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still is at work. To meet both words signifying "the water of these cases ingenuity has contrived life.” another kind of still, of which we Aqueous, watery. shall hereafter give a representa- AQUILA ALBA, aquila mitigata, tion. The present is an old fa- mercurius dulcis, calomel, mild muriate shioned and common still. a is the of mercury. A combination of mubody, and b the head. The spirit riatic acid and mercury, employed or volatile product, as it rises from as a medicine: the material subjected to heat in a, ARBOR DIANÆ. An amalgamais carried up to b, whence it is tion of mercury and silver, made transmitted into a pipe coiled spi- by mixing a solution of chloride of rally in the tub, d, and called the silver in ammonia with running worm, and terminating and com- mercury. ing out of a hole in d, at c. The . ARCANUM DUPLICATUM, vitriolated tub is filled with cold water, and tartar. A salt very early known, the volatile product in its passage to which a variety of names have through the spiral tube is con- been given; now generally called densed and flows out at c, as a sulphate of potash. fluid, into whatever is placed to ARCANUM TARTARI, secret fiolated receive it. As we intend shortly earth of tartar, essential salt of wine, to enter fully into the principles regenerated tartar, diuretic salt, diand practice of distillation, we shall gestive salt of Silvius; now acetate of now say no more on the subject. potash.

ARCHIL, lichen rocella, archilla, orDICTIONARY OF CHEMISTRY. seille. Properly speaking, archil is APHRITE, earth foam, schaumerde.

the name of a purplish-red dye, A species of carbonate of lime,

prepared by grinding the lichen found in Thuringia and the north

rocella between stones, so as to

bruise but not pound it, and then of Ireland. APLOME. A variety of the gar

moistening it with urine mixed net; a mineral of a deep orange "

with lime. In a few days it be

comes of a purplish-red, and is brown colour. APPARATUS. We only give this then.

vive this then called archil, and at length of as a chemical word, because in

a blue colour, and then it is called some authors the whole of the con

lacmus or litmus. It is a costly dye, tents of a laboratory is described

ed and is seldom used by itself, as it under it.

is very fugitive, except with marAPYROUS, - refractory. Bodies

ble, to which it is said to impart a which resist the action of heat, or

durable and beautiful violet coare unaltered by it, have been

lour. Litmus is employed in checalled Apyrous; but the term re

mistry to make a test paper, and is fractory is at present most gene

then improperly called tincture of rally used,

turnsole. The plant from which AQUA-FORTIS, strong water, nitric

the archil is made is a whitish acid in a weak and impure state.

lichen, and grows at the Canary and It is called single and double, as it

Cape de Verd Islands, and in the is weak or strong, and when much souta of France. concentrated is distinguished by ARDENT SPIRIT, alcohol, spirit of the name-spirit of nitre.

wine. AQUA MARINE, beryl. A precious AREOMETER. An instrument for stone.

measuring the specific gravity of AQUA Regia, or Regis, nitro- fluids. muriatic acid. A mixture of these two acids, formerly so called from 1 ARGAL, argoly bitartrate of potash, its great solving powers.

crude tartar. A substance depoAQUA VITÆ, low wines, ardent sited on the inside of wine casks. spirit of the first distillation. A ge- ARGENTATE OF AMMONIA, fulmineral name for all strong drink, the minating silver..... . :

CHEMISTRY AS A SCIENCE. pit, where it is freed from the scoArt. XVI.

ria which cover it, and is then

taken out with ladles and poured TIN. Copper.

into moulds. It is again exposed · Both these metals are so gene- to a gentle heat, and the purest Tally in use, that their appearance, part which melts first is drawn off, and most of their properties, must , and forms grain tin; the remainder be well known to our readers; we contains a small portion of iron, shall, therefore, only advert to such copper, and arsenic, and is called facts as they are most probably not common tin. What is denomiso well acquainted with. The ores nated stream tin stones in Cornof tin have been found and worked wall, being found in a state of 'chiefly in England, in Germany, powder, is melted in a somewhat and in South America; and they different way. After being washed occur only in that description of it is passed through wire sieves, it mountains which geologists call is then thrown with charcoal into a 1sprimitive, from supposing them to blast furnace, in which it is reduced

be the most ancient parts of the to the metallic state and flows out world. In England, the ores of this below. It is afterwards fused in metal are found chiefly in Corn- an iron pot, and purified by the wall, and from that part of the addition of pieces of charcoal. country our whole supply is obtain- When it appears bright like silver, ed, and some sent abroad. After it is judged to be pure, is drawn off the ore is extracted from the mines, into moulds, and forms good grain it is cleansed by the hand as much tin. In this manner the industry as possible ; it is then reduced to and ingenuity of man extracts from powder in a stamping-mill. This the apparent rubbish which he has

consists of a large cistern, or other brought from the bowels of the ..contrivance, such as large shelves earth this useful metal.

Jaid on a slant, and stampers or The means of procuring tin heavy beams, armed at the ends seems to have been known from with iron, and which are moved the most remote antiquity; for we upwards and downwards by a wa- find both Moses and Homer menter-wheel. A stream of water tion it, and both the coins and the passes through the cistern or over weapons of the ancients were made the shelves; and as the ore is of an alloy of tin and copper. At bruised by the stampers the water present it is not employed for either washes away all the lighter parts, of these purposes. The discoveries and leaves the metallic part of the of art have so improved the manuore free from earthy substances. facture of iron and steel, that weaGreat attention, however, is neces- pons are in Europe now made sary in performing this part of the exclusively from them; and the ., operation, and also in placing the greater durability of gold and silxt, vessels into which the water flows, ver, as well as their greater value,

so that the heaviest substance is which renders a much less quanJeft behind. When the tin ore has tity of them necessary, have enbeen thus pulverized and cleansed, tirely superseded the use of tin as a

it is roasted in a reverberatory fur- coin. In its metallic state at pre"nace to drive off the sulphur, a part sent it is principally employed for

of which, however, is acidified, and covering sheet iron to prevent its rotunites with the copper and the iron rasting; to form plumbers' solder, 10 generally contained in the ore. It speculum pewter, boilers for dyers,

is then again washed, mixed with worms for rectifiers' stills, and one-fifth of its weight of culm, and many other utensils; as also for thrown again into a furnace for coating the inside of copper and about six hours, which reduces the iron vessels, and other similar *oxide of tin, and the metal collects purposes. What is usually called skat the bottom of the furnace. It is tin, however; that substance of afterwards drawn off into a shallow which pots, pans, &c. are made, is,

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in fact, iron coated with tin; and under the name of putty, and is the process by which this is done used for polishing glass; the other is as follows:-The iron is rolled is used in forming the opaque kind into very thin plates, which are of glass called enamel. " Liotong thoroughly cleaned by being rub- Copper, like tin, has been long bed with sand, and by being :im- known, and was even more emmersed for 24 hours in water, ployed than it in the times of the acidulated by muriatic acid. They Greeks, and in still more remote are then heated in an oven to re- antiquity. At present it is chiefly move the scales that may be 'at- procured in Cornwall and in Antached to them, are afterwards glesea in Britain, in Germany, and hammered smooth, and are again in Hungary. The ores from which immersed in an acid solution; they it is obtained are sulphurets, or are then dipped one by one in contain sulphur, and they are thus melted tin, which not only adheres treated:-In Cornwall the o ore, to the surface but penetrates the broken into small pieces, is roasted, metal completely and gives it a being frequently stirred, in a furi white colour. Tin is further em. nace having a long chimney to carry ployed as a material of bell-metal, off the sulphur and arsenic; it is bronze, brass for cannon, and a then put into a small furnace with variety of other well known alloys. a little lime, and fused. Thesim.

Pure metallic tin, of which there purities collect on the surface candy are two kinds, called block tin and aro raked off, from time to time i grain tin, does not, however, differ into oblong moulds; they form hard in colour from the tin which forms masses when cold, and are used as) the covering of the iron sheets. building materials, the copperflows We should probably here remark, out through a hole in the lower as it is common to describe a par- part of the furnace. Fresh quane; ticular kind of sheet tin by the tities of the ore are put in from name of block tin, that we do not time to time, and the process is mean this which consists of iron kept up for a considerable periodib sheets tioned, but the metal as it To free the metal from the arsenic 1 is run into blocks. In this state and sulphur with which it is still tin is chemically described as a mixed, it is beated in a furnace, white metal of great brilliancy, and then suspended in a wella emitting a particular smell when through which a stream of waters rubbed; not very ductile, but very runs. During these processes thet malleable, as it is beat into leaves slag collects on the surface of theq only one-thousandth part of an metal, but as this contains copper, inch thick, and might be made it is again thrown into the furnace thinner if wanted; it is very flexi- with fresh ore. The copper is keptı ble, and produces a remarkable at a low red heat for two days, ands crackling noise; it is harder than is then repeatedly fused and castilead and not so hard as gold; into small moulds. Lastly, itt isb it melts at a temperature of 4420, put with a small quantity of charko but it requires a violent beat to coal into a refining furnace and is cause it to evaporate. It forms again fused, when if it bears thes alloys with most of the metals; and hainıner, it is fit for sale. When what is singalar, when alloyed with the fused copper is run into moulds, lead, the compound is harder and the purest part of it rises to thiet? and possesses more tenacity than top, and may be easily separated tin, the hardest of the two. These from the rest.' In Anglesea i the qualities are greatest when the al. ore, after being, reduced to sfgaģwo Joy is composed of three parts of ments, is put into a kiln, the fluese tin and one of lead.' Like most of of which terminaterina close cham.lt the other metals, tin, combines rea. ber, where the sulphur obtained b dily with oxygen, and forms two from the roasting the onen isteda-v2 oxides, one of which, the yele densed. Here the roasting is keptio low.oxide, is found in commerce up for months together. In Hunot

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gary the process is nearly similar, green colour. Copper melts at a but the copper is fused with about heat nearly the same as is requisite one-twelfth of its weight of lead; to melt gold or silver, and then is and the impurities which it sepa- also of a bluish-green; by a more rates are removed as they form. violent heat it may be made to ed. To ascertain when theimpurities boil and assume the form of vaare all removed, the workman takes pour. If allowed to cool slowly, out a little of the melted metal it crystallizes, or ranges itself in a on the end of a smooth iron rod, determinate manner. It does not and if the metal be pure, it falls off burn till it is exposed to a heat wben the rod is dipped in cold more than sufficient to melt it, but water. When the impurities have in a stream of oxygen gas it burns been removed, the metal is allowed with a blue flame. It does not burn, to cool, and when about to become however, so easily as iron; and is solid, a wet broom is drawn along not liable, like it, to fly off by colliits surface, which converts a thin sion in fragments which catch fire; layer instantly into the solid form. it is, if we may so speak, a much This is as instantly removed and safer metal, and is therefore emplunged into water, which gives it ployed instead of iron to make a fine red colour. The process is hoops for powder barrels, and for repeated till the whole is formed various other purposes, wherever into thin sheets; and these are the powder is manufactured or used. copper sheets used in the arts. The poisonous nature of this metal Copper is also procured from those is well known; and great care waters which contain sulphate of should be taken, wherever copper copper. Pieces of iron are put vessels are used for culinary purinto the water ; they unite with poses, to keep them thoroughly the sulphuric acid, and copper is clean, and never to allow any thing precipitated. When the iron is all to cool in them. Copper rusts, or dissolved, the matter deposited is becomes covered with a green raked out and fused. This pro- crust, by exposure to the air, but cess is said to have been discovered this process goes on slowly, and by a workman accidentally drop the crust, which is very thin, proping a shovel in such waters, wbich, tects the remainder of the metal after laying there some time, was from further corrosion. This crust found covered with copper. Cop- is an oxide of the metal combined per is of a peculiar reddish brown with carbonic acid gas. coloor; it has a styptic and nau The uses of copper are so nuseous taste, and when the hands are merous and familiar, that we shall rubbed over it they acquire a dis not enumerate them. - We have agreeable smell. It is harder than already mentioned several of the silver, and is very malleable, very alloys, such as pinchbeck, bronze, ductile, and possesses great tena and gun metal, of which it forms a city.ll At a degree of heat consider. part, and therefore we only think ably below ignition, the surface of it necessary to add, that gun metal a piece of polished copper is co- is generally formed of about 100 vered with various stripes of the parts of copper and 10 or 12 of tin. prismatic rays, the red of each Its oxides are employed in enamel stripe being nearest the most heat painting, and are manufactured! ed end of the copper.

into several colours. This curious effect is probably owing to the oxidation of the metal, the oxide being thickest where

TO OBTAIN LIQUID SULPHU. ? the heat is greatest. A greater

ROUS ACID. degree of heat oxidates it rapidly, PASS sulphurous acid gas, obso that thin powdery scales form tained by the ordinary methods, on its surface, which may be easily first through a tube filled with rubbed off; at the same time the pieces of chloride of calcium, (muflame becomes of a beautiful bluish siate of lime,) and then into a ma

rass, surrounded by a mixture of in a few minutes the mercury betwo parts of ice and one part sea- comes solid. This is effected more salt. Sulphurous acid is thus lique- rapidly by putting some mercury fied completely under the pressure in a small cup, pouring over it a of the atmosphere, and at a tempe- small quantity of the acid, and rature not lower than 180 to 200 of placing the whole in an air pump, the centigrade thermometer, or from which the air is to be exfrom 0 to 40 of Fabr. It is then bausted. » ini transparent, inodorous, and hea- - SIMPLE MEANS OF LIQUEFYING, vier than water. At 14° Fahr. it boils, but may be preserved liquid ,

* GASES., , .ir for a long time, without having re

It seems to us that the above ex. course to pressure, because the

the periments, which we have transpart which is converted into vapour

lated from a paper by M. Bussy,'in absorbs so much caloric as to pre

the Annales de Chimie et Physique serve the remainder below its boil

for May 1824, are of some imporing temperature. Poured into the

tance. The late experiments of Sir hand, it produces the most intense

Humphrey Davy, on the condenscold, and is completely evaporated.

edation of the gases, give us reason - TO CONVERT WATER INTO ice.

to suppose that it is only necessary Pour some of this sulphurous acid

ascid to discover a cheap and ready into water; one part is converted

ted method of producing that condensinto vapour, another dissolved by ation, to arm the hand of man with the water, but as the water becin's another power as great, if not greatto be saturated, the acid collects er than steam, and attended with in drops at the bottom of the vessel,

essel less danger. M. Bussy has applied like an oil heavier than water. If

if this method of producing a great it'be touched with a tube, or rod, it is degree of cold to liquefy other converted into a vapour, and occa

gases which it is more difficult to sions a species of ebullition: the condense. He begins by drying temperature of the water sinks, and

the gas to be condensed by passing its surface is covered with a coat

it through a tube containing chloof ice; and the whole of the water ride of calcium, to

ř ride of calcium, to which is attachmay be frozen by adding the acid

ed another tube, bent at right anin proper quantity.

gles. The horizontal branch of this TO PRODUCE an excessive DEGREE

latter has a small ball, which he OF COLD.

covers with cotton, and sprinkles Surround the bulb of an air

n air with sulphurous acid; the vertical thermometer with cotton; dip it

branch is plunged into mercury. into sulphurous acid, and then

As the gas passes the ball, it is allow the acid to evaporate spon

condensed into a liquid. By this taneously in the air: By making mcans M. Bussy has liquefied the experiment at the temperature

chlorine, ammonia, and cyanogen; of 100 centigrade (50 of Threat the latter was obtained 'sold and diminution corresponding to -590 crystallized. He proposes to try, of centigrade (or -720 of Fahr..) by the cold produced by evapotakes place; and if the thermome: rating these latter, to liquety those ter is placed in the vacuum of an gases which have hitherto resisted air-pump, the temperature is rea" the art of the chemist, duced to -68° of centigrade, (or stat t sitta -91 Fabr.) It must be observed, 'TO PREPARE FULMINATING however, that only an air thermo

"MERCURY! - rogedo meter can be employed to indicate this low temperature with accu. (In answer to a Correspondent.) racy.

A CORRESPONDENT has partioularly TO FREEZE MERCURY.

requested us to inform him how Cover the bulb of a thermometer this substance is prepared s and as with cotton, pour over it sulphur- he states this knowledge will be of ous acid, and swing it in the air; considerable importance to him,

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