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A VOCABULARY

OF

CHYMICAL TERMS,

ACETATES. Salts formed by the acetic acid.

ACIDS mineral, are formed of certain mineral fubftances called acidifiable radicals combined with oxygen.

vegetable, are compofed of carbon, hydrogen, and oxygen, in various proportions.

animal, are composed of the above three fimple substances, in various proportions with the addition of nitrogen.

oxygenated or oxygenized. Acids combined with an additional quantity of oxygen, for particular purposes. The oxygenized muriatic acid ufed in bleaching is an inftance of this fuper-oxygenizement.

hyperoxygenized. Acids which are oxygenized to a maximum.

ACIDULES. A term applied to the natural combination of fome acids with a por tion of potash. The oxalic acid and the tartaric are the only acids that have hitherto been found in this state of semi-faturation.

AERIFORM fluids. Fluid fubftances combined with an additional portion of caloric fufficient to give them the gaseous form.

AFFINITY. A term used to exprefs that peculiar propenfity which different species of matter have to unite with each other, or with portions of matter of their own fpecies. of aggregation. A force by which two bodies of the fame kind tend to unite, and by which an aggregate is formed without the chymical properties of the fubftances being at all changed.

of compofition. A force by which fubftances of different kinds unite, and by which matter is formed whofe properties are different from thofe of the bodies before their combination. This attraction is stronger in proportion as the nature of the bodies is different, between which it is exerted.

AGGREGATES. Subftances whofe parts are united by cohesive, and not by chymical attraction. See Affinity of aggregation.

ALBUMEN. The modern name for coagulable lymph. It is that peculiar animal fubftance which forms the ferum of the blood, the white of eggs, and other compounds.

ALCOHOL. Rectified spirit of wine. When good, its fpecific gravity is only 0.836. ALEMBIC. The term formerly given to the ftill ufed by chymifts for their diftilla. tions.

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ALKALIES. Peculiar fubftances which have an urinous, burning, and cauftic taste, and a ftron tendency to combination. When united with acids they form mild alkaline falts. See page 108.

ALLOYS.

A combination of any two metals, except mercury, is called an alloy. Thus old is alloyed either with filver or copper, for the purposes of coinage. ALLUVIAL. By alluvial depofitions is meant the foil which has been formed by the deftruction of the mountains, and the washing down of their particles by torrents of water.

AMALGAM. A combination or mixture of

mercury with

any other metal, is called

an amalgam. AMMONIACAL falts. Salts formed with ammonia, or volatile alkali. AMYLACEOUS. A term applied to thofe vegetable fubftances which contain

ftarch.

ANALYSIS. The refolution of a fubftance into its conftituent parts, for the purpofe of examination.

ANNEALING. The art of rendering fubftances tough which are naturally hard and brittle. Glafs and iron are annealed by gradual cooling; brafs and copper by heating, and then fuddenly plunging them in cold water,

APPARATUS chymical. This term is defcriptive of all the utenfils made ufe of in

a chymical laboratory. The principal are ftills, furnaces, crucibles, retorts, receivers, matraffes, worm tubs, pneumatic troughs, thermometers, &c.

AREOMETER. A graduated glafs inftrument with a bulb, by which the specific gravity of liquids is afcertained. Baumé's areometer is that which is chiefly referred to when the French writers fpeak of this inftrument.

ARGILLACEOUS. A term defcriptive of thofe earths which contain alumine or clay.

AROMA. A term ufed for the odour which arifes from certain vegetables, or their infufions.

ARSENIATES. Salts formed by the acid of arfenic.
ATMOSPHERES. We use this term to exprefs the degree of additional preffure

given to fluids. Thus, if in order to impregnate water with any of the gafes, I
give it a preffure of 15lbs. upon every fquare inch of furface, I am said to give it
one atmosphere; if 30lbs. two atmospheres, &c. &c.

ATTRACTION, Chymical attraction is a term fynonymous with affinity; which

fee.

AURUM-MUSIVUM. A combination of tin and fulphur. It is also called mufive gold, and mofaic gold.

AZOTE. A peculiar fimple fubftance, fynonymous with nitrogen. It enters into a variety of compounds, and forms more than three parts in four of atmospheric air. See page 55.

AZOTIC gas, Azote or nitrogen rendered gafeous by caloric,

B.

BALLOON. A term given by the French to their fpherical chymical receivers. BALSAMS. Certain aromatic refinous fubftances, which are obtained from fome trees by incifions. Of this kind are the Canada balfam, the balfam of Copaiva, the balfam of Tolu, &c. BAROMETER. An inftrument which shows the variation of the preffure of the atmosphere, by the rife or fall of a column of mercury in a graduated glass tube. BASE. A chymical term, ufually applied to denote the earth, the alkali, or the metal which is combined with an acid to form a falt.

BATHS. Veffels for diftillation or digestion, contrived to tranfmit heat gradually and regularly.

Jand, Veffels filled in part with dry fand, in which those retorts are placed which require a greater heat than can be given by boiling water. In large works iron plates are used instead of veffels of capacity. They are often called Land beats.

water. Veffels of boiling water, in which other veffels containing the mate ters to be distilled or digefted are placed, in order that the fame heat may be kept up throughout the whole of any particular procefs,

BENZOATES. Salts formed by the benzoic acid,

BITTERN. The mother-liquor which remains after the cryftallization of muriate of foda (fea falt). It generally contains fulphate of magnesia, and a small portion of fulphate of foda.

BITUMEN. A generic term, applied to a variety of foffil inflammable fubftances. BLOW-PIPE. An inftrument to increase and direct the flame of a lamp for the analysis of minerals, and for other chymical purposes.

BOLT-HEAD. A round chymical veffel with a long neck, ufually employed for digeftions. It is alfo called a matrafs.

BOMBATES. Salts formed by the bombic acid.

BORATES. Salts formed with the acid of borax.

BUTTON. A name given to the fmall round piece of metal which is found at the bottom of a crucible after a metallic ore or an oxide of nietal has been reduced for experiment.

C.

CALCAREOUS. A chymical term formerly applied to defcribe chalk, marble, and all other combinations of lime with carbonic acid.

CALCINATION. The application of heat to faline, metallic, or other substances; fo regulated as to deprive them of moisture, &c. and yet preserve them in a pulverulent form.

CALORIC. The chymical term for the matter of heat.

free. Is caloric in a feparate ftate, or, if attached to other fubftances, not chymically united with them.

latent. Is the term made ufe of to express that portion of caloric which, is chymically united to any fubftance, fo as to become a part of the faid fubftance.

CALORIMETER.

An inftrument for ascertaining the quantity of caloric difengaged from any substance that may be the object of experiment. CALX. An old term made ufe of to defçribe a metallic oxide,

CAMPHORATES. Salts formed by the camphoric acid.

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CAPILLARY. A term ufually applied to the rife of the fap in vegetables, or the rife of any fluid in very fmall tubes; owing to a peculiar kind of attraction, called capillary attraction.

CAPSULES. Are fmall faucers of clay for roafting famples of ores, and for smelting them to afcertain their value.

CAPUT-MORTUUM. A term fignifiying dead-bead, being that which remains in a retort after diftillation' to dryness.

CARBON. The bafis of charcoal. See page 178.

CARBONATES. Salts formed by the carbonic acid.

CARBURETS. Compound fubftances, of which carbon forms one of the conftituent parts. Thus plumbago, which is compofed of carbon and iron, is called carburet of iron.

CAUSTIC common. Soda or potash deprived of its carbonic acid, and fufed, fometimes with the addition of lime, into a folid fubftance.

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lunar. Nitrate of filver evaporated to drynefs, and fufed in a crucible. A folution of this falt is ufed by chymists as a teft for muriatic acid. CAUSTICITY. That quality in certain fubftances by which they burn or corrode animal bodies to which they are applied. It is beft explained by the doctrine of chymical affinity. See page 109.

CEMENTATION.

A procefs by which metals are purified or changed in their qualities by heat, without fufion, by means of a compofition, called a cement, with which they are covered. Thus iron, by being kept a long time in a certain degree of heat, furrounded by charcoal powder, is converted into steel. CHALYBEATE. A term descriptive of those mineral waters which are impregnated with iron. See Martial.

CHARCOAL. Wood burnt in clofe veffels: it is an oxide of carbon, and generally contains a small portion of falts and earth. Its carbonaceous matter may be converted by combuftion into carbonic acid gas.

CHATOYANT. A term much ufed lately by the French chymifts to defcribe property in fome metallic and other fubftances, of varying their colours according

to the way in which they are held; as is the cafe with the feathers of some birds, which appear very different when feen in different pofitions.

CHERT. A term made ufe of in defcribing a species of filiceous ftones, which are coarfer and fofter than the common filex. It is often found in large masses in quarries of limestone.

CHROMATES. Salts formed by the chromic acid.

CITRATES. Salts formed by the citric acid.

COAL. A term applied to the refiduum of any dry distillation of animal or vege,

table matters.

COHESION. A force inherent in all the particles of all fubftances, excepting light and caloric, which prevents bodies from falling in pieces. See Affinity. COHOBATION. When a diftilled fluid is poured again upon the matter from which it was diftilled, in order to make it stronger, it is called cohobation. It is not much practifed by modern chymifts.

COLUMBATES. Salts formed with the columbic acid.

COMBINATION. A term expreffive of a true chymical union of two or more fubftances; in oppofition to mere mechanical mixture.

COMBUSTIBLES, Certain fubftances which are capable of combining more or lefs rapidly with oxygen. They are divided by chymifts into fimple and compound

combustibles.

COMBUSTION. The act of absorption of oxygen by combuftible bodies from atmofpheric or vital air. The word decombustion is fometimes used by the French writers to fignify the oppofite operation.

COMMINUTION. The reduction of hard bodies into fmall particles. By thi procefs the heavieft fubftances may be made to float in the lightest fluids. CONCENTRATION. The act of increasing the specific gravity of bodies. The

term is ufually applied to fluids which are rendered stronger by evaporating a portion of the water which they contain.

CONDENSATION. The act of bringing the component parts of vapour, or gas, nearer together by preffure, or by cold. Thus atmospheric air may be condenfed by preffure, and aqueous vapour by the fubtraction of caloric, till it is converted into water.

CRUCIBLES. Veffels of indifpenfable use in chemistry in the various operations of fufion by heat. They are made of baked earth, or metal, in the form of an inverted cone.

CRYSTALLIZATION. An operation of nature, in which various earths, falts, and metallic fubftances, pafs from a fluid to a folid state, affuming certain determinate geometrical figures.

water of. That portion which is combined with falts in the act of crystallizing, and becomes a component part of the faid faline fubftances. CUPEL. A veffel made of calcined bones, mixed with a small proportion of clay and water. It is ufed whenever gold and filver are refined by melting them with lead. The process is called cupellation.

D.

DECOMBUSTION. Synonymous with deoxidation; which fee.

DECOMPOSITION. The feparation of the conftituent principles of compound bodies by chymical means.

DECREPITATION. The fudden decompofition of falts, attended with a crackling noife when thrown into a red-hot crucible, or on an open fire.

DEFLAGRATION. The act of burning two or more fubftances together, as charcoal and nitre, or nitre and fulphur.

DELITE. A term used by some of the French writers, fignifying to break, by the action of the air, like a foft ftone into layers. See Annales de Chimie, tom. xix. 79.

DELIQUESCENCE of folid faline bodies, fignifies their becoming moift, or liquid, by means of water which they abforb from the atmosphere in confequence of their great attraction for that fluid.

DELIQUIUM. Is the ftate of potash, or any deliquefcent falt, when it has fo far deliquefced by expofure to the air as to have become a liquid.

DEOXIDATE, or DEOXIDIZE. To deprive a body of oxygen.

DE-OXIDATION, or DIS-OXIDATION. A term made ufe of by fome writers to exprefs that operation by which one fubftance deprives another fubftance of its oxygen. It is called unburning a body by the French chymifts. De-oxidizement is a better term. DEPHLEGMATION. Is the act of feparating the water from chymical liquors. DEPHLOGISTICATED. A term which was given by Dr. Priestley to oxygen gas. When he first discovered this gas, he called it dephlogisticated air.

DEPURATION. The purging or feparating any liquid in a ftate of purity from its fæces or lees.

DETONATION. An explosion with noife.

It is most commonly applied to the

explosion of nitre when thrown upon heated charcoal.

DIGESTION. The effect produced by the continued soaking of a solid substance in a liquid, with the application of heat.

DIGESTOR Papin's. An apparatus for reducing animal or vegetable substances to a pulp or gelly expeditiously.

DISTILLATION.

A procefs for feparating the volatile parts of a substance from the more fixed, and preferving them both in a state of separation. DOCIMASTIC ART. The art of affaying metals.

DUCTILITY. A quality of certain bodies, in confequence of which they may be. drawn out to a certain length without fracture.

DULCIFICATION. The combination of mineral acids with alcohol. Thus we have dulcified spirit of nitre, dulcified fpirit of vitriol, &c.

E.

EDULCORATION. Expreffive of the purification of a fubftance by washing with

water.

EFFERVESCENCE. An inteftine motion which takes place in certain bodies, oc cafioned by the fudden efcape of a gafeous fubstance.

EFFLORESCENCE. A term commonly applied to thofe faline cryftals which become pulverulent on expofure to the air, in confequence of the lofs of a part of the water of cryftallization.

ELASTICITY.. A force in bodies, by which they endeavour to restore themselves to the pofture from whence they were difplaced by any external force. page 43.

See

ELASTIC FLUIDS. A name fometimes given to vapours and gafes. Vapour is called an elastic fluid; gas, a permanently elastic fluid. ELECTIVE ATTRACTIONS. A term ufed by Bergman and others to defignate what we now exprefs by the words chymical affinity; which fee. When chymists

first obferved the power which one compound fubftance has to decompofe another, it was imagined that the minute particles of fome bodies had a preference for fome other particular bodies; hence this property of matter acquired the term elective attraction.

ELEMENTS. The fimple, conftituent parts of bodies, which are incapable of decompofition; they are frequently called principles.

ELIQUATION. An operation whereby one fubitance is feparated from another by fufion. It confifts in giving the mafs a degree of heat that will make the more fufible matter flow, and not the other.

ELUTRIATION. The operation of pulverizing metallic ores or other fubftances, and then mixing them with water, fo that the lighter parts which are capable of fufpenfion may be poured off, and thus feparated from the groffer particles. The metallic fubftances which are reduced to an impalpable powder are prepared by this procefs.

EMPYREUMA.

A peculiar and indefcribably disagreeable fmell, arifing from the burning of animal and vegetable matter in cofe veffels.

EOLIPILE. A copper veffel with a fmall orifice, and partly filled with water. It is made hot, in order that the vapour of the water may rush out with violence, and carry a ftream of air with it to increase the intenfity of fires. It is an inftrument of great antiquity.

ESSENCES. What are called effences in chymistry and pharmacy are the e oils obtained by diftillation from odoriferous vegetable substances. ESSENTIAL SALTS. The faline fubftances found in plants, and v

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