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triumph which promises the most substantial results for this important branch of metallurgical industry. It has been demonstrated that the peculiar properties of steel are not governed absolutely by the presence of a certain percentage of one or two substances, like phosphorus or carbon, but that these properties may be secured and modif{ed at pleasure by judiciously controlling the relative proportions of a number of foreign ingredients introduced into the metal. The progress that has been made in this direction has been intelligently summarized by The Engineering and Mining Journal: “By securing the proper relative proportions of carbon, phosphorus, silicon, and manganese, a steel of great softness and strength can be obtained, while the same percentage of phosphorus in an ordinary steel would have indicated very different properties (which means, in other words, that it would have been quite worthless). There can no longer be much doubt that manganese exerts upon steel a body-giving, toughening influence, as well as a neutralizing effect upon the hardening or cold-shortening due to phosphorus. Though these properties of manganese have been suspected for some time, the mutual dependence, and to a certain extent interchangeability, of carbon and phosphorus were not fully appreciated until M. Tessié du Motay succeeded in producing with ferro-manganese a good steel rail, containing about 0.12 per cent. of carbon, 0.25 of phosphorus, and 0.75 of manganese.” In the light of the recent investigations, therefore, phosphorus is no longer entitled to the evil distinction of being, as a well-known metallurgist has expressed it,“ the very scourge and pestilence of the steel-maker,” and the time is possibly not far away when many rich deposits of ore now esteemed to be worthless will find ready utilization.

GALLIUM. M. Boisbaudran states that in his first discovery of gallium he did not possess more than one hundredth of a milligramme of the metal dissolved in a minute drop of liquid. Lately, with a larger supply of material, he has determined some of its characteristics. The spectrum is exceedingly brilliant, giving with a gas flame the line 417; in a spark spectrum line 403.1 also appears. The metal can be deposited

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electrolytically upon copper, forming a hard layer, difficult to burnish and rather whiter than platinum. It was orig. inally found in a blende from the Pyrenees, but has since been detected in blendes from various other sources, so that the discoverer thinks it may be quite widely diffused. Its most important chemical feature is that it forms apparently a true alum, thus belonging with indium and aluminium in classification. This fact is particularly interesting when considered in connection with a brief article by Mendelejeff. This author some few years ago, in his paper upon the “periodic law,” ventured upon theoretical grounds to predict the existence of several then unknown metals. In all probability gallium is one of these, and will fill a gap which Mendelejeff pointed out in the aluminium group. The verification of such a prophecy might well afford a parallel to the discovery of the planet Neptune.—1 A.

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GALLIUM, M. Boisbaudran has succeeded in isolating about half a gramme of this new metal, and has redetermined some of its leading characteristics. In the fused state it is of a fine silver white color; but in crystallizing it assumes a pronounced bluish tint, and loses considerably in brilliancy. The metal, by cooling from fusion, may be obtained in isolated crystals, which are octahedral. The melting-point, previously put at 29.5° Centigrade, is now, as a mean of six elosely agreeing measurements, fixed at 30,150

Great interest attaches to the specific gravity of gallium. A few months ago it was determined to be 4.7 at 15° Centigrade, the determination being made with a specimen of metal weighing only six centigrammes. But, calculated upon the basis of Mendelejeff's law-the law by which the existence of gallium was predicted the value should have been 5.9. Two new determinations, now published by Boisbaudran, give 5.935 and 5.956. This agreement with theory is very close and very striking.–6 B, LXXXIII., 611, September 18.

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DESILVERIZATION OF ARGENTIFEROUS ZINC. The desilverization process introduced by Parkes in 1850, but subsequently neglected in consequence of the difficulty

of recovering the metallic zinc so as to be re-employed in a continuous process, has been again brought into operation at Tarnowitz, in Silesia. The argentiferous zinc crust is now al. lowed to cool in an iron basin, then placed in the liquating furnace, where, by gentle heating, with full access of air, it is deprived of the greater part of its lead. By this means the zinc is thoroughly oxidized and converted into the so-called zinc dust, which is then distilled between layers of powdered coke, with the production of metallic zinc, free from silver, on the one hand, together with a residue containing the whole of the silver, along with any lead remaining in the zinc dust. -18 A, April 9, 1875, 89.

ON THE FUSIBIL

TY,

TC., OF ALLOYS OF SILVER AND
COPPER.

Mr. Roberts, chemist to the English Mint, has communicated to the Royal Society the result of a detailed elaborate investigation into the liquidation, fusibility, and density of certain alloys of silver and copper. The melting point of the several alloys experimented upon by him varied from 840° Centigrade to 1330° Centigrade, the most fusible alloys being those that contain from sixty to seventy per cent. of silver; and the fusibilities vary very much as to the electric conductivities. The density of pure silver, when fluid, is 9.46; its density when solid is 10.57. This alloy, therefore, on becoming fluid, expands at nearly double the rate that it expands when at ordinary temperatures. Mr. Roberts has also succeeded in obtaining excellent results in the electrodeposition of iron, for which purpose he employs a solution of the double sulphate of iron and magnesia. The iron thus obtained possesses a higher electric conductivity than any commercial iron, and occludes thirteen times its volume of hydrogen. The tube of the metal, which was a vacuum tried at the ordinary temperature, allowed hydrogen to pass through it freely at a dull red heat.

A NEW TEST FOR GOLD.

M. Sergius Kern, of St. Petersburg, in studying the behavior of certain double salts of gold, made the observation that the sulpho-cyanide of potassium was a most sensitive reagent of this metal, which, as experiment proved, would

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indicate the presence of less than the 0.001 of a gramme of gold. He proposes the following procedure: The gold of the sample under analysis is first separated in the usual manner from foreign metals, and next converted by means of sodium chloride into sodio-gold chloride (NaAuCl.); the solution is then concentrated by evaporation. In order to detect the presence of gold, an aqueous solution of potassium sulpho-cyanide (KCyS) is employed, which should contain, for one part of the salt, about fifteen to twenty parts of water. About six grammes of this solution are poured into a test-tube, and some drops of the suspected gold solution, treated in the manner above described, are added. If gold is present, a red-orange turbidity is at once obtained, which soon falls in the form of a precipitate. On gently heating the contents of the test-tube, the precipitate dissolves, and the solution becomes colorless. This reaction is said to be so delicate that one drop of a solution of the sodio-gold chloride (one gramme of the salt in forty grammes of water) affords a decided reaction. The reaction indicates, according to the observer, the formation of a double sulpho-cyanide. -1 A, XXXII., 171.

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PURE PLATINUM AND IRIDIUM. Deville and Debray, obtaining pure platinum and iridium in quantity, have found for these metals rather higher densities than are commonly ascribed to them. The platinum has a specific gravity of 21.5, while that of iridium is 22.421. An alloy containing eighty-five per cent. of platinum to fifteen of iridium, with density 21.618, was found to be very ductile and malleable, and yet quite rigid. Probably it would be useful in the arts. An alloy containing only 66.67 per cent. of platinum, on the other hand, was not malleable.---Supplement to 7 A, December, 1875.

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OSMIUM.

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According to Deville and Debray, osmium is the heaviest substance known, having a specific gravity of 22.477. They have prepared the metal in a crystalline form by passing the vapor of osmic acid over red-hot charcoal. The crystals apparently belong to the first or regular system, and are hard enough to scratch glass. The color is grayish-blue, becom

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ing even violet when the light is reflected several times upon the surface of the metal.--6 B, May 8, 1876.

CONVERSION OF BRUCINE INTO STRYCHNINE. Sonnenschein has shown that brucine may be converted into strychnine by the action of nitric acid, and calls attention to the fact that this discovery may be of practical interest in toxicological investigations, since brucine might be converted into strychnine in course of the examination.35 C, 1875, IV., 212.

OLEANDRINE. It has long been known that oleander leaves contain an active poison, which was first examined by Lukowski in 1861. This body, oleandrine, has lately been reinvestigated by Bettelli, who obtained it in an imperfectly crystalline condition. It is pale yellow, soluble in water, alcohol, ether, chloroform, fusel-oil, and olive-oil. At 56° C. it softens, becomes a greenish liquid at about 70', and at 170° it undergoes partial decomposition. Bettelli also succeeded in forming the chlorhydrate of the alkaloid.—35 C, September 27.

BISULPHIDE OF CARBON AS AN ANTISEPTIC. Hugo Schiff calls attention to the remarkable antiseptic properties of carbon disulphide. A dissected frog, which had served for physiological experiments, was sealed up in a glass vessel, with a few cubic centimeters of the antiseptic, as long ago as 1869; the specimen as yet shows no trace of putrefaction. A similar trial with the entrails of poultry, and another with a small lizard, have resulted likewise. Two hundred grammes of beef, treated with bisulphide, remained for months unaltered ; and then, after cooking, was readily eaten by a dog.–35 C, IX., 828.

MANUFACTURE OF CARBOLIC ACID. The following process for separating carbolic acid from the cresylic and other liquid tar acids was recently patented by Lowe and Gill in England. The partially or wholly bydrated mixtures of tar acids are submitted for a sufficiently prolonged time to a temperature varying between 15° and 56° Fahr. The carbolic acid crystals thus formed are sepa

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