earth's axis (except at certain places), but to the magnetic
poles. This will be seen by reference to fig. 7, which represents compass needles
distributed over the globe, all lying in the direction of lines drawn from one
magnetic pole to the other.
Fig. 8 represents the manner's compass, the most essential part of which is a
magnetized bar of steel, called the needle, accurately poised on a fine central
point within a bowl or case, which is so supported as always to preserve a hori-
zontal position. Upon the needle is placed the circular card represented at
fig.