1 encyclopedia BRITANNICA. VOLUME the SECOND. Encyclopedia Britannica; OR, A DICTIONARY O F ARTS and SCIENCES, COMPILED UPON A NEW PLAN. IN WHICH The different Sciences and Arts are digeffed into diftindt Treaties or Syitems; AND The various TfchnicalTervs, <&c. are expl-aiued as they occur in the order of the Alphabet. ILLUSTRATED WITH ONE HUNDRED AND SIXTY COPPERPLATES. .By Society of GENTLEMEN in Scotland. IN THREE VOLUMES. VOL. If. EDINBURGH: Printed for A. Bell and C. Macfarquhar; And fold by Li o l i n M acf a rq^u h a r, at his Printing-office, Nicolfon-ftreet. M. D C L.L XXL «t22' • J^o % 1365 ^ Encyclopaedia Britannica; Or, A D I C T I O ARTS and S CAB CAABA, or Caabah, properly fignifies a fquare building; but is particularly applied by the Mahometans to the temple of Mecca, built, as they pretend, by Abraham and Ifmael his fon. . It is towards this temple they always turn their faces when they pray, in whatever part of the world they happen to be. This temple enjoys the privilege of an afylum for all forts of criminals; but it is moft remarkable for the pilgrimages made to it by the devout muflulmans, who pay fo great a veneration to it, that they believe a Angle fight of its facred walls, without any particu¬ lar adt of devotion, is as meritorious, in the fight of God, as the molt careful difcharge of one’s duty, for the fpace of a whole year, in any other temple. CAB, an Hebrew dry meafure, being the fixth part of a feah or fatum, and the eighteenth part of an ephah : A cab contained 2^ pints of our corn meafure: A quarter-cab was the meafure of dove’s dung, or more properly a fort of chick-peafe, called by this name, which was fold at Samaria, during the fiege of that city, for five Ihekels. CABALIST, in French commerce, a fadtor, or perfon, who is concerned in managing the trade of another. CABALLARIA, in middle-age writers, lands held by the tenure of furnilhing a horfeman, with fuitable e- quip:ige, in time of war, or when the lord had occa- fion for him. CABALLEROS, or Cavalleros, are Spanilh wools, of which there is a pretty confideraJble trada at Bay¬ onne, in France. CABALLINE denotes fomething belonging to horfes : Thus caballine aloes is fo called, from its being chiefly Voa. II. No. 30. 3 NEW O N A R Y F C I E N C E S. CAB ufed for purging horfes; and common brimftone is cal¬ led fulphur caballinum, for a like reafon. CABBAGE, in botany. See Brassica. CABBAGE-fm-, a name fometimes given to the palm tree, called by Linhasus* phoenix. See Phoenix. CABBAGING, among gardeners, a term ufed for the knitting of cabbages into round heads. CABBALA, according to the Hebrew ftyle, has a very diftindt fignification from that wherein we underftand it in our language. The Hebrew cabbala fignilies tra¬ dition ; and the rabbins, who are called cabbalilts, iiudy principally the combination of particular words, let¬ ters, and numbers, -and by this means pretend to d;l- cover what is to come, and to fee clearly into the fenfe of many difficult pafl'ages in fcripture: There are no fore principles of this knowledge, but it depends up¬ on fome particular traditions of the ancients; for which reafon it is termed cabbala. The cabbalifts have abundance of names, which they call facred: Thefe they make ufe of in invoking of fpirits, and imagine that they receive great light from them: They tell us, that the fecfets of the cabbala were difcovered to Mofes on mount Sinai; and that thefe have been delivered down to them from father to fon, without interruption, and without any ufe of let¬ ters ; for to write them down, is what they are by no means permitted to do. This is likewife termed the oral law, becaufe it pafled from father to fon, in order to diftinguiffi it from the written laws. There is another Cabbala, called artificial, which confilts in fearching for abltrufe and mylieriOus figni- fications of a tvord in fcripture, from whence they borrow certain explanations, by combining the letters A which CAB ( : •which compofe it: this, cabbala is divided into three kinds, the gematrie, the notaricon, and the temura or themurah. The firft whereof confifts in taking the letters of a Hebrew word for ciphers or arithmetical numbers, and explaining every word by the arithmeti¬ cal value of the letters whereof it is compofed. The fecond fort of cabbala, called notaricon, confhts in ta¬ king every particular letter of a word for an entire didion ; and the third, called themurah, i. e. change, confifts in making different tranfpofitions or changes of letters, placing one for the other, or one before the other. Among the OhrffUans likewife, a certain fort of magic is, by miflake, called cabbala, which .confifts in ufing improperly certain paffages of fcripture for magic operations, or in forming magic characters or figures with ftars and talifmans. Some vifionaries, among the Jews, believe, that Jefus Clirift wrought his miracles by virtue of the my- fteries of the cabbala. CABBALISTS, the Jewifh dodors who profefs the ftudy of the cabbala. In the opinion of thefe men, there is not a ■word, letter, or accent in the law, without Tome myftery in it. The Jews are divided into two general feCts ; the karaites, who refufe to receive either tradition or the talmud, or any thing but the pure text of fcripture ; and the rabbinifts, or talmudifts, who, befides this, receive the traditions of the ancients, and follow the talmud. The latter are again divided into two other feCts ; pure rabbinifts, who explain the fcripture, in its na¬ tural fenfe, by grammar, hiftory, and tradition ; and cabbalifts, who, to, difcover hidden myftical fenfes, which they fuppofe God to have couched therein, make ufe of the cabbala, and the myftical methods a- bove mentioned. CABECA, or Cabesse, a name given to the fineft filks in the Eaft- Indies, as thofe from 15 to 20 per cent. inferior to them are called barina. The Indian workmen endeavour to pafs them off one with the o- thcr ; for which reafon, the more experienced Euro¬ pean merchants take care to open the bales, and to examine all the fkains one after another. The Dutch diftinguilh two forts of cabecas ; namely, the moor ea- beca, and the,common cabeca. The former is fold at Amfterdam for about 2 i-I fchellinghen Elemilh, and the other for about lSJ-.. CABENDA, a port-town of Congo, in Africa, and fubjeCl to the Portuguefe : E. long.-12?, and S. lat. 4Q. CABlDOS, .or Cavidqs, a long meafureufed at Goa, and in other places of the Eaft Indies belonging to the Portuguefe, to meafure Huffs, linens, tire, and equal to 4- of the Paris eli. CABIN, in the fea-language, a fmall room, or apart¬ ment, v/hereof there are a great many in fevefal parts of a ftrip ; particularly on the quarter-deck, and on each fide of the fteerage,. for the officers of the fhip to lie in. The great cabin is the chief of all, and that which properly belongs to the captain. or chief commander. ) CAB CABINET, or Cabbinet, the moft retired place in the fineft part of a building, fet apart for writing, ftu- dying, or preferving any thing that is precious. A complete apartment confifts of a hall, anti-cham¬ ber, chamber, and cabinet, with a gallery on one fide. Hence we fay, a cabinet of paintings, curiofities, Cabinet alfo denotes a piece of joiner’s workmanfhip, being a kind of prels or cheft,. with feveral doors and drawers. There are common cabinets of oak or of chefnut, varnifiled cabinets of China and Japan, cabinets of in¬ laid work, and fome of ebony, or the like fcarCe and precious woods.. Formerly the Dutch and German cabinets were much efteemed in France, hut are now quite out of date, as well as the cabinets of ebony, which came from Venice. CABIRI, a term in the theology of the ancient Pagans,. fignifying great and powerful gods j being a name given to the gods of Samothracia. They were alfo worfhipped in other parts of Greece, as 'Lemnos and Thebes, where the cabiria were celebrated in honour of them : thefe gods are faid to be, in number, four, viz. Axieros, Axiocerfa, Axiocerfus, and Cafmilus. CABIRIA, feftivals in honour of the cabiri, celebrated in Thebes and Lemnos, but efpecially in Samothra¬ cia, an ifland confecrated to the cabiri. All who were initiated into the myfteries of thefe gods, were thought; to be fecured thereby from ftorms at fea, and all other dangers. The ceremony of initiation was performed by placing the candidate, crowned with olive-branches, a»d girded about the loins with a purple ribband, on a kind of throne, about which the priefts, and perfons before initiated, danced. CABLAN, the'nan)- of a kingdom and city of India, beyond the Ganges. CABLE, a thick, large, ftrong rope, commonly of hemp, which ferves to keep a fhip at anchor. There is no merchant-ffiip, however weak, but has at leaft three cables ; namely, the chief cable, or cable of the ffieet-anchor, a common cable, and a fmaller one. Cable is alfo faid of ropes, which ferve to raife heavy loads, by the help of cranes, pullies, and other engines. The name of cable is ufually given to fuch as have, at leaft, three inches in diameter ; thofe that are lefs are only called ropes: of different names, ac¬ cording to their ufe. Every cable, of what thicknefs foever it be, is com¬ pofed of three ftrands ; every ftrand of three ropes ; and every rope of three twifts : the twift is made of more or lefs threads, according as the cable is to be thicker or thinner. In the manufafture of cables, after the ropes are made, they ufe ftieks, which they pafs firft between the ropes of which, they make the. ftrands, and after¬ wards between the ftrands of which they make the cable, to the end that they may all twift the better, and be more regularly wound together; and alfo, to prevent them, from twining or intangling, they hang, at CAB ( 3 ) CAB at- the end of each ftrand and of each rope, a weight of lead or of ftone. The number of threads each cable is compofed of is always propoitioned to its length and thicknefs ; and it is by this number of threads that its weight and value are afcertained : thus a cable of three inches circumference, or one inch diameter, ought to confill: of 48 ordinary threads, and weigh 192 pounds; and on this foundation is calculated the following table, very ufeful for all people engaged in marine commerce, who fit out merchant-men for their own account, or freight them for the account of others. A table of the number of threads and ’weight of cables of different circumferences. Circumf. Threads. , Weight. 3 inches. 48 192 pounds 13 16 17 18 19 2P 77 121 174 238 3*i 393 485 598 699 82* 952 1093 *244 14°4 1574 *754 *943 308 484 696 952 1244 1572 1940 2392 2706 3284 3808 4372 4976 5616 6296 7016 7772 Sheet-anchor Ca.-bi.il, is the greatefl cable belonging to a ftiip. Serve or plate the Cable, is to bind it about with ropes, clouts, to keep it from galling in the hawfe. To fplice Cable, is to make two pieces faft together, by working the feveral threads of the- rope, the one into the other. Pay more CkBi.B, is to let more out of the fliip. Pay cheap the cable, is to hand it out apace. ' Veer more cable, is to let more out, tec, CABLED, in heraldry, a term applied to a crofs, formed of the two ends of a ihip’s cable ; fometimes alfo to a crofs covered over with- rounds of rope, more properly called a crofs-corded. Cabl eD-jfa/e, in archite&ure, fuch flutes as are filled up with pieces, in the form of a cable. CABO de Istria, the capital of the province of Iftria, in the dominion of Venice, fituated on the gulph of Venice, about twelve miles fouth of Triefte : E. long, 140 7 3°'-. The ifland it (lands on is in length about eighteen miles; the fouth-weft end is about nine broad, but the other end, where the city Hands, not above two It has a communication with the continent by means of a bridge; and, with the oppofite (bore, forms a bay of twelve miles long and fix broad. About the mid¬ dle of this bay, there are two head-lands, or promon¬ tories, one on the continent, and the other on the ifland, which advance fo near together, that the forts upon them, called the Puntal and Matagorda, com¬ mand the palfage; and within thefe forts is the har¬ bour, which it is impoiTible for an enemy to enter till he has firft taken the forts. CADIZADELITES, a fed of Mahometans very like the ancient ftoics. They ftiun feafts and diverfions, and affeft an extraordinary gravity in all their adions ; they are continually talking of .God, and fome of them make a jumble of Chriftianity and Mahometanifm ; they drink wine, even in the fall of the ramazan; they love and proted the Chriftians 5 they believe that Ma¬ homet is the Holy Ghoft, pradife circumcifion, and jultify it by the example of Jefus Chrift. CADMIA, a metallic fubftance feparated from the ore of zinc by fufion. See Chemistry, Of ziiu. CADORIN, a province of Italy, in the territories of Venice, bounded by the bilhopric of Brixen on the north; C JE M (5 north; by Friuli, on the eaft; by the Bellunefe, on the fouth and by the Trentin, on the weft. CADRITES, a fort of Mahometan friars, who once a-week fpend great part of the night in turning round, holding each other’s hand, and repeating inceflantly the word hat, which fignifies living, and is one of the attributes of God; during which one of them plays on a flute. They never cut their hair, nor cover their heads, and always go barefooted; they have liberty to quit their convent when they pleafe, and to marry. CADSAND, an iljand on the coaft of Dutch Flanders, fituated at the mouth of the Scheld, whereby the Dutch command the navigation of that river. CADUCEUS, in antiquity, Mercury’s rod, or fceptre, being a wand entwifted by two ferpents, borne by that deity, as the enfign of his quality and office, given him, according to the fable, by Apollo, for his feven- . ftringed harp. Wonderful properties are afcribed to this rod by the poets, as laying men afleep, raifing the dead, It is ufed alfo as a fymbol of peace. The caduceus, as found on fome medals, is a common fymbol, figni- fying good conduct, peace, and profperity. CADUS, in antiquity, a wine-veflel of a certain capa¬ city, containing eighty amphorae, or firkins, each of which, according to the beft accounts, held nine gal¬ lons. CALCILIA, in zoology, a genus of ferpents belonging to the amphibia clafs. The caecilia has no fcales; it is fmooth, and moves by means of lateral rugae or prickles. The upper lip is prominent, and furnifhed with two tentacula. It has no tail. There are but two fpecies of this ferpent, viz. i. The tentaculata, has 135 rugae. It is about a foot long and an ipeh in circumference, preferving an uniform cylindrical fhape from the one end to the other. The teeth are very fmall. It has fuch a refemblance to an eel, that it may eafily be miftaken for . one ; but as it has neither fins nor gills, it cannot be clafled with the fifties., It is a native of America, and its bite is not poifonous. 2. The glutinofa has 340 rugae or prickles above and ten below the anus. It is of a brownifh colour, with a white line on the fide, and is a native of the Indies. CiEGUM, or Coecum, in anatomy, the blind-gut. See p. 260. col. 2. CAilMENT, in a general fenfe, any glutinous fubftance, capable of uniting and keeping things together in clofc cohefion: in this fenfe, under caement, are compre¬ hended mortar, folder, glue,, isc. but, ftriftly fpeak- ing, the term caement only denotes a glutinous compo- fition, ufed in caementing broken glafles, china-ware, or earthen-ware. One of the fineft, and at the fame time ftrongeft caement for this purpofe, is the juice of garlic ftamped in a ftone mortar: this, if the operation is done with care, leaves little or no mark. Another caement is made by beating the white of an egg very clear, and mixing with it fine powdered quick-lime : or ifing-glafs, powdered chalk, and a little lime may be mixed toge- Von. II. Numb. 30. 3 ) C iE R ther, and diflblved in fair water. With tbefe, the glaftes, 6c. are to be caemented, and th<-n fet in tl e ftiade to dry; a caution which ftiotftd always be ob- ferved, whichever of the above caements is ufed. A caement for cracked "chemical-giaftes, that will ftand the fire, may be thus prepared : take wheat flour, fine powdered Venice glals, and pulverized chalk, of each an equal quantity ; of fine brick-duft, one half of the faid quantity; and a little fcraped lint: mix them all together with the whites of eggs; then, fpreading this mixture upon a linen cloth, apply it to the cracks of the glafies, which muft be well dried before they are ufed. Old varnifti is another csement that will anfwer the fame purpofe. Cement, among builders, a ftrong fort of mortar, u- fed to bind bricks or ftones together for fome kind of mouldings ; or in cxmenting a block of bricks for the carving of capitals, fcrolls, or the like. There an; two forts, 1. Hot casment, which is the moft commoa, made of refin, bees-wax, brick-duft, and chalk, boiled together. The bricks to be cemented with this kind, muft be made hot with the fire, and rubbed to and fro after the ctement is fpread, in the fame manner as joiners do when they glue two boards together. 2. Cold csement, made of Cheihire-cheefe, milk, quick¬ lime, and whites of eggs.. This csement is lefs ufed than the former, and is accounted a fecret known but to few bricklayers. C/ement, among engravers, jewellers, 6c. a compo- fition of fine brick-duft well fifted, refin, and bees-wax, in ufe among thefe artificers to keep the metals to be engraven or wrought on firm to the block; and alfa to fill up what is to be chefleled. Clement, in chemiftry, a kind of menftruum compound- ed of fairs, fulphurs, and brick, reduced to dry pow¬ ders, and ftrewed betwixt plates of metal, in order to raife their colour, or feparate one metal from another. See Chemistry. Clement-pots, or thofe jufed in the csementation of metals, are made of fine potter’s clay, and that either pure, or mixed with fand in different proportions. CEMENTATION, in a general fenfe, the corroding of metals in a dry form, by means of the fumes of acid falts. See Chemistry, Part II. CAEN, the capital of a county of the fame name in Normandy, fituated on the river Orne, about feventy- five miles well of Rouen, and thirty fouth-weft of Havre de Grace: W. long. 2s', N. lat. 490 20'. It has an univerfity, firft founded by king Henry VI. of England, in 1431. CAERFILLT, a town of Glamorganftiire, about five miles north of Landaff: W. long. 30 1 c' and N. lat. 51° 35'. CAERITES, or C^eritum tabulje, in Roman anti¬ quity, tables or regifters in which the names of the Casrites were regiftered. The people of Csere were accounted dtizens of Rome, hut had no privilege of voting; hence when a Roman citizen was degraded, if a fenator, he was expelled the fenate; if a knight, he loft the public borfe; and if a plebeian, his name was inferted in the regifter of the Casrites; that is, he B was c s ( i was fubjeft to all taxes, but incapable of voting or en¬ joying any public office. CAERLEON, a market-town of Monmouthffiire, fitu- ated on the river Uike, about fixteen miles fouth-weft of Monmouth: W. long. 30, N. lat. 510 4c/. CAERMARTHEN, the capital of Caermarthenffiire in Wales, iituated upon the river Tivy, about five miles from the fea. CAERN ARYAN, the chief town of Caernarvanffiire in Wales, fituated upon the river Menay. CAERWIS, a market town in Flintffiire, in north Wales, about five miles eaft of St Afaph, and four well of Flint: W. long. 30 25', N. lat. 530 20'. C2ESALPINIA, in botany, a genus of the decandria monogynia clafs. The calix has five fegments, the lowed of which is larged; the corolla eonfids of five petals; the capfule is of the pod kind. There are four fpecies, all natives of the Indies. C .ESALPINOIDES, in botany, a fynonime of the gleditfia. See Gleditsia. ■CjESAR, in Roman antiquity, a title borne by all the emperors, fronii Julius Cssfar, to the dedru&ion of the empire. It was alfo ufed as a title of didinftioft, for the intended '6r prefumptive heir of the empire, as King of the Romans is now ufed for that of the Ger¬ man empire. This title took its rife from the furname of the fird emperor, C. Julius Csefar, which, by a decree of the fenate, all the fucceeding emperors were to bear. Un¬ der his fucceflbr, the appellation of Augudus being appropriated to the emperors, in compliment to that prince, the title Caefar was given to the fecond per- ion in the empire, though dill it continued to be gi¬ ven to the fird ; and hence the difference betwixt C«- far ufed Amply, and Caefar with the addition of Ira- perator Augudus. The dignity of Caefar remained the fecond of the empire, till Alexius Comnenus having defied Nice- phorus Meliffehus Caefar, by contradl ; and it being neceffary to confer fome higher dignity on his own brother Ifaacius, he created him Sebadocrator, with the precedency over Meliffenus; ordering, that in all acclamations, &c. Ifaacius Sebadocrator ffiould be named the fecond, and Meliffenus Caefar, the third. CAESARIAN operation, in midwifery. See Mid¬ wifery. •C/E3ARIANS, c^farienfes, in Roman antiquity, were officers or mioiders of the Roman emperors : They kept the account of the revenues of the emperors, and took poffeffion, in their name, of fuch things as de¬ volved, or were cohfifcated to them. GVESTUS, in antiquity, a large gantlet made of raw hide, which the wredlers made ufe of when they fought at the public games. This was a kind of leathern *drap, drengihened with lead, or plates of Iron, which encompaffed the hand, the wrid, and a part of the arm, asi well to de¬ fend thefe parts, as to enforce their blows. Caistus, orCiESTUM, was alfo a kind of girdle, made of wool, which the hufband untied for his fpoufe the drift day of marriage, before they went to bed. ; ) C A G This relates to Venus’s girdle, which Juno borrow*- ed of her, to entice Jupiter to love her. See Ces- tus. CiESURA, in the ancient poetry, is when, in the fcan- ning of a verfe, a word is divided fo, as one part feems cut off, and goes to a different foot from the red:; as, Menti\ri no\li, nun\quam men\dacia\ profunt. where the fyllables ri, li, quatn, and men, are cse- furas. Cassure, in the modern poetry, denotes a red, or paufe, towards the middle of an Alexandrian verfe, by which the voice and pronunciation are aided, and the verfe, as it were, divided into two hemidichs. See Pause. CAFFA, in commerce, painted cotton-cloths manufac¬ tured in the E. Indies, and fold at Bengal. Caffa, or Kaffa, a city and port-town of Crim Tar¬ tary, fituated on the fouth-eall part of that peninfula : E. long. 370, N. lat. 440 55'. It is the mod confiderable town in the country, and fives name to the draits of Caffa, which run from the mxine or Black fea, to the Palus Meotis, or lea of Azoph. CAFFILA, a company of merchants or travellers, who join together in order to go wirh more fecurity thro’ the dominions of the Grand Mogul, ana-through other countries on the continent of the E. Indies. The Caffila differs from a caravan, at lead in Per- fk; for the caffila belongs properly to fome fovereign, or to fome powerful company in Europe ; whereas a caravan is a company of particular merchants, each trading upon his own account. The Engliffi and Dutch have each of them their caffila at Gambron. Caffila on the coad of Guzerat or Cambaya, fignifies a fmall fleet of merchant-ffiips. CAFFRARIA, the country of the Caffers, or Hotten¬ tots, in the mod foutherly part of Africa, lying in the form of a crefcent about the inland country of Mono- motapa, between 35° S. lat. and the tropic of Capri¬ corn ; and bounded on the ead, fouth, and wed, by the Indian and Atlantic oceans, Mod of the fea-coads of this country are fubjetf to the Dutch, who have built a fort near the mod fouthern- promontory, called the Cape of Good-Hope. CAG, or Keg, a barrel or veffel, that contains from - four to five gallons. CAGE, an inclofure made of wire, wickery or the like, interwoven lattice-wife, for the confinement of birds, or wild beads. The cage, in the Roman amphitheatres, was a place wherein favage animals were confined. It was inclofed with iron rails, and open at top, fo as to be feen to the bottom by the fpeflators. CAGLI, a town of the province ofUrbino, in the pope’s* territories, about twenty-five miles fouth of the city ofUrbino: E. long. 140, N. lat. 430 i$'. CAGLIARI, the capital of the ifland of Sardinia, fitu¬ ated on a bay of the fea in the fouthern part of that ifland : E. long. 90 X2,) N. lat. 390. CAGUI, in zoology, a fynonime of two fpecies of mon¬ key, viz. the jaccchus and cedipus. See Simia, CAHERAH, C A I ( CAHERAH, or Al-caherah, the capital of Egypt* which we call Grand Cairo. See Cairo. CAHLO, the name by which fome call the lupus pif- cis or wolf-fiih. CAHORS, the capital of the territory of Querci, in the province of Guienne in France, fituated about forty- five, miles north of Tholoufe: E. long. i°, N. lat. 44° 25/- It is the fee of a bifliop, and has an univerfity. CAHYS, a dry meafure for corn, ufed in fome parts of Spain, particularly at Seville and at Cadiz. It is near a bulhel of our meafure. CAJANABURG, the capital of the province of Caja- nia, or eaft Bothnia in Sweden, fituated on the north- eaft part of the lake Cajania, about three hundred miles north-eaft of Abo : E. long. 270, N. lat. 63° 50'. CAJAZZO, a town of the province of Lavoro in the kingdom of Naples, fituated about fixteen miles north- ealt of the city of Naples: E. long. 15°, N. lat. 4l° 1S'- CAJEPUT, an oil brought from the E. Indies, which refembles that of cardamoms. CAIFUM, a city of China, fituated in the province of Honan, on the river Crocceus, three hundred and fifty miles north-weft of Nanking : E. long. 113° 30/, and N. lat. 350. CAIMACAN, or Caimacam, in the Turkifh affairs, a dignity in the Ottoman empire, anfwering to lieute¬ nant, or rather deputy, among us. There are ufuaily two caimacans, one refiding at Conftantinople, as governor thereof ; the other attend¬ ing the grand vizir, in quality of his lieutenant, fe- cretary of ftate, and firft minifter of his council; and gives audience to ambaffadors. Sometimes there is a third caimacan, who attends the fultan ; whom he acquaints with any public difturbances, and receives his orders concerning them. CAIMAN, or Caiman-islands, certain American iflands lying fouth of Cuba, and north-weft of Ja¬ maica, between 8i° and 86° of W. long, and in 210 of N. lat. They are moft remarkable on account of the fifhery of tortoife, which the people of Jamaica catch here, and carry home alive, keeping them in pens for food, , and killing them as they want them. GAINIANS, or Cainites, in church-hiftory, Chii- ftian heretics, that fprung up about the year 130, and took their name from Cain, whom they looked upon as their head and father : They faid, that he was formed by a celeftial and almighty power, and that A- bel was made but by a weak one. This fefl: adopted all that was impure in the herefy of the gnoftics, and other heretics of thofe times : They acknowledged a power fuperior to that of the Creator ; the former they called Wifdom, the latter. Inferior Virtue : They had a particular veneration for Korah, Abiram, Efau, Lot, the -Sodomites, and e- fpecially Judas, becaufe his treachery occafioned the death of Jefus Chrift: They even made ufe of a go- fpel, which bore that falfe apoftle’s name. GAINITOj in botany. SeeCtfRYSoPHYLLUM. 7 ) CAL CAIRO, or Grand Cairo, the capital of Egypt, fi¬ tuated in a plain at the foot of a mountain, about two miles eaft of the Nile, and 100 miles fouth of the mouth of that river: E. long. 3;0, N. lat. 30°. The town is ten miles in circumference, and full of inhabitants. The caftle ftands on the fummit of a hill, at the fouth end of the town, and is three miles round. The Britifh and other European ftates have their confuls and factors here, for the prote&ion of trade. CAIRO AN, a town of the kingdom of Tunis in A- frica, fituated on the river Magrida, about eighty miles fouth of Tunis : E. long. 90, N. lat. 36<). CAINS, a name given to the Greeks in the ifle of Crete, who revolt from the Turks to the Venetians. CAISSON, in the military art, a wooden cheft, into which feveral bombs are put, and fometimes only fil¬ led with gun-powder : This is buried under fome work whereof the enemy intends to pofftfs themfelves, and,, when they are mafters of it, is fired, in order to blow them up. Caisson is alfo ufed for a wooden frame or cheft, ufed in laying the foundations of the piers of a bridge. CAITHNESS. SccCathness. CAKILE, in botany. See Bunias. CALABA, in botany. See Calophyllum CAL ABAS H-/rvp, in botany. See Crescentia. CALABRIA, the moftToutherly part of the kingdom.: of Naples, fituated over againft Sicily. There are two provinces of Calabria called the Hi¬ ther and Farther Calabria, with refpeft to the city of Naples; Cofenza being the capital of the former, . and Rheggio of the latter. CALADE, in the menage, the defcent or floping decli¬ vity of a rifing menage ground, being a fmall eminence upon which we ride down a horfe feveral times, put¬ ting him to a fliort gallop, with his fore-hams in the air, to make him learn to ply or bend his haunches, . and form his ftop upon the aids of the calves of the • legs, the ftay of the. bridle, and the cavefon feafonably given. CALAHORRA, a city of Old Caftilein Spain, .fituated on the river Ebro, near the confines of Navarre, a- bout fixty miles north-weft of Saragoffa : W. long. . 2°, N. lat. 420 zcx. CALAIS, a port-town of Picardy- in France, fituated on the Englifh channel, about twenty-two miles fouth- eaft of Dover : E. long. 20, N. lat. 51 CALAMANCO, a fort of woolen fluff manufactured in England and in Brabant. It has a fine glofs, and is chequered-in the warp, whence the checks appear on¬ ly on the right fide. Some calamancos are quite plain, others have broad ftripes adorned with flowers; fome with plaimbroad ftripes, fome with narrow itripes, and others watered. CALAMINARIS, or Lapis Calaminaris, in na¬ tural hiftory, a kind of foffd, the general ore of zinc, of a fpungy fubftance and a lax and cavernous tex¬ ture, yet-confiderably-heavy. It is of no determinate lhape or fize, but is found in maffes of a very various and irregular figure. It is, when.. CAL ( S when mod pure and perfeft, of a pale browmfh grey. It is found in Germany, Saxony, Bohemia, and Eng¬ land. See Chemistry, Of zinc. After roafting the calamine, in order to purge it of fulphureous or arfenical matter, it is ufed by phy- ficians in collyria againft defluxions of thin acrid hu¬ mours upon the eyes, for drying up moiflr running ul¬ cers, and healing excoriations. CALAMINT, in botany. See Melissa,'and Men¬ tha. CALAMITA, in natural biftory, a name given to fty- rax. See Sty rax. Calamita is fometimes alfo ufed for the magnet or load-ftone. CALAMITES. See Osteocolla. CALAMUS, in botany, a genus of the hexandria mo- nogynia clafs. The calix has fix leaves; it has no corolla; the berry is imbricated, and contains but one feed. There is but one fpecies, viz. the rotang, a native of India. Calamus aromaticus, or fweet-fcented flag, in the ma¬ teria medica, a fpecies of flag called acorus by Lin- nteus. See Acorus. The root is generally looked upon as a carminative and llomachic medicine, and as fuch is fometimes ufed in pra&ice. Calamus fcriptorius, in antiquity, a reed or rufli to wnte with. The ancients made ufe of ftyles to write on tables covered with wax ; and of reed, or rulh, to write on parchment, or Egyptian paper. CALANGAY, in ornithology. See Psittacu s. CALASH, or Calesh, a light and very low kind of chariot, ufed chiefly for taking the air in parks and gardens. CALASIRIS, in antiquity, a linen tunic fringed at the bottom, and worn by the Egyptians under a white woolen garment; but this lalt they were obliged to pull off when they entered the temples, being only al¬ lowed to appear then in linen habits. CALATAJUD, a city of Aragon, in Spain, fituated on the river Xalo, about fifty miles weft of Saragolfa: W. long. 2° s', N. lat. 410 ij'. CALATHUS, in antiquity, a balket, hamper, or pan¬ nier of ofiers, reeds, or twigs, for women to put their work in, or to gather flowers in. Calathus was alfo a veflel, or pan, for cheefe-curds and milk ; alfo the name of a cup for wine, ufed in facrifices. CALATOR, in antiquity, was a public fcrvant, and a freeman, fuch as a bailiff or crier, a fumner, to fum- mon courts, fynods, and other public aflemblies. CALATRAVA, a city of new Caftile, in Spain, fi¬ tuated on the river Guadiana, forty-five miles fouth of Toledo: W. long. 40 20', N. lat. 390. Knights o/Calatrava, a military order in Spain, in- ftituted under Sancho III. king of Caftile, upon the following occafion. When that prince took the ftrong fort of Calatrava from the moors of Andalufia, he gave it to the templars, who, wanting courage to defend it, returned it him again. Then Don Reymond, of the order of the Ciftercians, accompanied with feveral ) CAL perfons of quality, made an offer to defend the place, which the king thereupon delivered up to them, and inftituted that order. It increafed fo much under the reign of Alphonfus, that the knights defired they might have a grand mafter, which was granted. Ferdinand and Ifabella afterwards, with the confent of pope In¬ nocent VIII. reunited the grand mafterfhip of Cala¬ trava to the Spanifh crown ; fo that the kings of Spain are now become perpetual adminiftrators thereof. The knights of Calatrava bear a crofs gules, fluer- delifed with green, &c. their rule and habit was ori¬ ginally that of the Ciftercians. CALCADA, or St Domingo de Calcada, a city of Old Caftile, in Spain, forty-eight miles eaft of Bur¬ gos : W. long. 30, N. lat. 420 ^(s . CALCANEUM, or os Calc is, in anatomy. See p. 186. col. i. CALCAR, in zoology, the trivial name of a fpecies of nautilus. See Nautilus. Calcar, in glafs-making, a fort of oven, or reverbera¬ tory furnace, in which, being well heated, the cryftal frit, or bollito, is made. Calcar, in geography, a town of the duchy of Cleves, and circle of Weftphalia, in Germany : E. long. 50 5o\ and N. lat. 51° qj'. CALCARIOUS, in general, denotes fomething be¬ longing, to, or partaking of the nature of calx. See Calx. CALCARIUS lapis, in natural hiftory, the fame with lime-ftone. See Lime. CALCEARIUM, in antiquity, a term ufed to denote the allowance made the foldiers to buy their Ihogs. CALCEOLUS, in botany. See Cypripedium. CALCINATION, in chemiftry, the reducing of fub- ftances to a calx by fire. See,Chemistry. CALCITRAPA, and Calqitrapoides, in botany. See Centaurea. CALCULUS, in natural hiftory, properly denotes a little ftone or pebble. See Pebble. Calculus, or calculus humanus, in medicine, the ftone in the bladder or kidneys. See Medicine, and Surgery. Calculus alfo denotes a method of computation, fo called from the calculi, or counters, anciently ufed for this purpofe. Hence, Calculus specialise or literalis, is the fame with algebra. See Algebra. Calculus diffcrentialis is a method of differencing quantities, that is, of finding an infinitely fmall quan¬ tity, which being taken an infinite number of times, fhall be equal to a given quantity. See Fluxions. Calculus among mathematicians, a me¬ thod of differencing exponential quantities, and fum- ming up the differentials of exponential quantities. See Fluxions. Calculus integralis, or summatorius, is a me¬ thod of fumming up differential quanties ; that is, from a differential quantity given, to find the quantity from whofe differencing the given differential refults. See Fluxions. CALDARIUM, in the ancient baths, a certain vault. CAL ( or room, made fo as to colleft the vapours, and pro¬ duce fweating : whence it fignifies a hot houfe, bagnio, ftove, or fweating-room. CALEFACTION, the produftion of heat in- a body from the aftion of fire, or that impulfe impreffed by a hot body upon other bodies about it. This word is ufed in pharmacy, by way of diitindtion from codtion, which implies boiling ; whereas calefa&ion is only heat¬ ing a thing. CALENBURG-CASTLE, the capital of a duchy of the fame name, in Lower Saxony, in Germany, fi- tuated upon the river Leine, about fifteen miles fouth of Hanover : E. long. 90 40', and N. lat. 520 20 . CALENDAR, a diftnbution of time, accommodated to the various ufes of life, but more efpecially fuch as regard civil and eccleliaftical polity. See Astrono¬ my, Of the divijion of time. Julian Chriftian Calendar. See Astronomy, .0/' . the divifion of time. Gregorian Calendar. See Astronomy, Of the di- vifion of time. CALENDER, a machine ufed in manufactories, to prefs certain woollen and filken Huffs, and linens, to make them fmooth, even, and gloffy, or to give them vyaves, or water them, as may be feen in mohairs and tabbies. This inrtrument is compofed of two thick cylinders, or rollers, of very hard and polilhed wood, round which the Huffs to be calendered are wound : thefe rollers are placed crofs-ways between two very thick boards, the lower ferving as a fixed bafe, and the up¬ per moveable, by means of a thick fcrew, with a rope faflened to a fpindle, which makes its axis : the up- permoH board is loaded with large Hones weighing 20000 R>. or more. It is this weight that gives the poliih and makes the waves on the Huffs about the rollers, by means of a fhallow indenture or engraving cut in it. CALENDS, in Roman antiquity, the firfl day of each month, fo called from the Greek [T«/e/«], to pro¬ claim : it being cuHomary, on thofe days, to proclaim the number of holy-days in each month. The Roman method of reckoning the days of their months has foipething extremely Angular in it: in- Head of computing forwards, in the natural order of the numbers 1,2, 3, s/, in botany. See Antirrhinum. CALIACA, a town of Bulgaria, fituated upon the Black-fea, belonging to the Turks. CALIBER, or Caliper, properly denotes the diame-' ter of anybody: thus we fay, two columns of the - fame caliber, the caliber of the bore of a gun, the ca¬ liber of a bullet, itc. Q,K\.\v,Y.v.-compa(fes, the name of an inflrument, made either of wood, iron. Heel, or brafs : that ufed for meafuring buliets confifls of two branches, bending in¬ wards, with a tongue fixed to one of them, ^hd the other graduated in fuch a manner, that if the bullet be compreffed by the ends of the two branches, and the tongue be applied to the graduated branejj, it will fhew the weight of the bullet. Caliber alfo fignifies an inflrument ufed by carpenters, . joiners, and bricklayers, to fee whether their work be well fquared. CALICUT, a town fituated on the Malabar co'afl, in the hither peninfula of India, fubjedt to its o.wn prince : E. long. 750, and N. lat. x i° 20'. This was the firlt port the Portuguefe made in In¬ dia, after failing round the Cape of Good Hope. CALIDUCT, in antiquity, a kind of pipes, or canals, difpofed along the walls of houfes and apartments, ufed, by the ancients, for conveying heat to feveral remote parts of the houfe, from one common furnace. CALIFORNIA. See Callifornia. CALIMUS. See Callimus. CALIN, a compound metal, whereof the C.hinefe make tea-caniflers, and the like. The ingredients feem to be lead and tin. CALIPH, the fupreme ecclefiaflical dignity among the Saracens ; or, as it is otherwife defined, a foveveign dignity among the Mahometans, vefled with abfolute authority in all matters relating both to religion and policy. It. fignifies in the Arabic, fuccefibr or vicar : the Saracen princes affumed this title as -defendants from Mahomet ; the caliphs bearing the fame relation to Mahomet, that the popes pretend they do to Jefus ChriH or St Peter. It is at this day one of the grand fignior’s titles, as fuccefibr of Mahomet 1 and of the fophi of Perfia, as fuccefibr of Ali. CALIPPIC PERIOD, an improvement of the cycle of Mcton, of nineteen years, which Calippus, a famous Grecian aflronomer, finding in reality to contain nine- C teen CAL ( teen of Nabonaffar’s years, four days, and |4|> ^e> to avoid fraflions, quadrupled the golden number, and by that means made a new cycle of feventy-fix years ; which time being expired, be fuppofed the lunation, or changes of the moon, would happen on the fame day of the month, and hour of the day, that they were on feventy-lix years before. CALIX. See Calyx. CALIXTINS, in church-hiftory, a fedt of ChriiTians, in Bohemia and Moravia : the principal point in which they differed from the church, was the ufe of the cha¬ lice, or communicating in both kinds. Caljxtins, is alfo a name given to thofe, among the Lutherans, who follow the fentiments of George Ca- lixtus, a celebrated divine, who oppofed the opinion of St Augulline, on predeftination, grace, and free-will. CALKA, a kingdom of Tartary, in Alia, to the eaft of Siberia. CALKING. See Caulking. CALKINS, the prominent parts at the extremities of a horfe-lhoe, bent downwards, and forged to a fort of point. Calkins are apt to make horfes trip ; they alfo oc- calion blymes, and ruin the back fmev/s. If falhioned in form of a hare’s ear, and the horn of a horfe’s heel be pared a little low, they do little damage.; whereas the great fquare'calkins quite fpoil the foot. Calkins are either fingle or double, that is, at one end of the Ihoe, or at both : thefe laft are deemed lels hurtful, as the horfe can tread more even. .CALL, among hunters, a leffon blown upon the horn, to comfort the hounds. CALLS, natural and artificial, among fowlers, a fport much praftifed during the wooing feafon of partridges, efpecially for taking cock-partridges ; for which they put a hen into a cadge, to call and bring them near. The hen-partridge Ihould be fet near a hedge, in a thin, open, wire-cage, fo that Ihe maybe feen at a good diftance : then the net, called hallier, Ihould be placed quite round the cage, each part about the di- flance of twenty feet: the fowler fhould retire behind the hedge. Artificial Calls are bell made of box, walnut-tree, or the like : they are formed of the' bignefs of an hen’s . egg, bored through from end to end ; about thy mid¬ dle there muft be a hole hollowed, within, to the bot¬ tom ; then have a pipe of a fwan’s quill, and the bone of a cat’s foot, opened at one end, which muft be con¬ veyed into the hole at the end, and fo thruft into the hole at the middle ; take afterwards a goofe-quill, opened at both ends, and put it in at the other end of the call; blow into the quill, and it will make the like noife as the panridge-cock does. CALLA, in botany, a genus of the gynandria polyan- dria clafs. The fpatha is plain ; the fpadix is co¬ vered with flofcules ; it has no corolla ; the berry con¬ tains many feeds. There are three fpecies, none of them natives of Britain. CALLABAS, a town of Indoftan in Afia, upon the road from Surat to Agra. CALLAO, a port-town in a little ifland on the coaft of io ) CAL Peru, in South America, oppofite to Lima: W. lono 76°, and S. lat. 120. CALLEN, a town of Ireland, in the county x>f Kilken¬ ny, and province of Leinfter, about ten miles fouth- weft of Kilkenny : W. long. 7° 22', and N. lat. 52° 25'- CALLICHTYS, in ichthyology, the trivial name of a fpecies of filurus. See Silurus, ' CALLICO, in commerce, a kind of linen manufacture, made of cotton, chiefly in the Eaft Indies, fome of which are painted with various flowers of different co¬ lours ; and others that are never dyed, having a ftripe of gold and filver quite through the piece ; and at each end they fix a tifiue of gold, filver, and filk, inter¬ mixed with flowers. This manufacture is brought hi¬ ther by.the Eaft-India company, and is re-exported by merchants to other parts of Europe. The general wear of ftained or printed India calicoes in this nation having become a general grievance, and occafioning unfpeakable diftrefs upon our own manufacturers, they were prohibited by flat. 7 Geo. I. cap. vii, CALLIDRYS, in ornithology, the trivial name of a ipecies of motacilla. See Motacilla. CALLIFORNIA, a large country of the Weft Indies, lying between 116° and 138° W. long, and between 230 and 46° N. lat. It is uncertain whether it be a peninfula or- an ifland. CALLIGONUM, in botany, a genus of the polyandria digyniaclafs. ’The calix has five leaves ; the petals are four ; it has two ftyli; and the capfule is divided into two partitions, each containing two feeds. There is but one fpecies, viz. the polygonoides, a native of mount Ararat. CALLIGRAPHUS, in antiquity, a copift or fcriviner, who tranfcribed, in a fair hand, what the notaries had taken down in notes, or minutes, being generally in a kind of cypher or fliort-hand, which, as they were in that hand, being underftood by few, were'copied over fair and at length by perfons who had a good hand, for fale, foe. CALLING the houfe, in the Britilh parliament, is the calling over the members names, every one anfwering to his own, and going out of the houfe, in the order in which he is called : this they do, in order to dif- cover whether there be any perfons there not returned by the clerk of the crown ; or if any member be abfent without leave of the houfe. CALLIONYMUS, in ichthyology, a genus of fifties be¬ longing to the order of jugulares. The upper lip is doubled up; the eyes are very near each other ; the membrane of the gills has fix radii; the operculum is fliut ; the body is naked ; and the belly-fins are at a great diftance from each other. There are three fpe¬ cies of callionymus, viz. 1. The lyra, with the firft bone of the back-fin as long as the body of the animal, and a cirrhus at the anus. It is of the Atlantic. 2, The dracunculus, with the firft bone of the bacLfin fhorter than its body ; which is of afpotted yellow co¬ lour. It frequents the (hoies of Genoa and Rome. 3. The indicus, has a fmooth head with longitudinal wrinkles ; the lower jaw is a little longer than the up¬ per CAL ( per one ; the tongae is obtufe and emarginated ; the apertures of the gills are large : it is of a livid colour, and the anus is in the middle of thejjody. It is a1 na¬ tive of Alia. CALLISTEA, in Grecian antiquity, a Leibian feftival, wherein the women ^relented themfelves in Juno’s temple, and the prize was affigned to the faired. There was another of thefe contentions at the fellival of Ceres Eleufinia, among the Parrhalians, and ano¬ ther among the Eleans, where the mod beautiful man was prefented with a complete fuit of krmour, which he confecrated to Minerva, to whofe temple he walk¬ ed in proceflion, being accompanied with his friends, who adorned him with ribbands, and crowned him with a garland of myrtle. CALLOSUM corpus, in anatomy. See p 285. c. 2. CALLUS, or Callosit y, in a general fenfe, any cu¬ taneous, corneous, or ofleous hardnefs, whether na¬ tural or preternatural : but mod frequently it means the callus generated about the edges of a fra&ure, pro¬ vided by nature to prelerve the fradtured bones, or di¬ vided parts, in the fituation in which they are replaced by the furgeon. CALM, in the fea language, is when there is no wind dirring. That tradl of fea, to the northward of the equator, between 40 and io° of latitude, lying between the me- tidians of Cape Verde, and of the eadermod idand of that name, feems to be a place condemned to perpetual calms : the little winds that are being only feme bid¬ den uncertain gabs of very fmall continuance, and lefs extent. The Atlantic ocean, near the equator, is very much fubjett, nay, always attended with thefe calms. CALMAR, the capital of the province of Gothland, in Sweden, fituated on the coad of the Baltic feaj about forty miles north of Carelfcroon : E. long. 160, and N. lat. {6° 40'. CALMUCKS, certain wandering tribes or herds of Tar¬ tars, inhabiting the country north of the Gafpian fea, under the protedion of Ruffia CALNE, a borough-town of Wiltbiire, about twenty miles north of Salilbury, which fends two members to parliament : W. long. 20, and N. lat. 510 gcA CALOGERI, in church-hid'ory, monks of the Greek church, divided into three degrees, the novices, call¬ ed archari; the ordinary profeded, called michroche- mi; and the more perfed, called megalochemi : they are likewife divided into coenobites, anchorets, and reclufes. The coenobites are employed in reciting their office from midnight to fun-fet ; they are obliged to make three genuflexions at the door of the choir, and returning, to bow to the right and to the left, to their brethren. The anchorets retire from the converfation of the world, and live in hermitages, in the neigh¬ bourhood of the monaderiesj they cultivate a little fpot of ground, and never go out but on Sundays and • holy-days, to perform.their devotions at the next mo- nadery. As for the reclufe, they (hut themfelves up in grottos and caverns, on the tops of mountains, which they never go out of, abandoning themfelves. i ) CAL entirely to Providence : They live on the alms fent them by the neighbouring monaderies. -CALOMEL, or dulcified fublimate of mercury, is pre¬ pared in the following manner. Take of corrolive fublimate, one pound; purified quick filver, nine ounces. Having powdered the fublimate, add to it the quick-fdver, and digeb them together in a matrafs, with a gentle fand heat, until they unite ; then increa- fing the heat, let the mixture be fublimed. The fub- limed matter, freed from the acrimonious part at top and fuch mercurial globules as happen to appear di- bin£t in it, is to be reduced into powder, and fubli¬ med again; and this fublimation mud be repeated fix times. This dulcified mercury, or calomel, is one of the bed preparations for general ufe. The dofe, for raifing a falivation, is ten or fifteen grains, taken in the form of a bolus, or pills, every night or oftener, till the ptyalifm begins. As an alterant and diaphore¬ tic, it is given in doles of five or fix grains, a purga¬ tive being oecafionally interpofed, to prevent its afFeid- ing the mouth. It anfwers however much better when given in fmaller quantities, as one, two, or three grains every morning and evening, in cohjun<5t;on with fuch fubdances as determine its adticn to the fkin, as the extra# or relin of guaicum; the patient at the fame time keeping warm, and drinking freely of warm diluting liquors. By this method of managing , it. obdinate, cutaneous, and veneral didempers have been fuccefsfully cured, without any remarkable in-. creafe of the fenfible evacuations. CALOPHYLLUM, 'in botany, a genus of the polyan- dria monogynia clafs. The corolla confids of five pe¬ tals ; the calix has five teeth ; and the drupa is globu- Jar. There are but two ipecies, viz. theinophyUum, and calaba, both natives of India. CALOTTE, a cap or coif of hair, fatin, or other duff: an- ecclefiadicai ornament in mod popiffi- countries. See Cap. Calotte1, in architeflure, a round cavity or depreffure, in form of a cap or cup, lathed and pladered, ufed to diminifh the rife or elevation of a moderate chapel, cabinet, alcove, which, without fuch an expedient, would be too high for other pieces" of the apartment. CALPE, the mountain, at the foot of which, towards the fea, Gibraltar bands. It is half a league in height towards the land, and fo deep, that there is no ap¬ proaching it on that fide. CALQUING, or Calking, a term ufed in painting, • ■ . ys,,,y. \ v ir "■ ' - CAN fluice K are (hut, and the fluice G opened, in order to fill the lock, till the water in the lock, and confequently the veflel, be upon a level with the water in the fu- perior canal D ; as is reprefented in fig. 3. The gate A is then opened, and the veffel pafl’es into the ca¬ nal D. • Again, let it be required to make a veflel defcend from, the canal D, into the inferior canal B. If the lock is empty, as in fig. 2. the gate C and fluice K muft be flint, and the upper fluice G opened, fo that the water in the lock may rife to a level with the water in the upper canal D. Then open the gate A, and let the veflel pafs through into the lock. Shut the gate A and the fluice G: then open the fluice K, till the water in, the lock be on a level with the water in the inferior ca¬ nal ; then the pte C is opened, and the veffel paffes along into the canal B, as was required. It is almoflf needlefs to fpend time in enumerating the many advantages which neceffarily refult from artificial navigations. Their utility is now fo apparent, that molt nations in Europe give the higheft encouragement to un¬ dertakings of this kind where-ever they are pra&icable. The advantages of navigable canals did not efcape the obfervation of the ancients. From the molt early ac¬ counts of fociety we read of attempts to cut through large ifthmufes, in order to make a communication by water, either betwixt different nations, or diftant parts of the fame nation, where land-carriage was long and ex- penfive. Herodotus relates, that the Cnidians, a people of Caria in Afia Minor, defigned to cut the litbmus which joins that Peninfula to the continent; but were fu- perftitious enough to give up the undertaking, becaufe they were interdidled by an oracle. Several Kings of Egypt attempted to join the Red-fea to the Mediterra¬ nean. Cleopatra was exceedingly fond of this project. Soiiman II. emperor of the Turks, employed 50,000 men in this great work. This canal was compleated un¬ der the caliphate of Omar, but was afterwards allowed to falTinto difrepair ; fo that it is now difficult to dif- cover any traces of it. Both the Greeks and Romans intended to make a canal acrofs the Ifthmus of Corinth, which joins the Morea and Achaia, in order to make a navigable paffage by the Ionian fea into the Archipelago. Demetrius, Julius Czfar, Caligula, and Nero, made feveral unfuccefsful efforts to 'open this paffage. But, as the ancients were intirely ignorant of the ufe of wa¬ ter-locks, their whole attention was employed in making level cuts, which is probably the principal reafon why they fo often failed in their attempts. Charlemagne form¬ ed a defign of joining the Rhine and the Danube, in or¬ der to make a communication between the ocean and the Black-fea, by a canal from the river Almutz which dif- charges itfelf into the Danube, to the Reditz, which falls into the Maine, and, this laft falls into the Rhine near Mayence : For this purpofe he employed a prodi¬ gious number of workmen ; but he met with fo many ob- flacles from different quarters, that he was obliged to give up the attempt. The French at prcfent have many fine canals : That of Briare was begun under Henry IV. and finilhed under the diretfion of cardinal PJchelieu in the reign of Lewis Von. II. Numb. 30. -3 17 ) CAN XIII. This canal makes a communication hnwixt ri fe Loire and the Seine by the river Loing. It extends eleven French great leagues from Briare to Montargis. It enters the Loire a little above Briare, and terminates in the Loing at Cepci. There are forty-two locks on this canal. The canal of Orleans, for making another communi¬ cation between the Seine and the Loire, was begun in 1675, and finifhed by Philip of Orleans, regent of France, during the minority of Lewis XV. and is fur- nifhed with twenty locks. It goes by the name of the canal of Orleans ; but it begins at the village of Com- bleux, which is a fmall French league from the town of Orleans. But the greateft and moft ufeful work of this kind is the junflion of the ocean with the Mediterranean by the canal of Languedoc. It vyas propofed in the reigns of Francis I. Henry IV. and was undertaken and finiffied under Lewis XIV. It begins with a iarje refervoir 4000 paces in circumference, and 24 feet deep, which receives many fprings from the mountain Noire. This canal is about 64 leagues in length, is fup- -plied by a number of rivulets, and is furniffied with 104 locks, of about, eight feet rife each. In feme places it paffes over bridges of vaft height; and in others it cuts through folid rocks for 1000 paces. At one end it joins the river Garonne near Tholoufe, and terminates at the other in the lake Tau, which extends to the port of Cette. It was. planned by Francis Riquet in the 1 666, and fi- niflted before his death, which happened in the 1680. In the Dutch, Auflrian, and French Netherlands, there is a very great number of canals; that from Bruges to Offend carries veffcls of 200 tons. The Chincfe have alfo a great number of canals ; that which runs from Canton to Pekin, extends about 825 miles in length, and was execute about 800 years ago. • It would be an endlefs talk to deferibe the numberkfs canals in Holland, Ruflia, Germany, i&c. We lhall therefore confine ourfelves to thofe that are either already finiffied, or at prefent executing in our own country. As the promoting of commerce is the principal intention of making canals, it is natural to expect that their fre¬ quency in any nation ffiould bear fome proportion to the trade carried on in it, providing the fituation of the country will admit of them. The prefent ffate of Eng?- land and Scotland confirms this obfervation. Though the Romans made a canal between the Nyne, a little be¬ low Peterborough, and the Witham, three miles below Lincoln, which is now almoff entirely filled up, yet it is not long fince canals were revived in England. They are now however become very* numerous, particularly in the counties, of York, Lincoln, and Chefhire. Molt of the counties betwixt the mouth of the Thames and the Briftol channel are conne&ed together either by natural or artificial navigations ;. thofe upon the Thames and Ifis reaching within about, twenty miles of thofe upon the Severn. The jluke cf Bridgewater’s canal in Chelhire . runs twenty-feven miles on a perfect level ; but at Barton it is carried by a very high aqueduft bridge.over the Tr- well, a navigable river; fo that it is common for vefleis to be paffing at the fame time both under and above the E , bridge. ( CAN - ( bridge. It is likewife cut fome miles into the hills, where the Duke’s coal mmes are wrought. Though a navigable communication between the rivers Forth and Clyde in Scotland had been long talked of, it was never conlidered with a view to execution till the year 1761, when the ground was furveyed by Mr Smea- ton, at the defil e of the trullees for fisheries and manu- fadhtres in Scotland. From Mr Smeaton’s furvey and report, the practicability of this canal was fully demon- ftrated. But, after the fcheme became an objedt of ge¬ neral attention, it was found that a canal of larger di- menfions than the one originally propofed would be pro¬ ductive of ftiil greater advantages to the nation. Mr Smeaton was therefore directed to make a fecond fufvey, and to report to the intended proprietors an eftimate of the expence of making a canal 24 feet broad at bottom, 54 at top, containing feven feet deep of water, and ex¬ tending From the Forth to the Clyde, a diftance of about 31 miles, with a collateral branch to the town of Glaf- gow, which is about fix miles, and another from Bains- ford to the river Carron below Carron-works, making in all about 37 miles. _ This report was approved of, an afl: pf parliament was obtained, and the canal is now cut¬ ting upon this very plan. It begins at the Holemerrie in the mouth of the Carron, and terminates at Dam- muir-burn-fbot on the river Clyde, about feven miles be¬ low Glafgow. Above feven miles are already cut, from the Holemerrie weftward; a number of hands are like¬ wife employed at the point of partition in Dollater-bog, and the whole is expeCled to be finifhed in five years. At the point of partition, which is l168 feet above the level of the fea at low water, a very large refervoir is to be made for fupplying the canal; and the veffels are to be raifed and lowered by means of 41 locks. Where the courfe of the cafnal is interfe&ed by burns or ri¬ vers, it is to be carried over them by aqueduCl-bridges ; three of thefe bridges will-be large, and require con- fiderable labour and expence, viz. one over the Grange- burn, one over Bony-mill-burn, and a third over the Kelvin.in the Glafgow branch. The expence of execu¬ ting the whole is computed to be about 150,000 1. Sea-vefiels, about 20 feet wide and 60 feet long, and carrying 70 or 80 tons, may pafs along by this canal from the one frith to the other. But it will admit a free paffage to veffels of 140 tons, provided they be built in the manner of the flat veflels ufed by the Dutch. The toll-duty, allowed by the aft of parliament, is not to exceed 2 d. a ten per mile. Privileged goods, fuch as lime and lime-ftone, are to pay only one third of the ufual toll-duty; ftones, gravel, and other materials for making or repairing roads, likewife dung, foil, marie, and all forts of manure, are exempted from paying any toll-duty,. provided they do not pafs any lock but when the water {hall flow over the place made for difchargmg the overplus-water in the canal. We muft not conclude this article without obferving, that in Ireland alfo the utility of artificial navigations has not been unattended to. Several canals are there making; in particu¬ lar, one froro-Loch-Neach toNewry, about 20 miles; and another from the river Shannon to Dublin, about 70 miles. 18 ) CAN Canal, in anatomy, a duft or pafiage through which any of the juices flow. CANARIES, iflands, to the number of feven, fituated in the-^tlantic ocean, between 120 2I7 W. long, and between 27° and 290 N. lat. the mofl: eafterly of them lying about 150 miles from Cape Non, on the coafl: of Biledulgerid, in Africa. CANARY, properly fo called, is a confiderable ifiand, about 150 miles in circumference ; the chief town of which is Palma, from whence comes the excellent palm-fack, and other rich wines. It lies in 160 W. long, and between 27° and 28° N. lat. Canary-£/W. See Fringilla. CANCALE, a fmall town of France, near St Malo’s, where {hips may ride in eight fathoms water, with a fandy bottom. CANCELIER, in falconry, is when a light-brown hawk, in her {looping, turns two or three times upon the wing, to recover herfelf, before flie feizes. CANCELLI, a term ufed to denote lattice-windows, or thofe made of crofs-bars, difpofed lattice-wife ; it is alfo ufed for rails or ballufters, inclofing the com¬ munion-table, a court of juftice, and the like, and for the net-work in the inlide of hollow bones. CANCER, or Crab, in zoology, a genus of infefts be¬ longing to the order of infefta aptera. The generic charafters are thefe : They have eight legs, (feldom ten or fix), befides the two large claws'Which anfwer the purpole of hands. They have two eyes at a con¬ fiderable diftance from each other, and for the moft part fupported by a kind of pedunculi or foot-ftalks; the eyes are likewife elongated and moveable. They have two clawed palpi ; and the tail is jointed. There are no lefs than 87 fpecies of Cancer, diftinguiflted principally by the length af their tails and the margins of their breafts. This genus includes the lobfteri; flirimp, &c. Cancer, in medicine, a roundifti, unequal, hard, and livid tumour, generally feared in the glandulous parts of the body, fuppofed to be fo called, becaufe it ap¬ pears at length, with turgid veins {hooting out from it, fo as to referable, as it is thought, the figure of a crab-fifli; or, as others fay, becaufe, like that filh, where it has once got, it is fcarce poflible to drive it- away. See Medicine, and Surgery. Cancer, in aftronomy, one of the twelve figns of the zodiac, reprefented on the globe in the form of a crab,' and thus marked (25) in books. 7>0/>& Cancer, in aftronomy, a lefler circle of the fphere parallel to the equator, andpaffing through the beginning of the fign cancer. CANCHERIZANTE, or Cancherizato, in the Italian mufic, a term fignifying a piece of mafic that begins at the end, being-the retrograde motion from* the end of a fong, CANETO, a fortified town of the duchy of Mantua, fituated on the OgHo, about twelve miles fouth-weft of Mantua: E. long. io° 50', N. lat. 45°. GANG, a gulf or fea, lying between China and Tarta¬ ry, at the eaft end of the long wall. CANICULA, in ichthyology, the trivial name of a fpe- cies of fqualus. See S^italus. 1 CANICULA, or Caniculus, in aftronomy. See A- stronomy, OffixedJiars. / It is alfo a name given to dne of the ftars of the conftellation cam's major, called, the dog-ftar, and by the Greeks, firius. CANICULAR days, commonly called dog-days, a cer¬ tain number of days preceding and enfuing the heliacal raifing of canicula, or the dog-ftar, in the morning. The Ethiopians-and Egyptians began their year at the rifing of the dog-ftar, reckoning to its rife again the next year, which is callecbthe annus canarins. The Romans fuppofed it to be the caufe of the fultry wea¬ ther ufually felt in the dog-days; and therefore facrificed abrown dog every year at its rifing, to appeafe its wrath. The dog-days begin towards the end of July, and end the beginning of September. CANINE/whatever partakes of, or has any relation with the nature of a dog,- Thus, Canine teeth, are twofharp-edged teeth in each jaw; one on ea"h fide, placed between the incifores and molares. •CANTS, or Dog, in zoology, a.genas of quadrupeds, ■Vox. II. No. 3-1. 3 i ) CAN belonging to the order of ferae. The chara&ers of the dog are thefe: He has fix fore-teeth in the upper jawi thofe in the fides being longer than the inter¬ mediate ones, which are lobated; in the under jaw there are likewife fix fore-teeth, thofe on the fides being lobated. He has fix.grinders in the upper, and feven in the lower jaw. The teeth called dog-teeth are four, one on each fide, both in the lower and upper jaw; they are iharp-pointed, bent a little inward, and Hand at a diftknce from any of the reft. There are nine fpecies of this genus,, viz. 1. The famili- aris, of domeftic dog, is diftinguilhed from the other fpecies, by having his tail bent to the left fide ; which mark is fo fingular, that perhaps the tail of no other quadruped is bent in this manner. Of this fpeyies there are a great number of varieties. Linnaeus enumerates eleven, ami Bouffon gives figures of no lefs than twenty-feven, viz. . the molofi’us, or maftiff, which is about the fize of a wolf, with the fides of the lips hanging down, and a full robuft body. The large Danifti dog, differs only from the former in being fuller in the body, and generally cf a larger fize. The grey-hound is likewife the fame with the maftiff; but its make is more (lender and delicate. Indeed the difference betwixt thefe three dogs, although perfe&ly diftinguifhable at firft fight, is not greater than that betwixt a Dutchman, a Frenchman, and an Italian. The fhepherd’s dog, the wolf-dog, and what is common¬ ly called the Siberian dog, to which may be joined the Lapland dog,, the Canada dog, and, in general, all thofe which have ftrait ears and a pointed fnout, are all one kind, differing only in thicknefs, the roughnefs or fmooth- nefs of their ikin, the length of their legs, and tails. The hound, or beagle, the terrier, the braque, or ftrort-tailed fetting-dog, and the fpaniel, may be confidered as the fame kind : they have the fame form and die fame in- ftin&s ; and differ only in the length of their legs, and fize of their ears, which in each of them .are long, foft, and pendulous. The bull-dog, the fmail Danilh dog, the Turkifh dog, and the Iceland dog, may likewife be confideted as the fame kind, all the varieties in their ap¬ pearance taking their rife merely from climate. For in- ftance, the Turkilh dog, which has no hair, is nothing elfe but the fmail Danilh dog tranfported to a warm climate, which makes the hair fall off. A dog of any kind lofes its hair in very warm climates. But this is not the only change which arifes from difference of cli¬ mate. In fome countries, the voice is changed-; in 0- thers, dogs become altogether filent. In fome climates, they lofe the faculty of barking, and howl like wolves, or yelp like foxes. Warm climates even change their form and inftimSs: They turn ill-fhaped, and their ears be¬ come ftrait and pointed. It is only in temperate climes that dogs preferve their natural courage, ardour, and fagacity. In order to give an idea of the different kinds of dogs, in different climates, and of the varieties produced by commixtures, we lhall give an explanation of Bouffon’s genealogical tree. See Plate LXI. fig. 1. This tree is conftnnfted ih the form of a geographical chart, in which the fituation of the different climates to which the parti- F cular CAN (2 cular dogs Belong, is obferved as accurately as the na¬ ture of the thing will admit. The Ihepherd’s dog is the flump of the tree. This dog, when tranfported to. Lapland, or any very cold cli¬ mate, affumes an ugly: appearance, and its legs become ihort. But. in Britain, Raffia, Siberia, fyc. where'the •cold is not fo rigorous, and the people are more civili¬ zed, he arrives at greater perfe<5!ion, Both in form and iagacity. The fame fhepherd’s dog,- when brought up in a country fully civilized,. as Britain or France, lofes his •fivage air, his flrait ears, his thick-long hair, and becomes what is cajled a bull-dog, a maftifr, a beagle, or hound, T’hefe changes, Bouffon attributes to the influence of the climate, the manners of the people, forgery, a tube made of different me¬ tals, principally of filver and lead, but fometimes of iron. They are introduced into hollow ulcers, in order to facilitate a difcharge. of pus or any other fubftanCe ; or into wounds,, either accidental or artificial, of the large cavities, as the thorax or abdomen: they are tiled in the operation of branchotomy, and by iome, after cutting for the (lone, as a drain for the urine. Other cannulas are ufed for introducing cauteries, either a&ual or potential, in hollow parts, in order to guard the parts adjacent to that to be cauterifed, from injury. They are of various figures j fome being oval, feme round, and others crooked. CANOE, a fmall boat, made of the trunk of a tree, bored hollow j, and fometimes alfo of pieces of bark fewed together. It is ufed by the natives of America to go a-filhing in the fea, or upon fome other expedition, either by lea, or upon the rivers and lakes. CANON, commonly called prebendary, a perfon who poffeffes a prebend, or revenue allotted for the per¬ formance of divine fervice in a cathedral or collegiate church. Originally, canons were only priells, or in¬ ferior ecclefiauics, who lived in community, refiding near the cathedral church to affift the hiihop, depend¬ ing entirely on his will, fuppotted by the revenues of his biftiopric, and living in the fame houfe as his do- meftics or counfellors, It gives the title of earl to the no¬ ble family of Brudenel, and fends only one member to parliament. CARDINAL, in a general fenfe, an appellation given to things on account of their prehemintnee: thus we fay, cardinal virtues, 6c. Cardinal signs in the zodiac, are Aries, Libra, 'Cancer, and Capricorn. Cardinal, more particularly fignifies an ecclefiaftical prince in the Romilh church, being one who has a voice in the conclave at the-election of a pope. The cardinals were originally nothing more than deacons, to whom was intrufted the care of diftributing the alms to the poor of the feveral quarters of Rome; and as they held aflembiies of the poor in certain churches of their feveral diftridts, they took the title of thefe churches. They began to be called cardinals in the year 300, during the pontificate of St Sylveft- er, by which appellation was meant the chief priefts -of a parilh, and next in dignity to a bilhop. This office grew more conftderable afterwards, and by fmall degrees arrived at its prefent height, in which it is the reward of fuch as have ferved his holinefs well, even princes thinking it no diminution of their honour to become members of the college of cardinals. The cardinals compofe the pope’s council, and, till the time of Urban VIII. were ftyled nioji illujlrious ; but by a decree of that pope in 1630, they had the title of eminence conferred upon them. At the creation of a new cardinal, the pope per¬ forms the'ceremony of fnutting and opening his mouth, which is done in a private ccnfiftory. The (hutting his mouth, implies the depriving him of the liberty of giving his opinion in congregations ; aud the opening his mouth, which is performed fifteen days after, fig¬ nifies the taking off this reftraint. However, if the pope happens to die during the time a cardinal’s mouth is (hut, he can neither give his voice in the eledtiou of a new pope, nor be himfelf advanced to that dig¬ nity.. The cardinals are divided into fix clafles or orders, confifting of fix bifnops, fifty priefts, and fourteen deacons, making in all feventy*; whic h conftitute the facred college. The number of cardinal-bifliops has very feldom been changed, but that of priefts and dea¬ cons have varied at differen: times. The privileges of the cardinals are very great: They have an abfolute power in the church during the vacancy of the holy fee: They have a right to tied the new pope, and. are the only perfons on whom the choice can fall: Moft of the grand offices in the court of Rome are filled by cardinals. The drefs of a cardinal is a red foutanne, a rochet,, a.fhort purple mantle, and the red hat. When they, are lent to the courts of princes, it is in quality of legates « Aj/tw,- and when they are appointed governors of towns, their government is called by the name of legation. Cardinal is alfo a title given to fome bilhops, as thofe of Mentz and Milan, to the archbifhop of Bourges ; and the abbot of Vendome Calls, himfilf cardinalis natus. Cardinal’s flower. See Rapuntium. CARDIOlD, in the higher geometry, an algebraical curve, fo called from its refeiiblance to a heart. CARDIOSe CAR ( ) CAR CARDIOSPERMUM, in botany, a genus of the 6c- tandria trigynia clais. The calix has four leaves; there are four petals; an unequal four-leaved nedfan- um; and there are three inflated capfules. There are two fpecies, both natives of the Indies. CARDIUM, in zoology, a genus of infetts belonging to the older of vermes teflacea. The fhell confilts of two equ;d valves, and the fides are equal. There are 21 fpecies of this genus. CARDONNA, a city of Catalonia, in Spain, fituated on a river of the fame name, about forty miles north- weft of Barcelona : E. long. i° 2o\ N. lat. 410 35'. CARDUEL, a province of Georgia, in Alia, lying be¬ tween the Cafpian and Euxinefeas, the capital where¬ of is Teflis. It belongs partly to the Turks, and partly to the Perfians. CARDUELIS, in ornithology, a fynonime of a fpecies of fringilla. See Fringilla. CARDUUS, in botany, a genus of the fyngenefia poly- gamia aequalis clafs. The calix is ovated, and im¬ bricated with fpinous fcales; and the receptacle is hairy. There are 26 fpecies, ten of which are na¬ tives of Britain, viz. the lanceolatus, or fpear-thiftle; the nutans, or mufk-thiftle; the acanthoides, or welted- thiftle ; the crifpus, or thiftle upon thiftle; the palu- ftris, or marfh-thiftle ; the difie&us, orEnglilh foft thi- ftb ; the helenioides, or melancholy thiftle; the maria- nus, or milk-thiftle; and the acaulos, or dwarf carline- thiftle. CAREENING, in the fea-language, the bringing a fhip to lie down on one lide, in order to trim and caulk the other fide. A fhip is faid to be brought to the careen, when the moft of her lading being taken out, (he is hailed down on one fide by a fmall veffel as low as neceffary; and there kept by the weight of the ballaft, ordnance, as well as by ropes, left her marts fhould be {trained too much ; in order that her fides and bottom may be trimmed, feams caulked, or any thing that is faulty under water mended. Hence when a fhip lies on one fide when fhe fails, fhe is faid to fail on the careen. Carelia, in geography, a province of Finland, bound¬ ed by the province of Savolaxia on the north, and by the gulph of Finland on the fouth. It is fubjedt to Rufiia. CARELSCROON, a port-town of the province of Gothland, in Sweden, fituated on the coaft of the Baltic: E. long. 150, and N. lat. 56° 20 . It is an excellent harbour, where the Swedes lay up their royal navy. CARENTAN, a town of Normandy, in France, fitua¬ ted at the mouth of a river of the fame name: W. long. i° 15', and N. lat. 490 20 . CARET, among grammarians, a character marked thus a, fignifying that fomething is added on the margin, or interlined, which ought to have come in where the caret ftands. CARETTA, in zoology, the trivial name of a fpecies of teftudo. SccTestudo. CAREX, in botany, a genus of the moncecia triandria clais. The amentum of the male is imbricated; it has no corolla; and the calix confifts of one leaf. The amentum of the female is likewife imbricated ; the co¬ rolla is wanting ; and the calix confifts of one leaf; the nedtarium is inflated and three-teethed; there are three ftigmata ; and the feeds are triangular and con¬ tained within the nedlarium. There are 37 fpecies, 26 of which are natives of Britain. CARGADORS, a name which the Dutch give to thofe brokers, whofe bufinefs is to find freight for ihips out¬ ward bound, and to give notice to the merchants, who have commodities to fend by fea, of the {hips that are ready to fail, and of the places for which they are bound. CARGAPOL, or Kargapol, the capital of a terri¬ tory of the fame name, in the province of Dwina, in Mufcovy: E. long. 36°, and N. lat. 63°. CARGO denotes all the merchandifes and effedts which are laden on board a Ihip. Super-ChKGo, a perfon employed by merchants to go a voyage, and overfee the cargo, and difpofe of it to the beft advantage. CARIAMA, in ornithology, a fynonime of the palame- dea. See Palamedea. CARIBBE-islands, a clufter of iflands, fituated in the Atlantic ocean, between 590 and 63°, W. long, and between 110 and 180 N. lat. They belong part¬ ly to the Britifti, and partly to the French, Dutch, CAROLUS, an ancient Englifh broad piece of gold, druck. under Charles I. its value has of late been at twenty-three fhiliings derling, though at the time it was coined, it is faid to have been rated at twenty fhillings. Car onus, a fmall copper coin, with a little filver mix¬ ed with it, druck under Charles VIII. of France. The carolus was worth twelve deniers, when it cea- fed to be current. Thofe which are dill current in trade, in Lorrain, or in feme neighbouring provinces, go under, the name of French fols. CAROTID arteries, in anatomy. See p. 226. CARP, in ichthyology, the Englifh name of a fpecies of cyprinus. SeeCypRiMus. CARPENTRY, the art of cutting, framing, and join¬ ing large pieces of wood, for the ufes of building. It is one of the arts fubfervient to architefture, and is divided into houfe-carpentry and fhip-carpentry: The firdis employed in railing roofing, flooring of houfes;6^c. and the fecond in the building of fhips, barges, &c. The rules in carpentry are much the fame with thpfe of joinery; the only difference is, that carpentry is ufed in the larger coarfer work, and joinery in the fmaller and curious. See Joinery. CARPET, a fort of covering of duff, or other materi¬ als, wrought with the needle or on a loom, which is part of the furniture of ahoufe, and commonly fpread over tables, or laid upon the floor. Perfian CAR ( Perfian andTurkey carpets are thofe moil: efleemed; though at Paris there is a manufactory after the manner of Perfia, where they make them littfe inferior, not to lay finer, than the true Perfian carpets. They are velvety, and perfectly imitate the carpets which come from the Levant. There are alfo carpets of Germany, forne of which are made of woollen fluffs, as ferges, &c. and called fquare carpets: Others are made of wool alfo, but wrought with the needle, and pretty often embellilhed with filk; and laflly, there are car¬ pets made of ddg's hair. We have likewife carpets made in England, which are uied either as floor- carpets, or to make chairs and other houlehold furni¬ ture : It is true, we are not arrived at the like per¬ fection in this manufacture with our neighbours the French; but may not this be owing to the want of the like public encouragement? CAllPI, a town of the Veronefe in Italy, fituated on the river Adige, twenty four miles fouth-eaft of Vero¬ na : E. long ii° 40r, and N. lat. 450 ic/. • Cx^R-PINUS, the Horn-bean, in botany, a genus of the monoecia polyandria clafs. The calix of the male is bell-fhaped, and divided into five fegments ; it has no corolla ; and the (lamina are ten. The calix of the female has four teeth ; there is no corolla; the ftyli are three; and the capfule has four valves, con¬ taining two feeds. There are but two fpecies, both natives of America. CARPIO, in ichthyology, the trivial name of a fpecies of falmo and cyprinus. See Salmo, and Cyprinus. CARPOBALSAM, in the materia medica, the fruit of the tree which yields the true oriental balfam. The caprobalfam is ufed in Egypt, according to Profper Alpinus, in all the intentions for which the balfam itfelf is applied: But the only ufe the Euro-^ peans make of it is in venice-treacle and mithridate, and in thefe not a great deal; for cubebs and juniper- berries are generally fubftituted in its place. CARPOBOLUS, in botany. See Lycoperdon. CARPUS, the Wrist, in anatomy. Seep.-179, 180. CARR, among the ancients, a kind of throne mounted on wheels, and ufed in triumphs and other folemn ocr cafions. CARRIAGE, a vehicle ferving to convey perfons, goods, merchandifes, and other things from one place to an¬ other. For the conflruClion and mechanical principles of wheel-carriages, fee Mechanics. Carriage of a cannon, the frame or timber-work on which it is mounted, ferving to point it. for (hooting, or to carry it from one place to another. It is made of two planks of wood, commonly one half the length of the gun, called the cheeks, and joined by three wooden tranfums, llrengthened with three bolts of iron. It is mounted on two wheels; but on a march has two fore-wheels, with limbers added. The prin¬ cipal parts of a carriage are the cheeks, tranfums, . bolts, plates, train, bands, bridge, bed, hooks, tru- nion-holes, and capfquare.. 2?/<3c-LCarriage, a cart made on purpofe for carrying • mortars and their beds from place to place, 39 ) CAR TVaci-CARRiAGE, two fliort planks of wood fupported on two axle-trees, having four trucks of folid wood for carrying mortars or guns upon battery, where their own carriages cannot go. They are drawn by men. CARRICK, the mod foutherly divifion of the (hire of Air in Scotland. Carrick on the Sure, a town of Ireland, in the county of Tipperary, and province of Munder, about four¬ teen miles north-wed of Waterford: W. long. 70 24, and N. lat. 520 16'. Carrick-fergus, a town in the county of Antrim, and province of Ulder, in Ireland, about eighty-five miles north of Dublin : W. long. 6° ij', and N. lat. 5Ag 4f'- CARROT, in botany. See Daucus. fftfrti'/y-CARROT. SeeMYRRHIS. Z)eW/y-CARROT. See Thapsia. Mountain Carrot. See Foeniculum. CARROUSAL, a courfe of horfes and chariots, ora magnificent entertainment exhibited by princes on fome public rejoicing. It confids in a cavalcade of feveral gentlemen richly dreffed and equipped, after the man¬ ner of ancient cavaliers divided into fquadrons, meet¬ ing in fome public place,, and prafliling jails, tourna¬ ments, CAR ( , ciple, in regard, extenfion being implied in the idea of ipace, matter is lb too. Upon thefe principles, the Cartefians explain me¬ chanically, and according to the laws of motion, how the world .was formed, .and whence the prefent appear¬ ances of nature do rife. They fuppofe, that matter was created of an indefinite extenfion, and divided into little fquare mafleS, full of angles ; that the Creator impreffed two motions on this matter; one whereby each part revolved round its centre, another whereby an aflemblage, or fyftem, turned round a common cen¬ tre ; whence arofe as many different vortices as there were different maffes of matter, thus moving round common centres. The confequences of this hypothefis, according to the Cartefians, will be, that the parts of matter in each vortex could not revolve among each other, with¬ out having their angles gradually broken, and that this continual fridtion of parts and angles produced three elements; the firft, an infinitely fine dull, formed of the angles broken off; the fecond, the fpheres re¬ maining, after all the angular irregularities are thus removed : ,thefe twq make the matter of Des Cartes’s firft and fecond element; and thofe particles not yet rendered fmooth and fpherical, and which ftill retain fome of their angles, m ike the third element. Now, according to the laws.of motion, the fubtileft element mult take up the centre of each fyftem, being that which conftitutes the fun, the fixed ftars above, and the fire below ; the' fecond element, compofed of fpheres, makes the atmofphere, and all the matter be¬ tween the earth and the fixed ftars, in fuch a manner as that the largeft fpheres are always next the circum¬ ference of the vortex or fyftem, and the fmalleft next its centre ; the third element, or the hooked particles, is the matter that compofes the earth, all terreftrial bodies, comets, fpots in the fun, trope which borrows the name of one thing to exprefs another. Thus Milton defcrtbing Raphael’s defcent from the empyreal heaven to paradife, fays, “ Down thither prone in flight “ He fpeeds, and thro’ the vafl: etherial flty “ Sails between worlds and worlds.” CATACOMB, a grotto or fubterraneous place for the burial of the dead. The term is particularly ufed in Italy, for a vaft aflemblage of fubterraneous fepulchres, three leagues from Rome, in the' via Appia, fuppofed to be the fe¬ pulchres of the ancients: Others imagine t-hefe cata¬ combs to be the cells wherein the primitive Chriflians hid themfelves. - Each catacomb is three feet broad, and eight or ten high, running in form of an alley or gallery, and communicating with one another. CATAGMATIC3, in pharmacy, remedies proper for curing a catagma or fradture. CATALEPSY, in medicine. See Medicine. CATALONIA, a province of Spain, bounded by the Pyrenean mountains which divide it from France, on the north ; by the Mediterranean, on the eaft and Toiith ; and by the provinces of Aragon and Valencia, j>x\ the weft. CATAMENIA, in medicine. See Menses. CATAMI1 E, a boy kept for fodomitical pradtices. CATANANCHE, in botany, a genus of plants belong- 'ing to the fyngenefla polygamia eequalis clafs. The Vol. II. No. 32. 3 . 5 ) CAT receptacle'is paleaceous; 'the calix is imbricated ; and the pappus has an awn, with a kind of cet-aceous calix. There are three Ipecies, none of which are natives of Britain. CATAPASM, among ancient phyficians, fignifies any dry medicine reduced to powder, in order to be ufed by way of infpiration in the whole body, or any pa: t of it. CATAPHONICS, the fcience which conflders the pro¬ perties of refledled founds. CATAPHORxAj’ in medicine, the fame as coma. See Coma. CATAPHRACTA, in antiquity, a kind of coat of mail, which covered the foldier from head to foot. Hence, cataphradti were horfemen armed with the cataphradla, whofe horfes, as Salluft fays, were co¬ vered with linen full of iron plates difpoicd like fea¬ thers. CATAPLASM, an external topical medicine, prepared of ingredients of different virtues, according to the intention of the phyfician. Hence there are different forts of cataplafms with refpedt to the matter of which they confift, as emollient, refolvent, difcutient, fup- purative, corroborative, anodyne, and antifeptic cata¬ plafms. They are commonly applied hot, or luke¬ warm, rolled up in linen cloths, which by means of the oils which are added preferve heat for a conii- derable time; for which end alfo fome, upon thefe, apply a fwine’s or ox’s bladder, and fometimes on the top of all apply an earthen tile. CATAPULTA, in antiquity, a military engine contri¬ ved for the throwing of arrows, darts, and ftones, up¬ on the enemy. Some of thefe engines were of fuch force, that they would throw ftones of an hundred weight. Jofepbus takes notice of the furprifing effedfs of thefe engines, and fays, that the ftones thrown out of them beat down the battlements, knocked-off the angles of the towers, and would level a whole file of men, from one end to the other, were the phalanx never fo deep. CATARACT, in hydrography, a precipice in the chan¬ nel of a river, caufed by rocks, or other obftades, flopping the courfe of the ftream, from whence the water falls with a greater noife and impetuofity: Such are the cataradts of the Nile, the Danube, Rhine, and the famous one of Niagara in America. Cataract, in medicine and furgery, a diforder of the humours in the eye, by which the pupilla, that ought to appear tranfparent and black, looks opaque, grey, blue, brown, he. by which vifion is varioufly impe¬ ded, or totally deftroyed. See Medicine, and Sur¬ gery. CATARO, the'Capital of a territory of the fame name, in the Venetian Dalmatia, about twenty five miles fouth-eaft of Ragufa: E. long. 20', N. lat. 42° 25'. CATARACTES, in ornithology, the trivial name of a fpecies of larus. SeeLARus. CATARRH, in medicine, a diftillation or defluxion from the head upon the mouth and afpera arteria M . 1 and CAT (46 and through .them upon the lungs. See Medicine. CATASTASIS, in poetry, the third part of the an¬ cient drama, being that wherein the intrigue, or ac¬ tion, fet forth in the epitafis, is fupported and carried on, and heightened, till it be ripe for the unravelling in the cataftrophe. Scaliger defines it, the full growth of the fable, while things are at a Hand in that confu- fion to. which the poet has brought them. CATASTROPHE, in dramatic poetry, the fourth and lall part of the ancient drama, or that immediately fucceeding the cataftafis : Or, , according to others, the third only ; the whole drama being divided into protafis,, epitafis, and cataftrophe; or, in the terms of Ariftotle, prologue, epilogue, and exode. See Epic and Dramatic compofitions. CATCH-yfy, in botany. See Lychnis. Catch-pole, a term ufed by way of reproach, for the bailiff’s follower, or affdiant. CATCH-uwr/, among printers, that placed at the bot¬ tom of each page, being always the firft word of the following page. CATECHETIC. Catechetic fchools were buildings appointed foi the office of the catechift, adjoining to , the church, and called catechutnena: Such was that in winch Origen, and many other famous men, read catechetical ledures at Alexandria. See Catechu¬ men. CATECHISM, the name of a fmall book, defigned for inftrudting children in the principles of religion. The church of Rome, the church of England, the prelby- terian church, <&c. have all catechifms containing and enforcing their peculiar opinions. CATECHU, in the materia medica, the name of a troch confifting of Japan earth and gum arabic, each two ounces, and of fugar'of rofes fixteen ounces, beat together, with a.little water. It is recommended, as a mild reftringent, &C. C ATECHUMEN, a candidate, for baptifm, or one who prepares himfelf for. the receiving thereof. The catechumens, in church-hiftory, were the lowed order of Chrillians in the primitive church. They had. feme title to the common name of Chriftian, being a degree above pagans and heretics, though not confum- mated by baptifra. They were admitted to the date of catechumensi by the impofition of hands, and the lign of the crofs. The children, of believing.parents were admitted catechumens; as foon as ever they were capable of indrudlion : But at what age thofe of hea¬ then parents might be admitted, is not fo clear. As to the time of their continuance in this date, there were no general rules: fixed about it ; but the practice varied according to the difference of times and places, and the readinefs and proficiency of the catechumens tbemfelves. There were fon-r orders or degrees of catechumens-; the fird were thofe indrudted privately without the church,, and kept, at a didance, for, fome time, from the privilege, of entering the church, to make them the more eager and defirous ofits The next degree were the audiertcs, fo called from their being, admitted to hear fermons,and. the fcriptures read in the church,. ) CAT but were not allowed to partake of the prayers. The third fort of catechumens were the genu fltftenles, fo called, becaufe they received impofition of hands kneeling. The fourth order was the cojnpetentn & ' eletti, denoting the immediate candidates for baptifm, dr fuch as were appointed to be baptized the next ap¬ proaching fedival, before which, drift examination was made into their proficiency under the feveral dages of catechetical exercifes. After examination, they were exercifed.for twenty days together, and were obliged to fading and confef- fion: Some days before baptifm they went veiled ; and it.was cudomary to touch their ears, faying, Epha- tha, i. e. be opened^ as alfo, to anoint their eyes with clay; both ceremonies being in imitation of our Saviour’s praftice, and intended to (hadow out to the catechumens their condition both before and after their adroiflion into the Chridian church. CATEGORY, in logic, a feries or order of all the predicates or attributes contained under any genus. The fchool-philofophers didribute all the objefts of our thoughts and ideas into certain genera or claffes, not fo much, fay they, to learn what they do not know', as to communicate a didinft notion of what they do know ; and thefe claffes the Greeks called categories, and the Latins predicaments. Aridotle made ten categories, viz. quantity, qua¬ lity, relation, aftion, paflion, time, place, fituation, and habit, which are ufually expreffed by the follow¬ ing technical didich : Arbory fex, fervos, ardore, rifrigerat, ujios, Ruri eras ftabo, nec tunicatus ero. CATENARIA, in the higher geometry, the name of a curve line formed by a rope hanging freely from two points of fufpenfion, whether the points be horizontal or not. See Fluxions. CATERGI,.the name of the public carriers in the grand. Signior’s dominions. In Europe, the merchant or tra¬ veller gives- earned to the carrier ; but the catergi in Turky give earned to the merchant and others, as a fecurity that they will: certainly carry their goods, or not fet out with them. CATERPILLAR, in zoology, the name of all winged infefts when in their reptile or worm-date. See Na¬ tural History, Of infetta CATESBHCA, in botany, a genus of the tetrandria mo- nogynia clafs. The corolla is long. monopetalous, and fhaped like a tunnel ; the damina are within the faux; and the berry contains but one feed. There is but one fpecies, viz. the fpinofa, a native of Providence. CATH/ERETICS, in pharmacy, medicines of acaudiu nature, ferving to eat oflf proud flefli. CATHARTICS, in medicine, remedies which promote evacuation by dool. CATHEDRAL, a church wherein is a biihop’s fee or- feat. CATHETER, in furgery, a fidulous indrument, ufuaU ly made of filvef, to.be introduced into, the bladder, in order to fearch for the done, or difeharge the mine when fuppreffed. See Surgery. CATHETUS, in geometry, aline or radius falling per¬ pendicularly CAT t ‘ pendicularly on another line or furface: thus the ca- theti of a right-angled triangle are the two fides that include the right angle. Cathetus of incidence, in catoptrics, a right line drawn f|-om a point of the objed, perpendicular to the refteding line. Cathetus of reflexion, or of the eye, a right line drawn from the eye, perpendicular to the refieding line. Cathetus of obliquation, a right line drawn perpen¬ dicular to the fpeculum, in the point of incidence or refledion. Cathetus, in architedure, a perpendicular line, fup- pofed to pafs through the middle of a cylindrical bo¬ dy, as a balufter, column, of reflex vifion, and explains the laws and properties of reflec¬ tion. See Optics. CATULUS, in ichthyology. See Squauu s. CATUS-PARDUS, in zoology. See Felis. Catus'zibethicus. See Castor. CATZENELLIBOQEN, a city of Heffe, fituated up¬ on the Upper Rhine, in Germany, about fixteen miles north of Mentz.: E. long. 70 40', N. lat. 50° 20 . Ii is the capital of a.county of the fame.name.. L7 ) C A V CAVALIER., in fortification, an elevation of earth of different fhapes, fituated ordinarily in the gorge of a baftion, bordered with a parapet, and cut into more or lefs embrafures, according to the capacity of the ca¬ valier. Cavaliers are a double defence for the faces of the oppofite baftion : they defend the ditch, break the be- fiegers galleries, command the traverfes in dry moats, fcowr the failliant angle of the counterfcarpe where the befiegers have thbir counter-batteries, and infilade tho enemies trenches, or oblige them to multiply their pa¬ rallels : they are likewife very ferviceable in defending the breach, and the retrenchments of the befieged, and can very much incommode the entrenchments which the enemy make, being lodged in the baftion. CAVALtER, in the menage, one that underftands horfes, and is pradlifed in the art of riding them. CAVALRY, a body of foldiers that charge on horfe- back. They are divided into fquadrons, and encamp on thawings of the army. CAVAN, the capital of a county of the feme name, in the province of Ulfter, in Ireland, fituated about fixty miles north-weft of Dublin : W. long. 7? 35', and N. lat.. 540. CAUCALIS, in botany, a genus of the pentandria di- gynia clafs. The corolla is radiated; the fruit is hairy, and the involucra are entire. There are fix fpecies, three of which are natives of Britain, viz. the arvenfis, or fmall corq-parfley ; the anthrifeus, or hedge-parlley; and the leptophylla, or fine-leaved baftard parlley. CAUCASUS, a vaft ridge of mountains, running from the Leffer Afia through the north of Perfia to the Eaft- Indies ; thefe acquire different names in the feveral countries through which they pafs. CAUDIVERBERA, in zoology, the trivial name of a fpecies of lacerta. See Lacerta. CAVEAR, Cavker, orCAviARY, the fpawn, or hard roes of fturgeon, made into fmall cakes, an inch thick, and of an hand’s breadth, faked, and dried ia the fun. This fort of food is in great repute through¬ out Mufcovy, becaufe of their three lents, which they keep with a fuperftitious exaftnefs ; wherefore the I- talians fettled at Mnfcow, drive a very great trade in this commodity throughout that empire, becaufe there is a prodigious quantity of fturgeon taken at the mouth of the Wolga and of the other rivers which fall into the Cafpian fea. There is a pretty large quantity of this commodity confumed in Italy, and they are very well acquainted with it in France and England, where it is reckoned no defpjcable dilh. Tiie French and Italians getthe cavear from Arch¬ angel, but they feldom get it at the firft hand, fur they commonly buy it of the Englife and Dutch. CAVEAT, in law, a kind of procels in the fpiritual courts, to liop the proving of a will, the granting let¬ ters of adminiftration, to the prejudice of ano¬ ther. It is alfo ufed to ftop the inftitution of a clerk; to a benefice. CAVEATING, in fencing, is the lifting the fword from one fide of .that of your adverfary to the other. CAVEDG,. C A .u ( 4 CAVEDO, in commerce, a Ponuguefe- long meafure, equal to ccT.y-A.. Englifh inches. "CAVETTO, in architeilnre, a hollow member, or round concave moulding, containing a quadrant of a circle, and having a quite contrary effect to that of a quarter round : it is ufed as an ornament in cornices. CAVEZON, in the menage, a fort of nofe-band, either of iron, leather, or wood, fometimes flat, and at other times hollow or twifted, clapt upon the nofe of a horfe, to wring it, and fo forward the fuppling and breaking of the horfe. CAVIA-cobaya, a fynonime of the mus porcellinus, or Guinea-pig. See Mus. CAVILLON, a town of Provence in France, fltuated on the river Durance, about fifteen miles fouth of Avignon : E. long. 50, and N. lat. 430 50'. It is a bifliop’s fee, and fubjeft to the pope. CAUKING, or Caulking of .a Jhip, is driving oakum, or the like, into all the feams of the planks of a (hip, to prevent leaking, and keep out the water. Caulking-irons, are iron chiflels for that purpofe. Some of thefe irons are broad, fome round, and 0- therscgrpoyed. After the feams are flopped with oakum, it is done over with a mixture of tallow, pitch, and tar, as low as the fliip draws water. CAUL, in anatomy. See p. 266. col. 2. CAULIFLOWERS, in gardening, a much eftaemed fpecies of cabbage* Cauliflowers have of late years been fo much im¬ proved in Britain, as to exceed in goodnefs and mag¬ nitude any produced in moft parts of Europe ; and, by the dkill of the gardener, are continued for feveral months together, but the moft common feafon for them is in May, June, and July. CAULIS, in botany. See p. 641. col. 2. and Plate LVII. fig. 148. CAUSALTY, among metaphyficians, the adtion or power of acaufe in producing its effedt. Causalty, among miners, denotes the lighter, ful- phureous, earthy parts of ores, carried off in the ope¬ ration of waftiing. This, in the mines, they throw in heaps upon banks, which, in fix or feven years, they find it worth their while to work over again. CAUSE, that from whence any thing proceeds, or by virtue of which any thing is done : it flands oppofed to effedt. We get the ideas of caufe and effedt from our obfervation of the vicillitude of things, while we per¬ ceive fome qualities or fubftances begin to exift, and that they receive their exiflence from the due applica¬ tion and operation of other beings. That which pro-' duces, is the caufe; and that which is produced, the effedt: thus, fluidity in wax is the effedt of a certain degree of heat, which we obferve to be conftahtly pro¬ duced by the application of fuch heat. Firji Cause, that which adts of itfeif, and of its own proper power or virtue : God is the only firft caufe in this fenfe. Second Causes are thofe which derive the power and faculty of adtion from 4 firft caufe. Efficient Cxvses are the agents employed in the pro- dudtion-of any thing. 1 ) C A U Material Causes, the fubjedts whereon the agents work ; or the materials whereof the thing is produced. Final Causes are the motives inducing an agent to adt; or the defign and purpofe for which the thing was done. Pkj/ical Cause, that which produces a fenfible corpo¬ real effedt; as the fun is the phyfical caufe of light. ! Moral Cavse, that which produces a real effedt, but . in things immaterial; as repentance is the caule of forgivenefs. A mofal caufe is alfo defined, that which determines us, though not neceffarily, to do, or not to do, any thing; as advice, intreaties, commands, me¬ naces, <&c. It is to be obferved, that, in this fenfe, a moral caufe is only applicable to a free intelligent agent: it is alfo obfervable, that the latter notion of a phyfical as well as a moral caufe is the moft juft, clear, and diftindh Cause, among civilians, the fame with adtion. See Action. CAUSTICS, in phyfic, an appellation given to medi¬ cines of fo hot and fiery a nature, that, being applied; confume, and, as it were, burn the texture of the parts, like hot iron. Cauftics are generally divided into four forts, the common ftronger cauftic, the common milder cauftic, the antimonial cauftic, and the lunar cauftic. The ftronger cauftic is prepared by boiling to a fourth part any quantity of the lees of almond-foap, adding lime that has been kept in a veffel pretty clofe ftopt for feveral months ; the lime is to be added till all the liquor is abforbed, and the whole reduced to a pafte, which is to be kept in a veffel well ftopt. The common milder cauftic is prepared by taking e- qual parts of foft foap and frefh quick-lime, and mix¬ ing them at the time of ufing. The antimonial cauftic is prepared thus : Take of antimony one pound, of corrofive fublimate two pounds; and being reduced feparately into powder, mix them well, and diftill them in a retort with a wide neck, in a gentle heat of fand ; let what afeends into the neck of the retort be expofed to the air, that it may run in¬ to a liquor. The method of preparing the lunar cauftic is as fol¬ lows : Diffolve pure filver by a fand-heat, in about twice its weight of aqua-fortis ; then dry away the hu¬ midity with a gentle fire, afterwards melt it in a cru¬ cible, that it may be poured into proper moulds, care¬ fully avoiding over-much heat, left the matter fhould grow too thick. Caustic curve, in the higher geometry, a curve form¬ ed by tbe .concourfe or coincidence of the rays of light reflefted from fome other curve. Caustic glasses. See Burning-glasses. CAUSTICUM antimoniale, in the London Difpen- fatory, the fame with the oil of antimony. CAUSUS, or Burning-fever, a fpecies of continual fever, accompanied with a remarkable inflammation of the blood. CAUTERIZATION, the application of .cauteries to any pan of the body, CAUTERY, C E D ( , CAUTERY, in furgery, a medicine for burning, eating, or corroding any folid part of the body. Cauteries are diftinguiflied into two clafles, a&ual and potential: by a&ual cauteries, are meant red hot in- ftruments, ufuallyofiron, and by potential cauteries are underftood certain kinds of corroding, medicines. See Medicine, and Surgery. CAUTION, in the civil and Scots law, denotes much the fame with what, in the'daw of England, is called bail. See Bail. CAUTIONER, in Scots law, that perfon who becomes bound for another to the performance of any deed or obligation. As to the diifferent kinds and effedts of cautionry, fee Scots Law, title, Obligations arijing from confent. CAXA, a little coin made of lead, mixed with fdme fcoria of copper, (truck in China, but current chiefly at Bantam in the ifland of Java, and fome of the neigh¬ bouring iflands. The caxas are of two kinds, great and fmall. Of the fmall, 300,000 are equal to fifty-fix livres five fols French money; and of the great, 6000 are equal to four (hillings and fixpence fterling. CAXAM ALCA, the name of a town and diftridt of Pe¬ ru, in South America, where there was a mod fump- tuous palace belorfging to the Yncas, and a magnificent temple dedicated to the fun. It was at Caxamalca that Pizarro put to death Athualpha, their lad king. CAY, in zoology, a fynonime of the fimia midas. See Simi A. CAZEROM, or Cazeron, a city of Perfia, the capi- - tal of the province of Kurch Schabour, fituated in 70° E. long, and 290 1 s' N. fat. CAZIMIR, a town of Poland, in the palatinate of Lublin. CEANOTHUS, in botany, a genus of the pentandria monogynia clafs. The petals are vaulted ; and the berry is dry, having three cells, containing each one feed. There are three fpecies, none of them natives of Britain. CECROPIA, in botany, a genus of the dicecia diandria clafs. The fpatha of the male is caducous; the a- menta are imbricated with helmet-fhaped fcales ; and the corolla is wanting. The germina of the female are imbricated ; it has but one (tylus ; the digma is lacerated; and the berry contains but one feed. There is one fpecies, viz. the peltata, a native of Ja¬ maica. CEDAR, in botany, the Englifli name of a fpecies of juniperus. See Juniperus. CEDRELA, in botany, a genus of the pentandria mo¬ nogynia clafs. The calix is bell-fhaped, and di¬ vided into three fegments ; the corolla is fliaped like a funnel, and has five petals inferred into the bafe of the receptacle ; the capfule is lignous, and has five cells and five valves ; the feeds are imbricated on the back part, and have membranaceous edges. There is but one fpecies, viz. the odorata, a native of Ame¬ rica. CEDRUS, in botany. See Juniperus, and Pinus. CELANDINE, in botany. See ChemIjonium. Vol. II. No. 32. 3 9 ) CEL CELASTRUS, in botany, a genus of the pentandria monogynia clafs. The corolla confids of five open pe¬ tals ; the capTule is triangular, and has three cells ; and the feeds have a calyptra. There are five fpecies, none of them native# of Britain. CELERES, in Roman antiquity, a regiment of body¬ guards, belonging to the Roman kings, edablifhed by Romulus, and compofed of 300 young men, chofen out of the mod illudrious Roman families, and. ap¬ proved by the fuffrages of the curiae of the people, each of which furniflied ten. CELERI, in botany, the Englifli name of the apium graveolens, or celery, which is cultivated in our gar¬ dens as a pot-herb. CELERITY, in mechanics,-the fwiftnefs of any body in motion. It is alfo defined to be an afle&ion of motion, by which any moveable body runs through a given fpace in a given time. See Mechanics. CELESTINS, in church-hidory, a religious order of Chridians, reformed from the Bernardins by pope Ce- ledin V. Their rules are divided into three parts ; the fird, of the provincial chapters, and the elexdions of fuperiors ; the fecond contains the regular obfer- vances ; and the third, the vifitation and correftion of the monks. The Celedins rife two hours after midnight to fay) matins : they eat no fleih at any time, except when they are fick : they fad every Wednefday and Friday to the fead of the exaltation of the holy crofs ; and from that fead to Eader, every day. CELIBACY, the date of unmarried perfons, to which, according to the dodtrine, or at lead the difcipline, of the church of Rome, the clergy are obliged. That celibacy has no pretence of divine or apodoli- cal inditution, feems no difficult point to prove : whence it is, at fird, hard to conceive from what mo r tive the court of Rome perfided fo very obdinately to impofe this inditution on the clergy. But we are to obferve, that this was a leading dep to the execution 6f the projedt formed of making the clergy indepen¬ dent of princes, and rendering them a feparate bodv, to be governed by their own laws. In effedt, while prieds had -children, it was very difficult to prevent their dependence upon princes, whofe favours have fuch an influence on private men ; but having no fa¬ mily, they were more at liberty to adhere to the pope. CELOSIA, in botany, a genus of the pentandria mo¬ nogynia clafs. The calix has three leaves ; the fla- mina are joined to the bafe of a plaited nedlarium ; and the capfule opens horizontally. There are eight fpecies, none of them natives of Britain. CELSIA, in botany, a genus of the didynamia angio- fpermia clafs. The calix is divided into five fegments - the corolla is rotated ; the filaments are barbed ; and the capfule is bilocular. There is but one fpecies, viz. the orientalis, a native of Greece. CELTIS, in botany, a genus of the polygamia monoe- cia clafs. The calix of the hermaphrodite is divided into five fegments ; it has no corolla; there are five N dami*a. C E N (50 {lamina, and two flyli ; the drupa contains but one fe6d. The calix of the male is divided into fix feg- ments ; it has no corolla ; and the {lamina are fix. The fpecies are three, none of them natives of Bri¬ tain. ' ' < CEMENT, or Clement. See Clement. . CEMENTATION. See Cementation. CEMETERY. See Coemetery. CENADA, a town of the Venetian territories in Italy, fituated about thirty-two miles north of Padua : E. long. 120 40', and N. lat. 46° $ . GENCHRAMIDEA, in botany. See Clusia. CENCHRIS, in zoology, a fynonime of the boa con- ftrisSor. See Boa. CENCHRUS,' in botany, a genus of the polygamia mo- ncecia clafs. The involucrum is laciniated, and in- clofes two flowers ; the calix is a two flowered gluma, one of the flowers being a male, and the other a fe- ( male. The corolla of the hermaphrodite is a blunt gluma ; the {lamina are three ; and the ftylus is bifid ; there is but one feed. The corolla of the male is like- wife an obtufe gluma ; and there are three,{lamina. The fpecies arc fix, none of them natives of Britain. GENCONTLTAOLLI, in ornithology. See Tor- < DUS. CENOBITE, or Coenobite. See Coenobite. CENOTAPH, in antiquity, a monument erefted in ho¬ nour of the dead, but not containing any of their re¬ mains. Of thefe there were two forts ; one eredled for fuch perfons as had been honoured with funeral rites in another place ; and the fecond fort, for thofe that had never obtained a juft funeral. The fign whereby honorary fepulchres were diftin- guifhed from others, was commonly the wreck ,of a (hip, to denote the deceafe of the perfon i.n fome fo¬ reign country. CENSER,, a facred ijrftrument made ufe of in the reli¬ gious rites of the ancients. It was a vafe, containing incenfe to be ufed in facrificing to the gods. Cenfers were likewife in ufe among the Jews, as we find in I Kings vii. 50. The cenler is alfo ufed in Romifti churches. CENSOR, in Roman antiquity, a magiftrate, whofe bufipefs it was to reform the manners, and to value the eftates of the people. There were two cenfors firfl created in the 31 i-th year of Rome, upon the fenate’s obferving thar the 1 confuls were generally fo much taken up in military a£tions as -to have no leifure to attend to private af¬ fairs. At fir 11 they were chofen out of the fen ate, but after the plebeians had got the ionfulate open to them, they foon arrived at the cenforlhip. After the cenfors were ele&ed in the comitia cen- 1 turialia, they proceeded to the capitol, where they took an oath not to manage either by favour or difaffedlion, but to adl equitably and impartially through the whole courfe of their adminiltration : and, notwithftandmg their great authority, they were obliged to give an ac¬ count of their management to the tribunes and tsdUes* curules. In proccfs of time, the dignity of this office dwindled very much j under the emperors it funk to > ) CEN nothing, as their majellies engrofled all the branches- of that jurifdi&ion. The republic of Venice has at this day a cenfor of manners of their people, whofe office lalis fix months. Censors of hoiks, are a body of do£tors or others ella- bliffied in divers countries, to examine all books before they go to the prefs, and to fee they contain nothing contrary to faith and good manners At Paris, the faculty of theology claim this privi- legej as granted to them by .the pope; but in 1624, new commiflions of four doblors were created, by let- ters-patent, the foie cenfors of all books, and anfwer able for every thing contained therein. In England, we had formerly an officer of this kind, under the title of Licenfer of the prefs ; but, fince the revolution, oUr prefs has been laid under no fuch re- firaint. CENSURE, a judgment which condemns fome book, perfon, or adlion, or more particularly a- reprimand from a fuperior. Ecclefiaftical cenfures, are penalties by Which, for fome remarkable mifbehaviour, Chri- ftians are deprived of the communion of the church, or prohibited to execute the facerdotal office. CENSUS, in Roman antiquity, an authentic declaration made before the cenfors, by the feveral fubjeHs of the empire, of their refpedive names and places of abode.. This declaration was regiflered by the cenfors, and contained an enumeration, in writing, of all the eflates, lands, and inheritances they pofleffed ; their quantity, quality, place, wives, children, domeilics, tenants, {laves. . The cenfus was inllituted by Servius Tullius, and was held every five years. It was of great fervice to the republic, became, by means of it, they difeovered the number ef citizens capable of bearing arms, and the money they could afford for thejexpence of a war. It went through all ranks of people, though under dif¬ ferent names : that of the common people was called eenfus ; that of the knights, cenfus. recenfio, recog- nilio ; that of the fenators, lettio, reteflio. The cenfus which intitled one to the dignity of a- knight, was 400,000 feflerces : that of a fenator, was double that fum. In the Voconian law, cenfus is ufed fora man, whofe eflate- in the Cenfor’s books is valued at 100,000 fefterces. CENTAUR, in ancient poetry, denotes a fabulous kind of animal, half man, half horfe. The Theffalians who firrt taught the art of break¬ ing horfes, appearing on horfeback to make only one body with the animaTon which they rode, gave rife to-' the fidlion of the hippocentaur. CENTAUREA, in botany, a genus of the fyngenefia polygamia fruftranea clafs. The receptacle is brfilly; the pappus is fimple ; the rays of the corolla are tun-- nel-ffiaped, long, and irregular. There are 61'fpe¬ cies, five of which are natives of Britain, v*z. the cyanus, or blue-bottle ; the fcabiofa, or . great knap¬ weed ; the jdcea, or common knapweed; the calci- trapa, or flar-thiftle; and the fdlftitialis,' or St Bar- • naby ’s thiilie,. CENTAURY. C E N ( I CENTAURY. See Chelidoni'um. Center of gravity, in mechanics, that point about which all the pafts of a body do, in any fituation, ex¬ actly balance each other. See Mechanics. Center of motion, that point which remains at reft, while all the other parts of a body move about it. See Mechan cs. CENTESIMATION, a milder kind of military punifli- ment, in cafes of defertion, mutiny, and the like,, when only every hundredth man is executed. CENTIPES, in zoology. See Scolopendra. CENTON iRII, in antiquity, certain officers of the Roman army, who provid d tents and other fluff-, called centones, made ufe of to quench the fire, which the enemy’s engines threw into the camp. Thefe centonarii kept with the carpenters and other officers of the artillery. CENTRAL forces, the powers which eaufe amoving body to tend towards, or recede from the centre of motion. See Mechanics. . Central rule, a rule difcovered by Mr Thomas Baker, whereby to find the centre of a circle defigned to cut the parabola in as many points, as an equation to be conftrudled hath real roots. Its principal ufe is in the coaftrudtion of equations, and he has applied it with goodfuccefs as far as biquadratics. The central rule is' chiefly founded on this property of the parabola, that if a line be infcribed in that durve perpendicular to any diameter, a redtangle formed of thefegments of the ipfcript, is equal to the redangle of the intercepted diameter and parameter, of the axis. The centraf rule has the advantage over Cartes and De Latere’s methods of conftruding equations, in that both thefe are fubjed to the trouble of preparing the- equati n, by: taking away the fecond term. CENTRIFUGAL force, that force by which‘all bo¬ dies that move round any other body in a curve, en-. deavour to fly off from the axis of their motion in a tangent to the periphery of the curve, and that in every point of it. See Mechanics. CENTRINA. in ichthyology, the trivial name of a fpecies of fqualus. See Squalus. CENVRIPETAL force,, that force by which a body- is every where impelled, or any how tends towards- fome point as a centre. See Mechanics. GENTRISCUS, in ichthyology, a genus belonging to the.order of amphibia names. The. head .gradually ends in a narrow fnout; the aperture is broad and flat; the belly is carinated; and the belly-fins are united. There are two fpeciesv viz, i. The fcutatus has its back covered with a fmooth bony ffiell, which ends fin a fharp fpine, under which is the tail ; but the back- fins are between the tail and the fpine. It is a native of the Eaft Indies. 2. The fcol- pax has a rough fctbrous body, and a ftrait extended tail. It has two belly-fins, with four rays in each, and has no teeth. It is found in the Mediterranean. GENTUMVIRI, in Roman antiquity, judges appointed, to decide common caufes among the people : they were. ; 1 ) CEP chofen three out of each tribe ; and though five more than an hundred, were neverthelefs called centumviri, from the round number centum, an hundred. CENTUNCULUS, in botany, a genus of the tetran- dria monogynia clafs. The calix confifts of four feg- ments ; the corolla has four divifions, and open ; the ftamina are Ihort; and the capfule has but one cell. There is only one fpecies, viz. the minimus, or baftard pimpernel, a native of Britain. CENTURION, among the Romans, an officer in the infan. ry, who commanded a century, or an hundred men. The centurions held the firft rank in the firft cohort of a legion, and two of them the place of the two fir ft haftati or pike-men : the firft among the principes was alfo a centurion. The centurion, primipilus was the chief of the cen¬ turions : he was not under the command of any tri¬ bune, as all the reft were ; he'had four centuries un¬ der his.direction, and guarded the ftandard and the ea¬ gle of the legion. CENTURY, in a general fenfe, any thing divided into < or confiding of an hundred parts. The Roman people, when they were aflembled for: the eledting of magiftrates, enadiing of laws, or deli¬ berating upon any public affair, were always diyideii into centuries^ and voted by centuries,, in order that their fuffrages might be the more eafily collefled ; whence thefe aflemblies were called comitia cenluriata* The Roman cohorts were alfo divided into centuries. See Centurion and Cohort. Century, in chronology, the fpace of one hundred • years-. 1 his method of computing by centuries is generally obferved in church hiftory, commencing from the time 0/our Saviour’s incarnation; in which fenfe we fay.' the'firft century, the fecond century, lire. C.e n t u r i ex /of Magdeburg, a famous ecclefiafticafhi-.- llory, ranged into thirteen centuries, carried down to the year 1298, compiled by feveral hundred Prote-1 ft-ants -of Magdeburg, the chief of whom was Matthias Flacius Ulyricus. CENTUSSIS. in Roman antiquity, a coin containing ; an hundred affes.- CEPA,.in botany, the trivial Hame.of a fpecies of alii.-! um. See Allium.. CEPAEA, in botany.. See Sedum. CEPHALANTHUS, in botany, a genuS.of the tetran- dria mdnogynia ciafs. It.has po common calix;. the proper calix is tunnel-ftaped ; the receptacle is globular, and naked; andffhe feeds are downy. There is but orte fpecies, viz. the oecidentalis, .a. native of America. CEPHALIC, in a general meaning, fignifies. any thing belonging to the head. Ce phal'i CKtntdicints are. remedies for.diforders of the head./ Cephalic in anatomy. See p. 241. CEPHALONIA, the capital of an ifland of the fame name, fituaced in the Mediterranean, near, the coafib - o£. G E II (52 of Epirus, and fubjuft to the Venetians: E. long. 21 and N. lat. 38° 30'. CEPiIALOPHARYNGjEI, in anatomy. Seep. 302. CEPhLiLUS, in ichthyology, the trivial name of a fpe- cies of mugil. See Mugil. CEPHEUS, in aftronomy, a conftellation of the nor¬ thern hentifphere^ CEPHUS, in ornithology, a fynonime of a fpecies of larus. See Larus. CERAM, an ifland in the Indian ocean, between the Molucca iflands on the north, and thofe of Amboyna and Banda on the fouth, lying between 126° and 1290 E. long, and in 30 S. lat. It is about one hundred and fifty miles long, and fixty broad ; and here the Dutch have a fortrefs, which keeps the natives in fubje<5tion. CERAMBYX, in zoology, a genus of infedts of the beetle kind, belonging to the order of infedla coleop- tera. The antennse are long and fmall; the breaft is Ipinous or gibbous; and the elytra are linear. There are no lefs than 83 fpecies enumerated by Linnseus, principally diftinguiihed by the figure of the bread. CERASTES, in zoology, the trivial name of a fpecies of coluber; it is likewife the trivial name of a fpe¬ cies of anguis. SeeANGuis, and Coluber. CERASTIUM, in botany, a genus of the decandria pentagynia clafs. The calix has five- leaves ; the pe¬ tals are bifid; and the capfule is unilocular, and opens a: the top. There are fixteen fpecies, feven of which are natives of Britain, viz. the vulgatum, or narrow- leaved moufe-ear chickweed ; the vifcofum, or broad¬ leaved moufe-ear chickweed ; the femidecandrium, or lead moufe-ear chickweed; the arvenfe, or corn moufe-ear chickweed; the alpinum, or mountain moufe-ear chickweed; the tomentofum, or wooly moule-ear chickweed; and the aquaticum, or mardi moufe-ear chickweed. CERASUS, in botany, the trivial name of a fpecies of prunus. See Prunus. CER ATE, in pharmacy, a kind of ointment applied to ulcerations, excoriations, &c. There are four kinds of cerate, viz. the white cerate> which is compofed of a quarter of a pint of olive-oil, four ounces of tyhite wax, and half an ounce of fpermaceti, liquified -together and iharred till ,the cerate be cold. The yellow cerate is compofed of half a pound of yellow bafilicum ointment,- and an ounce of yellow wax, melt¬ ed together. The ceratum epuhticum, is compofed of one pint of olive-oil, and of yellow wax and cala¬ mine prepared each half a pound. Liquify the wax with the oil, and, as fooh as the mixture begins to grow diff, fprinkle in the calamine, keeping them condantly dirring till the cerate is quite cold. The mercurial cerate is compofed of yellow wax, hogs lard dried, each half a pound .; three ounces of quick- lilver; and one dram of fimple balfam of fulphur. Melt the wax with the lard, then gradually add this mixture to the quick-filver and balfam of fulphur pre- vioufly ground together. CERATION, the name given by the ancients to the ) CEE fmall feeds of the ceratonia, ufed by the Arabian phyficians, as a weight to adjud the dofes of medi¬ cines ; as the grain weight with us took its rife from a grain of barley. Ceration, or Ceratium, was alfo a filver.coin, e- qual to one third of an obolus. CERATOCARPUS, in botany, a genus of the monoe- cia monandria clafs. The calix of the male is divi¬ ded into two parts ; it has no corolla; and the filament is long : The calix of the female confids of two leaves connjded to the germen ; it has no corolla; the dy- li are two; and the feeds are bicorned and comp ref- fed. There is but one fpecies, viz. the arenarius, a native of Tartary. CERATOGEPHALOIDES, in botany. See Ver- BESINA. CERATOCEPHALUS, in botany. SeeBiDENs. Ceratoides, in botany. See Urt 1 ca. CERATONIA, in botany, a genus of the polygamia polycecia clafs. It is a native of Sicily, Crete, and other eadern countries. CERATOPHYLLUM, in botany, a genus of the mo- noecia polyandria clafs. The calix of the male is di¬ vided into many fegments ; it has no corolla; and the flamina are from 16 to 20. The calix and corolla of the female are the fame with thofe of the male; it has one pidil, no dylus, and one naked feed. There are two fpecies, one of which, viz. the demerfum or horned pondweed, is a native.of Britain. CERATUM, in pharmacy. See Cerate. CERBERA, in botany, a genus of the pentandria mo- nogynia clafs. The fruit is a drupa containing one feed. There are three fpecies, all of them natives of the Indies. > CERCELE, in heraldry. A crofs cercele is a crofs which opening at the ends, turns round both ways, like a ram’s horn. See Cross. CERCIS, in botany, a genus of the decandria mono- gynia clafs. The calix is five-teethed, and gibbous below; the corolla is papilionaceous, with a fhort vex- illum under the wings; the capfule is a legumen. There are two fpecies, none of them natives of Bri¬ tain. CEREBELLUM, in anatomy. See p. 286. CEREBRUM, in anatomy. See p. 285. CEREMONY, an afiemblage of feveral actions, forms, and circumdances, ferving to render a thing more magnificent and folemn; particularly ufed to denote the external rites of religious worlhip, the formalities of introducing ambafladors to audiences, «/Af a city of Burgundy in France, thirty-two miles fouth of Dijon : E. long. 50, N. lat. 46° 4c/. It is the fee of a bdhop. CHALYBEAT, in medicine, an appellation given to any liquid, as wine or water, impregnated with parti¬ cles of iron or fteel. Dr Monro, profeffor of anatomy.at Edinburgh, by pouring a tindure of galls into common water, ^nd diffolving therein-a fmall quantity of fal martis, add¬ ing fome filings of iron, and oil of yitrol, ’procured, a water exadly like the natural chalybeat water ; and he is of opinion, that where thefe are not to be had, the artificial water may be made to anf.ver all their inten¬ tions, according to its being more or lefs clofely kept, or expofed in the air or heat, CHAM, or Khan, a word of much-the fame import with king in Engliih : It is the title of the fovereign princes of Tartary, and is likewife applied to the principal noblemen in Perfia. Cham, in geography, a town of the Bavarian palatinate, fituated on a river of the fame name,, about twenty- five miles north-eafi of Ratifbon; E. long. 130, N. lat. 490 15'. CHAMA, in zoology, a genus of (hell-fifti belonging to the order of Vermes teftacea. The (hell is thick, and has two valves; it is an animal of the oyfier kind. Linnaeus enumerates 14 fpecies, principally difiinguiff- ed by the figure of their (hells. CHAMvEBATOS, in botany. SeeRuBus. CHAM/EBUXUS, in botany.. See Pol.ygala. CHAMgECERASUS, in botany. See LoNicERA. CHAMAlCLEMA, in botany. See Hedera. CHAMAlCRISTA, in botany. See Cassia. CHAMZEDAPHNE, in botany. ' SeeKALMiA. CHAMAiDRYS, in botany. See Veronica. CHAMAlLE \, in botany. See Cenorum. CHAMAlLEON, in zoology, the trivial name of a fpe¬ cies of lacerta See Lacerta. CHAM ALL INUM; in botany. See Linum. CHAMAlMILUM, in botany. See Matricaria. CHAMAiNERION. in botany. See Epilobium. CHAMALPITYS, fn botany. SccTeucrium. CHAMAlRHODODENDROS, in botany. See A- z'alea. CHAMASROPS, or Humble palm, in botany, ai ge¬ nus ranged under the palms flabellifolis of Linnaeus. It is a native of Spain. Privy j tA/f'r Aft: C H A (57 Prtvy-C h a mbe r , Gentlemen of the privy-chamber, are fervants of the king, who are to wait and attend on him and the queen at court, in their diveriions, &c. Their number is forty-eight under the lord- chambeilain, twelve of whom are in quarterly waiting, and two of thefe lie in the privy-chamber. In the abfence of the lord-chamberlain, ot vice¬ chamberlain, they execute the king’s orders : at coro¬ nations, two pf them perfonate the dukes of Aquitain and Normandy: and fix of them, appointed by the lord-chamberlain, attend ambalfadors from crowned heads to their audiences, and in public entries. The gentlemen of the privy-chamber were inllituted by Henry VII. Chamber, in policy, the place where certain aflemblies are held, alfo the aflemblies themfelves. Of thefe, fome are eftablilhed for the adminiftration of juflice, others for commercial affairs. Of the firft kind are, x. Star-chamber, fo called, becaufe the roof was painted with ftars ; the autho¬ rity, power, and jurifdi&ion of which are abfolutely abolifhed by the ftatute 17 Car. I. 2. Imperial cham¬ ber of Spire, the fupreme court of judicatory in the empire, ere&ed by Maximilian I. This chamber has a right of judging by appeal, and is the laft refort of all civil affairs of the flates and fubjedts of the empire, in the fame manner as the aulic council of Vienna; Neverthelefs it is reflrained in feveral cafes ; it takes no notice of matrimonial caufes, thefe being left to the pope ; nor of criminal caufes, which either belong to particular princes or towns in their refpe&ive terri¬ tories, or are cognizable by all the ftates of the em¬ pire in a diet. By the treaty of Ofnaburg, in 1648, fifty afleffors were appointed for this chamber, where¬ of twenty.four were to be Proteftants, and twenty-fix Catholics; befides five prefidents, two of them Pro¬ teftants, and the reft Catholics. 3. Chamber of ac¬ counts, a-^bvereign court in France, where accounts , are rendered of all the king’s revenues, inventories, and avowels thereof regiftered; oaths of fidelity ta¬ ken, and other things relating to the finances tranfac- ted. There are nine in France, that of Paris is the chief; it regifters proclamations, treaties of peace, naturalizations, titles of nobility, i&c. All the mem¬ bers wear long black gowns of velvet, of fattin, or da- mafk, according to their places. 4. Ecclefiaftical chambers in France, which judge by appeal of differ¬ ences about colledting thetythes. 5. Chamber of au¬ dience, or grand chamber, a jurifdidtion in each par¬ liament of France, the counfellors of which are called jugeurs, or judges, as thofe of the chamber of in- quefts are called rapporteurs, reporters of procefles by writing. 6. Chamber of the edidt, or miparty, a court eftablifhed by virtue of the edidt of pacification, in favour of thofe of the reformed religion. This chamber is now fupprefled. 7. Apoftolical chamber of Rome, that wherein affairs relating to the reve¬ nues of the church and the pope are tranfadted. This council confifts of the cardinal-camerlingo, the gover¬ nor of the rota, a treafurer, an auditor, a prefident, one advocate-general, a folicitor-general, a commifla- Vol. II. No. 32. 3 ) C II A ry, and twelve clerks. 8. Chamber of London, an apartment in Guildhall, where the city-money is de- pofited. Of the laft fort are, 1. The chambers of commerce. 2. The chambers of aflurance. And, 3. The royal or fyndical chamber of bookfellers in France. The chamber of commerce is an afl'embly of msr- chants and traders, where the affairs relating to trade are treated of. There are feveral eftablifned in moft of the chief cities of France ; and in our own coun¬ try, we have lately feen chambers of this kind eredled for carrying on the Britifh herring-fifhery. Chamber of aflurance in France, denotes a fociety of merchants and others for carrying on the bufinefs of infuring; but in Holland, it fignifies a court of juftice, where caufes relating to infurances are tried. Chamber of bookfellers in Paris, an aflembly confifting of a fyndic and afliftants, eledted by four delegates from the prin¬ ters, and twelve from the bookfellers, to viflt the books imported from abroad, and to fearch the houfes of fellers of marbled paper, printfellers, and dealers in printed paper for hangings, who are prohibited from keeping any letters proper for printing books. In the vifitation of books, which ought to be performed by three perfons at leaft from among the fyndic and ailiftants, all libels againft the honour of God and the welfare of the ftate, and all books printed cither with¬ in or without the kingdom in breach of their regula¬ tions and privileges, are ftopt, even with the merchan- difes that may happen to be in the bales with fuch li¬ bels, or other prohibited books. The days appointed for this chamber to meet, are Tuefdays and Fridays, at two o’clock in the afternoon. CHAMBERLAIN, an officer charged with the ma¬ nagement and dire&ion of a chamber. See Cham¬ ber, in policy. There are almoft as many kinds of chamberlains as chambers, the principal whereof are as follows. Lord Chamberlain of Great Britain, the fixth great officer of the crown ; to whom belongs livery and lodg¬ ing in the king’s court; and there are certain fees due to him from each archbilhop or bifliOp, when they perform their homage to the king ; and from all peers at their creation, or doing their homage. At the co ronation of every king, he is to have forty ells of crimfon velvet for his own robes. This officer, on the coronation-day, is to bring the king his fliirt, coif, and wearing cloaths; and after the king is dref fed, he claims his bed, and all the furniture of his chamber for his fees : he aifo carries at the coronation, the coif, gloves, and linen to be ufed by the king on that occafion ; alfo the fword and fcabbard, the gold to be offered by the king, and the robes-royal and crown: he drefl'es and undrefles the king on that day, waits on him before and after dinner, ,, in law, is the accidental killing of a man, not altogether without the killer’s fault, though without any evil intention ; and is where one is doing a lawful ae, a kind of portico, or gallery, ufually in or near a church-yard, over which were anciently laid the bones of the dead, after the flefh was wholly confumed. Charnel-houfes are now ufually adjoining to the church. CHARNUB, in botany. See Ceratonia. CHART, or Sea-chart, an hydrographical map, or a proje<5Hon of fome parts of the earth’s fuperficies in piano, for the ufe of navigators. See Naviga- tiom. CHA RT A - magna. See Magna chart a. CHARTER, in law, a written inftrument or evidence of things adted between one perfon and another. Charters of private perfons, are deeds and inftru- ments for the conveyance of lands, it Is called oil 'of vitriol ; on account of a certain unffuofity belonging to it. If the vitriolic acid cotitain much water, it is then called fpirit of vitriol. When it does not contain e- nough to render it fluid, and fo is ,in a folid form, it is named the icy oil of vitriol. When oil of vitriol, highly concentrated, Ss mixed with water, they rulh into union with fuch an impetuofi- ty, that, the moment they touch each other, there arifes a hiding noife, like that of red-hot iron pidngfed in cold water, together with a very confiderable degree of heat proportioned to the degree in which the' Acid was con¬ centrated. If inflead of mixing this concentrated acid with water, you only leave it expof d to the air for fome time, it attraffs the moillure thereof, and imbibes it moll gree¬ dily. Both its bulk and its weight are increafed by this accelflon ; and if it be under an icy form, that is, if it be concreted, the phlegm thus acquired will foon refolve it into fluid. S T II Y. The addition of water renders the vitriolic acid, and indeed all- other acids, weaker in one fenfe ; which is, that when they are very aqueous, they leave on the tongue a much fainter talte of p.cidity, and are lefs ac¬ tive in the folution of fome particular bodies: But that occafions no change in the ftrength of their affinities^ but in fome cafes rather enables them to diffolve feveral fub- ftances which, when well dephlegmated, they are not capable of attacking. The vitriolic acid combined to the point of faturation with a particular abforbent earth, well known, forms a neutral fait that cryllallizes. This fait is called alusn, and the figure of its cryllals is that of an offahedron or folid of eight fides. Thefe offahedra are triangular py¬ ramids, the angles of which are To cut off that four of the furfaces are hexagons, and the other four triangles. There are feveral forts of alum, which differ accord¬ ing to the earths combined with the vitriolic acid. Alum diffolves eafily in water, 'and in cryftallizatipn retains a confiderable quantity of it; which is the reafbn that bein'g expofed to the fire it readily melts, fwelling and puffing up as its foperfluous raoifture exhales. \Y"hen that is quite evaporated, the remainder is called burnt alum, and is very difficult to fufe. The acid of the alum is partly diilipated by this calcination. Its tafte is faltilh, with a degree of roughnefs and afttingency. The vitriolic acid combined with certain earths forms a kind of neutral fait c?A\z& felenites, which cryflallizes in different forms according to. the nature of its earth. There are numberlefs fprings of water iijfeffed with dif¬ folved felenitts; but when thjs fait is once cryftallized, it is exceeding difficult to diffolve. it-in water' a fecond time. For that purpofe a-very great quantity of water is neceffary, and moreover it mull boil; for, as it cools, moll of the diffolved felenites takes a folid form, and falls in a powder to the bottom of the veffel. If an alkali be prefented to the felenites, or to alum, thefe falts will be thereby decompofed; that is, the acid will quit the earths; and join the alkali, with which it hath a greater affinity. " And from this con- junffion of the vitriolic acid with a fixed alkali there re- fults another-fort of neutral fait, which is called arca¬ num duplicatum, fal de duobus, and vitriolaied tartar, becaufe one of the fixed alcalis moll in ufe is called fait of taitar. Vitriolatfed tartar is almoll as hard to diffolve in wa¬ ter As the felenites. It Ihoots into eight-fided cryllals, having the apices of the pyramids pretty obtufe. Its tafte is fahifh, inclining to bitter ; and it decrepitates on burning coals. It requires a very great. degree of fire to make it flow. The vitriolic acid is capable of uniting with the phlo- giftort, or rather it has a greater affinity with it than with any other body: whence it follows, that all compounds of which it makes a part may be decompofed by means of the phlogillon. From the conjunffion of the vitriolic acid with the phlogillon arifes a compound called mineral fulphur, be¬ caufe it is found perfectly formed in the bowels of the earth. It is aifo called fu'lphur vivum, or fimply ful- phur. : . Sulphur CUE M ] Sulphur is abfolutely infoluble in water, and incapable of contrafting any fort of union with it. It melts with a very moderate degree of heat, and fublimes in fine light downy tufts called flowers of fulflhur. By being thus fublimed it fuffers no decompofition, let the opera¬ tion be repeated ever fo often; fo that fublimed fulphur, or flower of fulphur, hath exactly the fame properties as fulphur that has never been fublimed. If fulphur be expofed to a brilk heat in the open a*r> in takes fire, burns, and is wholly confumed. This de- flagration^of fulphur is the only means we- have of de- compofing it, in order to obtain its acid in purity. The phlogifton is deltroyed by the flame, and the acid ex¬ hales in vapours ; thefe vapours colledted have all the properties of the vitriolic acid, and differ from it only as they flill retain fome portion of the phlogifton ; which, however, fot^n quits them of its own accord, if the free accefs of the common air be not precluded. The portion of phlogifton retained by the acid of fulphur is much more confiderable when that mineral is burnt gradually and flowly : in that cafe the vapours •which rife from it have fuch a penetrating odour, that they inftantaneoufly fuffocate any perfon who draws in a certain quantity of them with his breath. Thefe va¬ pours conftitute what is called the volatile' fpirit of fitphur. There is reafon to think this portion of phlo¬ gifton which the acid retains is combined therewith in a manner different from that in which thefe two are united in the fulphur itfelf; for nothing but adtual burning is capable of feparatinj* the vitriolic acid and the phlogi¬ fton, which by their union form fulphur; whereas in the volatile fpirit of fulphur they feparate fpontaneoufly when expofed to the open air; that is, the phlogifton flies off and leaves the acid, which then becomes in e- very refpedt fimilar to the vitriolic acid. That the volatile fpirit of fulphur is a compound, ap¬ pears evidently from hence, that whenever the vitriolic acid touches any fubftance containing the phlogifton, •provided that phlbgifton be difengaged or opened to a certain degree, a volatile fpirit of fulphur is infallibly and immediately generated. This fpirit hath all the properties of acids, but confiderably weakened, and of courfe lefs perceptible. It unites with abforbent earths or fixed alkalis; and with them forms neutral falls: but when combined therewith it may be feparated from them by the vitriolic acid, and indeed by any of the mineral acids, becaufe its'affinities are weaker. Sul¬ phur hath the property of uniting with abforbent earths, but not near fo intimately as with fixed alkalis. If equal parts of fulphur and an alkali be melted toge¬ ther, they incorporate with each other; and from their conjundion proceeds a compound of a moft unpleafant fmell, much like that of rotten eggs, and of a red co¬ lour nearly refembling that of an animal liver, which has occafioned it to bear the name of hepar fulphuris, or liver of fulphur. In this compofxtion the fixed alkali communicates to the fulphur the property of diffolving in water: and hence it comes that liver of fulphur may be made as well when the alkali is diflblved by water into a fluid, as ■when it is fufed by the aftion of fire. Vol. II. No. 33. 3 S T R Y. 7.3 Sulphur has lels affinity than any acid with the fixed alkalis: and therefore liver of fulphur may be decom¬ pounded by any acid whatever; which will unite with the fixed alkali, form therewith a neutral fait, and fe¬ parate the fulphur. If liver of fulphur be diffolved in water, and an acid poured thereon, the liquor, which was tranfparent be¬ fore, inftantly turns to an opaque white; becaufe the fulphur, being forced to quit its union with the alkali, lofes at the fame time the property of diflblving in wai¬ ter, and appears again in its own opaque form. The liquor thus made white by the fulphur is called milk of fulphur. If this liquor be fuffered to ftand ftill fbr fome time*, the particles of fulphur, now moft minutely divided, gra^ dually approach each other, unite, and fall infenfibly to the bottom of the veffel ; and then the liquor recoveis its tranfparency. The fulphur thus depofited on the bottom of the veffel is called the magifttry or precipi¬ tate fulphur. The names of magiftery and precipitate are alfo given to all fubltances whatever that are fepa¬ rated from another by this method ; which is the reafoa that we ufe the expreffion of precipitating one fubftance by another, to figntfy the feparating one of them by means of the other. 3. Of the Nitrous Acid. The nitrous acid conibined with certain abforbent . earths, fuch as chalk, marie, boles, forms neutral falts which do not cryftallize; and which, after being dried*, run in the air per deliquium. All thofe neutral falts which confift of the nitrous a- cid joined to an earth, may be decompofed by a fixed alkali, with which the acid unites, and deferts the earth; and from this union of the nitrous acid with a fixed al¬ kali refults a new neutral fait, which is called nitre, or falt-petre. This latter name fignifies the fait of ft one; and in fad, nitre is extraded from the ftones and plai- fter, in which it forms, by boiling them in water fatura* ted with a fixed alkali. Nitre ffioots in long cryftals adhering fideways to each other ; it has a faltifli tafte, which produces a fen- fation of cold on the tongue. This fait ealily diffolves in water; which, when it boils, takes up ftill a greater quantity thereof. It flows with a pretty moderate degree of heat, and continues fixed therein: but being urged by a brilk fire, and in the open air, it lets go fome part of its acid, and indeed flies off itfelf in part. The moft remarkable property of nitre, and that which charaderizes it, is its fulmination or explofion; the na¬ ture of which is as follows: When nitre touches any fubftance containing a pblog!- fton, and adually ignited, that is, red hot, it burfts out into a flame, burns, and is decompounded with much noife. In this deflagration the arid is diffipated, and totally feparated from the alkali, which now remains by itfelf. Indeed the acid, at leaft the greateft part of it, is by this means quite deftroyed. The alkali which is left when nitre is decompounded by deflagration, is called in T general 74 CHEMISTRY. general fixed nitre, and, mofe partipliiarly, nitre fixed by fuch and fuch a fnbftance as was ufed in the opera¬ tion. But if nitre be deflagrated with an inflammable fubftance containing the vitriolic acid, as fulphur, for in- ftance, the fixed fait produced by the deflagration-is not a pure alkali, but retains a good deal of the vitriolic a- cid, and, by combining therewith, hath now formed a neutral fait. The reafon why-nitre flames, and is decompounded in the manner above mentioned, when it comes in con- ta<5l with a phlogillon properly circumflanced, is, that the nitrous acid, having a greater affinity with the phlogi- llon than with the fixed alkali, naturally quits the latter to join with the former, and fo produces a kind of ful¬ phur, differing probably from the common fulphur, form¬ ed by the vitriofic acid, in that it is combuftible to fuch a degree, as to take, fire and be confumed in the very moment of its produition ; fo that it is impoflible to prevent its being thus deftroyed, and confequently im¬ poflible to fave it. In fupport of this opinion let it be considered, that the concurrence of the phlogifton is ab- fpiutely neceflary to produce this deflagration, and that the matter of pure fire is altogether incapable-of effect¬ ing it: for though nitre be expofed to the moft violent degree of fire, even that in the focus of the moff power¬ ful burning-glafs, it will not flame; nor will that effeCt ever happen till the nitre be brought into contaCt with a phlogiffon properly fo called, that is, the matter of fire exilting as a principle of fome body; and it is more¬ over neceffary that this phlogifton be actually on firei and agitated with the igneous motion, or elfe, that the nitre itfelf he red-hot, and fo penetrated with fire as to kindle any inflammable matter that touches it;. This experiment, among others, helps to flrew the difllnCtion that ought to be made between pure elementa¬ ry fire, and fire become a principle of bodies to which we have given the name of phlogifton. Before we leave this fubjeCt, we (hall obferve, that nitre deflagrates only with fueh fubftances as contain the phlogifton in its Jimpleft and pureft form; fuch as char¬ coal, fulphur, and the metailine fubftances ; and that, though it will not deflagrate without the addition of fome combuftible matter, it is neverthelefs the only known body that will burn, and make other combuftibles burn wit it, in clofe yeflels,. without the admiffion of frefh air. The nitrous acid hath not fo great an affinity with earths and alkalis as the vitriolic acid hath; whence it follows, that the vitriolic acid decompofes all neutral falts arifing from a combination of the nitrous acid with an earth or an alkali. The vitriolic acid expells .the ni¬ trous acid, unites with the fubftance which ferved it for a b'afis, and therewith forms a neutral fait, which is an alum, a felenites, or a vitriolated tartar, according to the nature of that bafis. The nitrous acid, when thus feparated from its bafis by the vitriolic acid, is named fpirit ofi nitre, or aqua fortis. If it be dephlegmated, or contain but little fu- pei fluous water, it exhales in reddifh vapours ; thefe va¬ pours being condenfed and collected, form a liquor of a brdwnifh yellow, that inceffantly emits vapours of the tame colour, and of a pungent difagrecable fmell. Thefe cbaracfters have procured it. the names of /making fpi¬ rit of nitre, and yello-w aqua fortis. This property in the nitrous acid of exhaling in vapours, fhews it to be lefs fixed than the vitriolic acid; for the latter, though ever fo thoroughly dephlegmated, never yields any va¬ pours, nor has it any fmell. 3. Of the Acid o/'Sea-salt. The acid of fea-falt is-fo called, becaufe it is iri fail obtained from fuch fea-falt as is ufed in our kitchens. It is not certainly known in what this acid differs from the vitriolic and the nitrous, with regard to its conftituent parts. When it is combined with abforbent earths, fuch as lime and chalk, it forms a neutral fait that does not cry- ftallize ; and, when dried, attracts the moifture of, the air. If tfie abforbent earth be not fully faturated with the marine acid, the fait thereby formed has the proper¬ ties' of a fixed alkali: And this is what made us fay, when we .were on the fubjeft of thofe falts, that they might be imitated by combining an earth with an acid. The marine acids like the reft, hath not fo great an af¬ finity with earths as with fixed alkalis. When it is combined with the latter, it forms a neu¬ tral fait which flioots into cubical cryftals. This fait is inclined to grow moift-in the air, and is confequently one of thofe which water diflblves in equal quantities, at leaft as to fenfe, whether it be boiling hot or quite cold. The affinity of this acid with alkalis and abforbent earths is not fo great as that of the vitriolic and nitrous acids: Whence it follows, that, when combined there¬ with, it may be feparated from them by either of thofe acids. The acid of fea-falt, thus difengaged from the fub¬ ftance which ferved it for a bafis, is called fpirit of fait. When it contains but little phlegm, it is of a lemon co¬ lour, and continually emits many white, very denfe, and very elaftic vapours; on which account it is named the fmoking or volatile fpirit of fait. Its fmell is not dif- agreeable, nor much unlike that of iaffron; but extreme- 1) quick and fuffocating when it fmokes. The acid of fea-falt, like the other two, feems to have a greater affinity with the phlogifton, than with fixed alkalis. We are led to this opinion by a very curious operation, which gives ground to think, that fea-falt may be decorapofed by the proper application of a fhbftance containing the phlogifton. From the marine acid; combined with a phlogifton, refults a kind of fulphur, differing from the common fort in many refpe&s ; but particularly in this property, that it takes fire of itfelf upon being expofed to the open air. This combination is called EngliJJj phofphorus, phofphorus of urine, becaufe it is generally prepared from urine, or only pbafphorus. This combination of the marine acid with a phlogifton is not eafily effedted ; becaufe it requires a difficult ope¬ ration in appropriated veffels. . For thefe reafons it does not always fucceed ; and phofphorus is fo fcarce and dear, that hitherto chemifts have not been able to make on it the experiments neceffary to difcover all its proper¬ ties. If phofphorus be fuffered to burn away in the air. C H E M a fmali quantity of an acid liquor may be obtained from it, which feems to be fpirit of fait, but either altered, or combined with feme adventitious matter; for it has fe- veral properties that ard not tp’ be found in the pure ma¬ rine acid; fuch as, leaving a fixed fufible fubftance be¬ hind it when expoled to a ftfong fire, and being eafily combined with the phlogifton fo as to reproduce a phof- phorus. Phofphorus refembles fulphur in feveral of its proper¬ ties : It is foluble m oils ; it melts with a gentle heat; it is very combuftibleit burns without producing foot; and its flame is vivid and bluifh. From what has been faid of the union of the acid of fea-falt with a fixed alkali, and of the neutral fait, refult- ing therefrom, it may be concluded, that this neutral fait is no other than the 'Common kitchen-falt. But it mult'be obferved, that the fixed alkali, which is the na¬ tural bafis of the common filt obtained from fea-water, is of a fort fomewhat differing from fixed alkalis in gene¬ ral, and hath certain properties peculiar to itfelf. For, x. The bafis of fea-falt differs from other fixed alkalis in this, that it cryflallizes like a neutral fait. 2. It does not grow moifl: in the air: On the contra¬ ry, when expofed to the air, it lofes part of the water that united with it in cryflallization, by which means its cryftals lofe their tranfpatency, become as it were mealy, and fall into a fine flour. 3. When combined with the vitriolic acid tp the point of faturation, it forms a neutral fait differing from vitri- olated tafiar, firfl, in the figuie of its cryilals, which are oblong fix-fided folids ; fecondly, in its quantity of water, which in cryftallizatio’n unites therewith in a much greater proportion than with vitriolated tartar ; whence it follows, that this fait diffolves in water more readily than vitriolated f tattar ; thirdly, in that it flows with a very moderate degree of lieat, whereas vittiokted tartar requires a very fierce one. If the acid of fea-falt be feparated from its bafis by means of the vitriolic acid, it is eafy to fee, that, -when the operation is finifhed, the fait we have been fpeaking, of muff be the refult. A famous chemiff, named Glau¬ ber, was the firft who extradited the fpirit of fait in this manner, examined the neutral fait refulting from his pro- cefs, and finding it to have fome fingular properties, called it \\\s fal juirnbite, or wonderful fait: On this ac¬ count it is ftill Called Glauber’s fat viirabile, or Glau¬ ber's fait. 4. When the bafis of the fea-falt is combined with the nitrous acid to the point of faturation, there refults a neutral fait, or a fort of nitre, differing from the common nitre, firft, in that it attradls the niqlftnre of the air pretty ftrongly; and this makes it .difficult to. cryftallize : fecondly, in the figure of its jcryflals, which are parallelepipeds ; and this has procured .it the name of quadrangular nitre.' Common fait, or the neutral fait formed by combining the marine acid with this particular fort of fixed alkali, has a tafte well known to everybody. The figure of its cryftals is exadlly cubical. It grows mbift in the air, and, when expofed to the fire, it burffs, before it melts, into I S T R Y. 75 many little fragments, with a crackling noife ; which is called the decrepitation of fea-falt. That neutral fait mentioned above, ■which is formed by combining the marine acid with a common fixed al¬ kali, and called fal febrifngum fylvii, hath alfo this pro- perty. India furnifhes us with a faline fubftance, known by the name of borax, which flows very eafily, arid then takes the form of glafs. It is of great ufe in facilitating the fufion of metallic fubftances. It poffeffes fome of the properties of fixed alkalis, which has induced certain chemifts to reprefent it, through miffake, as a pure fixed alkali. By mixing borax with the vitriolic acid, Mr Homberg obtained from it a fait, which fublimes in a certain de¬ gree of heat, whenever fuch a mixture is made. This fait has very lingular properties ; but its nature is not yet thoroughly underffood. It diffolves in water with great difficulty; it is not volatile, though it rifes by fublima- tion from the borax. According to Mr Rouelle’s obfer- vation, it rifes then only by means of the water which carries it up ; for when once made, it abides the 'fierCelt fire, flows and vitrifies juft as borax does, provided cafe be taken to free it previoufly from moifture by drying it properly. Mr Homberg called it fedative fait, on ac¬ count of its medical effedls. The fedative fait hath the appearance, and fome of the properties, of a neutral fait; for it fhootsinto cryftals, and does not change the colour of violets : but it ads the part of an acid with regard to- alkalis, uniting with them to the point of faturktion, khd tfiereby forming a true neutral fait. It alfo ads, like the acid of vitriol, on all neutral falls ; that is, it difehargeb the acid of fuch as have not the vitriolic acid in their compofition. Since Mr Homberg’s time it hath been difeovered, that a fedative fait may be made either with the nitrous or, with the marine acid ; and that fublimation is not fie- ceffary to extrad it from the borax, but that it may be obtained by cryftallization only. For this latter difeo- very, we are indebted to Mr Geoffrey, as we are to Mr Lemery for the former. Since that time M. Baron d’ Henouville, an able che-' miff, hath ftiewn that a fedative fait may be obtained by rhe means of vegetable acids ; and hath lately deraon- ftrated, that the fedative fait exifls adually and perfedly in the borax, and that it is not produced by mixing acids- with that faline fubftance, as it feetns all the chemifts be¬ fore him imagined. This he proves convincingly from- his analyfis of borax, (which thereby appears to be no¬ thing elfe but the fedative fait united with that fixed al¬ kali which is the bafis of fea-falt) and From his regetie-, rating the fame borax by uniting together that alkali and the fedative fait: a proof the moll complete that can- pofllbly be produced in natural philofophy, and equiva¬ lent to dernonftration itfelf. In order to finifh what remains to be faid upon the fe¬ veral forts of faline fubftances, we ftiould now fpeak of the acids obtained from vegetables and animals, and alfo of the volatile alkalis ; but, feeing thefe faline fubftances differ from thofe of which we have already treated, only C H E M as they are varloufly altered by the unions they have con- trafted with certain principles of vegetables and animals, of which nothing has been yet faid, it is proper to defer being particular concerning them, till we have explained thofc principles. 0/ Lime. Any fub'dance whatever, that has been roafled a con- fiderable time in a ftrong fire without melting, is com¬ monly called a calx. Stones and metals are the princi¬ pal fubjefts that have the property of being converted in¬ to calces. We (hall treat of metalline calces in a fubfe- quent chapter, and in this confine ourfelves to the calx of Jione, known by the name of lime. In treating of earths m general, we obfervedthat they may be divided into two principal kinds ; one of which a&ualiy and properly flows when ekpofed to the action of fire, and turns to glafs ; whence it is called a fuftile or vitrifiable earth • the other refifts the utmofl force of fire, and is therefore faid to be an unfufiblt or unvitrifi-, able earth. The latter is alfo not uncommonly called calcinable earth ; though fundry forts of unfufible earths are incapable of acquiring by the a<5Hon of fire all the qualities of calcined earth, or lime properly fo called : fuch earths are particularly diftinguifhed by the denomi¬ nation of refrattory earths. As the different forts of flones are nothing more than compounds of different earths, they have the fame pro¬ perties with the earths of which they are compofed, and may, like them, be divided into fufible or vitrifiable, and unfufible or calcinable. The fufible ftones are generally denoted by the name of flints ; the calcinable (tones, a- gain, are the feveral forts of marbles, cretaceous (tones, thofe commonly called free-ftones, tec. fome of which, as they make the belt lime, are, by way of eminence, called lime-Jlones. Sea-fhells alfo, and (tones that a- bound with foflile (hells, are capable of being burnt to lime. All thefe fubltances being expofed for a longer or (hotter time to the violent action of fire, are faid to be calcined. By calcination they lofe a confiderable part of their weight, acquire a white colour, and become friable, though ever fo folid before ; as, for inftance, the very hardeft marbles. Thefe fubftances, when thus calcined, take the name of quick-lime. Water penetrates quick-lime, and ru(hes into it with Yaft aftivity; If a lump of newly calcined lime be thrown into water, it inftantly excites almoft as great a noife, e- bullition, and fmoke, as would be produced by a piece of red-hot iron ; with fuch a degree of heat too, that, if the lime be in due proportion to the water, it will fetfire to combuftible bodies ; as hath unfortunately happened to veffels laden with quick lime, on their fpringing a fmall leak. As foon as quick-lime is put into water, it fwells, and falls afunder into an infinite number of minute particles : in a word, it is in a manner diffolved by the water, which forms therewith a fort of white pafte called flack¬ ed lime. If the quantity of water be confiderable enough for I S T R Y. the lime to form with it a white liquor, this liquor is called lac calcis; which, being left fome time to fettle, grows clear and tranfparent, the lime which was fufpend-. ed therein and occafioned its opacity fubfiding to the bottom of the veffel. Then there forms on the furface of the liquor a cryftalline pellicle, fomewhat opaque and dark coloured, which being (kimmed off is reproduced! from time to time. This matter is called cremor calcis. Slacked lime gradually grows dry, and takes the fornj of a folid body, but full of cracks and deftitute of firm- nefs. The event is different when you mix it up, while yet a pafte, with a certain quantity of uncalcined ftony matter, fuch as fand for example : then it takes the name of mortar, and gradually acquires, as it grows drier and older, a hardnefs equal to that of the heft (tones. This is a very (jugular property of lime, nor is it eafy to ac¬ count for it; but it is a beneficial one, for every body knows the ufe of mortar in building. Quick-lime attraAs the moifture of the air in the fame manner as concentrated acids and dry fixed alkalis, but not in fuch quantities as to render it fluid : it only fails into extremely fmall particles, takes the form of a fine- powder, and the title of lime flacked in the air. Lime once (lacked, however dry it may afterwards ap¬ pear, always retains a large portion of the water it h d imbibed ; which cannot be feparated from it again but by means of a violent calcination. Being fo recalcined it re¬ turns to be quick-lime, recovering all its properties.. Befides this great affinity of quick-lime with water, which difeovers a faline character, it has feveral other faline properties, to be afterwards examined, much re- fembling thofe of fixed alkalis. In chemiftry it afts very nearly as thofe falts do, and may be confidered as hold¬ ing the middle rank between a pure abforbent earth and a fixed alkali; and this hath induced many chemifts to. think that lime contains a true fait, to which all the pro-, perties it pofieffes in common with falts may be attri¬ buted. But as the chemical examination of this fubjedt hath long been neglefted, the exiftence of a faline fubftance in lime hath been long doubtful. Mr du Fay was one of the firft who obtained a fait from lime, by lixiviating it with a great deal of water, which he afterwards evapo¬ rated. But the quantity of fait he obtained by that means was very fmall; nor was it of an alkaline nature,, as one would think it fhould have been, confidering the properties of lime. Mr du Fay did not carry his expe¬ riments on this fubjeA any further, probably for want of time; nor did he determine of what nature the fait was. Mr Malouin had the curiofity to examine this fait of lime, and foon found that it was nothing elfe but what was above called cremor calcis. He found moreover, that, by mixing a fixed alkali with lime-water, a vitriol- ated tartar was formed ; that, by mixing therewith an alkali like the bafis of fea-falt, a Glauber’s fait .was pro¬ duced ; and, laftlv, by combining lime with a fubftance abounding in phlogifton, he obtained a true fulphur. Thefe very ingenious experiments prove to a demonftration, that the vitriolic acid conftitutes the fait of lime ; for, as hath been (hewn, no other acid is capable of forming fuch combi- C H E M combinations. On the other hand, Mr Malouiri, having forced the vitriolic acid of this fait to combine with a phlogifton, found its bafis to be earthy, and analogous tp that of the felenites : whence he concluded, that the fait of lime is a true neutral falt„ of the fame kind as the felenites. Mr Malouin tells us he found feveral other falts in lime. But as none of them was a fixed alkali, and as all the faline properties of lime have an affinity with thofe of that kind of fait, there is great reafon to think that all thole falts' are foreign to lime, and that their union with it is merely accidental. Lime unites with all acids, and in conjunftion with them exhibits various phenomena. • The vitriofie acid poured upon lime diffolves it with effervdfcence and heat. From this mixture there exhales a great quantity of vapours, in fmefl and colour perfefaid above, de¬ prives the gold of its fulminating quality. Of Silver. Next t® gold, filver is the mod perfeiS metal. Like gold, it refills the utmoft violence of fire, even that in the focus of a btirning-glafs. However, it holds only the fecohd place among metals; becaufe it is lighter-than gold by almoll one half; is alfo fomewhat lefs duftile; and lallly, becaufe it is a died upon by a greater number of folvents. Yet filver hath one advantage over gold, namely that of being a little harder; which makes it alfo more fo- norous. This metal, like gold, begins to flow when it is fo thoroughly penetrated by the fire as to appear ignited like a live coal. While this metal is in fufion, the immediate contact of the vapour of burning coals deprives it almoll entirely of its malleability, in the fame manner as we obferved happens to gold : but both thefe metals eafily recover that property by being melted with nitre. The nitrous acid is the true folvent of filver, and be¬ ing fomewhat dephlegmated will very readily and eafily .take up a quantity of filver equal in weight to itlelf. Silver thus combined with the nitrous acid forms a metallic fait which Ihoots into cryllals, called by the name of lunar cryjlals, or cryftals of fiver. Thefe cryllals are mod violently caullic: applied to the flcin, they quickly afFed it much as a live coal would; they produce a blackilh efchar, corroding and' entirely . dellroying the parts they touch. Surgeons ufe them to eat away the proud fungous flelh of ulcers.. As filver u- nited with the nitrous acid hath the property of blacken¬ ing all animal fubltances, a folution of this metallic fait is employed to die hair, or other animal, matters, of a beautiful and durable black. Thefe cryllals flow with a very moderate heat, and even before they grow red. Being thus melted, they form a blackilh mafs; and in this form they are ufed by furgeons, under the title of lapis infcrnalis, infernal feme, ''ox filver cauflic. Silver is alfo dilfolved by the vitriolic acid: but then- the acid mud be concentrated, and in quantity double the weight of the filver: nor will the folution fucceed without a confiderable degree of heat. Spirit, of fait and a Qua regis, as wellas the otlier a- s T R Y. 79 cids, are incapable of diflblving this metal, at lead in the ordinary way. Though filver be not foluble in the acid of fea-falt, nor eafily in the acid of vitriol, as hath jull been obfer¬ ved, it doth not follow, that it hath but a weak affinity with the latter, and none at all with the former: on the contrary, it appears from experiment, that it hath with thefe two acids a much greater affinity than with the a- cid of nitre : which is Angular enough, confidering the facility with which this lalt acid dillblves it. The experiment which proves the fadt is this. To a folution of filver in the nitrous acid add the acid eithei' of vitriol or of fea-falt, and the filver will inflantly quit its nitrous folvent to join with the fuperadded acid. Silver thus united with the vitriolic or the marine a- cid is lefs foluble in water than when combined with the nitrous acid : and for this reafon it is, that when either, of thefe two acids is added to a folution of filver, the li¬ quor immediately becomes white, and a precipitate is formed, which is no other than the filver united with the precipitating acid. If the precipitation be elFefted by the vitriolic acid, the precipitate will difappear upon adding a fufficient quantity of water, becaufe there will then be water enough to diflblve it. But the cafe is not the fame when the precipitation is made by the marine acid : for filver combined therewith is fcarce foluble in water. This precipitate of filver procured by means of the ma¬ rine acid is very eafiiy fufed, and when fufed changes to a fubflance in fome meafure tranfparent and flexible; which hath occafioned it to be called by the name of luna cornea. If it be propofed to decompound this lima cornea, that is, to feparate the marine acid from, the filver with which it is united, the luna cornea mud be melted along with fatty and abforbent matters, with wliich the acid will unite, and leave the metal exceeding pure. It muft be obferved, that if, inftead of the: marine a- cid, fea-falt in fubflance be added to a fohmon of filver in the nitrous acid,, a precipitate is alfo produced, which by fufion appears to be a true luna cornea. The reafon is, that the fea-falt is decompofed by the nitrous acid, which feizes its balls, as having a greater affinity there¬ with than its own acid hath ; and this acid being con- fequently difengaged and fet at liberty unites with the filver, which, as has been fhewn, has greater affinity with it than with the nitrous, acid. This is an inflance of decompofition effected by means of one of thofe double affinities mentioned in the feventh propofition concerning affinities* From what hath been already faid it i. clear, that all thefe combinations of filver with acids may be decom¬ pounded by abforbent earths and by fixed alkalis ; it be¬ ing a general law with regard to all metallic fubflances. Silver, when feparated by.thefe means fiom the acids in which it was diflolved, requires nothing but fimnle fu¬ fion to reflare it to its ufual form ; becaufe it doeV not any more than gold, lofe its phlogifton. by thofe folutions and precipitations. Silver unites with fulphur in fufion-. If this metal ke¬ enly made red-hot in a crucible, and fulphur be then ad- ded,. 8b C H E M I ckd, it immediately flows ; the fulphur a ding as a flux to it. Silver thus united with fulphur forms a mafs that may be cut, is half malleable, and hath nearly the co¬ lour and confidence of lead, If this fulphurated filver be kept a long time in fufion, and in a great degree of heat, the fulphur flies off and leaves the filver pure. But if the fulphur be evaporated Sjra violent heat, it carries oft' with it part of the filver. Silver unites and mixes perfectly with gold in fufion. The two metals thus mixed form a compound with pro¬ perties partaking of both. Metallurgifts have hitherto fought in vain for a per- fedlly good and eafy method of feparating thefe two me¬ tals by the dry . it follows, that when the vitrification of the imperfeCt me¬ tals is effected by its means, all thofe vitrified matters together penetrate the veffel containing the fufed metal¬ line mafs, difappear, and leave only the gold and filver perfectly C H E M perfe&ly pure, and freed, as far as is poflible, from all admixture of heterogeneous parts. The better to promote the reparation of fuch parts, it is ufual to employ in this procefs a particular fort of fmall crucibles, made of the allies of calcined bones, which are exceedingly porous and eafily pervaded. They are called cupels, on account of their figure, which is that of a wide¬ mouthed cup : and from hence the operation takes its name; for when we refine gold and filver in this manner, we are faid to cupel thofe metals. It is eafy to perceive, that the more lead is added, the more accurately will the gold and filver be refined ; and that fo much the more lead ought to be added as the perfect metals are alloyed with a greater proportion of the imperfedt. This is the moft fevere trial to which a perfedt metal can be put, and confequently any metal that Hands it may be fairly con- fidered as fuch. In order to denote the finenefs of gold, it is fuppofed to be divided into twenty-four parts called carats ; and gold, which is quite pure and free from all alloy, is faid to be twenty-four carats fine; that which contains ^ •part of alloy is called gold of twenty-three carats ; that which contains of alloy is but twenty-two carats ; and fo on. Silver again is fuppofed to be divided into twelve parts only, which are called penny-’weights; fo that when abfolutely pure it is faid to be twelve penny-weights fine; when it contains ^ of alloy, it is then called eleven penny-weights fine; when it contains -rT of alloy, it is called ten penny-weights fine ; and fo on. In treating of copper, we promifed to (hew under the article of lead how to feparate it from iron. The pro¬ cefs is founded on that property of lead which renders it incapable of mixing and uniting with iron, though it rea¬ dily diflblves all other metalline fubftances. Therefore . if you have a mafs compounded of copper and iron, it mull be fufed with a certain quantity of lead, and then the copper, having a greater affinity with lead than with iron, will defert the latter and join the former, which being incapable of »ny union with iron, as was faid, will wholly exclude it from the new compound. The next point is to feparate the lead from the copper ; which is done by expofing the mafs compounded of thefe two me¬ tals to a degree of fire llrong enough to deprive the lead of its metalline form, but too weak to have the fame ef¬ fect on the copper : and this may be done, fince of all the imperfect metals lead is, next to tin, the eafieft to be cal¬ cined, and copper, on the contrary, refills the greatell force of fire longeft, without lofing its metalline form. Now what we gain by this exchange, viz. by feparating copper from iron, and uniting it with lead, confills in this, that as lead is calcined with lefs fire than iron, the cop¬ per is lefs expofed to be dellroyed : for it mull be ob- ferved, that, however moderate the fire be, it is hardly poffible to prevent a certain quantity thereof from being calcined in the operation. Lead melted with a third part of tin forms>a compound, ^vhich being expofed to a fire capable of making it tho¬ roughly red hot, fwetls, puffs up, feems in fome fort fo take fire, and is prefently calcined. Thefe two metals mixed together are much fooner calcined than either of 'them feparately. Von. II. No. 33. 3 I S T R Y. 85 Both lead and tin are in fome meafure affedied by wa¬ ter, and by a moill air ; but they are both much lefs fub- jedt than iron or copper to be corroded by thefe folvents, and of courfe are much lefs liable to ruff. The vitriolic acid adts upon and dilfolves lead much in the fame manner as it doth filver. The nitrous acid diffolves this metal with much eafe, and in great quantities ; and from this Ablution a fmail portion of mercury may be obtained. When this folution of lead is diluted with a good deal of water, the lead precipitates in the form of a white powder ; which happens becaufe the acid is rendered too weak to keep the lead diflblved. If this folution of lead be evaporated to a certain de¬ gree, it ffioois into cryftals formed like regular pyramids with fquare bafes. Thefe cryftals are of a yellowiffi co¬ lour, and of a faccharine tafte : they do not eafily diffolve in water. This nitrous metalline fak has the Angular property of detonating in a crucible, without any addi- tament, or the contadl of any other inflammable fubftance. This property it derives from the great quantity of phlo- gifton contained in, and but loofely connected with the lead, which is one of its principles. If fpirit of fait, or even fea-falt in fubftance, be added to a folution of lead in the nitrous acid, a white precipi¬ tate immediately falls ; which is no other than the lead united with the marine acid. This precipitate is extreme¬ ly like the precipitate of filver made in the fame manner; and that being called luna cornea, hath occafioned this to be named plumbum corneum. Like the luna cornea, it is very fufible, and, being melted, hardens like it into a kind of horny fubftance : it is volatile, and may be re¬ duced by means of inflammable matters combined with alkalis. But it differs from the luna cornea in this chiefly, that it dilfolves eafily in water ; "whereas the lu¬ na cornea, on the contrary, diffolves therein with great difficulty, and in a very fmall quantity. As this precipitation of lead from its folution in fpirit of nitre is procured by the marine acid, lead is thereby proved to have a greater affinity with the latter acid than with the former. Yet, if you attempt to diffolve lead di- reftly by the acid of fea-falt, the folution is not fo eafily effedied as by the fpirit of nitre, and it is always imper- fe8 known to have a greater affinity than the marine acid with alkalis, and even with the bafts of fea-falt i tie If. . Yet arfenic may be combined with the bafis of fea-falt, and a neutral fait thereby obtained, like that which re- fults from the decompofition of nitre by arfenic : but for that purpofe a quadrangular nitre mull be firft prepared, and arfenic applied thereto as to common nitre. . The fait produced by uniting arfenic with the bafis of fea-falt very much refembles the neutral fah of arfenic above treated of, as well in the figure of its cryftals as in its feveral properties. Arfenic prefents another fingular phenomenon, both with the alkali of nitre and with that of fea-falt; which is, that,if it be combined with thefeTales in a fluid (late, it forms with them a faline compound, quite different from the neutral fairs of arfenic which refults from the decomppfition of nitrous falts. ■ This faline compound, called liver of arfenic, takes up a much greater quantity of arfenic than is necefl’ary for the perfed; faturation of the alkali. It has th.e ap¬ pearance of a glue, which is fo much the thicker the more arfenip it contains. Its fmell is.difitgreeable.; it attracts the moiflure of the air, and does not cryflallize; it is eafily decompounded by any acid whatever, which precipitates the arfenic arid unites with the alkali. Laffv ly, the jeffeidsit produces on metallic folutions are differ¬ ent. from thofe offour neutral arfenical falts,. Arfenic, is eafily reduced to a regulus. It need only be mixed with any matter containing the phlogifton, and by the help of a moderate heat, a true regulus will fub- l .ne. This regulus,is very volatile, and calcines with the grcatell eafe; which is the reafon why it cannot be Obtained but, in frnall quantities; and alfo why, in order to obtain maffes of it, fome have thought of adding thereto fpme metal with which it has a great affinity, fuch as copper or iron ; becaule, by joining with the me¬ tal, it is partly fixed arid reffrained from flying off. But it is plain the regulus obtained by this means is not pure, as it mull partake corifiderahly of the metal em¬ ployed. Arfenic readily unites with fulphur, and rifes with it in.a yellow compound called drpiment. Sulphur cannot be feparated from arfenic but by the intervention of two bodies only; to wii, a fixed alkali and mercury. The property which mercury poffeffes of feparating fulphur from arfenic is founded on this, that thefe two metallic fubffances are incapable of contradling any uni¬ on; whereas, though moft of the other metals and femi- metals have a greater affinity with fulphur than mercury hath, nevertbelefs they are all unable to decompound orpiment; becaufe fome of them have as great an affinity with arfenic as with fulphur ; others have no affinity with either; and laftly, fulphur hath as great an affinity with arfenic as with any of them. It muff be obferved, that, if fixed alkalis be employed to purify arfenic in this manner, no more muft be ufed than is neceffary to abforb the fulphur or the phlogifton, of which alfo it is their nature to deprive arfenic; for o-. therwife, as it has been ftiewn that arfenic readily unites I S T R Y. with alkalis, they would abforb a confiderable quantity thereof. Of Oil in general. Oil is an un&uous body, which burns and con- fumes with flame and fmoke, and is not foluble in water. It confifts of the phlogifton united with water by means of an acid. There is, moreover, in its compofition a cer¬ tain proportion of earth, more or lefs according to each feveral fort of oil. The inflammability of oil evidently proves that it con¬ tains the phlogiftoa. That an acid is one of its confti- tuent principles many experiments demonftrate, of whirih thefe are the chief: If certain oils be long' triturated with an alkaline fait, agd the alkali afterwards diffolved in water, cryftals of a true neutral fait will be ptoducrid: fome metals, and particularly copper, are corroded arid rufted by oils,1 juft as they are by acids: again, acid cryftals are found in fome oils that have been long kept. This acid in oil ferres undoubtedly to unite its phlogi- ftori with it's water ;. becaufe thefe two fubftahees havritig no affinity with each other cannot be united without5the intervention of fuch a medium as an acid, which has an affiriity with* both. As to the exiftence of water in oils, it appears plainly when they are decompofed by repeated diftillatiqns, efpecially after mixing them with abforbent earths. Lafftly, when an oil is deftroyed by .burning, a certaiirquantity of earth is conftantly left behind. Oils expofed to the fire in clofie yeflels pafs over almoft wholly from the containing.veffel into,any rither applied to receive them. There remains, however, a fmall quantity of black matter, which is extremely fixed5, and continues unalterable as long as it has no communication with the external air, be the force of the-jire ever fo vio¬ lent. This matter is no other than part of the phlofti- fton of the oil united with its moft liked and groffeft: earth ; and this is what we called charcoal, or plainly a coal. Of Charcoal. When oil happens to be united to much earth, as it is in vegetable and animal bodies, it leaves-a confiderable quantity of coal or charred matter. This coal, expofed to the fire in the open air, burns and waftes, but without blazing like other combuftible matters: there appears only a fmall bluifti flame, but not the leaft fmoke. Moft commonly it only glows and fparkles, and fo gradually falls into alhes, which are nothing but the earth of the body combined with an alka¬ line fait in burning. This alkaline fait may be feparated from the earth, by lixiviating the allies with water, which diffolves all the fait, and leaves the earth quite pure. Charcoal is unalterable and indeftruflible by any other body but fire; whence it follows, that when it is not actually kindled and ignited, the moft powerful agents, Tuch as the acids, though ever fo ftrong and concentra¬ ted, have not the leaft effeA on it. The cafe is otherwife when it is lighted, that is, when its phlogifton begins to feparate from its earth; for then the pure acid of vitriol being joined therewith contrails C H E M an instantaneous union with its phlogifton, and evaporates in a volatile fulphureous fpirit. If the vitriolic acid, in- ftead of being applied quite pure, be firlt clogged with fome bafis, efpecially an alkaline one, it quits that bafis, enters into a more intimate union with the phlogifton of the burning coal, and fo forms an adiual fulphur, with which the alkali now unites and forms a hepar. The pure acid fea-falt hath not been obferved to aft in the lead upon charcoal, efpecially when it is not on fire. But when this acid is incorporated with an alkaline or metallic bafis,' and combined according to a peculiar procefs with burning charcoal, it in like manner quits its bafis, unites with the phlogifton, and therewith forms a phofphorus. Nor has the pure nitrous acid any effeft on a charred coal, even when ignited: and fo far is it from being able to kindle a cold one, that when poured on a live one, it extinguifhes it like water. But when this acid 'is ;i ;ited with a bafis, it quits it, rapidly as foon as it touches ^ burning coal, and rulhes violently into an uni- .on A'lth the phlogifton thereof. From this union there probably arifes, as we faid before, a kind of fulphur or phofphorus, which is fo inflammable as to be deftroyed by the fire the very moment it is generated. The acids of nitre and vitriol aft upon oils ; but very differently, according to the quantity of phlegm they con¬ tain. If they be awakened with much water, they have no efFeft at all upon oils : if they contain little water, or be dephlegmated to a certain degree, they dilfolve them with heat, artd with them form compounds of a thick confiftence. Acids thus combined in a confiderable pro¬ portion with oils render them foluble in water. r Of Soap. Alkalis alfo have the fame property. When an oil is combined with an acid, or an alkali, in fuch a manner that the compound refulting from their union is foluble in water; fuch a compound may in general be called foap. Soap itfelf hath the property of rendering fat bodies in fome meafure foluble in water; on which account it is very ufeful for fcouring or cleanfing any thing greafy. Oily and faline fubftances, combined together, obferve the fame general rules as all other combinations; that is, they mutually communicate the properties belonging to each : thus oils, which naturally are not foluble in water, acquire by their union with faline matters the property of diflblving therein ; and falts lofe by their conjunftion with oils part of their natural tendency to incorporate with water; fo that while they ferve to conftitute foap, they do not, as before, attraft the moifture of the air, foe. and in like manner, as they are not inflammable, they confiderably leflen the inflammability of the oils combined with them. Acid fqaps are decompounded by alkalis, as alkaline foaps are by acids, according to the general rules of affi¬ nities. . The acids of nitre and vitriol, when highly concen¬ trated, diflblve oils with fuch violence as to heat them, make them black, burn them, and even fet them on fire. How fea-fealt affefts oils is not yet fufficiently afeertained. All oils have the property of diflblvuig fulphur ; which Vol. II. No. 34. • 3 I S T R Y. 93 is not at all furprifing, feeing each of its component prin¬ ciples hath an affinity with oil. It is alfo a property common to all oils tp become more fluid, fubtile, light, and limpid, the oftener they are di- ftilled. On the contrary, by being incorporated with faline fubftances they acquire a greater confiftence, and fometimes form compounds that are almoft folid. Of the federal forts of Oils. Oils are'diftinguiffied by the fubftances from which they are drawn : and as oils are extrafted from minerals, from vegetables, and from animals, there are of courfe mineral, vegetable, and animal dils. (?/ Mineral Oils. In the bowels of the earth we find but one fort of oil, called pitr«leum : Its fmell is Itrong, and not difagree- able, and its colour fometimes more, fometimes lefs yel¬ low. There are certain mineral fubftances which yield by diftillation a great deal of oil very like petroleum. This fort of fubftance is called a bitumen, and is, indeed, nothing but an oil rendered confiftent and folid by beinw combined with an acid ; as appears from hence, that, by uniting petroleum with the acid of vitriol, we can pro¬ duce an artificial bitumen very like the native. f tartar. The fame liquor which produces this cream, and in which the purified tartar is diflblved, being fet to cool, yields a great number of white femi-tranfparent cryftals, which are Called cryftttls of tartar. 'The cream and the cryftals of tartar are therefore no other than purified tartar, and differ from each other in their form only. Though the cryftals of tartar have every appearance of a neutral fait, yet they are far from being fuch; for they have all'the properties of a true acid, which fcarce differs from that of vinegar, except that it contains lefs water* and more earth and oil; to which it owes its folid form, as well as its property of not being foluble in water without much difficulty: for a very great quantity of wa¬ ter is requifite to keep the bryftals of tartar in folution; and it muft moreover be boiling hot; otherwife as foon as it cools moft of the tartar diffolved in it feparates from the liquor, and falls to the bottom in the form of a white powder. Tartar is decompofed by calcination in the open fire. All its oily parts are confumed or diffipated in fmoke, together with moft of its acid. The other part of its acid, uniting intimately with its earth, forms a vent ftrong and very pure fixed alkali, called fait of tartarl It will be (hewn in its proper place, that almoft every vegetable matter, as well as tartar, leaves a fixed alkali in its affies : yet tartar has thefe peculiar properties; flrft, it affumes an alkaline charafter even when burnt or calcined in clofe veffels, whereas other fubftances ac¬ quire it only by being burnt in the open air; (econdly, the alkali of tartar is (trOnger and more faline than almoft any that is obtained from other matters. This alkali, when thoroughly calcined, powerfully at- trafts the moifture of the air, and melts into an unftu- cus alkaline liquor, improperly called oil of tartar per deliquium. This is the alkali generally ufed in,making the terra foliata, mentioned under the head of vinegar; for which reafon this combinationis called terrafoliata tartari. Cryftals of tartar combined with alkali of tartar pro¬ duce a great effervefcence while they are mixing, as all acids ufually do, and if the combination be brought ex¬ actly up to the point of faturation, a perfedtlj neutral S T R Y. fait is formed, which (hoots into fcryftals, and eafily dif- folves in water; and this hath procured it the name of foluble tartar. It is alfo called the vegetable fait, as being obtained from vegetables only; and again tartarifed tartar, becaufe it confifts of the acid and the alkali of tartar combined together. Cryftals of tartar combined with alkalis procured from the alhes of fea-weeds, fuch as foda, which alkalis re- femble the bafis of fea-falt, form likewife a neutral fait, which cryftallizes well, and diftblves eafily in water. This fait is another fort of foluble tartar. It is called Saignette's fait, from the inventor’s name. Tartar likewife diffolves the abforbent earths, as lime, chalk, and with^them forms neutral falts which are foluble in water. It^even attacks metallic bodies, and when combined with them becomes foluble. A foluble tartar for medical ufe is prepared with cryrtals of tartar and iron : the metallic fait thereby produced hath the name of chalybeated foluble tartar. This fait attracts the moifture of the air, and is one of thofe which do not cryftallize. Cryftallized tartar ads alfo upon feveral other metallic fubftances : for inftance, it diffolves the regulus, liver, and glafs of antimony, and thence acquires an emetic qua¬ lity : It is then called fibiated, or emetic tartar. It likewife diffolves lead, and therewith forms a fait which, in the figure of its cryftals, refembles tartarifed tartar. It is very extraordinary, that tartar, which of itfelf is not foluble in water, (hould be foluble therein when be¬ come a neutral fait by uniting either with alkalis or with abforbent earths, or even with metals. All the foluble tartars are eafily decompounded by expofing them to a certain degree of neat. In diftillation they yield the fame principles tyhich are obtained from tartar ; and what re¬ mains fixed in the fire, after they are thoroughly burnt, is a compound of the alkali which tartar naturally pro¬ duces, and of the alkaline or metallic fubftance with which it was converted into a neutraffalt. As cryftal of tartar is the weakeft of all acids, on ac¬ count of the oily and earthy matters with which it is com¬ bined, foluble tartars are decompounded by all the acids ; by any of which cryftal of tartar may be feparated from the fubftance that ferves it for a bafis and renders it a neutral fait. Of the Putrid Fermentation, or Putrefatfion. Every body which Hath gone through the two ftages of fermentation above deferibed, that is, the fpirituous • and the acetous fermentation, being left to itfelf in a due degree of warmth, which varies according to the fubjeft^ advances to the laft ftage of fermentation ; that is, to pu¬ trefaction. When a body is in a putrefying (late, it is eafy to dif- cover, by the vapours which rife from it, by the opacity wrich invades it, if a pellucid liquor, and frequently even by a greater degree of heat than is found in the two o- ther forts of fermentation, that an inteftine motion is be¬ gun among its conftituent parts, which lafts till the whole be entirely putrefied. The effect of this inteftine motion is to break the union. C H E M union, and change the difpofition, of the particles con- ftituting the body in which it is excited, and to produce a new combination. If we examine a fubftance that has undergone putre- faftion, we fliall foon perceive that it contains a principle 'which did not exift in it before. If this fubftance. be di- ftilled, there rifes firft, by means of a very gentle heat, a faline matter which is exceedingly volatile, and affedts the organ of fmelling brifkly and difagreeably. Nor is the aid of diftillation necefla, y to difcover the prefence of this produdt of putrefa&ion : it readily manifefts itfelf in moft fubftances where it exifts, as any one may foon be convinced by obferving the different fmell of frefh and of putrefied urine ; for the latter not only affedls the nofe, but even makes the eyes fmart, and irritates them fo as to draw tears from them in abundance. This faline principle, which is the produdt of putre- fadtion, when feparated from the other principles of the body which affords it, and colledted by itfelf, appears either in the form of a liquor, or in that of a concrete fait, according to the different methods ufed to obtain it. In the former ftate it is called a volatile urinous fpirit; and in the latter a volatile urinous fait. The qualifica¬ tion of urinous is given it, becaufe a great deal thereof is generated in putrefied urine, to which it communicates its fmell. It goes alfo by the general name of a volatile al¬ kali, whether in a concrete or in a liquid form. The enumeration of its properties will fhew why it is called an alkali. Volatile alkalis, from whatever fubftance obtained, are all alike, and have all the fame properties ; differing on¬ ly according to their degrees of purity. The volatile al¬ kali, as well as the fixed, confifts of a certain quantity of acid combined with, and entangled by a portion of the earth of the mixt body from which it was obtained ; and on that account it has many properties like thofe of a fixed alkali, But there is moreover in its compofition a con- fiderable quantity of a fat or oily matter, of which there is none in a fixed alkali; and on this account again there is a great difference between them. Thus the volatility of the alkali produced by putrefaction, which is the prin¬ cipal difference between it and the other kind of alkali, whofe nature it is to be fixed, muft be attributed to the portion of oil which it contains : for there is a certain method of volatilizing fixed alkalis by means of a fatty fubftance. Volatile alkalis have a great affinity with acids, unite therewith rapidly, and with ebullition, and form with them neutral falts, which ffioot into cryftals, but differ from one another according to the kind of acid employed in the combination. The neutral falts which have a volatile alkali for their bafis are in general called ammoniacal falts That whofe acid is the acid of fea-fak is called fal ammoniac. As this was the firft known, it gave name to all the reft. Great quantities of this fait are made ip Egypt, and thence brought to us. They fublime it from the foot of covv’s dung, which is the fuel of that country, and con¬ tains fea-fak, together with a volatile alkali, or at leaft the materials proper for forming it; and confequently all I S T R Y. the ingredients that enter into the compofition of fal am¬ moniac. The neutral faks formed by combining the acids of nitre and of vitriol with a volatile alkali, are called, after their acids, nitrous fal ammoniac, and vitriolic fal am¬ moniac : The latter, from the name of its inventor, is alfo called Glauber’s fecret fal ammoniac. A volatile alkali, then, has the fame property as a fixed alkali with regard to acids ; yet they differ in this, that the affinity of the former with acids is weaker than that of the latter : and hence it follows, that any fal ammo¬ niac may be decompounded by a fixed alkali, which will lay hold of the acid, and difcharge the volatile alkali. A volatile alkali will decompound any neutal fait which has not a fixed alkali for its bafis ; that is, ajl fuch as confift of an acid combined with an abforbent earth or a metallic fubftance. By joining with the acids in which- they are diffolved, it difengages the earths or metallic fubftances, takes their place, and, in conjundion with their acids, forms ammoniac falts. Hence it might be concluded, that, of all fubftances, next to the phlogifton and the fixed alkalis, volatile al¬ kalis have the greateft affinity with acids in general. Yet there is fome difficulty in this matter : for abforbent earths and feveral metallic fubftances are alfo capable of decompounding ammoniacal falts, difcbarging their, vo¬ latile alkali, and forming new compounds by uniting with their acids. This might induce us to think that thefe fubftances have nearly the fame affinity with acids. But it is proper to obferve, that a volatile alkali de¬ compounds fuch neutral faks as have for their bafis either an abfbrbent earth or a metallic fubftance, without the. aid of fire ; whereas abforbent earths or metallic fub¬ ftances will not decompound an ammoniacal fait, unlefs they be affifted by a certain degree of heat. Now, as all thefe matters are extremely fixed, at lealt in comparifon with.a volatile alkali, they have the ad¬ vantage of being-able to refill the force of fire, and fo of ading in conjundjon therewith ; and fire greatly pro¬ motes the natural adion of fubftances upon one another whereas the volatile . alkali in the ammoniacal fait, being, unable to abide the force of fire, is compelled to defert its acid ; and that lb much the more quickly, as its affi¬ nity therewith is confiderably weakened hy the prefence of an earthy or metallic fubftance, both of which have a great affinity with acids. Thefe confiderations oblige us to conclude, that volatile alkalis have a fomewhat greater affinity, than abforbent earths and metallic fubftances, with acids. Ammoniacal falts projeded upon nitre in fufion make, it detonate ;. and the nitrous fal ammoniac detonates by, itfelf, without the addition of any inflammable matter. This lingular effed evidently demonftrates the exiftence, of an oily matter in volatile alkalis ; for it is certain that, nitre will never deflagrate without the concurrence and even the immediate contad of fome combuftible matter.. This oily fubftance is often found combined with vola¬ tile alkalis in fuch a large proportion as to difguife it in fome meafure, and render it exceeding foul. The fait, may be freed from its fuperfluous oil by repeated fublima- tions. j; .100 c H E M tions ; and particularly by fiibliming'it from abforbent earths, which readily drink up oils. This is called the reflificalion of a volatile alkali. The fait, which before was of a yellowifh or dirty Colour, by being thus recti¬ fied, becomes very white, and acquires an odour more ptingertt and lefs fetid than it had at firft, that is, when obtained by onefinglediftillation from a putrid fubftance. It is proper to obferve, that the rectification of a vo¬ latile alkali mud not be carried too far, or repeated too often ; for by that means it may be entirely decompofed at length; and particularly if an abforbent earth, and efpecially chalk, be employed for that purpofe, the fait may be converted into an oil, an earth, and water; Volatile alkalis aCt upon feveral metallic fubftances, and particularly on copper; of which they make a moft beautiful' blue folution; On this property depends a pretty fingular effeCI,- which happens fbmetimes when we Attempt by means of a volatile alkali to feparate copper from an acid with which it is combined. Inllead of fee¬ ing the liquor grow tuHaid, and the metal fall, both which generally happen when any alkali whatever is mix¬ ed with a: metallic folotion, we are furprifed to Obferve the folution of copper, upon adding a volatile alkali, re¬ tain its limpidity, and let fall no precipitate; or at leaf! if the liquor does grow turbid, it remains fo but for a moment, and inftantly recovers its tranfparency. This is occafioned bjr adding fuch a quantity of volatile alkali as is more than fufficient fully to faturate the acid of the folution, and conliderable enough to di/Tolve all the cop¬ per as faff as it is feparated from the acid. On this oc- cafion the liquor requires a deeper blue than it-had be¬ fore ; which arifes fr6m the property which volatile alkalis have df giving this metal, when combined with them, a fuller blue than any other folvent can: Hence we have a touchftone to difcbver copper where-ever it is; for, let the quantity of this metal, combined with other metals, be ever fo'fmall, a volatile alkali never fails to difcover it, by making it appear of a blue colour. Though a volatile a!kali be conftantly the refult of ’ pUtrefaCHorr, yet it mu ft not therefore be imagined, that none can be produced by Any other means; on the contrary, inoft of thofe which contain the ingredients neceflary to form it, yield no incohfiderable quantity thereof in di- ftillation. Tartar, for example, which by being burnt in an open fire is converted, as was fhewn, into a fixed alkali, yields a volatile alkali when it is decompofed in rlofe veffels; that is, when it is diftilled: Becaufe, in this latter cafe, the oily part is not dilfipated ot burnt, as it is by calcination in a naked fire, but has time to ti.iite with fome of the earth and acid of the mixt, in fueh a manner as to form a true volatile alkali. To prove that on this occafion, as well as on all o- thers, where unputrefied bodies yield a volatHe alkali, this fait is the product of the fire, we need only obierve, that in thefe diftillations it never rifes till after fome" part of the phlegm of the acid, and even of the thick oil of the mixt, is come over; which never is the cafe when it is formed before-hand in the body which is the fubjeft of the operation, as it is in thofe which have undergone pntrefaftrort: For this fait, being much lighter and more volatile than thofe other fubftances, rifes of courfe be¬ fore them in diftillatioh. A General Vtevj of Chemical Decompofition. Though we have confidered all the fubftances which enter into the compofition of vegetables, animals, and minerals, whether as primary or, as fecondary principles, it will not be improper to Ihew in what order we obtain thefe principles from the feveral mixts; and efpecially from vegetables and animals, becaufe they are much more complicated than minerals. This is called analy- Jing a compound. The method moft commonly taken to decompofe bo¬ dies is by applying to them fucceflive degrees of heat, from the gentleft to the moft violent, in appropriated veflelsr, fo contrived as to colled what exhales from them. By this means the principles are gradually feparated from each other; the moft volatile rife firft, and the reft fol¬ low in order, as they come to be aded on by the proper degree of heat: And this is called dijiillation. But it being obferved that fire, applied to the decom¬ pofition of bodies, moft commonly alters their fecondary principles very fenfibly, by combining them in a different manner with each other, or even partly decompofing them, and reducing them to their primitive principles,; other means have been ufed to feparate thofe principles without the help of fire. With this view the mixts to be decompofed are forci¬ bly comprefled, in order to fqueeze out of them all fuch parts of their fubftance as they will by this means part with ; or elfe thofe mixts are for a long time triturated, either along with water, which carries off all their fa- line and faponaceous contents ; or with folvents, fuch as ardent fpirits, capable of taking up every thing in them that'is of an oily or refinbus nature. We ftiall here give a fuccind account of the effeds of thefe different methods, as applied to the principal fub¬ ftances among vegetables-and animals, and likewife to fome minerals. Analysis ^Vegetable Substances. A vaft many vegetable fubftances, fuch as kernels and feeds, yield by ftrong compreffion great quantities of mild, fat, uhduous oik, which are not foluble in ardent fpirits : Thefe are what we called exprcJJ'ed oils. They are alfo fometimes called fat oils, on account of their unduoufnefs, in which they exceed all other forts of oil. As thefe oils are obtained without the aid of fire, it is certain that they exjfted in the mixt juft as we fee them, and that they are not in the leaft altered; which could not have been the cafe had they been obtained by diftillation : For that never produces any oils but fuch as are acrid and foluble in fpirit of wine. Some vegetable matters, fuch as the rind of citrons, lemons, Oranges, alfo yield, only by being fquee- zed between the fingers, a great deal of oil. Th’s fpirts out in fine fmall jets, which being received upon any po- liflied furface, fuch as a lobking-glafs, run together, and form a liquor that is a real oil. But CHEMISTRY. ioi But it muft be carefully noted, that this fort of oil, though obtained by expreffion only, is neverthelefs Very different from the oils mentioned before to which the ti¬ tle of exprtffed oils peculiarly belongs : For this is far lighter and thinner; moreover, it retains the perfect o- dour of the fruit which yields it, and is foluble in fpirit of wine; in a word, it is a true effential oil, but abounds fo in the fruits which produce it, and is lodged therein in fuch a manner, occupying a vaft number of little cells provided in the peel for its reception, that a very flight prefl'ure difeharges it; which is not the cafe with many vegetables that contain an eflential oil. Succulent and green plants yield by compreflion a great deal of liauor or juice, which conlifts of molt of the phlegm of the falts, and a fmall portion of the oil and earth of the plant. Thefe juices, being fet in a cool place for fome time, depofit faline cryflals, which are a combination of the acid of the plant with part of its oil and earth, wherein the acid is always predominant. Thefe falts, as is evident from the defeription here gi¬ ven, bear a great refemblance to the tartar of wine treat¬ ed of above. They aie called effential falts ; fo that tartar might likewife be called the effential fait of ouine. Dried plants, and fuch as are of a ligneous, or acid nature, require to be long triturated with water, before they will yield their eflential falts. Trituration with wa¬ ter is an excellent way to get out of them all their faline and faponaceous contents. A vegetable matter that is very oily yields its eflential fait with much difficulty, if at all; becaufe the excef- five quantity of oil entangles the fait fo that it cannot extricate itfelf or ffioot into cryftals. MrGerike, in his Princples of Ckemifhy, fays. That if part of the oil of a plant be extracted by fpirit of wine, its eflential fait may be afterwards obtained with more eafe and in greater quantity. Eflential falts are among thofe fubftances which can¬ not be extracted from mixts by diftillation; for the firfl impreflion of fire decompofes them. Though the acid which predominates in the eflential falls of plants be moll commonly analogous to the vege¬ table acid, properly fo called, that is, to the acid of vinegar and tartar, which is probably no other than the vitriolic acid difguifed; yet it fometimes-differs there¬ from, and fomewhat refembles the nitrous or the marine acid. This depends on the places where the plants grow which produce thefe falts : If they be fubmarine plants, their acid is a-kin to the acid of fea-falt; if, on the con¬ trary, they grow upon walls, or in nitrous grounds, their acid is like that of nitre. Sometimes one and the fame plant contains falts analogous to all the three mineral a- cids; which (hews that the vegetable acids are no other than the mineral acids varioufly changed by circulatingy through plants. Liquors containing the eflential falts of plants being e- vaporated by a gentle heat to the confiftence of honey, or even further, are called extrafts. Hence it is plain, that an extraft is nothing but the effential fait of a plant, combined with fome particles of its oil and earth, that re- Vol. II. No. 34. 3 mained fufpended in the liquor, and are now incorpora¬ ted by evaporation. Extratfs of plants are alfo prepared by boiling them long in water, and then evaporating fome part of it. But thefe extracts are of inferior virtue; becaufe the fire dif- fipates many of the oily and faline parts. Emulsions. Subftances which abound much in oil, being bruifed and triturated with water for fome time, afford a liquor of an opaque dead-white colour like milk. This liquor confifls of fuch juices as the water is capable of diffol- ving, together with a portion of the oil, which being na¬ turally indiflbluble in water, i5 only divided and difper- fed in the liquor, the limpidity whereof is by that means deftroyed. This fort of oily liquor, in which the oil is only divided, not dtflblved, is called an emulfion. Tire oily particles in emulfions fpontaneoufly feparate from the water, when left at refl, and, uniting into geater maffes, rife, on account of their lightnefs, to the furface of the liquor, which by that means recovers a degree of tranf- parency. If vegetables, abounding in effential oils and refins, be digefted in fpirit of wine, the menftruum takes up thefe oily matters, as being capable of diffolving them; and they may afterwards be eafily feparated from it by the affulion of water. The water, with which fpirit of wine has a greater affinity than with oily matters, feparates them by this means from their folvent, agreeable to the common laws of affinities. Without the help of fire fcarce any thing, befides the fubltances already mentioned, can be obtained from a plant: But by the means of diflillation we are enabled to analyfe them more completely. ' In profecuting this me¬ thod of extradling from a plant the feveral principles oF which it confifls, the following order is to be obferved. A plant being expofed to a very gentle heat, in a di- ftilling veffel fet in the balneum maria, yields a water which retains the perfedt fmell thereof. Some chemifls, and. particularly the illuftrious Boerhaave, have called this liquor xht fpirit ns rettor. The nature of this odo¬ riferous part of plants is not yet thoroughly known ; be¬ caufe it is fo very volatile, that it is difficult to fubjedt it to the experiments neceffary for difeovering all its pro¬ perties. If inftdad of diftilling the plant in the balneum maria, it be diftilled oyer a naked fire, with the precaution of putting a certain quantity of water into the diflilling vef¬ fel along with it, to prevent its fuffering a greater heat than that of boiling water, all the eflential oil contained in that plant will rife together with that water, and with the fame degree of heat. On this occafion it muft be obferved, that no eflential oil can be obtained from a plant after the fpirttus reftor hath been drawn off; which gives ground to think that the volatility of thefe oils is o ving to that Ipirit. The heat of boiling water is alio fufficient to feparate from vegetable matters the fat oils which they contain : That, however, is to be done by the way of decodtion 2 C only, \ \ W'j ^003 S' 102 C H E M only, and not by diftillation ; bccaufe, though theft; oils will fwim on water,’yet they will not rife in vapours without a greater degree of heat. When the eflential oil is come over, if the plant be expofed to a naked fire, without the addition of water, and the heat be increafed a little, a phlegm will rife that gradually grows acid ; after which, if the heat be increa¬ fed as occafion requires, there will come over a thicker and heavier oil ; from fome a volatile alkali; aqd laft of all, a very thick, black, empyreumatic oil. When nothing more rifes with the 11 rongelt degree of heat, there remains of the plant a mere coal only, called the caput mortuum, or terra damnata. This coal when burnt falls into allies, v/hich being lixiviated with wa¬ ter give a fixed'alkali. It is obfervable, that in the dillillation of plants which yield an acid and a volatile alkali, thefe two falts are of¬ ten found quitediftinft and feparate in the fame receiver; which feems very extraordinary, confidering that they are naturally difpofed to unite, and have a great affinity with one another. The reafon of this phenomenon is, that they are both combined with much oil, which em- barrafies them fo that they cannot unite to form a neu¬ tral fait, as they would not fail to do were it not for that impediment. All vegetables, except fuch as yield a great deal of volatile alkali, being burnt in an open fire, and fo as to flame, leave in their allies a large quantity of, an acrid, cauftic, fixed alkali. But if care be taken to fmother them, fo as to prevent their flaming while they burn, by covering them with fomething that may continually beat down again what exhales, the fait obtained from their alhes will be much lefs acrid and cauftic ; the caufe whereof is, that fome part of the acid and oil of the plant being detained in the burning, and flopped from being difiipated by the fire, Combines with its alkali. Thefe falts cryftallize, and being much milder than the common fixed. alkalis, may be tifed in medicine, and ta¬ ken internally. They are called Tachetiius's falls, be- caofe invented by that chemift. Marine plants yield a fixed alkali analogous to that of fea-falt. As for all other plants or vegetable fubftan- . ces, the .fixed alkalis obtained from them, if rightly pre¬ pared and thoroughly calcined, are all perfeftly alike, and of the fame nature. The laft obfervation we have to make on the pro- duftion of a fixed alkali is, that if the plant you intend to work upon be fteeped or boiled in water before you burn it, a much fmafler quantity of fait will be obtained from it ; nay, it will yield none at all, if repeated boilings have robbed it entirely of thofe faline particles which muft neceflarily concur with its earth to form a fixed alkali. The Analysis of Animal Substances. Succulent animal fubftances, fuch as new-killed fl'efh, yield by expreflion a juice or liquid, which is no other than the phlegm, replete with all the principles of the animal body, except the earth, of which it contains but little. The hard or dry parts, fuch as the horns, bones, tec. yield a fimilar juice, by boiling them in wa¬ ter. Thefe juices become thick, like a glue or jelly, I S T R Y. when their watery parts are evaporated ; and in this ftate they are true extrafts of animal matters. Thefe juices afford no cryftals of effential fait, like thofe ob¬ tained, from vegetables, and fhew no fign either of an a- cid or an alkali. Great part of the oil which is in the fldh of animals may be eafily feparated without the help of fire; for it lies in a manner by itfelf: It is commonly in a concrete form, and is called fat. This, oil fomewhat refembles the fat oils of vegetables; for like them it is mild, unc¬ tuous, indiffoluble in fpirit of wine, and is fubtilized and attenuated by the aftion of fire. But there is not in animals, as in vegetables, any light effential oil, which rifes with the heat of boiling water ; fo that, properly fpeaking, animals contain but one fort of oil. Few animal fubftances yield a perceptible acid. Ants and bees are almoft the only ones from which any can be obtained ; and indeed the quantity which they yield is very fmall, as the acid itfelf is extremely weak. The reafon thereof is, that as animals do not draw their nourifhment immediately from the earth, but feed wholly either on vegetables or on the flefti of other ani¬ mals, the mineral acids, which have already undergone a great change by the union contrafted between them and the oily matters of the vegetable kingdom, enter into a clofer union and combination with thele oily parts while they are palling through the organs and ftrainers of ani¬ mals ; Whereby their properties are deftroyed, or at leaft fo impaired that they are no longer fenfible. Animal matters yield in diftillation, firft, a phlegm, and then, on increafing the fire, a pretty clear oil, which gradually becomes thicker, blacker, more fetid, and em¬ pyreumatic. It is accompanied with a great deal of vo¬ latile alkali; and if the fire be taifed and kept up till no¬ thing more comes over, there will remain in the diftilling veffel a coal like that of vegetables; except that when it is reduced to allies, no fixed alkali, or at leaft very little, can be obtained from them, as from the allies of vegetables. This arifes from hence, that, as we faid before, the faline principle in animals being more inti¬ mately united with the oil than it is in plants, and being confequently more attenuated and fubtilized, is.too. vola¬ tile to enter into the combination of a fixed alkali; on the contrary, it is more difpofed to join in forming a vo¬ latile alkali, which on this occalion does not rife till after the oil, and therefore muft certainly be the produc¬ tion of the fire. The chyle, 'and the milk of animals which feed on plants, ftill retain fome likenefs to vegetables ; becaufe the principles of which thefe liquors are compofed have not gone through all the changes which they muft fuffer before they enter into the animal combination. Urine'and fweat are excrementitious aqueous'liquors, loaded chiefly with the faline particles which are of no fervice towards the nouriftiment of the animal, but pafs through its ftrainers without receiving any alteration ; fuch as the neutral falts which have a fixed alkali for their balls, and particularly the fea-falt which happens to be in the food of animals, whether- it exift therein natu¬ rally, as it does in fome plants, or whether the animals eat it to pleafe their palates. C H E M The faliva, the pancreatic juice, and efpecially the bile, are faponaceous liquors ; that is, they cpnfift of faline and oily particles combined together ; fo that being them- felves dilfolved in- an aqueous liquor, they are capable of dilfolving likewife the oily parts, and of tendering them mifcible with water. Laftly, jThe blood being; the receptacle of all thefe liquors, partakes of the nature of each, more or lefs in proportion to the quantity thereof which it contains. The Analysis of Mineral Substances. Minerals differ greatly from vegetables, and from animals; they are not near fo complex as thofe organized bodies, and their principles are much more fimple ; whence it follows, that thefe principles are much more clofely conne&ed, and that they cannot be feparated without the help of fire ; which not having on their parts the fame adtion and the fame power as 'on organized bo¬ dies, hath not the fame ill effedt on them ; we mean the effedf of changing their principles, or even deftroying them entirely. We do not here fpeak of pure, vitrifabje, or refrac¬ tory earths of mere metals and femi-metals; of pure acids ; or even of their fimpleit combinations, fuch as fulphur, vitriol, alum, fea fair: - Of all thefe we have faid enough. We are now to treat of bodies that are more complex, and therefore more fufceptible of decompofition. Thefe bodies are compound maffes or combinations of thofe above-mentioned ; that is, metallic fubltances as they are found in the bowels of the earth, united with feveral forts of fand, ftones, earths, femi-metals, fulphur, <&a When the metallic matter is combine'd^vith other mat¬ ters in fuch a proportion to the reft that it may be fepa¬ rated from them with advantage and profit, thefe com¬ pounds are called ores when the .cafe is otherwife, ,they are called pyrites, and marcajites ; efpecially if fulphur or arfenic be predominant therein, which often happens. In order to analyfe an ore, and get out of it the metal it contains, the firft ftep is to free it from a great deal of earth and ftones which commonly adhere to-it very (light¬ ly and fuperficially. This is effe&ed by pounding the ore, and then wafning it in water ; to the bbttom of which the metalline parts prefentlylink, as being the hea- vieft, while the fmall particles of earth and ftone remain fufpctjded fome time longer. Thus the metallic part is left combined with fuch mat¬ ters only as are moft intimately complicated with it. Thefe fubftances are moft commonly fulphur arid arfenic. Now, as they are much more volatile than other mineral matters, they may be diffipated in vapours, or the ful¬ phur may be confumed, by expofmg the ore which con¬ tains them to a proper degree of- heat. If the fulphur and arfenic be defined by themfelves, the fumes thereof may be catched andeolledted in proper velfels and places. This operation is called roafling in ore. The metal thus depurated is now fit to be expofed. to a greater force of fire, capable of melting it. On this occafion the femi metals and the imperfeft me¬ tals require the addition of fome matter abounding in fhlogifton, particularly charcoal-duft ; becaufe thefe me- I R Y. 103 tallic fubftances Jofe their phlogifton by the a under the marine acid. The eighth column fpecifies the affinities of metallic" fubftances with acids. The affinities of the acids, which with refpeft to fixed alkalis, volatile alkalis, and abfor¬ bent earths, fucceed each other uniformly,. do not ap¬ pear in the fame order here. The marine acid, inftead of being placed below the vitriolic and nitrous acids,, ftands, on the contrary, at their head ; becaufe, in faff,, this acid feparates metalline fubftances ffom all the other acids with which thev happen to be united,, and, forcing thefe acids to quit poffeffion, intrudes into their place. Neverthelefs-. this is not a general rule ; for feveral me¬ talline fubftances muft be excepted; particularly iron and copper. The ninth" column declares the affinities of fulphur. Fixed alkalis, iron, copper lead, filver, regulus of an- timonv, mercury, and gold, ftand below it in the order- of their affinities. With regard ro gold, it muft be ob- ferved, that it will not unite with pure fulphur ; it fuf- fers: soft C H E M fere itfelf to be diffolved only by the liver of fulphur, which is known to be a compoiition of fulphur and fixed alkali. At the head of the tenth column appears mercury, and beneath it feveral metalline fubftances, in the order of their affinities with it. Thofe metalline fubitances are gold, filver, lead, copper, zinc, and regulus of anti¬ mony. The eleventh column ffiews that lead has a greater affi¬ nity with filver than with copper. The twelfth, that copper has a greater affinity with mercury than with calamine. The thirteenth, that filver has a greater affinity with lead than with copper. The fourteenth contains the affinities of iron. Re¬ gulus of antimony Hands immediately underneath it, as being the metallic fubllance which has the greateft affi¬ nity with it. Silver, copper, and lead, are placed to¬ gether in the next fquare below, becaufe the degrees of affinitj'. which thofe metals have with iron are not exactly determined. The fame is to be faid of the fifteenth column : Re¬ gulus of antimony Hands at its head *, iron is immediately below it; and below the iron the fame three metals oc¬ cupy one fquare as before. LaHly, The fixteenth column indicates that water has a greater affinity with fpirit of wine than with falls. By this general expreffion muH not be underHood any faline fubfance whatever; but only the neutral falts, which fpirif of wine frees from the water that kept them in fo- lution. Fixed alkalis, on the contrary, as well as the mineral acids, have a greater affinity than fpirit of wine with water ; fo that thefe faline fubflances, being well dephlegmatcd and mixed with fpirit of wine, imbibe the water it contains and re&ify it. The ’Theory of Conftrutting the Vejfels mofl commonly ufed in Chemijlry. Chemists cannot perform the operations of their art without the help of a confiderable number of veflels, in- Hruments, and furnaces, adapted to. contain the bodies on which they intend to work, and to apply to them the feveral degrees of heat required by different proceffes. Veffels intended for chemical operations ffiould be able to bear, without breaking, the fudden application of great heat and great cold ; be impenetrable to every thing, and unalterable by any folvent; unvitrifiable, and capable of enduring the moH violent fire without melt¬ ing : But hitherto no veffels have been found with all thefe qualities united. They are made of fundry materials, namely, of me¬ tal, of glafs, and of earth. Metalline veffels, efpecially thofe made of iron or copper, are apt to be corroded by ahnolt every faline, oily, or even aqueous fubHance. For this reafon, in order to render the ufe of them a lit¬ tle more^extenfive, they are tinned on the infide. But, notwithffanding this precaution, they are on many occa- frons not to be trufled ; and ffiould never be employed in any nice operations which require great accuracy ; they are, moreover, incapable of refiffing the force of fire. I S T R Y. Earthen veffels are ol£ feveral forts. Some, that are made of a refraftory earth, are capable of .being fudden- ly expofed to a ffrong fire without breaking, and even of fuffaining a great degree of heat for a confiderable time: But they generally fuffer the vapours of the matters which they contain, as well as vitrified metals, to pafs through them ; efpecially the glafs of lead, which eafily pene¬ trates them, and runs through their pores, as through a a fieve. There are others made of an earth, that, when well baked, looks as if it were half vitrified : Thefe be¬ ing much lefs porous are capable of retaining the vapours of the matters which they contain, and even glafs of lead in fufion; which is one of the feverefl trials a veffel can be put to: But then they are moit brittle than the other fort. Good glafs-veffels ffiould conffantly be employed in preference to all others, whenever they can poffibly be ufed : And that not only becaufe they are no way inju¬ red by the moH adfive folvents, nor fuffer any part of what they contain to pafs through, but alfo becaufe their tranfparency allows the chemiff to obferve what paffes within them' which is always both curious and ufeful. But it is pity, that veffels of this fort ffiould not be a- bie to endure a fierce fire'without melting. Diffiilation, as hath been already faid, is an opera¬ tion by which we feparate from a body, by the help of a gradual heat, the feveral principles of which it con fills. There are three methods of diffilling. The firff is performed by applying the heat over the body whofe principles are to be extracted. In this cafe, as the li¬ quors when heated and converted into vapours conffantly endeavour to fly from the centre of heat, they are for¬ ced to re-unite in the lower part of the veffel that con¬ tains the matter in diffillation, and fo pafling through the pores or holes of that veffel, they fall into another cold veffel applied underneath to receive them. This way of diffilling is, on this account, called diftilling per defcenfum. It requires no other apparatus than two veffels figured like fegments of hollow fpheres, whereof that which is pierced with little holes, and intended to contain the matter to be diftilled, ought to be much lefs than the other which is to contain the fire, and dole its aperture exaftly; the whole together being fupported vertically upon a third veffel, which is to ferve the purpole of a recipient, admitting into its mouth the convex bot¬ tom of the veffel containing the matter to be diffilled, which muff accurately fill it. This method of diffilling is but little ufed. The fecond method of diftilling is performed by ap¬ plying the heat underneath the matter to be decompofed. On this occafion the liquors being heated, rarefied, and converted into vapours, rife, and are condenfed in a vef¬ fel contrived for that phrpofe, which we ffiall prefently defcribe. This way of diftilling is called diftilling per afcenfum, and is much ufed. The veffel in which the diffillation per afcenfum is performed, we call an alembic. Plate LXIV. fig.J. There are feveral forts thereof differing from one an¬ other both in the matter of which, and tfie manner in Which, they are made. Thofe C H E M Thofe employed to draw the odoriferous waters and effential oils of plants are generally made of copper, and confift of feveral pieces. The firft, which is defigned to contain the plant, is formed nearly like a hollow cone,- the vertex whereof is drawn out in the fhape of a hollow cylinder or tube : This part is named the cuburbit, Plate LXIV. fig. i. A ; and its tube the neck of the alembic B. To the upper end of this tube another veffel is foldered : This is called the head C, and commonly has likewife the form of a cone, joined to the neck of the alembic by its'bafe, round which on the infide is hollowed a fmall groove communicating with an orifice that opens at its moft depending part. To this orifice is foldered a fmall pipe in a diredtion Hoping downwards, which is called the nofe, fpout, or beak D of the alembic. ' As foon as the matters contained in the alembic grow hot,' vapours begin to arife from them, and afcending through the neck of the alembic into the head, are by the fides thereof Hopped and condenfed: From thence they trickle down in little ftreams to the groove, which conveys them to the fpout; and by that they pafs out of the alembic into a glafs veffel or receiver G with a long neck, the end of the fpout being introduced into that neck and luted thereto. To facilitate the refrigeration and condenfation of the vapours circulating in the head, all alembics of metal are ‘moreover provided with another piece, which is a kind of large pan of the Qime metal, fitted and foldered round the head. This piece ferves to keep cold water in, which inceffantly cools the head, and therefore it is call¬ ed the refrigeratory E. The water in the refrigeratory itfelf grows hot after fome time, and muft therefore be changed occafionally ; the heated water being firft drawn off by means of a cock fixed near the bottom of the re¬ frigeratory. All copper alembics Ihould be tinned on the infide for the reafons already given. When faline fpirits are to be diftilled, alembics of me¬ tal muft not be fifed; becaufe the faline vapours would corrode them. In this cafe recourfe muft be had to a- lembics of glafs. Thefe confift of pieces only; namely, a cucurbit, whofe fuperior orifice is admitted into, and ex- a There are fome alembics of glafs, blown in fuch a man¬ ner by the workmen, that the body and head form but one continued piece. As thefe alembics do not ftand in need of having their feveral pieces luted together, they are very ufeful on fome occafions, when fuch exceeding fubtile vapours rife as are capable of tranfpiring through lutes. The head muft be open at the top, and provided with a fliort tube, through which by means of a funnel with a long pipe, the matter to be diftilled may be in¬ troduced into the cucurbit. This is to be exaiftly clofed with a.glafs ftopple, the furface whereof muft be made to fit the infide of the tube in every point, by rubbing thole two pieces well together with emery. Another fort of alembic hath alfo been invented, which may be ufed with advantage when cohobation is required; that is, when the liquor obtained by diftilla- tion is to be returned upon the matter in the cucurbit; and efpecially when it is intended that this cohobation lhall be repeated a great number of times. The veffel we are fpeaking of is conftrufted exaftly in the fame manner as that laft defcribed ; except that its beak, in- ftead of being in a ftreight line as in the other alembics, forms a circular arch, and re-enters the cavity of the cu¬ curbit, in order to convey back again the liquor colleft- ed in the head. This inftrument hath commonly two beaks oppofite to each other, both turned in this manner, and is called a pelican : It faves the artift the trouble of frequently unluting and reluting his veffels, as well as the lofs of a great many vapours. There are certain fubftances which in diftillation af¬ ford matters in a concrete form, or rife wholly in the form of a very light powder, called flowers. When fuch fubftances are to be diftilled, the cucurbit which contains them is covered with a head without a nofe, which,is named a blind head. When the flowers rife in great quantities and very high, a number of beads is employed to colleft them ; or rather a number of a kind of pots, confifting of a bo¬ dy only without any bottom, which fitting one into the other form a canal, that may be lengthened or Ihortened at pleafure, according as the flowers to be fublimed are more or lefs volatile. The laft of the heads, which ter¬ minates the canal, is quite clofe at one end, and makes a true blind-head. Thefe veffels are called 'aludels : they are ufually of earthen or ftone ware. All the veffels above mentioned are fit only for di¬ ftilling fuch light volatile matters as can be eafily raifed and brought over; fuch as phlegm, effential oils, fra¬ grant waters, acid oily fpirits, volatile alkalis, &c. But when the point is to procure,- by diftillation, principles that are much lefs volatile, and incapable of rifing high, fuch as the thick fetid oils, the vitriolic, the nitrous, and the marine acids, we are under a neceffity of having recourfe to other veffels, and another manner of di¬ ftilling. It is eafy to imagine, that fuch a veffel muft be much lower than the alembic. It is indeed no more than a hollow globe, whofe upper part degenerates into* a neck 2 E or no C H E M or tube, that is bent into a horizontal poiitioh; for which , reafon this inflrument is called a retort: It is always of one Angle piece. The matter to be diftilled is introduced into the body of the retort by means of a ladle with a long tubular fliank. Then it is fet in a furnace built purpofely for this ufe, and fo that the neck of the retort coming out of the furnace may, like the the nofe of the alembic, Hand in a floping pofition, to facilitate the egrefs of the liquors, which by its means are conveyed to a re¬ ceiver, into which it is introduced, and with which it is luted. This way of diftilling, in which the vapours feem rather to be driven out of the veffel horizontally .and laterally, than railed up and fublimed, is for that reafon called diftillation per- latus* Retorts are, of all the inftruments of diftillation, thofe that muft fuftain the greateft heat, and refift the ftrongeft folvents ; and therefore they mull not be made of metal. Some, however, which are made of iron may do well enough on certain occafions : The reft are either of glafs or earth. Thofe of glafs, for the reafons above given, are preferable to the other fort, in all cafes where they are not to be expofed to fuch a force of fire as may melt them. The beft glafs, that which ftands both heat and folvents beft, is that in which there are feweft alka¬ line falts : Of this fort is the green German glafs : The beautiful white cryftaf glafs is far from being equally fer- viceable. Retorts, as well as alembics, may be of different forms. For example, fome matters are apt to fwell and rife over the neck of the retort in fubftance without fuf- fering any decompofition ; when fuch matters are to be diftilled in a retort, it is proper that the body of the vef¬ fel, inftead of being globular, be drawn out into the form of a pear, fo as nearly to refemble that of a cucurbit. In a retort of this kind, the diftance between the bottom and the neck being much greater than in thofe whofe bodies are fpherical, the matters contained have much more room for expanfion ; fo that the inconvenience here mentioned is thereby prevented. Retorts of this form are called Englifh retorts : as they hold the mid¬ dle place between alembics and common retorts, they may be ufed to diftill fuch matters as have a mean degree of volatility between the greateft and the leaft. It is moreover proper to have in a laboratory fundry fetorts with necks of different diameters. Wide necks will be found the fitteft for conveying thick matters, and fuch as readily become fixed; for inftance, fome very thick fetid oils, butter of antimony, isc. for as thefe matters acquire a confiftence as foon as they are out of the reach of a certain degree of heat, they would foon choak up a narrow neck, and by flopping the vapours, which rife at the fame time from the retort, might occa- fion the burfting of the veffels. Some retorts are alfo made with an opening on their upper fide, like that of tubulated glafs alembics, which is to be clofed in the fame manner with a glafs ftopple. Thefe retorts are alfo called tubulated retorts, and ought alway> to be ufed whenever it is neceffary to introduce frelh matter into the retort during the operation ; feeing it may be done by means of this invention, v/ithout un- : S T R Y. luting and-reluting the veffels ; which ought always to be avoided as much as poflible. One of the things that moft perplexes the chemifts is, the prodigious elafticity of many different vapours, which are frequently difeharged with impetuofity during the di¬ ftillation, and are even capable of burfting the veffels with explofion, and with danger to the artift. On fuch occafions it is abfolutely neceffary to give thefe vapours vent, as we Ihall direft in its proper place : But as that can never be done without lofing a great many of them ; as fome of them in particular are fo elaftic, that fcarce any at all would remain in the veffel ; for inftance, thofe of the fpirit of nitre, and efpecially thofe of the fmoking fpirit of fait; the practice is to make ufe of very large receivers, of about eighteen or twenty inches diameter, that the vapours may have fufficient room to circulate in, and, by applying to the wide furface prefented them by the extenfive infide of fuch a large veffel, may be con- denfed into drops. Thefe huge receivers are commonly in the form of hollow globes, and are called ballons. To give thefe vapours ftill more room, ballons have been contrived with two open gullets in each, diametri¬ cally oppofite to one another; whereof one admits the neck of the retort, and the other is received by one of the gullets of a fecond ballon of the fame form, which is joined in like manner to a third, and fo on. By this ar¬ tifice the fpace may be enlarged at pleafure. Thefe bal¬ lons with two neck's are called adopters. ' Operations on bodies that are abfolutely fixed, as me¬ tals, ftones, fand, &c. require only fuch veffels as are capable of containing thofe bodies and fefifting the force of fire. Thefe veffels are little hollow pots, of diffe¬ rent dimenfions, which are called crucibles. Crucibles can hardly be made of any thing but earth ; they ought to have a cover of the fame material fitted to Ihut them clofe. The beft earth we know is that whereof thofe pots are made'in which butter is brought from Bretagne: Thefe pots themfelves are exceeding good crucibles; and they are almoft the only ones that are capable of holding glafs of lead in fufion, without being penetrated by it. For the roafting of ores, that is, freeing them by the help of fire from their fulphureous and arfenical parts, little cups made of the fame, material with cruci¬ bles are ufed ; but they are made flat, ftiallow, and wi¬ der above than below, that thefe volatile matters may the more freely exhale. Thefe veffels are called tejis, or fcorifiers: They are fcarce ufed but in the docimaftic art, that is, in making fmall affays of ores. The TheQry of con ft rutting the Furnaces moft commonly ufed in Chemiftry. Skill in coridufting and applying fire properly, and determining its different idegrees, is of very great confe- quence to the fuccefs of chemical operations. As it is exceeding difficult to govern and moderate the adfion of fire, when the veffels in which any operation is performed are immediately expofed to it, chemifts have contrived to convey heat to their veffels, in nice opera¬ tions, through different mediums, which they place oc- cafionly between thofe veffels and the fire. Thofe C H E M Thofe intermediate fubfta^ces in which they plunge their veflels are called baths. They are either fluid or folid : The fluid baths are water, or its vapours. When the diftilling veflel is fet in water, the bath is called balneum marise, or. the water-bath; and the greateft de¬ gree of heat of which it is fufceptible is that of boiling wa¬ ter. When the veflel is expofed only to the vapours which exhale from water, this forms the vapour-bath: the heat of which is nearly the fame with that of the balne¬ um maria. Thefe baths are ufeful for diftilling eflential oils, ardent fpirits, fweet-fcented'waters; in a word, all fuch fubftances as cannot bear a greater heat without prejudice either to their odour, or to fome of their o- ther qualities. Baths may alfo be made of any other fluids, fuch as oils, mercury, fcc. which are capable of receiving and communicating much more heat ; but they are very fel- dom ufed. When a more confiderable degree of heat is required, a bath is prepared of any folid matter reduced to a fine powder, fuch as fand, allies, filings of iron, i6v.- The heat of thefe baths may be pulhed fo far as to make the-bottom of the veflel become faintly red. By plun¬ ging a thermometer into the bath, by the fide of the vef- fel, it is eafy to obferve the precife degree of heat ap¬ plied to the fubftance on which you are working. It is neceflary that the thermometers employed on this occa- fion be'conftrufted on good principles, and fo contrived as to be eafily compared with thofe of the moft celebrated natural phiiofojihers. Thofe of the illuftrious Reaumur are moft ufed and beft known, fo that it would not be amifs to give them the preference. When a greater heat is required than any of thofe baths-can give, the veflels muft be fet immediately- on live-coals, or in a flaming fire : this is called working with a naked fire ; and in this cafe it is much more difficult than in the other to determine the degrees of heat. There are feveral ways of applying a naked fire. When the heat or flame is refledied upon the upper part of the veflel which is expofed to the fire, this is called a rever¬ berated-heat. A melting heat is that which is ftrong e- nough to fufe moft bodies. A forging heat is that of a fire which is forcibly excited by the conftant blaft of a pair of bellows, or more. There is alfo another fort of fire which ferves very commodioufly for many operations, becaufe it does not require to be fed or frequently mended : This is afford¬ ed by a lamp with one or more wicks, and may be called a lamp-heat. It is fcarce ever employed but to heat baths, in operations which require a gentle and long con¬ tinued warmth : if it hath any fault, it is that of growing gradually hotter. All thefe different ways of applying fire require fur¬ naces of different conftrudions : We (hall therefore de- fcribe fuch as are of principal and moft neceflary ufe. ' Furnaces muft be divided into different parts or ftories, each of which has its particular ufe and name. The lower part of the furnace defigned for receiving the alhes, and giving paffage to the air, is called the alh- hole. The alh-hole is terminated above by a grate, the ufe of which is to fupport the coals and wood, which are to be burnt thereon : This part is called the fire-place. I S T R Y. Ill The fire-place is in like manner terminated above by fe¬ veral iron bars, which lie quite a-cro^s it from right to left, in lines parallel to each other : The ufe of thefe bars is to fuftain the veffels in which the operations are to be performed. The fpace above thefe bars to the top of the furnace is the upper ftory, and may be called the laboratory of the furnace. Laftly, fome furnace are quite covered above, by means of a kind of vaulted roof called the dome. Furnaces have moreover feveral apertures: one of thefe is at the ^fh-hole, which gives paflage to the air, and through y/hich the afhes that fall through the grate are raked out; this aperture iS called the afti-hole door : an¬ other is at the fire-place, through which the fire is fup- plied with fuel, as occafion requires ; this is called the mouth or door of the fire-place, or the ftoke-hole : there is a third in the upper ftory, through which the neck of the veflel paffes ; and a fourth in the dome, for carrying off the fuliginofities of combuftible matters, which is call¬ ed the Chimney. To conclude, there are feveral other openings in the feveral parts of the furnace, {he ufe whereof is to admit the air into thofe places, and alfo, as they can be eafily Ihut, to incite or flacken the adivity of the fire, and fo to regulate it; which has procured them the title of re- g'Jiers. All the other openings of the furnace fhould be made to Ihut very clqfe, the better to aflift in governing the fire ; by which means they likewife do the office of regifters. In order to our forming a juft and general idea of the conftrudtion of furnaces, and of the difpofition of the fe¬ veral apertures in them, with a view to increafe ordimi- nilh the a&ivity of the fire, it will be proper to lay down, as our ground-work, certain principles of natural philo- fophy, the truth of which is demonllrated by experience. And firft, every bodyjcnows that combuftible matters will not burn or confume unlefs they have a free commu¬ nication with the air ; infomuch that if they be deprived thereof, even when burning moft rapidly, they will be extinguiftied at once : that confequently combuftion is greatly promoted by the frequent acceflion of frefti air; and that a ftream of air, directed fo as to pafs with im- petuolity through burning fuel, excites the fire to the greateft poflible adlivity. Secondly, It is certain that the air which touches or comes near ignited bodies is heated, rarefied, and ren¬ dered lighter than the air about.it; that is; further di- ftant from the centre of heat ; and confeque'ntly that this air fo heated and become lighter is neceffarily determined' thereby to afcend and mount aloft, in order to make room for that which is lefs heated and not fo light,.' which by its weight and elafticity tends to occupy the place quitted by the other. Another confequence hereof is^ that if fire be kindled in a place inclofed every where but above and below, a current of air will be formed in that place, running in a diredion from the bottom to the top ; fo that if any light bodies be applied to the open¬ ing below, .they will be carried up towards the fire ; but, on the contrary, if they be held at the opening above, they will be impelled by a force which will drive them up and carry them awaj from the fire. Thirdly, 112 C H E M Thirdly, and laftly, it is a truth demonftrated in hy¬ draulics, that the velocity of a given quantity of any fluid, determined to flow in any direction whatever, is fo much the- greater, the narrower the channel is to which that fluid is confined ; and confequently that the velocity of a fluid will be increafed by making it run from a wider through a narrower pafiage. Thefe principles being eftablifhed, it is eafy to apply them to the conftruftion of furnaces. Firft, if a fire be kindled in the fire-place of a furnace, which is open on all fides, it burns nearly as if it were in the open air. It has with the furrounding air a free communication ; fo that frelh air is continually admitted to facilitate the en¬ tire combuftion of the inflammable matters employed as fuel. But there being nothing to determine that air to pafs with rapidity through the fire in this cafe, it does not at all augment the atfivity thereof, but fuffers it to wade away quietly. Secondly, If the afli-hole or dome of a furnace in which a fire is burning be flmt quite clofe, then there is no longer any free communication between the air and the fire : if the afli-hole be fhut. the air is debarred from having free accefs to the fire ; if the dome'be ftopt, the egrefs of the air rarefied by the fire is prevented ; and confequently the fire muft in either cafe burn very faintly and flowly, gradually die away, and at laft go quite out. Thirdly, If all the openings of the furnace be wholly doled, it is evident that the fire will be very quickly ex- tinguiflied. Fourthly, If only the lateral openings of the fire-place be (hut, leaving the afli-hole and upper part of the fur¬ nace open ; it is plain that the air entering by the afli- hole will neceflarily be determined to go out at top, and that confequently a current of air will be formed, which will pafs through the fire, and make it burn brilkly and vigoroufly. Fifthly, If both the afli-hole and the upper flory of the furnace be of fome lengthy and form canals either cylin- diic or prifmatic, then the air being kept in the fame di- redtion through a longer fpace, the courfe of its dream •will be both dronger and better determined, and confe¬ quently the fire will be more animated by it. Sixthly, and ladly, if the afli hole and the upper part of the furnace, indead of being cylindric or prifmatic canak, have the form of truncated cones or pyramids, danding on their bafes, and fo ordered that the upper opening of the afli-hole adjoining to the fire-place may be wider than the bafe of the fuperior cone or pyramid; then the dream of air, being forced to pafs inceflantly from a larger channel through a fmaller, mud be con- fiderably accelerated, and procure to the fire the great- ed aftivity which it can receive from the make of a fur nace. The materials fitted for building furnaces are, i. Bricks, joined together with potters clay mixed with fand, and moidened with water. 2.. Potters clay mingled with potfherds, moidened with water, and baked in a vi¬ olent fire. 3. Iron; of which all furnaces may be made; wi,th*this precaution, that the infide be provided with a great many prominent points, as fadenings for a :coat of earth, with which the internal parts of the furnace I S T . R Y. mud neceflarily be covered to defend it from the aftion of the fire. The reverberating furnace is one of thofe that are mod employed in chemidry : it is proper for didillations by the retort, arid fliould be condrudted in the following manner. Fird, The ufe of the afli-hole being, as was faid, to give paflage to the air, and to receive the allies, no bad confequence can attend its being made pretty high : It may have from twelve to twenty or twenty-four inches in heighth. Its aperture ftiould be wide enough to admit billets of wood when a great fire is to be made. Secondly, The afli-hole mud be terminated at its up¬ per part by an- iron grate, the bars of which fliould be very fubdantial, that they may refid the adtion of the fire : this grate is the bottom of the fire-place, and de- dined to fupport the coals. In the lateral part of the fire-place, and nearly about the fame height with the grate, there fliould be a hole of fuch a fize that it may eafily admit charcoal, as well as little tongs and (hovels fyr managing the fire. This aperture or mouth of the fire-place ftiould be perpendicularly over the mouth of the afli-hole. Thirdly, from fix to eight or ten inches high above the grate, over the afli-hole, little apertures mud be made in the walls of the furnace, of eight or ten lines in diameter, an inch from one another, and thofe in one fide mud be diametrically oppofite to thofe in the other. The ufe of thefe holes is to receive bars of iron for the retort to red on; which ftiould be, as was faid, at diffe¬ rent heights, in order to accommodate retorts of dif¬ ferent fizes. At the upper extremity of this part of the furnace, which reaches from the iron bars to the top, the heighth whereof fliould be fomewhat lefs than the width of the furnace, mud be cut a femi-circular aper¬ ture for the neck of the retort to come through. This hole muft by no means be over the doors of the fire¬ place and afli-hole; for then, as it gives paflage to the neck of the retort, it muft of courfe be oppofite to the receiver, and in that cafe the receiver itfelf would ftand over againft thofe two apertures; which would foe at¬ tended with this double inconvenience, that the receiver would not only grow, very hot, but greatly embarrafs the operator, whofe free accefs to the fire-place and afli-hole would be thereby obftrufted. It is proper therefore, that the femi-circular put we are fpeaking of be fo placed, that, when the greateft ballons are luted to the retort, they may leave an open paffage to the fire-place or afti- hole Fourthly, in order cover in the laboratory of the re¬ verberating furnace, there mud be a roof made for it in the form of a cupola, or concave hemifphere, having the fame diameter as the furnace This dome fliould have a femi-circular cut fin its rim anfwering to that above- direded to be made in the upper extremity of the fur¬ nace, fo that, when adjufted to each other, the two to¬ gether may form a circular hole for the neck of the re¬ tort to pafs through. At the top of this dome there muft alfo be a circular hole of three or four inches dia¬ meter, carrying a fliort tapering funnel of the fame dia¬ meter, find three inches high, which will ferve for a chimney C H E M I chimney to carry of? all fuliginofities, and accelerate the current of the air. This pafl'age may be (hut at pleafure with a flat cover. Moreover, as it is neceflary that the dome flipuld be taken oflP and put on with eafe, it fhould have two ears or handles for that purpofe: a portative or moveable furnace fhould alfo have a pair of handles fixed oppofite to each other between the afh hole and the fire pl>:ce. Sixthly and daftly, a conical canal muft be provided of about three foot long, and fufficiently wide at its lower end to admit the funnel of the aperture at the top of the dome. This conical tube is to be applied to the dome when the fire is required to be extremely addive : it ta¬ pers gradually from its bale upwards, and breaks off as if truncated at top, where it fhould be about two indies wide.' Befides the apertures already mentioned as neceffary to a reverberating furnace, there muft alfo be many o- ther fmaller holes made in its afll-hole, fire-place, labo¬ ratory, and dome, which muft all be fo cdhtrived as to be eafily openfed and fhut with floppies of earth : thefe holes are the regifters of the furnace, and fierce to regu¬ late the adlivity.of the'fire according to the principles before laid down When the adtion of the fire is required to be exadlly unifqrm add very briflt, it is neceffary to flop carefully with moift earth all the little.chinks in the jundlure of the dome with the furnace,. between the neck of the retort and the circular hole through which it pafles, and which it never fills exadlly, and -laftly-the holes which receive the iron bars that fuftain the retort. . It is proper to have in a laboratory feveral reverbera¬ ting furnaces of different magnitudes ; becaufe they muft be proportioned to the fi^e of the retorts employed. The retort ought to fill the furnace, fb as to leave only the diftance of an inch between it and the infide of the furnace. Yet when the retort is to be expofed to.a moft violent fire, and efpecially when it is required that the heat fhall adt with equal force on all parts of -the furnace, and as ftrongly on its vault as on its bottom, a greater diftance muft be left between the retort and the infide, of the furnace ; for then the furnace may be filled with coals, even to the upper part of the dome. If moreover fome pieces of wood be put into the afh hole, the conical ca¬ nal fitted cn to the funnel of the dome, and all ,the a- pertures of the furnace exadlly clofed, except the afh¬ hole and the chimney, the greateft heat will then be excited that this furryce can produce. The furnace now defcribed may alfo be employed in many other chemical operations. If the dome be laid a- (ide, an alembic may very well be placed therein: but then the fpace, whh h wdl be left between the body of the alembic and the top of.tbe upper part of the furnace, muft be carefully filled up with Windfor-loam moiftened ; for without that precaution the heat would foon reach the very head, which ought to be kept as cool as poflible, in order to pronjote the condenfatibn of the vapours. On this occafion therefore it will be proper to leave no •holes open in the fire-place, but the lateral ones; of Nol. II. No. 34. 3 S T R Y. 113 which alfo thofe over againft the receiver muft be’flop¬ ped. A pot or broad-brimmed earthen pan may be placed over this furnace, and being fo fitted to it as.to clofe the upper'part thereof accurately, and filled with fand, may ferve for a fand-heat to diftill with. The bars defigned to fupport diftilling veflels being ta¬ ken out, a crucible may Hand therein, and many opera¬ tions be performed that do not require the utmoft violence of fire. In a word, this furnace is one of the moft com¬ modious that can be, and more extenfively ufeful than any other. The melting furnace is defigned for applying the greateft force of heat to the moft fixed bodies, fuch as metals and earths. It is never empl'oyqd in diftilling: it is of no ufe but for calcination and fufion; and confequently need not fidmit any veffels but crucibles. The afh-hole of this furnace differs from that of the reverberating furnace only in this, that it muft be high¬ er, in order to raife the fire-place to a level with the artift’s hand; becaufe in that all the operations of this furnace are performed. The afh-hole therefore muft be about three foot high : and this height procures it more¬ over the advantage of a good draught of air. For - the fame reafon, and in confequence of the principles we laid dow^, it fhould be fo built that its width leffening infenfibly from the bottom to the top, it may be nar¬ rower where it opens into the fire place than any where below. The afh-hole is terminated at its upper end, like that of the reverberating furnace, by a grate which ferves for the bottom of the fire-place, and ought to be very fub- ftantial that it may refift the violence of the fire. The infide of this furnace is commonly an elliptic curve; becaufe it is demonftrated by mathematicians, that fur- faces having that curvature refled the rays of the fun, or of fire, in fuch a manner, that, meeting rn a point or a line, they, produce there % violent heat. But to anfwer this purpofe, thofe furfaces muft be finely polifhed ; au advantage hardly procureabl^ to the internal furface of this furnace, which can be. made of nothing but earth : befides, if’it were poffible to give ft a polifh, the violent adion of the fire that muft be employed in this furnace would prefently deftroy it. Yet the elliptical figure muft not be entirely difregarded : for, if care be taken to keep the internal furface of the furnace as fmooth as poflible, it will certainly refled the heat pretty ftrongly, and col- led'it about the center. The fire-place of this furnace ought to have but four1 apertures. Firft, that of the lower grate, which communicates with the afh-hole. Secondly, a door in its fore-fide, "through which may be introduced coals, crucibles, and tongs for managing them : this aperture fhould be made to fhut exadly with a plate of iron, having its infide coated with earth, and turning on two hinges fixed to the furnace. Thirdly, over this door a hole flaming downwards to¬ wards t he place where the crucible is to ft.and. The ufe of this hole is to give the operator an opportunity of ex- 2 F amining ii4 C H E M amining the condition of the matters contained in his cru¬ cible, without opening the door of the fire-place: this hole Ihould be made to open and Ihut eafily, by means of a Hopple of earth. Fourthly, a circular aperture of about three inches wide in the upper part or vault of the furnace, which fnouid gradually leffen Jand terminate, like that of the dome of the reverberating furnace, in a (hort conical funnel of abount three inches long, and fitted to enter the conical pipe before defcribed, which is applied when the a&ivity of the fire is- to be increafed. When this furnace is to be ufed, and a crucible to be placed in it, care mull be taken to fet on the grate a cake of baked earth fpmewhat broader than the foot of the crucible. The-ufe of this Hand is to fupport the crucible, and raife it above the grate, for which purpofe it (hould be two inches thick. Were it not for this precaution, the bottom of the crucible, which would Hand immediately on the grate, could never be thoroughly heated, becaufe it would be always expofed to the dream of cold air which enters by the aih-hole. Care {hould alfo be taken to heat this earthen bottom red-hot-bp fore it be placed in the furnace, in order to free it from any humidity, which might otherwife happen to be dri¬ ven again!! the crucible during the operation, and oc- cafion its breaking. Wc -omitted to take notice, infpeakingof the afh hole, that, befides its door, it {hould have about the middle of its height a finall hoje, capable of receiving the noftl of a good perpetual bellows, which is to be introduced into it and worked, after the door is exadly ihut, when it is thought proper to excite the activity of the fire to the utmoit violence. The forge is only a mafs of bricks of about three foot high, along whofe upper furface is directed the nofe or pipe of a pair of large perpetual bellows, fo placed .that the operator mayeafiiy blow the fire with onh hand. The coals are laid on the hearth of the forge near the nofe of the bellows ; they are confined, if necelfary, to prevent their being carried away by the wind of the bel¬ lows, within.a fpaceinclofed by bricks; and then by pull¬ ing the bellows the fire is continually kept up in its greattd activity. The forge is of ufe when there is occafion to apply a great degree of heat fuddenly to any fubftance, or when it is neceifarythat the operator be at liberty to handle frequently the matters which he propofes to fufe or calcine. The cupelling furnace is that in which gold and filver are purified, by the means of lead, from all alloy of o ther metallic fubfhmces. This furnace muft give a heat ftrong enough to vitrify lead, and therewith all the alloy which the perfeift metals may contain. This furnace is to be built in the following manner. Firfi, of thick iron-plates, or of fome fuch compofi- tion of earth as we recommended for the conftruftion of furnaces, muft be formed a hollow quadrangular prifm, whofe fides may be about a foot broad, and from ten to eleven inches high ; and extending from thence upwards may Converge towards the top, fo as to form a pyramid truncated at the height of feven or eight inches, and terminated by an aperture of the width of feven or eight I S T R Y. inches every way. The lower part of the prifm is ter¬ minated and clofed by a plate of the fame materials of which the furnace is conftru&ed. Secondly, in-the fore-fide or front of this prifm there is an opening of three .or four inches in height by five or fix inches in breadth : this opening, which {hould be very near the bottom, is the door 5f the afii hole. Immediately over this opening is placed an iron grate, the bars of which are quadrangular prifms of half an inch fquare, laid parallel to each other, and about eight or nine inches afunder, and fo difpofed that two of their angles are laterally oppofite, the two o- thers looking one direftly upwards, and the other down¬ wards. As in this lituation the bars of the grate pre- fent to the fire-place very oblique furfaces, the aihes and very final! coals do not accumulate between the r,, or hinder the free entrance of the air from the afh-hole. This grate terminates the aih-hele at its upper part, and ferves for the bottom of the fire-place. Thirdly, three inches, or three and a half, above the grate, there is in the fore fide of the furnace another opening terminated by an arch for its upper part, which confequently has the figure of a femi-circle: it ought to be four inches wide at bottom, and three inches and an half high at its middle. This opening is the door of the fire-place; yet it is not intended for the fame ufes as the door of the fire-place in other furnaces : the purpofe for which it is adually defirned {hall be explained when we come to {hew how the furnace is to be ufed. An inch above the door of the fire-place, ftili in the forefide of the furnace, ai e two holes of about an inch diameter, and at the diftance of three inches and a half from each other, to which anfwer two other holes of the fame iize, made in the hinder part, direftly oppofite to thefe. There is, moreover, a fifth hole of the. fame width a- bout an inch above the door of the fire-place. The de- ftgn of all thefe holes {hall be explained when we.defcrihe the manner in which thefe furnaces are to be ufed. Fourthly, the fore-part of the furnace is bound by three iron braces, one of which is fixed juft below the door of the afh hole ; the fecond .occupies the whole fpace between the alh-hole door and the door of the fire¬ place, and has two holes in it, anfwering to thofe which we direfted to be made in the furnace itfelf about this place; and the third is placed immediately over the door of the fire-place. Theie braces muft extend from one corner of the front of the^furnace to the other, and be faftened thereto with iron pins, in fuch a manner that their fides next to’ the doors may not lie quite clofe to the body of the furnace, but form a kind of grooves for the iron plates to Hide in, that are defigned to fiiut the two doors of the furnace when it is neceftary. Each of tfiefe iron plates {hould have a handle, by which it may be conveniently moved; and to each door there {hould be two plates, which meeting each other, and joining exa&ly in the middle of the door-place, may {hut it very clofe. Each of the two plates belonging to the door of the fire-place ought to have a hole in its upper part; one of thefe holes ihould be a flit of about two lines wide, and half an inch long ; the other may be a fenii-circular opening of one inch ia height and two in breadth.. C H E M I breadth. Thefe holes fhould be placed fo that neither of them may~open into the fire-place when the two plates are joined together.in the middle of the door to flun it clofe. ► Fifthly, to terminate the furnace above,there mufl be a pyramid, formed of the fame materials with the fur¬ nace, hollow, quadrangular, three inches high, on a bafe of feven inches, which bafe muft exadly fit the upper o- pening of the furnace? the top of this pyramidal cover mull end in a tube of three inches in diameter and two in height, which muft-be almoft cylindrical, and yet a little inclining to the conical form This tube ferves, as in the furnaces already dfferibed, to carry the conical funnel, which is fitted to the upper pair when a fire of extraordinary a&ivity is wanted. • The furnace thus conftru£ted is fit to ferve all the.pur- pofes for which it is defigned ; yfet, before it can be ufed, another piece muft be provided, which, though it does r.ot properly belong to the furnace, is neverthelefs necef-. fary in all the operations performed by it; and that is a piece contrived to contain the cupels, or other veffels which "are to be expofed. to the fire in this furnace. It is called a muffle, and is made in the following manner. On an oblong fquure, of four inches in breadth, and ■ fix or feven in length, a concave femi-cylinder is ere<5Ied, in the form of a vault, which makes a femi-circular ca¬ nal, open at both ends. One of thefe is almoft entirely clofed, except that near the bottom two-frmdl femi-cir¬ cular holes are left. In each of its fides likewife two i'uch holes are made, and the other end Is left quite open. The muffle is intended to bear and communicate the fierceft heat; and therefore it muft be made thin, and of an earth that will refift the violence of lire, fuch as that of which crucibles are made. The muffle being thus con- ftrudted, and then well baked, is fit for ufe. When it is to be ufed, it muft be put into the furnace by the upper opening, and fet upon'two iron bars, intro¬ duced through the holes made for that purpofe below the door of the fire-place. The mu$le muft be placed on thefe bars in the fire-place, in fiich a manner that its o- pen end fhall (land next to and direflly againft the door of the fire-place, and may be joined to it with lute. Then the cupels are ranged in it, and the furnace is filled up, to the height of two or three inches above the muf¬ fle, with fmall coals not bigger than a walnut, to the end that they may lie clofe round the muffle, and procure it an equal heat on every fide. The chief ufe of the muf¬ fle is to prevent the coals and afhes from falling into the cupels, w hich would be very prejudicial to the operations carnying on in them : for the lead would not vitrify as it oughr, beeaufe the immediate contaft of the coals would continually reftore its phlogifton ; or elfe the gl'afs of lead, which ought to penetrate and pafs through the cupels, would be rendered incapable of fo doing ; becaufe the alhes mixing therewith would give it fuch a confiftence *and tenacity as would deftroy that property, or at leaft confiderably lelTen ir. The openings, therefore,.which are left in the lower part of the muffle, fliould' not be fo high as to admit coals or afhes to get into the cupels-; the ufe of them is to procure an eafier pafiage for the he.at and the air to thofe veffels. The muffle is left quite S T R Y. r 15 open in its fore-part, that the operator may be at liberty to examine what paffes in the cupels, to ftir their con¬ tents, to remove them from one place to another, to con¬ vey new matters into them, &c. and alfo to promote the free accefs of the air, which muft concur with the fire towards the evaporation neceflary to the vitrification of lead ; which air, if frifh were not often enough admit¬ ted, would be incapable of producing, that effeft; becaule it would foon be loaded with fuch a quantity of vapours th.it it could not take up any more. Tne government of the fire in this furnace is founded on the general principles above laid down for all furnaces. Yet as there are fome little differences, and as it is very effential to the fuccefs of the operations for which this furnace is intended, that the artift fhould be abiblutely mafter of his degree of heat, \ye fhall in few words fhew how that may be rmfed or lowered. When the furnace is filled with coals and kindled, if . the door of the afh-hole be fet wide open, and tliat of the fire-place fhut very clofe, the force of the fire is increa- fed; and if, moreover,,the pyramidal cover be put bn the top, and the conical funnel added to it, the fire will be¬ come ftill more fierce. Seeing the matters contained in this furnace are en- compaffed with fire on all fides, except in the fore part oppofite to the door of the fire place, and as there are occafions which require that the force of the fire fhould be applied to this part alfo, an iron box, of the fhape and fize of the door, hath been contrived to anfwer that purpofe. This box is filled with lighted coals, and ap¬ plied immediately to the door-place, by which means the heat there is confiderably augmented. This help may be made ufe of at the beginning of the operation, in order to accelerate it, and bring the heat fooner to the defired de- -gtee ; or in cafe a very fierce heat be required ; or at a time when the.air being hot and moift will not make the fire burn with'the necefftr.y vigour. The heat may be leffened; by removing the jron box, and fhuttj’ng the door of the fire-place quite clofe. - It may be ftiil Further and gradually diminifhed, by taking off the conical funnel from the top ; by flnming the-dooc of the fire-place with one of its plates only/'that which has the leaft, or that which has the gr^ateft aperture in it; by taking off the pyramidal cover ; by fhutting the afh-hole door wholly or in part; and laftly; by fetting the door, of the fire-place wide'open: but, in this laft cafe, the Cold air penetrates into the cavity of the muffle, and refrigerates the cupels more than is almoft ever ne- cefiary. If it be obferved, during the operation^ that the muffle; grow's cold in any particular part, it is a figo , there is a vacuity left, by the coals in that place : in this. ■ cafe an iron wire muft be thruft into the furnace, through; the hole which is over the door of the fire place,, and the coals ftirred therewith, fo as to make them fall into their, places-and fill up the vacant interftices. It is pioper to obferve, that, befides what has been faid'concerning the ways of increafing the activity of the fire in the cupelling furnace, feveral other caules alfo may concur to procure to the matters contained in the muffle a greater degree of heat : for example, the fmaller the muffle tsk the wider and more, numerous the holes in it are.;:. u6 C H E M are ; the nearer to its bottom, or further end, the cupels are placed, the. more will the matters therein contained be affe&ed with heat. Befides the operations to be performed by the cupel, this furnace is very ufeful, and even ne'ceflary, for many chemical experiments ; fuch, for inftance, as thofe re¬ lating to fundry vitrifications and enamelling. As it is pretty low, the belt way is to place it, when it is to be ufed, on a bafe of brick-work that may raife it to a level with the operator’s hand. A lamp-furnace is exceeding ufeful for all operations' that require only a moderate, but long continued degree of heat. The furnace for working with a lamp heat is very fimple : it confifts only of a hollow cylinder, from fifteen to eighteen inches high, and five or fix in diameter, having at its bottom an aperture large efiough for a lamp to be introduced and . withdrawn with eafe. The lamp mufl have three or four wicks, to the end that by light¬ ing more or fewer of them a greater or lels degree of heat may be produced. The body of the furnace muft moreover have feveral fmall holes in it, in order to fup- ply the flame of the lampwith air enough to keep it alive. On the top of this furnace hands a bafon five or fix inches deep, which ought to fill the cavity of the cylin¬ der exafily, and to be fupported at its circumference by a rim which may entirely cover and clofe the furnace: The ufe of this bafon is to contain the fand 'through which the lamp-heat is ufually conveyed. Befides this, there muft be akind of cover or dome made of the fame material with the furnace, and of the fame diameter with the fand-bath, without any pther opening than a hole, nearly circular, cut in its lower extremity. This dome is a fort of reverberatory, which ferves to confine the heat and direft it towards the body of the re¬ tort; for it is ufed only when fomething is to be di Hilled in a veflel of this fafhion ; and then the hole at its bottom ferves for a paflage to the neck of the retort. This dome fhould hanre an ear or handle, for the conve- niency of putting it on and taking it off with eafe. Of Lutes. .Chemical veflels, efpecially fuch as are made of glafs, and the earthen veffels commonly called Hone- ware, are very fubjedl: to break when expofed to Hidden heat or cold; whence it comes that they often crack when - they begin to heat, and alfo when being very hot they happen to be cooled, either by frefii coals throwm into the furnace, or by the acce.fs of cold air. There is no way to prevent the former of thefe accidents, but by taking the pains to warm your veflel very flowly, and by wlmoH infehfible degrees. The fecond may be avoided oy coating the body of the veflel with a pafle or lute, which being dried will defend it againfl the attacks of cold. The fitteft Huff for coating veflels is a compofition of fat earth, Windfor-loam, fine fand, filings of iron, or powdered glafs, and chopped cow’s hair, mixed and made into a pafle with water. This lute ferves alfo to defend glafs veflels againfl the violence of the fire, and to prevent their melting eafily. In alm.ofl all diftillations it is of great confequence, I S T R Y. as hath been faid, that the neck of the diflilling veflel be exaftly joined with that of the receiver into which it is introduced, in order to prevent the vapours from e- fcaping into the air and fo being loft: And thisjunclion is effefted by means of a lute. A few flips of paper, applied round the neck of the veflels with common fize, will be fufficient to keep in fuch vapours as are aqueous, or not very fpirituous. If the vapours are more acrid and more fpirituous, re- courfe may be had to flips of bladder long fteeped in wa¬ ter, which, containing a fort of natural glue, clofe the jumftures of the veflels very well. If it be required to confine vapours of a Hill more pe¬ netrating nature, it will be proper to employ a lute that qiiickly grows very hard*; particularly a pafle made with quick-lime and any fort of jelly, whether vegetable or animal ; fuch as the white of an egg, ftiff fize, &c. This is an excellent lute, and not eafily penetrated. It is alfo ufed to. flop any cracks or fradtures that happen to glafs veflels. But it is not capable of refifting the vapours of mineral acid fpirits, efpecially when they are ftrong and fmoking : For that purpofe it is neceffary to incorporate the other ingredients thoroughly with fat earth foftened with water ; and even then it frequently happens that this lute is penetrated by acid vapours, efpecially thofe of the fpirit of fait, which of all others are confined with the grsateft difficulty. In fuch cafes its place may be fupplied with another, which is called' fat lute, becaufe it is aftually worked up with fat liquors. This lute is compofed of a very fine cretaceous earth, called tobacco-pipe clay, moiftehed with equal parts of the drying oil of lint-feed, and a varnifh made of amber and gum copal. It muft have the confiftence of a ftiff pafte. When the joints of the veffels are clofed up with this lute, they may, for great-, er fecurity, be covered over with flips of linen fmeared with the lute made of quick-lime and the white of an egg. Chemical vcffels' are liable to be broken in an opera¬ tion by other caufes befides the Hidden application of heat or cold. It frequently .happens that the vapours of the matters, expofed to the aiftion of fire, ruffi out with Hich impetuofity, and are fo elaftic, that finding no paf- fage through the lute with which the joints of the .veffels are clofed, they burft the veffels themfelves, fometimes with explofion and danger to the operator. To p'revent this inconvenience, it is neceffary, that in every receiver there be a fmall hole, which being flopped only with a little lute may eafily be opened and ffiut again as occafion requires. It ferves for a vent-hole to let out the vapours, when the receiver begins to be too much crowded with them. Nothing but practice can teach the artift when it is requifite to open this vent. If he hits the proper time, the vapours commonly ruffi out with ra¬ pidity, and a confiderable biffing noife ; and the vent fhould be flopped again as foon as the hifling begins to grow faint. The lute employed to flop this fmall hole ought always to be kept fo du&ile, that by taking the fi¬ gure of the hole exaftly it may entirely flop it. Befides, if it ffiould harden upon the glafs, it would flick fo faft* that it would be very difficult to remove it without break¬ ing TlateXW fk l y i GeOIFROYS TaRZJZ oftie CoMPARATJO^AP^ITIESo^^Sc^eaL/undry M/tonccs. Plate J^S i. ii m. A7: tl tie m idc x ig, m m ^r: ©^r1 2f. v MS 9 *(D 9 k o ^ ©r .913. v o 9 3 V •(Eh >® -e ©y •© >® *© ©- MS •© >® *© 4 ■® * . //„ ExpIaiLatiorn of fheOiamcter /j'/f/' fayX* ^ Ght^/S^^rA' ^ ^ /bteuty Q rT /arr/iY*7U'/r/ ©*^ ^ftet?i/hwof{/n//rrfv7tt/3* ^roit ‘ ^ ^ Q)pU2 7 ©V d 9 5 o k 9 3 ^ §. o L 3 9 ILC 9 j k .9 d* i L T KD' fJZ&'w e wsr vr rUM iHl, UJ (a/amttu. ^prA,p/,n^f,r W/nfr,^ ‘ Of \ <-G,„/'"Nitrous Acirr. To extre/d> nitre out of nitrous earths and femes. Tie, purijicati.on: cf fait pet re. ^ Mother of nitre. Mag- nefia. Take any quantity of nitrous earths or flones; re¬ dder them to powder; and therewith mix a third part of* the' allies of green wood and1 quick-firne. Put this mixture into a barrel or vat, and pour on it hot water to about-twice the weight of the whole mafs Let it llaud thus for twenty four hourq, flirring it from time to time Wiclt a flick. Then filter the liquor through brown pa¬ per, or pals it through a flannel bag, till it come clear: it will then have a yellowilh colfcur. Boil this liquor, fifed 'evapeirate till yqu perceive that a drop of it let fill on any dbld bodycoagulates. Then flop the evaporation, and’let yotfr liquor in a cool place. In the fpace of four arid twenty hours cryflals will be formed in it, the figure of which is that of an hexagonal prifm, . having its oppo- fite planes generally equal, and terminated at each ex¬ tremity by a pyramid of the fame number of fides. Thefe 'cryflals will be of a brownilh colour, and deflagrate on. a li ve coal. Decant the liquor from thefe Cryflals; mix' it with twice.; ISO C H E M I twice its weight of hot water 4 evaporate and cryftallife as before. Repeat the fame operation till the liquor will yield no more cry Hals: it will then be very thick, and goes by the qame of mother of nitre. Earths and Hones that have been impregnated with a- nimal or.vegetable juices fufceptible of putrefaction, and have bS^en longexpofed to the air, but Iheltered from the fun and rain, are thofe which yield the greateli quantity of nitre. But all forts of earths and Hones are not equally fit to produce it. None is ever found in flints or fands of a cryfialline nature Some earths and Hones abound fo with nitre, that it ef- florefces fpontaneoufly on their furface. in the form of a cryfialline down This nitre may be collected with brooms, and accordingly has the name of falt-petre fweepings. Some of this fort is brought from India The procefs by which our falt-petre makers extraft nitre in quantities, out of rubbifh and nitrous earths, is very nearly the fame with that here fet down : fo that we {hall not enter into a particular account of it. We (hail only take notice of one thing, which it is of fdme confe quence to know; namely, that there is no nitrous earth which does not contain fea fait alfo. The greatefi quan¬ tities of tins fait are to be found in thofe earths which have been drenched with urine or other animal excre¬ ments Now, as the rubbifh of old houfes in great ci¬ ties is in this clafs, it comes to pafs, that when the fait petre workers evaporate a nitrous lixivium drawn from that rubbifh, as foon as the evaporation is brought to a certain pitch, -a great many little dryfials of fea-falt form in the liquor, and fjll to the bottom ot the veffel. The falt-petre workers in France call thefe faline par¬ ticles the grain, and take great care to feparate them from the liquor, (which as long as it continues hot keeps the falt-petre diffolved) before they fet it to cryfiallife. This faCt feems a little lingular confidering that fea-falt diffoives in water more eafily than falt-petre, and cry fiallifes with more, difficulty In order to difcover the caufe of this phenomenon, we tnufi recoiled, firfi, that water can keep but a deter minate quantity of any fait in folution, and that if water fully faturated with a fait be evaporated, a quantity of fait will cryfiallife in proportion to the quantity of water evaporated. Secondly, that thofe fait1 which are the mofi foluble in water, particularly thofe which run in the air, will diffolve in cold and in boiling water equal¬ ly : whereas much greater quantities of the other falls will diffiolve in hot and boiling water than in cold water. Thefe things being admitted, when we know that fea- falt is one of the firfi fort, and fait petre of the fecond, the reafdn why fea-falt precipitates in the preparation of falt-petre appears at once. For,. When the folution of falt-petre and fea fait comes to be evaporated to fuch a degree that it contains as much fea -fait as it poffibly can, this fait muft begin to cryftallife, and continue to do fo gradually as the evaporation advances But becaufe at the fame time it does not contain as much fait peireas it can hold, feeing it is capable of diflblving a much greater quantity thereof when it is boiling hot than when it is cold, this laft named fait will not cryftallife fo foon. If the evaporation were continued till the cafe S T R Y. of the {»lt-petre came to be the fame with that of the fea fait, then the falt-petre alfo would begin to cryftallife gradually in proportion to the water evaporated, and the two falts would continue cryftallifing promifcuonfly toge¬ ther : but it is never carried fo far; nor is it ever necelfary; for as the water, cools it becomes more and more inca¬ pable of holding in fol»tion the fame quantity of falt-petre as when it was boiling hot. And then comes the very reverfe, with regard to the cryftallifing of the two falts; for then the falt-petre {hoots, and not the fea-ialt. The reafon of this fadf al¬ fo is founded on what has juft been faid The fea fait, of which cold water will diffoTve as much as boiling wa¬ ter, and which owed its cryftallifing before only to the evaporation, now ceafes to cryftallife as foon as the eva¬ poration deafes; while the fait petre. which the water kept diffolved only becaufe it was boiling hot, is forced to cryftallife merely by the cooling of the water When the folution of falt-.petre has yielded as man/ cryftals of that fait as it can yield by cooling, it is again evaporated, and being then fuffered to cool yields more cryftals And thus they continue evaporating and cry- ftallihng till the liquor will afford no more cryftals. It is plain, that as the falt-petre cryj^allifes, the pro¬ portion of fea-falt to the diffolving liquor increafes ; and as a certain quantity of water evaporates alfo during the time employed in cryftalUfing the falt-petre, a quan¬ tity of fea-falt, proportioned to the water fo evaporating, muft cryftallife in that time: and this is the reafon why falt-petre is adulterated with a mixture of fea-falt. It likewife follows, that the laft cryftals of nitre, obtained from a folution of fait petre and fea-falt, contain much more fea-falt than the firft. From all that has been faid concerning the cryft ; lifa- tion of falt-petre and fea-falt, it is eafy to deduce the proper way of purifying the former «f thefe two fairs from a mixture of the latter. For this purpofe the falt- petre to be refined need only be diffolved in fair water. The proportion between the two falts in this fecond fo¬ lution is very different from what it was in tfie former; for it contains no more fea-falt than what had cryftal- lifed along with the falt-petre under favour of the evapo¬ ration, the reft having been left diffolved in the liquor that refufed to yield any more nitrous cryftals. As there is therefore a much greater quantity of falt- petre than of fea-falt in this fecond folution, it is eafy to evaporate it to fuch a degree that a great deal of falt- petre ffiali cryftallife, while much more of the water muft neceffarily be evaporated before any of the fea-falt will cryftallife. However, the falt-petre is not vet entirely freed from all mixture of fea fait by this firft purification; for the the cryftals obtained {rom this liquor, in which fea-falt is diffolved, are ftill incrufted, and, as it were, infedted therewith : hence it comes, that, to refine the falt-petre thoroughly, thefe cryftallifations muft be repeated four or five times. The falt-petre men commonly content themfelves with cryftallifing it thrice, and call the produce falt-petre of the firft, fecond. or third ffioot, according to the num¬ ber of cryftallifations it has undergone. But their beft refined CHE M I refined fa!t p.etre, even that of the third fliooting, is nor yet fytFiCienfly pure for chemical experiments that require much accuracy: fo that it mult be further purified, but fiill by the fitme method. The nitrous acid is not pure in the earths and /tones from which it is extracted. It is combined partly with the' very earth in which it is formed, and partly with the volatile alkali produced by the putrefadtion of-the vege¬ table or animal matters that concurred to its generation. A fixed alkali and quick-lime are added to thedixivium of a nitrous earth, in order to decompofe the nitrous falts formed in that earth, and to feparate the acid from the volatile alkali and the abforbent earth with which it is united: thence conies that-copious fediment which ap¬ pears in the lye at the beginning of the evaporation. Thefe matters form with that acid a true nitre, much more capable than the original nitrous falts of cry- ftallifation, detonation, and the other properties which are eflential thereto. The bafis of nitre is therefore a fixed ■ alkali mixed with a little lime. The mother of nitre, which will yield no morejcryfials, is brown and thick: by evaporation, over a fire it is fur' ther infpiflated, and becomes a dry, folid ,body; which however being left to kfelf fodn gives., ;and runs into a liquor. This water Hill contains a good deal of nitre, fea-falt, and the acids of thefe falts united with an ab forbent earth. It contains moreover a great deal of a fat, vifcid matter, which prevents its cryfiailifing. All faline folutions in general, after having yielded a certain quantity of cryftals, grow thick, and refufe to part with any more, though th«y Hill contain much fait. They are all called motber-’wattrs, as well as that, which hath yielded nitre. The mother-waters of different (alts may prove the fubje&s of curious and ufeful enquiries. If a fixed alkali be mixed with the mother of nitre, a copious white precipitate immediately falls, which being colledted and dried is called nregnejia. This precipitate is nothing but the abforbent earth that was united with the nitrous acid, together with a good deal of the lime that'was added, and was alfo united with that acid, from which they are now feparated by the fixed alkali, according to the ufual laws of affinities or eleftive at- traftions. * The vitriolic acid poured upon mother of nitre caufes many acid vapours to rife, which are a compound of the nitrous and marine- acids, that is, nn aqua regia. On this occafion alfo there falls a large quantity of a white.! powder, which is Hill called magnefta\ yet it differs from the former in that it is not, like it, a pure abfor¬ bent earth, but combined with the vitriolic acid. An aqua regis may alfo be drawn from nitrous earths by the force of fire only, without the help of ^ny ad- ditamefff. To decompofe Nitre hy means of the Phlogiflen. Nitre fisted by Charcoal. 1 Clyffus of Nitre. Sal Polychreltum. Take the purefi falt-petre in powder5 put it into a large Crucible, which it mav but half fill; fet the crucible in a common furnace, and fm round it with coals. When it is red-hot the nitre will melt, and become as fluid as Vol. II. No. 35. 3 S T R Y. 121 water. Then throw iiito the crucible a finall quantity o'f charcoal dull : the nitre am} the cjiarcqal will imme¬ diately, deflagrate with vielenpe; and a great cominotidn will be raifed-, accornpanied with a conficierabls, hi fling, and abundance of black fmoke. As. the charcoal waffes, the detonation will'a^ate, and ceafe entirely as foon as the coal is quite cpnfumed Then throw into 'thp crucible the fame quantity of charcoal-duff as before, and the fame phenomen’a will be repeated Let this eqal alfo be confumed : then add more, and go on in the fame manner till you can excite no fur¬ ther deflagration , always obferving to let the burning coal be entirely confumed before you add any frefli. \Vhen no deflagration enfues, the matter coptamedin the cruqble will have loft much of its fluidity. Nitre will not take fife, unlefs the inflammable matter added to,it be a^foally burning, or the nitre itfelf fed hot, and fo thoroughfy ignited as immediately to kindle it. Therefore, if you would procure the detonation of nitre with charcoal, and make ufe of cold charcbal; as in the prpeefs, the nitre in the crucible mull be red hot;'arid in perfect fufion: but you may alfo ufe live coals, and then the nitre need not be red hot. The matter remaining in the,crucib]e after the opera¬ tion, is a very Hrong fixed alkali. Being expoied to the air, it quickly extratfls-the moiffufe thereof,-and j funs into a liquor. It is called alkalizated nitret or to: di- flinguiffi it from nitre alkalizated by otlief inflammable matters, nitre fixed by charcoal. The nitrous acid is not only diifipated during the de¬ flagration of the nitre, but is even deftroyed, and per¬ fectly decompofed. The finoke that rifes duririg the operation has not the leafl odour of an acid. Li order to colleCt the vapours difeharged by the de¬ flagration of nitre,, fit to a tubulated earthen retort UV6 or three large adopters : fet the retort in a furnace ; and under it make a fire fuffkient to keep its bottom mode¬ rately red. Then take a friiall quantity, two-or three pinches for example, of a mixture of'three parts of mtre with one of charco^l-dufl, arid drop it into the ffetort through its tube, which muH be uppermoH/and immedi¬ ately Hopped clofe. A detonation inHantly enfues, and the vapours that rife from the inflammed mixture of nitre and charcpal, paffirig out through the'peck of the retort into the adopters,, circulate therein for a while, and at lafl condenfe. into a liquor.1 When the detonation is over, and the vapours ripn- denfed, or nearly fo, drop into the retort another ecfual quantity of the mixture - and repeat this till, you find there; is liquor enough in the fecipients to be examined with eafe and accuracy. This liquor is almofi infipid, and Ihews no tokens of acidity; of at moH but very flight ones. It is called c'tyfus of nitre. Nitre is alfo decompofed and takes fire by the means of fulphur; but the circumHances and the refult differ widely from thofe' produced therewith by charcoal or any oth^r inflammable body. Nitre deflagrates with fulphur on account of the phlo- giflon which the latter contains. If one part of fulphur be mixed with two ot three parts of nitre, and the mix¬ ture thrown by little and little into a red-hot crucible, 2 H upon i22 (THEM upon every projedtion there arifes a detonation accom¬ panied with a vivid flame. The vapours difcharged on this occafion have the mingled fmell of a fulphureous fpirit and fpirit of nitre; and if they he colledted by means of a tubulated retort, and fuch an apparatus of veflels as was ufed in the pre¬ ceding experiment, the liquor contained in the recipients is found to be an adtual mixture of the acid of fulphur, the fulphureous fpirit, and the acid of nitre; the firfl: be¬ ing of greater quantity than the other two, and the fe- cond greater than the laft. Nor is the remainder after detonation a fixed alkali, as in the former experiments ; but a neutral fait, confid¬ ing of the acid of fulphur combined with the alkali of nitre ; a fort of vitriolated tartar, known in medicine by the name of fal polycbrejlum. To*dccompofe Nitre by means of the Vitriolic Acid. The Smoking Spirit of Nitre. Sal de duobus. The Purification of Spirit of Nitre. Take equal parts of well purified nitre and green vi¬ triol: dry the nitre thoroughly, and bruife it to a fine powder. Calcine the vitriol to rednefs : reduce it like- wife to a very fine powder; and mingle thefe two fub- ftances well together. Put the mixture into an earthen long neck, or a good glafs retort coated, of fuch a fize that it may be but half full. Set this veflfel in a reverberating furnace covered with its dome; apply a large glafs receiver, having a fmall hole in its body, flopped with a little lute. Let this re¬ ceiver be accurately luted to the retort with the fat lute, and the joint covered with a flip of canvas fmeared with Jute made of quick-lime and the white of an egg. Heat the veffels very gradually. The receiver will foon be filled with very denfe red vapours, and drops will begin to diflill from the nofe of the retort. Continue the diftillation, increafing the fire a little ■when you obferve the drops to follow each other but (lowly, fo that above two* thirds of a minute paffes be¬ tween them; and, in order to let out the redundant va¬ pours, open the fmall hole in the receiver from time to time. Towards the end of the operation raife the fire fo as to make the retort red. When.you find that, even when the retort is red-hot, nothing more comes over, unlute the receiver, and without delay pour the liquor it contains into a cryftal bottle, and clofe it with a cry- flal flopple rubbed in its neck with emery. This liquor will be of a, reddifh yellow colour, fmoking exceedingly, and the bottle containing it will be conflamly filled with red fumes like thofe obferved in the receiver. By the proeefs here delivered, a very flrong, perfe&ly dephlegmated, and vaflly fmoking fpirit of nitre is ob¬ tained. , When the operation is over, you will find a red mafs at the bottom of the retort, cafl as it were in a mould. This is a neutral fait of the nature of vitriolated tartar, refulting from the union of the acid of the vitriol with the alkaline bafis of the nitre. The ferruginous bafis of the vitriol, which is mixed with this fait, gives it the red colour. To feparate it therefrom, you muft pulverife it, difiblve it in boiling I S T 11 Y. water, and filter the folution feveral times through brown paper ; becaufe the ferruginous earth of the vitriol is fo fine, that fome of it will paftf through the firft time. When the folution is very clear, and depofites no iedi- ment, let it be fet to Ihoot, and it will yield cryftals of vitriolated tartar ; to which chemifts have given the pe¬ culiar title of fal de duobus. Nitre may alfo be decompofed, and its acid obtained, by the interpofition of any of the other vitriols, alums, gypfums, boles, clays ; in (hort, by means of any com¬ pound in which the vitriolic acid is found, provided it have not a fixed alkali for its bafis. The diflillers of aqua fortis, who make large quanti¬ ties at a time, and who ufe the leaft chargeable methods, do their"bufinefs by the means of earths impregnated with the vitriolic acid ; fuch as clays and boles. With thefe earths they accurately mix the nitre from which they in¬ tend to draw their fpirit: tins mixture they put into large oblong earthen pots, having a very (hort curved neck, which enters a recipient of the fame matter, and form. Thefe veflels they place in two rows oppofite to each o- ther in long furnaces, and cover them'over with bricks cemented with Windfor-loam, which ferves for a rever¬ beratory: then they light the fire in the furnace, making it at firft very fmall, only to warm the veffels; after which they throw in wood, and raife the fire till the pots grow quite red-hot, in which degree they keep it up till the diftillation is entirely finifhed. Moft experiments require the fpirit of nitre to be ab- folutely pure ; and if it be intended for fuch, it muft be perfectly cleanfed from the vitriolic taint. . This is eafily eflFefted by mixing your fpirit with very pure nitre, and diftiiling it a fecond time. The vitriolic acid, with which this fpirit of nitre is adulterated, coming in contaft with a great quantity of undecompofed nitre, unites with its alkaline bafis, and expels a propor¬ tionable quantity of the nitrous acid. Of the Marine Acid. ' To extraft Sea-fdt from Sea-water, and from Brine- fprings. Epfom Salt. Filter the falt-water from which you intend to ex- trad the fait ; evaporate it by boiling, till you fee on its furface a dark pellicle : this confifts wholly of little cry¬ ftals of fait juft beginning to (hoot : now (lacken the (ire, that the brine may evaporate more (lowly, and without any agitation. The cryftals, which at firft were very fmall, will become larger, and form hollow truncated pyramids, the apices whereof will point downwards, and their bafes be even with the furface of the liquor. Thefe pyramidal cryftals are only colledions of fmall cubical cryftals concreted into this form. When they have acquired a certain magnitude they fall to the bottom of the liquor. When they come to be in fuch heaps as almoft to reach the furface of the liquor, decant it from them, and continue the evaporation till no more cryftals of fea-falt will (hoot. The acid of fea-falt is fcarce ever found, either in fea- water or in the earth, otherwife than united with a fixed alkali C H E M alkali of a particular kind, which is its natural bafis; and confequently it is in the form of a neutral fait. This fait is plentifully dilfolved in the waters of the ocean, and when obtained therefrom bears the name of fea-falt. It is alft> found in the earth in vaft cryllalline mafi’es, and is then called fal-gem ; fo that fea-falt and fal-gem are but one and the fame fort of fait, differing very little from each other, except as to the places where they are found. In the earth are alfo found fprings and fountains, whofe waters are ftrong brines, a great deal of fea-falt being diffolved in them. Thefe fprings either rife di- redtly from the fea, or run through fome mines of fal- gem, of which they take up a quantity in their paffage. As the fame, or at leaft nearly the fame quantity of fea-falt will continue diffolved in cold water as boiling water will take up, it cannot fhoot, as'nitre does, by the mere cooling of the water in which it is diffolved : it cryftallifes only by the means of evaporation, which con¬ tinually leffens the proportion of the water to the fait; fo that it is always capable of containing juft fo much the lefs fea-falt the more there is cryftallifed. The brine fhould not boil after you perceive the pel¬ licle of little cryftals beginning to form on its furface ; for the calmnefs of the liquor allows them to form more regularly, and become larger. Nor after this flrould the . evaporation be hurried on too faft; for a faline cruft would form on the liquor, which, by preventing the va¬ pours from being carried off, would obftruft the cryftal- lifation. If the evaporation be continued after the liquor ceafes to yield any cryftals of fea-falt, other cryftals will be obtained of an oblong four-fided form, which have a bit¬ ter tafte, and are almoft always-moift. This fort of fait is known by the name of Epfom fait, which it owes to a fait fpring in England, from the water of which it was firft extraded. This fait, or rather faline compound, is a congeries of Glauber’s fait and fea-falt, in a manner confounded together, and mixed with fome of the mo¬ ther of fea-falt, in which is contained a kind of bitu¬ minous matter. Thefe two neutral fairs, which confti- tute the Epfom fait, may be eafily feparated from each other, by means of cryftallifation only. Epfom fait is purgative and bitter ; and therefore named _/«/ catharti cum amarum, or bitter purging falts. There are different methods ufed in great works for obtaining fea-falt out off water in which it is diffolved. The fimpleft and eafieft is that pradifed in France, and in all thofe countries which are not colder. Qn the fea- fhore they lay out a fort of broad (hallow pits, pans, or rather ponds, which the fea fills with the tide of flood. When the ponds are thus filled, they ftop their commu¬ nication with the fea, and leave the wafer to evaporate by the heat of the fun ; by which means all the fait con¬ tained in it neceflarily cryftallifes. TheE pits are called fait ponds. - Salt can be made in this v/ay in the fummer- time only, at leaft in France, and other countries of the fame temperature ; for during the winter, when the fun has lefs power,, and rains are frequent, this method is not praflicable. For this reafon, as it often rains in the province of I S T R Y. 123; Normandy, the inhabitants take another way to extrafh fait from fea-water. The labourers employed for this purpofe raife heaps of fand on the (hore, fo that the tide waters and drenches them when it flows, and leaves the fand dry when it ebbs. During the interval between two tides of flood the lun and the air eafily carry off the moifture that was left, and fo the fand remains impreg¬ nated with all the fait that was contained in the evapo¬ rated water. Thus they let it acquire as much fait as it can by feveral returns of flood, and then wafh it out with frefti water, which they evaporate over a fire in leaden boilers. To obtain the fait from brine-fprings, the water need only be evaporated : but as feveral of thefe fprings con¬ tain too little fait to pay the charges that would be iir-j. curred, if the evaporation were effesfled by the force of fire only, the manufaflurers have fallen upon a lefs ex- penfive method of getting rid of the greafeft part of the water, and preparing the brine for cryftallifation, in much lefs time, and with much lefs fire, than would otherwife have been neceffary. The method confifts in making the water fall from a certain height on a great many fmall fpars of wood, which divide it into particles like rain. This is perform¬ ed under (beds open to all the winds, which pafs freely through this artificial flrower. By this means the water prefents to the air a great extent of furface, being in¬ deed reduced almoft entirely to .furface, and the evapo¬ ration is carried on with great cafe and expedition. The water is raifed by pumps to the height from which it is intended to fall. Experiments concerning, the decompcftion of Sea-falt, by means of the phlogifton. KunckelV Phofphcrus. “ Of pure urine that has fermented five or fix days- take a quantity in proportion to the quantity of phofpho- rus you intend to make : it requires about one third part of a hogftiead to make a dram of phofphorus; Evaporate it in iron pans, till it become clotted, hard, black, and nearly like chimney foot; at which time it will be re¬ duced to about a fixtieth part of its original weight be¬ fore evaporation. “ When the urine is brought to this condition, put it in feveral portions into fo many iron pots, under whi:h you, muft keep a pretty bride fire fo as- to make their bot¬ toms red, and ftir it inceffantly till the volatile fait and the fetid oil be almoft wholly difiipated, till the matter ceafe to emit any fmoke, and till it fmell like peach- bloffoms. Then put-out the fire, and pour on the mat¬ ter, which will now be reduced to a powder,- fomewhat more than twice its weight of warm water. Stir it about in this water; and leave it to fo .k therein for twenty- four hours. Pour off the water by inclina'ion ; dry the drenched matter; and pulverife it. The previous cal¬ cination carries off from the matter about a third of its weight, and thelixiviation waftres out half the remainder. “ With what remains thus calcined,. waftted, and dried, mix half its weight of gravel, or yellow free- ftone rafped, having fifted out and thrown away all the fineft particles. River-fand is not proper on this occa- fion, becaufe it flies in a hot fire. Then add to this mixture: 124 c H E M mixture a fixteenth part of its weight of charcoal, made ,of beech, or of any other wpod except oak, becaufe that alfa flies, Maiftep the wh$)e with as much water as will bring it-ta a ftiff by , wor]cing and kneading it with •your.hjwds ::,Now iptrodupe it into ypur retort, taking care; not to daub its. neck. The retort muft be of the belt earth, and of fuch a fize, that when your matter is in it,; a full-third thereof lhall tlill be empty. “ Place your retort, thus charged, in a reverberating furnace, fo proportioned, that, there may be an interval •of t wo inches all round between the fides of the 'furnace sand the bowl pf the retort, even where it contrails to -form the neck, winch mould Hand inclined at an angle of lixty degrees . Stop all the apertures of the furnace, .except the doprs of.the. fire place and, aflj:hole. • ' “ Fit on to the retort a large glafs balfpn two thiids full of water,, and lute.them together, as in diffilfib^ the Imokmg fpirit of, nitre. In, the hinder part of this bal¬ lon, a little above,the furface of the yyatcr, a fmall hole muff be bared. This bole is todt? popped, witha fmall peg of birch-wood, which mull flip in ane! out very ea- Idy, and have a fmall knob to, prevent its falling into the • ballon. This,-peg is.to.be^pulied.p^,. fromtipne to.time, that by applymg the hand to the,bdlp, jt may be‘known* whether the air larufitd by the heat of the retort, iifues,. -out with tooriuuc'11:®1't0P Htde . “ If> die air rttihea out . with too, njpeh rapidhy, and .with a bifling noile, the dqoc of.the'aflidjore muft be bn- ttrely fhutj in order aodfiackeii the fir?. If it do not firjke pretty furartly agamtl the hand, that dpor mull be' opened wider j: and large.coals thrown into the fire-place to quicken the fire immediately. “ The operation ufaally Jails four and twenty hours; and the, following figns^fhew that it will fucceed, provi¬ ded the retort reflif the ^re-; “ -You mud begin ^the operation with putting forpe un-; lighted charcoal in the a.Ii hole, and a little lighted char¬ coal at the door thereof, pi order to warm the retort ve¬ ry flowly. When,tge :Wbole is kindled, pulh it into the •alh hole, and dole .the door therepf with a tile. This -rnodtrate heat brings; over .the .phlegm of the mixture. The fame degree of heat.mud be kept up four hours, after which forne coals may be laid on the grate of the fire¬ place, which the fire underqeath, will kindle by degrees. With this fecond heat brought nearer the retort, the bal¬ lon grows wuirm, and is filled with white vapours which have the fmell of fetid oil In four hours after, this vef- fd will grow;cool and clear ; and then you mud open the door of the afh-hole one inch, t row frefli coals into the -fire- place every- ,three minutes,, and every time fhut the door of it, left ,tho cold air from without fliould fli ike a- gaind the bo tom of the retort and crack it “ When the fire has ' een kept“up to this .degree for about two hours, the infide of the ballon begins to be netted over with a volatile fait of a Angular nature, which cannot be driven up but by a very violent fire, and which fmells pretty drong of peach-kernels. Care mud be t iken that this concrete fait do not dop the little hole in the ballon : for in that cafe it would burft, the re¬ port being then red-hot, and the air exceedingly rarefied. The. water in the ballon, being heated by the vicinity of I S T R Y. the furnace, exhales vapours which diffolve this fprigged fait, and the ballon clears up in half an hour after it has ceafed rifing. ‘‘ In about three hours from the firft appearance of this fait, the ballon is again filled with new vapours, which fmell like fa! ammoniac thrown upon burning coals. They condenfe on rhefides of the receiver into a fait which is not branched* like the former, hut appears in long per¬ pendicular dreaks, which the vapours of the water do not diffolve. Thefe white vapours, are the fore-runners of the phofphorus; and a little before they ceafe to rife they lofe their fird fmell of fal ammoniac, and acquire the o- dour of garfick. “ As they afeend with .great rapidity,, the little hole mhd be frequently opened, to obferve whether the bif¬ fing be-; not tod' itrdng - for in that cafe it would be ne- ceffary to {hut the door of. the alh-bole quite clofe. Thefe White vapours continue two hours. When you find they ceale rifing, make a fmall paflage through the dome, by'Opening foftie of its regiders, that tlie flame may'jud begm to draw,- Keep up the fire in tfais mean ftFFthe fird4ivolatile phofphorus begin to appear. ! This appears-in about three', hours after the white va^duff fi/d-ibegin to Vife. In order to difeover-it, pull Out'the*little birchen peg once every minute, and rub it ag’ainA fome hot part of he furnace, where it will leave a trail of Kght, if there.be any phofpborus upon it “ : Sqoh a'ftef' you - obferve this fign, there will iflue out thrbhgfi thefittle* hole-Ctf the ballon a dream of blu- ifli light, 'WBreh^cdritlnues'-of a greater or fltorter extent to the end of the operation. This:dream or fpout of light does not burn If you hold your finger againd it for twenty of thirty fecond^,- the light will adhere to it; and if you rub that finger over your hand, the light will befmbar it, and render it luminous. “ But from time to time this dreamer darts out to the length of feven of eight inches, fnapping and emit¬ ting fparks, of fire; and then it burns ail combudible bo¬ dies that come in its- way. When you obferVe this, you mud manage the fire very warily,- and Unit the door of the a£h-hole quite clofe, yet without ceafing to throw coals into the fire place every two minutes. “ The volatile phofphdrus continues two hours ; after which the little fpout of light contrails to the length of a line or two : Arid ndw is the time for pulhing your fire to the utmod : Immediately fet the door of the afti hole wide open, throw billets of wood into it. uhdop all the re¬ giders of the reverberatory, fupply the fire-place with large coals every minute : In Ihort, for fix or feveh hours all the infide of the furnace mud be kept of a white heat, fo that the retort Avail hot be didinguiflvable. ‘‘/In this fierce extremity of heat the true phofphorus didills like an oil, or like melted wax : One part thereof floats on the water in the recipient, the other falls to the bottom. At lad the operation is known to be quite o- ver when the upper part of the ballon, in which the vo¬ latile phofphorus appears condenfed in a blackiflr film, begins to grow red : For this fhews that the phofphorus is burnt where the red fpot appears You mud now dop all the regiders, and flmt all the doors of the furnace, in order to fmotber the fire; and then clofe up the little hole C H E M in the ballon with fat lute orbees-wax. In this condition the whole muft be left for two days-, becaufe the ve/Tels mult not be feparated till they are perfectly cold, lell the phofphorus fhould take fire. “ As foon as the fire is out, the ballon, which is then in the dark, prefents a moft agreeable objeft: All the empty part thereof above the water feems filled with a • beautiful blue light; which continues for feven or eight hours, or as long as the ballon keeps warm, never dif- appearing till it is cooled. “ When the furnace is quite cold, take out the vef- fels, and feparate them from each other as neatly as pof- fible. With a linen cloth wipe away all the black ftulf you find in the mouth of the ballon ; for if that filth fhould mix with the phofphorus, it Would hinder it from being tranfparent when moulded. This muft be done with great expedition : After which pour into the ballon two or three quarts of cold water, to accelerate the pre¬ cipitation of the phofphorus that fwims at top. Then agitate the water in the ballon, to rinfe out all the phof¬ phorus that may ftick to the fides ; pour out all the wa¬ ter thus fliaken and turbid, into a very dean earthen pan,- and let it ftand till it grows clear. Then decant this firft ufelefs water, and on the blackilh fediment left at the bottom of the pan pour fome boiling water to melt the phofphorus ; which thereupon unites with the fuli¬ ginous matter, or volatile phofphorus, that precipitated with it, both together forming a mafs of the colour of flate. When this water in which you have melted the phofphorus is cool enough, take out the phofphorus, throw it into cold water, and therein.break it into little bits in order to mould it. “ Then take a matras, having a long neek fomewhat wider next the body than at its mouth: Gut off half the body, fo- as to make a funnel of the neck-part, the fmaller end of which muft be flopped with a cork. The .firft mould being thus prepared, plunge it endwife,■ with its mouth uppermoft, in a veflel full of boiling water, and fill it with that water. Into this funnel throw the little bits of your flate-like mafs, which will melt again in this hot water, and fall fo melted to the bottom of the .tube. Stir this melted matter with an iron wire, to pro¬ mote the feparation of the phofphorus from the fuligi¬ nous matter with which it is fouled, and which, being lefs ponderous than the phofphorus, will gradually rife a- bove it towards the upper part of the cylinder. “ Keep the water in the velfel as hot as at firft, till on taking out the tube you fee the phofphorus clean and tranfparent. Let the clear tube cool a little, and then fet it in cold water, where the phofphorus will congeal as it cools. When it is perfe&Iy congealed, pull out the cork, and with a fmall rod near as big as the tube, pulh the cylinder of phofphorus towards the mouth of the fun¬ nel, where the feculency lies. Cut off the black part of the cylinder, and keep it apart: For when you have got a quantity thereof, you may melt it over again in the fame manner, and feparate the clean phofphoms which it ft ill contains. As to the reft of the cylinder which is clean and tranfparent, if you intend to mould it into, fmaller cylinders, you may cut it in flices, and melt it Vol.II. No. 35. 3 I S T R Y. 125 again by the help of boiling water in glafs tubes of fmal- er dimenfions.” It is proper to obferve, in the firft place, that one of the moft ufual caufes of mifcarriage in this operation is a defedt of the requifite qualities in the retort employed. It is abfolutely neceflary to have that velfel made of the beft earth, and fo well made that it fhall be capable of refilling the utmoft violence of fire, continued for a very long time. We lhall, in the fecond place, obferve withM. Hellot, “ that, before you fet your retort in the furnace, it is proper to make an elfay of your matter, to fee if there be reafon to hope for fuccefs. For this purpofe put a- bout an ounce thereof into a fmall crucible, and heat it till the veflel be red. The mixture, after having fmo- ked, ought to chop and crack without puffing up, or e- ven rifing in the leaft. From thefe cracks will iflue un¬ dulated flames, white and bluilh, darting upwards with rapidity. This is the firft volatile phofphorus, which occafions all the danger of the operation. When thefe firft flalhes are over, increafe the heat of your matter by laying a large live coal upon the crucible. You will then fee the fecond phofphorus, like a luminous, fteady va¬ pour, of a colour inclining to violet, covering the whole fufface of the matter : It continues for a very long time, and diffiifes a fmell of garlick, which is the diftinguiftiing odour of the phofphorus you are feeking. “ When this luminous vapour is entirely gone, pour the red-hot matter out of the crucible upon an iron plate. If you do not find one drop of fait in fufion, but that, on the contrary, the whole falls readily into powder, it is a proof that your matter was fufficiently lixiviated, and that it contains no more fixed fait, or fea-falt, if you will, than is requifite. If you find on the plate a drop of fait coagulated, it fhews that there is too much left in it, and that there is danger of your mifcarrying in the operation ; becaufe the redundant fait would corrode and eat through the retort. In this cafe your matter muft be walhed again, and then fufficiently dried.” The furnace muft be fo conftrufted, that within a nar¬ row compafs it may give a heat at leaft equal to that of a glafs-houfe furnace, or rather greater, efpecialiy during the laft feven or eight hours of the operation. M. Hel¬ lot, in his Memoir, gives an exadt defcription of fuch a furnace. “ As certain accidents may happen in the courfeof the operation, fome precautions are to be taken again!! them. For inftance, if the ballon fticfuld break while the phof¬ phorus isdiftilling, and any of it Ihould fall on combufti- ble bodies, it would fet them on fire, and probably burn the laboratory, becaufe it is not to be diftinguiftied with¬ out the greateft difficulty. The furnace muft therefore be eredled under fome vault, or upon a bed of brick-work, raifed under fome-- chimney that draws well : Nor muft any furniture or utenfil of wood be left near it. If a little flaming phofphorus fhould fall on a man’s legs or hands, in lefs than three minutes it would burn its* way to the very bone. In fuch a cafe nothing but urine will flop its progrefs. s “ If the retort crack while the phofphorus is diftilling, 2 I there 126 C H E M there is an unfuceefsful end of your operation. It is eafy to perceive this by the ftink of garlick which you will fmell about the furnace; and moreover, the flame that ifliies through the apertures of the reverberatory will be of a beautiful violet colour. The; aeid of fea fait always gives this colour to the flame of fuch matters as are burnt along with it. But if the retort break be¬ fore the pholphorus hath made its appearance, its con¬ tents may be faved by throwing a number of cold bricks into the fire-place, and upon them a little water to quench the fire at once.” All thefe ufeful obfervations we owe alfo to M. Hellot. The phofphoms here defcribed was firft difcovered by' a citizen of Hamburg named Brandt, who worked upon urine in fearch of the philofopher’s ftone. Afterwards two other ikilful cliemifts, who knew nothing anore of the procefs than that phofphorus was obtained from urine, or in general from the human body, likewife endeavour¬ ed to. difcover it; and each of them feparately did adtu- ally make the difcovery. Thefe two chemifts were Kunckel and Boyle. The former perfeded the difcovery, and found out a method of making it in confiderable quantities at a time ; which obcafioned it to be called Kunckel's phofphorus. The other, who was an Englifh gentleman, had not time to bring his difcovery to perfection, and contented him- felf with lodging a voucher of his having difcovered it in the hands of the fecretary of the Royal Society of London, who gave him a certificate thereof. “ Though Brandt, who had befor?this fold his fecret to a chemill: named Krafft, fold it afterwards to feveral other perfofis, and even at a very low rate : and though Mr Boyle publdhed the procefs for making it; yet it is extremely probable that both of them kept in their own hands the mafter-key ; I mean, the particular marage- merit necefjary. to make the operation fucceed: For till Kunckel found it out, no other chemifl: ever made any confiderable quantity thereof, except Mr Godfrey Han- witz,: an EngHfii chemill, to whom Mr Boyle revealed the whole myflery. “ And thus it came to pafs, that, after Kuncke! and Boyle died. M Godfrey Hank wit z was the only chemill that could fupply Europe therewith ; on which account it is likewife very well known by the name of Englijh phofphorus Almofl all the chemifts confider phofphorus as a fub- fiance confifHng of the acid of fea fait combined with the J)hlogifton, in the fame manner as fulphur confifts of the vitriolic acid combined with the phlogifton. This opinion is founded on the following principles. Fir ft, urine abounds with fea-falr, and contains alfo a great deal of phlogifton : now thefe are the ingredients of which they conjecture phofporus to be compofed. Secondly, phofphorus has many of the properties of fulphur; fuch as being foluble in oils; melting with a gentle heat; being very corabuftible ; burning without any foot ; giving a vivid and bluifti flame; and laftly, leaving an acid liquor when burnt: fenfible proofs that it differs from fulphur in nothing but the nature of its acid. I S T R Y. Thirdly, this acid of phofphorus, being mixed with a folution of filver in fpirit of nitre, precipitates the filver; and this precipitate is a true lilna cornea, -Which appears to be more volatile even than the comrhon fort. This fact proves more inconteftably that the acid of phofpho¬ rus is of the fame nature with that of fea-falt. Fourthly, M. Stahl obferves, that if fea-falt be call on live coals, they inftantly burn with great adivity; that they emit a vivid flame, and are much fooner con¬ firmed . than if.none, of this fait had touched them; that fea-falt in fubftance, which will bear the violence of fire a confiderable time when fufed in a crucible, without fuftaining any fenfible diminution, yet evaporates very quickly, and is reduced to white flowers, by the im¬ mediate contad of burning coals; and laftly, that the flame which rifes on this occafion is of a blue colour in¬ clining to violet, efpecially if it be not thrown diredly on the coals themfeives, but kept in fufion amidft burn¬ ing coals, in a crucible fo placed that the vapour of the fait may join with the inflamed phlogifton as it riles from the coals. Thefe experiments of Mr Stahl’s prove, that the phlo¬ gifton ads upon the acid of fea-falt, even while it is com¬ bined with its alkaline bafts. The flame that appears on this occafion may be confidered as an imperfed phofpho¬ rus : and indeed its colour is exadly like that of phof¬ phorus. All the fads above related evince, that the acid of phofphorus is akin to that of fea-falt; or rather, that it is the very fame. But there other fads which prove, that this acid undergoes fome change at leaft, fome pe¬ culiar preparation, before it enters into the compofition of a true phofphorus ; and that, when extricated there¬ from by burning, it is not a pure acid of fea-falt, but is ftill adulterated with a mixture of fome other fubftance, which makes it confiderably different from that acid. For thefe obfervations we are obliged to M. Mafggraff. M. Marggraff hath alfo publilhed a procefs for ma¬ king phdfphorus, and allures us, that by means thereof we may obtain in lefs time, with lefs heat, lefs trouble, and Ids expence, a greater quantity of pholphorus than by any other method. His operation is this: He takes two pounds of fal ammoniac in powder, which he mixes accurately with four pounds of minium. This mixture he puts into a glafs retoi t, and with a gra¬ duated life draws off a very lharp, volatile, urinous fpirit. We obferved in Part I. that fome metallic fubftances have the property of decompofing fal ammoniac, and fe- paratfng its volatile alkali. Minium, which is a calx of lead, is one of thofe metallic fubftances. In this expe¬ riment it decompofes the fal ammoniac, and feparates its volatile alkali: what remains in the retort is a combi¬ nation of the minium with the acid of fal ammoniac, which is well known to be the fame with the marine acid.; and confequently the refidue of this operation is a fort of plumbum cbrneum. The quantity thereof is four pounds eight ounces. Of this he mixes three pounds with nine or ten pounds of urine, that has flood putrefying for two months, evapo¬ rated to the coafiftence of honey. Thefe he mixes by C H E M by little and little in an iron pan over the fire, ftirring the mixture from time to time. Then he adds half a pound of charcoal duft, and evaporates the matter, kept continually ftirring, till the whole be brought to a bkck powder. He next diffills the mixture in a glafs retort with degrees of fire, which he raifes towards the end fo as to make the retort red-hot, in order to expel all the urinous fpirit, fuperfluous oil, and ammoniacaT fait. The diftillation being tinifhed, there remains nothing. in ' the retort but a very friablevh/o? mortuum. This remainder he puiverifes again, and throws a pinch of it on live coals to difcover whether or no the matter be rightly prepared for yielding phofphorus. If it be’ fo, it prefently emits an arfenical odour, and a blue undulating flame, which pafles over the furface of the coals like a wave. Being thus aflured of the fuccefs of his operation, he puts one half of his matter, in three equal parts, into three fmall earthen German retorts, capable of holding about eighteen ounces of water a-piece Thqfe three retorts, none of which is above three quarters full, he places together in one reverberatory furnace, built much like thofe we have defcribed, except that it is fo eon-- ftrufted as to hold the three retorts difpoied in one line. To each retort he lutes a recipient fomething more than, half fnll of water, ordering the whole in fuch a manner, that the nofes of bis retorts almolt touch the furface of the water. He begins the diftillation with warming the retorts flowly, for about an hour, by a. gentle heat. When that time is eiapfed he raifes the fire gradually, fo that in half an hour more the coals begin to touch the bottoms of the retorts. He continues throwing coals into the furnace by little and little, till they rile half way the height of the retorts; and in this he employs another half hour. Laftly, in the next half hour he raifes the coals above the bowels of the retorts. Then the phofphorus begins to afcend in clouds: on this he inftamly increafes the heat of the fire as much as pdffible, filling the furface quite up with coals, and making the retorts very red. This degree of fire caufes the phofphorus to diftill in drops which fall to the bottom of the water. He keeps up this intenfe* heat for an hour and half, at the end of which the operation is finifh- ed; fo that it lafts but four hours and a half in all: In the fame manner he diftills the fecond moiety of his mixture in three other fuch retorts. He purifies and moulds his phofphorus much in the fame manner as M. Hellot does. From die quantity of ingredients above-mentioned, he obtains two ounces and a half fine cryftalline moulded phofphorus. The acid of phofphorus feems to be more fixed than any other: and therefore if you would feparate it by burning from the phlogifton with which it is united, there is no occafion for fuch an apparatus of veffels as is employed for obtaining the fpint of fulphur. For this acid will remain at the bottom of the veffel in which you burn your phofphrus: indeed, if it be. urged by the force of fire, its moft fubtile part evaporates, and the re¬ mainder .appears in the form of a vitrified matter. This acid effervefces with fixed and volatile alkalis. I S T R Y. 127 and therewith forms neutral falts; but very different from fea-falt, and from fal ammoniac. That which has a fixed alkali for its bafis does not crackle when thrown on burning coals; but fwells and vitrifies like borax. That which has a volatile alkali for its bafis fhoots into long pointed cryftals ; and, being urged by fire in a re¬ tort, lets go its volatile alkali, a vitrified matter re¬ maining behind. We fhall conclude this article with an account of cer¬ tain properties of phofporus which have not yet been mentioned. Phofphorus diffolves by lying expofed to the air. What water cannot effed, fays M..Hellot, or at leaft requires eight or ten years to bring about, the moifture of the air accomplifhes in ted or twelve days; whether it be that the phofphorus takes fire in the air, and the in¬ flammable part evaporating, almoft entirely, leaves the acid of the phofphorus naked, which like all other acids, when exceedingly concentrated, is very greedy of moi¬ fture; or elfe that the moifture of the air, being water divided into infinitely fine particles, is fo fubtile as to find its way through the pores of the phofphorus, into which the groffer partitles of common water can by no means infinuate themfelves. Phofphorus heated by the vicinity of fire, or by being any way rubbed, foon takes fire and burns fiercely. It is foluble in all oils, and in anher, giving to thofe liquors the property of appearing luminous, when the bottle conJ‘ taining the foktion is opened. Being boiled in water, it likewife communicates thereto this luminous quality. The late Mr Groffe obferved, that phofphorus being diffolved in eflential oils cryftallifes therein. Thefe cry¬ ftals take fire in the air, either when thrown into a dry velfel, or wrapt up in a piece of paper. If they be dip¬ ped in fpirit of wine, and taken out immediately, they do not afterwards take fire in the air : they fmoke a little, and for a very Ihort time, but hardly wafte at all. Though feme of them were left in a fpoon for a fort¬ night, they did not feem to have loft any thing of theif bulk : but when tl\e fpoon was warmed a little they took fire, juft like common phofphorus that had never been diffolved and cryftatlifed in an effential oil. M. Marggraff, having put a dram of phofphorus with an ounce of highly concentrated fpirit of nitre into a glafs retort, obferved, that, without the help of fire, the acid diffolved the phofphorus ; ‘that part of the acid came over into the recipient which Was luted to the retort; that at the fame time the phofphorus took fire, burnt furioufly, and burft the vcffds with- of this kind happens when any of the other acids, though con¬ centrated, are applied to phofphorus. TV decompofe Sea fait hy means of the Vitriolic Acid. Glauber's Salt. ‘The P ur if cation and Concentration of Spirit of Salt. Put the-fea-falt from which you mean to extraeft the acid into an unglaxed earthen pipkin, and fet it amidft live coals. The fait will decrepitate, grow dry, and fall into a powder. Put this decrepitated fait into a tubu¬ lated glafs retort, leaving two thirds thereof empty. Set the retort in a reverberating furnace ; apply a re¬ ceiver 128 C H E M ceiver like that iifed in difrilling the fmoking fpirit of nitre, and lute it on in the fame manner, or rather more exactly if poiTible. Then through the hole in the upper convexity of the retort pour a quantity of highly concen¬ trated oil of vitriol, equal in weight to about a third part of your fait, and immediately (hut the hole very clofe with a glafs (topple, fir(t rubbed therein with emery fo as to fit it exactly. As foon as the oil of vitriol touches the fait, the re¬ tort and receiver will be filled with abundance of white vapours ; and foon after, without lighting any fire in the furnace, drops.of a yellow liquor will diftill from the nofe of the retort. Let the diftillation proceed in this manner without fire, as long as you perceive any drops come ; afterwards kindle a very fmall fire under the re¬ tort, and continue diflilling and railing the fire by very flow degrees, and with great caution, to the end of the diftillation ; which will be finiflred before you have oc- cafion to make the retort red-hot. Unlute the veflels, and without delay pour the liquor, which is a very fmoking Ipirit of fait, out of the receiver into a cryftal Bottle, like that direfted for the fmoking fpirit of nitre. When the operation is finilhed, we find a white, fa- line mafs at the bottom of the retort as in a mould. If this mafs be difiblved in water, and the folution cryftal- lized, it yields a confiderable quantity of fea-falt that hath not been decompofed, and a neutral fait confiding of the vitriolic acid united with the alkaline bafis of that part which hath been decompofed. This neutral fait, which bears the name of Glauber its inventor, differs from vitriolated tartar, or the Sal de duobtts, w'hich remains after diftilling the nitrous acid, efpecially in that it is more fufible, more foluble in water, and hath its cryftals differently figured. But as in thefe two falts the acid is the fame, the differences that appear between them muft be attributed to the peculiar nature of the bafis of fea- falt. Spirit of fait drawn by the procefs above defcribed is tainted with a fmall mixture of the vitriolic acid, carried up by the force of fire before irlrad time to combine with the alkali of the fea-falt; which happens likewife to the nitrous acid procured in the fame manner. If you defire to have it pure, and abfolutejy free from the acid of vi¬ triol, it muft be diftilled a fecond time from fea-falt, as the acid of nitre was before dtredted to be diftilled again from frefh nitre, in order to purify it from any vitriolic taint. To dccompofe Sea-falt by means of the Nitrous Acid. Aqua regis. Quadrangular Nitre. Take dried fea-falt: bruife it to powder: put it in¬ to a glafs retort, leaving one half of the veflel empty. Pour upon it a third of its weight of good fpirit of nitre. Place your retort in the fand-bath of a reverberating fur¬ nace ; put on the dome ; lute to the retort a receiver having a fmall hole in it, and heat the veflels very flowly. There will come over into the receiver fome vapours, and an acid liquor. Licreafe the fire gradually till no¬ thing more rifes. Then unlute the veffels, and pour the liquor out of the receiver into a cryftal bottle, flopped like others containing acid fpirits. I S T R Y. The nitrous acid hath a greater affinity than the ma¬ rine acid with fixed alkalis. When therefore fpirit of nitre and fea-falt are mixed together, the fame confe- quences will follow as when the vitriolic acid is mixed with that fait; that is, the nitrous acid will, like the vitriolic, decompofe it, by diflodging its acid from its alkaline bafis, and affuming its place. But as the ni¬ trous acid is confiderably weaker, and much lighter, than the vitriolic acid, a good deal of it rifes along with the acid of fea-falt during the operation. The liquor found in the receiver is therefore a true aqua regis. If decrepitated fait, and a right fmoking fpirit of nitre, be employed in this procefs, the aqua regis obtained will be very ftrong. The operation being finifhed, there is left in the retort a faline mafs, containing fea-falt not decompofed, and a new fpecies of nitre, which having for its bafis the alkali of fea-falt, that is, an alkali of a peculiar nature, differs from the common nitre, i. In the figure of its cryftals ; which are folids of four ficfes, formed like lozenges : 2. In that it cryftallizes with more difficulty, retains more water in its cryftals, attra&s the moifture of the air, and diffolves in water with the fame circumftances. as fea fait, 0/ B O R A X. To dtcompofe Borax by the means of Acids, and to fe- parate from it the Sedative Salt by Sublimation and by Cryjlallifation. Reduce to a fine powder the borax from which you intend to extradl: the ledative fait. Put this powder into a wide-necked glafs retort. Pour upon it an eighth part of its weight of common water, to moiften the powder ; and then add concentrated oil of vitriol, to the weight of fomewhat more than a fourth part of the weight of the borax. Set the retort in a reverberatory, make a mode¬ rate fire at firft, and augment it gradually till the retort become red-hot. A little phlegm will firft come'over, and then, with the laft moifture that the heat expels, the fedative fait will rife; by which means fome of it will be diffolved in this laft phlegm, and pafs therewith into the receiver; but moft of it will adhere in the form of faline flowers to the fore-part of the neck of the retort, juft where it is clear of the groove of the furnace. There they colled! into a heap, which the fucceeding flowers pufti infenfibly for¬ ward till they (lightly (top the paffage. Thofe which rife after the neck is thus flopped flick to the after part of it which is hot, vitrify in fome meafure, and form a circle of fufed fait. In this ftate the flowers of the feda¬ tive fait feem to iffue out of the circle, as from their bafis : They appear like very thin, light, (hining fcales, * and muft be brufhed off with a feather. At the bottom of the retort will be left a faline mafs : Diffolve this in a fufficient quantity of hot water ; filter the folution, in order to free it from a brown earth which it depofites ; fet the liquor to evaporate, and cryftals of fedative fait will form in it. Though borax is of great ufe in many chemical ope¬ rations, efpecially in the fufion of metals, as we (hall hare C H E M I have occafion to fee, yet, till of late years, chemills were quite ignorant of its nature, as they (Hll are of its origin ; concerning Which we know nothing with certain¬ ty, but that it comes rough from the Ealt Indies, and is jnirified by the Dutch. Of Operations on Metals. Of Go L D. To feparats Gold, by Amalgamation and likewife diflblves at the fame time fome portion of the ore itfelf. With this folution of the ore of bifmuth Mr Hellot makes a very curious fympathetic ink differing from all that were known before. Mr Hellot prepares the liquor in the following man¬ ner : “ He bruifes the ore of bifmuth to a coarfe pow¬ der. On two ounces of this powder he pours a mixture of five ounces of common water with five ounces of aqua fortis. He does not heat the veffel till the firft ebullitions are over. He then fets^it in a gentle fand-heat, and lets it digeft there till he fees no more air-bubbles rife. When none appear in this heat, he increafes it fo as to make the folvent boil flightly for a full quarter of an hour. It takes up a tindhire nearly of the colour of brown beer. The ore that gives the aqua fcrtistti\% colour is the beft. He then lets the folution cool, laying the matras on its fide, that .hes-may decant the liquor more conveniently when all is precipitated that is not taken up by the fol¬ vent. I S T R Y. “ The fecond veffel, into which the liquor is firft de¬ canted, he alfo lays declining, that a new precipitation of the undiffolved matters may be obtained ; after which he pours the liquor into a third veffel. This liquor muft not be filtered, if you would have the reft of the procefs fucceed perfectly; becaufe the aqua fortis would diffolve fome of the paper, and that would fpoil the colour of your liquor. “ When this folution, which Mr Hellot calls the im¬ pregnation, is thoroughly clarified by being decanted three or four times, he,puts it into a glafs bafon with two ounces of very pure lea-fait. The fine white fait made by the fun fucceeded beft with Mr Hellot. If that cannot be had, common bay-falt purified by folution, filtration, and cryftallifation, may be ufed inftead of it. But as it is rare to meet with any of the fort that is not a little tainted wfith iron, the white bay fait is to be-preferred. The glafs bafon fle fets in a gentle fand-hear, and keeps it there till the mixture be reduced by evaporation to an almoft dry faline mafs. “ If you defire to fave the aqua regis, the impregna¬ tion muft be put into a retort, and diftilled with the gen¬ tle heat of a fand-bath. But there is an inconvenience, as Mr Hellot obferves, in employing a retort; which is, that, as the faline mafs cannot be ftirred while it coagu¬ lates in the retort, it is reduced to a compadt cake of coloured fait, which prefents but one Angle furface to the water in which it muft be, diffolved; fo that the dif- folution thereof takes up fometimes no lefs than five or fix days. In the bafon, on the contrary, the faline mafs is eafily brought to a granulated fait, by ftirring it with a glafs rod; and, when thus granulated, it has a great deal more furface ; it diflblves more eafily, and yields its ti'nbture toSjvater in four hours time. Indeed one is more expofed to the vapours of the folvent, which would, be dangerous, if the operation were to be often perform¬ ed, without proper precautions. “ When the bafon, or little veffel containing the mixture of the impregnation and fea fait, is heated, the liquor, which was of an orange-coloured red, becomes a crimfen red; and, when all the phlegm of the folvent is evaporated, it acquires a beautiful emerald colour. By degrees it •'thickens, and turns of the colour of a mafs of verdegris. It muft then be carefully ftirred with the glafs rod, in order to granulate the fait, which muft not be kept over the fire till it be perfeftly dry: becaufe you run a rifle of lofing irrecoverably the colour you are feeking. You may be fure you have loft it, if by too much heat the fait that was of a green colour turn to a dirty yellow. If it be once brought to this ftate, it will continue without changing when cold : but if care be ta¬ ken to remove it from the fire while it is ftill green, you will fee it gradually grow pale, and become of a beauti¬ ful rofe-coloui as it cools. “ Mr Hellot feparates it from this veffel, and throws it into another containing diftilled rain-water : and this fecond .veffel be keeps in gentle digeftion, till he obferves that the powder which falls to the bottom is perfetfly white. If, after three or four hours digefting, this powder ftill continues tinged with a rofe colour, it is a proof that water enough was not added to diffolve all the C H E M fait impregnated with the tinfture of the folution. In this cafe, the firfl tinged liquor mud be poured off, and frefh water added in proportion to the quantity of tinged fait that is fuppofed to remain mixed with the preci¬ pitate. “ When the ore is pure, and doth not contain a great deal of fufible done, commonly called flMor, or quartz, an ounce of it generally yields tinfture enough for eight or nine ounces of water, and the liquor is of a beautiful colour, like that of the lilach or pipe-tree bloffom. In order to prove the effedt of this tindture, you mud write with this lilach-coloured liquor on good well-gummed paper, that does not link : or you may ule it to lhade the leaves of fome tree or plant, having fird drawn the out¬ lines thereof lightly with China ink or with a black lead pencil. Let this coloured drawing, or writing, dry in a warm air. You will perceive no colour while it is cold; but, if it be gently warmed before the fire, you will fee the writing, or the drawing, gradually acquire a bjue or greenilh blue colour, which is vifible as long as the paper continues a little warm, and difappears entirely when it cpols.” ' ' The Angularity of this fympathetic inkponfids in its property of difappearing entirely, and becoming invifible, though it be not touched with any thing whatever : and this didinguilhes it from all others ; which, when once rendered vifible by the application of proper means, do not again difappear, or at lead not without touching the drokes on the paper with fome other liquor, 0/ Z I N C. To extraH Zinc from its Ore, or from Calamine. Take eight parts of calamine reduced to a powder; ' mix this powder accurately with one part of fine char¬ coal dud, previoufly calcined in ^ crucible to free it from all moidure : put this mixture into a done retort coated with lute, leaving a third part of it empty : fet your re¬ tort in a reverberatory furnace, capable of giving a very fierce heat.- To the retort apply a receiver, with a little water in it. Kindle the fire, and raife it by degrees till the heat be drong enough to melt copper. With this de¬ gree of fire the zinc being metallifed will feparate from the mixture, and fublime into the neck of the retort, in the form of metallic drops. Break the retort when it is cold, and colledt the zinc. Mod of the zinc we have comes from an ore of diffi¬ cult fufion that is worked at Goflar, and yields, at one and the fame time, lead, zinc, and another metallic matter called cadmia fornacum, which alfo contains much zinc. The furnace ufed for fmelting this ore is clofed on its fore-fide with thin plates or tables of done, not above an inch thick. This done is greyiffi, and bears a vio¬ lent fire. In this furnace the ore is melted amidd charcoal, by the help of bellows. Each melting takes twelve hours, during which time the zinc flowing with the lead is re- folved into flowers and vapours, great part of which ad¬ heres to the ddes of the furnace in the form of a very I s T R Y. 143, hard crud of earth. The workmen take care to remove this crud from time to time ; for it would otherwife grow fo thick at lad, as to leffen the cavity of the furnace very confiderably. There’adheres moreover to the fore-part of the fur¬ nace, which is formed, as we faid before, of thin plates of done, a metallic matter, which is the zinc, and is carefully collected at the end of each melting, by re¬ moving from this part all the live coals. A quantity of fmall coal is laid unlighted at the bottom ; and on this fmall-coal, by driking the done-plates gently with a ham¬ mer, the zinc is made to fall out of the other matter, known by the Latin name of cadmia fornacum, among which it appears fixed in a radiated form. To this other matter we may properly enough givethe name of furnace- calamine. The zinc fall? in the form of a melted metal, all on fire, and in a bright flame. It would foon be en¬ tirely burnt and reduced to flowrers, if it were not extin- guiflied, and eafily cooled and fixed, by being hid under the ifnlighted fmall-coal placed below on purpofe to re¬ ceive it. The zinc adheres to the fore-pact of the furnape pre¬ ferably to any other, becaufe that being the thinned, is therefore the cooled : and, in order further to promote its fixing on this part, they take care to keep the thin done-plates cool during the operation, by throwing wa¬ ter on. them. Hence it appears that zinc is not extra&ed from its ore by fufion'vknd the precipitation of a regulus, like other metallic fubdances. This is owing to the great volati¬ lity of our femi-metal, which cannot, without fubliming, bear the degree of fire neceffary to melt its ore. It is at the fame time fo combudible, that a great part of it rifes, in flowers which have not the metalline form. To fublime Zinc into Planners. Take averydeefi, large crucible : place this crucible in a furnace, To that it may dand inclining in an angle of forty-five degrees nearly. Throw fome zinc into it, and kindle a fire in the furnace fomewhat dronger than wduld be neceffary to keep lead in fufion.. The zinc will melt.. Stir it with an iron wire, and there will appear on its fur- face a very bright white flame : two inches above this flame a thick fmoke will be formed, and with this fmoke exceeding white flowers will rife, and remain fome timp adhering to the fides of the crucible, in the form of a very fine light down. When the flame dackens, dir your melted matter again with the iron wire: you will fee the flame renewed, and the flowers begin again to appear in greater abundance. Go on thus till you obferve that the matter will not flame, nor any more flowers rife. To combine Zinc •with Copper. Brafs. Prince's Me¬ tal, See. Pound one part and an half of calamine, and an e- qual quantity of charcoal: mingle thefe two powders to¬ gether, and moiden them with a little water. Put this- mixture into a large crucible, or fome other earthen vef- fel that will bear a melting beat. Amongd and over this mixture put one part of very pure copper in thin plates, and then put frelh charcoal-dud over all: clofe the. 144 , C H E M 1 the crucible ; Tet it in a melting furnace ; put coals all. round it, and let them kindle gradually. Raife-the fire fo as to make the crucible very red-hot. When you ob- ferve' that the flame hath acquired a purple or blueilh- green colour, uncover the crucible, and dip into it an iron wire, to examine whether or no the copper be in fufion under the charcoal-dufl. If you find it is, mo¬ derate the force of the fire a little, and let your crucible remain in the furnace for a few minutes. Then take it out and let it cool: you will find your copper of a gold Colour,, increafed in weight a fourth, or perhaps a third part, and yet very malleable. The lapis calaminaris is not the only fubflance with which copper may be converted into brafs : all other Ores containing zinc, the furnace-calamine that fublimes where fuch ores are worked, tutty, zinc in fubftance, may be fubftituted for it, and, like it, will’ make very fine brafs ; but, in order to fucceed, fundry precautions are neceffary. This procefs is a fort of cementation ; for the calamine doth not melt; only the zinc is converted into vapours, and then combines with the copper. On this the fuccels of the operation partly depends, as it is the means of the cqpper’s preferving its purity and malleability; becaufe the other metallic fubftances that may be united.with the ore of zinc, or with the zinc itfelf, not having the fame volatility, cannot be reduced to vapours. If you are ap- prifed that the calamine, or other ore of zinc ufed on this occafion, is contaminated with a mixture of any o- ther metallic matter, you mull mingle luting earth with the charcoal-duft and the matter containing the zinc ; make it into a fliff pa/te with water ; of this make a bed at the bottom of your crucible, and ram it hard down; lay the copper-plates thereon, cover them with charcoal- dull, and then proceed as before. By this means, when the copper melts, it cannot fall to the bottom of the cru¬ cible, nor mix with the ore ; but is borne up by the mix¬ ture, and cannot combine with any thing but the zinc, that rifes in vapours, and, palling through the lute, fixes in the copper. Lapis Calaminaris, or other ore of zinc, may be alfo purified before it be ufed for making brafs; efpecially if adulterated with lead ore, which is often the cafe. For this purpofe the ore mult he foalted in a fire ftrong e- npugh to give a fmall degree of fufion to the leaden mat¬ terwhich will thereby be reduced into larger, heavier, and tougher maffes. The molt fubtile particles are dif- fipated in the torrefatfion, together with fome of the ca¬ lamine. The calamine, on the contrary, is by roafting made more tender, lighter, and much more friable. When it is in this condition, put it into a walking tray or fas ; dip the tray in a velfel full of water, and bruife the mat¬ ter it contains. The water will carry off the lightelt powder, which is the calamine, and leave nothing at the bottom of the tray but the heavielt fubltance; that is, the leaden matter, which is to be reje&ed as ufelefs. The powder of the calamine will fettle at the bottom of the velfel, where, after pouring off the water, it may be found, and ufed as above directed. In this operation the charcoal-duft ferves to prevent' ■both the copper and the zinc from being calcined : and : S T R Y. for this reafon, when you work on a great quantity of materials at once, it is not neceflary to ufe fo much charcoal dull, in proportion, as when you work but on a fmall quantity ; becaufe, the greater the mafs of metaC the lefs eafily will it calcine. Though the copper melts in this operation, yet it is far from being neceflary to apply fuch a llrong fire as copper ufually requires to melt it: for the accellion of the zinc, on this occalion, communicates to it a great de¬ gree of fuAbility. The increafe of its weight is alfo owing to the quantity of zinc combined with it. Cop¬ per acquires (till another advantage by its aflbeiation with this femi-metal; for it remains longer in the fire without calcining. Brafs well prepared ought to be malleable when cold. But in whatever manner it be made, and whatever pro¬ portion of zinc there be in it, it is conftantly found quite unmalleable when red-hot. Brafs melted in a crucible, with a fierce heat, takes fire almoft like zinc, and from its furface many white flowers afeend, dancing about in flakes like the flowers' of zinc. They are indeed the flpwers of zinc, and the flame of brafs urged by a ftrong fire is no other than the flame of the zinc that is united with the copper, and then burns. If brafs be thus kept long in fufion, it will lofe almoft all the zinc it contains. It will alfo lofe much of its weight, and its colour will be nearly that of cop¬ per. It is therefore necelfary, towards performing this operation aright, to feize the moment when the copper is fufficiently impregnated with zinc, when it hath ac¬ quired the moft weight and the fineft colour, with the leaft detriment to its duout a very prafticable method o£ doing it. The zinc muft be melted in a crucible, and ftirred briildy with a ftron^ iron wire, while tallow and mineral fulphur are alter¬ nately projefted upon it; but fo that the quantity of fulphur may greatly exceed that of the tallow. If the fulphur do not burn entirely away, but form a kind of fcoria on the furface of* the zinc, it is a fign that your femi-metal contains lead. In this cafe you muft continqe throwing in more fulphur; and keep ftirrmg the zinc in- celfantly, till you perceive that the fuiphur ceafes to u- nite any more with a metallic fubftance, but burns free¬ ly on the furface of the zinc. The femi-metal is then refined; becaufe the fulphur, which cannot diffolve it, unites very readily with the lead, or other metallic fub¬ ftance, contained in it If zinc thus refined be mixed with pure copper, in the proportion of a fourth or a third part, and the mixture be kep in fufion andconftantly ftirringforfome time, the brafs produced will be as duftile, when cold, as that made by cementation with the hpis calaminaris. With regard to prince’s metal, and other imitations of gold, they are made either with copper or brafs re¬ combined with more zinc. As it is neceffary. for gi¬ ving them a fine golden colour, to mix with them other proportions of zinc than that required to make brafs on- , ly, they are generally much lefs dudtile. Zinc dijfolved in the Mineral Acids. . Weaken concentrated oil of vitriol by mixing with it ah equal quantity of water. Into a matras put the zinc you intend to diffolve, firft broken- to fmall pieces. Pour on it fix times its weight of the vitriolic acid, low¬ ered as above dire died, and fet the matras in a fand-bath gently heated. The zinc will diflblve entirely, without any fediment. The neutral metallic fait refulting from this difiblution Ihoots into cryftals, which go by the name ot ■'white vitriol, or vitriol of zinc. . Zinc is diffolved by the nitrous and marine acids, much in the fame manner as by the vitriolic ; except that the marine acid does not touch a black, fpungy, rarefied matter, which it feparates from the zinc. M. Heliot found ilpon trial that this matter is not jnercury, and that it cannot be reduced to a metallic fubftance. A folution of zinc in the marine acid, being diftilled to drynefs, yields a fublimate on applying a violent heat to it. All the acids diflblve with eafe ; not only zinc, but its flowers alfo; and that nearly in the fame quantity, and .with almoft all the fame phenomena. Of Arsenic. To extra ft Arfenic from its Matrices. Zaffre or Smalt. Powder fome cobalt, white pyrites, or other arfeni- cal matters. Put this powder into a retort with a fliort wide neck, leaving a full third thereof empty. Set your retort in a reverberating furnace; lute on a receiver; heat your veflel by degrees, and increafe the fire till you fee a powder fublime into the neck of the retort. Keep up the fire in this degree as long as the fublimation continueswhen this begins to flacken, raife your fire, - Vol. II. No. 36.’ 3 I S T R Y. 145 and make it as ftrong. as the veflels will bear. When nothing more afcends," let it go out. On unluting the velfels, you will find in the receiver a little arfenic in the form of a fine light farina. The neck of the retort will be full of white flowers, not quite fo fine, fome of which will appear like little cryftals ; and if a good deal of arfenic be fublimed, a ponderous’matter, like a white, femi tranfparent glafs, will be found adhering to that part of the neck of the retort whiah is next its body. When all the arfenic the cobalt will yield is thus fe- parated, the earthy fixed matter left behind is mixed with divers fufible matters and vitrified, and produces a glafs of beautiful blue colour. It is calledThis glafs is to be prepared in the following manner. Take four parts of fine fufible fand, an equal quantity of any fixed alkali perfectly depurated, and one part of cobalt from which the arfenic hath been fublimed by tor- rcfaftion. Pulveriie thefe different fubftances very finely, and mix them thoroughly together; put the mixture in¬ to a good crucible, cover it, and fet it in a melting furnace. Make a ftrong fire, and keep it up conftantly in the fame degree for fome hours. Then dip an iron wire into the crucible; to the end of which a glaffy matter will ftick, in the form of threads, if the fufibn and vitrification be perfect. In this cafe take the crucible out of the fire; cool it by throwing water on it, and then break it. You will find in it a glafs, which will be of an exceeding deep blue, and almoft black, if the operation hath fuc- ceeded. This glafs, when reduced to a fine powder, ac¬ quires a much brighter and more lively blue colour. If you find after the operation that the glafs hath too little colour, the fufion muft be repeated a fecond time, with twice or thrice the quantity of cobalt. If, on the contrary, the glafs be too dark, lefs cobalt muft be- ufed. In order to make the effayof a particular cobalt, with a view to know wha!t quantity of blue glafs it will yield, it is not neceffary to perform the operation in the manner here fet down ; a great deal of time and trouble may be faved by melting one part of cobalt with two or three parts of borax. This fait is very fufible, and turnsj when melted, into a fubftance which, for a time, poffef- fes all the properties Of glafs. In this trial the glafs of borax will be nearly of the fame colour as the true glafs, or fmalt, made with the fame cobalt; The ores of bifmuth, as well as cobalt, yield a mat¬ ter that colours glafs blue; nay, the fmalt made with thofe ores is more beautiful than that procured from the ore of'pure arfenic. Some cobalts yield both arfenic and bifmuth. When fuch cobalts are ufed, ft is common to find at the bottom of the crucible a little button of metallic matter, which is called regulus of cobalt. This rega¬ ins is a fort of bifmuth, generally adulterated with a mixture of ferruginous and arfenical parts. The heavieft and moft fixed flowers of arfenic, procu¬ red from cobalt, have likewife the property of giving a blue colour to glafs. But this colour is faint : it is ow¬ ing to a portion of the colouring matter carried up along with the arfenic. Thefe flowers may be made an ingre¬ dient in the compofition of blue glafs, not only becaufe of the colouring principle they contain, but alfo becaufe 2 O they 146 C H E M they greatly promote fufion; arfenic being one of the moft efficacious fluxes known. In ffiort, all thofe blue glafles, or fmalts, contain a certain quantity of arfenic ; for a portion of this femi- metal always remains united with the fixed matter of the cobalt, though roafted for a long time, and in a very hot fire. The portion of arfenic that is thus fixed vitri¬ fies with the colouring matter, and enters into the cotn- pofition of the fmalt. The blue glafs made with the fixed part of cobalt hath feveral names, according to the condition in which it is. When it hath undergone the firft imperfedt degree of fufion only, it is called zaffre. It takes the name of fmalt when perfectly vitrified: and this again being pul- verifed is called psauder blue ; or, if finely levigated, blue enamel •, becaufe it is ufed in enamelling, as well as in painting earthen ware and porcelain. To feparate Arfenic from Sulphur. Powe-er the yellow or red arfenic which you intend to feparate from its fulphur. Moiften this powder with a fixed alkali refolved into a liquor. Dry the mixture gently; put it into a very tall glafs cucurbit, and fit on a blind-head. Set this cucurbit in a fand-bath; warm the veflels gently, and increafe the fire by degrees, till you perceive that no more arfenic fublimes. The arfe- uic, which before was yellow and red, riftfs into the head partly on white flowers, and partly in a compaft, white, femi-tranfparent matter, which looks as if it were vitrified. The fulphur combined with the fixed alkali remains at the bottom of the cucurbit. To give Arfenic the Metalline Form. Regulus of Ar¬ fenic. Take two parts of white arfenic in fine powder, one part of the black flux, half a part of borax, and as much clean iron filings. Rub the whole together, in order to mix them thoroughly. Put this mixture into a good cru¬ cible, and over it put fea-falt three fingers thick. Co¬ ver the crucible ; fet it in a melting furnace ; and begin ■with a gentle fire to heat the crucible equally. When arfenical vapours begin to afcend from the cru¬ cible, raife the fire immediately fo as to melt the mix¬ ture. Examine whether or no the,matter .be thoroughly melted, by introducing an iron wire into the crucible ; and if the fufion be perfedt, take the crucible out of the furnace. Let it cool; break it; and you will find in it a regulus of a white and livid metallic colour, very brittle, fcarcely. hard, but rather friable. To difil the Nitrous Acid bp the Interpoftion of Arfe¬ nic. 2?iW Aqua Fortis. Pulverise finely any quantity you pleafe of refined falt-petre. Mix it accurately with an equal weight of white cryltalline arfenic well pulverifed, or-elfe with very white and very fine flowers of arfenic. Put this mixture into a glafs retort, leaving one half of it empty. Set vc^ir retort in a reverberating furnace ; apply a receiver, having a fmall hole'drilled in it, and containing a little I S T R Y. filtered rain-water; lute the receiver to the retort with ftiff lute. Begin with putting two or three fmall live coals in the affi-hole of the furnace, and replace them with others when they are ready to go out. Go on thus warming your veflels by infenfible degrees, and put no. coals in the fire-place, till the retort begin to be very warm. You will foon fee the receiver filled with vapours of a dark red, inclining to a ruflet colour. With a bit of lute flop the little hole of the receiver. The vapours will be condenfed in the water of this veflel, and give it a very fine blue colour, that will grow deeper and deep¬ er aS the diftillation advances. If your falt-petre was not very dry, fome drops of acid will alfo come over, and falling from the nofe of the retort mix with the wa¬ ter in the receiver. Continue your diflillation, increa- fing the fire little by little as it advances, but ex¬ ceeding flowly, till you fee that when the retort is red-hot nothing more comes off; and then let your vef- fels cool. When the veffels are cold, unlute the receiver, and as expeditioufly as you can pour the blue aqua fort is it con¬ tains into a cryftal bottle", which you .mull feal hermeti¬ cally, becaufe this colour difappears in a Ihort time when the liquor takes air. You will find in the retort a white faline mafs moulded in its bottom, and fome flowers of arfenic fublimed to its upper cavity, and into its neck. Pulverife the faline mafs, and diffolve it in warm wa¬ ter. Filter the folution, in order to feparate fome arfe¬ nical parts that will be left on the filter. Let the filter¬ ed liquor evaporate of itfelf in the open air ; when it is fufficiently evaporated, cryftals will ffioot in it reprefent- ing quadrangular prifms terminated at each extremity by pyramids that are alfq quadrangular. Thefe cryftals will . be in confufed heaps at the bottom of the veffel : Over them will be other cryftkls in the form of needles; a fa¬ line vegetation creeping along the fides of the veffel; and the furface of the liquor will be obfeured by a thin dufty pellicle. To alkalifate Nitre by Arfenic. Melt in a crucible the nitre you intend to alkalifate. When it is melted, and moderately red, projedt upon it two or three pinches of pulverifed arfenic. A confider- able effervefcence and ebullition will immediately be pro¬ duced in the Crucible, attended with a noife like that which nitre makes when it detonates with an inflammable matter. At the fame time a thick fmoke will rife, which at firft will fmell like garlick, the odour peculiar to arfe¬ nic ; it will alfo fmell afterwards like fpirit of nitre. Wrhen the effervefcence in the crucible is over, throw again upon the nitre as much pulverifed arfenic as you did the firft time ; and all the fame phenomena will be repeated. Continue thus throwing in arfenic in fmall parcels, till it produce no more effervefcence; taking cafe to ftir the matter at every projection with an iron wire, the better to mix the whole together. Then increafe your fire, and melt what remains. Keep it thus in fufion for a quarter of an hour, and then take the crucible out of the fire. It will contain a nitre al- kalifed by arfenic. C H E M Of Vegetables. Of the S>ulfiances obtained from Vegetables by Exjprefiion only. To exprefs and depurate the Juice of a Plant, contain¬ ing its EJfential Salt. The Cryfiallifation of that Salt. Before fun-rife, gather a good quantity of the plant, from which you defign to exprefs the juice, in order to obtain its fait. Wafh it well in running water, to clear it of earth, infers, and other adventitious matters. Bruife it in a marble mortar; put it into a bag of new, ftrong, thick linen cloth; tie the bag tight, and com¬ mit it to a prefs. By preffing it ftrongly you will fqueeze out a great quantity of green, thick juice, which will have the fame tafte as the nlant. Dilute this juice with fix times as much pure rain water, and filter it repeated¬ ly through a woolen bag, till it pafs clear and limpid. Evaporate the filtered juice with a gentle heat, till it be almofl: as thick as before it was mixed with water. Put this infpiflated juice into a jar, or other veffel of earth or glafs; on its furface pour olive oil to the depth of a line, and fet it in a cellar. Seven or eight months after this pour off gently the liquor contained in the veffel, the infide of which you will find covered with a cryftallifed fait. Separate the cryftals gently; wafh them quickly with a little fair cold water, and dry them: this is the eflential oil of the plant. Every plant is not equally difpofed to yield its elfen- tial fait by the method here propofed. Succulent vege¬ tables only, whofe juices are aqueous and not too vif- cous, are fit for this purpofe. Such, for example, as forrel, brook-lime, fuccory, fumitory, water-crefles, plantain, , Mix thoroughly three or four pounds, of any fat oil whatever with twice its weight of lime flaked m the air. Put this mixture into a large earthen retort, leaving a third par-t of it empty. Set it in a reverberating furnace, and lute- on a receiver. Heat the veffel with a very gentle fire. A little flame will rife firft, and will foon be followed by an oil that will fall in drops from the nofe of the retort. Continue the diftill'ation very flowly, till you perceive the oil that comes over begin to be not quife fo fluid as before, but rather a little thicker. Then unlute your receiver, and put another in its place. Continue the diftillatidn, increafing your fire by degrees. The oil that comes over will grow thicker and thicker, its fluidity will decreafe, and it will acquire a dark-brown colour, which at laft will become blackifli. The oil will then be very thick. Pufh the operation till nothing more will come off, though the retort be red- hot. During the whole time this diftillation lafts, there ,.rifes a good deal of water in company with the oil. Keep the fecond thick oil by itfelf. • Mix the oil that came over firfl: in this operation with an equal part of frefti lime flaked in the air. Put the mixture into an earthen or glafs retort, of a fize fo pro¬ portioned to the quantity, that a third part thereof may remain empty. Diftill'as before. The fame phenomena will appear : a clear oil will firfl: come over, and be fuc- ceeded by one a little thicker. Then fhift your receiver, and diftill off all the reft of the oil with an increafed fire. The firft oil obtained by this fecond diftillation will be clearer and thinner than that of the firft diftillation ; and the fecond oil will riot be fo thick nor of fo deep a colour as before. Diftill over again in the fame manner the thin oil of this fecond diftillation, and go on thus repeatedly di- ftilling, till the firft clear oil come over with a degree of heat not exceeding that of boiling water. Then, inftead of mixing your oil with lime, put it with fome water in¬ to a glafs retort, or into a body with its head fitted on, and diftill it, keeping the water juft in a fimmer. Your Vox.. II. No. 36. 3 : S T R Y. 149 oil will be more and more attenuated, and, after being thus diftilled twice or thrice with water, will be fo lim¬ pid, fo thin, andfo clear, that you will fcarce be able to diftinguilh it from water itfelf. To combine Fat Oils with Acids. Put any fat oil whatevqr into a glafs bafon, and fet it in a fand-bath very moderately heated. Pour on this oil an equal quantity of concentrated oil of vitriol, which will immediately diffolve it with-violence ; a confiderable ebullition and effervefcence will arife, attended with great heat, and a prodigious quantity of black thick vapours, in which may be eafily perceived the fmell of burnt oil, together with that of a fulphureous acid. The mixture will become of a deep-red, black, and thick. Stir it with a fmall flick, till you obferve that all is quiet. To combine Fat Oils with Fixed Alkalis. Hard and Soft Soap. The DecOmpoftion of Soap. Take a lixivium of Alicant kelp made morecauftic by lime, as we ftiall fhew when we come to fpeak of alkalis. Evaporate this lye till it be capable of bearing a new-laid egg. Divide it into two parts ; and to one of thefe put juft water enough to weaken it fo that a new laid egg will not fwim in it, but fall to the bottom. With the lye thus weakened, mix an equal quantity of frefh-drawn olive oil. Stir and agitate the mixture well till it be¬ come very white. Set it over a gentle fire, and continue ftirring it inceffantly, that the two ingredients of which it is compounded may gradually combine together, as part of the water evaporates. When you perceive they begin to unite, pour into the mixture thrice .as much of the firft ftrong lye as-you took of olive oil. Continue the codlion with a gentle fire, always ftirring the matter, till. it become fo thick that a drop of it fixes, as it cools, in¬ to the confiftence that foap ought to have. By diffolving a little -of this foap in water, you will difcover whether or no it contains more oil than ought to be in the com- pofition. If it diffolve therein wholly and perfedtly,, without the appearance of the leaft little drop of oil float¬ ing on the water, it is a fign that it doth not-contain too much oil. If, on the contrary, you perceive any of thefe little globules, you muft pour into the veffel con¬ taining your matter a little more of the ftrong lye, to abforb the redundant oil. If there be too much of the alkali, it may be difcovered by the tafte. If the foap leave on your tongue the fenfatiqn of an alkaline fait, and produce an urinous favour, it is a fign that there is too much fait in proportion to the oil. In this cafe a lit¬ tle oil muft be added to the mixture, to faturate .the fu- perabundant alkali. An excefs in the quantity of alkali difcovers itfelf likewife by the foap’s growing moift in the air, on being expofed to it for fome time. Fixed alkalis, even when refolved into a liquor, that is, when loaded with much water, unite eafily with fat oils, as appears from the experiment juft recited, and re¬ quire but a moderate heat to perfedt that union. This combination may even be completely effedted without the aid of fire, and by the heat of the fun only, provided fufficient time be allowed for that purpofe. It only re¬ quires the mixture of the oil and alkali to be kept-five or 2 P fix 150 C H E M fix days in digeftion, and ftirred from time to time. A lixivium of pure alkali, not acuated by lime, m^y alfo be ufed to make foap : but it is obferved, that the combina¬ tion fucceeds better, and that the alkali unites fooner and more perfectly with the oil, when it is fharpened by lime. The oil is firft mixed with a weaker and more aqueous lye, to the end that the combination may not take place too haftily, but that all the particles of the two' fub- ftances to be compounded together may unite equally. But as foon as the alkali begins to diflblve the oil gra¬ dually and quietly, the diffolution may then be accele¬ rated ; and that is done by adding the remaining lye, which is ftronger and lefs diluted than the other. Soap made with olive oil is white, hard, and hath not a very difagreeable fmell : but as that oil is dear, others, even the fat and oils of animals, are fometimes fubfti- tuted for it. The foaps made with moft of thefe other matters are neither fo hard, nor fo white, as that made of olive oil : they are called foft foaps. Oils thus aflbciated with fixed alkalis are by that means rendered foluble in water ; becaufe the alkaline falts, having a great affinity with water, communicate part thereof to the oils with which they are now incor¬ porated. Yet the oil is not for all that rendered tho¬ roughly mifcible with water, or perfedtly foluble therein ; for the water in which foap is diflblved hath always a milky call: now there is no other criterion of a perfeft folution but tranfparency. Alkalis alfo lofe part of their affinity with water, by the union they thus contraA with oils : for, when the combination is properly made, they no longer attraft the moifture of the air, nor doth water diffiolve them in fuch quantities as before. The compofition of foap is plainly a faturation of an alkali with an oil ; and, in order to make perfect foap, we are forced, as was faid in the pro- cels, to grope, in a manner, by repeated trials, for this point of faturation ; juft as when we prepare A neutral fait by faturating an alkali with an acid. The union which the oil contradls with the alkali makes it lofe, in part, the readinefs with which it naturally takes fire ; becaufe the fait is not inflammable : the water alfo, which enters, in pretty cdnfiderable quantities, into the compofition of foap, contributes a good deal to hinder the accenfion of the oil. Soap may be decompounded either by diftilling it, or by mixing it with fome fubftance that hath a greater affi¬ nity than oil with alkalis. If we decompound it by diftillation, a phlegm, or tranfparent fpirit, of a fomewhat yellowilh colour, firft comes over. This liquor is the aqueous part of the foap, quickened by a little of its alkali, which gives it an acrid tafte. It is followed by a red oil, which at firft is pretty thin and limpid, but thickens as the diftillation advances, grows black, and has a very difagreeable empyreumatic . fmell. This oil is foluble in fpirit of wine. When the diftillation is finilhed, that is, when the retort being kept red-hot for fome time will difcharge no more, there is left in it a faline mafs ; which is the al¬ kali of the foap, crufted over with fome of the moft fixed parts of the oil, that are charred to a coal,. This lalt I S T II Y. may be reftored to the fame degree of purity it had before its combination with the oil, by calcining it in a crucible with a naked fire, that may confume this burnt part of the oil, and reduce it to alhes. It is plain, that the oil contained in foap is afFedled.by diftillation, much in the fame manner as that which we mixed with lime and diftilled. Mr Geoffroy, by analyfing foap with care, difcovered that two ounces thereof contain ninety-fix grains of fait of kelp, freed from all oil and moifture ; or two drams and forty-eight grains of that fait, as it is ufed in manu- fa&uring foap ; that is, containing water enough to make it cryftallife ; one ounce three drams twenty grains of o- live oil; and about two drams four grains of water. As acids have a greater affinity chan any other fub¬ ftance with alkalis, they may be very effedually employed to decompound foap. If you propofe to decompound foap by means thereof, you muft firft diflblve it in a fufficient quantity of water. Mr Geoffroy, who made this experiment likewife, dif- folved two ounces thereof in about three gallons of warm water, and to the folution added oil of vitriol, which he let fall into it drop by drop. Every time a drop of acid falls into it, a coagulum is formed in the liquor. The vefiel in which the folution is contained muft then Be Ihaken, that the acid may equally attack all the alkali diffufed in it When no new coagulation is produced by a drop of the acid, it is a fign you have added e- nough. The liquor then begins to grow clear: and if another quart of water be added, in order to facilitate the feparation of the oily particles, you will fee them rife and unite together on the furface of the liquor. This is a pure, clear, true olive oil, hath its tafte* its fmell, and, like it, is fluid in warm weather, and be¬ comes fixed by cold. Yet it differs in fome refpedls from that which never hath been united with an alkali in order to form a foap; for it burns more vividly and more rapidly, and is folut>Ie in fpirit of wine. We ihall account for thefe differences when we come to treat of ardent fpirits. Not only the vitriolic acid, but all others, even thofe obtained from vegetables, are capable of decompounding, foap, and feparating the oil from the alkali. In the li¬ quor wherein foap is thus decompounded, is found a neu¬ tral fait, confifting of the acid made ufe of, united with the alkali of the foap. If’the vitriolic acid be ufed, you will have a Glauber’s fait; a quadrangular nitre, if the nitrous acid be ufed ; and fo of the reft. The facility With which, acids decompound foap is the reafon that no water, but what is very pure, will diflblve it, or is fit to be ufed in waffling with it. Water that doth not diflblve foap well is ufually called hard water. Such waters contain a certain quantity of faline matters, waffled out of the earths through which they pafs. The hardnefs of water is generally occa- fioned by felenitic particles.. The hardtrefs of moft well-waters is owing to a confi- derable quantity of felenitic gypfum with which the foil abounds. The felenites are neutral falts confifting. of the vitriolic acid united with an earthy bafis. If, therefore* foap be put into water in which a lak of this kind is dif- iblved*. CHE M folved, it is evident that the vitriolic acid in the felenites, having a greater affinity with the fixed alkali of the foap than with its own earthy balls, will quit the latter to u- nite with the former ; and thus the foap will be decom¬ pounded inftead of being difiblved. Accordingly we fee, that, when we attempt to difiblve foap in our well-water, the furface of the liquor is ip a fhort time covered with a fat oily pellicle. However, this decompofition of foap is not complete ; at leaft but a fmall part of it is per- fedtly decompounded ; becaufe the great quantity of fe¬ lenites, with which the water is impregnated, hinders the foap from mixing fo thoroughly with it, as is requi- fite to produce a total decompofition thereof. All mineral waters are likewife hard, with regard to foap ; for, as mod; of them owe their virtues to the efflo- refcencies they have walhed off, from pyrites that have grown hot and begun to be decompofed, they are im¬ pregnated w^th the faline matters produced by pyrites in that date ; that is, with aluminousj vitriolic, and ful- phureous fubdances, which have the fame effect on foap "as the felenites hath. Mineral waters containing neutral falts only, fuch as fea-falt, Epfom fait, Glauber’s fait, are neverthelefs hard with regard to foap, though the acids of thofe falts, being united with fixed alkalis, are incapable of decom¬ pounding it. The reafon is, that thofe neutral fails are more foluble in water than foap is ; fo much indeed as even to exclude it: becaufe each of the two principles that compofe them hath a very great affinity with water; ■whereas only one of the principles of foap, namely, its alkali, hath that affinity ; the other, viz. the oily prin¬ ciple, having none at all. Thus water impregnated with an acid, or with any neutral fait, is hard with regard to foap, and incapable of diffolving it; and hence it fol¬ lows, that foap is a fort of touchdone for trying the pu¬ rity, of water. Wine diffolves foap ; but imperfedly, becaufe it con¬ tains an acid or tattarous part. Spirit of wine alfo dif¬ folves it: but neither is this diffolution perfedt; becaufe it contains too little water : for its fpirituous part can diffblve nothing but the oil,of the foap ; and the alkali is not at all, or at lead in a very fmall quantity, foluble in this mendruum. The true folvent of fopp is therefore a liquor that is partly fpirituous, partly aqueous', and not acid. Brandy has thefe qualities : and accordingly it is the folvent that unites bed with foap, diflblves the greated quantity,, and makes the mod limpid folution thereof. Yet even this folution hath fomething of a milky cad, occafioned by its not being entirely free from, an acid, or the tartarous principle. This fault may be eafily cor- redted, by mixing with it a little alkali to abforb the acid. A dram of crydallifed fait of kelp mixed with three ounces and a half of good brandy, renders it ca¬ pable of diffolving an,ounce and two drams of good hard ibap into a perfectly limpid liquor. Some years ago it was difcovered that foap might be ufed with great fuccefs in medicine, and that it poffefles the property of diffolving the' dony concretions that form in feveral parts of the body, particularly in the kidneys I S T R Y. I5i and bladder Soap is the bafis of the compofition known by the name of Mrs Stephen's remedy ; and in this one ingredient its whole virtue refides. From what hath been faid on the nature of this com¬ pound, as well as on the caufe and phenomena of its dif¬ folution, it plainly appears to be of the lad confequence, in adminidering it to a patient, that his conditution be confidered, and a proper regimen ordered. All acids diould be abfolutely forbid him; as we know they hinder the foap from dilfolving, and decompound it: and if the patient have any acidities in the fird paffages, matters ca¬ pable of neutralifing them diould be prefcribed him ; as prepared crabs eyes, and other abforbents known in me¬ dicine : In fuch cafes thofe with which the foap is com¬ pounded in Mrs Stephen’s remedy may be of ufe. To combine Fat Oils ’with Sulphur. Put any fat oil whatever into an earthen veffel; add to it about a fourth part of its weight of flower of ful- phur, and fet the veffel in a furnace, with lighted coals under it. When the oil hath acquired a certain degree of heat, the fulphur will melt, and you will fee it fall immediately to the bottom of the oil, in the form of a very red fluid. The two fubdances will remain thus fe- parated, without mixing together, while the heat is no greater than is neceffary to keep the fulphur in fufion. Increafe it therefore ; but flowly, and with circtimfpec- tion, led the matter take fire. When the oil begins to fmoke, the two liquors will begin to mix and look tur¬ bid : at lad they will unite fo as to appear one homoge¬ neous whole. If you keep up the heat, fc that the mix¬ ture diall always continue fmoking and ready to boil, you may add more fulphur, which will perfedly incor¬ porate with it: and thus may a pretty confiderable quan¬ tity thereof be introduced into this compofition.' To combine Fat Oils •with Lead, and the Catxes of Lead. The Bafis of Piafsrs. The Deeompoftion of this Combination. Into an earthen veffel put granulated lead, litharge, cerufe, or minium ; and pour thereon twice its weight of any fat oil whatever. If you fet the veffel over a Briffc fire, the lead at bottom will melt before the oil begin to boil. When it boils, dir the matter with a dick : the lead, or the calx of lead, will gradually difappear, and at lad be totally diffolved by.the oil, to which it will give a very^thick .Qonfidence. Fat oils diffolve not only lead, but its calxes alfo: nay, they diffolve the latter more reacv.y than lead in fubdance ; probably becaufe they are more divided. The refult of a combination of thefe matters is a thick, tena¬ cious mafs, that grows in fome degree hard in the cold, and foft by heat. This compofition is known in phar¬ macy by the name oi plajler. It is made up with feve¬ ral drugs into pladers, which partake of the virtues of thofe drugs ; fkat it is the bafis of almod all pladers. Lead itfelf is feldom ufed to make pladers : cerufe, litharge, or minium, are preferred to it; becaufe thefe matters unite more readily with oils. Of 152 C H E M Of the Subftances obtained from Vegetables with a Degree of heat not exceeding that of boil¬ ing Water- To obtain from Plants, by cl filling them 'with the mean Degree of heat between freezing and boiling Water, a Liquor impregnated with their Principle cf Odour. In the morning, before fun-rife, gather the plant from which you defign to extra# its odoriferous water. Chufe the plant in its full vigour, perfedlly found, and free from all adventitious matters, except dew. Put this plant, without fqueezing it, into the body of a tin¬ ned copper alembic, and fet it in a water bath. Fit on its head, and to the nofe thereof lute a glafs receiver with wet bladder. Warm the bath to the mean degree between freezing and boiling water. You will fee a liquor diftill and fall drop by drop into the receiver. Continue the diftilla- tion with this degree of heat, till no more drops fall from the nofe of the alembic. Then unlute the velfels; and if you have not as much liquor as you want, take out of the cucurbit the plant already diftilled, and put a frefh one in its place. Diftill as before, and go on thus till you have a fufficient quantity of pdorife^ rous liquor. Put it into a bottle; ftopit-clofe; and fet ■ it in a cool place. The liquor obtained from plants, with the degree of heat here preferibed, confifts of the dew. that was on the plant, and fome of the phlegm of the plant itfelf, toge¬ ther with its odorous principle. Mr Boerhaave, who examined this odoriferous part of plants with great care, calls it the fpiritus reflor. The nature of this fpirit is not yet thoroughly afeertained ; becaufe it is'fo very vo¬ latile, that it cannot eafily be fubjefted t6 the experi¬ ments. that are neceflary to analife it, and to difeover all its properties. If the bottle containing the liquor, which may be confidered as the vehicle of this fpirit, be not exceeding carefully flopped, it flies quite off: fo that in a few days nothing will be found but an infipid inodorous water. Great part of the virtue of plants refides in this their principle of odour; and to it mult be aferihed the molt lingular and the molt wonderful effedts we every day fee produced by them. Every body knows that a great number of odorous plants affedt, in a particular manner, • by their feent only, the brain and -the genus nervofum, of fuch efpecially whofe nerves are very fenfible, and fuf- ceptible of the tlighteft impreflion; fuch as hypochon¬ driacal of melancholy men, and hyfterical women. The fmell of the tuberofe, for inftance, is capaible of throw¬ ing fuch perfons into fits, fo as to make them drop down and fwoon away. The fmell of rue again, which is equally ftrortg and penetrating, but of a different kind, is a fpe- cific remedy againft the ill effedts of the tuberofe; and brings thofe perfons to life again, with as quick and as furprifing an efficacy as that by which they were reduced to a ftate not unlike death. This is Mr Boerhaave’s ob- fervation. I S T R Y. Tire odorous exhalations of plants muft be confidered as a continual emanation of their fpiritus reflor \ but as growing plants are in a condition to repair, every in- ftant, the Ioffes they fuftain by this means, as well as by tranfpiration, it is not furprifing that they are not foon exhaufted while they continue in vigour. Thofe, on the contrary, which we diftill, having, no fuch refource, are very foon entirely exhaufted of this principle. The feparation of the fpiritus reflor from plants re¬ quires but a very gentle-heat, equally diftant from the freezing point, and from the heat of boiling water. Ac¬ cordingly the heat of the fun in fummer is fufficient to diflipate it almoft entirely. This {hews why it is dange¬ rous to ftay long in fields, or woods, where many noxi¬ ous plants grow. The virtues of plants refiding chiefly in their exhalations, which the heat of the fun increafes confiderably, a fort of atmofphere is formed round them, and carried by the air and the wind to very great di- ftances. For the fame reafon the air of a country may be ren¬ dered falutary and medicinal, by the exhalations of wholefome plants growing therein. From the facility with which the odorous principle of plants evaporates, we learn what care ought to be taken in drying thofe in¬ tended for medical ufes, fo as to preferve their virtues. They ntu,ft by no means be expofed to the fun, or laid in a warm place: a cool, dry place, into which the rays of the fun never penetrate, ,js the propereft for drying plants with as little lofs of theft ^.virtue as poflible. - Though there is reafon to believe that every vegetable matter hath a fpiritus reftor, feeing each hath its parti¬ cular feent, yet this principle is not very perceptible in any but thofe which have a very manifeff odour: and ac¬ cordingly it' is extradted chiefly from aromatic .plants, or the moft odoriferous parts of plants. To extrafl the Fat Oils of Plants by the Decoflion in boiling Water. Cacao-Butter. Pound or bruife in a marWe mortar your vegetable fubftances abounding with the fat oil which you intend to extra# by deco#ion: tie them up in a linen cloth: put this packet into a pan, with feven or eight times as much water., and make the water boil. The oil will be feparated by the ebullition, and float on the furface of the water. Skimiit off carefully with a ladle, and con¬ tinue boiling till no more oil appear., The heat of boiling water is capable of feparating the fat oils from vegetable matters that contain any: but this is to be effe#ed by a#ua] decoftion only, and not by di- ftillation; becaufe thefe oils will not rife in an alembic with the heat of boiling water. We are therefore ne- ceflitated to colle# them from the furface of the water, as above direffed. The water ufed in this co#ion generally becomes milky, like an emulfion. Neverthelefs this way of obtaining the fat oils is not generally pra#ifed ; becaufe the heat, to which they are expofed in the operation, occafions their being lefs mild than they generally are: but it is an excellent method, and indeed the only one that can be employed, for extrafting from particular vegetables cer¬ tain concrete oily matters, in the form of butteror wax ; ‘ which C H E M which matters are no other than fat oils in a fixed ftate. The cacao yields, by this means, a very mild butter; and in the fame manner is a wax obtained from a certain fix rub in America. To extraft the Effential Oils of Plants hy diftillation •with the heat of boiling •water. Dijlilled •waters. Put into a cucurbit the plant from which you defign to extract the effential oil. Add as much water as will fill two thirds of your veflel, and dilfolve therein half an ounce of fea-falt for every quart of water you ufe. To this body fit on an alembic-head, and to the nofe there¬ of lute a receiver with lized paper or wet bladder. Set it in a furnace, and let the whole digeft together, in a very gentle warmth, for twenty-four hours. This being done, light a wood-fire under your vefTe.l, briflc enough-to make the water in it boil immediately. Then flacken your fire, and leave it juft ftrong enough to keep the water fimmering. There will come over into the re¬ ceiver a liquor of a whitifh colour, fomewhat milky ; on the furface of which, or at the bottom, will be-found an oil, which is the effential oil of the vegetable you put in¬ to the cucurbit.* Continue your diftillation with the fame degree of heat, till you perceive the liquor come off clear, and unaccompanied with an oil. When the diftillation is finilhed, unlute the receiver ; and, if the effential oil be of that fort that is lighter than water, fill the veffel up to the top with water. On this occafion a long-neckdd matras Ihould be ufed for a re¬ ceiver; that the oil which floats on the water may col- leift together in its neck, ^nd rife up to its mouth. Then in the neck of this veffel put the end of a thread of cot¬ ton twine, fo that the depending part without the veffel may be longet than that in the oil, and the extremity thereof hang within the mouth of a little phial, juft big enough to contain your quantity of oil. The oil will rife along the yarn as in a fiphon, filter through it, and fall drop by drop into the little phial-. When all the oil is thus come over, flop your little bottle very dole, with a cork coated over with a mixture of wax and a little pitch. If your oil be ponderous, and of the fort that finks in water, pour the whole contents of the receiver into a glafs funnel, the pipe of which muft terminate in a very fmall aperture that may be flopped with your fore-finger. All the oil will be colledled in the lower part of the funnel: then remove your finger, and let the oil run out into a little bottle through another fmall funnel. When you fee the water ready to come, flop the pipe of the funnel, and«cork the bottle containing your oil. To extrail the EJfential Oils of Plants by Dijlillation per defcenfum. Reduce to a powder, or a pafte, the vegetable fub- ftances from which you intend to extraft the effential oil by the method propofed. Lay this matter about half an inch thick on a fine, clofe, linen cloth. If it be dry and hard, expofe the cloth containing it to the fleam of boiling water, till the matter become moift and foft. Then lay the cloth, with its contents, over the mouth You. II. No. 36. 3 I S T R Y. ,53 of a very tall cylindrical glafs vefi'd, which is to do the office of a receiver in this diftiilation ; and, by means of a piece of fmall pack-thread, fallen down the extremities of the cloth,' by winding the thread feveral times over them and round the vefl'el; in, fuch a manner, however, that the cloth be not tight, but may yield to a fmail weight, and fink about five or fix lines deep into the veffel over which it is faftened. Set this recipient in a larger veffel, containing fo much cold water as will reach half way up the cylindrical veffel, which, having little in it but air, muft be ballafted with as much lead as will fink it to the bottom of the water On the cloth, containing the fubftance to be d'ftilled, fet a flat pan of iron or copper, about five or fix lines deep, that may juft fit the mouth of the glafs veffel over which the cloth is faftened, fo as to fhut it quite clofe. Fill tin's pan with hot allies, and on thefe lay fome live coals. Soon after this you will fee vapours defcend from the cloth, which will fill the recipient, and drops of liquor will be formed on the under fide of the cloth, from whence they will fall into the veffel. Keep up an equal gentle heat, till you preceive nothing mote difcharged. Then uncover the recipient: you will find in it two diftinft li • quors ; one of which is the phlegm, and the-oth.t the effential oil of the fubftance diftilled. Infufions, Decoctions, and Extrails of Plants. Make fome water boiling-hot, and then take it off the fire. When it ceafes to bpil, pour it on the plant of which you defire to have the infufion ; taking care there be enough of it to cover the plant entirely. . Cover the veffel, and let your plant lie in the hot water for the- ft. ice of half an hour, or longer if it be of a firm ciofe texture. Then pour off the water by inclination: it will have partly acquired the colour, the fmell, the tafte, and the virtues of the plant. This liquor is called an infufon. To make the decoftion of a vegetable fubftance, put it into an earthen pan, or into a tinned copper veffel, with a quantity of water fufficient to bear being boiled for feveral hours without leaving any part of the plant dry. Boil your plant more or lefs according to its na¬ ture ; and then pour off the water by inclination. This water is impregnated with feveral of the principles of the plant. If the infufions and decodtions of plants be filtered, and evaporated in a gentle heat, they become extradls, that may be kept for whole years, efpecially if they be evaporated to a thick confiftence ; and better ftill if they be evaporated to drynefs. Of Operations on EJfential Oils. The Keilif cation of Effential Oils. Put into a cucurbit the effential . oil you propofe to rediify. Set the cucurbit in a balneum marict; fit to it a head of tin, or of copper tinned, together with its re¬ frigeratory ; and lute on a receiver. Make the water in the bath boil, and keep up this degree of heat till no¬ thing more will come over. When the diftillation is fi- 2 Q_ niflied. 154 c H E M riifhed, you will find in the receiver a refllfied effential oil, which will be clearer, thinner, and better fcented than before it was thus before re-diflilled ; and in the bottom of the cucurbit will be left a matter of a deeper ■colour, more tenacious, more refmous, and of a lefs grateful fmell. Eflential oils, even the pureft, the bell prepared, and the thinneft, fuffer great changes, and are much impair¬ ed by growing old: they gradually turn thick and refin- ous; their fweet, grateful fcent is loft, and fucceeded by a more difagreeable fmell, fomewhat like that of turpen¬ tine. The caufe of thefe changes is, that their fineft and moft volatile part, that which contains moft of the odor¬ ous principle, is diflipated and feparated from that which contains leaft of it; which therefore grows thicker, and comes fo much the nearer to the nature of a refin, as. the quantity of acid, that was diftributed through the whole oil before the diflipation of the more volatile part, is, af¬ ter fuch diffipation, united and concentrated in the hea- vieft part; the acid in oils being much lefs volatile than the odorous part, -to which alone they owe their levity. Hence it appears what precautions are to be ufed for preferving eflential oils as long as poflible without fpoil- kig. * They rnuft be kept in a bottle perfedtly well flop¬ ped, and always in a cool place, becaufe heat quickly diffipates the volatile parts. Some authors diredt the bot¬ tle to be kept under water. To fire Oils by combining them with highly concentrated Acids: infianced in Oil of.Turpentine. Mix together in a glafs equal parts of concentrated oil of vitriol, and highly fmoking frefh-drawn fpirit of jiitre: pour this mixture at feveral times, but fuddenly, on three parts of oil of turpentine, fet for that purpofe in a glafs bafon.. By a part here muft.be underftood a dram at leaft. ' A moft violent commotion, accompanied with fmoke, will immediately be raifed in the liquors, and the whole will take fire in an inftant, flame, and be confumed. There is not in chemiftry a phenomenon more extra¬ ordinary, and more furprifing, than the firing of oils by mixing them with acids. It could never have been fufpedted, that a mixture of two cold liquors would pro¬ duce a fudden, violent, bright, and lafting flame, like that we are at prefent confidering. To combine EJfential Oils with Mineral Sulphur. Batfam of Sulphur. Put into a matras one part of flowers of fulphur ; pour on them fix parts of the eflential oil of turpentine, for inftance ; fet the matras in a fand-bath, and heat it gradually till the oil boil. The fulphur, which at firft lay at the bottom of the matras, v/ill begin to melt, and appear to diflblve in the oil. When it hath boiled in .this manner for about an hour, take the matras from the fire, and let tfie liquor cool. A great deal of the fulphur that was diflblved therein will feparate from it as it cools, and fall to the bottom of the veflel in the form of needles, much like a fait ftiooting in water. When the liquor is perfectly cold, decant it from the fulphur that lies at the bottom of the veflel: to that I S T R Y. fulphur put frefh oil of turpentine, and proceed as be¬ fore : the fulphur will again difappear, and be diflblved in the oil; but when the mixture is cold you will find new cryftals of fulphur depofited at the bottom. De¬ cant once more this oil from the cryftals, and pour on frelh oil to diflblve them: continue the fame method, and you will find, that about fixteen parts of eflential oil are required to keep one part of fulphur diflblved when cold. This combination is called balfamum fulphuris terebin- thinatum, if made with oil of turpentine ; anifatum, if with oil of anifa-feeds; and fo of others. To cotnbine EJfiential Oils with fixed Alkalis. Starkey's, Soap. Take fait of tartar, or any other alkali, thoroughly calcined. Heat it in a crucible till it be red, and in that condition throw it into a hot iron mortar: rub it quick¬ ly with a very hot iron peftle; and as foon as it is pow¬ dered, pour on it, little'by little, nearly an equal quan¬ tity of oil of turpentine. The bil will enter into the fait, and unite intimately with it, fo as to form a hard 'pafte. Continue rubbing this compofition with a peftle, in order to complete the union of the two fubftances ; and, as your oil of turpentine difappears, add more, which will unite in the fame manner, and give a fofter confiftence to the foapy mafs. You may add ftill more oil, according to the confiftence you intend to give your foap. Starkey, the firft chemift who found the means of making foap with an eflential oil, and by whofe name this kind of foap is therefore called, made ufe of a much more tedious method than that propofed in our»procefs. He began with mixing a very fmall quantity of oil with'his fait, and waited till all the oil united therewith of its own- accord, fo as to difappear entirely, before he added any¬ more ; and. thus protratfted his operation exceedingly,, though in the main it was the fame with ours. The me¬ thod here propofed is more expeditious, and was invent¬ ed by Dr Geoffrey. Starkey’s foap diflblves in water much as common foap does, without any feparation of the oil: and by this- mark it is known to be well made. It may alfo be de¬ compounded, either by diftillation, or by mixing it with an acid : and its decompofition, in either of thefe ways, is attended with nearly the fame phenomena as the de¬ compofition of common foap. Of the Subftances obtained from Vegetables by means, of a graduated Heat, from that of boil¬ ing Water, to the ftrongefl that can be applied, to them in clofe Vejfels. To analife Vegetable Subfiances that yield neither a Fat nor an EJfential Oil. Infianced in Guai'acum- wood. Take thin fhavings of Guaiacum-wood, and put them into a glafs or ftone retort, leaving one half thereof empty. Set your retort in a reverberating furnace, and lute on a large glafs feceiver having a fmall hole drilled in it, fuch as is ufed for diftilling the mineral acids. Put a C H E M I liVe coal or two in the farnace, to warm the veffels gen¬ tly and flowly. With a degree of heat below that of boiling water, yon will fee drops of a clear infipid phlegm fall into the receiver. If you raife the fire a little, this water will come llightly acid, and begin to have a pungent fmell. With a degree of fire fomewhat flronger, a water will continue to rife which will be ftill more acid, fmell ftronger, and become yellowifii. When the heat comes to exceed that of boiling water, the'phlegm that rifes will be very acid, high coloured, have a ftrong pungent fmell, like that of matters long fnioked with Wood in a chimney, and will be accompanied with. a red, light oil, that will float on the liquor in the receiver. And now it is neceflary, that the operation be carried on very cautioufly, and vent frequently given to the rare¬ fied air by opening the fmall hole in the receiver ; fuch an incredible quantity thereof ruftiing out of the wood, with this degree of heat, as may burfl: the vefi’ds to pieces, if not difcharged'frpm time to time. When this red, light oil is come over, and the air ceafes to rulh out with impetuofny, raife your fire gradu¬ ally, till the retort begin to redden. The receiver will be filled with denfe vapours; and together with the wa¬ tery liquor, which will then be extremely acid, there will rife a black, thick, ponderous oil, which will fall to the bottom of the receiver and lie under the liquor; Then give the utmoft degree of heat ; that is, the greateft your furnace will allow, and your veflels bear. With this exceflive heat a little more oil will rife, which will be very ponderous, as thick and black as pitch ; and 'the veflels will continue full of vapours that will not condenfe. At laft, when you have kept the retort exceeding red for a long time in this extremity of heat, fo that it be¬ gins to melt if ft be of glafs, and you perceive nothing more come over, let the tire'go out and the veflel cool. Then take off your receiver : from the black oil at bot¬ tom decant the acid liquor with the red oil floating on it, and pour them both into a glafs funnel, lined with brown filtering paper, and placed over a bottle. The acid liquor will pafs through the filter into the bottle, and the oil v^ill be left behind, which mull be kept by it- felf in a feparate bottle. Laftly, into another funnel, prepared as the former, pour the thick oil remaining with a little of the acid liquor at the bottom of the re¬ ceiver. This liquor will filter off in the fame manner, and thus be feparated from the heavy oil. In the retort you will find your Guaiacum fhavings not in the leaft altered as to their figure, but light, friable,, very black, fcentlefs and taftelefs, eafily taking fire, and confuming witflouTHame or fmoke: in fliort you will find them charred to a pe'rfeA coal. Hi t h e a t o we have examined the fubftances that may be obtained from vegetables, either without the help of fire,, or with a degree -of heat not exceeding that of boil¬ ing water. The analyfis of plants can be carried no further without a greater degree of heat: for, when the principle of odour and the elfential oil of an aromatic S T R Y. 155 plant are wholly extracted by the preceding procefles, if the dirtillation be afterward continued without increafing the heat, nothing more will be obtained but a little acid; W'hich will foon ceafe, as a fmall part only of the quan¬ tity contained in the plant will be elevated; the reft be¬ ing either too ponderous, or too much entangled with the other principles of the body, to rife with fo fmall a degree of heat. In order therefore to carry on the decompofition of a plant, from which you have*, by the methods before pro- pofed, extradted all the principles it is capable of yield¬ ing when fo treated ; or, in order to analife a vegetable matter, \yhich affords neither an exprefled nor an eflen- tial oil, it muft bediftilled in a retort with a naked fire, as dire&ed in the procefs, and be made to undergo all the degrees of heat fueceflively, from that of boiling water to the higheft that can be raifed in a reverberating furnace- A heat inferior to that of boiling water, with which we muft begin in order to warm the vefleLgradually,, brings nothing over, but an infipid water, deftitu.te of all acidity. By increafing it nearly to the degree of boiling water, the diftilled water comes to be flightly acid. When the heat is made a little ftronger than that which is neceflary for^he elevation of an efi’ential oil, the acidity of the water that comes off is much more confi- derable. It hath now both colour and fmdl, ihd there rifes with it a red, light oil, that floats on the liquor in the receiver. This is not an eflential oil; it hath none of the odour of the plant. Though fo light as to float on water, yet it will not rife with the degree of heat that raifes eflential oils, even thofe that much furpafs it in gravity, and. will not fwim on water as they do. This proves, that the eafe or difficulty with which a particu¬ lar degree of heat raifes any fubftance in diftilktion doth not depend altogether on its gravity : its dilatabi- lity, or the volatile nature of the matters with wdrich it is fo clofely united as not to be feparated from them by diftillation, mayj>robably contribute greatly to produce this effedt. It is very furprifing, that a fubftance fo hard,, fo com- padt, fo dry in appearance, as Guaiacum-wood, fiiould yield fuch a large quantity of water by diftillation; and it is equally fo, that it fhould difcharge fo much air; and- with fo much impetuofity, as nothing but experience could render credible. It hath been remarked, that the heavieft and moft com- padt woods yield the moft air in diftillation: and accor¬ dingly Guaiacum-wood, as exceeding almoft all others in hardnefs and weight, difcharges a vaft quantity of air when analifed. The thick, burnt, empyreumatic oil, that comes over kft in this diftillation, is heavier than water; on ac¬ count, probably, of the great quantity of acid with which it is replete. The two kinds of oil obtained, in this analyfis may be redlified, by diftilling them, a fecond time, or rather fi;veral times; by which means they will become lighter and more fluid. In, general, all thick, heavy oils conftantly owe thefe qualities to an acid, united with them ; arid it is by being freed from fome of that acid in diftillation, that they always acquire a great- C H E M er degree bf lightnefs and fluidity from that operation. The anaiyfis of a vegetable fubftance, (hews what may be obtained from them -when diirilled in dofe veffeis, with a graduated heat, from that of boiling water, to that which converts the mixt to a perfect coal; viz. phlegm, an acid, a light oil, much air, and a thick oil. But this anaiyfis is far from being a complete one : it may be carried much farther, and made more perfeft. None of the principles obtained by this anaiyfis are pure, fimple, and thoroughly feparated from the reft. They are ftill in fome meafure blended all together: their reparation is but begun; a^d each requires a fecond and more accurate anaiyfis,' to reduce it to the greateft degree of purity of which it is capable. The oil and the acid chiefly merit fo much pains. A great deal of the acid of the plant remain^, com¬ bined with the two forts of oil here obtained ; which we have reafon to .think differ no otherwife from one another, "than as there is more or lefs acid united with, 'each. The beft way of freeing tfhefe oils from their re¬ dundant acid is to diftill them frequently from alkalis and abforbents. The acid is in the fame cirbumftances nearly as the oil. The firft that rifes is mortified with much water, to which it owes a good deal of its volatility. That which comes over laft is much more concentraied, and confe- quently heavier;' yet it is ftill very aqueous. It might be freed in a great meafure from this adventitious water, and fo rendered much ftronger ; which would give us a better opportunity to difcover its nature and properties, of which we know but very Httle. Water is pot the only heterogeneous fubftance that difguifes'the vegetable acid: a pretty confiderable quan¬ tity of the oil of the plant is alfo combined with it, and contaminates its purity. The proof ot this is, that when thefe acids are kept, in the fame condition in which they firft come over, for any length of time, in a glafs veffel, they gradually depofite, on the bottom and fides of the veffel, an oily incruftation, which grows thicker and thicker the longer it ftands; and, as this oily mat¬ ter feparates from it, the acid liquor appears lefs un&u- ous and faponaceous. A very good way to feparate this oil more effedtually from the acid is to combine the whole with abforbents, and abftraft the oil again by diftillation. By this means a very fenfible quantity of oil may be feparated that was not perceived before. The air, that is difcharged with impetuofity in the o- peration, and mull be let out, is loaded with many par¬ ticles of acid and oil reduced to vapours, which it carries off; and by this means the quantity of the principles extracted from the mixt cannot be accurately determined: nor are the vapours, of which the veffels remain full af¬ ter the operation, any other than particles- of acid and oil, which the violence of the fire hath rarefied exceedingly, and which doyiiot eafily condenfe. If we diftill in this manner a vegetable aromatic fub¬ ftance, which of courfe contains an effential oil, provided it hath not been previoufly extradled by the appropriated procefs, this effential oil will rife firft, as foon as the diftil- ling veffel acquires the heat of boiling water; but its 1 S. ' T R Y. fcent will not be near fo fweet or grateful, as if it were diftiiled in the manner before directed as propereft for it. On the contrary, it will have an empyreumatic fmell: becanfe in this way it is impollible to avoid fcorching, and half-burning fome of the matter diftiiled ; efpecially that part of it which touches the fides of the retort. Moreover, the very fame equable degree of heat can hardly be kept up with a naked fire. The efferitial oil therefore, though it rifes firft, will not be pure, but con¬ taminated with a mixture of the empyreumatic oil that firft comes over, and will be confounded therewith. Mofl vegetable fubftances, when diftiiled with a ftrong fire, yield the fame principles with that which we have chofen for an inftance. Entire plants of this kind, thole from which the odorous principle, the effential oil, or the fat oil, hath been drawn, thofe of which extra&s have been made by infufion or decoftion, or the extracts themfelves; all fuch matter being diftiiled yield a phlegm, an acid, a thin oil, air, and a thick oil; and the pro- duds of their feveral analyfes- differ from each other, on¬ ly on account of the different quantity or proportion that each contains of the principles here enumerated. But there are many other plants, which, befides thefe fubftances, yield alfo a confiderable quantity of a vola¬ tile alkaline fait. This property is poffefted chiefly by that tribe of plants which is diftinguifhed by having cru¬ ciform flowers; among which there are fome that, being analifed, greatly refemble animal-matters. We fhall now analife one of thefe; muftard-feed, for inftance. To analife a Vegetable Subjlance •which yields the fame Principles as are obtained from Animal-mat¬ ters : inflanced in Muflard-feed. v With an apparatus like that of the preceding -pro¬ cefs, and with the fame fire, diftill muftard-feed. With a degree of heatr inferior to that of boiling water, there will come over a phlegm fomewhat coloured, and im¬ pregnated with a volatile alkaline fait. With a degree of heat, greater than that of.boiling water, the fame kind-of phlegm, impregnated with the fame fait, will continue to come over; but it will be much higher co¬ loured, and will be accompanied with a light oil. At this time a confiderable quantity of air is difcharged; with regard to which the fame precautions muft be taken as in diftilling Guaiacum. If the fire be gradually raifed, there will come over a black thick oil, lighter however than water; and at the fame time vapours will rife, and, condenfing the fides of the receiver, form into fprings or ramifications. This is a volatile alkaline fait, in a concrete form, like that of# animals, as we fhall hereafter fee. Thefe vapours are much whiter than thofe of Guajacum. When you have thus drawn off, with a very ftrong fire, all the volatile alkali and thick oil contained in the fubjetft, there will be nothing left in the retort but a fort of coal, from which a fmall quantity of phofphorus may be obtained, provide^ the retort you employ for that purpofe be good enough to Hand a very violent heat. Muftard-feed furnifhes us with an inftance of a ve¬ getable, from which we obtain, by analifing it, the very fame principles that animal-matters yield. Inftead C H E M 1 of getting an acid from it, we obtain only a volatile alkali. We fliall pot here fpeak of tbe mariner of feparating and depurating the principles obtained by this procefs ; but referve it for the analyfis of animals, which is abfo- lutely the fame. ^Ve (hall content ourfelves with obfer- ving, that the firft volatile alkali, which rifes at the be¬ ginning of the operation together with the phlegm, in a degree of heat below that of boiling watet, differs from that which doth not come over till towards the end of the diftillation, when the. laft thick oil afcends. The differ¬ ent times, and different degrees of heat, in which thefe two alkalis rife, lhew that the former exifts actually and perfedly in the plant; but that the lafter is generated duringthe diftillation, and is the product ofvthe fire, which combines together the materials whereof it is compofed. Vegetables, that thus yield a volatile a'lkali with a heat lefs than that of boiling water, irritate the organ of fmelling, affecting it with a fenfation of acrimony; and the effluvia, which rife from them when bruifed, make the eyes linart fo as to draw tears from them in abun¬ dance. Several of thefe matters, being -only bruifed, effervefce with acid?: effe&s producible only by a very volatile, alkaline principle. This is that alkali, the lighted of all the principles that can be extradted from bodies, which rifes firff in our diftillation along with the phlegm, and with a' degree of heat much inferior to that of boiling water. As the phlegm with which it rifes is very Copious, it is diffol- ved thereby; which is the reafon it doth not appear in a concrete form. To this water it gives a flight yellow- ifh tinge, becaufe it is impure and oily. The faline al¬ kaline properties of this liquor have procured it the title of a volatile fpirit. This volatile alkali, which exifts naturally and perfedlly formed in muftard-feed, onions,, garlick, creffes, and other fuch vegetables, conftitutes a difference between them and animal fubftances, which contain only the materials requifite to form a volatile al¬ kali, but none ready formed, unlefs they have undergone the putrid fermentation. The fecond volatile alkali, which rifes in our diftilla'- tion, but not without averyftrong degree of fire, and at thb fame time with the laft thick oik feems to be a pro- dudlion of the.fire ; for, if it were already formed in the mixt, as the other is, it would rife with the fame heat, and at the fame time, being equally volatile. Of the Subfinnces obtained from'Vegetables by Combuftion. To procure a fired Caufiic Alkaline Salt from a Ve¬ getable Sub/lance, by burning it in the open Air. Take any. vegetable matter whatever ; fet it on fire, ^nd let it burn in the open air till it be wholly reduced to alhes. On thefe afiies pour a quantity of boiling wa¬ ter fufficient to drench them thoroughly. Filter the li¬ quor, in order to feparate the earthy parts; and evaporate your lye to drynefs, ftirring it inceflantly ; and you will have a yellowifh-white fait. Put this fait in a crueible ; fet it in a melting furnace, and make a moderate fire, fo as not to fufe the fait. It Vol. H. No. 36. 3 S T K Y. 157 will turn fit ft of a blue-grey colour:, qfterwards-ef a blue* green, and'at laft reddilh. put on the dome of the fur¬ nace'; fill it with coals; make your fire ftrong enough to melt the fait, and keep it in fufion for an hour, or an hour and half. Then pour it into a heated metal mor¬ tar ; pound it while it is red-hot ; put it as foon as pcf- fible into a glafs bottle, firft made very hot and dry, and /hut it up clofe with a glafs ftopple rubbed with eme¬ ry. By this means you will have the pure fixed alkali of the vegetable fubftance you burnt. Burning a vegetable fubftance in the open air is a kind of violent and rapid analyfis made by fire, which fepa- •rates, cefolves^ and decompofes feveral of its principles. When any wood or plant is laid on a quick fire, there afcends from it immediately an aqueous fmoke, which confifts of little more tlvn phlegm; but this frhoke foon becomes thicker and blacker ; it is then pungent, draws tears from one’s eyes, and excites a cough if drawn into the lungs with the breath. Thefe effedls atife from its being replete with the acid, and.fome of the oil, of the vegetable converted into vapours. Soon after this the fmoke grows exceeding black and thick; it is now ft.11 more acrid, and the plant turns black. Its ftrongeft a- cid and laft thick oil are now difcharged with impetuo- fity. ‘ This rarefied oil being heated red-hot fuddenly takes fire and flames. -The vegetable burns and deflagrates rapidly, till all its oil is confumed. Then the flame ceafes; and nothing remains but a coal, like that found in a retort after all the principles of a plant have been ex- trafted by the force of fire. Bat this coal having a free communication with the air, which is abfolutelyneceffary to keep a'combuftible burning, continues to be red, fparkles, and waftes till all its phlogjfton is diflipated and deftroyed. After this nothing remains but the earth and fixed fait of the vegetable; which,, mixed together, form-what we call the afhes. Water, which is the natural folvent of falts, takes up eVfery thing of that kind that is contained in the alhps ; fo that by lixiviating thenij as direded, all the 'fait is extracted, and nothing left but the pure earth of the mixt which is thus decompofed. The phenomena, obferved in the burning of a vegetable fubftance, and the produdion thereby of a fixed alkali, feem to prove that this fait is the wqik of the fire; that it did not exift in the plant before it was burnr; that the plant only contained materials adapted to form this fait; and that this fait is no other than^a combination of fome of the acid, united with a portion of earth, by means of the igneous motion. The alkali obtained from the allies of burnt plants is not pcrfedly pure : it is contaminated with a fmall mix¬ ture of fatty matters, which were probably defended thereby againft the adion of the fire, and which render it fomewhat faponaceous. In order to free it from this extraneous matter, and to render it very cauftic, it muft be calcined a long time in a crucible, but'without melt- vingitat firft; becaufe it is with this fait as with moft me¬ tallic matters, which are fooner and more eafily deprived of their phlogifton by being calcined without melting, provided theybe comminuted into fmall particles, than when, they are in fufion ; all melted'matters having but 15B C IT E M a'fmall furface expofed to the air, by the contadt of which the evaporation of any thing whatever is exceed¬ ingly promoted. To procure the fixed Salt of a Plant, by burning it after the manner of Tachenius. Into an iron pot put the plant whofe fait you defire to obtain in the manner of Tachenius, and fet it over a fire, ftrong enough to make its bpttom red-hot; at fhe' fame time cover your plant with a plate of iron, that may lie immediately upon it in the pot. The plant will grow black, and fmoke confiderably; but .will not flame, be- caufe it hath not a fullicient communication with the air. The black fmoke only will efcape through the in- terftice left between the fide of the pot and the rim of the plate; which, for that pur^ofe, ftiould be made fo as not to fit exaftly into the pot. From time to time take up the iron plate, ftir the plant, and cover it again immediately, to prevent its taking fire, or to fmother it if it fliould happen to flame : go on thus till the black fmoke ceafe. Then take off the iron plate: the upper part of the half-burnt plant will take fire as foon as the air is ad¬ mitted, confume gradually, and be reduced to a white afli. Stir your, matter with an iron wire, that the un- dermoft parts, which are ftill black, may be fucceflively brought uppermoft, take fire, and bui^i to white afhes. Go on thus as long as you perceive the leaft blacknefs remaining. After this, leave your afhes fome time longer on the fire; but ftir them frequently, to the end that, if any black particles Ihould ftill be left, they may be entirely confumed. Your afhes being thus prepared, lixiviate them with feven times their quantity of water, made to fimmer o- ver the fire, and keep ftirring it with an iron ladle. Then filter the liquor, and evaporate it to drynefs in an iron pot, ftirring it inceffantly towards the end, left the matter, when it grows ftiff, fhould adhere too clofely to the veffel. When all the humidity is evaporated, you will have a fait of a darkifh colour and alkaline nature; which you may melt in a crucible, and mould into cakes. This is the fixed fait of plants, prepared in the manner of Tachenius. To render Fixed Alkalis very caujlic by means of Lime. The Cauftic Stone. Take a lump of newly burnt quick-lime, that hath not yet begun to flake in the air : put it into a ftone pan, and cover it with twice its weight of the unwafhed afhes of fome plant that are full of the fait you defign to ren¬ der cauftic. Pour on them a great quantity of hot wa¬ ter ; let them fteep in it five or fix hours, and then boil them gently. Filter the liquor through a thick canvas bag, or through brown filtering paper fupported by a linen cloth. Evaporate the filtered liquor in a copper bafon fet over the fire ; and there will remain a fait, which muft be put into a crucible fet in the fire. It will melt, and boil for fome time ; after which it will be ftill, and look like an oil, or melted fat. When it comes to this condition, pour it out on a very hot copper plate, and cut it into I S T R Y. oblong tapering flips, before it grow hard by cooling* Put thefe flips, while they are ftill hot, into a very dry glafs bottle, • and feal it hermetically. This is the caufitc ftone, or common caufiic. The Analyfis of Soot. Take wood-foot from a chimney under which no ani¬ mal matter hath been dreffed or burnt: put it into a glafs retort fet in a reverberating furnace ; lute on a receiver, and begin to diftill with a degree of heat fomewhat lefs than that of boiling water. A confiderable quantity of limpid phlegm will come over. Keep the fire in the fame degree as long as any of this phlegm rifes, but increafe it when the drops begin to come flow; and then there will afcend a good deal of a milky water. When this water ceafes to run, change the receiver, and increafe your fire a little : a yellow volatile fait will rife, and ftick to the fides of the receiver. The fire ought now tb be very fierce, and, if fo, will force up at the fame time a very thick black oil. Let the vefleis cool: you will find a faline matter rifen into the neck of the retort, which could not pafs over into the receiver : in the bot¬ tom of the retort will be a caput mortuurn, or black charred fubftance, the upper part of which will be cruft- ed over with a faline mattqr, like that in the neck of the retort. As we are at prefent inquiring into the nature of ve¬ getables only, it is evidently neceflary that we chufe a foot produced by burning vegetables alone. Soot, though dry in appearance, contains neverthelefs much humidity, as appears from this analyfis ; feeing there comes over at firft a confiderable quantity of phlegm, that doth not feem to be impregnated with any principle, except perhaps an extremely fubtile, faline, and oily matter, that commu¬ nicates to it a difagreeable fmell, from which it cannot by any means be. entirely freed. The volatile alkali obtained from foot is, in a double refpedt, the produft of the fire. In the firft place, though it derives its origin wholly from wood, or other vege¬ tables, which, when diftilled in clofe veflels, yield no volatile alkali at all, yet it produces fuch a fait when a- nalyfed in the prefent manner : whence it muft be in¬ ferred, that the principles of thofe vegetables are meta- morphofed into a volatile alkali, by being burnt in the open air, and fublimed in the form of foot. Secondly, though foot, when analyfed, yields a great deal of this fait, yet this fait doth not formally pre-exift therein ; for it doth not rife- till after the phlegm, nor without a very confiderable degree of heat: therefore foot contains only the materials neceffary to form this fait ; therefore the perfect combination of this fait requires that the force of fire be applied a fecond time ; therefore it is, as was faid, doubly the product of the fire. The faline matter which we find fublimed into the neck of the retort, and which alfo forms the cruft that covers the caput mortuum of the foot, appears by all chemical trials to be an ammoniacal fait; that is, a neu¬ tral fait, confifting of an acid and a volatile alkali. This ammoniacal fait rifes only into the neck of the retort, and doth not come over into the receiver; becaufe it is but femi-volatile. We 'ftiall treat more at large of the produftion C H E M produttion of a volatile alkali, and of this ammoniacal fait, when we come to the analyfis of animals, and the article of fal ammoniac. 'The Analyfis of fome particular Subftances be- ■ longing to the Vegetable Kingdom. Analyfis of the natural Balfams : infanced in Tur¬ pentine. Into a cucurbit put as much rain-water as will fill about a fourth part of its cavity, and pour into it the turpentine you intend to analyfe. Cover the cucurbit' with its head, and lute it on with flips of fized paper or wet bladder. Set your alembic in a fand-heat; lute on a long-necked receiver ; and give a gradual fire till the water in the cucurbit boil. There will come over into the receiver a good deal of phlegm, which, by little and little, will become more and more acid ; and at the fame time there will rife a great quantity of an aethereal oil, extremely light, fluid, and as limpid and colourlefs as water. When you obferve that no more oil comes off, unlute your veffels ; and in the receiver you will find an acidu¬ lated water, and the aethereal oik floating on it. Thefe two liquors may be eafily feparated from each other, by means of a glafs funnel. In the cucurbit will be left fome of the water you put in, together with the remainder of your turpentine ; which, when cold, inftead of being fluid, as it was before diftillation, will be folid, and of the confidence of a relin, and is then called rofn. Put this refiduum into a glafs retort, and diftill it in a reverberatory with a naked fire, gradually increafed ac¬ cording to the general rule for all diftillations. At firft, with a degree of heat a little greater than that of boiling water, you will fee two liquors come over into the reci¬ pient ; one of which will be aqueous and acid, the other will be a tranfparent, limpid, yellowilh oil, floating on the acid liquor. Continue your diftillation, increafing your fire from time to time, by flow degrees. Thefe two liquors will continue to come ofif together ; and the nearer the ope¬ ration draws to its end, the more acid will the aqueous liquor become, and the thicker and deeper coloured will the oil grow. At laft the oil will be very thick, and of a deep reddifli-yellow colour. When nothing more a- fcends, unlute your veflels : in the retort you will find only a very fmall quantity of a charred, light, friable fubftance. All natural balfams, as well as turpentine, are oily, aromatic matters, which flow in great quantities from the trees containing them, either fpontaneoufly, or thro’ incifions made on purpofe. As thefe matters have a ftrong fcent, it is not furprifing that they ftiould greatly abound with effential oils. They may even be confi- dered as eflential oils, that naturally, and of their own accord, feparate from the vegetables in which they exift. Natural balfams, and efl’ential oils grown thick with age, are exactly oae and the fame tiling. Accordingly I S T R Y. 159 we fee that fire and diftillation produce th6 fame effefls on both. The re&ification of an eflential oil, thickened by keeping, is nothing but a decompofition thereof, by feparating, with the heat of boiling water, all' thole parts that are light enough to rife with that degree of heat, from what is fo loaded with acid as to remain fixed therein. The newer natural balfams are, .the thinner they are, and the more eflential oil do they yield ; and this eflen- tial oil, like all others, grows thick in time, and at laft: turns again to an aftual balfam. Thefe balfams, by being long expofed to the heat of the^fun, acquire fuch a confiftence as to become folid. They then take another name, and are called ref ns. Refins yield much lefs eflential oil when diftilled, than balfams do. Hence it follows, that refins are to balfams, what balfams are to eflential oils. The Analyfs of Ref ns : infanced in Benjamin. The Flowers and Oil of Benjamin. Into a pretty deep earthen pot, having a border or rim round its mouth, put the benjamin you intend to a- nalyfe. Cover the pot with a large conical cap of very thick white paper, and tie it on under the rim. Set your pot in a fand-bath, and warm it gently till the benjamin melt. Continue the heat in this degree for an hour and half. Then untie the paper cap and take it off, (baking it as little as pcffible. You will find all the infide of the cap covered with a great quantity of beautiful, white, (hining flowers, in the form of little needles. Brufti them off gently with a feather, put them into a bottle, and ftopi it clofe. As foon as you take off the firft cap, cover your pot immediately with a fecond like the former. In this man¬ ner go on till you perceive the flowers begin to grow yellowifh ; and then it is proper to defift. The matter left in the pot will be blackilh and friable when cold. Pulverife it; mix it with fand ; and diftill it in a glafs retort with a graduated heat. There will come over a light oil, of a fragrant fcent, but in very fmall .quantity; a little of an acid liquor, and a great quantity of a red thick oil. There will be left in the retort a charred, fpungy fubftance. Of the Nature and Properties of Camphor. We do not propofe to give an analyfis of this lingular Body; becaufe hitherto there is no procefs known in chemiftry by which, it can be decompofed. We (bail' therefore content ourfelves with reciting its principal pro¬ perties, and making a few reflexions on its nature. Camphor is an oily concrete fubftance ; a kind of re¬ fin, brought to us from the ifland of Borneo, but chiefly from japan. This fubftance refembles refins, in being inflammable, and burning much as they do ; it is not fo luble in water, but diftcives entirely and perfeXly in fpi- rit of wine; it is eafily feparated again from this merr- ftruum, as all other oily matters are, by the addition of water; it diflblves both in expreffed and in diftilled oils ; it hath a very ftrong aromatic fmell. Thefe are the chief 160 C H E Tvl chief properties which camphor ^oiTeHes in common'with refins : but in other relpefts it diiFers totally from them ; efpecially in the following particulars. Camphor, takes fire and flames with vafily more eafe than any other refin. It is fo very volatile, that it va- nifhes entirely in the air, without any other heat than that of the atmofphere. In diflillation it rifes. entire, without any decompofition, or even the leafl: alteration. It diiToIves in concentrated mineral acids ; but with cir- cumftances very different from thofe that attend other oily or refinous fubflances. The diilbltition is accompa¬ nied with no effervefcence, no fenfible heat; and confe- quently can produce no inflammation. Acids do not burn, blacken, or thicken it, as they do other oily mat- -ters ; on the contrary, it becbmes; fluid, and runs with them into a liquor that looks like oil. Camphor doth not, like other, oily matters, acquire a difpofuion to diffplve in water by the union it contracts with acids ; though its union with them feems to be more intimate than that of many oily matters with the fame a- cids.. On the contrary, if a combination of camphor and an acid be diluted with water, thefe two fubftances in- flantly feparate from each other : the acid unites with the water, and the. camphor, being entirely difengaged from it, fwims on the fur face of the liquor. Neither volatile alkalis, nor the mod cauftjc fixed alkalis, can be brought into union with it; for it always eludes their power. NotwithfLrnding thefe wide, differences between cam¬ phor and all other oily and. xefinoua. fubftances.* the rule, that acids thicken oils, feem^ to be fo univerfai, and fo conftantly obferved by nature, that we cannot help think¬ ing this fubftance, like all the reft, is an oil thickened by an acid. But what oil i wh,at acid ? and how are they united ? This is a fubje£t for very curious inqui¬ ries. . , ,, , , ; ‘ ■ With a yellqw oil drawn from wine, and an acid vi¬ nous fpirit, Mr Hellot made a kind of artificial cam¬ phor; a fubftance having the odour, favour, and inflam¬ mability of camphor; an ..camphor. True camphor hath the levity, the volatility, and the inflam¬ mability of aether.. Can it be a fubftance of the fame nature with tether, a kind of folid aether, an aether in a concrete form ; 77;? Analysis of Bitumens : injlanced in Amber. The Volatile Salt and Oil of Amber. Into a glafs retort put fome fmall bits of amber, fo as to fill but two thirds of the veffel. Set your retort .in a furnace covered with its dome ; fit on a large glafs re¬ ceiver ; and beginning with a very gentle heat, diftill with degrees of fire. Some phlegm will firft come off, which will gradually grow more acid, and be fucceeded by a volatile fait, figured like fine needles, that will ftick to the fides of the receiver. Keep the fire up to this degree, in order to drive over all the fait. When you perceive that little or none rifes, change the receiver, and increafe your fire a little. A light, clear, limpid oil will afcend. As the diftilla- tion advances, this oil will grow higher coloured, lefs I S T R Y. limpid, and thicker ; till at lad it will be opaque, black, and have the confiftence of turpentine. When you perceive that, though the retort be red-hot, nothing more comes off, let the fire go out. You will have in the retort a black, light, fpungy coal. If you have taken care to drift the receiver, from time to time, during the diftillation of your oil, you will have fundry feparate portions thereof, each of which will have a dif¬ ferent degree of tenuity or thicknefs, according as k came over at the beginning, or towards the end of the di- jftillation. The fubftance of which we have here given the ana- iyfis, together with all others of the fame, that is, of the bituminous kind, is, by moft chemills and naturalifls, claffed with minerals : and lb far they are right, that we actual¬ ly get thefe mixts, like other minerals, out of the bowels of the earth, and never procure them immediately from any vegetable or animal compound. Yet we have our reafons for aCting otherwife, and for thinking that we could not, in this work, place them better, than imme¬ diately after thofe vegetable fubftances which we call re- fins. Several motives determine us to proceed in this man¬ ner. The analyfis of bitumens demonftrates, that, with regard to the principles of which they confift, they are totally different from every other kind of mineral ; and that, on the contrary,' they, greatly referable vegetable refins in almoft- every refpeCt. In ftiort, though‘they are not immediately procured from vegetables, there is the greateft reafon for believing that they were originally of the vegetable kingdom, and that they are no other than refinous and oily parts of trees, or plants, which by lying long in the earth, and there contracting an union with the mineral acids, have acquired the qualities that diftinguilh them from refins. Mineralogifts know very well that we find, every where in the earth, many vegetable fubftances, that have lain very long buried under it, and frequently at a con- fiderable depth. It is. not uncommon to find, under ground, vaft beds of folWe trees, which feem to be the remains of immenfe forefts : and bitumens, particularly amber, are often found among this fubterraneons wood. Thefe confiderations, joined to proofs drawn from their analyfis, make this opinion more than probable:7 nor are we Angular in maintaining it, as it is adopted by many able modern chemifts. The analyfis of amber, above defcribed, may.fefve as a general fpecimen of the decompofition of other bitu¬ mens : with this fingle difference, that amber is the only one among them which yields the volatile fait aforefaid; and this determined us to examine it preferably to any o- ther. As for the reft, they all yield a phlegm, an acid liquor, and an oil; which is thin at firft, but grows thicker and thicker as the diftillation draws towards an end. It muft be underftood, however, that thefe acids and thefe oils may differ, according to the nature of the bitumens from which they are drawn ; juft as the phlegm, the acid, and the oil, refulting from the decompofition of refins, differ in quantity and quality, according to the nature of the refins from which they are procured. The CHEMISTRY. 161 The principal differences obferved between refins and bitumens are thefe: the latter are lefs foluble in fpirit of v/ine ; have a peculiar fcent, which cannot be accurately defcribed, and of which the fenfe of fmelling only can judge; and their acid is ftronger and more fixed. This Jaft property is one of the motives which induce us to think, that befides the vegetable acid, originally combi¬ ned with the refinous or oily matter now become a bitu¬ men, a certain quantity of mineral acid hath, in a courfe of time,- been fuperadded to conftimte this mixt. We fiiall prefently fee that the f^ft is certainly fo, in the cafe of amber at leaft. The Analyfis of B'ees-wax. Melt the wax you intend to analyfe, and mix with it as.much fine fand as will make it into a ftiff pafte. Put this pafte in little bits into a retort, and diftil as ufual, with a graduated fire, beginning with a very gentle heat. An acid phlegm will come oVer, and be followed by a liquor which at firft will look like an oil, but will foon congeal in the receiver, and have the appearance of a butter or greafe. Continue the diftillation, increafing the fire by infenfible degrees, till nothing more will come off. Then feparate the butterkfrom the acid phlegm in the receiver, mix it with frefh fand, and diftil it again juft as you did the wax before. Some acid phlegm will ftill come off, and an oil will afcend, which will not fix in the receiver, though it be (till thick. Continue the diftillation, with a fire fo governed that the drops may fucceedeach other at the diftauce of fix or feven feconds of time. Do not increafe it, till you perceive the drops fall more flowly ; and then increafe it no more than is neceffary to make the drops follow each other as above direfted. When the diftillation is finifhed, you will find in the receiver the oil come wholly over, and a little a- cid phlegm. Separate the oil from this liquor; and, if you defire to have it more fluid, rediftil it a third time in the fame manner. The Saccharine Juices of Plants analyfed: infanced '' in Honey. Put into a ftone cucurbit the honey'you intend to di¬ ftil ; fet it in a moderate fand-heat, and evaporate the greateft part of its humidity, till you perceive the phlegm to be acid. Then t^ke out the matter remaining in the cucurbit, put it into a retort, leaving a full third thereof empty, and diftil in a reverberatory with degrees of fire. An acid amber-coloured liquor will come over. As the operation advances, this liquor will continually become deeper coloured and more acid, and at the fame time a little black oil will afcend. When the diftillation is over, ' you will find in the retort a pretty large charred mafs, which being burnt in the open air, and lixiviated, affords a fixed alkali. Sugar, manna, and the faccharine juices of fruits and plants, are of the fame nature as honey, yield the fame principles, and in the fame proportions. All thefe fub- ftances muft be confidered as native foaps; becaufe they confift of an oil rendered mifcible with water, by means ef a faline fubftance. They differ from the common ar¬ tificial foaps in" feveral refpe&s,; but chiefly in this, that V-OL * II. No.. 36. 3 their faline part is an acid, whereas that of common foap is an alkali. The natural foaps are not for that reafon the lefs perfect: on‘ the contrary, they diffolve in water without deftroying its tranfparency, and with¬ out giving it a milky colour ; which proves, that acids are not lefs proper than alakalis, or rather that they are more proper additaments, for bringing oils into a fapo- naceous ftate. Gummy Subfances analyfed: injlanced in Gum Arabic. Distil gum arabic in a retort with degrees of fire. A limpid, fcentlefs, and taftelefs phlegm will firft come over ; and then a ruflet coloured acid liquor, a little vo¬ latile alkali, and an oil, which will firft be thin and after¬ wards grow thick. In the retort will be left a good deal of a charred fubftance, which, being burnt and lix¬ iviated, will give a fixed alkali. Gums have at firft fight fome refemblance of refins ; which hath occafioned many refinous matters to be called gums, though very improperly : for they are two diftindt foits of fubftances, of natures abfolutely different frorn each other. It hath been fhewn, that refins have an a- romatic odour ; that they are indiffoluble in water, and foluble in fpirit of wine; that they are only an effential oil grown thick. Gums, on the contrary, have no o- dour, are foluble in water, indiffoluble in fpirit of wine, and, by being analyfed as in the procefs, are converted almoft wholly into a phlegm\and an acid. The fmall portion of oil contained in them is fo thoroughly united with their acid, that it diffolves perfectly in water, and the folution is clear and limpid. In this refpect gums refemble honey, and the other vegetable juices analogous to it. They are all fluid originally ; that is, when they begin to ooze out of their trees. At that time they per- fe&ly refemble mucilages, or rather they are adtual mu¬ cilages, which grow thick and hard in time by the eva¬ poration of a great part of their moifture: juft as refins are true oils, which, lofing their moft fluid parts by e- vaporation, at laft become folid. Infufions or flight de- codtions of mucilaginous plants, when evaporated to dry- nefs, become adhial gums. Some trees abound both in oil and in mucilage : thefe - two fubftances often mix and flow from the tree blended together. Thus they both grow dry and hard together in one mafs, which of courfe is at the fame time both gummy and refinous : and accordingly fuch mixts are named gum reftns. Of Operations on Fermented Vegetable Substances. Of the Produtf of Spiritiwus Fermentation. To make Wine of Vegetable Subfances that are fufccpti- ble of Spirituous Fermentation. Let a liquor fufceptible of, and prepared for, the fpirituous fermentation, be put into a calk. Set this calk in a temperately warm cellar, and cover the bung-hole with a bit of linen cloth only. In more or lefs lime, according to the nature of the liquor to be ferment'd, 2 S aad 16i C H E M and to the degree of heat in the air, the liquor will be¬ gin to fwell, and be rarefied. There will arife an intef- tine motion, attended with a fmall hilling and effervef- cence, throwing up bubbles to the furface, and difchar- ging vapours ; while the grofs, vifcous, and thick parts, being driven up by the fermenting motion, and rendered lighter by little bubbles of air adhering to them, will rife to the top, and there form a kind of foft fjmngy.cruft,-which will cover the liquor all over. The fermenting motion ftill continuing, this cruft will,- from time to time, be lift¬ ed up and cracked by vapours making their efcape through it; but thofe fiffures will prefently clofe again, till, the fermentation gradually going off, and at laft entirely cea- fing, the cruft will fall in pieces to the bottom of the liquor, which will infenfibly grow clear, Then ftcp the calk clofe with its bung, and fet it in a"cooler place. Matters that are fufceptible of the fpirituous fermen¬ tation are feldom fo perfeftly prepared for it by nature as they require to be. If we except the juices.that flow naturally from certain trees, but oftener from incifions made on purpofe in them, all other fubftances require fome previous-preparation. Boerhaave divides the fubftances that are fit for fpi¬ rituous fermentation into five claffes. In the firft he places all the meally feeds, the legumens, and the ker¬ nels of almoft all fruits. The fecond clafs includes the juices of all fruits that do not tend to putrefaftion. In the third clafs ftand the juices of all the parts of-plants which tend rather to acidity than to putrefadlion ; and confequently thofe which yield much volatile alkali are to be excluded. The fourth clafs comprehends the juices or faps that fpontaneoufly diftil from feveral trees and plants, or flow from them when wrounded. He forms his fifth and laft clafs of the faponaceous, Saccha¬ rine, and concrete or thick j uices of vegetables. Refinous or purely gummy matters are excluded, as not being fer¬ mentable. Thefe five claffes may be reduced into two; one com¬ prehending all the juices, and another all the meally parts of vegetables that are fufceptiblp of fermentation. The juices want nothing to fit them for fermentation, but to be exprsffed out of the fubftances containing them, and to be diluted with a Sufficient quantity of water. If they be very thick, the beft way is to add fo much water as (hall render the mixed liquor juft capable of bearing a new-laid egg. With refpeft to farinaceous fubftan- ce?, as they are almoft all either oily or mucilaginous, they require a little more.management. The method of brewing malt liquors will furnifh us with examples of fuch management. See Brewing. Befides the preparations relating chiefly to malt li¬ quors, there are many other things to be obferved rela¬ ting to fpirituous fermentation in general, and to all mat¬ ters fafceptible of that fermentation. For example; all grain? and fruits defigned for that fermentation muft be pcrftfi’v ripe ; for otherwife they will not ferment with¬ out difficulty, and will produce little or no inflammable fpint. Such matters as are too auftere, too acrid, or aftringent, are for the fame reafon unfit for fpirituous fermentation ; as well as thofe which abound too much in oil. ' I S T R Y. In order to make the fermentation Succeed perfeftly, fo as to produce the beft wine that the fermented liquor is capable of affording, it is neceffary to let it ftand quiet without ftirring it, left the cruft that forms on its fur- face fhould be broken to little fragments, and mix with the liquor. This cruft is a kind'of cover, which hinders the {pirituous parts from exhaling as faft as they^are formed. The free accefs of the air is another condition neceffary to fermentation : and for this reafon the veffel that contains the fermenting liquor muft not be clofe flopped ; the bung-hole is only to be covered with a li-’ nen cloth, to hinder dirt and infefls from falling into it. Nor muft the bung-hole be too large, left too much of the fpirituous parts fhould efcape and be loft. Laftly, a juft degree of warmth is one of the condi¬ tions moft neceffary for fermentation : for in very cold weather there is no fermentation at all; and too much heat precipitates it in fuch a manner that the whole li¬ quor becomes turbid, and many fermenting and ferment¬ ed particles are diflipated. If, notwithftanding the exaffeft obfervance of every particular requifite to excite a fuccefsful fermentation, the liquor cannot, without difficulty, be brought to ef- fervefee, which fcarce ever happens but to malt-liquor, it may be accelerated by mixing therewith fome matter that is very fufceptible hf fermentation, or affnally fer¬ menting. Such matters are called ferments. The cruft that forms on the furface of fermenting liquors is a moft efficacious ferment, and on that account very much ufed. It fometimes happens, that there is occafron to check the fermentation excited in the liquor, before it ceafes of itfelf. To effe thus in a mafs for twenty-four hosts. Then pour on it twelve pounds of raip-water, and boil the whole for twelve hours at leaft, ftirring the mixture frequently, and adding from time to time fome hot water, to fupply the place of what evaporates. When you have thus boiled the liquor, let it ftand quiet for fome time, and then pour it off from the fediment at bottom. Filter, and evaporate to the confiftence of a fyfup ; and you have the tirflure of Mars "with tartar. The difpen- fatories generally order an ounce of reftified fpirit of wine to be poured on this'tin&ure, in order to preferve it, and to keep it from growing mouldy, as it is very apt to do. Soluble chalybeated tartar is prepared by mixing four ounces of tartarifed tartar with one pound of the tinfture of Mars with tartar, and evaporating them together in an iron veffel to drynefs; aft * which it is kept in a well flopped phial to prevent its growing moift in the air. [ S T R Y. Cryjlal of Tartar combined with the rtgulin; part of Antimosiy. Stibiated or Emetic .tartar. Pulverise and mix together equal parts of the glafs and of the liver of antimony. Put this mixture, with the fame quantity of pulverifed cream of tartar, in¬ to a veffel capable of containing as much water as will diffolve the cream of tartar. Boil the whole for twelve hours, from time to time adding warm water, to re¬ place what is diflipated by evaporation. Having thus boiled your liquor, filter it while boiling hot; evaporate to drynefs ; and you will have a faline matter, which is emetic tartar. Of the Produfl of Acetous Fermentation. Subfiances fufceptible of the Acetous Fermentation turned into Vinegar. The wine, the cyder, or the malt-liquor, you intend to convert into vinegar, being firft thoroughly mixed with its lees, and with the tartar it may have depoiited, put your liquor into a fat ufed before either for making or for holding vinegar. This veffel muft not be quite full, and the external air muft have accefs to the liquor contained in it. Set it where the air may have a degree of warmth anfwering nearly to the twentieth degree a- bove o in Mr de Reaumur's thermometer. Stir the li¬ quor from time to time. There will arife in it a new fermentative motion, accompanied with heat: its vinous odour will gradually change, and turn to a four fmell, which will become ftronger and ftronger till the fermen¬ tation be finiflied and ceafe of itfelf. Then flop your veffel clofe; the liquor it contains will be found con¬ verted into vinegar. AH fubftances that have undergone the fpirituous fer¬ mentation are capable of being- changed into an acid by pafling through this fecond fermentation, or this fecond ftage of fermentation. Spirituous liquors, fuch as wine, cyder, beer, being expofed to a hot air, grow four in a very (hort time. Nay, thefe liquors, though kept with all poffible care, in very cloff veffels, and in a cool place, degenerate at laft, change their natures, and infenfibly turn four. Thus the produft of fpirituous fermentation naturally and fpontaneoully degenerates to an acid. For this reafon it is of great importance, in making wine, or any other vinous liquor, to ftop the fermenta¬ tion entirely, if you defire the wine (hould contain as much fpirit as polfible. It is even more advantageous to check the fermentation a little before it come to the height than afterwards: becaufe the fermentation, tho’ flackened and in appearance totally ceafed,ftill continues in the veffels; but in a manner fo much the lefs percep¬ tible as it proceeds more flowly. Thus thofe liquors, in which the fermentation is not quite finiflied, but check¬ ed, continue for fome time to gain more fpirit; whereas, on the contrary, they degenerate and gradually turn four, if you let the fpirituous fermentation go on till it be .en-r tirely finiftied. The produflion of the fecond fermentation, which we are now to confider, is an acid of fo much the greater ftren£th*» C H E M ftrength, the Wronger and more generous the fpirituous liquor in which it is excited originally was. The ftrength of this acid, commonly called vinegar, depends likewife in a great meafure on the methods ufed in fer¬ menting the vinous liquor, in order to convert it into vi¬ negar: for if it be fermented in broad, flat veflels, and left to grow four of itfelfl, the fpirituous parts will be diflipated, and the liquor be four indeed, but vapid and effete. The vinegar-makers, to increafe the flrength of their vinegar, ufe certain methods of which they make a my- ftery, keeping them very fecret. However, Mr. Boer- haave give us, from fome authors, the following defcrip- tion of a procefs for making vinegar: “ Take two large oaken vats or hoglheads, and in each of thefe place a wooden grate or hurdle, at the di- ftance of a foot from the bottom. Set the veffel upright, and on the grates place a moderately clofe layer of green twigs, or frelh cuttings of the vine. Then fill up the veffel with the foot-ftalks of grapes, commonly called the rape, to' within a foot of the top of the veflel, which muft be left quite open, “ Having thus prepared the two veffels, pour into them the wine to be converted into vinegar, fo as to fill one of them quite up, and the other but half full. Leave them thus for twenty-four hours, and then fill up the half-filled veffel with liquor from that which is quite full, and which will now in its turn be left only half full. Four and twenty hours afterwards repeat the fame operation, and go on thus, keeping the veflels alternately full and half full during every twenty-four hours, till the vine¬ gar be made. On the fecond or third day there will a- rife, in the half-filled veffel, a fermentative motion, ac¬ companied with a fenfible heat, which will gradually in¬ creafe from day to day. On the contrary, the ferment¬ ing motion is almoit imperceptible in the full veffel; and as the two veflels are alternately full and half full, the fermentation is by that means, in fome meafure, inter¬ rupted, and is only renewed every other day, in each veffel. “ When this motion appears to be entirely ceafed, even in the half-filled veffel, it is a fign that the fer¬ mentation is finiflied; and therefore the vinegar is then to be put into common calks clofe flopped, and kept in a-cool place. “ A greater or lefs degree of warmth accelerates or checks this, as well as the fpirituous fermentation. In France it is finiflied in about fifteen days, during the fum- mer; but if the heat of the air be very great, and ex¬ ceed the twenty-fifth degree of Mr de Reaumur’s ther¬ mometer, the half-filled veffel muft be filled up every twelve hours ; becaufe if the fermentation be not fo checked in that time, it will become fo violent, and the liquor will be fo heated, that marry of the fpirituous parts, on which the ftrength of the vinegar depends, will be diflipated ; fo that nothing will remain, after the fer¬ mentation, but a vapid wafh, four indeed, but effete. The better to prevent the diflipation of the fp'irituous parts, it is a proper and ufual precaution to clofe the mouth of the half-filled veffel, in which the liquor fer¬ ments, with a cover made alfo of oak wood. As to the [ S T R Y. 167 full veflel, it is always left open, that the air may aft freely on the liquor it contains : for it is not liable to the fame inconveniences, becaufe it ferments but very flowly.” The vine-cuttings and grape-flalks, which the vinegar- makers put into their veffels, ferve to increafe the ftrength of the liquor. Thefe matters contain a very manifeft and perceptible acid. They aifo ferve as a ferment; that is, they difpofe the wine to become eager more ex- peditioufly and more vigoroufly. They are the better and the more efficacious for having been once ufed, be¬ caufe they are thereby thoroughly drenched with the fermented acid: and therefore the vinegar-makers lay them by for preparing other vinegar, after wafhing them nimbly in running water, in order to free them from a vifcid oily matter which fettles on them during the fer¬ mentation. This matter muft by all means be removed; becaufe it is difpofed to grow mouldy ahd rot; fo that it cannot but be prejudicial to any liquor in which you put it. As the acetous fermentation differs from the fpirituous in its produftion, fo it doth in many circumftances at¬ tending it. 1. Motion and agitation are not prejudicial to the acetous fermentation, as they are to the fpirituous; on the eontrary, moderate ftirring, provided it be not continual, is of fervice to it. 2. This fermentation is accompanied w^th remarkable heat; whereas the warmth of the fpirituous fermentation is fcarce fenfible, 3. We do not believe there ever was an inftance of the vapour that rifes from a liquor in acetous fermentation proving noxious, and producing either diforders or fudden death, as the vapour of fermenting wine doth. 4. Vinegar de- pofites a vifcid oily matter, as hath juft been obferved, very different from the lees and tartar of win?. Vinegar never depofites any tartar; even though new wine, that hath not yet depofited its tartar, fliould be ufed in ma¬ king it. To concentrate Vinegar ly Frofi. Expose to the air, in frofty weather, the vinegar you; defire to concentrate. Icicles will form in it; but the whole liquor will not freeze. Take out thofe icicles : and if you defire a further concentration of your vinegar ’ by this method, the liquor which did not freeze the firft time muft be expofed to a ftronger froft. More icicles will form therein, which muft likewife be feparated, and kept by themfelves. The liquor which doth not freeze this fecond time will be a very ftrong concentrated; vinegar. Vinegar analyfed by Dijlillation. Into a glafs or ftone cucurbit put the vinegar to be diftilled; fit to it a glafs head; place your alembic in the fand-bath of a diftilling furnace, and lute on a receiver. Apply a very gentle heat at firft. A clear, limpid, light liquor will-rife, and fall in diftinft drops, like water, from the nofe of the alembic. Continue diftrlling this firft liquor, till the vinegar con¬ tained in the cucurbit be diminifhed about a fourth part. Then fhift your receiver, and increafe the fire a little. A clear liquor will ftill come over, but heavier and more 163 C II E M acid than the former. Diftiiin this manner till you hafe •drawn off into your fecond receiver two thirds of the li¬ quor that was left in the cucurbit, A thick matter will now remain, at the bottom of the •ftill: put it into a retort; lute pn a receiver ; fet your retort in a reverberating furnace, and diftil with degrees of fire. There will come over a limpid liquor, very acid and" (harp, yet ponderous, and requiring a great degree of fire to raife it; on which account it makes the receiver , very hot. It hath-a ftrong empyreumatic fmell When the difiillation begins to flacken, increafe your fire. There will rife an oil of a fetid, quick fmell. Atlaft. when no¬ thing more will rife with the (Irongeft fire, break the re¬ tort, and in it you wilj find a black charred matter : burn it, and from the afties lixiviated with water you will obtain a fixed alkali. The Acid of Vinegar combined 'with different Subjlances. The Acid of Vinegar combined 'with Alkaline Subjlances. Foliated Salt of Tartar, or regenerated Tartar. De- compofition of that Salt. Into a glafs cucurbit put fome very pure and well dried fait of tartar ; and pour on it fome good diflilled vine¬ gar, by little and little at a time. An effkrvefcence will arife. . Pour on more vinegar, till you attain the point of faturation. Then fit a head to the cucurbit; fet it in a fand bath; and, having luted on a receiver, diftil with a gentle heat, and very flowly; till nothing remain but a dry matter. On this refiduum drop a little of the fame vinegar;, and if any efFervefcence appears, add more vinegar till you attain the point of faturation, and diftil again "as before. If you obferve no efFervefcence, the operation was rightly performed. It is not eafy to hit the exadt point of faturation in preparing.this neutral fait; becaufe the oily parts, with which the acid of vinegar is loaded, hinder it from aft- ing fo, brilkly and readily as it would do, if it were as pure as the mineral acids: and for this reafon it often happens, that, when we have neatly attained the point of faturation, the addition of an acid makes no fenfible efFervefcence, though the alkali be not yet entirely fa turated ; which deceives the operator, and makes him conclude erroneoufly that he hath attained the true point of faturation. But he eafily perceives his miftake, when, after having feparated from this faline compound all its fuperfluous moifture by diftillation, he drops frefti vinegar upon it: for then the fairs being more concentrated and confe- quently more aftive, produce an efFervefcence, which would not have been fenfible if this laft portion of acid, inftead of coming into immediate contaft with the dned alkali, could not have mixed therewith till difFufed through, and* in a manner fufFocated by that phlegm from which the acid of the vinegar before neutralifed was gra¬ dually feparated by its combining with the alkali ; that phlegm keeping in folution both the netvral fait already formed, and the alkali not yet faturated. And for this reafon it is neceffary to try, after the firft ddiccation of [ S T R Y. this fait, which is called regenerated tartar, whether or no the juft point .of faturation hath been attained. From what hath been faid, concerning the deficcation of this neutral fait, it is plain, that the ufe of it is only to free the fait from the great quantity of fuperfluous moi¬ fture wherein it is diftblved : which proves; 'hat the acid of vinegar, like all other acids diffolved in much water, is feparated from molt of this redundant phlegm by being combined with a fixed alkali. And hence we muft con¬ clude, that the acid of vinegar, contained in regenerated ' tartar deficcated, is vaftly ftronger and more concentrated than it was before. Though the acid of vinegar is freed, by combining with a fixed alkali, from a great quantity of fuperlluous phlegm, yet the oily parts with which it is entangled ftill cleave to it: thefe parts are not feparated from it by its converfion into a neutral fait, but,-without quitting ir, combine alfo with the fixed alkali ; and this gives rege¬ nerated tartar a faponaceous quality, and feveral other peculiar properties Regenerated tartar, when dried, is of a brown co¬ lour. It is femi-volatile ; melts with* a very gentle heat, and then refembles an undtuous liquor ; which* indicates its containing an oil : when caft upon live coals, it flames; and, when diftilled with a ftrong heat, yields an adlual oil ; all which evidently proves the exiftence of that oil. This fait is. Ibluble in fpirit of wine ; a quality which it probably owes alfo to its oil. It requires about fix parts of fpirit of wine to diflblve it ; and the diffolurion fucceeds very well in a matras, with the help of a gentle warmth. If the .fpirit of wine be abftrafted from this fo¬ lution, by diftiling with a fmall fire, it remains at the bottom of the cucurbit, in the form of- a dry fubftance. compofed of leaves lying one upon another ; which hath * procured it the . name of terra foliata tartari, or foliated fait of tartar. It is not abfolutely neceflary that regenerated tartar be dilFolved in fpirit of wine to make the foliated fait; for it may be procured in this form only by evaporating the water in which it is diflolved. Rut the operation fu’cceeds better with fpirit of wine; probably becaufe the fuccefs thereof depends on ufing an exceeding gentle warmth : now fpirit of wine evaporates with much lefs heat than water Regenerated tartar may alfo be cryftallifed. If you defire to have it in this form, combine the acid with the alkali to the point of faturation ; evaporate the liquor flowly to the confiftence of a fyrup, and fet it in a cool place; where it will {hoot into clufters of cryftals lying one upon another like feathers. Vinegar perfe&ly diflblves abforbent matters alfo, and particularly thofe of the animal kingdom ; fuch as corals, crabs eyes, pearls, In order to a dilFolution of fuch matters, you muft pulverife them, put them into'.a ma¬ tras, and pour on them fpirit of vinegar to the depth of four fingers breadth : an efFervefcence will arife : when that is over, fet the mixture to digeft two or three days in a fand-bath ; then decant the liquor, filter it, and e- vaporate it to drynefs with a very gentle heat. The flatter which remains is called fait of coral, of pearls. C H E M of crabs-eyes, See. according to the fubftances diffolved. If, - inftead of evaporating the liquor, a fixed alkali be mixed therewith, the abforbqpt matter, that was dif¬ folved by the acid, will precipitate in the form of a white powder, which is called the magijlery of coral, of pearls, &c. The Acid of Vinegar corrtbined •with copper. Verdegris. Cry flats of Copper This Combination decompounded. Spirit of Verdegris. Into a large matras put verdegris in powder. Pour -on vt diftilled vinegar to the depth of four fingers breadth. Se’ the matras in a moderate fand heat, and leave the wh le in digeftion, (baking it-from time to time. The vi .jar will acquire a very deep blue-green colour. Wntn the liquor is fufficiently coloured, pour it off by inclination. Put fome frefh vinegar into the matras ; digeft as before ; and decant the liquor again when it is furficiently coloured. Proceed in this manner till the vinegar will extradt no more colour. There will remain in the matras a confiderable quantity of undiflblved mat¬ ter. The vinegar thus impregnated with verdegris is called of copper. Mix thefe feveral tindlures, and evaporate them with a gentle heat to a pellicle. Then fet the liquor in a cool place : in the fpace of a few days a great many cryftals of a mod beautiful green colour will (hoot therein, and ftick to the (ides of the veflel. Pour off the liquor from the cryftals; evaporate it again to a pellicle, and fet it by to cryftallife. Continue thefe evaporations and cry- flailifations, till no more cryftals will (hoot in the liquor. Thefe are called cryftals of copper, and are ufed in paint¬ ing, To this combination of the acid of vinegar with copper the, painters and dealers have given them the title of diftilled verdegris. Vefdegris is prepared at Montpellier. To make it they take very clean plates of copper, which they lay, one over another, with hulks of grapes between, and after a certain time take them out. Their furfaces are then covered all over with a very beautiful green cruft, which.is^verdegris. This verdegris is nothing but cop¬ per corroded by the acid of tartar, analogous to the acid of vinegar, which abounds in the wines of Languedoc, and efpecially in the rape, hulks, and ftones of grapes that have a very auftere tafte Verdegris is a fort of ruft of-copper, or copper corroded and opened by the acid of wine, but not yet converted entirely into a neutral fait: for it is not foluble in watfir, nor does it cryftallife. This arifes from its nor being united with a fufficient quantity of acid. The defign of the operation here de- fen'ied is to furnilh the verdegris with the quantity of ac; i equifite to make it a true metallic fait; for which purpofe diftilled vinegar is very tit. 'Cryftals of copper may be obtained, without employing verdegris, by making ufe of copper itfelf diffolved by the acid of vinegar, according to the method prattifed with refpedt to lead as (hall be (hewn hereafter. But verde¬ gris is generally ufed, becaufe it di(Tolve» fooneft ; it be¬ ing a copper already half difiblved by an acid correfpon- dent to that of vinegar Cryftals of copper are decompounded by the a&ion of Vol. II. No.37. * 3 I S T R Y. 169 fire alone, without any additament; becaufe the acid of vinegar adheres but loofely to copper. In order to de¬ compound this fait, and extradt its acid, it muft be put into a retort, and diftilled in a reverberatory furnace with degrees of fire. An inlipid phlegm rifes firft, which is the water retained by the fait in cryftallifing. This phlegm is fucceeded by an acid liquor, which rifes in the form of white vapours that fill the receiver. Towards the end of the diftillation the fire muft be violently urged, in order to raife the ftrongeft and moft fixed acid. At laft there remains in the retort a black matter, which is nothing but copper, that may be reduced by melting it in a crucible with one part of faltpetre and two parts of tartar. A fimilar acid, but more oily, and in a much fmalier quantity, may be obtained from verdegris by di¬ ftillation. The acid, which in this diftillation comes over after the firft phlegm, is an exceeding ftrong and concentrated vinegar. It is known by the title of fpirit of verdegris. The Acid of Vinegar combined •with head. Cerufe. Salt or Sugar of Lead. This Combination decom¬ pounded. Into the glafs head of a cucurbit put thin plates of lead, and fecure them fo that they may not fall out when the head is put upon the cucurbit. Fit on this head to a wide-mouthed, cucurbit containing fome vinegar. Set it in a fand-bath ; lute on a receiver, and diftil with a gentle heat for ten or twrelve hours. Then take off the head : in it you will find the leaden plates covered, and, in a manner, crufted over with a white matter. This being bruftied off with a hare’s foot is what we call ce¬ rufe. The leaden plates thus cleanfed may be employed again for the fame purpofe, till they be wholly converted into cerufe by repeated diftillations. During the opera¬ tion there will come over into the receiver a liquor fome- what turbid and whitifh. This is a diftilled vinegar in which fome lead is diffolved. Reduce a quantity of cerufe into pow'der ; put it into a matras ; pour on it twelve or fifteen times as much di¬ ftilled vinegar ; fet the matras in a fand-bath ; leave the matter in digeftion for a day, (baking it from time to time: then decant your liquor, and keep it apart. Pour frefti vinegar on what is left in the matras, and digeft as before. Proceed thus till you have diffolved one half, or two thirds, of the cerufe. Evaporate to a pellicle the liquors you poured off from the cerufe, and fet them in a cool place. Greyifh cryftals will (hoot therein. Decant the liquor from the cryftals-; evaporate it again to.a pellicle, and fet it by to cryftallife. Proceed thus evaporating and cryftallifing, as long as any cryftals will (hoot. Diffolve your crvftals in diftilled vinegar, and evaporate the folution, which will then (hoot into whiter and purer cryftals. This is the fait, or fugar ■ of lead. Lead is. eafily diffolved by the acid of vinegar. If it be barely expofed to the vapour of that acid, its furface is corroded, and converted into a kind of calx or white rurt, much ufed in painting, and known by the name of cerufe, or •white lead. But this preparation of lead is not combined with a fufficient quantity of acid to convert 2 U it 170 C H E M it into a fait : it is no more than lead divided and opened by the acid of vinegar ; a matter which is to lead what verdegris is to copper. And therefore if you defire to combine cerufe with the quantity of acid neceffary to con-r vert it into a'true neutral fait, you mull treat it in the fame manner as we .did verdegris in order to procure cry? ftais of copper; that is, you mull: diflblve it in diftilled vinegar, as the procefs diredts. The fait of lead is not very white when it firll Ihoots ; and for this reafon it is diffolved again in diftilled vinegar, and cryftaliifed a fecond time. If fait of lead be repeat¬ edly dilfolved in diltilled vinegar, and the liquor evapo¬ rated, it will grew thick ; but Hill cannot be defecated without great difficulty. If the fame operation be oftener repeated, this quality will be thereby more and more in- creafed ; till at laft it will remain on the fire like an oil or melted wax : it coagulates as it cools, and then looks, at firft fight, like a metallic mafs, fomewhat refembling filver. This matter runs with a very gentle heat, almoft as eafily as wax. The fait of lead hath a faccharine tafte, which hath procured it the name alfo of fugar of lead. For this rea¬ fon, when wine begins to turn four, the fure Way to cure it of that difagreeable tafte, is to fubftitute a fweet one which is not difagreeable to the tafte, by mixing there¬ with cerufe, litharge, or fome fuch preparation of lead ; for the acid of the wine diffolves the lead, and therewith forms a fugar of lead, which remains mixed with the Vine, and hath a tafte which, joined with that of the wine, is not unpleafant. But, as lead is one of the moft dangerous poifons we know, this method ought, never to be praftifed ; and whoever ufes fuch a pernicious drug deferves to be moft feverely punifhed. Yet fome thing very like this happens every day, and muft needs have very bad confequences ; while there is nobody to blame, and thofe to whom the thing may prove fatal can have no miftruft of it. Salt of lead may be decompounded by diftillation with¬ out additament. In order to perform this, you muft put the fait of lead into a glafs or (tone retort, leaving a full third thereof empty, and diftil in a reverberating furnace with degrees of fire. A fpirit rifes, which fills the re¬ ceiver with clouds. When nothing more will come over with a fire that makes the retort red-hot, let the veffels cool, and then unlute them. You will find in the re¬ ceiver an a’uftere liquor, which is inflammable ; or, at leaft, an inflammable fpirit may be obtained from it, if about one half thereof be drawn oflt by diftillaticn in a glafs alembic. The retort in which the fait of lead was decompounded contains, at the end of the operation, a blackiffi matter : this is lead, which will refume its me¬ tallic form on being melted in a crucible; becaufe the acid by which it was diflblved, and from which it hath been feparated, being of a very oily nature, hath left in it a fufficient quantity of phlogifton. What is moft remarkable in this decompofitton of fait of lead, is the inflammable fpirit which it yields, though the vinegar which entered into the compofition of the fait feemed to contain none at all. I s T R Y. Of the Putrid Fermentation of Vegetable Sub- fiances. The Put ref action 6f Vegetables. Fill a hogffiead with green plants, and tread them down a little ; or, if the vegetables be dry and hard fub- ftances, divide them into minute parts, and fteep them a little in water to moiften them : then leave them, or the green plants, in the veflel, uncovered and expofed to the open air. By degrees a heat will arife in the center of the veflel, which will continue increafing daily, at laft grow very ftrong, and be communicated to tfie whole mafs. As long as the heat is moderate, the plants will, retain their natural fmell and tafte. As the heat in- creafes, both thefe will gradually alter, and at laft be¬ come very difagreeable, much like thofe of putrid animal fubftances. The plants will then be tender as if they had been boiled ; or even be reduced to a kind of pap, more or lefs liquid according to the quantity of moifture they contained before. Almoft all vegetable matters are fufceptible of putre- fadtion ; but fome of them rot fooner, and others more (lowly. As putrefaction is only a fpecies of fermentation, the efFedt whereof is to change entirely the ftate of the acid, by combining it with a portion of the earth and oil of the mixt, which are fo attenuated that from this union there refults a new faline fubftance in which no acid is difcernible ; which on the contrary hath the properties of an alkali, but rendered volatile ; it is plain, that, the nearer the acid of a plant fet to putrefy is to this (late, the foober will the putrefaClion of that plant be com¬ pleted. Accordingly all plants that contain a volatile, alkali ready formed, or from which it can be obtained by diftillation, are the moft difpofed to putrefaction. Thofe plants, in which the acid is very manifeft and fenfible, are lefs apt to putrefy ; becaufe all their acid muft undergo the change above fpecified. But vegetable matters, whofe acid is entangled and clogged by fe'veral of their other principles, muft be ftill longer elaborated before they can be reduced to the condition into which complete putrefaction brings all vegetables. The earthy and oily parts, in which the acids of thefe fubftances are fheathed, muft be attenuated and divided by a previous fermentation, which, of thofe parts fubtilifed and united with the acid, forms an ardent fpirit, wherein the acid is more perceptible than in the almoft infipid or faccharine juices out of which it is produced. The acid contained in the ardent fpirit muft be ftill further difengaged, before it can enter into the combination of a volatile alkali : confequently the ardent fpirit muft undergo a fort of de- compofition ; its acid muft be rendered more fenfible, and be brought to the fame condition as the acid of plants in which it manifefts all its properties. Hence' it appears that the fpirituous and acetous fer¬ mentations are only preparatives which nature makes ufe of for bringing certain vegetable matters to putrefaction. Thefe fermentations therefore muft be confidered as ad¬ vances: C H E M I vances towards that putrefaflion in which they terminate, or rather as the fir l ftages of putrefaftion itfelf. Putrefied Vegetable Subjiances analyfed. Put the putrefied plants you mean to analyfe into a glafs cucurbit, and fet it in a fand-bath. Fit to it a head ; lute on a receiver ; diftil with a gentle fire, and a limpid fetid liquor will come over. Continue the diftillatjon till the matter contained in the retort be almoft dry. Then unlute your veffels, and keep the liquor you find in the receiver by itfelf. Put the matter remaining in the cucurbit into a retort, and difHl with a graduated heat. There will rife white vapours ; a pretty confi- derable quantity of liquor nearly like that of the former diftillation; a volatile fait in a concrete form ; and a black oil, which towards the end will be very thick. In the retort there will remain a black charred matter, which being burnt in the open air will fall into afhes, from which no fixed alkali can be extracfted. By means of a funnel feparatc your oil from the aque¬ ous liquor. Difiii tms I&fuOV with a gentle heat. You will by this means obtain a volatile fak like that of ani- ’■mals ; of which you may alfo get fome, by the fame means, from the liquor which came over in the firft di- flillation. This analyfis fhews the changes which putrefaftion produces in vegetable matters. Scarce any of their prin¬ ciples are now to be difcerned. They now yield no aromatic liquor ; no eflential oil; no acid ; and confe- •quently no eflential fait, ardent fpirit, or fixed alkali: in a word, whatever their natures were before putrefac¬ tion, they are all alike when they have once undergone this fermentative’motion in its full extent. Nothing can then be obtained from them but phlegm, a volatile alkali, a fetid oil, and an infipid earth. Almpft allthefe changes are owing to the tranfmutation of the acid, which is depraved by putrefadipn, and com- bined with a portion of the oil and fubtilifed earth of the mixt; fo that the refult of their union is a volatile al¬ kali. Now, as the fixed alkali, found in the afltes of unputrefied plants, is only the mbft fixed part of their earth and of their acid, clofely united together by the ig¬ neous motion, it is not furprifing, that, when all the a- dd, with a part of the earth, is ftibtilifed and volatilifed by putrefadion, no fixed alkali can be found in the alhes of putrefied vegetables. The alteration which the acid fuffers by the putrefadive motion is, in our opinion, the g'-eatell it can undergo, without being entirely de- ftroyed and decomppfed,. fo as to be no longer a fait. Of Operations on Animal Substances. Of Mi l k. Milk feparated into Butter, Curd, and Whey : injlanced in Cow’s-Milk, Put new cow’s milk into a flat earthen pan, and fet it in a temperate heat. In ten or twelve hours time there will gather on its furface a thick matter, of a fomewhat' S T R Y. m yellovvifli whit; : this is called cream. Gently Mm off this cream with a fpoon, letting the milk you take* up with it run off. Put all this cream into another vcffe!, and keep it. The milk thus fkimmed will not be quite fo thick as before ; nor will it be of fuch a dead white, but have a little blueifh call. If all the cream be not fepa¬ rated from it, more will gather on its furface after fome time, which mull be taken off as the former. In two or three days the flammed milk will coagulate into a foft mafs called curd, and then it taftes and fmells four. Cut this curd acrofs in feveral places. It will imme¬ diately difcharge a large quantity of ferum. Put the whole into a clean linen cloth; hang it up, and under¬ neath it fet a veffel to receive the ferum as it drops. When the aqueous part hath done dripping, there will remain in the filter a white fubftance fomewhat harder than the curdled milk. This fubffance is called cheefe, and the ferum feparated from it is known by the name of •whey. The milk of animals that feed only on vegetables is, of all animal matters, the leaft removed from the vegeta¬ ble nature. The truth of this will be demonffrated by the experiments we fhall produce by and by, for the fur¬ ther analyfis of milk. Moft chemifts juftly confider milk as of the fune na¬ ture with chyle. Indeed there is great reafon to think, that, except fome fmall differences to be afterwards ta¬ ken notice of, thefe two matters are nearly the fame. They are both of a dead white colour, like that of an emulfion ; which proves that, like emulfions, they con- fift of an oily matter divided, diffufed and fufpended, but not perfedly diffolved, in an aqueous liquor. It is not furprifing that thefe liquors fliould refemble emulfions; for they are produced in the fame marine! and may very juftly be called animal emuljfons. For how are vegetable fubftances converted into chyle and milk in an animal body? They are bruifed, divided, and triturated by maftication and digeftion, as perfeftly, at leaft, as the matters pounded in a mortar to make an e- mulfion ; and muft thereby undergo the fame changes as thofe matters ; that is, their oily parts, being attenuated by thofe motions, muft be mixed with and lodged be¬ tween the aqueous parts, but not diflblved therein • be- caufe they do not, in the bodies of animals, meet with faline matters, fuificiently difentangled and adive, to u- nite intimately with them, and by that means render them foluble in water. Neverthelefs, chyle and milk, though produced in the fame manner as emulfions, and very much refembling them, differ greatly from them in fome refpeds ; owing chiefly to the time they remain in the bodies of animals, their be¬ ing heated while there, the elaborations they undergo therein, and the animal juices commixed with them. New milk hath a mild agreeable tafte, without any fa- line pungency nor hath any chemical* trial difcovered in it either an acid or an nlkali. Yet ir is certain, that the juices of plants, out of which milk is formed, contain many faline matters, and .efpecially-acids: accordingly milk alfo contains the fame; but the acids are fo fheathed and combined, that they are not perceplible. The cafe- 172 CHE M is the iame with all the other liquors intended to confti- tute part of an aniiiul body 5 there i$ no perceptible acid in any of them. Hence it may be iqffrred^ that one of the- 'principal changes'which vegetables .undergo, in order to their be¬ ing converted into an animal fuollance, coniifts in this, that their acids are combined, entangled, and (heathed in (irch a manner, that they become imperceptible, and exert none of their properties. Milk left to itfelf, without the help of diftillation, or any additament whavever, undergoes a fort of decompo- iltioh. It runs into a kind of fpontaneous analyfis ; which doth not indeed reduce it to its firfl principles, yet feparates it into three,diftinCl fubftances, as the pro- cefsfhews; namely, into, cream, or the buttery-fat part, into curd or cheefe, and into ferum or whey: which Ihews. that thofe three fubfhnces of which milk confifts, are only mixed and blended together, but not intimately united. . The frit parts, bein,g the lighted, rife gradually to the fur face of the liquor as they feparate from the reft: and this forms the cream. CrCahi, as lltimmed from ,the furface of milk, is not however the pure buttery or Fat part ; it is ftill mixed with many particles of cheefe and whey, which muft be feparated in order to reduce it into butter. The moft limple, and at the fame time the beft method of effecting this, is daily pradifed by the country people. It confifts -in beating or churning the cream, in a veifel contrived for that purpofe, with the flat fide of a circular piece of wood, in the centfe of which a ftaflr is fixed. One would think that the motion, imprefled one the cream by this iniirument, fhould rather ferve to blend more intimately the particles of butter, cheefe, and whey, of which it con¬ fifts, than to feparate them from each other; as this motion feems perfedlly adapted to divide and attenuate thofe particles. But, if we confi.ler what pafles on this occafion, we Ihall foon perceive that the motion by which "butter is churned is nothing like triture: for churning is no othery properly fpeaking, than a continually repeated compreflion, the effect whereof is to fqueeze out from a- mongft the buttery particles thofe of cheefe and whey mixed therewith ; by which means the particles of butter are brought into contad with each other, unite, and ad¬ here together. Milk, whether fltimmed or no, grows four of itfelf, and curdles in a few days. When it is, newly curdled, the cheefe and whey feem to be united, and to make but one mafs : but thefe two matters feparate fpontaneoufly from each other, with the greateft cafe, and in a very Ihort time. The acidity, which milk naturally contrads in the fpace of a few days, muft be confidered as the effed of a fermenting motion, which difcovers in that liquor an acid that was not perceptible before. This, properly fpeaking, is an acetous fermentation, which milk pafles through m its way to putrefadion ; and it foon follows, efpecially if the milk be expofed to a hot air. If, inftead of leaving milk to grow four and curdle of itfelf, an acid be mixed therewith, while it is yet fweet and newly milked, it immediately coagulates ; which I S T R Y. gives reafdn to think, that its curdling naturally is the effed of the acid, which difcovers itfelf therein as it grows ftale. The-coagulation of milk may alfo be confiderably ac¬ celerated, by fetting it in a fand-bath gently heated"; or by mixing therewith a little of what,' in the language of the dairy, is called rawwi; which is nothing but fome curated and half-digefted milk taken from the ftomach of a calf: or both thefe rftethods may be employed at once, which will produce the effed flill more expsditioufly. It is not difficult to find out the caufe of thefe effeds. The runnet, which is milk already curdled and grown four is an adual ferment to fweet milk, difpofing it to turn four much more readily : for though milk, when thus haftily curdled by the runnet, hath not a manifeftly acid tafte, yet it is certain that this acid begins to exert itfelf. The proof thereof is, that, being expofed to the fame degree of heat with milk equally new, that is not mixed with this feVment, it turns four much Iboner. As to the eff .-d of heat in coagulating milk, there is nothing extraordinary in it: we know how much it promotes' and accelerates all fermentative motion. The whole of this per fed! y agrees with what we faid before concerning fermentation. Fixed alkalis alfo coagulate milk ; but at the fame time they fepafate the whey from the cheefe, which floats on the liquor in cloats. They give the milk a ruffet colour inclining to red; which may arife from their attacking the fat part. The ftparation of milk into butter, cheefe, and whey, is a kind of imperfed analyfis thereof, or rather the be¬ ginning of one. In order to render it complete, we muft examine each of thefe fubftances feparately, and find the principles of which they confift. This we ftxall . endeavour to do in the following procefs. Butter analyfed by Dif iliation. Into a glafs retort put the quantity of frefli butter you intend to diftil. Set the retort in a reverberatory ; apply a receiver ; and let your fire be very gentle at firft. The butter will melt, and there will come over fome drops of clear water, which will have the peculiar fmell of frdh butter, and fhew fome tokens of acidity. If the fire be increafed a. little, the butter will feem to boil : a froth will gather on its furface, and* the phlegm, fttll’ continuing to run, will gradually come to fmelf juft like butter clarefied.in order to be preferved. Its acidity will be ftronger and more manifeft than that of the firft drops that came over. Soon after this, by encreafing the fire a little more, there will rife aq oil, having nearly the fame degree of fluidity as fat oils ; but it will grow thicker as the diffil- lation advances, and at laft will fix in the receiver when it cools. It will bq accompanied with fome drops of li¬ quor, the acidity whereof will always increafe, while its quantity decreafes, as the diftillation advances. While this thick oil is diftilling, the butter contained in the retort, which at firft feemed to boil, will be calm and fmooth, without the leaft appearance of ebullition j though the heaf be then much greater than when it boil¬ ed. Continue the diftiilation, conftantly increafing the fire C H E M fire by degrees as you find it neceflary for the elevation of the thick oil. This oil, or rather this kind of butter, will be St laft of a rufiet colour. There will rife along with it fome white vapours exceeding lharp and pungent. When you obferve that nothing more comes over, though the retort be quite red-hot, let the veflels cool, and unlute them. You will find in the receiver an aque¬ ous acid liquor, a fluid oil, and a kind of fixed browfr butter. Break the retort, and you will find, therein a kind of charred matter ; the furface of which, where it touched the glafs, will be of a fliining black, and have a fine polifh. The analyfis of butter proves, that this fubftance, which is an oily matter in a concrete form, owes its con- fiftence to the acid only, w«fi which the oily part is combined: that is, it follows the general rule frequently mentioned above in treating of other oily compounds ; the confiftence whereof we Ihewed to be fo much the firmer, the more acid they contain. The firft portions of oil that come ov^r in the diftillation of butter are fluid, becaufe a pretty confiderable quantity of acid rofe before them, which, being mixed with the phlegm, gives it the acidity we took notice of. This oil, being freed from its acid, and by that means rendered fluid, rifes firft ; becaufe it is by the fame means rendered lighter. The kind of- butter that comes over afterwards, though it be fixed, is neverthelefs far from having the fame confiftence as it had before diftillation ; becaufe it lofes much of its acid in the operation. This acid is what rifes in the form of white' vapours. Thele vapours are at leaft as pungent and irritating as the ful- phureous acid or volatile alkalis: but their fraell is dif¬ ferent : it hath. a refemblance, or rather is the fame, with that which rifes from butter when it is burnt and browned in an open veflel. But, when concentrated and collefted in chafe veflels, as in the diftillation of butter, they are vaftly ftronger : they irritate the throat fo as to inflame it; they are' exceeding lharp and pun¬ gent to the fmell, and are fo hurtful to the eyes that they quickly inflame, them, as in an ophthaimy, and and make them Ihed abundance of tears. The great vo¬ latility of this acid is entirely owing to a portion of the phlogifton of the butter with which it is ftill combined. We took notice in the procefs, that butter feems to boil with a t^ry moderate heat at the beginning of the diftillation, and that in the courfe of the operation the ebullition ceafes entirely, though the heat be then great¬ ly mcreafed; which is contrary to the general rule. The reafon is, that butter, though a feeraingly homoge¬ neous mafs, contains neverthelefs fome particles of cheefe and whey. The particles of whey, being much the lighted, endeavour, on the firft application of heat, to extricate themfelves from among!! the particles of butter, aad to rife in diftillation. Thus they form the drops of acidulated phlegm which come over at firft, and, in ftrug- gling to get free, lift up the buttery parts, or actually boil, which occafions the ebullition obfervable at the be¬ ginning of the procefs. When they are once feparated, the melted butter remains calm and fmooth, without boil¬ ing. If you want to make it boil, you muft apply a much greater degree of heat; which you cannot do in clofe Vol. II. No. 37. 3 1ST R Y. 173 veflels, without fpoiling the whole operation : becaufe the degree of heat neceflary for that purpofe would force up the butter in fubftance, which would rulh over into the receiver, without any decompofuion. Indeed if the veflels were luted, they would be in danger of burlting. As to the cafeous parts, which are mixed with frefh butter, they alfo feparate at the beginning of the diftil¬ lation when the butter is melted, and gather on its fur- face in a fcum. Thefe particles of cheefe and whey, which are heterogeneous to butter, help to make it fpoii the fooner. And for this reafon, thofe who want to keep butter a long time, without the ufe of fait, melt it, and thereby evaporate the aqueous parts. The lighteft portion of the particles of cheefe rifes to the furface, and is flammed off; the reft remains at the bottom of the veflel, from which the butter is ealily feparated, by de¬ canting it while it is yet fluid. Butter may alfo be diftilled, by incorporating it with fome additament which will yield no principle itfelf, nor retain any of thofe of the butter. It may be diftilled in this manner with the additament of fine fand : the ope¬ ration fucceeds very well, is fooner finilhed, and more eafily conduced. If you defire to convert the butter wholly into oil, you muft take the fixed matter you find in the receiver, and diftil it once more, or oftener, according to the de¬ gree of fluidity you want to give it. The cafe is the fame with this , matter as with all other thick oils, which, the .oftener they are diftilled, grow always the more fluid, becaufe in every diftillation they are feparated from part of the acid, to which alone they owe their confift¬ ence. The Curd of Milk analyfed hy Dijlillation. Into a glafs retort put fome new curd, having firft drained it thoroughly of all its whey, and even fqueezed it in a linen cloth to exprefs all its moifture. Diftil it as you did butter. There will come over at firft an acidu¬ lated phlegm, fmelling like cheefe or whey. As the diftillation advances, the acidity of this phlegm will in- creafe. When it begins to run but very flowly, raife your fire. There will come over a yellow oil, fomewhat em- pyreumatic. Continue the diftillation, ftill increafing the fire by degrees as occafion requires. The oil and a- cid phlegm will continue to rife ; the phlegm growing gradually more acid, and the oil deeper coloured and more empyreumatic. At laft, when the retort is almoft red-hot, there comes off a fecond black oil, of the con¬ fiftence of turpentine, very empyreurfiatic, and fo heavy as to fink in water. In the retort will be left a confi¬ derable quantity of charred matter. Cheefe curd barely drained, till no more whey will drip from it, is not entirely freed thereof; and for this reafon we diredied it to be prefled in a linen cloth, before it be put into the retort to be diftilled. Without this precaution, the remaining whey ulould rife in a con¬ fiderable quantity on the firft application of heat; and, in- ftead of analyfing the curd only, we Ihould at the fame time analyfe the whey alfo. This is tc be u iderft od of green curd and new-made cheefe; - for, if it be fuffered to grow 2 X old. 174 CHE M old, it will at length dry of itfelf: but then we fliould not obtain from it the fame principles by diftillation; as it corrupts and begins to grow putrid after fome time, efpecially if it be not mixed with fome feafoning to pre- ferve it. The firft phlegm that rifes in this diftillation, as in that of butter, is a portion of the whey that was left in the cheefe, notwithftanding its being well preffed. This phlegm grows gradually more acid, being the vehicle of the acids of the cheefe, which are forced up along with it by the fire. The acid obtained from this matter is lefs in quantity, and weaker, than that of butter : and accordingly the oil diftilled from cheefe is not fixed like that of butter. Yet it is remarkable that the laft empyreumatic oil, which is as thick as turpentine, is heavier than water: a property which it probably derives from the quantity of acid it retains. The quantity of charred matter, which remains in the retort after the difiillation of cheefe, is much greater than that left by butter: which proves that the former contains a much greater quantity of earth. Whey anatyfed. Evaporate two or three quarts of whey almoft to drynefs in a balneum marine\ and diftil the extract or re- fiduum in a retort fet in a reverberating furnace, with degrees of.fire, according to the general rule. At firfl fome phlegm will come over ; then a lemon-coloured a- cid fpirit; and afterwards a pretty thick-oil. There will remain in the retort a charred matter, Which being expofed to the air grows moift. Lixiviate it with rain water, and evaporate the lixivium; it will yield you cry- ftals of fea-falt. Dry the charred matter, and burn* it in tire open air with a ftrong fire, till it bfe reduced into allies. A lixivium of thefe alhes will fhew fome tokens of a fixed alkali. It will appear, on examining the three analyfes of the the fubftances whereof milk confifts, that none -of them yields a volatile alkali: which is worthy of notice ; as it is the only animal matter from which fuch a fait can¬ not be obtained. It is true, the milk of animals that feed on vegetables may be confidered as an finter- mediate liquor between vegetable and animal fubftan¬ ces; as an imperfect animal-juice, which- ftill retains much of the vegetable nature: and we actually find, that milk almoft always hath, at leaft in part, the properties of thofe plants with which the animals that yield it are fed. Yet, as it cannot be formed in the body of the animal, without mixing with feveral of its juices that are entirely perfected, and become purely ani¬ mal, it muft appear ftrange that the analyfis thereof fhould not afford the leaft veftige of that principle, which all other animal-matters yield in the greateft plenty. The reafon of this may be found in the ufe to which milk is deftined. It is intended for the nourifhment oi animals of the fame fpecies with thofe. in whofe bodies it is produced. Confequentty it ought as much as pol- fible to referable the juices of the food which is proper fox thofe animals. Now,, as animals that live only on I S T R Y. vegetables could not be properly nourifhed by animal matters, for which nature itfelf hath even given them an averfion, it is not furprifing that the milk of fuch animals fhould be free from any mixture of fuch things as are un- fuitable to the young ones whom it is defigned to nourifh. There is reafon therefore to think, that nature hath dif- pofed the organs in which the feefetion of milk is per¬ formed, fo as to feparate it entirely from all the animal juices firft mixed with it: and this is the principal dif¬ ference between milk and chyle; the latter being necef- farily blended with the faliva, the gaftric and pancreatic juices, the bile and lymph, of the animals in which it is formed. Hence it may be concluded, that, if a quanti¬ ty of chyle could be collefted fufficient to enable us to a- nalyfe it, the analyfis thereof would differ from that of milk, in this chiefly, that it would yield a great deal of volatile alkali, of which milk, as hath been faid,- yields none at all. The fame thing probably takes place in carnivorous animals. It is'certain, that thofe animals chufe to eat the flefh of fuch- Others only as feed upon vegetables; arid that nothing but extreme hunger, and the abfolute want of more agreeable food, will force them to eat the flefh of other carnivorous animals. Wolves, which greedily devour fheep, goats, &c. feldom eat foxes, cats, pole¬ cats, &c. though thefe animals are not ftrong enough to refift them. Foxes, cats, and birds of prey, that make fuch terrible havock among wild-fowl, and other forts of game, do not devour one another. This being laid down, there is reafon to think, that the milk of carnivorous animals is fomething of the nature of t.he flefh of thofe animals that feed on vegetables, and which they chufe to eat, and not of the nature of their own flefh ; as the milk of animals that feed on vegetables is analogous to the juices of vegetables, and when analyfed yields no volatile alkali, though every other part of their body does. But whatever be the nature of milk, and of whatever ingredients it be formed, it always contains the three fe¬ veral fubftances above mentioned; namely, the fat, or buttery part, properly fo called, the cheefy, and the fe- rous part, the laft of which we are now to examine. It is, properly fpeaking, the phlegm of the milk, and con¬ fifts almoft: entirely of water. For this reafon it is pro¬ per to lefFen the quantity thereof confiderably by evapo¬ ration, fo that its other principles, being concentrated and brought nearer together, may become much more fenfible. There is no danger of loftng any effential part of the whey in the evaporation, if it be performed in the balneum maria with fuch a gentle heat as may carry off the aqueous parts only: this greatly ftior- tens the analyfis, which will be exceeding long and tedious if all the, water be diftilled off in clofe vef- fels. As whey is chiefly the aqueous part of milk, as faid above, it rnuft contain all the principles thereof that are foluble in \yater; that is, its faline and faponaceous parts. And accordingly the analyfis thereof ftiews that it contains an oil, rendered perfectly faponaceous by an acid; that is, made perfe&ly mifcible with water. This quality of the oil contained in whey appears from the perfect tranfpareiicy of that liquor, which we know is C H E M the mark of a complete diffolution. In the diftillation of whey, the faponaceous matter contained therein is de- compofed; -the laline part rifes firft, as being the lighted; this is the acid taken notice of in the procefs; after which the oil, now feparated from the principle which rendered it mifcible with water, comes over in its natu¬ ral form, and doth not afterwards mix with the aqueous part. Befides the faponacedus matter, whey contains alfo another faline fubftance; namely, fea falt: this is ob¬ tained by lixiviating the mortuum left in the re¬ tort, which, becaufe of its fixednefs, cannot rife with the other principles in’diftillation. To this fait it is owing that what remains in the retort after diftillation grows moift in the air ; for we know that fea-falt tho¬ roughly, dried hath this property. The fixed alkaline fait, obtained from the caput mor¬ tuum burnt to ailies, proves that milk dill retains fome- thing of the vegetable nature: for the following analyfis will drew us that matters purely animal yield none at all. Of the Subftances- 'which compofe an Animal ' Body. Blood analyfed. Injlanced in Bullock’s Bloody In a balneum 7naria evaporate all the moidure of the blood that the.heat of .boiling water will carry off. There will remain an almod dry matter. Put this dried blood into a glafs retort, and didil with degrees of heat, till nothing more will come over, even when the retort is quite red-hot, and ready to melt. A browniih phlegm ubll rife at fird : this will foon be impregnated with a little volatile alkali, and then will ,come over a yellow oil, a very pungent volatile fpirit, a volatile fait in a concrete form, which will adhere to the fides of the receiver; and, at lad, a black oil, as thick as pitch. There will be left in the retort a charred matter, which being burnt yields no fixed alkali. Blood, which is carried by the circulation into all the parts of the animal body, and furndhes. the matter of all the fecretions, mud be confidered as a liquor confiding of almod all the fluids neceflary to the animal machine: fo that the analyfis thereof is a fort of general though im¬ perfect ahalyfis' of an animal. Blood drawn from the body of an animal, and fet by in a veflel, coagulates as it grows cold; and fomerimes afterwards the coagulum difcharges a yellowifli or lymph ; and in the midfl thereof fwims the red part, which continues curdled. Thefe two fubdances, when analyfed, yield nearly the fame principles; and in that refpedt feem to differ little from each other. Though the feruin of blood be naturally in a fluid form, yet, it hath alfo a' great tendency to coagulate; and a certain degree of heat applied to it, either by water or by a na¬ ked fire, will curdle it. Spirit of wine mixed with this liquor produces on it the fame effeCl as heat. Blood, while circulating in the body of a healthy ani¬ mal, and when newly taken from it, hath a mild tafle, which difcovers nothing like either an acid or an alkali; nor doth_ it '{he# kny fign of either th« one or the other [ S - T R Y. 175 in chemical trials. When taded with attention, it be¬ trays fontething like a favour of fea-falt; becaufe it adually contains a little thereof, which is found in the charred matter left in the retort after the didillation, when carefully examined. We fhewed that milk alfo contains a little of this fait. It enters the bodies of animals with the food they eat, which contains more or lefs thereof according to its na¬ ture. It plainly fuffers no alteration by undergoing the digedions, and palling through the drainers, of the ani¬ mal body. The cafe is the fame with the other neutral falts which have a fixed alkali for their bafis: we find them unchanged in the juices of animals into whofe bodies they have been introduced. They are incapable of com¬ bining, as acids do, with the oilly parts; and fo are diflblved by the aqueous fluids, of which nature makes ufe to free herfelf froifi thofe falts, and difcharge them out of the body. Blood, like all other animal-matters, is, properly fpeak- ing, fufceptible of no fermehtation but that of putrefac¬ tion. Yet it turns fomewhat four before it putrefies. This fmall degree of acetous fermentation is mod fen- fible in flefli; and efpecially in the flefli of young, animals* fuch as calves, lambs, chickens, &c." The -quantity of pure water, which.blood, in its na¬ tural date, contains, is very confiderable, and makes.al¬ mod feven eighths thereof; If it be diddled, without being fird-dried, the operation will be much-longer; becaufe k will be neceflary to draw off all this iniipid phlegm with a gentle fire. There is no reafon to appre¬ hend that, by drying blood in open veffels as directed, any of its other principles will be carried off with its phlegm: for it contains no other fubdance that is vola¬ tile enough to rife with the warmth of a balneum maria. This may be proved by putting fqme. undried blood into- a glafs cucurbit, fitting thereto a head and receiver, and- diddling, in a balneum maria, all that the heat of the bath, not exceeding the heat of boiling water, will raife i for, when nothing more will come over, you will find in the receiver an infipid phlegm only, icarce differing from pure water, except in having a faint fmell like that of blood; wherein it refembles all the phlegms that rife fird in didillation, which always retain fomething of the fmell of the matters from which they were drawn. That part of the blood, which remains in the cucurbit after this fird didillation, being put into a retort, and didd¬ led with a dronger fire, yields exactly the fame prin¬ ciples,. and in the fame proportion, as blood dried in- open veffels in the balneum maria: fo that, if this phlegm of blood contains any principles, the quantity thereof is fo fmall as to be fcarce perceptible. The volatile alkali that rifes with the oil, when blood is diflilled in, a retort with a degree of heat greater than that of boiling water, is either the produ&ion of the fire, pr arifes from the decompofition of an ammoniacal fait of which it made a part. For we fhall fee, when we come to treat of this faline fubdahce, that it is fo extremely volatile as to exceed, in that refpeft, almod all other bodies that we know.: and therefore if this* vo¬ latile alkali pre-exided formerly in the blood, uncom- bined with any other matter capable, in fome meafure, of i76 C H F, M of fixing ir, it Would rife at firlt almoft fpontaneoufly, or at lead on the firft application of the gentled heat. We have an inftance of this in blood, or any other ani¬ mal-matter, that is perfeftly putrefied; whiducontaining a volatile alkali, either formed or extricated by putre- fa&ion, lets go this principle when diftilled, even before the firrt phlegm: and, for this reafon, when putrefied blood is to be analyfed, it mud by no means be dried, like frefh blood, before didillation; for all the volatile alkali would by that means be diflipated and lod at once. Though blood and other animal matters afford no fixed alkali, but, on the contrary, yield much volatile alkali, it doth not therefore follow that all the acid. Which thofe fubdances contained before they were ana¬ lyfed, is employed in the production of a volatile al¬ kali, Flejh analyfed. Infianced in Beef. Into an alembic of retort, placed in a fand-bath, put fome lean beaf, from Which you have carefully feparated all the fat. Didil till nothing more will rife. In this fird didillation a phlegm will come over, weighing at lead half the mafs-of the diddled flefh. In the retort you will find a matter almod dry, which you mud after- ■wavds didil with a naked fire in a reverberating furnace, taking the ufual precautions. There will come over at firft a little phlegm replete with volatile alkali; then a volatile alkali in a dry form* which will dick to the fi'des of theveffel; and alfb a thick oil. After the di- fcillation there will be left in the retort a black,, fhining, light coal. Burn it to afhes in the open air, and lixivi¬ ate thofe afhes: the water of the lixivium will have no alkaline property, but will fhew fome tokens of its con¬ taining a little fearfalt. The flefh of an animal, as appears from the procefs, yields much the fame principles with its blood: and it cannot be* otherwife ; becaufe it is formed altogether of materials furnifhed by the blood. Boner analyfed. Injlanced in Ox-Bones. Gut into pieces the bones of a leg of. beef, carefully feparating all the marrow. Put them into a retort, and didil them in a reverberating furnace as ufual. A phlegm will come over fird; then a volatile fpirit, which will become dronger and dronger ; afterwards a volatile fait in a dry form, with fome oil; and, ladly, a black oil, with a little more volatile fait. There will be left in the retort a charred matter, from which a little fea-fait may be extracted. Reduce this charred matter to afhes, by burning it in the open air. Thefe afhes will give fome flight tokens of a fixed alkali. The analyfis of bones proves, that they confid of the fame principhs with flefh and blood; and the fame may be laid in general of all matters that are truly animal, that actually conditute any part of an animal. Animal Fat Analyfed. ■ Infianced in Mutton-Suet. Put as much mutton-fuet as you pleafe into a glafs retort, only taking care that the veil'd be but half full; and didd with degrees of fire as ufual. A phlegm fmel- I $ T R Y. ling of the fuet will rife fird, and foon grow very add. •After this fome drops of oil will come over, and be fol-* lowed by a matter like oil, in appearance, when it comes over; but it will fix in the receiver, and acquire a con¬ fidence fomewhat fofter than fuet. This kind of butter of fuet will continue to rife to the end of the didillation ; and there will be left in the retort a fmall quantity of charred matter. Eggs analyfed. Injlanced in Pullet's Eggs. Put fome hens eggs in water, and boil them till they be hard. Then feparate the yolks from the whites. Cut the whites into little bits; put them into a glafs cu¬ curbit ; fit on a head and receiver ; didil in a balneum mariee with degrees of fire, raffing it towards the end to the dronged heat which that bath can give; that is, to the heat of boiling water. There will come over an a- queous liquor, or infipid phlegm; the quantity whereof will be very confiderable, feeing it will make about nine tenths of the whole mafs of the whites of the eggs Con¬ tinue your didillation, and keep the water in the bath condantly boiling, till not a drop more of liquor will a- fcend from the alembic. Then unlute your veffels. In the cucurbit you will find your whites of eggs confider- ably flirunk in their bulk. They will look like little bits of brown glafs, and be hard and brittle. Put this refiduum into a glafs retort, and didil, as ufual, in a reverberating furnace with degrees of heat. There will come over a volatile oily fpirit, a yellow oil, a volatile fait in a dry form, and, at lad, a black thick oil. There will be left in the retort a charred matter. Reduce alfo into the fmalled pieces you can the hard yolks of the eggs which you feparated from the whites. Set them in a pan over a gentle fire : dir them with a dick till they turn a little brown, and difcharge a fub- dance like melted marrow. Then put them into a new, drong, canvafs bag, and prefs them between two iron plates well heated'; whereby you will obtain a confider¬ able quantity of a yellow oil Let what remains in the bag be diddled in a retort fet in a reverberating furnace: it will give you the fame principles as you got from the whites. Of the two perfe&ly didindl fubdances that conditute the egg, the yolk contains the embryo of the chick, and is dedined to hatch it : the white is to ferve for thfc nourifhment of the chick when it is formed. Thefe two matters, though they contain the very fame principles, yet differ confiderably from each other; and chiefly in this, that their principles are not in the fame proportions. The white of an egg contains fo much phlegm, that it feems to confid almod totally thereof. All the aqueous liquor, obtained by diddling it in the balneum maria1, is, properly fpeaking, nothing but pure water; for go chemical trial can difeover in it either an acid or a vola¬ tile alkali; or any very perceptilbq oily part. And yet it mud contain fome oil, becaufe the liquor that rifes lad is a little bitterifli to the tafte, and fmells fomewhat of empyreuma. But the principles from which it derives thefe properties are in loo fmall quantities to be didindt- CHEMISTRY. 175 If, inftead of diftilling -the hard white of an egg, with a view to dr6w off the great quantity of water it contains, you'leave it fome time in an air that,is not too dry, the greateft part of its moifture feparates fpontaneoufly, and becomes very fenlible. In all probability-this is the ef-. feft of a beginning putrefa&ion, which attenuates this fubftance, and breaks its contexture. The liquor thus difcharged by the white of an egg thoroughly diffolves the gum-refins, and particularly myrrh. If you defire to diflblve myrrh in this manner, cut a hard-boiled egg,in halves; take out the yolk ; put the powdered gum-refin into the cavity left by the yolk; join the two halves of the white; faften them together with a thread, and hang \ them up in a cellar. In a few days time the myrrh will be diflblved by the moifture that iffues from the white of the egg, and will drop into the veffel placed underneath to receive it. This liquor is improperly called oil ef myrrh per deliquium. All the properties of the whites of eggs, as well as the principles obtained by analyfing them, are the fame with thofe of the lymphatic part of the blood; fo that there is a great refemblance between thefe two fubftances. As to the yolk, it is plain from its analyfis, that pil is the predominant principle thereof. If the yolk of an egg be mixed with water, the oil with' which it is replete, ' and which is by nature very minutely divided, difFufes eafily through the whole liquor, and remains fufpend- ed therein by means of its vifcofity. The liqpor at the fame time becomes milk-white like an emulfion, and is in faft a true animal emulfion. In order to obtain the oil of $ggs by expreffion with the more eafe, care muft be taken to chufe eggs that are feven or eight-days old; bepaufe they are then a little lefs vifcous. Neverthelefs their vifcofity is ftill fo great, that they will not eafily yield their oil by expreflion : and therefore, in Order to attenuate and deftroy entirely this vifcofity, they muft be torrefied before they are put to be prefled. The oil of eggs, like all other oily animal matters, feems analogous to the fat oils of vegetables. It hath all the properties that charadlerife'thofe oils. Its colour is yellow, and it fmells and taftes a little of the empyreuma, occafioned by torrefying the yolks. It is rendered fome- what lefs difagreeable by being expofed to the dew for thirty or forty nights, if care be taken to ftir it often in the mean time. . To conclude: all the principles both in the yolk and the white of an egg are the fame as .thofe found in blood* flefti, and all other matters that are perfectly animal. Of the Excrements of Animals. Dung analyfed. Infianccd in human Excrements. Mr Homberg’s Pkofphorus. Take any quantity you pleafe of human excrement, the cfFeifi; whereof is to change the difpofition of the principles of mixta. With this view he dried forae excrement in the water-bath, and, having pulverifed it, poured thereon-fix times its weight of phlegm that had been feparated from it by diftillation, and put the whole into alargeglafs cucurbit, covered with an inverted vef- feJ that fitted exactly into it, and was clofe luted. This veflel he fet in & balneum marine for fix weeks, keeping up fitch a gentle heat as would not burn one’s hand ; af¬ ter which he uncovered the cucurbit, and having fitted thereto a head and a receiver, diflilled off all the aque¬ ous nioifture in the with a very gentle heat. .. It had now loft almoft all its bad iinell, which was changed into a faint one. It came over fomewhat turbid, whereas it was very clear when pht into the cu- eurhit. Mr Homberg found this water to have a-cofme- tic virtue: he gave fome of it to perfons whofe complexi¬ on, neckv and arms, we re quite fpoiled, being turned brewo, dry, rough, and like a goofe flein: they wafhed with it once a day, and, by continuing the ufe of this water, their fkln became veryToft and white. “ The dry matter leftun the cucurbit after the firft diftillation, had not the leaft fmell of feces: on the con¬ trary, it had an agreeable aromatic odour; and the .vef- fel in which Mr Homberg. had digefted it, being left o- pen in a corner of his laboratory, acquired in time a ftrong fmell of ambergris. It is furprifing, as Mr Hom¬ berg juftly obferves, that digeftion alone ihould change the abominable fmell of excrement ihto an odour as agree¬ able as that of ambergris. This dry matter he powdered coarfely, and put two ounces thereof at once into a glafs retort that would hold about apound’or a pound and a half of water. This he diflilled in a fand-bath with a‘very gentle heat. A fmall quantity of an aqueous liquor came over fiHi, and then an oil as colourlefs as fpring-water. Mr Homberg continued the fame gentle degree of heat till the drops began to come off a little redifh and then he changed the receiver, {topping that which contained the clear oil very ckffe with a cork. Having carried on the diftilla- tion with a fire gradually augmented, there came over a confiderable quantity of red oil; and there remained in the retort a charred matter which burnt very readily.” Theclear oil, without any ill fmell, which Mr Hom¬ berg obtained from the fecal matter by this procefs, was the very thing he was in fearch of, and which he had been affured would convert mercury into fine fixed filver *, yet he ingenucufly owns, that, whatever way he applied -it. he could never produce any change in that metallic fubflancei We (hall now proceed to the other drfeoverks made by Mr Homfeefg on this oceafion. In his attempt to obtain a clear oil from excrement, he diddled it with different additaments, and amongft the red With vitriol and alum. He found that .the matters left in the retort, when he made ufe of thefe falls, be¬ ing expofed to the open air, took fire of themfelves ; that they kindled combudible matters ; in a word, that they were a true phofphorus, of a fpecies different from all then known. Purfuing tbefe'fird hints, he fought and found the means of preparing this plxofghorus by a way [ S T R Y. much more expeditious, certain, and eafy. His procefs is this. “ Take four ounces of feces newly excreted : mix therewith an equal weight of roch-alum eoarfely pow¬ dered : put the whole into a little iron ; an that will hold about a quart of water, and fet it over a gentle Pre un¬ der a chimney. The mixture will melt, and become as liquid as water. Let it boil with a gentle fire, condantly dirring it, breaking it into little crumbs, and feraping off with a fpatula whatever dicks to the bottom or (ides of the pan, till it be perfectly dry. T he pan mud from lime to time be removed from the fire that it may not grow red hot; and the matter mud be dirred, even while it is off the fire, to prevent too much of it from dicking to the pan. When the matter is perfeHly dried, and in little clots, let it cool, and powder it in a metal mortar. Then put it again into the pan, fet it over the fire, and dir it continually. It will again grow a little moid, and adhere together in clots, which mud be con¬ tinually roaded and bruifed till they be perfectly dry ; after which they mud be differed to cool, and then be pulverifed. This powder mud be returned a third time to the pan, fet on the fire, roaded, and perfeHly dried : after which it mud be reduced to a fine powder, and kept in a paper in a dry place. This is the fird or pre¬ paratory operation. ' “ Take two or three drams of this powder. Put it into a little matras, the belly of which will hold an ounce, or an ounce and half of water, and having a neck about fix or feven inches long. Order it fo that your powder ftiail take up no more than about a third part of the matras. Stop the neck of the matras flightly with paper : then take a crucible'four or five inches deep : in the bottom of the crucible put three or four fpoonfJls of fand : fet the matras on this fand, and in the middle of the crucible, fo as not to touch its iides. Then fill up- the crucible with fand, fo that the belly of the matras may be quite buried therein, This done, place your crucible with th: matras in the mid-d of a little earthen furnace, commonly called a Jlove, about eight or ten inches wide above, and fix inches deep from the mouth to the grate. Round the crucible put lighted coals about half way up, and when it hath dood thus half an hour, fill up with coals to the very top of the crucible. Keep up this fire a full half hour longer, or till you fee the infide of the matras begin to be red. Then increafe your fire, by railing your coals above the crucible. Continue this ftrong heat for a full hour, and then let the fire go out. “ At the beginning of this operation denfe fumes will rife out of ihe matras, through the Hopple of paper. Thefe fumes iffae fometimes in fuch abundance as to pufh out the dopple ; which you mud then replace, and dacken the fire. The fumes ceafe when the infide of the matras begins tot grow red ; and then you may increafe the fire without any fear of fpoiling your operation. “ When the crucible is fo cold that it may be fafely taken out of the furnace with one’s hand, you mud gra¬ dually draw the matras out of the fand. that it may cool dowly, and then dop it clofe with a cork. “ If the matter at. the bottom of the matras appear to he C H E M I be in powder when fhaken, it is a fign the .operation hath fucceeded r but if it be in a cake, and doth riot fall into powder on (baking the matras, it (hews that your matter was not fufHciently \roafted and dried in the iron pan du¬ ring the preparatory operation.” Mr Lemeri hath (hewn, that excrement is not the only matter capable of producing this phofphorus with alum ; but that, on the contrary, almoft all animal and even ve¬ getable matters are fit for this combination ; that though Mr Homberg mixed alum in equal quantities only with the fecal matter, it may be ufed in a much greater pro¬ portion^ and, in certain cafes, will fucceed the better ; that, according to the nature of the fubfhmces to be worked on, the quantity of that fait may be more or lefs increafed ; and that whatever is added, more than the dofe requifite for each mat'er, ferve? only to leffen the virtue of the phofphorus, or even deftroys it entirely; that the degree of (ire applied muft be different according to the nature of thofe matters; and, daftly, that falts containing exadtly the fame acid with that 'if alum, or the acid of thofe (alts feparated from its bafis and reduced into fpirit, do not anfwer in the prefent operation : which (hews, fays Mr Lemeri, that many fulphureous matters may be fubftituted for excrement in this operation ; but that there are no falts, or very few, if any, that will fucceed in the place of alum. T his pbofphoru', made either by Mr Homberg’s or by Mr Lemeri’s method, (hints both by day and by night. Befides emitting light, it takes fire foon after it is expofed to the air, and kindles all combuftible matters with which it comes in contadl:; -and this without being rubbed or heated. Meff. Homberg and Lemeri have given the moft pro¬ bable and rhe moft natural explanation of the caufe of the accenfion and other phenomena of this phofphorus. What they fay amounts in fhort to what follows. Alum is known to be a neutral fait, confiding of the vitriolic acid and a calcareous earth. When this fait is calcined with the fecal matter, or other fubftances a- bounding in oil, the volatile principles of thefe fubftances, fuch as their phlegm, their fairs, and their oils, exhale in the fame manner as if they were diftilled ; and there is nothing left in the niatras, when thofe principles are diflipated, but a charred matter, like that which1 is found in retorts wherein fuch mixts have been decompofed by diftdlation. This remainder therefore is nothing but a mixture of alum and charcoal. Now, as the acid of this fait, which is the vitriolic, hath a greater affinity with the phlogifton than with any other fubftance, it will quit its bafis to unite with the phlogifton of the coal, and be converted by that union into a fulphur. And this is the very cafe, of which we have certain proofs in the operation for pre- paiing,this phofphorus; for when, after the volatile principles of the oily matter are drawn off, the fire is increafed, in order to combine cicely together the fixed parts that remain in the matras, thatAs, the alum and the charred matter, we perceive at the mouth of the ma¬ tras a fmall blue fulphureous flame, and a pungent fmell of burning fulphur. Nay, when the operation is finilh- S T II Y. 177 ed, we find a real fulphur (licking in the neck of the ma¬ tras ; and, while the phofphorus is burning, it hath plainly a ftrong fulphureous fmell. It is therefore cer¬ tain, that this phofphorus contains an actual fulphur ; that is, a matter difpofed to take fire with the greateft eafe. But though fulphur be very inflammable, it never takes fire of itfelf, withour being either in contaft with fome matter that is adhrally ignited, or elfe being expofed to a confiderable degree of heat. Let us fee then what may be the caufe of its accenfion, when it is a condiment part of this phofphorus. We mentioned juft now, that the acid of the alum quits its bafis, in order to form a fulphur by combining with the phlogifton of the coal. This bafis we know to be an earth capable of being converted into lime ; and that it is actually converted into quick-lime by the calcination neceffary to produce the phofphorus. We know that new made lime hath the property of uniting with water fo readily, that it thereby contra&s a very great degree of heat. Now when this phofphorus, which is partly conftituted of the bafis of the alum converted into quick¬ lime, is expofed to the air, the lime inftantly attrafls the moifture of which the air is always full, and by this means, probably, grows fo hot as to fire the fulphor with which it is mixed. Perhaps alfo the acid of the alum is not totally changed into fulphur: fome part thereof may be only half-difengaged from its bafis, and in that condition be capable of attrafling ftrongly the hu* midity of the air, of growing very hot likewife by im¬ bibing the moifture, and fo of contributing to the accen-. (ion of the phofphorus. There is alfo room to think that all the phlogifton of the charred matter is not employed inf the produdlioh of fulphur in this phofporus, but that fome part of- it re¬ mains in the ftate of a true coal. The black colour of the unkiridled phofplicrus, and the red fparkles it emits while burning, fufficteridy prove this. Human Urine analyfed. Put fome human urine into a glafs aleriibic; fet it in a water-bath, and diftil till there remain only about a fortieth part of What you put in ; or elfe evaporate the urine in a pan fet in the balneum marine till it be reduced to the fame quantity. With this heat nothing wil! Ex¬ hale but an infipid phlegm, fmejling however like urine; The refiduum will, as the evaporation advances, become of a darker and darker ruffet, and at laft acquire an al- moft black colour. Mingle diis reliduum with thrice its weight of fand, and diftil it in a retort fet in a reverbe¬ rating furnace, with the ufual precautions. At fij-ft there will come over a little more infipid phlegm like the fop- mer. When the matter is almoft dry, a volatile fpirit will rife. After this fpirit, white vapours will appear on increafing the fire ; a yeHow oily liquor will eome off, trickling down in veins ; and together with this liquor a concrete volatile fait, which will (lick tq the-fides of the receiver. At laft there will come over a deep-coloured fetid oil. In the retort there will remain a faline earthy refiduum, which being -lixiviated will yield fome fea- falt. 0/ 78 C H E M Of the Volatile Alkali. Volatile Alkalis rettified and depurated. Mix together the fpirit, the volatile fait, the phlegm, and the oil, obtained from any fubltance whatever. Put the whole into a large wide-mouthed glafs body, and thereto fit a head with a larg/ beak. Set this alembic in a water-bath, lute on a receiver, and diftil with a very gentle heat. There will afcend a fpirit ftrqngly impreg¬ nated with volatile alkali, and a volatile fait in a concrete form, which mull be kept by itfelf. Then increafe your heat to the degree of boiling water ; whereupon there will rife a fecond volatile fpirit, fomewhat more ponder¬ ous than the former, with a light oil that will fwim on its furface, and a little concrete volatile fait. Proceed till nothing more will rife with this degree of heat. Keep by itfelf what came over into the-receiver. At the bot¬ tom of the cucurbit you will find a thick fetid oil. Into fuch another diddling vefiel put the fpirit and fait that rofe firft in this diftillation, and diftil them in the balneum tnariar with a heat ftill gentler than before. . A whiter, purer, volatile fait will fublime. Continue the diftillation till an aqueous moifture rife, which will begin to di/Tolve the fait. At the bottom of the VefTel will be left a phlegm, with a little oil floating on it. Keep your fait in a bottle well flopped. Volatile Alkalis combined •with Acids. Sundry Ammo- niacal Salts. Sal Ammoniac. On a volatile fpirit or fait pour gradually any acid whatever. An effervefcence will arife, and be more or lefs violent according to the nature of the acid. Go on adding more acid in the fame manner, till no effervefcence be thereby excited, or at leaft till it be very final!. The liquor will now contain a femi-volatile neutral fait, called an ammoniacal fait; which may be obtained in a dry form by cryftallifing as ufual, or by fubliming it in clofe veflels, after the fuperfluous moifture hath been drawn off. Volatile alkalis have the fame properties with fixed al¬ kalis, fixity only excepted : fo that a volatile alkali muft produce an effervefcence when mixed with acids, and form therewith neutral falls, differing from each other in nothing but the nature of the acid in their compo- fition. It muft be obferved, that the point of faturation js very difficult to hit on this occafion; owing probably to the volatility of the alkali, which, being much lighter than the acid, tends always to poffefs the uppermoft part of the mixture, while the acid finks to the bottom : whence it comes to pafs, /that the lower part of the liquor is fome- times overcharged with acid, while the upper part is ftill very alkaline. But it is moft eligible that the alkali ftiould predominate in the mixture ; becaufe the excefs of this principle eafily flies off while the moifture is eva¬ porating in order to the cryftallifaticn or fublimation of the ammoniacal fait; which being only femi-volatile, re- filts the heat longer, and remains perfedUy neutral. If the vitriolic acid be combined with a volatile alkali, and the mixture diftilled in a retort to draw off the fu- I S T R Y. perfiuous moifture, a liquor comes over into the receiver which fmells ftrong of a fulphureous acid. Now, as the acid of vitriol never becomes fulphureous, but when it is combined with an inflammable matter, this experiment is one of thofe which demonftrate that volatile alkalis contain a very fenfible quantity of inflammable matter. This fame liquor taftes of an ammoniacal fait ^ which proves that it carries up with it fome of the neutral fait contained in the mixture. The reft of this fait, which is called Glauber's feeret fal ammoniac, or vitriolic fal ammoniac, fublimes into the neck of the retort. It is very pungent on the tongue ; it crackles a little when thrown on a red-hot ftiovel, and then flies off in vapours. The ammoniacal fait formed by the acid of nitre ex¬ hibits much the fame phenomena ; but it requires greater care in drying and fubliming it, becaufe it hath the pro¬ perty of detonating all alone, without the addition of any other inflammable matter : and it will infallibly do fo, if too ftrong a fire be applied towards the end of the opera¬ tion, when it begins to be very dry. This property of detonating by itfelf it derives from the inflammable mat¬ ter contained in the volatile alkali which ferves for its ba- fis : and this is another demonftrative proof of the exift- ence of fuch an inflammable matter in the volatile alkali. This fait is called nitrous ammoniacal fait. With the vegetable acids, that of vinegar for inftance, is formed an ammoniacal fait of a lingular nature, and which can fcarce be Brought to a dry form. A volatile alkali, combined to the point of faturation with the acid of fea-falt, forms another neutral fait, which takes a concrete form either by fublimation or cry- ftallifation. The cryftals of this fait are fo very foft and fine, that a parcel of it looks like cotton or wool. This is the fait properly called fal ammoniac. It is of great ufe in chemiftry and in manufaffures ; but that which is daily confumed in great quantities is not made in the manner above mentioned. It would come ex¬ tremely dear, if we had no other way of procuring it, but by forming it thus with the acid of fea-falt and a vo¬ latile alkali. This fait, or at leaft the materials of which it is formed, may be found in the fuliginofities and foots of moft animal, and of fome vegetable fubftances. The greateft part of what we ufe comes from Egypt, where vaft quantities thereof are made. The method of preparing fal ammoniac in Egypt was not known among us till Meff. Lemaire and Granger. Their memoirs inform us, that chimney-foot alone, with¬ out any additament, is the. matter from which they ob¬ tain their fal ammoniac; that thofe chimneys under which nothing is burnt but cow’s-dung, furnilh the beft foot. Six and twenty pounds of that foot yieldvufually fix pounds of fal ammoniac. “ The operation takes up about fifty, or two and fifty hours. The veffels in which they put the foot are bal¬ lons of very thin glafs, terminating in a neck of fifteen or fixteen lines long, qnd an inch in diameter : but they are not all of the fame fize. The leaft contain twelve pounds of foot, and the greateft fifty; but they fill them only three quarters full, in order to leave'room for the fublimation of the fait. “ The furnace, in which they place thefe ballons, • confifts C H E M ranfifls of four walls built in a quadrangular form. The two front-walls are ten, and the lides nine foot long: but they are all five foot high, and ten inches thick. Within the quadrangle formed by thefe( walls., three archqs run lengthwife from end to end thereof, at the diftance of ten inches afunder. The mouth of this fur nace is in the middle of one of its fronts, and of an oval form ; two foot four inches high, and fixteen inches wide. “ The ballons lie in the fpaces between the arches of the furnace, which ferve inltead of a grate to fupport them. Four of them are ufually placed in each inter¬ val ; which makes fixteen for one furnace. They are fee at the diftian'ce of about half a foot from each other, and fecured in their places with brick and earth. But they leave about four inches on the upper part of .the ballon uncovered, with a view to promote the fublima- tion, 3s they alfo do fix inches of the inferior part, that the heat may the better adt on the matters to be fublimed. Things being thus prepared, theyfirft make a fire with draw, which .they continue for an hour. Afterwards they throw in cow’s dung made up in fquare cakes like bricks. (The want of wood in this-country is the reafon that they generally make ufe of this fuel.) Thefe cakes of dung add to the violence of the fire, which they con¬ tinue in this manner for nineteen hours ; after which they increafe it confiderably for fifteen hours more ; and then they flacken it by little and little. “ When the matter Contained in the veflels begins to grow hot, that is, after fik or feven hours baking, it e- mits a very thick and ill-fcented fmoke, which continues for fifteen hours. Four hours after that, the fal ammo¬ niac is obferved to rife in white flowers, which adhere to the it,fide of the neck of the vefiel ; and thofe who have the direction of the operation take care from.time to time to pafs an iron rod into the neck of the ballon, in order to preferve a pafiage through the faline vault, for giving vent to fome blueilh vapours, which conftantly ifl’ue out of the veflel during the whole operation.” From this hiftory of the preparation of fal ammoniac it appears, that foot, and particularly the foot of animal matters, either contains abundance of this fait perfedtly formed, and waiting only for fublimation to fepa/^te it therefrom, or at lead that it contains the prpper ma¬ terials for formjng it; and that during the operation, which is a kind of didillation of foot, thefe materials combine together and fublime. We fiiewed, in our analyfis of foot, that this fubdance yields by didillation a great deal of volatile alkali; and this is an ingredient which makes at lead one half,of fal ammoniac. As to the other principle of this fa.lt, the marine acid, this alfo mud needs exid in foot: but it is not fo eafy to conceive how it (hould come there. It is verjf true that vegetable and animal fubdanees, the only ones that produce foot in burning, contain fome portion of fea-falt: but then this fait is very fixed, and feems unfit to rife with the acid, the oil, and the -fubtile earth, of which the volatile alkali is formed. .Therefore we mud fuppofe either that its elevation is .procured by the force of the fire, aided by the volatility Vol. II. No. 3,7. 3 I S T R Y. 179 of the matters that exhale in burning; or that, being decompofed by the violence of the combudioh, its acid alone rifes with-the other principles aberve mentioned. 1 he latter feems probable enough : for though in the common operations of chemiflry the bare force ot fire doth not feem luificient to decompole fea-lalt; yet the example oHea-plants, which, before burning, contain this fait in abundance, and whofe allies contain ficarce any at all, but are replete with its fixed part, that is, with its al¬ kaline bafis, feems to prove, that; when this fait is inti¬ mately mixed with inflammable matters, it may be de- Aroyed by burning 5 fo that its acid lhall defert its bafis, and fly off with the foqt. * Before the exaft method of procuring fal ammoniac was known, it was generally imagined that the manufaq-‘ turers mixed fea-fak, and even urine,-with the foot; becaufe thefe two fubdances contain the principles of which this fait confifts. But,* befides that the contrary now -certainly appears from the above .mentioned me¬ moirs, it hath been fhewn by Mr Duhamel, who hath' publiflied leveral memoirs and experiments concerning the compofition and decompofition of fal ammoniac, from which we have partly taken what we have already faid on this fubjedt; it hath been Ihewn, in the fird of thefe memoirs, that the addition of fea-falt to the foot, from which fal ammoniac is to be extraded, contributes no¬ thing to its produdion, and cannot increafe its quantity. That alone, therefore, which was originally contained in the matters that produced the foot, enters as a prin¬ ciple into the compofition of fal ammoniac. Sal ammoniac is foraetimes found perfedly formed in the neighbourhood of vulcanos. This fait is probably produced from the fuliginofities of vegetable or animal matters confumed by the fire of. the vulcano. Sal ammoniac is often impure, ,,becaufe it carries up with it, in fublimation, fome of the black charred mat¬ ter which ought to be' left at the bottom of the veffel: but it is ealily purified. For-this purpofe you need only diflblfe it in water, filter ihe dilution, then evaporate ana ciydallize-; by which means you will have a very white and very pure fal ammoniac. You may if you pleaie, fublime it again in a cucurbit and blind head, with a ire not too brifk.' Some of k will rife in the form of a light white powder;: called flowers of [al ammoni- cc. Thefe flow'ers are no other than true fal ammoniac, which hath differed no decompofition ; becaufe the bare adion of fire is not capable of feparating the acid and the volatile alkali, of which this neutral fajtconfifls. When you intend to decompofb it, you mud ufe the means to be mentioned hereafter. Though fal Ammoniac be only femi-volatile, ancj re¬ quires a Confiderable heat to fublime it, yet it hath the property of - ers of fal ammoniac, ens veneris, and other fuch de¬ nominations, which it borrows from the matters fubli- n;ed with it. 2Z S.at Ido C H E M Sal Ammoniac decompounded by acids. Into a large tubulated retort put a fmail quantity of fal ammoniac in powder: fet your retort in a furnace, and lute on a large ballon, as in the diftillation of the fr.in¬ king acids of nitre and fea-falt. Through the hole'in your retort pour a quantity of oil of vitriol or fpirit of nitre equal in weight to your fal ammoniac. An ef- fefvefcence will inftantly follow. The mixture will fwell, and difcharge white vapours which will come over into the receiver. Stop the whole in the retort immediately, and let the firft vapours pafs over, together with home drops of liquor, which will diftil without fire. Then put a few coals into the furnace, and continue the diftd- lation with a very gentle heat ; which however muft be increafed little by little till nothing more will c me over. When the operation is finifhed, you will find in the re¬ ceiver a fpirit of fait if you made ufe of oil of vitriol: or an aqua regis, if the fpirit of nitre was employed: and in the retort will be left a faline mafs, which will be ei¬ ther a glauber’s fecret fal ammoniac, or a nitrous fal ammoniac, according to the nature of ’the acid ufed to decompound the fal ammoniac. Sal ammoniac decompounded by fixed Alkalis. Vola- tile fait. The Febrifuge of Sylvius. Into a glafs alembic or retort put fal ammoniac and fait of tartar pulverifed and mixed together in equal quantities. Set your veflel in a proper furnace, and im¬ mediately lute on a large receiver. A little volatile fpi¬ rit will afcend ; and a volatile alkali, in a concrete form, very white and beautiful, will fublime into the head, and come over into the receiver, in quantity near two thirds or three fourths of the fal ammoniac ufed. Continue the di ft illation, increafing the fire by degrees till nothing more will fublime. Then unlute the vefiels. Put up your volatile fait immediately into a wide mouthed bottle, and flop it clofe with a eryftal ftopple. At the bottom of the retort or cucurbit you will find a faline mafs, which, being diffolved and cryftallifed, will form a fait nearly cubical, having the tafte and other properties of fea-falt. This is the fal febrifugum filvii. Sal Ammoniac decompounded by abfqrbent Earths and Lime. Fixed Sal Ammoniac. Let one part of fal ammoniac and three parts of lime I S T R Y. flaked in the air be pulverifed feparately, and exnediti- oufiy mixed together. Put this mixture immediately into a glafs retoit, fo large tnat half of it may remain empty. Apply thereto a capacious receiver, with a ft nail hole in it to give vent to. the vapours, if needful. Let your retort ftand in the furnace about a quarter of an hour, without any fire under it. While it ftands thus, a great quantity of invifible vapours wid rife, condenle into drops, and form liquor in the receiver. *Then put two or three live coals-in your furnace, and gradually increafe the fire till no more liquor will rife. Now un¬ lute your veflels, taking all poftible care to avoid the va¬ pours, and quickly pour the liquor out of the receiver into a bottle, which you muft flop with a cryftal rtopple, rubbed with emery. There will remain, at the bottom of the retort, a white mafs, confifting of the lime em¬ ployed in the diftillation, together wit the acid of the fal ammoniac: this is called fixed fal ammoniac. Volatile Alkalis combined 'with oily matters. A Vo¬ latile Oily Aromatic fait. Pulverise and mix together equal parts of fal am¬ moniac and fait of tartar : put the mixture into a gl'afa or ftone cucurbit: pour on it good fpirit of wine till it rife half an inch above the matter. Mix the whole with: a wooden fpatula ; apply a head and a receiver, and di- llil in a land-bath, gently heated, for two or three hours. A Volatile fait will rife into the head ; and then the fpirit of wine will diftil into 'the receiver, carrying with it a portion of the volatile fait. When nothing more will come over, let your velfela cool ; then unlute them, feparate the volatile fait, and \veigh it diretfly. Return it into a glafs cucurbit, and for every ounce thereof add a dram and a half of elfen- tial oil, drawn from one or more forts of aromatic plants. Stir the whole with a wooden fpatula, that the eflence may incorporate thoroughly with the volatile fait. Cover the cucurbit with a head, fit on a receiver, and, having luted it exaftly, diftil in a fand-bath, as before, with a very gende heat. All the volatile fait will riie,. and ftick to the head. Let the fire go opt, and when the veflels are cooled take your fait out af the head. It will have an odour compounded of its own proper fmell, and the fmelf of the efience with which it is com¬ bined. This is an aromatic oily fait. Put it into a bottle flopped clofe with a cryftal ftopple. A TABLE, CHE ( CHEMOSIS, a difeafe of the eyes, proceeding from an inflammation, when the wh te of the eye iweils above the black, and overtops it to fuch a degree, that there appears a fort of gap between them. Others define it to be an elevation of the membrane which furrounds the eye, and is called the white ; be¬ ing an afTeflion of the eye, like white fklh. CHENOPODIUM, in botany, a genus of the pentan- dria digynia clafs. The calix confifts of five leaves ; it has no corolla ; and there is but one lenticular feed. There are 18 fpecies, 13 of which are natives of Bri¬ tain, viz. the bonus henricus, common Englilh mcr cury, or all-good ; the urbicum, or upright blite ; the rubrum, or flrarp leaved goofe foot; the murale, com¬ mon goofe-foot, or fow-bane; the hybridum, or maple¬ leaved blite the album, or common orache ; the vi- ride, or green blite ; the ferotinum. or late-flowered biite; the glaucum, or oak leaved blite; the vulva- ria, or {linking orache; the polyfpermum, round¬ leaved blite, or all feed ; the maritimum, fea blite, or white glafs-wort; and the fruticoium, flirub (tone-crop, or glafs-wort. The leaves of the vulvaria, or {linking orache, are faid to be an excellent anti hyfteric. CHEPELIO, an ifland in the bay of Panama, and pro¬ vince of Darien, in South America, fituated about three leagues from the city of Panama, which it fup plies with provifions : W. long. Si0, N lat. 90. CHEPSTOW, a market-town in Monmouthftiire, fi¬ tuated on the river Wye, near its mouth, about ten miles fouth of Monmouth : W. long, a9 40', N. lat. Si° 4°'- CHEQ, or Cherif, the prince of Mecca, who is, as it were, high prieft of the law, and fovereign pontiff of all the Mahometans, of whatever fe<51 or country they be. See Caliph. The grand fignior, fophies, moguls, khans of Tar¬ tary, &c. fetid him yearly prefents, efpecially tapeftry to cover Mahomet’s tomb withal, together with a fumptuous tent for-himfelf, and vaft fums of money to provide for all the pilgrims during the feventeen days of their devotion. CHERBtJRG, a port-town of France, in the province of Normandy, fituated on a bay of the EngHih channel, oppofite to Hampfliire, in England: W. long. i° 40', N. lat. 490 45 CHEREM, in Jewifli antiquity, the fecond and greater fort of excommunication among the Jews. The cherem deprived the excommunicated perfon of almoft all the advantages of civil fociqty : he could have no commerce with any one, could neither buy nor fell, except fuch thing? as were abfolutely neceflary for life ; nor relbrt to the fchools, nor enter the fy- nagogues ; and no one was permitted to eat or drink with him. The fentence of cherem was to be pronounced by ten perfons, or at leaft in the prefence of ten : but the excommunicated perfons might be abfolved by three judges, or e^en by one, provided he were a dottor of the law. The form of this excommunication was loaded with a multitude of curfes and imprecations, taken from different parts of the feripture. 181 ) CHE CliERESOUL, the capital of Curoiflan, in- Afiatic Turky, and the feat of the beglerbeg, or viceroy, of the province : E. long. 450, N. lat. 36°. CilERLERIA, in botany, a genus of the decapdria tri- gynia clafs. The calix confifts of live leaves ; it has five petals lefs than the leaves of the calix, and five bifid neftaria ; the antherte are alternately barren : and the capfule has three cells and as many valves. There is but one fpecies, viz. tiiefedoides, a native of Swit¬ zerland. CHERLESQUIOR, in Turkifli affairs, denotes a lieu¬ tenant-general of the Grand Signior’s armies. CHERMES, in zoology, a genus of infedls belonging to the order of infedta hemiptera. The roftrum is fi- tuate on the breaft ; the feelers are longer than the breaft ; the four wings are defle&ed ; the breaft is gibbous; and the feet are of the jumping kind. There are 17 fpecies, and the trivial names are taken from the plants which they frequent, as the chermes graminis, or grafs-bug ; the chermes ulmi, or elm- bug, uth of Liverpool: W. long. 30, N. lat. *2 ) CHE j;° 1 S'. It is a bifhop’s fee, and gives the title of earl to the prince of Wales. Wi?w-Chester, the capital of a county of the fame name in Penfilvania, in North America, fituated on the river Delawar, fouth of Philadelphia : W. long. 740, N. lat. 40° 15/. Its harbour is fine and capacious, admitting veflels of any burden. CHESTERFIELD, a market-town of Derbyftiire, fif¬ teen miles north of Derby, W. long. i° 25', N. lat. 530 20 . It gives the title of earl to a branch of the noble family of Stanhope. CHEVALER, in the menage, is faid of a horfe when in paffaging upon a walk or trot, his off fore-leg croiTes or overlaps the near fore-leg every fecond mo¬ tion. CHEVALIER, in a general fenfe, fignifies a knight, or horfeman. CHEVAUX DE FRISE, in fortification, a large joift, or piece of timber, about a foot in diameter, and ten or twelve in length, into the fides whereof are driven a great number of wooden pins, about fix foot long, armed with iron points, and crofling one another. See Fortification. CHEVERON, in heraldry. See Chevron. CHEVIL. SccKevil. CHEVIOT, orTiviOT-HiLLS, run from north to fouth through Curriberland, and were formerly the borders or boundaries between England and Scotland, where many a bloody battle has been fought between fhe^two nations, one of which' is recorded in the 'ballad of Chevy chafe.. CHEVISANCE, inlaw, denotes an agreement or com- pofition, as an end or order fet down between a credi¬ tor and his debitor, &c. In our ftitfiues, this word is moft commonly ufed for an unlawful bargain, or contrad. CHEVRON, or Cheveron, in heraldry, one of the honourable ordinaries of a fliield, reprefenting two rafters of an houfe, joined together as they ought to Hand ; it was anciently the form of the prieftefles head attire: fome'fay, it is a fymbol of protedlion; others, of conftancy; others, that it reprefents knights fpears, <&c. It contains the fifth part of the field, and is fi¬ gured as in Plate LV. fig. A chevron is faid to be abafed, when its point does not approach ehe head of the chief, nor reach farther than the middle of the coat; mutilated, when it does not touch the extremes of the coat; cloven, when the upper pieces are taken'off, fo that the "pieces oply touch at one of the angles ; broken, when one branch is feparated into two pieces ; couched, when the point is turned towards one fide of the efcutcheon; divided, when the branches are of feveral metals, or when me¬ tal is oppofed to colour ; inverted, wlpen the point is turned towards the point of the coat, and its branches towards the chief. Per Chevron, in heraldry, is when the field is divided only by two (ingle lines, riling from the two bafe points, and meeting in the point above, as the chevron does. CHEVRONED, C II I ( 183 ) CHI . CHEVRONED, is when the coat is filled with an. e- qual number of chevrons, of colour and metal. CHEVRONEL, a diminutive of chevron, and as fuch only containing half a chevron. CHEVRONNE, or Chevronny, fignifies the dividing of the fhield feverai times chevron-wife. CHEWING-BALLS, a kind of balls made of afa- foetida, liver of antimony, bay-wood, juniper-wood, and pellitory of Spain ; which being dried in the fun, and wrapped in a linen-cloth, are tied to the bit of the bridle for the horfe to chew: they create an appetite and it is faid, that balls of Venice treacle may be ufed in the fame manner with good fuccefs. CHIAMPA, the fouth divifion of Cochin-china, a coun¬ try of the Eaft-Indies. CHIAN earth, in pharmacy,-one of the medicinal earths of the ancients, the name of which is preferved in the catalogues of the materia medic^fhut of which nothing more than the name has been known for many ages in thelhops. It is a very denfe and compaft earth, and is fent hither in fmall flat pieces from the ifland oLChios, in which it is found in great plenty at this time. It (lands recommended to us as an aflringent. They tell us, it is the greatefl of all cofmetics, and that it gives a whitenefs and fmoothnefs to the Ikin, and prevents wrinkles, beyond any of the other fubilances that have been celebrated for the fame purpofes. CHI APA, the capital of a province of the fame name in Mexico, fituated about 390 miles ealt of Acapulco : W. long. 98°, N. lat. 160 30'. CHIARASCO, a fortified to\vn of Peidmont in Italy, fituated on the river Tanaro, twenty miles fouth-eaft of Turin, and fubjeifl to the king of Sardinia: E.long. 7° 4S'> N. lat. 4.40 40'. CHIARENZA, a port-town of tll^noith-wefl: coafl of the Morea, oppofite to the ifland Zant, in the Medi¬ terranean, and fubjedt to the Turks: E.long. 21° 15', N. lat 370 35'. CHIAROSCURO, among painters. SccClaro-ob- S C U R O. CHICHESTER, the capital city of Suflex, fituated fifty-two miles fouth-weft of London, and twelve miles call of Portfinouth : W. long, yo', and N. lat. 50° 50'. It is a biftxop’s fee, and fends two members to parliament. New Chichester, a^port-town of Penfilvania, fituated on the river Delawar, below Chefter. See Chesteb{. CHICK, or Chicken, in zoology, denotes the young of the gallinaceous order of birds, efpecially the com¬ mon hen. See Phasianus. Chicken-/';*. See Small-Vox, and Medicine. CHicK-oum/, in botany. See Alsine. CHICKLING /^i*, in botany, a name given to the la- thyrus. See Lathyrus. CHICUITO, or Cuyo, a province of South America, bounded by the province of La Plata on the north- ea(l, and by Chili on the weft. CHIDLEY, or Chimley, a market-town of Devon- ftiire, about eighteen miles north-weft of Exeter: W. long. 40, N. lat. 510. Vol. II. No. 37. 3' CHIEF, a term fignifying the head or principal part-of a thing or perfon. Thus we fay, the chief of a par¬ ty, the chief a family, &c. Chief, in heraldry, is that which takes up al! the upper part of the efcutcheon from fide to fide, and reprefents a man’s head. See Plate LXV. fig. 4. It is to take up juft the th> 1 part of-the efcutcheon, as all other honourable ordinaries do, efpecially if they are alone on the (hield ; but if there be feverai of them, they muft be leflened in proportion to their num- ' ber, and the fame holds when they are cantoned, at¬ tended and bordered upon by fome other figures ; then the painter or engraver may be allowed to bring them into a fmaller compafs, to the end that all that is re- prefented about the ordinaries may appear with fome proportion and fymmetry. Chiefs are very much va¬ ried, for they may be convert, fupported, crenelle , furmounted, abaife, rempli, dentille, engrefle, ca nelle, danche, nebule, fleurdelezee, fieuronne, vair echequete, lozange, burelle, pane, frettc, giror.nc chaperonne, chappe, mantele, emmanche, chaufie veftu or reveftu. See Couvert, Supported, /« Chief, imports fomething borne in the chief part or top of the efcutcheon. Chief lord, the feudal lord, or lord of an honour on whom others depend. CntET-ju/llce of the king's bench and common pleas. See Justice. CHIEFTAIN, denotes the captain, or chief, of any clafs, family, or body of men: thus, the chieftains, or chiefs, of the highland dans, were the principal noblemen or gentlemen of their refpeflive elans. CHIERI, a fortified towfl of Peidmont in Italy, fitua¬ ted eight miles eaft ofTurin: E.long. 7° 45', N.lat. CHILBLAINS, CHILD-feL in medicine. See Pernio. See Midwifery. Child-//>/A 5 CHILDERMAS-^r)’, or Innocent’/-^)-, an anivet- fary held by the church, on the 28th of December, in commemoration of the children at Bethlehem, mafla- cred by order of Herod. CHILI, a province of fouth America, bounded by Peru on the north, by the province of La Plata on the eaft, by Patagonia on the fouth, and by the Pacific ocean on the weft ; lying between 250 and 450 S. lat. and be- . tween 750 and 85° W. long. But fome comprehend Patagonia in Chili, extending it to cape Horn, in 5 70 30' S. lat. CHILIAD, denotes a thoufand of any tilings, ran¬ ged in feverai divifions, each -whereof contains that number. CHILIARCHA, ot Chiliarchus, in antiquity, a mi¬ litary officer, who had the command of a thoufand men. CHILIASTS, in church-hiftbry. See Millen arians. CHILMINAR, Chelminar, or Tchelminar, the mod beautiful piece of archite&ure remaining of all an¬ tiquity, being the ruins of the famous palace of Per- ftpoi-s, to which Alexander the Great, in a drunken fit, fet fire, at the indication of Thais die couitezanr 3 A the CHI ( 184 ) CHI the word comes from the Perfian tchehle minar, that is to fay, forty towers. Don Garcias de Silva Figueroa, Pietro della,Valle, Sir John Chardin, and Le Brun, have been very par¬ ticular in defcribing thefe ruins. There appear, fay they, the remains of near four- fcore columns, the fragments of which are at lead fix feet high ; but there are only nineteen can be called entire, with another detached from the reft, about an hundred and fifty paces : a rock of hard black marble ferves as a foundation to the edifice: the firft plan of the houfe is afcended to by ninety-five fteps, all cut in the rock ; the gate of the palace is about twenty feet wide, with the figure of an elephant on one fide, and that of a rhinoceros on the other, thirty feet high, and , both of poliftied marble : near thefe animals there are two columnsj and not far from thence the figure of a - pegafus. After palling this gate, are found fragments of magnificent columns in white marble, the fmalleft of which are fifteen cubits high, the largeft eighteen, having forty flutings three full inches wide each ; from whence we may judge of their thicknef? and other pro¬ portions. Near the gate is feen an infcription on a fquare piece of black marble, containing about twelve lines; the charafters are of an extraordinary figure, refembling triangles, or pyramids: befides this, there are other infcriptions, the charaflers of which refera¬ ble the Hebrew, Chaldaic, or Syriac; others the A- rabic or Perfian ; and others, in fine, the Greek cha- ra&ers. Dr Hyde, who hath explained the Greek infcription, by fupplying fome words that are effaced, obferves, that the infcriptions are engraved very ne¬ gligently, and perhaps by fome foldiers ; or, if they are the work of an engraver, he thinks that he was from Palmyra,. and confequently that they are in the Phoenician tongue : he adds, that as they are in praife of Alexander, they were probably done in the time of that conqueror. CHILTERN, a chain of chalky hills, running from eaft to weft through Buckinghamlhire. CHIALERA, in geography, a port town of Turky in Europe, fimated at the entrance of the guIph of Ve¬ nice, in the province of Epirus, about thirty-two miles north of the city Corfu, near which are the mountains of Chimaera, which divide Epirus from Theflaly: E. long. 20° 40', and N. lat. 40° 20 . CHIMAY, the name of a great lake, lying in the pro¬ vince of Acham, between the Eaft-Indies and China. CHIMERA, a fabulous monfter, which the poets feign to have the head of a lion, the body* of a goat, and the tail of a dragon; and add, that this odd beaft was killed by Bellerophon. The foundation of the fable was, that in Lycia there was a burning mountain, or vulcano, of this name; that the top of this mountain was feldom without lions, nor the middle, which had very good grafs, without goats ; that lerpents bred at the bottom, which was marfhy • and that Bellerophon rendered the mountain habitable. By a chimera, among the philofophers, is under- ftood a mere creature of the imagination, gompofed of fuch contradiflions and abfurdities as cannot polfibly any where exift but in thought. CHIMES of a clock, a kind of a periodical mufic, pro¬ duced at equal intervals of time, by means of a parti¬ cular apparatus added to a clock. CHIMNEY, in archite&ure, a particular part of a houfe, where the fire is made, having a tube or funnel to car¬ ry away the fmoke. See Archjtecture. CHINA, including Chinefe Tartary, a large empire, fi- tuated between 950 and 135° E. long, and between 2iQ and 550 N. lat. being accounted two thoufand miles in length, and one thoufand five hundred in breadth; it is bounded by Ruffian Tartary on the north, by the Pacific ocean on {he eaft and fouth, and by Tonquin, Tibet, and the territories of Ruffia on the weft. It is ufually divided into fixteen pro¬ vinces, which will be defcribed in their alphabetical order. In thefe provinces there are computed to be one hundred and fifty-five capital cities, one thoufand three hundred and twelve of the fecond rank, two thoufand three hundred and fifty feven fortified towns, and upwards of ten millions of families, which may a- mount to about fifty millions of people. The principal commodities of this country are filk, tea, China ware, Japan-ware, and gold duft; of all which the maritime ftates of Europe import great quantities, fending them lilver in return. CniNA-ro<3/, in pharmacy, a medicinal root, brought both from the Eaft and Weft-Indies, thence diftinguilhed. into oriental and occidental; it is the root of a fpecies of fmilax. See Smilax. ChinA-ivare. See Porcelain. CHINCA, a port-town of Peru, in South America, fi- tuated in an-extenfive valley, on a river of the fame name, about fixty miles fouth of Lima : W. long. 76°, and S. lat. 130. CHIN COUGH, a convulfive kind of cough, which children are chiefly fubjeft to. See Medicine. CHINESE, in general, denotes any thing belonging to' China. See Chjna. It is obferved by fome, that the Chinefe language has no analogy with any other Janguagedn the world : it only confifts of three hundred and thirty words, which are all monofyllables, at leaft they are pro¬ nounced fo fhort that there is no diftinguiftiing above one fyllable or found in them; but the fame word, as pronounced with ftronger or weaker tone, has diffe¬ rent fignifications; accordingly, when the language is accurately fpoke, it makes a fort of mufic, which has a real melody, that conftitutes the effence and diftin- guifhing charadfer of the Chinefe tongue. As to the Chinefe charadfers, they are as Angular as the language; the Chinefe have not, like us, any alphabet, containing the elements, or, as it were, the principles of their words: inftead of an alphabet they ufe a kind of hieroglyphics, whereof they have above eighty thoufand. As the Chinefe pretend to an antiquity both with regard to their nation and arts, far beyond that of any other cation, it will not perhaps be unacceptable to give CHI ( give a fliort view of thefe pretenfions, principally extract¬ ed from their own writers. But, when any thing is quoted from the Chinefe hiftory, it is abfolutely neceiTa- ry to attend, i. To the times purely fabalous and my¬ thological ; 2. To the doubtful and uncertain times; and, 3. To the hiftorical times, when the Chinefe hifto- ry, fupported by indifputable monumems, begins to pro¬ ceed on fure grounds. 1. Some afcribe to Tiene-hoang, a book in eight chap¬ ters, which contains the origin of letters. They add, that the characters ufed by the Sane hoang were natural, without any determinate form, that they were nothing but gold and preciqus Itones. Lieou-jou, author of Ouai-ki,* fays, that Tiene-hoang gave names to the' ten KANE, and to the twelve TCHI, to determine the place of the year: this is meant of the cyclic characters. Tiene-hoang fignifies emperor of heaven. They call him alfo Tiene ling, the intelligent heaven; Tfeejun, the fon who nourifhes and adorns all things; and finally Tchong-tiene-hoang-kune, the fupreme king of the mid¬ dle heaven, /, in coined money, tfuene, and in fluffs, pou, &c. They then-denominated money (as is done Hill) by the name of the reigrfng family. That of Hiene-yuene was one inch feven lines, and weighed twelve tchu, [the tchu is the ,20th part of a and a jo weighs 1200 little grains of millet]. They then ingraved letters on their money (as is ftill done at prefent.) It is for this reafon that vgn tfeg, letters, fignifies alfo a piece of money, which is called likewife kini, and tfueng, and tao. Voi. II. No. 38. 3 Tcho-jong (16th emperor of the 9th period) hearing, at Cane-tcheou, the finging of birds, compoled a mulie of union,- whole harmony penetrated every where, touch¬ ed the intelligent fpirit, and calmed the heart of man, in fuch a manner, that the external fenfes were found, the humours in equilibria, and the life very long. He called this Inufic TJie ouene, that is to fay, temperance, grace, and beauty. But the defign, and in fome fort the only aim of the ancient mufic of the Chinefe, according to their au¬ thors, was the harmony of the virtues, the moderation of the paflions, elegance of manners, and, in a word, e- very thing that can contribute to the perfedfion of a good and wife government, Ac. For they were perfuaded that mufic was capable of working all thefe miracles. It is difficult for us to believe them in this, efpecially when .we confider the mufic which' is at prefent ufed among them. But we appeal to the Greeks, who related as a- ftonifhing efFedts from this agreeable invention, whilft the modern Greeks, like mofl part of the Orientals, have no mufic but a wretched and contemptible mono¬ tony. The 17th king of the 9th period is named Hao-yng. In his time they cut down the branches of trees to kill hearts with. Men were few. Nothing but vaft forefts were every where to be feen, and thefe frightful woods were filled with wild beads. How contradidlory is this, and how incompatible with the times in which this prince is faid to have reigned i The 18th king of the 9th period is called Yeou-t/ao- chi. We have feen in the preceeding period, a prince of the fame name. The Ouai-ki places this king at the beginning of the laft ki, and gives him for fucceflbr Soui- gine. At this rate, nine entire periods, or ki, muft have elapfed before men knew how to build huts, or had the ufe of fire. Lopi follows another method: he has ranged Yeou-tfao-chi and Soui-gine in the preceeding pe¬ riod ; and although the king we are now fpeaking of bears the fame name, he fpeaks of him quite differently. The 19th king of the 9th period is named Tchu'-fiang-. chi. They fay, that he commanded Sfee-kouei to make a kind of guitar with five firings named fg, to remedy the diforders of the univerfe, and preferve every thing that had life. The 20th king of the 9th period is named Yng-khang- chi. In his time, the waters did not flow, the rivers did not purfue their ufual courfe, which occafioned a great number of difeafes. Yne-khang inflituted the dances called Ta-vou (grand dances), with a view to preferve health : for, as Lopi fays, when the body is not in motion, the humours have not a free courfe; matter is amaffed in fome parr, from whence come difeafes, which all proceed from fome ob- ftrudtion. The Chinefe alfo imagine, that a man’s virtues may be known by his manner of touching the lute and draw¬ ing the bow, Ac. Thus the Chinefe make dances as well as mufic have a reference to good government; and the Liki fay, 3 B that C H I that we may judge t)f a reign by the dances which are ufed in it. . / The .21 ft and laft king of the 9th period is named Vou- hoai-cbi; bin they 'relate nothing of this prince which is worthy of notice. 2. This is all that the fabulous times contain. If thefe times cannot enable us to fix the real epocha of various Inventions, (as the Chinefe are fo full of contradidhons about the time of thefe different difcoveries), we fee at leaft from them, that the origin of arts has been much the fame among them as among other nations. We are now come down to Fou-hi, who is confidered by the Chinefe hiftorians as the founder of their monarchy. What they fay of this prince and his fucceffors, has fome more folidity in it than what we have hitherto feen. F 'O U - H I. The Ouai ki, quoted in the Chinefe -annals, thus de- fcribes themanners of mankind in thefe days “ In the beginning, men differed nothing from other animals in their way of life. As they wandered up and down in the woods, and women were in common, it happened that children never knew their fathers, but only their mothers. They abandoned themfelves to lull without fhame, and • had not the leaft idea of the laws of decency. T hey thought of nothing but fleeping and fnoring, and then getting up and yawning. When hunger preffed them, they fought for fomcthing to eat; and when they wefe glutted, they threw the reft away. They eat the very feathers and hair of animals, and drapk their blood. They clothed themfelves with fkins quite hairy. The emperor Fou-hi began by teaching them to make lines for catching fifh, and fnares for taking birds. It was for this, that this prince was named Fou hi-chi. He taught them further to feed domeftic animals, and to fatten them for flaughter ; for which they gave him the firname of Pea-bi-chi.” It feems evident, that the ancient Chinefe had at firft no other habitation than caves, the hollows of rocks, and natural dens. T hey were then infe&ed with a kind of infe£! or reptile called iafig; and when they met, they aiked one another. Are you troubled with iangs ? To this day they make ufe of this expreflion, in afking after any perfon’s health; Ceuii-iang? What difeafe have you ? How do you do ? Vou-iang, I am without iang; that is to fay, I am hearty, in perfect health, without any ailment. It would be fuperfluous to relate here, what the Chi¬ nefe fay, in their annals, of the invention of chara<5ters, and of coua, after what hath been faid by F. Couplet and fo many others on that fubjeft. We fhall only add, that the treatife Hit-fee bears, that, at the beginning nations were governed by means of certain knots which they made on flender cords: that afterwards the faint in¬ troduced writing in their place, to affift the manda¬ rins in performing all their offices, and the people in ex¬ amining their conduft ; and that it was by the fym- bol ' Kouai, that he conduced himfelf in the ex¬ ecution of his work. CHI Lopi, whom we have fo often quoted already, fays, that bou-hi extracted from the fymbol of fix lines every lfiat concerned good government. For example, -- Li gave him the hint of making lines for hunting and (1 thing, and thefe lines were a new occafion of in¬ venting fluffs for garments. Lopi adds, that it is a mif- take to imagine, that, in the times of Fou-hi, they liill ufed cords tied and knotted, and that books were not introduced till under Hoang-ti. Fou-hi taught men to rear the fix domeftic ainimals, not only for food, but alfo for viftims, in the facrinces which they offered to Chine, and to Ki. They pretend that Fou-hi regulated the rites Kiao-ch^ne. Fou-hi alfo inftituted marriage ; before this the inter- courfe of the fexes was indifcriminate ; he fettled the ceremonies with winch marriages were to be contracted, in order to render this great foundation of fociety re- fpeiftable. He commanded the women to wear a differ¬ ent drefs from that of the men, and prohibited a man’s marrying a woman of the fame name, whether a relation or not, a law which is adtually ftill in force. Fou-hi appointed feveral minifters and officers to affift him in the government of the empire. One of thefe officers made the letters, another drew up the calendar, a third built the houfes, a fourth praCtifed medicine, a fifth cultivated the ground, a fixth was the mafter of the woods and waters. They pretend that Fou-hi applied himfelf very much to aftronomy. Tire Tcheou-pi fouane fays, that he di¬ vided the heavens into.degrees. - Lopi takes notice, that properly the heavens have no degrees, but that this term is ufed with relation to the path of the fun in the courfe of a year. The period of fixty years is reckoned due to Fou-hi. The Tfiene-piene fays plainly, that this prince made a calendar to fix the year, and that he is the author of Kia-tfe. The Sane-fene fays the fame thing ; and the Hane-li-tchi fays, that Fou-hi made the firft calendar by the Kia-tfe ; but the Chi-pene afcribes this to Hoang-ti. This is one of thefe contradi&ions fo common in the Chi¬ nefe hiftorians. The fame Fou-hi, they fay, made arms, and ordained puniihments. Thefe arms were of wood, thole of Chin- nong were of ftone,. and Tchi-yeou made fome of metal. Fou-hi drained off the waters, and furrounded the ci¬ ties'with walls. In the mean time, as Chin-nong is e- fteemed the firft who made walls of ftone, we mull fup- pofe that thofe raifed by Fou-hi were only of earth or brick. Fou-hi gave rules to mufic. Thofe who afcribe this fine art to Hoang-ti are deceived (or vice verfa.) Af¬ ter Fou-hi had invented fiffiing, he made a long for the fifhers. It was from his example that Chin nong made one for the labourers. Fou-hi took of the wood of Tong ; he made it hol¬ low; and of it made a kine (a lyre, or what you pieafe to tranflate It) feven feet two inches long; the firings were of filk, to the number of 27 ; he commanded this inftrument to be named Li. Others fay it had but 25 firing?. ( 188 ) .CHI (i firings, others ib, and others only 5 ; (which of them {hall we believe?) Befides, others make this indrument only three,feet fix inches fix lines in length. Fou-hi made this infirument, fay fome, to ward off inchantments, and banilh impurity of heart. He took of the wood of Jang, and made alfo a guitar of 36, or rather of 50 firings. This inftrument ferved to adorn the perfon with virtues, and to regulate the heart, &cc. Laftly, he made a third inftrument of ba¬ ked earth ; after which, fay they, ceremonies and mufic were in high efteem. The money which Fou-hi introduced, was of copper, round within to imitate heaven, and fquare without to rtfemble the earth. He himfelf made trial of many medicinal plants. (This is moft commonly faid of Chin-nong: but it is pretend¬ ed, that Chin-nong finifhed what Fou-hi had begun.) This is ail we read of Fou-hi. Several contradidhons will be remarked in mcft of thefe traditions, efpecially when we come to fee. in the fequcl, that almoft all thefe inventions are afcribed to the- fuccelfors of Fou-hi. From hence may be judged what regard is due to the beginnings of the Chinefe hiftory. We have {{ill fome reigns to examine, before we have done with the fabulous and uncertain times. They fay of Koung-koung, that he employed iron in making hangers and hatchets. They afcribe to Niu oua (who is the Eve of the Chi¬ nefe) feveral inftruments of f.iufic. The inftruments feng and hoang ferved her, fay they, to communicate with the eight winds. By means of kouene, or double flutes, flie united all founds into one, and made concord between the fun, moon, and Itars. This is called f>*r- fett harmony. Niu-oua had a guitar ( Je) of five firings; fhe made another of 50 firings, whofe found was fo af¬ fecting, that it could not be borne ; wherefore fhe redu¬ ced thefe 50 firings to 25, to diminiih its force. The emperor Chin-nong is very famous among the Chinefe, by the great difcoveries which, they fay, he made in medicine, agriculture, and even in the military art, fince they believe, that, in the times of Han, they had a book of this prince on the military art. A fondnefs for the marvellous has made fome fay, that, at three years of age, he knew every thing that concern¬ ed agriculture. The very name Chin-nong, in the Chi¬ nefe language, fignifies, the fpirit of hnjbandry^ Chin- nong took very hard wood, of which he made the coul¬ ter of the plough, and fofter wood of which he made the handle. Be taught men to cultivate the earth. They aicribe to him the invention of wine. He fowed the five kinds of grains on the fouth of Mount Ki, and taught the people to make them their food.,' Chin-nong commanded that they ftior.ld be diligent in gathering the fruits which the earth produced. He taught every thing relative to hemp, to the mulberry tree, and the art of making cloth and fluffs of filk. They owe al¬ fo to Chimnong the potters and the founders art ; othets, however, afcribe pottery to Hoang-ti, and the art of melting metals to Tchi-yeou. Chin-nong invented fairs in the middle of the day. This was the origin of commerce and mutual exchange.' 89 ) CHI He made life of money to facilitate trade. He inftitu- ted fcitivals. Ghin-nong diftinguifhed plants, determined their vari¬ ous properties, and applied them flultully in the cnre of difeafes. They fay, that, in one day, he made trial of 70 kinds of poifons, fpoke of 400 difeafes, and taught. 365 remedies. This makes the fubjeft of a book, intitied, Pouenetfao, which they afcribe to him, and which contains four chapters. Others al¬ ledge, and with reafon, that this book is not ancient. rjThey fay, with as little truth, that Chin-nong made books in graved on fquare plates. Chin-nong commanded Tfiou-ho-ki to commit to wri¬ ting every thing relative to the colour of fick perfons, and what concerned the pulfe, to teach hotv to examine its motions if they were regular andjharmonious, and, for this end, how to feel it from time to time, and acquaint the patient. Chin-nong compofed ballads or fongs on the fertility of the country. He made a very beautiful lyre, and a gui¬ tar adorned with precious ftones, to form the grand har¬ mony, to bridle concupifcence, to elevate virtue to the intelligent fpirit, and bring men back to the celeftial verity. Chin-nong afcended a car drawn by five dragons. He v/as the firfi that me'■ ured the figure of the earth, and determined the four leas. He found 900,060 lys is well, and 850,000 is north and fouth. He divided all this vafi fpace into kingdoms. Among the fucceflbrs of Chin-nong they place Hoang- ti, and the rebel Tchi yeou, whom they make the in¬ ventor of arms of iron, and feveral kinds of puniffunents. Tchi-yeou had the power of raifing mills and darknefs extremely thick. Hoang-ti knew not how to attack and overcome him. He accomplilhed it, however, by forming a car, on which he placed a figure whofe arm of itfelf always turned to the fouth, in,order to point out the four regions. Hoang-ti ufed the lance and buckler. Tchi-yeou ordered fabres, lances, and crofs-bows to be made. They afcribe to Hoang-ti the kia-tfe, or cy¬ cle of 60 years ; or at leal! Ta-nao made it by his di- redlion. The Mandarin Tfang-kiai was charged to compofe hiftory. Yong-tcheng made a fphete which reprelented the celeftial orbs, and difcovered the polar ftar. Li-cheou regulated numbers, and invented an inftru- me*t for computation, like to, or the fame with that which is ftill in ufe in China and India; and of which Martini, in his DecadeS, and la Loubere, in his voyage to Siam, have given us the defign and defcription. Ling-lune, a native of Yuene-yu, in the Weft of Ta- hia, (that is, Khoralfan), took reeds in the valley of Hiai-ki ; he cut two of an equal length, and blew into them : this gave orxafion to the invention of bells. He adjufied twelve of thefe reeds to imitate the fong of fong- hoang, the royal bird, (one of the fabulous birds of the Chinefe). He divided thefe reeds into twelve/a ,• fix ferved to imitate the fong of the male, and fix that of the female.. Finally, this man brought mufic to per- feftion, and explained the order and arrangement of dif¬ ferent founds. By.means of thefe lu-lu, he governed: the CHI ( 190 ) CHI the Khi of the Yne and of Yang, he determined the change of the four feafons, and gave calculations for a- ftronomy, geometry, and arithmetic, Yong yuene, by order, of Hoang-ti, made twelve bells of copper, which correfponded to the moons, and fer- ved to adjuft the five tones, and fix the feafons, &c. fables. Hoang ti invented a kind of diadem or tiara, called Mient. He ordered a blue and yellow robe to be made for himfelf, in imitation of the colours of heaven and earth. Having viewed the bird hoei, and confidered the variety of its colours, as well as thofe of the flowers, he made garments be dyed of different colours, to make a diflindion between the great and fmall, the rich and poor. Nin-fong and Tche-tfiang invented mortars for pound¬ ing rice; kettles or caldrons: they invented the art of building bridges, and of making Ihoes ; they made coffins for the dead; and men reaped great advantages from all thefe inventions. Hoei invented the bow, Y-meou arrows ; Khy-pe invented the drum, which made a noife like thunder, trumpets and horns, which imitated the voice of the dragon.. Kong kou and Hoa-liu, by order of the Emperor Hoang ti, hollowed a tree of which they made a ftiip; of the branches of the fame t:re they made oars; and by this means they were able to penetrate into pla¬ ces which feemed inaccefiiWe, and where men had ne¬ ver .been. For the tranfportation of merchandife by land, they alfo invented chariots under this reign, and trained oxen and horfes to draw them. Hoang-ti alfo turned his thoughts to buildings, and gave models of them. He built a temple, called Me¬ kong, in which he facrificed to Chang-ii, or to the Supreme Being. With a view to facilitate commerce, Hoang-ti flruck money, ca\\e& kine-tao, knife of metal, becaufe dt had the fliape of the blade of a knife Hoang-ti having obferved that men died before the time fixed by nature, of difeafes which* carried them off, he commanded Yu-fou, Ki-pe, and Lei-kong, three fa¬ mous phyficians of thefe times, to affiff him to determine what remedies were proper for each difeafe. Si-ling-chi, the chief confort of that emperor, con¬ tributed on her part to the good of the ftate, and taught the people the art of rearing filk-worms, of fpinning their cods, and making fluffs of them. The Ouai-ki takes notice, that Hoang-ti command¬ ed China to be meafured, and divided into provinces or tcheou. Each tcheou was compofed of ten che, each che was compofed of ten tou, and each tou contained ten/e, or ten cities. Thefe ten/e, or cities, had each fiveTy, or ftreets, &c. The empire of Hoang-ti, which, according to this hiftorian, feems to have been confiderable, extended on eeaft to the fea, on the weft to Khong tong. It was bounded on the fouth byKiang,- and on the north by the country of Hoene-jo. They fay nothing that has any relation to the arts un¬ der the three princes who follow Hoang-ti ; that is to fay, under the reigns of Chao-hao, who reigned 84 years ; of Tchouene-hio, .who reigned 78 years; and of Cao fine, who reigned 70 years. They obferve only, that Chao-hao made them beat the watches with a drum: this fuppofes that they had then fome inftrument for mar¬ king the hours. The Se-ki adds, that this emperor levelled the highways, in order to render the mountains acceflible, and that he cleared the channels of rivers. He made alfo a new kind of mufic, called Ta yuene, to unite men and genii, and reconcile high and low. 3. After having overcome the fatigue of fo many fabu¬ lous traditions,' we now come to the hiftorical times. But before we enter upon them, it will not be improper to make fome reflections which are abfolutely neceflary to fhew how little regard is due to this fort of traditions. Thefe reflections are thought to be fo much the more im¬ portant, as they will help to undeceive a great many people of the miftake they are in about the Chinefe anti- cjuities. The Chinefe monarchy begun by three princes, diftin- guifhed by the title of Sane-hoang, that is to fay the three Augufti. Thefe three Augufti, according to the moft generally received opinion, are Fou hi, Chine-neng, and Hoang-ti. The five emperors, fucceflbrs of the Sane-hoang, are djftinguifiied by the title of Ou-ti, that is to fay, the five emperors. The five emperors are, Chao-hao, Tchouene-hio, Tico, Tao, and Chune. This divifion has been followed by Cong-ngane-coue, the great grandfon of Confucius, in the eighth generation, and one of the moft celebrated writers of the dynafly of Hane. It has been adopted alfo by Hoang-fou-mi, and by moft part of the beft writers. The proofs of this opinion are taken partly from the book Tcheou.li, an ancient record, or ftate of the empire, which many afcjibe to* the famous Tcheou-cong, minifter and brother of Vou-vang, who was the founder of the imperial dynafty of Tcheou, eleven hundred and fome odd years be¬ fore the Chriftian sera; partly from the commentaries of Tfo-kieou-mine on the-Tchune-tfieou of Confucius’s mafter. In thefe works, mention is made of the books, Sane-fene, and Ou-tiene, which, they fay, are the hiftories of the three Hoang, and of the five Ti: now, the two firft chapters of Chou-king, which contain an extract of the hiftories of Yao and of Chune, bore the title of Tiene-yao and Tiene-Chune •, from whence it was concluded, that Yao and Chune were two of the five Ti; confequently Fou-hi, Ching-nong, and Hoang-ti, were what are called the three Hoang; and Chao-hao, Tchouene-hio, Tico, Yao, and Chune, were the fiveTi. Thefe may perhaps be thought but feeble proofs to fupport an hiftorical faCt of this kind; but thofe who are of a contrary opinion, bring nothing to induce us to believe them, rather than Cong-ngane-coue and Hoang- fou mi. Hou-chouang-hou, in a preface before the Tfiene- piene of Kine-gine-chane confefles, that we find in the Tcheou-li, the exiftence of the book of three Hoang, and that of five Ti: but he adds, that we do not find there the names of thefe eight monarchs ; that, under the Tfin, they fpoke of T*ene hoang, ofTi-hoang, and of Gine hoang; that Cong-ngane-coue, in his preface to Chou- CHI ( TOT 5 CHI Cijou-king, gives Fou hi. Chine nong, Hoang-ti, for thethree'Hoang, and that be takes Chao hao, Tchouene- hioi Tio, Yao, and Chune for the five Ti; hot that we inow not on what foundation he does this, fince Con¬ fucius, in the Kia' yu, diiHnguifhes by the title of 77, all the kings after Fou hi. The fame thing is proved by fome paffages of Tfo-chi and of Liu-pou-ouei; from whence they conclude, that Fou-hi, Chine nong, and Hoang ti are not the three Hoang, and that there are no other Hoang but heaven, earth, and mass. Tchine-huene retrenches Hoang-ti from the number of the Sane hoang, and puts in his place ]Sfiu-oua, whom he ranges between Fou-hi and Chine nong. Others ftrike out Niu-oua, and put Tcho-yong in the place of Hoang-ti/ Niu-pua was the filler of Fou hi, and Fou-hi, they fay, reigned 115 years. At what age mull this "princefs have mounted the throne, for they make her fuc- ceed her brother ? The famous Se ma-tfiene, to whom the Chinefe, from their high elleem of him, have given the name of Tai jfs- tong, or father of hijlory, will have Hoang-ti, Tchouene- hio, Cao-fine, Yao, and Chune to be the five Ti; and he gave thefe princes for their predeceflbrs Soui-gine chi, Fou-hi, and Chine nong, Vvho, according to him, were the three Hoang. This opinion, fince his time, has been embraced by feveral other writers, who depended upon his authority more than upon proofs which he could not produce. Confucius fays in his Kia yu, that,the princes who had governed-the empire began at Fou hi to take the name of 77 or Emperor. The fame philofopher fays further, in the treatife Hi-tfee, or commentary upon the Y-king, that anciently Fou hi governed China, that Chine nong fucceeded him, that after them Ho.ng-ti, Yao, and Chune were feated on the throne. From fo decifive a teftimony, Hou-ou-fang, and feveral others with him, have not doubted, that .thefe five princes named by Confucius were the Ou ti, or five emperors. As to the Sane- hoang, they admitted Tiene hoang chi, Ti hoang chi, Gine-hoang chi, as three . chiefs of the people who had governed the empire before Fou-hi. As it is from Tao-fle, that the feveral authors we have now quoted, have borrowed their idea of this chi¬ merical divilion of the eight firft Chinefe emperors, into ' three Hoang and five Ti, it is neceflary to relate what thefe religious think themfelves. They have opinions peculiar to themfelves about thefe firft ages of the mo¬ narchy. They believe, that at the firft there were three Augufti, Sane-hoang; then five emperors, Ou ti; next three kings, Sane-vang; and laftly, five Pa, Ou-pa^ that is to fay, five chiefs of Regulos. This order fo regularly obferved of three and then five, which is repeated twice, Ihews plainly, that all this has no foundation in truth, but that it is a lyftem invent¬ ed at pleafure. Wherefore Tou-chong-chu, who lived under the Hane, explained this in an allegorical manner. The three Hoang were, according to him, the three powers, (heaven, earth, and*man); The five Ti were the five duties (the duties of king and fubjeft, of father and children, of huiband and wife, of elder and younger brothers, of friends); the three Vang were the three Vol. II. No. 38. 3 lights, (fun, moon, and ftar$); finally, the five Pa were the five mountains, four of which are fituated at the four cardinal points of the empire, and the fifth at the centre. Thus Tong-tchong-chu allegorized this this pretended fucceflion of kings. But Lopi, who re¬ lates this explanation, adds, it was not his own. This is a point of criticifm of little importance to us ; let them, if theypleafe, afcribe it to fome other than Tong-tchong- chu ; we have ftill ground to fay, that it came from fome writer who lived in an age not far from that of Tong- tchong-chu. This is enough for our prefent purpofe, fince we fee from hence the little regard they then paid to this divifion, which they.confidered as chimerical. It would be in vain to attempt to reconcile all thefe contra- didlions. All thefe imaginary reigns are in the manner of the Tao-fle, who have darkened the origin of the Chi¬ nefe monarchy by their fables and mythology. The ten Ki or periods are of their inventing; they gave them between two and three millions of years duration. But before thefe ten periods, they place three dynafties, viz. the dynafty of Thiene-hoang-chi, that of Ti-hoang-chi, and finally, that of Gine hoang-chi. If we attend to the; fignification of thefe names, they muft be interpreted thus : the Sovereign of heaven, the Sovereign of earth, the Sovereign of men. We fee from hence, that the al legorical explanatiori of Tong-tchong chu, which made the three Hoang fignify the three powers, that is, hea¬ ven, earth, and man, is not without probability. Thefe three Hoang fucceeded to Pouane-cou, other- wife Hoene tune, die chaos, the origin of the world, which'feveral of the Tao fle take for the firft man, or the firft king who governed China. The dynafty of Thipne hoang-chi had thirteen kings, who reigned, fay they, 18,000 years ; then came the dynafty of Ti-hoang chi, whofe kings, to themumber of eleven, make up a like duration of i8,ooo^years. Finally, to Ti-hoang-chi fucceeded the Gine-hoang-chi, whofe dynafty, compofed of nine kings, furnifties a fpace of 45,600 years. Thefe three fums added, give us pre- cifely 8 i,6'oo years. But if we add to thefe three dy¬ nafties, thofe which are comprehended in each of the ten Ki, and which amount, according to fome calculations, to more than 2 30 ; we (hall find that the pretenfions of the Chinefe very much exceed thofe of the Chaldeans and Egyptians. For if we believe the calculations of va¬ rious authors, from Pouane-cou to the death Of Confu¬ cius, which happened in the year 479 before J. C. there is elapfed 276,000 years, or 2,276,000, or 2-"59,86o, or even 3,276,000 ; or, finally, a famous philofopher in the davs of Song, who had undertaken to determine the period of the duration of the world ; for the fyftem of the de- 3 C ItruCUop CHI ( i; ftm&ion and reproduftlon of worlds was very current, not only in the left of Ju or of the learned, but alfo a- inong the Bonzes, Ho-chang or the religious of Fo, and among the Tao-fTe or followers of Lao-Kiune,- that is to fay, among the three great fefts, who have the moft in¬ fluence in the empire. Tchao-cang tfie eftabliihtd then a great period of 129.000 years, called TCuene, com- pol'ed of twelve equal parts, called /w/’, or con 'tunttions, which were each of 10,800 years. In the firft con- junftion, faid he, heaven was formed by little and little, by the motion which the Tai-ki, or the Supreme Being, iinpreffed upon matter which was formeily at perfeft re!L During the fecond conjunftion, the earth w.ts produced in the lame manner. At the middle of the third con¬ junftion, man and all other beings began to fpring up, in the manner that plants and trees are produced in the iflands, which afterwards preferye their feveral kinds by their feeds. At the middle of the eleventh con¬ junftion, all things fltall be deflroyed, and the world fliali fall back again into its primitive chaos, from whence it fhall not arife till after the twelfth conjunftion is ex¬ pired. It is not difficult at prefent to conceive, that the Tao- fle had invented that prodigious number of reigns before Fou-ht, for no other reafon, but to fill up that interval, which, according to them, had ekpfed from the produc¬ tion of man, to the beginning of the Chinefe monarchy, that is to fay, to the reign of Fou hi. The fame calcu¬ lator determined the half of Yueoe, or of his great pe¬ riod of 129,000, years, at the reign of Yao. Thefe Tao-fle, as was faid already, laid down thefe ten ages or ten Ki as an indifputable principle ; each Ki comprehended feveral dynafties, whofe duration they determined as they thought fit, and as their calculation required: but if they were at liberty to increafe or di- mtnifh the duration of the ten Ki, it was not the fame as to their number, which was in fome fort a fundamen¬ tal principle of their feft, from which they were not al¬ lowed to depart. Some miffionaries, to whom this doctrine of Tao-fle was not unknown, imagined, that they difcerned in thefe ten Ki, the ten generations before Noah ; and.as the writers cited by Lopi, and by Cong-ing-ta, lay, that of thefe ten Ki, fix were before Fou he, and four after him ; thefe fame miflionaries have imagined, that Fou-hi was Enoch It muft be owned, in the mean time, that Tchine-huene and feveral others do not obferve the fame order; that they place Cliine-nong in the ninth Ki, Ho¬ ang ti in the tenth, 6c. By this computation Hoang-ti v aild be Noah, and Fou-hi Methufelah, which contra- d.fts their hypothefis. The opinion which confiders the ten Ki of the Chinefe as the ten generations which preceded "Noah, is very ingenious, and not improbable. Towards the end of the reign of Tcheou, about 300 years before the Chriftian xra, fome Jews travelled into China, who might have made the writings of Mofes known there, and, of con- fequence, the ten generations which preceded the de¬ luge : befides, this knowledge was common to the Chaldear s, who might have penetrated into China before the Jews. >2 ) CHI CHINEY, a city of the Auflrian Netherlands, on the confines of the biffiopric of Liege, about twelve milts fouth-eafl of Namur: E. long. 5°, N. lat. 50° 20'. CHINON, a town of France in the province of the Or¬ ica nois, about twenty three miles fouth-wefl of Tours j E. long. 20', and N. lat. 470 15'. CMO, Chios, X10, or Scio, an Afiatic ifland, lying near the coaft of Ionia, in Natolia or Lefier Afia, a- bout one hundred miles weft of Smyrna. It is called by the Turks Sakifaduci, and is about one hundred miles in circumference; being chiefly inhabited by Chriflians of the Greek church, who are faid to have three hundred churches in the ifland. Chio is alfo the capital of the above ifland, fituated on the eaft coaft : E. long. 27°, and N. lat. 38°. CHIONANTHUS, or snow-drop tree, in botany, a genus of the diandria-monogynia clafs. Thecaiix divi¬ ded into four ovalfegments ; ’and the drupa contains but one feed. Y here are two fpecies, viz. the virginica and zeylonica, both natives of the-Indies. CHIOZZO, or Chioggio, a town on an ifland of the fame name, in the gnlph of Venice, by which there is a paflige into the Lagunes, fituated about twelve miles fouth of the city of Venice. CHIPPENHAM, a borough-town in Wiltfhire, about twenty-two miles north-weft of Salifbury : W. long. 2° 12', and N. lat. 510 25 . It fends two members to parliament. CHIPPING, or Much-Wiccomb, a borough-town of Buckinghamfhire, about ten miles fouth of Ailefbury 1 W. long. 42', and N. lat. 510 35'. It fends two members to parliament. CHIROGRAI'HY, a writing under one’s own hand. CHIROM ANCY, a fpeeies of divination, drawn from the different lines and lineaments of a perfon’s hand ; by which means, it is pretended, the inclinations may be difcovered. CHIKONIA, in botany, a genus of the pentandria monogynia clafs. The corolla is rotated; the piftil- lum declines ; the ftaminx are inferted into the tube of the corolla; the antheras are fpiral; and the peri- carpi ura is bilocular. There are eight fpecies, none of them natives of Britain. CBIRONOMY, in antiquity, the art of reprefenting any paft tranfaftion by the geftures of the body, more- efpeeially by the motions of the hands: this made a part of liberal education; it had the approba¬ tion of Socrates, and was ranked by. Plato among the political virtues. CHIROTONF, among ecclefiaftica! writers, denotes the impofitioh of hands ufed in conferring prieftiy or¬ ders. ' . However, it is proper to remark, that chirotony 0- riginajly was a method of elefting magiftrates, by holding up the hands. CHIRVAN, a province of Perfia, lying on the weftern coaft of the Cafpian fea. CHIRURGERY. See Surgery. CHISLEY-LAND, in agriculture, a foil of a middle nature between fandy and clayey land, with a large admixture of pebbles. CKIS3EL, G H O (i CHISSEL, an inftrufnent ranch uftd in carpentiy, ma- fonry, joinery, fculpture, . avoirdupoife : it mud be inclofed in papers containing one pound each, and produced at the excife-ofhce, to be damped. Upon three days no¬ tice given to the officer of excife, private families may make chocolate for their own ufe, provided no lefs- than half an hundred weight of nuts be made at one time. CHOENIX, a dry. meafure, containing a forty-eighth part of a medimnus, or fix bufiiels. Hence the cele¬ brated proverb of Pythagoras, Super chcenice ne fe¬ el eas. CHOIR, that part of the church or cathedral where choiiiders ling divine fervice : it is feparated from the chancel, where the communion is celebrated ; and alfo from the nave of the church, where the people are placed : the patron is faid to be obliged to repair the choir of the church. CHOLEDOCHUS, ia anatomy. See Vol. i. p 26c CHOLER. See Bile. V CHOLERA morbus, in medicine. See Medicine. CHONDRILLA, in botany, a genus of the fyngenefia; polygamia tequalis clals. The calix is caliculated; the receptacle is naked ; the pappus is Ample, and fur- nilhed with a dipes ; and the fiofeules are numerous. There is but one fpecies, viz. the janesa, a native of Germany. CHONDROPTERYGII, in ichthyology, 'a term for¬ merly applied to the order of iilhes, now called am¬ phibia names by Linnaeus. See Amphifia. CHOPIN, or Chop in e, a liquid meafure, ufed both mr Scotland and France, and equal to half their pint.. See Pint, and Measure. CHORASSAN, a province of Perfia, on the north-ead, adjoining to Ufbec Tartary; this was the ancient Badhia, and the native country of the late Kouli Kan.. CHORD, in geometry, a right line drawn from one part of an arch of a circle to the other. Hence, Chord of an arch is a right line joining the extremes, of that arch. Sec Trigonometry.. ClEORTW^ C H O ( 194 Ch.orbs, or Cords, in mufic, are firings, by the vi¬ bration of which the fenfation of found is excited, and by the divifions of which the feveral degrees of tune are determined. Chord is alfo ufed in mufic for the note or tone to be touched or founded : in this fenfe the fifth is faid'to confift of five Chords or .founds. CHORDAPSUS, in medicine, a difeafe of the inteflines, when to the touch they feel like flretched cords : k is ithe fame with the iliac pafiion. CHORDEE, in medicine and forgery, a fymptom at¬ tending a gonorrhoea, confiding in a violent pain un¬ der the frenum, and along the du though-they have the ceremony of an eledtion. Christians 9/' N. lat 56° 30'. CHRISTMAS, a feftival of the Chriftian church, ob- ferved on the 25th of December, in memory of the nativity of Jefus Chrift. CHRISTOPHER-^fr^, in botany. See Christo¬ ph ori an a. CHRISTOPHERS, or St Christophers, one of the Caribbee iflands, to which Columbus gave his Chri¬ ftian name: W.long. 62°, N. lat. 710 30'. It is about twenty miles long, and feven broad j Vol. II. No. 38. 3 )S ) C H R and has a high mountain in the middle, from whence fome rivulets run down.. Its produce is chiefly fugar, - cotton,’ ginger, and indigo. It is a Britiih colony, and lies about fixty miles weft of Antego. CHRISTOPHORIANA, in botany. See Act;ea. CHROASTACES, in natural hiftory. a genus of pellu¬ cid gems, comprehending all thofe of variable colours, as viewed in different lights; of which kinds are the ' opal and the afteria, or oculus cati. See Opal, and Asteria.. CHROMA, in mufic, a note or charadter of time, ufu- ally termed a quaver. Chroma is alfo a graceful way of finging, or playing with quavers and trilloes. CHROMATIC, in the ancient mufic, the fecond of the three kinds into which the confonant intervals were fubdivided into their concinnous parts. The other two kinds are enharmonic and diatonic. Chromatic, in painting, a term ufed to fignify the colouring, which makes the third part in the art of painting. CHROMIS, in ichthyology. See Sparus. CHRONIC, or Chronical, among phyficians, an ap¬ pellation given to difeafes that continue a long time, in contradiftindlion to thofe that foon terminate, and are called acute. See Medicine. CHRONICLE, in matters of literature, a fpecies or- kind of hiftory, difpofed according to the order of time, and agreeing in moft refpedls with annals. See Annals. Books p/'Chronicles, in the canon of feripture, two facred books, called by the Greeks paralipomena, that is, remains, additions, or fupplements, as containing many circumftances omitted in the other, hiftoricai books. CHRONOGRAM, a fpdeies of falfe wit, confiding in this, that a certain date or epocha is exprefled by numeral letters of one or more verfes: fuch is that which makes the motto of a medal ftruck by Guftavus Adolphus, in 1632. ChrlftVs DVX, ergo trIVMphVs. CHRONOLOGY, the fcience or doftrine of time, in fo far as it regards hiftory, whether civil or ecclefia- ftical. The bufinefs of chronology, is to afeertain and- adjuft the various epochas, aeras, and other periods mentioned in hiftory; fo that the revolutions of em¬ pires and kingdoms, and other remarkable events, may be truly ftated. For the principles of chronology, fee Astronomy, Of the divifion of time. CHRONOMETER, in general, denotes any inftrument or machine, ufed in meafuring time ; fuch are dials, clocks, watches, tic. See Clock, Dial, tic. CHRONOSCOPE, denotes much the fame with chro¬ nometer. See the preceding article. CHROSTASIMA, in natural hiftory, a genus of pel¬ lucid gems, comprehending all thofe which appear of one Ample and permanent colour in all lights : fuch are the diamond, carbuncle, ruby, garnet, amethyft, fapphire, beryl, emerald, and the topaz. See Dia¬ mond, Carbuncle, tic. 3 D CHRY- C H R ( 196 ) C II U CHRYSAETUS, in ornithology. See Falco. CHRYSALIS, in natural hiftory, a ftate of reft and , feeming infenfibility which butterflies, moths, and fe- verai other kinds of infedts, muft pafs through before they arrive at their winged or moft perfedt ftate. See Natural History. CHRYSANTHEMOIDES, in botany. See Osteo- spermum. CHRYSANTHEMUM, in botany, a genus of plants belonging to the fyngenefia polygamia fuperflua clafs. The receptacle is naked, it has no pappus ; the calix is hemifpherical and .imbricated ; and the fcales on the margin are membranaceous. There are nineteen fpe- cies, two of which are natives of Britain, viz. the fegetum, or corn mary-gold ; and the leucanthemum, or ox-eye daify, CHRYSOBALANUS, in botany, a genus of the ico- fandria monogynia clafs. The corolla confifts of live petals ; the calix has five teeth ; and the drupa' con¬ tains a nut with five furrows. There is but one fpe- cies, viz. the icaco, a native of America. CHRYSOBERYL, a kind of beryl with a tindlure of yellow. See Beryl. CHRYSOCOLLA, in natural hiftory, afpecies of green ochres. See Qchra. CHRYSOCOMA, in botany, a genus of plants belong¬ ing-to the fyngenefia polygamia aequafis clafs. The receptacle is naked; the pappus is fimpie ; the calix is imbricated and hemifpherical; and the ftylus is hardly longer than the , flofcules. There are nine fpecies, none of which are natives of Britain. CRYSOGONUM, or Moth-mullein, in botany, a genus of plants belonging to the fyngenefia polygamia nece/Taria clafs. The receptacle is paleaceous; the pappus is monophyllous, and three-teethed ; the calix confifts of five leaves; and the feeds are caliculated, and invalved in four leaves.. Thsre is but one fpecies, a native of Virginia. CHRYSOLITE, in natural hiftory, a gem which the ancients knew under the name of the topa?; and the true chryfolite of the ancients, which had its name from its fine gold yellow colour, is now univerlally called topaz by modern jewellers See Topaz. Chrysolite-pctjle, a kind of glafs made in imitation of natural chryfolite, by mixing two ounces of prepa¬ red cryftal, with ten ounces of red-lead, adding twelve grains of crocus martis made with vinegar; and then Raking the whole for twenty-four hours, or longer, in a well luted cucurbit. CHRYTOMELA, in zoology, a genus of infers, be¬ longing to the order of coleoptera. The antennae are ft) aped like bracelets, and thicker on the outfide ; and - neither the breaft not the elytra are marginated There are no lefs than 122 fpecies, principally diftinguifhed, by differences in their colour. CHRYSOPHYTLUM, in botany, a genus of the pen- tandria monogynia clafs. The corolla is bell-fhaped, and divided into ten fegments, which alternately ipread wider ; and the berry contains ten feeds. There are but two fpecies, both natives of America. CHRYSORRASUS, or Chrysoprasius, the tenth of the precious ftones, mentioned in the Revelations, as forming the foundation of the heavenly Jerufalern. The chryfoprafius is a fpecies of prafius, of a pale but pure green colour, with an admixture of yellow. CHRY'SOSPLENIUM, in botany, a genus of the de- candria digynia clafs. The calix is divided into four or five coloured fegments ; it has no corolla; and the capfule has two beaks, and one cell containing many feeds. The fpecies are two, viz. the alternifolium, or alternate leaved golden faxifrage; and the oppofiti- folium, or common golden-faxifrage; both natives of Britain. CHRYSTAL, or Crystal. See Crystal. CHUB, or Chubb, in ichthyology. See Cyprinus. CHURCH, has different fignifications, according to the * different fubjefts to which it is applied, r. It is un- derftood.of the/colledlive body of Chriftians, or ail thole over vhe face of the whole earth who profefs to believe iff Chrift, and acknowledge him to be the Sa¬ viour of mankind. This is what the ancient writers call the catholic .or univerfal church. Sometimes the word church is confidered in a more extenfive fenfe, and divided into feveral branches; as the church mili¬ tant, is the affembly of the faithful on earth; the church triumphant, that of the faithful already in glory ; to which the Papifts add the church patient,, which, according to their dodtrines, is that of the: faithful in purgatory. 2. Church is applied to any particular congrega¬ tion of Chrh'Hans, who affociate together and concur in the participation of all the inftitutions of Jeftis Chrift, with their proper paftors and minifters. Thus we read of the church of Antioch, the church of Alex¬ andria, the church of-Theffalonica-, and the like. 3. Church denotes a- particular fedt of Chriftians diftinguiflted by particular dodlrines and ceremonies. In this fenfe, we fpeak of the Romifh church, the Greek church, the reformed church, the church of England, fee. The Latin or weftern church, comprehends all the churches of Italy, France, Spain, Africa, the north, and all other countries whither the Romans carried their language. G. Britain, part of the Netherlands, of Germany, and of the North, have been feparated frotn hence ever fince the time of Henry VIII. and confti- tute what we call the reformed church, and what the Romanifts call the weftern fchifm. The Greek or eaftern church, comprehends the churches of all the countries anciently fubjedt to the Greek or eaftern empire, and through which their language was carried ; that is, all the fpace extepded from Greece to Mefopotamia and Perfia, and thence into Egypt, This church has been divided from the Roman, ever fince the time of the emperor Phocas. The Gallican eburdh, denotes the church of France, under the government and dir^dlion of their refpedtive bifiiops and paftois. This churcff has always enjoyed -certain franebifes and immunities, not as grants from popes, but as derived to her from her firft original, an‘d which file has taken care never to relifiquifh. Thefe liberties depend upon two maxims ; the firft, that the pope c H U ( 197 ) C H Y pope has no authority or right to commr.nd or order any thing either in general or in particular, in which the temporalities and civil rights of the Jcingdom are concerned; the fecond, that not with ftanding the pope’s fupremacy is owned in cafes purely fpiritual, yet, in France, his power is limited and regulated by the decrees and canons of ancient councils received in that realm. 4. The word church is u/ed to fignify the body of eccl.efiaftics-, or- the clergy, in contradillindlion to the laity. See Clergy. y. Church is ufed for the jtlace where a particular congregration or fociety of Chriftians affemble for the celebration of divine fervice. In this fenfe, churches are varioufly denominated, according to the rank, de¬ gree, difcipline, 6y\ .as metropolitan church, patri¬ archal church, cathedral church, parochial church, collegiate church, drc. See Metropolis, Patri¬ arch, £}c. CnuRCH-ra'in?/, the fame with church wardens. Church-stretto.n, a market-town of Shropfhire, a- bout twelve miles fouth of Shrewfbury : W. long. 20 50', N. lat. $2° 35'. C h u r C n-nuardens, formerly called church-reeves ..are of¬ ficers chofen yearly, in Eafter week, by the mini her 4 and parifhoners of every pari(h, to look after the church, church-yard, church-revenues, 1 ) C I R CINQUEFOIL, quinque/olium, in botany. See Pow TENTILLA. CINQUE PORTS, an appellation given to five port- towns, fituated on the coaft of Kent and Suffex, over- againft France, and famous in Englifh hiftory. The cinque ports are Haftings, Dover, Hithe, Romney, and Sandwich ; which have had large pri¬ vileges granted them, on account of their former great importance, being then not only the keys of the king¬ dom, but confiderable for their maritime ftrength : thus, we are told, that they were obliged to provide eighty fhips at their own charge for forty days, as of¬ ten as the king ftiould have occafion in his wars. Ginque-port is alfo a particular kind of fiftnng-net much ufed in ftanding water, fo called on account of the five entrances into it. CINTRA, a cape and mountain of Portugal, in the pro¬ vince of Eftremadura, ufually called the rock of- Lif- bon, fituated on the north fide of the entrance of the river Tagus : W. long. io° 15', N. lat. 390. CINYRA, or Cinnor, in Jewifh antiquity, generally tranflated cithara, lyra, be. a mufical inftrument ufed before the flood, and invented by Jubah the fon of Lamech. CION, or Cyou, among gardeners, denotes a young fprig, or fprout *f a tree. CIPHER, or Cypher, one of the Arabic charadters, or figures, ufed in computation, formed thus, o. See Arithmetic. Cipher is alfo a kind of enigmatic chara&er, compofed of feveral letters interwoven, which are generally the initial letters of the perfons names for whom the ci¬ phers are intended. Cipher denotes likewife certain fecret charadlers dif- guifed-and varied, ufed in writing letters that contain fpme fecret, not to be underftood but by thofe be¬ tween whom the cipher is agreed on. CIPPUS, in antiquity, a low column, with an inferip- tion, eredted on the high roads, or. other places, to ftiew the way to travellers-,, to ferve as a boundary, to mark the grave of a deceafed perfon, be. CIRG7EA, ovEnc HANTERS NIGHTSHADE, in bota-' ny, a genus of the diandria monogynia clafis. The co¬ rolla confifts of two petals; the corolla has likewife two leaves; and the capfule contains but one feed. The ipecies are three, two of which are natives of Britain, viz% the lutitiana, or enchanters-nightfliade; and the alpina, or mountain enchanters-nightfliade. CIRCASSIA, a country fituated between 40° and yo° E. long, and between 450 and 50° N. lat. It is bounded by Ruflia on the Jnorfh, by Aftracan and the Cafpkin fea on the'eaft, by Georgia and Da- geftan on the fouth, ard by the river Don and the Palus Meotis on the weft. The Circaffian Tartars form a kind of republic, but fometimes put themfelves under the protedlion of Per- fia, and fometimes of Ruflia, or the Turks. They live moftly in tents, removing from place to place for the benefit of paftur,;ge; and are chiefly remarkable, for the beauty of their children, the feragjios of Turky andi C I II ( 2 < •and Perfia being ufually fupplied with boys and young • virgins from this and the neighbouring country of Georgia. CIRCENSIAN games, a general term under which was comprehended all combats exhibited in the Roman circus, in imitation of the Olympic games in Greece. Molt of the feafts of the Romans were accompanied with Circenfian games; and the magiftrates, and other officers of the republic, frequently prefented the people with them, in order to procure their favour. The grand games were held five days, commencing on the i yth of September. There were fix kinds of games exhibited : the firft was wreftling, and fighting with fwords, with ftaves, and with pikes; the fecond was racing; the third, leaping; the fourth, quoits, arrows, and ceftus; all which were on foot; the fifth was horfe-courfing: the fixth courfes of chariots. CIRCIA, in ornithology, a fpecies> of anas, called in engliffi the fummer-teal. and all over of a dulky yel- lowiffi brown, with black feet. CIRCINALIS, in botany, a name ufed by fome for a- diantum, maiden-hair. See Adiantum. CIRCLE, in geometry, a plane figure comprehendred by a fingle curve line, called its circumference, to which right lines drawn from a point in the middle, called the centre, are equal to each other. To find the a- rea of a circle, fee Practical Geometry. Circles of the fphere. See Geography and A- STRONOMY. Circles of latitude. See Geog'raphy. , Circles of longitude. See Geography. Horary Circles, in dialling, are the lines which ffiew the hours on dials, though thefe be not drawn circu¬ lar, but nearly ftreight. See Dialling. Circle, on the globe. See Geography. Po/ar Circle. See Geography. Circle, in logic, or logical Circle, is when the fame terms are proved in orbem by the fame terms; and the parts of the fyllogifm alternately by each other, both diredHy and indirectly. Circles of the empire, fuch provinces and principali¬ ties of the German empire as have a right to be pre- fent at diets. Maximilian I. divided the empire into fix, and fpme years after into ten circles. This laft di- vifion was confirmed by Charles V. The circles, as they Hand in the- Imperial Matricola, are as follows, Auftria, Burgundy,, tht Lower Rhine, Bavaria, Up¬ per Saxony, Franconia, Swabia, Upper Rhine, Weft- phalia, and the Lower Saxony. CIRCOLO MEZZO, in the Italian mufic, denotes a diminution of four quavers or femiquavers, which re- 'prefent a femicircle, proceeding by conjoint degrees. CIRCUIT, in law, fignifies a longer courfe of proceed¬ ings than is needful to recover the thing fued for. Circuit, alfo fignifies the journey, or progrefe, which the judgestake twice every year, through the feveral coun¬ ties of England and Wales, to hold courts and admini- fterjuftice, where recourfe cannot be had to’the king’s courts at Wefiminfler : hence England is divided into •fix circuits, viz. the Home circuit, Norfolk circuit, D2 ) C I R Midland circuit, Oxford circuit, Weftern circuit, and Northern circuit. In Wales there are but two circuits, North and South Wales: two judges are alligned by the king’s commiffion to every circuit. CIRCUIT court, in Scots law, the judges of the fupreme criminal court, or court of judiciary,, are divided into three feparate courts, confiding of two judges each; and the kingdom into as many didxiAs. In certain boroughs of every didridt, each of thefe courts by ro1 tation are obliged to hold two courts in the year, in fpring and autumn ; which are called circuit courts. See Scots Law, Of the fupreme judget and courts of Scotland. CIRCULAR, in a general fenfe, any thing that is de- fcribed or moved in a round, as the circumference of a circle, or furface of a globe. Circular numbers, called alfo fpherical ones, ac¬ cording to fome, are fuch whofe powers terminate in the roots themfelves. Thus, for indance, 5 and 6, all whofe powers do end in 5 and 6, as the fquare of 5 is 25, the fquare of 6 is 36, 'be. CiRduLAR sailing is the method of failing by the arch of a great circle. See Navigation. CIRCULATION, the aft of moying round, or in a circle : thus we fay, the -circulation of the blood, be. Circulation of the blood, the natural motion of the blood in a living animal, whereby that fluid is alter¬ nately carried from the heart into all parts of the bo¬ dy, by the-arteries, from whence it is brought back to the heart again by the'veins. This motipn is chiefly caufed by the the dilatation and contradtion of thE organ, and is the principle on which life depends; for when it ce'afes in any part, it dies; when it is diminilhed, the operations are weak; and, when it ceales totally, life is extinguiffied. All the veins difeharge themfelves into the ventricles of the heart; from hence all the arteries'arife : the blood expelled out of the right ventricle mud be car¬ ried, through the pulmonary artery, into the lungs ; from which it mud be returned, ,by the pulmonary veins, to the left ventricle; from the left ventricle the . blood, thus imported, -is, by the condridlion of that part, again expelled into the aorta, and by it didribu- ted all over the red of the body, and thence is return¬ ed again to the right ventricle by the cava, which com¬ pletes the circulation. This circulation becomes adtually vifible, with the affidance of a microfcope, efperially in fiffi, frogs, be. wherein the inofculation, or union of the extremities of the arteries with thofe of the veins, together with the globules of the blood flowing from the one into the other, may be plainly feen. The auricles of the heart being large hollow muf- cles, furniflied with a double feriesof drong fibres, proceeding with a contrary direction to the oppofite tendons, the one adhering to the right ventricle, the other to the finus venofus ; as alfo with innumerable veins C I R ( 203 ) C I R veins and arteries : by the contraftile force of thefe men ovale, and the trunk of the pulmonary artery, a auricles, the blood wilj^ be vigoroufly exprefled and driven into the right ventricle, which, upon this con- tradtion, is rendered flaccid, empty, and difpofed to admit it. Now, if the right ventricle, thus full of blood, by the contradlion of its fibres, prefs the blood towards the aperture again, the v«nous blood at the fame time pour¬ ing in, will drive it back again into the cavity, and mix it more intimately, till, rifing up againfl: the parietes, it raife the valvulas tricufpides, which are fo connedted to the flelhy columns extended on the oppofite fide, as that, when laid quite down, they cannot clofe the pa¬ rietes of the right ventricle; thefe it thrufts towards the right auricle, till being there joined, they ftop the paffage very clofely, and prevent any return. By the fame means, the fame blood rifes into the three femilunar valves, placed in the extremity of the other mouth, and lying open to the pulmonary artery; thefe it (huts clofe againft the fides- of the artery, and leaves a paffage into the artery alone : the blood car¬ ried by this artery into the lungs, and diilributed by its branches through the whole (ubftance thereof, is firft admitted into the extremities of the pulmonary vein, called aneria venofa ; whence palling into four large vefftls, which unite together, it is brought to the left finus venofus, or trunk of the pulmonary vein, by the force of whofe mufculous ftrudture it is driven into the left ventricle, which, on this occafion, is re¬ laxed, and by that means prepared to receive it. Hence, as before, it is driven into the left ventricle, which is relaxed by the fame means; and by the val- vulat mitrales opening, admit it into the left ventricle, and hinder its flux. into the pulmonary vein : from hence it is forced into the aorta, at whofe orifice there are three femilunar waives, which alfo-prevent a reflux, by clofing the fame. The motion of the blood in living animals is attend¬ ed with the following phenomena: 1. Both the venous finufes are filled, and grow turgid at the fame time. 2. Both auricles grow flaccid at the fame time, and both are filled at the fame time with blood, impelled by the cantraftile force of its correfpondent mufcular venous finus. 3. Each ventricle contrafls and empties itfelf of blood at the fame time; and the two great arte¬ ries are filled and dilated at the fame time. 4. As foon as the blood, by this contraftion, is expelled, both ven¬ tricles being empty, the heart grows larger and broad¬ er. 5. Upon which the mufcular fibres of both' venous finufes contract, and exprefs the blood contained in them into the ventricle of the heart. 6. In the mean time the venous finufes are again filled as be¬ fore, and the auricles, tec. return into their former habitude. 7. This alteration continues till the animal begins to langudh under the approach of death, at which time the auricles and venous finufes make feve- ral palpitations, for one contra&ion of the ventricle. In a foetus, the apparatus for the circulation of the blood is fomewhat-different from that in adults. The feptum, which feparates the two auricles of the heart, 'Is pierced through with an aperture, called the fora- Vol. II. No. 38. 3 little after it has left the heart, fends out a tube into the defcending aorta, called the communicating canal. The foetus being born, the foramen ovale clofes by degrees, and the canal of communication dries up, and becomes a fimple ligament. As to the velocity of the circulating blood, and the time wherein the circulation is completed, feveral com¬ putations have been made. By DrKeil’s account, the blood is driven out of the heart into the aorta with a velo¬ city which would carry it twenty-five feet in a minute: but this velocity is continually abated in the progrefs of the blood, in the numerous fedlions or branches of the arteries, fo that before it arrive at the extremities of the body, its motion is greatly diminifhed. The fpace of time'wherein the whole mafs of blood ordina¬ rily circulates, is varioufly determined. Some ftate it thus : Suppofing the heart to make two thoufand pulfes in an hour, and that at every pulfe there is expelled an ounce of blood ; as the whole mafs of blood is not ordinarily computed to exceed twenty-four pounds, it muff be circulated feven or eight times over in the fpace of an hour. The circulation of the blood was firft difeovered in England, in the year 1728, by Dr Harvey. Circulations/'/^# fap of vegetables. See Vol. I. p. 4J. Circulation, in chemifiry, is an operation whereby the fame vapour, raifed by fire, falls back, to be re¬ turned and diftilled feveral times. Circulation s/'rasw#/. See Commerce, and Mo¬ ney. CIRCULUS, in chemiftry, an iron inftrument in form of a ring, which being" heated red hot, and applied to the necks of retorts and other glafs veffels, till they grow hot, a few drops of cold water thrown upon them, or a cold blalf, will make the necks fly regu¬ larly and evenly off. Another method of doing this, is to tie a thread, firfl: dipt in oil of turpentine, round the place where you would have it break ; and then fetting fire to the thread, and afterwards fprinkling the place with cold water, the glafs will crack exadtly where the thread was tied. CIRCUMAJENTES Muscult, or OsLiqui Mus- culi, in anatomy. See Vol. I. p 290. CIRCUMAMBIENT, an appellation given to a thing that furrounds another on all fides; chiefly ufed in fpeaking of the air. CIRCUMCISION, the ad of cutting off the prepuce ; a ceremony in the Jewifh and Mahommetan religions, wherein they cut off the forelkin of their males, who are to profefs the one or the other law. Among the Jews, the time for performing this rite was the eighth day, that is, fix full days after the child was born : the law of Mofes ordained nothing with refped to the perfon by whom, the inilrument with which, or the manner howj the ceremony was to be performed • the inftrument was generally a knife of (lone* The child is ufually circumcifed at home, where the father, or godfather, holds him in his arms, while the operator 3 F takes C I R ( 204 ) C I R takes hold of the prepuce with one hand, and with the other cuts it off; a third perfon holds a porringer, with fand in it, to c^tch the blood ; then the operator applies his mouth to the part, and having fucked the blood, fpits it into a bowl of wine, and tirrows a ftyp- tic powder upon the wound. This ceremony was ufu- ally accompanied with great rejoicings and feafting, and it was at this time that the child was named in prefence of the company. The Jews invented feveral fuperftitious culloms at this ceremony, fuch as placing three {tools, one for the circumcifdr, the fecond for the perfon who holds the child, and the third for E- iijah, who, the-y fay, affifts invifibly at the ceremony, <&c. The Jews diftinguifhed their profelytes into two forts, according as they became circu'mcifed, or not: thofe who fubmitted to this rite were looked upon as .children of Abraham, and obliged to keep the laws of Mofe's ; the uncircumcifed were only bound to obferve the precepts of Noah, and were called noachidse. This ceremony, however, was not confined to the Jews: Herodotus and Philo Judseus oblerve, that it obtained alfo among the Egyptians and Ethiopians. Herodotus fays, that the cuftom was very ancient a- mong each people, fo that there was no determining which of them borrowed it from the other. The fame hiftorian relates, that the inhabitants of Colchis alfo ufed circumcilion; whence he concludes, that they were originally Egyptians. The Turks never circumcife till the feventh or eighth year, as having no notion of its being necef- fary to falvation. The Perfians circumcife their boys at thirteen, and their girls from nine to fifteen. Thofe of Madagafcar cut the flefli at three feveral times; and the mod zealous of the relations prefent, catches hold of the preputium, and fwallows it. Circumcifion is pradifed on women by cutting off the forelkin of the clitoris, which bears a near refem- blance and analogy to the preputium of the male penis. We are told that the Egyptian captive women were circumcifed; and alfo the fubjeds of Prefter John. Circumcision is alfo the name of a feaft, celebrated on the firft of January, in commemoration of the cir¬ cumcifion of our Saviour. CIRCUMDUCTIONj in Scots law. When parties in a fuit are allowed a proof of addigeamus after the time limited by the judge for taking that proof is elapfed, either party may apply for circumdudion of the time of proving ; the effed of which is, that no proof can afterwards be brought, and the courfe mud be deter¬ mined as it dood when circumdudion was obtained. See Scots Law, title Pobation. CIRCUMFERENCE, in a general fenfe, denotes the line or lines bounding a plane figure. However, it is generally ufed in a more limited fenfe, for the curve line which bounds a circle, and otherwife called a pe¬ riphery; the boundary of a right-lined figure being ex- preffed by the term perimeter. CIRCUMFERENTOR, an indrument ufed by furvey- brs, for taking angles. See Practical Geome¬ try. CIRCUMFLEX, in grammar, one of the accents. See Accent. CIRCUMGYRATION, denotes the whirling motion of any body 'round a center: fuch is that of the planets round the fun. CIRCUMLOCUTION, a paraphradical method of ex- preffing one’s thoughts, or faying that in many words which might have been faid in few. CIRCUMPOLAR Jiars, an appellation given to thofe dars. which by reafon of their vicinity to the pole move round it without fetting. CIRCUMSCRIBED, in geometry, is faid of a figure which is drawn round another figure, fo that all its fides or planes touch the infcribed figure. CIRCUMSCRIPTION, in natural philofophy, the ter¬ mination, bounds, or limits of any natural body. CIRCUMSTANCE, a particularity which, though not effential to any action, yet doth fome way effett it. CIRCUMSTANTIBUS, in law, a term ufed for Apply¬ ing and making up the number of jurors (in cafe any impanelled appear not, or appearing are challenged by any party) by adding to them fo many of the per- fons prefent as will make up the number, in cafe they are properly qualified. CIRCUMVALLATION, o\ line of Circumvalla- tion, in the art of war, is a trench bordered with a parapet, thrown up quite round the befieger’s camp, by way of fecurity againd any army that may attempt to relieve the place, as well as to prevent defertion. CIRCUMVOLUTION, in architeflure, denotes the torus of the fpiral line of the ionic volute. CIRCUS, in antiquity, a great building of a round or oval figure, eredted by the ancients, to exhibit fliews to the people. The Roman circus was a large oblong edifice, arched at one end, encompaffed with porticoes, and furnidied with two rows of feats, placed afcending over each o- ther. In the middle was a kind of foot-bank, or e- minence, with obelilks, datues, and pods at each end. This ferved them for the courfes of their bigse and quadrigse. Thofe that have meafured the circus fay, that it was 2187 feet long, and 960 broad; fo that it was the greated building in Rome: fome fay it would con¬ tain 150,000 people, others 260,000, or 300,000. Circus, in zoology, See Falco. CIRENCESTER, a borough-town of Gloucederfhire, fituated on the river Churn, fifteen miles fouth-ead of Glouceder : W. long. 2°, noth lat. 51° q2/ It fends two members to parliament. CIRLUS, in ornithology. See Emberiza. CIRRI, among botanids, fine drings or thread like filaments, by which fome plants faden themfelves to walls, trees, &c. fuch are thofe of ivy. Cirri, in ichthyology, certain oblong and foft appen¬ dages, not unlike little worms, hanging from the un¬ der jaws or mouths of fome fiflies: thefe cirri, com¬ monly tranflated beards, afford marks to didinguilh the different fpecies of the fifties on which they are found. CIRSIUM, in botany. See Serratula. CIRSOCELE, C I R ( 2< CIR.SOCELE, a fpecies of hernia. See Medicine and Surgery. CISALPINE, any thing on this fide the Alps. Thus the Romans divided Gaul into cifalpine and tranfalpine. CISLEU, in Hebrew chronology, the ninth month of their ecclefiaftical, and the third of the civil year, an- fwering nearly to our November. CISMAR, a town of lower Saxony, in Germany, at a little diftance from the Baltic fea. CISSAMPELOS, in botany, a genus of the dioecia monadelphia clafs. The calix of the male has four leaves; the corolla is wanting; the nedtarium is rota¬ ted ; and. the ftamina are four connefted together. The calix of the female confilts of one ligulated round- ilh-leaf; it has no corolla; the ftyli are three; and the fruit is a berry containing one feed. There are three fpecies, all natives of America CISSOID, in geometry, a curve of the fecond order, firll invented by Diodes, whence it is called the cif- foid of Diodes. See Fluxions. CISSUS, in botany, a genus of the tetrandria monogy- nia clafs. The berry contains but one feed, and is fur- rounded by the corolla and calix, which are both di¬ vided into four fegments. The Ipecies are five, all na7 lives of the Indies. CISTERCIANS, in church-hiftory, a religious order founded in the eleventh century by St Robert, a bene- di&ine. They became fo powerful, that they govern¬ ed almofl; all Europe, both in fpirituals and tempo¬ rals. Cardinal de Vitri defcribing their obfervances, fays, they neither wore fkins nor Hurts; nor ever eat s. flelh, except in fickmfs ; and abftained from filh, eggs, milk, and cheefe: they ky upon ftraw-beds, in their tunics and cowls: they rofe at midnight to prayers : they fpent the day in labour, reading and prayer: and in art their exercifes- obferved a continual filenCe. The habit of the CiHercian monks is a white robe, in the nature of a caffock, with a black fcapulary and hood, and is girt with a wooden girdle. The nuns wear a whi^e tunic, and a black fcapulary and girdle. CISTERN, denotes a fubterraneous refervoir of rain¬ water; or a veffel ferving as a receptacle for rain or other water, for the neceffary ufes of a family. There are likewife lead-cifterns, jar-cilterns, i&ft. See Plumbery and Jar. Authors mention a ciftern of Conftantinople, the vaults of which are fupported by two rows of pillars, 212 in each row, each pillar being two feet in diame¬ ter. They are planted circularly, and in radii tend¬ ing to that of the center. CISTUS, in botany, a genus of the polyandria mono- gynia clafs. The corolla confifts of five petals, and the calix of five leaves, two of ahem being lefs than the other two. The fpecies are 37, and only five of them natives of Britain, viz. the guttulus, or annual ciftus ; the helianthemum, or dwarf ciftus, or fun-flower; the fiirreianus, or narrow-leaved ciftus; the polii-folius, or mountain dwarf ciftus ; and the hir- futus. or hoary dwarf ciftus. CITADEL, a place fortified with four, five, or fix ba- 5 ) CIV ftions, built on a convenient ground near a city, that it may command it in cafe of a rebellion. CITATION, in ecclefiaftical courts, is the fame with fummons in civil courts. See Summons. Citation is alfo a quotation of fome law, authority, or pafiage of a book. CITHARA, in antiquity, a mufical inftrument, the precife ftru&ure of which is not known; fome think it refembled the Greek delta A; and others, the lhape of a half moon. At firft it had only three' firings, but the number was at different times increa- fed to eight, to nine, and laftly to twenty-four. It was ufed in entertainments and private houfes, and played upon with a plectrum or quill, like the lyre.' CITHAREXYLON, in botany, a genus of the didy- namia angiofpermia clafsT The calix is -bell-lhaped, and has five teeth ; the corolla is tunnel ftiaped; and the berry contains two feeds. There are two fpecies, both natives of America. CITHARISTA, or Citharoedus, one who played on the cithara. CITILLE, in zoology, the trivial name of a fpecies of mus. See Mus. CITIZEN, a native or inhabitant of a city, veiled with the freedom and liberties of it. A citizen of Rome was diftinguilhed from a ftranger, becaufe he belonged to no certain commonwealth fub- je<5t to the Romans. A citizen is either by birth or election; and fons may derive the right from their fathers.' To make a good Roman-citizen, it was ne- ceffary to be an inhabitant of Rome, to be inrolled in one of the tribes, and to be capable of dignities. Thofe to whom were granted the rights and privileges of Roman citizens, were only honorary citizens. It was not lawful to fcourge a citizen of Rome. CITRINELLA, in ornithology. See Emberiza. CITRINUS, in natural hiftory, a kind of fprig cryftal, of a fine yellow colour, which being fet in rings is of¬ ten miftaken for a topaz. CITRON-TREE, in botany. See Citrus. CITRULLUS, in botany. See Cucurbita. CITRUS, in botany, a genus of the polyadelphia ico* fandria clafs. The calix is divided-into five fegments ~ the petals are five, and oblong ; and the fruit, is a ber¬ ry, confiding of nine cells. The fperies are three, viz. the medica, or lemon-tree, a native of Alia ; the au- rantiunr, or orange-tree, a native of the Indies ; and} the trifoliata, a native of Japan. CITTADELLA, the capital of the ifland of Minorca, about twenty-three miles weft of Port-mahon : E. long. 30 30/, N. fat. 40°r. CITTADELLAPIEVE, a town of Italy, in the terri¬ tories of the pope, near the lake of Perufa. GIVEN,CHEU, a city of China, the fecond metropolis of the province of Fokien, in 25® N. iat. and 20 9' eaft of Pekin. GIVES, the Englilh name of a fpecies of onion, grow¬ ing in tufts, and feldom exceeding fix inches in height they never produce any bulbs, and are much ufed1 in Tallads in fpring. CIVET, a foft undtucus matter produced in the manner C L A ( 205 ) of mtsfic, in bags growing from the lower part of the belly of a civet-cat. See Castor. Cive r-CAT, the Englifh name of the animal which produces the civet. See Castor. CIVIC Crown, was a crown given by the ancient Ro¬ mans to any foldier who had faved the life of a citizen in any engagement. CIVIDAD de las Palmas, the capital of all the Canary iflands, fituated in the ifland of Canary. Civid ad-real, a city of Spain, in the province of New Calhle : it is the capital of La Mancha, fituated on the river Guadiana, fixty miles fouth of Toledo : W. long. 4q 20N. lat. 390. CIVIL, in a general fenfe, fomething that regards the policy, public good, or peace of the citizens, or fub- je&s of the ftate ; in which fenfe we fay, civil govern¬ ment, civil law, civil right, civil war, eirc. Civil, in a legal fenfe, is alfo applied to the ordinary procedure in an adtion, relating to fome pecuniary -matter or intereft, in which fenfe it is oppofed to cri¬ minal. Civil death, any thing that cuts off a man from civil fociety, as a condemnation to the gallies, perpetual ba- nifhment, condemnation to death", outlawry, and ex¬ communication. Civil law, is properly the peculiar law of each ftate, country, or city: but w'hat we ufually mean by the civil law, is a body of laws compofed out of the beft R.oman and Grecian laws, compiled from the laws.pf nature and nations, and, for the moft part, received and obferved throughout all the Roman dominions for above 1200 years; See Law. Civil war, a war between people of the fame ftate, or the citizens of the fame city. Civil year is the legal year, or annual account of time, which every government appoints to be ufed within its own dominions, and is fo called in contradiftindion to the natural year, which i- meafured exadly by the re¬ volution of the heavenly bodies. CIVILIAN, in general, denotes fomething belonging to the civil law ; but more efpecially the dodors and pro- feftbrs thereof are called civilians. CIV ITA-C ASTELL AN A, a city of Italy, in St Pe¬ ter’s patrimony, fituated near the river Tiber, twenty- five miles north of Rome: E. long. 130, N. lat. 420 ij'. Civita Vecchi,a, a port town and fortrefs of Italy, in St Peter’s patrimony, fituated on a bay of the Me¬ diterranean, thirty miles north-weft of Rome : E. long. 12° 30', N. lat. 420. It is the ftation of the galleys belonging to the pope, who has lately declared it a free port. CLACK, among country-men. To clack wool, is to cut off the ftieep’s mark, which makes the weight lefs, and yields lefs cuftom to the king. •CLACKMANNAN, the capital of Clackmannanfhire,* jn Scotland, fituated on the northern ftiore of the Forth, about twenty five miles north-weft of Edin¬ burgh : W. long. 30 40', N. lat. 56° 15'. The county of Clackmannan is joined with that of C L A Kinrofs, which each in their turn chufe 4 member to reprefent them in parliament. CLAGENFURT, or Clagenfort, the capital of Carinthia, in the circle of Auftria in Germany, 120 miles fouth-weft of Vienna: E. long. 140, N. lat. 47°- CLAIM, in law, a challenge of intereft in any thing that is in poffeflion of another. CLAKIS, in ornithology, a fynonime of the anas ber- nicla. See Anas CLAMP in a /hip, denotes a piece of timber applied to a maft or yard, to prevent the wood from burfting ; and alfo a thick plank lying fore and aft under the beams of the firft orlop, or fecond deck, and is the fame that the rifing timbers are to the deck. Clamp is likewife the term for a pile of unburnt bricks built up for burning. Thefe clamps are built much after the fame manner as arches are built in kilns, viz. with a vacuity betwixt each brick’s breadth for the fire to afcend by; but with this difference, that inftead of arching, they trufs over, or over-fpan; that is, the end of one brick is laid about half way over the end of another, and fo till both fides meet within half a brick’s length, and then a binding brick at the top fi- nilhes the arch Clamp-nails, fuch nails as are ufed to faften on clamps in the building or repairing of fhips. CLAMPING, in joinery, is the fitting a piece of board with the grain, to another piece of board crofs the grain; Thus the ends of tables are commonly clamp¬ ed, to prevent their warping. CLANDESTINA, in botany. See Lathrjea. CLANDESTINE, any thing done without the know¬ ledge of the parties concerned, or without the proper folemnities. Thus a marriage is faid to be clandeftine, when performed without the publication of bans, the confent of parents, 7 ) C L A fignify a defign confifting only of two colours, moft ufually black and white, but fometimes black and yel¬ low ; or it is a defign waflied only with one colour, the fliadows being of a dufky brown colour, and the lights heightened up with white. The word is alfo applied to two prints of two co¬ lours, taken off at twice, whereof there are volumes in the cabinets of the curious in prints. CLARY, in botany. See Salvia. Clary-water, a fpirit drawn from an infufion of the herb clary in fpirit of wine, being a very pleafant and excellent cordial. ‘CLASMIUM, in natural hiftory, conftitutes a diftinift genus of gypfums by itfelf, being more foft, dull, and opake, than other kinds : it neither gives fire with fteel, nor ferments with aqua fortis; but calcines rea¬ dily in the fire, and affords a very valuable plafter. CLASS, an appellation given to the moft general fubdi- vifions of any thing : thus, animal is fubdivided into the clafles quadrupeds, birds, fifties, 6^. which are again fubdivided into feriefes or orders ; and theft laft: into genera. See Natural History, and Bo¬ tany. Class is alfo uftd in fthools, in a fyno^nnous fenfe with•fornr, for a number of boys all learning the fame thing. CLASSIC, or Classical, an epithet chiefly applied to authors read-in the clafles at fchools. This term feems to owe its origin to Tullius Servius, who, in order to make an eftimate of every perfon’s eftate, divided the Roman people into fix bands, which he called claffes. The eftate of the firft clafs was not to be-under 200 1. and theft by way of emi¬ nence were called clajftci, dailies : hence authors of the firft rank came to be called daffies, all the reft be¬ ing faid to be infra claf 'zm : thus Ariftotle is a claf- fic author in philofophy; Aquinus, in fchool-divfi nity, goods and chattels of the debtors : and if they have no good, then he draws them down, to the treafurer’s remembrancer, to write eftreats againft their lands. Clzkk of the pleas, an officer of the exchequer, in whofe office all the officers of the court, having fpe¬ cial privilege, ought to fue, or be fued, in any adion. In this office alfo adions at law may be profecuted by other perfons, but the plaintiff ought to be tenant or debtor to the king, or fome way accountable to him. The under clerks are attorneys in all fuits. Clerks oj'the privy-feal, four officers that attend the lord privy-feal, for writing and making out all things that are fent by warrant from the fignet to the privy- feal, and to be palled the great-feal; and likewife to make out privy-feals, upon fpecial occafions of his majefty’s affairs, as for loan of money, or the like. Clerk of the rolls, an officer of the chancery, whofe bufinefs is to make fearches after, and copies of deeds, officers, dre, Clerk of the fignet, an officer continually attending, upon his majefty’s principal fecretary, who has the: cuftody of the privy-figuet, as well for fealing the: lang’s private letters, as thofe grants .which pafs the king’s hand by bill figned. There are four of thefe officers, who have their diet at the fecretary?s table. Clerk, or Writer, to the fignet, in Scots law. See Scots Law, title 3. Six Clerks, officers in chancery, next in degree be¬ low the twelve matters, whofe bdfinefs is to inrol commiffior.s, pardons, patents, warrants, drc. which pafs the great feal: they were anciently clerici* and forfeited their places if they married. Thefe are-alfo attorneys for parties in fuits depending in the court of chancery. Clerk of the treafury, an officer belonging to the court of common pleas, who has the charge of keeping the re¬ cords of the court, makes out all records of nifi prius, and likewife all exemplifications of records being in the treafury. He has the fees due for all fearches; and has under him an under-keeper, who always keeps one key of the treafury door. Clerk of the warrants, an officer of the common pleas, whofe bufinefs is to enter all warrants of attorney for plaintiffs and defendants in fuit; and to inroll deeds of bargain and fale, that are acknowledged in court, or before a judge. His office is likewife to eftreat into the exchequer all iffues, fines, eftreats, and a- met cements, which grow due to the crown in that court. CLERMONT, a city and biihop’s fee of France, in the territory of Auvergne, and province of. Lyonois, about feventy-five miles weft of Lyons: E. long. 30 20 and N.lat. 450 42'. CLERODENDRUM, in botany, a genus of the di- dynamia-angiofpermia clafs. The calix is bell-fhaped, and divided into five fegments ; the tube of the corolla is filiform; the limbus is divided into five equal parts; the ftatninaare very long; and the berry contains but one feed. The fpecies are two, both natives of the Indies. CLEROMANCY, a fort of divination performed fiy throwing lots, whichVere generally black and white beans, little clods of earth, or pebbles ; alfo dice, or fuch ■ like things, diftinguiflied by certain characters. They caft the lots into a veflel, and having made fupplica- tion to the gods to direA them, drew them out, and, according to the charaAers, conjeAured what fhould happen to them. CLETHRA, in botany, a genus of the decandria mono- gynia clafs. The calix is divided into five fegments ; the petals are five; the ftigma is trifid; and the cap- fule has three cells and three valves. There is but on fpecies, viz. the alnifolia, a native of Carolina. CLEVES, or Clef, the capital of the dutchy of Cleve, in the circle of Weftphalia in Germany, fituated near theweftern fhore of the river Rhine: E. long. 50 36', and N.lat. Ci° 40'. It is fubjeA to the king of Pruffia. CLEVELAND, a dittriA in the north-riding of York (hire, from which the noble fartiily of Fitzroy takes the title of duke. CLIENT, among the Romans, a citizen who put him- felf under the proteAion of fome great man, who, in refpeA of that relation, was called patron. ) C L I This patron aflifted his client with his proteAion, in- •tereft, and goods ; and the client gave his vote for his patron, when he fought any office for himfelf or h;s friends. Clients owed refpeA to their patrons, as thefe owed them their proteAion. The right of patronage was appointed by Romulus, to unite the rich and poor together in fuch a manner, as that one might live without contempt, and the other without envy ; but the condition of a client, in courfe of time, became little elfe but a moderate flavery. Client is now ufed for a party in a lawfuit, who has turned over his caufe into the hands of a counfelloror follicitor. CLIFFORTIA, in botany, a genus of the dioecia poly- andria clafs. The calix of the male confitts of three leaves; it has no corolla; and the ftamina are about thirty. The calix of the female confifts lilkewife of three leaves; and the corolla is wanting; the ftyli are two ; and-the capfule is bilocular, and contains one feed. The fpecies are four, all natives of ^Ethiopia, CLIMACTERIC, among phyficians, a critical year in a perfon’s life, in which he is fuppofed to ftand in great danger, of death. According to fome, every feventh year is a climaAe- ric; but others allow only thofe years produced by multiplying 7 by the odd number 3, 5, 7, and 9, to be climaAerical. Thefe years, they fay, bring with them fome remarkable change with refpeA to health, life, or fortune; the grand climaAeric is the fixty- third year ; but fome, making two, add to this the eighty-firft : the other remarkable climaAerics are the feventb, twenty-firft, thirty-fifth, forty ninth, and fifty fixth. CLIMATE, in geography, a fpace upon the furface of the terreftrial globe, contained between twfc parallels, and fo far diftant from each other, that the longeft day in one differs half an hour from the longeft day in the other parallel. See Geography. CLIMAX, or Gradatton, in rhetoric, a figure where¬ in the word or fexpreflion which ends the firft member of a period begins the fecond, and fo on ; fo that eve¬ ry member will make a diftinA fentence, taking its ■ rife from the next foregoing, till the argument and pe¬ riod be beautifully finifhed; as in the following grada¬ tion of Dr Tillotfon. “ After we have praAifed good aAions a while, they become eafy ; and when they are eafy, we begin to take pleafure in them; and when they pleafe us, we do them frequently ; and by fre¬ quency of aAs, a thing grows into a habit; and con¬ firmed habit is a fecond kind of nature; and fo far as any thing is natural, fo far it is neceflary; and we • can hardly do otherwife ; nay, we do it many times, when we do not think of it.” CLINCH, in the fea-language, that part of a cable which is bended about the ring of the anchor, and then {eized, or made fall. CLINCHING, in the fea-language, a kind of flight caulking ufed at fea, in a profpeA of foul weather, a- bout the polls : it confifts in driving a little oakum in¬ to their feams, to prevent the water’s coming in at them. • CLINIC, C L O ( CLINIC, a term applied by the ancient church-hifto- rians, to thofe who received baptifm on their death¬ bed. Clinic medicine, was particularly ufed for the method of vifiting and treating fick perfons in bed, for the more exadt difcovery of all the fymptoms of their dif- eafe. CLINOIDES, in anatomy. See Vol. I. p. 158. CLINOPODIUM, in botany, a genus of the didynamia gymnofpermia clafs. ' The involucrum is hoary. The fpecies are three, only one of which is a native of Bri¬ tain, viz. the vulgare, or great wild bafil. CLIO, in zoology, a genus of infedts belonging to the order of vermes mollufc^ the body is oblong, and fit¬ ted for fwimming; and it has two membranaceous wings placed oppofite to each other. The fpecies are three, principally diftinguifhed by the (hape of their vagina, and are all natives of the ocean. CLIPEUS, in natural hiftory, a name given to the flat deprefled centroniae, from their refembling a fhield. See Centronia. CLITORIA, in botany, a genus of the diadelphia de- candria clafs. The vexillum is large, open, plaited, and covers the alae. The fpecies are five, all natives of the Indies. CLITORIS, in anatomy. . See Vol. I. p. 276. CLOACA, in Roman antiquity, the common fewer, by which the filth of the city of Rome was carried a- way. CLOCK, a-kind of movement, or machine, ferving to meafure time. The invention of clocks is attributed to Pacificus, archdeacon of Verona, who lived in the time ofLotha rius: others aferibe it to Boetius, about the year y 10 : be that as it will, it is certain, that the art of making clocks, fuch’as are now in ufe, was either firft invent¬ ed, or at leaft retrieved in Germany, about ago years ago; and the invention of pendulum clocks, fo late as the laft age, is difputed between Huygens and Gali¬ leo. For the principles of Clock and IVatcb Work, fee Watch. CLOGHER, a city and bilhop’s fee of Ireland, in the county of Tyrone, and province of Ulfter, fituated twelve miles weft of Armagh : W. long. 70 30', and N. lat. 540 16'. •CLOISTER, an habitation furrounded with walls, and inhabited by religious. In a more general fenfe, it is ufed for a monaftery of religious of either fex. In the firft fenfe, it is the principal part of a regular monaftery, being a fquare furrounded with walls or buildings. It is commonly placed between the church, the chapter-houfe, and re¬ fectory, underneath the dormitory. CLOSE, in heraldry. When any bird is drawn in a coat of arms with its wings clofe down about it, (i, e. not difplayed), and in a Handing pofture, they blazon it by this word clofe ; but if it be flying, they caff it volant. See Volant. CLOT-bird. See Fringilla. CLOTH, in commerce, a manufacture made of wool, wove in the loom. Vol. II. No. 39. Cloths.are-of divers qualities, fine or courfe. The goodnefs of cloth, according to fome, confifts in the following particulars. 1. That the wool be of a good quality, and well drefied. 2. It muft be e- qually fpun, carefully obferving that the thread of the' warp be finer ‘and better twifted than that of the woof. 3. The cloth muft be well wrought, and beaten on the loom, fo as to be every where equally compaCt. 4. The wool muft not be finer at one end of the piece than in the reft. y. The lifts muft be fuflici- ently ftrong, of the fame length with the ftufF, and muft confift of'good wool, hair, or oftrich-feathers; or, what is ftill better, of Daniftt dog’s hair. 6. The cloth muft be free from knots, and pthef imperfections. 7. It muft be well fcoured with fuller’s earth, well fulled with the beft white foap, and afterwards waftt- ed in clear water. 8. The hair or nap muft be well drawn out with the teazel, without being too much opened. 9. It muft be (horn clofe without making it thread-bare. 10. It muft be well dried, n. It muft not be tenter-ftretched, to force it to its juft dimert- fions. 12. It muft be prefled cpld, not hot prefl'ed, the latter being very injurious to woolen cloth. Manufacturing of white cloths which are intended for dying. The beft wool for the manufacturing of cloths are thofe England and Spam, efpecially thofe of Lincoln- . fhire and Segovia. To ufe thofe wools to the beft advan¬ tage, they muft be fcoured, by putting them into a li¬ quor fomewhat more than lukewarifl, compofed of three parts fair water, and one of urine. After the wool has continued long enough in the liquor to foak, and (diflblve the greafe, it is drained and well waflied in running water. When it feels dry, and has no fmell but the natural one of the Iheep, it is faid to be duly fcoured. After this it is hung to dry in the fliade, the heat of the fun making it harfti and inflexible : when dry, it is beat with rods upon hurdles of wood, or on cords, to cleanfe it from dull, and the grofler filth ; the more it is thus beat and cleanfed, the fofter it be¬ comes, and the better for fpinning. After beating, it muft be well picked, to free it from the reft of the filth that had efcaped the rods. It is now in a proper condition to -be oiled, and carded on large iron cards, placed flopewife. Olive oil is efteemed the beft for this purpofe: one fifth of which ftiould be ufed for the wool intended for the woof, and a ninth for that defigned for the warp. After the wool has been well oiled, it is given to the fpinners, who firft card it on the knee with fmall fine cards, and then fpin it on the wheel, obferving to make the thread of the warp fmaller by one third than that of the Woof, and much compaCter twifted. The thread thus fpun, reeled, and made into llceins, that defigned for the woof is wound on little tubes, pieces of paper, or nifties, fo difpofed, as that they may be eafily put in the eye of the fliuttle, That for the warp is wound on a kind of large wooden bobbins, to difpofe it for warping. When warped, it is ftifFen- ed with fize, the beft of which is’ that made of ftireds 3 H of 3 C L O (• 212 of parchment, and when dry, is given to the weavers, who mount it on the loom. The warp thus mounted, the weavers, who are two to each loom, one on each fide, tread alternately on the treddle, firft on the right ftep, and then on the left, which raifes and lowers the threads of the warp equally; between which they throw tranfverfely the {buttle from the one to the other: and every time that the {buttle is thus thrown, and a thread of the woof inferted within the warp, they ftrike it conjunft- ly with the fame frame, wherein is faftened the comb or reed, between whofe teeth the threads of the warp are paffed, repeating the ftroke as often as is ne- ceffary. The weavers having continued their work till the whole warp is filled with the woof, the cloth is fi- niflied; it is then taken off the loom by unrolling it from the beam whereon it had been rolled in propor¬ tion as it was wove; and now given to be cleanfed of the knots, ends of threads, ftraws, and other filth, which is done with iron nippers. In this condition it is carried to the fullery, to be fcoured with urine, or a kind of potter’s clay, well fleeped in water, put along with the cloth in the trough wherein it is fulled. The cloth being again cleared from the earth or urine, is returned to the former hands to. have the leffer filth, fmall draws, taken off as before : then it is returned to the fuller to be beat and fulled with hot water, wherein a fuitable quantity of foap has been diffolved; after fulling, it is taken out to be fmoothed, or pulled by the lids lengthwife, to take out the wrinkles, crevices, eb'c. The fmoothing is repeated every two hours, till the fulling be finifhed, and the cloth brought to its pro¬ per breadth : after which it is wafiied in clear water, to purge it of the foap, and given wet to the carders to raife the hair or nap on the right fide with the thidle or weed. After this preparation the cloth- worker takes the cloth, and gives it its fird cut or {hearing : then the carders refume it, and after wet¬ ting, give it as many more courfes with the teazle, as the quality of the duff requires, always obferving to begin agatnd the grain of the hair, and to end with it ; as alfo to begin with a fmoother thidle, proceed¬ ing dill with one {harper and {harper, as far as the fixth degree. After thefe operations, the cloth being dried, is returned to the cloth-worker, who dicers it a fe- cond time, and returns it to the carders, who re¬ peat their operation as before, till the nap be well ranged on the furface of the cloth, from one end of the piece to the other. The cloth thus wove, fcoured, napped, and {horn, is fent to the dyer; when dyed, it is walhed in fair water, and the worker takes it again wet as it is, lays the nap with a brufh on the table, and hangs it on the tenters, where it is dretched both in length and breadth diffidently to fmooth it, fet it fquare, and bring it to its proper dimenfions, without draining it too much ; obferving to bruffi it afreffi, the way of the nap, while a little moid, on the tenters. ) C L U When quite dry, the cloth is taken off the tenters,, and bruffied again on the table, to finiffi the laying of the nap ; after which it is folded, and laid cold under a prefs, to make it perft&ly fmooth and even, and give it a glofs. Ladly, the cloth being taken out of the prefs, and the papers, r that, nobleman or gentleman. COGS, or Goggles, a kind of flat-bottomed boats u- fed in rivers. COHABITATION, denotes the ftate of a man and a woman who live together like hulband and wife, with¬ out being legally married. By the common law of Scotland, cohabitation for year and day, or a complete twelvemonth, is deemed equivalent to matrimony. CO-HEIR, one who fucceeds to a fhare of an inheri tance, to be divided among feveral. COHESION, in philofophy, that adtion by which the particles of the fame body adhere together, as if they were but one. See Mechanics. * COHORT, in Roman antiquity, the name of part of tfye C O I ( * the'Uoman legion, comprehending about fix hundred men. There were ten cohorts in a legion, thefirftof which exceeded all the reft, both in dignity and num¬ ber of men. When the army was ranged in order of battle, the firft cohort took up the right of the firft line, the reft followed in their natural order, fo that the third was in the centre of the firft line of the legion, and the fifth on the left, the fecond between the firft and third, and the fourth between the third and fifth : the five remaining cohorts formed a fecond line, in their natural order. COIF, the badge of a ferjeant at law* who is called ferjeant of the coif, from the lawn-coif they wear un¬ der their caps when they are created ferjeants. The ufe of the coif was to cover the clerical ton- fure. See Tonsure. COIL. See Quoin. COILON in the ancient Grecian theatres, the fame with the cavea of the Romans. See Cave a. COILOPHYLLUM, in botany. See Sarracena. COIMBRA, a large city of Portugal, in the province of Beira, fituated on the river Mondego, about nine- lix miles north of Lilbon : W. long. 90, and N. lat. 40° 20'. COIN denotes all manner of the feveral ftamps and fpe- cies of money in any .nation. See Money. Coin, in archite&ure, a kind of dye cut diagonal-wife, after the manner of a flight of a ftair cafe, ferving at bottom to fupport columns in a level, and at top to correct the inclination of an entablature fupporting a vault. Coin is alfp ufed for a folid angle compofed of two fur faces inclined towards each other, whether that angle be exterior, as the coin of a wall, a tree, or in¬ terior, as the coin of a chamber or chimney. See Quoin. COINAGE, or Coining, the art of making money, as performed either bs the hammer or mill. Formerly the fabric of coins was different from what it is at prefent. They cut a large plate of me¬ tal into feveral little fquares, the corners of which were cut off with Iheers. After having (haped thefe pieces, fo as to render them perfedlly conformable, in point of weight, to the ftandard piece, they took each piece in hand again, to make it exaftly round, by a gentle hammering. This was called a planchet, and was fit for immediate coining. Then engravers pre pared, as they ftill do, a couple of fteel maffes in form of dyes, cut and terminated by a flat furface, rounded off at the edges. They engraved or ftamped on it the hollow of a head, a crofs, a fcutcheon, or any other figure, according to the cuftom of the times, with a fhort legend. As one of thefe dyes was to remain dor¬ mant, and the other moveable, the former ended in a fquare prifm, that it might be introduced into the fquare hole of the block, which, being fixed very faft, kept the dye as fteady as any vice could have done. The planchet of metal was horizontally laid upon this Inferior mafs, to receive the ftamp of it on one fide, and that of the upper dye, wherewith it was covered, cn the other. This moveable dye, having its round 8 ) * C O I engraved furface refting upon the planchet, had at its oppofite extremity a flat fquare, and larger furface, upon which they gave feveral heavy blows, with a ham¬ mer of an enormous fize, till the double ftamp was fuf- ficiently, in relievo, impreffed on each fide of the plan¬ chet. This being finilhed, was immediately fucceeded by another, and they thus became a ftandard coin, v'hich had the degree of finenefs, the weight and mark, determined by the judgment of the infpeftors, to make it good current money. The ftrong temper¬ ing which was and is ftill given to the two dyes, ren¬ dered them capable of bearing thofe repeated blows. Coining has been confiderably improved and rendered expeditious, by feveral ingenious machines, and by a wile application of the fureft phyfical experiments to the methods of fining, dying, and ftampmg the differ¬ ent metals. The three fineft inftruments the mint-man ufes, are the laminating engine, the machine for making the im« preffions on the edges of coins, and the miH. After they have taken the laminae, or plates of me¬ tal, out of the mould into which they are caft, they do not beat them on the anvil, as was formerly done, but they make them pafs and repafs between the fe¬ veral rollers of the laminating engine, which being gra¬ dually brought clofer and clofer to each other, pre- fently give the lamina its uniform and exadt thicknefs. Ihftead of dividing the lamina into Imall fquares, they at once cut clean out of it as many planchets as it can contain, by means of a lharp fteel trepan, of a round- ifli figure, hollow within, and of a proportionable dia- , meter, to Ihape and cut off the piece at one and the fame time. After thefe planchets have been prepared and weighed with ftandard pieces, filed or fcraped to get off the fuperfluous part of the metal, and then boiled and made clean, they arrive, at laft, at the ma¬ chine, (Plate LXVI. fig. 1.), which marks them upon the edge; and finally, the mill, (fig, 2.) which, fqueezing each of them fingly between the two dyes, brought near each other with one blow, forces the two furfaces or fields of the piece to fill exadfly all the vacancies of the two figures engraved hollow. The engine which ferves to laminate lead, gives a fuf- ficient notion of that which ferves to flaten gold and filver laminae between rollers of a leffer lize. See La¬ minating. The principal pieces of the machine, (fig. 1.), to ftamp coins on the edge, are two fteel laminse, about a line thick. One half of the legend, or of the ring, is engraved on the thicknefs of one of the laminae, and the other half on the thicknefs of the other ; and thefe two laminae are ftraight, although the planchet marked with them be circular. When they ftamp a plamchet, they firft put it be¬ tween the laminse in fuch a manner, as that thefe be¬ ing each of them laid flat upon a copper-plate, which is faftened upon a very thick wooden table, and the planchet being likewife laid flat upon the fame plate, the edge of the planchefc-may touch the two laminae on each fide, and in their thick part. One of thefe laminse is immoveable, and faftened with t'7 Champ okee, V 6 Cke^stetjle r J Cb ossxxets -r~ ( (y^NTJENT CroeEE? » / Civic Tmmplumt Obiidianaii^ 2 ' <3 7 . Oval TNaval Caftcenfis ^Murel cA7> Exn^al ^ TpepcL. Spauilii /urgh. The coinage of each of thefe cities is let out to farm, and makes part of the royal revenue. Perfian Coinage. All the money made in Pcrfia is Aruck with a hammer, as is that of the red of Afia ; and the fame may be underAood of America, and the cpaAs of Africa, and even Mufcovy: the king’s duty, in Perfia, is feven and a half per cent, for all the mo¬ nies coined, which are lately reduced to filver and cop¬ per, theje being no gold coin there, except a kind op medals, at the acceflion of a new fophi. Spanijh Coinage is edeemed one of the lead perfeft in Europe. It is fettled at Seville and Segovia, the only cities where gold and filver are Aruck. COIRE, or Chur, the capita! of the country of the Grifons, in Switzerland, fituated on the river Rhine, fifty-three miles fouth of Condance : E. long. 90 25', N. lat. 46° -40/. COITION. See Generation. COIX, or Job’s tears, in botany, a genus of the monoecia triandria clafs. The calix of the male is a double-flowered glume, without any awn ; the corolla is likewife a glume without an awn : the calix of the female is an open, oval, one-flowered glume ; the Ay- lus is bifid ; and the feed is cartilaginous. There is but one fpecies, viz. the latifoiia, a native of Ja¬ maica. COKENHAUSEN, a fortrefs of Livonia, fituated on the river Dwina, about thirty-two miles ead of Riga : E. long. 250, N. lat. 57°. COLATURE. See Filtration. COLCHESTER, a large.borough-town of Eflex, fitu¬ ated on the river Coin, twenty miles north-ead ,of Chelmsford, on the road to Harwich : E. long. i°, N. lat. 51® 55'. It fends two members to parlia¬ ment. COLCHICUM, or Meadow saffron, in botany, a 3 K genus COL (22 genus of the hexandria trigynia clafs. The corolla is divided into fix fegments, and the tube is radicated ; it has three inflated capfuleS united together. The fpecies are three, only one of which, viz. the au- Lunmale, or meadow-faffron, is a native of Britain. COLD, in general, denotes the privation or abfence of heat; and, confecjuently, thofe \vbo fuppofe heat to confift in a briflc agitation of the component particles of the hot body, define cold to be fuch a faint motion of thefe parts, as is either altogether or nearly imper¬ ceptible to our organs of feeling : in which fenfe, cold is a mere term of relation between the cold body and the organs of fenfation ; and, in faft, the fame body will be. felt either hot or cold, according as the fenfible organ is colder or hotter than it. Cold, in medicine, is found to be produdtive of inflam¬ matory diforders, as coughs, pleurifies, peripneumo- nies, rheumatic pains, confumptions, 6v. See Me- d,i CINE, COLDENIA, in botany, a genus of the tetrandria te- tragynia clafs. The calix has four leaves ; the co¬ rolla is tunnel fhaped ; the fruit confifts of four feeds. There is but one fpecies, a native of India. COLD-FINCH. See Motacilla. COLDSHIRE-IRON, that which is brittle when cold. COLE-FISH. SeeGAous. Cole-mouse, in ornithology. See Parus. COLEOPTERA, the name of Linnaeus’s firfl: order of • infe&s. The infers belonging to this order have four wings ; the upper pair, which ferve as covers to the other two, are cruftaceous, with a ftraight ridge or future in the middle. See Natural History. COLE-SEED, the feed of the napus fativa, or long- rooted, narrow-leaved rapa, called, in Englilh, na- vew, and comprehended by Linnxus among the braf- ficas, or cabbage-kind. See Brassica. This plant is cultivated to great advantage in many parts of England, on account of the' nape-oil expreffed from its feeds. It requires a rich and ftrong foil, e- fpecially in march or fenny lands, thofe newly re¬ covered from the fea, or indeed any other land that is nnk and fat, whether arable or pafiure. The belt feeds are brought from Holland, and fliould be fown about Midfummer, the very day th*t the land is plow¬ ed : a gallon will ferve ah acre. Befides the oil already mentioned, it is likewife cul¬ tivated for winter-food to cattle, and is a very good preparative of land forjoarley or wheat. COLE-WORT. See Brassica. COLIAS, in ichthyology. See Scomber. COLIC, in medicine, afevere pain in the lower venter, ■ fo, called, becaufe the diforder was formerly fuppofed to be feated in the colon. See Medicine. Colic-shell. See Syproea. COLIR, an officer in China, who may properly be cal¬ led an infpeftor, having an eye over what paffes in every court or tribunal of the empire. In order to render him impartial, he is kept inde¬ pendent, by having poll: for life. The power of the colirs is fuch, that they make even the princes of the blood tremble. o ) COL COLISEUM, in ancient architefture, an oval amphi¬ theatre at Rome, built by Vefpafian, wherein were ftatues fet up, reprefenting all the provinces of the empire: in the middle whereof flood that of Rome, holding a golden apple in her hand. This ftru<5hire was fo large, that it would hold near 100,000 fpe£tators. COLITES, in natural hiftory, a name given by fome writers to a kind of pebble, found in the ffiape of the human penis and teftes, and that either fe^arately, or both together. COLLAR, in Roman antiquity, a fort of chain put generally round the neck of Haves that had run away, after they were taken, with an infeription round it, intimating their being deferters, and requiring their being reftored to their proper owners, drc. Collar, in a more modern fenfe, an ornament confift- ing of a chain of gold, enamelled, frequently fet with ■ cyphers or other devices, with the badge of the order hanging at the bottom, wore by the knights of feveral military orders over their (boulders, on the mantle, and its figure drawn round their armories. Thus, the collar of the order of the garter confifls of S S, with roles enamelled red, within a garter en¬ amelled blue, and the George at the bottom'. Lord Mayor's Collar is more ufually called chain. Knights of the Collar, a military order in the republic of Venice, called alfo the order of St Mark, or the medal. It is the doge and the fenate that confer this order; the knights bear no particular habit, only the collar, which the doge puts around their neck, with a medal, wherein is reprefented the winged lion of the republic. Collar of a draught horfe, a part of harnefs made of leather and canvas, and Itufifed with llraw or wool, to be put about the horfe’s neck. COLLARAGE, a tax or fine laid for the collars of wine-drawing horfes. COLLATERAL, any thing, place, country, be. fitu- ated by the fide of another. Collateral, in genealogy, thofe relations which pro¬ ceed from the fame Hock, but not in the fame line of afeendants or defeendants, but being, as it were, afide of each other. Thus, uncles, aunts, nephews, nieces and coufins, are collaterals, or in the fame collateral line: thofe in a higher degree, and nearer the common root, re- prefent a kind of paternity with regard to thofe more remote. COLLATERAL fuccefion, in Scots law: When a de- . fundt, for want of heirs defeended of himfelf, is fuc- ceeded in his eftate by a brother or fifter, or their defeendents, the eftate is faid fo have gone to collate¬ ral heirs. See Scots Law, title, Succejfion in be¬ ret able rights. COLLATION, in the canon law, the giving or beftow- ing of a benefice on a clergyman by a bilhop, who has it in his own gift or patronage. Collation, in common law, the comparifon of pre- fentation of a copy to its original, to fee whether or not it be conformable ; or the report or aft of the of¬ ficer COL (2 ficer who made the comparifon. A collated a