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pitating the antimony by sulphuretted hydrogen, and afterwards the chlorine, by nitrate of silver; the results were

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By passing dry chlorine over heated antimony, combustion of the metal is caused, and a very volatile liquid is formed, being another chloride of antimony; it is white, or of a light yellow colour, and in its external properties resembles Libavius' liquor. It has a strong disagreeable odour, and fumes in the air. Exposed to air, it absorbs water, and becomes a solid crystalline mass; with more water, it heats, and precipitates oxide of antimony. Analyzed in a manner similar to the former compound, it gave40.56 by theory 42.15 59.44

Antimony.
Chlorine

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supposing it to contain 5 proportionals of chlorine to I of metal. When chlorine is passed over the sulphuret of antimony, containing three proportionals of sulphur, the first, or crystalline chloride, is obtained, mixed with chloride of sulphur; upon applying heat, the former dissolves in the latter, and as the solution cools crystallizes again in large crystals.

Sulphurets of Antimony. Having made many experiments on these compounds, M. Rose has found but three; these corresponding with the oxides of the same metal. The compound, with 3 proportionals of sulphur, is the native mineral, and corresponds to the oxide with 3 proportionals of oxygen. It dissolves entirely in muriatic acid, disengaging only sulphuretted hydrogen. It is also formed by passing sulphuretted hydrogen through solution of emetic tartar, or through butter of antimony dissolved in water and tartaric acid. It is, in this case, of an orange colour, but is a true binary sulphuret; as is also kermes mineral; both these being, according to M. Rose, compounds with 3 proportionals of sulphur.

The next compound is obtained by dissolving antimony in nitro-muriatic acid, evaporating to dryness, heating the mass to redness, fusing it with caustic potash, by which it is said to form what is called antimonious acid, and then acting on the fuzed mass with water and muriatic acid until a clear solution is obtained. This solution, precipitated by sulphuretted hydrogen, yields the body in question of an orange colour: by analysis it gave

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The next compound is the golden sulphuret of antimony; the methods of preparing which are well known. It is considered as containing 5 proportionals of sulphur, and by calculation, therefore, is composed of

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The results of experimental analyses differed too little, it is said, from the calculated results, to require that they should be given.

The native compound of sulphuret of antimony, with oxide of antimony, was found to contain

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or, according to M. Rose's views, 1 proportional of oxide of antimony, with 3 proportionals of oxygen, and 2 proportionals of sulphuret, with 3 proportionals each of sulphur.-Ann. de Chim. xxix. 241.

12. On the Detection of Arsenic by Lime Water. The paper from which the following extracts are made is by M. Aug. Ludw. Giseke, and has been published in Schweigger's Journal. We are induced to notice a part of it in consequence of the importance which attaches to any circumstance affecting the indications of arsenical tests. The following process for the detection of arsenic in cases of poisoning, is the joint production of Rose and Berzelius:-" Cut up the coats of the stomach, and place them in the liquid, which is boiled with a few drachms of caustic-potash, in order to dissolve any arsenious acid that might be contained in it. The solution obtained is filtered, heated till it boils, and during the boiling mixed with nitric acid, which is added in small portions as long as any thing separates, and till the liquid has become strongly acid, clear, and of a bright yellow colour; it is filtered while hot; afterwards nearly, not completely, saturated with carbonate of potash, and made to boil, in order to expel the carbonic acid; then it is boiled with clear lime-water as long as any precipitate is formed; the lime-water first saturates the excess of acid, and then precipitates with the arsenious acid as arsenite of lime, and with the phosphoric acid and other animal substances decomposed in the nitric acid. If, instead of saturating the acid with lime-water, you add first caustic alkali till the liquid becomes alkaline and then add lime-water, no precipitate will be formed, because the arsenite of lime is held in solution by the alkali.”

This statement of the solubility of arsenite of time in a solution of alkali, being in contradiction with certain facts, M. Schweigger was induced to examine the circumstances more minutely, and

was ultimately led to the following explanatory experiment:prepare an arsenical liquid, pour it into three glasses, and add to one portion an excess of caustic-potash; to the second, excess of caustic-soda; and to the third, excess of caustic-ammonia. On adding lime-water, a deposit of arsenite of lime will be formed equally in each of the glasses. Now add to each a few drops of acid, (for instance, nitric acid,) yet so that in all the alkali shall predominate; whilst no solution of the precipitate will take place in the glasses that have the potash and soda in them, it will immediately begin in that with the ammonia; and all the arsenite of lime will be finally dissolved, although the ammonia be not saturated by the acid which has been added. Of course, the solution will take place in the three glasses when any acid is in excess; yet, on saturating the acid with alkali, the precipitate will be re-formed immediately in those glasses that contain the potash or soda, but not in that which holds the ammonia, however one may neutralize the liquid.

By putting muriate or nitrate of ammonia into a liquid containing arsenic, and adding lime-water in any quantity, no precipitate will be formed, even though heat be applied. Thus it will be seen, that it is not the ammonia, as caustic alkali, which retains the arsenite of lime in solution, but it is the presence of a soluble salt of ammonia which prevents the formation of the deposit; and if, instead of ammonia, caustic potash or soda be used in the process described by Berzelius, then lime-water will instantly form the precipitate of arsenite of lime.-Phil. Mag. lxvi.

253.

13. Artificial Gold, a new alloy.-Hanover. M. Dittmer has described in the Hanoverian Magazine the following compound of different metals, prepared by the privy-counsellor Dr. Hermstadt, and which may supply the place of gold, not only as to colour, but also for its specific gravity and ductility. The materials consist of 16 parts, by weight, of virgin platina, 7 parts of copper, and 1 part of zinc, equally pure; these metals are to be mixed together in a crucible, covered with powdered charcoal, and perfectly fused so as to form a homogeneous mass.-Rev. Ency. xxvii.

900.

14. Simple mode of obtaining Meconiate of Morphia.-The following process is by Dr. Giuseppe Meneci: reduce good opium to powder, put it into a paper filter, add distilled water to it, and slightly agitate it; in this way wash it till the water passes through colourless; then pass a little diluted alcohol through it; dry the insoluble portion (now diminished to one-half), in a dark place; digest it, when dry, in strong alcohol for a few minutes, applying heat; separate the solution, which, by cooling and after

evaporation, will yield well crystallized meconiate of morphia of a pale straw-colour.-Gior. di Fisica, viii. 218.

15. Rectification of Alcohol at common Temperatures.-M. Paget Descharme proposes to rectify alcohol in the large way by exposing to its vapour deliquescent salts; thus he puts into a vessel with a flat bottom a given quantity of weak alcohol; he then puts a portion of pulverized muriate of lime into a dish, and places it upon feet, or otherwise, over the alcohol in the first; this is closed hermetically, or a cover fastened on by pasted slips of paper, and the whole left for four or five days, in which time the alcohol strengthens, and the muriate deliquesces; the muriate is then removed, and a fresh portion introduced, and this is repeated until the alcohol is sufficiently concentrated. This is an operation common enough in our laboratories: it remains to be seen whether it can be economically adopted in the large way,-Ann. de Chim. xxix. 328.

16. Hygrometric Property of Sulphuric Acid.-The quantity of water that sulphuric acid sp. gr. 1.840 is capable of absorbing from an atmosphere saturated with vapour, has lately been determined, by exposure of 50 grains of acid of the above strength to such an atmosphere. In the course of four months, it gained 423.2 grains of water, considerably more than eight times its original weight, its sp. gr. being diminished to 1.0706.-T. G.

17. Simple method of exhibiting the Deflection of the Magnetic Needle by the Electric Current.-A striking method of exhibiting the deviation of the magnetic needle, whilst under the influence of the voltaic conducting wire, consists in employing one of M. de la Rives' floating spirals, in the centre of which, and parallel with it, is placed a suspended magnetized needle. The moment the plates of an apparatus, so constructed, are dipped into an acid, the needle places itself at right angles to the spiral wire: thus shewing one of the principal facts of electro-magnetism, although upon a small scale, yet in a very decided manner.-T. G.

18. Necessity of Water in the preparation of Lead-plaster.-Attempting to form lead-plaster, the Emplastrum Plumbi of the Pharmacopaice, without the use of water, steam being the source of heat, I was surprised to find after several hours, during which time the litharge and oil had been kept at a temperature of 220°, or thereabout, and constantly stirred, not the slightest appearance of combination; upon the addition of a small quantity of boiling water, the oil and oxide immediately saponified; water appeared, therefore, to be essential to the formation of the plaster. It also appeared probable the oxide might be in the state of hydrate; to

ascertain if such were the case, I precipitated, by potash, the oxide from a quantity of acetate; the precipitate, when washed, was dried by a heat of 220° until it ceased to lose weight: 100 grains, heated to redness in a tube, gave off nearly 8 grains of water, and assumed the orange colour of litharge; the recentlyprecipitated oxide was no doubt, therefore, an hydrate; part of which, with somewhat less than two parts of olive oil, without any addition of water, at a temperature of 212, formed, in half an hour, perfect plaster. Each of these experiments has been repeated with precisely the same results. I am induced to mention this fact, because all pharmaceutical writers limit the action of the water to that of keeping down the temperature.

III. NATURAL HISTORY.

·H. H.

1. On the Insalubrity of the Air of Marshes in communication with the Sea. By M. Gaetano Giorgini.-The observation of M. Giorgini has been drawn to the state of the atmosphere in the neighbourhood of certain marshes on the borders of the Mediterranean; and by reference to historical data, and various documents, he has proved the great importance which attaches to the circumstance of their being, at times, in communication with the sea, so as to have a mixture formed between their waters and that of the sea. Both ancient and modern authors have announced the fatal effects produced in the neighbourhood of marshes by such mixture, and a local belief of the same thing is very common and strong; the opinion has, however, never been supported by any well ascertained and public fact, until the present paper, which contains a case so much in point, and so interesting, as to induce us to insert it at some length.

On the south of the Ligurian Apennines, is a marshy shore, bounded on the west for twelve miles by the Mediterranean, on the south by the River Serchio, and on the north by the River Frigido, a torrent commencing at the foot of the Apennines, in the state of Massa di Carrare, running three or four miles over the land, and then falling into the sea. The plain is from two to four miles wide, and is traversed by a few short torrents ́or streams; among these are the rivers Camajore and Pietra-Santa, which divide the plain into three separate basins.

The rain and spring-waters, which flow into the three basins mentioned, are slowly discharged into the sea by natural or artificial canals, penetrating the sand-bank, which exists on the sea side; these are, first, for the principal basin of the Lake of Massaciuccoli, the ditch of Burlamacca; second, for the smaller Lakes of Torre and Montrone, the ditches of Montrone and Tonfalo;

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