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angle, 166 centimetres long and imported from abroad. We sup. 34 broad; its upper part is, a pose it might be advantageous to square, each side of which mea- import boracic acid from Tuscany, sares 166 centimetres; its per and manufacture, borax in some pendicular height is 170 centi, parts of Great Britain, instead of metres. The whole should be co- continuing to, import the article vered with thick woollen cloth, and from other countries. . placed on some secure foundation, To carry on the operation continu. CHEMISTRY AS A SCIENCE. ally, 18 such vessels are necessary, .
Art. XXI. for it takes 17 or 18 days before
ARSENIC, ANTIMONY. the borax is cooled to the proper We have already bad occasion temperature, viz. tbat of 30° to mention (Chemist, p. 12, No. I.) cent. or 800 Fahr. The place that the substance known in comfor the crystallization should be merce by the name of “ arsenic,” separated from the places where is called arsenious acid, and white the other parts of the operation are oxide of arsenic by chemists. This carried on, in order that it may substance is found native, and is not be disturbed by the vessels re. moreover frequently formed in the ceiving the least shock; and the process of extracting other metals temperature of the room ought as from their ores, and can thus be much as possible to be invariable, abundantly procured without furand about 18° cent, or 65o Fabr.. ther trouble. The basis of this
When the crystallization is com. peculiar substance is a metal, and pleted, which is known by the tem, to this metal the chemists restrict perature arriving at the point men- the name of arsenic. If the white tioned above, the lid is removed by oxide be fused with twice its the aid of a machine, the mother weight of soft soap, and an equal water is drawn off by a syphon, quantity of alkali, and it be poured, and then the lid is again closed and when fused, into a hot iron cone, kept so for six or eight hours, in the metal will be obtained. Or it order that the heat may be slowly may be mixed in a state of powder disengaged, and the crystals may with oil, and exposed in a matrass not crack by a sudden alteration of to the heat of a sand-bath, This temperature. The lid is then again is an offensive process, and can removed, and a workman gets into only be performed where there is the crystallizing vessel, and breaks a brisk current of air to carry off off the crystals, one by one, from the vapours. The decomposed oil the sides. They are afterwards rises first, and the arsenic is after. separated and sorted, and the small wards sublimed in the form of a ones again dissolved. Those which taky metallic substance. The are discoloured by spots of borate metal may also be obtained by of lime or magnesia, are cleaned mixing arsenious acid with half its from these spots by knives and hams weight of blax flux, and putting mers. The borax is then kept in the mixture in a crucible, placing a dry place, in which a fire is lights another over it, inverted, and luted in winter for some days, and is ing both together with clay and afterwards, . when sufficiently dry, sand. Apply a red heat to the agitated in a basket to rub off the lower vessel, when the arsenic will fine angles of the crystals, and be sublimed and deposited on the make it more like the borax which inside of the upper crucible. The is purified in Holland. It is the metal thus obtained has a bluish packed up and sent to market. white colour, somewhat like that This is one example, though a of steel, and it possesses a good comparatively trifling one, of the deal of brilliancy... When heated manner in which chemistry has it emits a strong and very charactaught men how to make those ar teristic odour, resembling the smell tioles for themselves they before of garlic. It is one of the softest merely gathered from nature, or of the metals, and is so britule that it may be reduced to powder in a mineral medicines are all to be mortar. When a strong heat is avoided. We see a considerable : applied it does not melt, but rises number of shops and establishin vapour. Water does not ments in the metropolis, particuaffect it, but when exposed to the larly in the eastern part of it, for air it becomes black, and falls into curing all diseases by means of powder. With one of its oxides herbs. But surely a man may be we have already made our readers as effectually poisoned by hemlock, . acquainted, and of its effects as a or hellebore, or laurel leaves, or poison, under the name of arsenic, opium, or nux vomica, or the juice they have all heard. In all the of the upas tree, as by oxide of vs states with which we are acquaint- antimony,or sulphuric acid. There ed with arsenic, it is a poison, is no ground whatever, therefore, though it is prescribed in agues, for the prejudice, and disease or and with beneficial effects. Real- painful death may ensue from an gar,which is a sulphuret of arsenic, improper use of herbs, which is is formed by the Chinese into cups, seen even in cattle, as well as from and lemon juice which has stood an improper use of minerals. Disin them for a considerable time is cretion, ever-vigilant and watchful used as a tonic. Arsenic unites discretion, guided by knowledge, with other metals, and when cop- is necessary in both cases, and per is alloyed with it, it becomes discarding prejudices, whether of more malleable and flexible, and antiquity or of present imaginings, takes a fine polish. Articles which we ought to rely on it as our surest are to be plated are, on this ac- and best guide. Long experience count, frequently made of this has shown that both mineral and alloy. It forms one of the ingre- vegetable poisons are, in the hands dients also in the specula of reflect- of skilful practitioners, specifics ing telescopes; and mixed with against certain diseases, enabling lead, which it makes more brittle them to mitigate pain and preserve . and more disposed to granulate, it life. What we have to avoid are enters into the composition of shot. those ignorant and pretending Its oxides and sulphurets are em- quacks and empyrics, who address ployed by the dyer, they are useful themselves to our fears and our in purifying flint glass; they form prejudices, incited by no other valuable pigments, and are of ser- motive but to gain their living or a vice in many of the arts. As a fortune, and never care in this metal, arsenic is put separately to pursuit whether or not the health no use, and seems not individually of their patients is wrecked and adapted to any specific purpose, their lives sacrificed. We should
Antimony, the next metal we all take no more medicine than we have to mention, is employed, as can possibly help ; never take any well as arsenic, in medicine, though without its being prescribed for it is not so violent a poison. There us by somebody who understands is reason to believe that an ore of the matter, but certainly we should this metal was known in the time then have no worse opinion of . of the Romans, and was in use as mineral than of vegetable poisons.. an external application for sore Some preparations of antimony eyes. Admitting the very deleteri- have been very long in use as meous nature of some metals, such as dicine, and a few years ago it was arsenic, copper, lead, mercury, &c. the fashionable specific of the day. it is still difficult to conceive what Long after the notion of a univerthere is in them so baneful that it sal medicine was exploded among cannot be equalled by the produc- sensible men, antimony was raised tions of the vegetable kingdom, to that rank by the zeal of its parand what therefore has been the tisans. By others indeed it was as source of that prejudice which loudly decried, and no poison was vaunts the health-giving properties supposed to be so virulent as an of herbs, and teaches men that timony, in all its shapes and forms,
** At present men are more sober Hutchett to make this metal per
concerning both its virtues and fectly brittle. Even the fumes of its deleterious qualities; it is antimony in the neigbbourhood of neither a specific for all diseases, melted gold are sufficient to destroy nor in all cases a deadly poison; it its ductility. Great attention was occupies a more subordinate place formerly paid to this alloy, because in the pharmacopoeia, but still tar- the alchymists thought the quantarised antimony is classed as a tity of gold might be increased by · most valuable medicine. Of the mixing it with antimony. As a virtues of Dr. James's fever pow- metal antimony is put to no seders there seems no doubt, and parate and distinct use;, but it there is as little that the kermes is one of the ingredients of the mineral is a useful medicine, and alloy of which printers' types, and both these also are preparations of also of that alloy of which the antimony.
specula of telescopes, are made. What is called antimony in the Formerly a sulphuret of antimony shops, is a sulphuret of the metal. was used by the ladies to stain Ores of antimony have been found their eye-lashes black; but northern in Sweden, Saxony, Hungary, and beauties, finding that this was not Norway, and in North America. The always an embellishment to their pure sulphuretis separated from the complexions, have either laid aside, earth with which it is contaminated or never adopted this cosmetic, by being exposed to heat in a strong and seem, at present, to content reverberatory furnace, and the men themselves with giving to their tal is afterwards to be obtained by skins the tints of roses, pinks, and fusing the sulphuret with crude lilies. tartar and saltpetre. In this state -it was formerly called regulus of ANALYSIS OF SCIENTIFIC antimony, and now simply anti
JOURNALS. . ·mony. In consequence of the dis- ANNALS OF PHILOSOPHY FOR AUGUST. putes concerning its nature, it has The present Number of the Anbeen very closely and frequently nals is so uninteresting that we are examined. It is of a greyish white almost sorry to waste on it so much colour, and tolerably brilliant. It of our space as is necessary to give has a curious kind of laminated a brief outline of its contents. Mr. · texture, as of thin plates crossing Baden Powell, M.A. F.R.S. con· each other, and sometimes it as- tinues his remarks on Solar Light sumes the form of crystals. It is and Heat, and condescends to in: about as hard as gold, and as brit- form us, which is an opinion not : tte as arsenic. It melts at a de- remarkably new, nor remarkably gree corresponding to 810 of Fahr. well proved, that black bodies are and at a' still higher heat rises in heated more than white ones lry the - vapour. It is not altered either by light they absorb. As to his esti.
air or water, except losing its mate of quantity of light and rium·lustre. But steam, when made to .ber of rays, we have no notion how · pass over red hot'antimony, is de- he measured or numbered what composed very rapidly and with à can neither be grasped or weighed, violent detonation. It unites with and which, though it can be ex' oxygen, and its oxides are used as cluded, is not to be divided. Mr. medicines; it combines also 'with Powell's statements are very logical other metals, forming alloys, some and correct on the supposition that , of which are of considerable usc. the cause of vision is a distinct sub : When combined with iron, it die stance, and that this distinct sabu : minishes its' magnetic power in a stance is reflected in much greater · very remarkable degree. A very quantities by white than by black · small quantity of it also destroys surfaces; but according to the
the ductility of gold: A proporgeneral meaning of terms, the protion of it, not exceeding 1-1920th priety is not evident of applying · part of the gold was found by Mr. the name of substance to the un
050 299 known cause of vision, and which step beyond this fact. That what has for us no other properties what causes vision also causes this ever than the single one of making greater heat in the black than the us see. Light is something in per- white, is by no means proved, fect harmony with the structure We remarked, in speaking of the of our eyes, is adapted to them, former part of Mr. Powell's paper, and, as we know by the blind, that the sun's rise above the hou has no action whatever for us but rizon and the spread of light were through the instrumentality of our coincident, while the heating eforgan of vision. To call it a sub- fect of the sun was not brought stance is only an example of an into action for hours. Even in Mr. eagerness to account for pheno- Powell's experiments, the white mena before they are accurately and black surfaces, the reflection observed. There is, however, no from which caused different de-ih occasion for this, as the wisest of grees of heat, were instantaneously philosophers and most enlightened seen, while the expansion of the observers, they who have pushed mercury in the thermometer, taken their inquiries furthest, and pryed, as the evidence of heat, was not most deeply into the wonders of complete for a minute. We rethe goodly imagery around us all, peat, then, when effects are not agree, that wherever our researches coincident in time, and are so permay stop, the last fact we can fectly distinct as sensations of heat ascertain will be as much replete and sensations of sight, which every with wonder, and as much, or indecd child distinguishes, that it is at infinitely more demand an expla- least a hasty explanation to ascribe nation, than those facts we now them both to the same cause. For endeavour to explain. If this is our parts we are willing to admit necessarily to be the end of our re- that both are caused by the sun; searches, as every man of sense but that there is an intervening knows that it must, why should substance, called light, transmitted we jump to it, by inventing expla- from the sun, possessing we know nations, past all the phenomena not what sort of properties, but which lie between our first concep- producing both sensations of heat tions and this ultimate conclusion and of sight, seems to us one of We wish particularly to caution those useless inventions with which our readers against the very ge- learned men have in all ages en neral mistake of supposing that cumbered the beautiful simplicity, a phenomenon is explained when- and have not explained the phenoever it receives a name. In almost mena of the universe, bu saw every branch of science we find A paper by Sir H. Davy is taken curiosity satisfied, and researches from the Philosophical Transacstopped by the invention of some tions, and its substance has already pretty sounding noun substantive, appeared in some weekly publicaon which the mind reposes as if tions. Then comes an analysis of nothing further were to be learned. the metal of a statue found at Calling light a substance gives un- Lillebonne, which seems published necessary complication to the phe. solely for the purpose of paying a nomena, at the same time that it compliment to Sir Humphrey, by checks research by begetting a contrasting his views with those of notion that the matter is already M. Vauquelin, and showing that explained. Mr. Baden Powell has the oxidation of the metal of this only in this respect adopted the statue was occasioned by its having general opinion, and has advanced been gilded. The gold and the nothing new. It has been stated copper having formed, with the over and over again, that black moisture of the earth, a voltaie cira
surfaces, exposed to the sun, grow cuit, and thus promoted the oxida- hotter than white ones, and we do tion of the copper. This is a connot see that Mr. Powell, in his jecture of M. Labillardiere, and is elaborate paper has gone a single .very ingenious, particularly as cor
roborating and corroborated by in Germany. There is a paper by the late experiments of Sir H. Davy. Dr. Prout, on the acid sometimes In another part of the Annals this found in the stomach, which has subject is again alluded to. We already appeared in the periodipublished in The Chemist, No. V., cals; an account of a rain gauge, a letter, disputing in some mea- an analysis of baryto-calcite, and sure the merit of Sir H. Davy, as an astronomical paper, by Colonel to the discovery of his method of Beaufoy. There is no plate; the preserving copper sheathing; but scientific notices are all old; and we accompanied that letter by the greater part of the articles are some remarks, to show, even if the mere reprints from other works. patentee there mentioned had an- Every paper, however, is the proticipated Sir H. Davy, which we duction of some person who writes did not believe, the value of the a great many letters after his name, application by the latter gentle- and the editors take special care man was not diminished, and the to inform the world that both are principles which led him to it were F.R.S. L. and E. F.L.S., &c., as if certainly not known to the other. they supposed learned titles were Mr. Children, in the present Num- a security against dulness and igber of the Annals, reverts to this norance, and that the world would letter, not, however, as it appeared believe, because a man was adin The Chemist, but in a cotempo- mitted among the oligarchs of rary publication, and hastens, with science, that he was both wise and considerable zeal and warmth, to witty.d uphold the extraordinary merit of the President of the Royal Society, TO PREPARE CITRIC ACID. of which Mr. Children is a member. We have a very high respect
ACIDUM CITRICUM. V tistem for the illustrious President; but To a pint of lemon juice add as among his partisans and followers, much prepared chalk (about an those who belong to his scientific ounce) as will be sufficient to satusect, and look up to him and his rate the juice; mix them, and then Society for approbation and sup- pour off the fluid ; wash the citrate port, there is a narrow and jealous of lime which remains repeatedly apprehension of all other scientific with water; then dry it. After men, Sir H. Davy's merits are so wards pour nine fluid ounces of great, that they can only be exalted diluted sulphuric acid upon the by just comparisons; and it is both dried powder; boil for ten minutes; unwise and harsh in those who are press the liquor strongly through immediately connected with him, a linen cloth, and filter it through to show such a feverish anxiety to paper. Evaporate the clear fluid maintain his superiority. The Pre- with a gentle heat, so that as it sident must at least be considered cools, crystals may form. To renas having been born at a very for- der them pure, dissolve them a tunate period, as it gave him an second and a third time in water: opportunity, which he has well em- filter the solution through paper, ployed, of applying an important and set by to crystallize.-Pharmadiscovery, made by others. The copera.ro
SORBO3 electricity, and the instruments by which he has risen to fame, do not GUM MAKES OIL UNITE bear the name of DAVY, but of
WITH WATER. VOLTA and GALVANI. 302
It is said that dried gum, soaked There are two papers by Mr. in oil, makes the latter unite readily Gray, on the Classification of In- with water. This takes place even sects; two by Berzelius, the Swe- by pouring oil into a mortar, adddish chemist, one on Silica, the ing water; then throwing in gum substance of which has already arabic, in powder, and shaking or appeared in The Chemist; and on stirring the mixture well.-Bulletin the Mineral Waters of Carlsbad, des Sciences Technologiques, 992