INORGANIC CHEMISTRY. 69 Inorganic Chemistry. Alleged Conversion of Phosphorus into Arsenic. By ANASTASIOS K. CHRISTOMANOS (Chem. Zeit., 1900, 24, 943-944).- Arsenic trisulphide, prepared from commercial phosphorus by Fittica's method, was tested for phosphorus and nitrogen, but without success. FRIEDRICH FITTICA replies that it is not surprising that the ordinary methods for the estimation of phosphorus and nitrogen should fail with arsenic, since the methods used for determining nitrogen in inor- ganic amino- or nitro-compounds are known to fail where t h e nitrogen isTmore firmly united, as in the case of many amino- and nitro-organic derivatives. T. H. P. By FRIEDRICH FITTICA (Chem, Zeit., 1900, 24, 991--992).-'l!he exact conditions are given under which, according to the author, phosphorus is oxidised to Conversion of Phosphorus into Antimony.60 ABSTRACTS OF CHEMICAL PAPERS.arsenic and antimony by means of ammonium nitrate and carbonate, and potassium nitrite. The composition PN20 is assigned to arsenic and P2N,0, to antimony. Crystalline Form of Calcium, Barium, and Strontium Sul- phides. By WILHELM MULLER (Cent?. &fin,, 1900, 178-179. Com- pare Abstr., 1898, ii, 376; 1899, ii, 97).-The material examined was prepared by E. Kunheim by heating in an electric furnace the sulphates of the alkaline earths with carbon : carbides are formed to- gether with the sulphides. Cavities are lined with small cubes which are optically isotropic and have a perfect cubic cleavage. Sp. gr. (Kunheim) : calcium sulphide, 2.4-2-5 ; strontium sulphide, 3.336.Mixed crystals of calcium and barium sulphide were also prepared. These sulphides are isomorphous with galena. Cadmium Selenide. By HENRI FONZES-DIACON (Conzpt. rend., 1900, 131, 895-8997).-When cadmium chloride is heated just to its volatilising point in a current of hydrogen selenide, cadmium selenide, Case, is obtained in pale brown, transparent crystals of sp. gr. 5.81 at 15", which, like the zinc selenide obtained under similar conditions (Abstr., 1900, ii, 345), seem to belong to the hexagonal system. A chocolate-brown selenide of the same composition is obtained by the action of hydrogen selenide or alkali selenides on solutions of cadmium salts. The yellow compound obtained by Fabre by the action of sodium selenide on a solution of cadmium iodide, is a double salt of the composition C'd12,3CdSe, which is decomposed by the action of light in the presence of water.The chloride and bromide form similar but less stable compounds. Cadmium selenide, even when crystallised, is easily decomposed by acids, burns readily when heated in oxygen, and is decomposed by chlorine at a moderate temperature, T. H. P. L. J. S. C. H. B. Thallium Chlorobromides. By VICTOR THOMAS (Compt. rend., 1900, 131, 892-8995, Compare Meyer, Abstr., 1900, ii, 655 ; Cush- man, ibid., 725).-Thallium chlorobromide, Tl,C!,Gr,, is obtained by the action of excess of bromine on thallous chloride, and forms small, transparent, sulphur-yellow prisms which seem to be rhombic. They alter somewhat when exposed to air at the ordinary temperature and are decomposed by water, especially on heating.Oxy-acids liberate a large quantity of halogens ; bromine converts the salt into a compound or compounds of the type TI,X,, whilst when heated it yields salts of the type T12X,. The action of varying quantities of bromine on thallous chloride also yields compounds of the types T12X, and T12X6, and these will be described subsequently. C. H . B. Combination of Nitrogen with Metals of the Rare Earth Group. By CAMILLE MATIGNON (Compt. rend., 1900, 131, 837-839. Compare Abstr., 1896, ii, 299; 1900, ii, 726).-Winkler has shown that metallic magnesium liberates the metal from the oxides of thorium, cerium, and lanthanum, and this is now found to be true for the oxides of praseodymium, neodymium and samarium.A mixture of the oxide of the metal and metallic magnesium was strongly heated in anINORGANIC CHEMISTRY. 61 atmosphere of the gas to be investigatedj; it was found that nitrogen, but not argon, is rapidly absorbed by thorium, cerium, lanthanum, praseodymium, neodymium, and samarium. The heat of formation of the oxides of thorium and cerium is greater than that of the oxides of the other metals, the oxide of samarium being the least exothermic. Direct Combination of Hydrogen with the Metals of the Rare Earths. By CAMILLE MATIGNON (Compt. rend., 1900, 131, 891-892). -Neodymium, praseodymium, and samarium combine directly with hydrogen when the metals are liberated in the presence of this gas by the action of magnesium on the corresponding oxides. The hydrides thus formed are dissociated when strongly heated.Samarium Carbide. By HENRI MOISSAN (Compt. rend., 1900,131, 924-926).-Xamarium carbide, SmC,, obtained by heating a compressed mixture of samarium oxide, Sm,O,, with sugar carbon in the electric furnace, has a more metallic appearance than neodymium and praseo- dymium carbides (Abstr , 1900, ii, 726), but small particles are shown by the microscope to consist of transparent, yellow, hexagonal crystals ; it has a sp. gr. 5.86. It is not reduced by hydrogen a t 1000°, but is decomposed by chlorine when gently heated, and by bromine or iodine at a dull red heat. In oxygen a t 400°, the carbide undergoes complete combustion, and it is also attacked by sulphur a t a much higher tem- perature. I n its action on water, samarium carbide resembles yttrium carbide, the gaseous products consisting of acetylene (71 per cent.), olefines (8 per cent.), and hydrogen and paraffins (21 per cent.).The carbide is readily decomposed by acids, and by hydrogen sulphide or By WILLIAM H. EMERSON (Trans. Amer. Inst. Hining Engineers, l900,29,230--248).-Numerous comparative tests were made of the abrasive power of different samples of corundum from Georgia and North Carolina, and partial chemical analyses were made of the same material. There appears to be no close connection between abrasive power and chemical composition. H. R. LE S. C. H. B. hydrogen chloride at a red heat. N. L. Abrasive Efflciency of Corundum. L. J. S. Presence of Ferrous Oxythiocarbonate in the Water of the Rhone. By HENRI CAUSSE (Compt.rend., 1900, 131, 947-949).-At certain periods during the last four years, it has been noticed that the water of the Rhone restores the colour of Schiff’s reagent and exhibits other reactions characteristic of aldehydes. The reactions are first observed in June or July, reach a maximum in September, and disappear later in the year ; they are not given by the water after distillation, or after exposure to air, which causes the formation of an ochreous deposit. Synthetic experiments show that the substance to which the reactions are due is probably ferrous oxythiocarbonate, CO<o>Fe, formed by the combination of carbon dioxide with ferrous sulphide, the latter being the result of the reduction of sulphates by organic matter. S N. L.62 ABSTRACTS OF CHEMICAL PAPERS.Action of Steam and of Mixtures of Steam and Hydrogem on Molybdenum and its Oxides. By MARCEL GUICHARD (Compt. rend., 1900, 131, 998--1001).-The brown molybdenum dioxide, MOO,, resulting from the action of hydrogen on the trioxide a t 470', is com- pletely reduced by a current of the gas a t 600' ; on the other hand, finely divided molybdenum is not oxidised by steam a t temperatures below 700'. From these observations, it follows that the steam produced by the action of hydrogen on the oxides of molybdenum at 600-700° has no tendency to reverse the action, and may be considered as an inert gas; above 700°, however, it is a reagent and the inverse change becomes possible, When molybdenum and its dioxide are heated at these temperatures in a mixture of hydrogen and steam, both reactions, oxidation and reduction, occur simultaneously, and the state of equilibrium finally attained depends on the partial pressures of the constituents of the gaseous mixture.The metal or its dioxide is not affected a t 800' by a current of the gaseous mixture containing its constituents in approximately molecular proportion ; when the pro- portion of steam is larger than this, the metal is almost wholly oxidised to dioxide, whilst excess of hydrogen brings about a complete reduction of the oxide. Bismuth Phosphates. By CLEMENTE MONTEMARTINI and U. EGIDI (Gcczxetta, 1900, 30, ii, 377--381).-The only phosphate obtain- able from bismuth solutions by precipitation and subsequent washing is the ortho-phosphate, BiPO,, which is stable towards water even after boiling for some time, and is almost insoluble in sodium pyro- phosphate solution.T. H. P. General Method of Separating the Metals that accompany Platinum. By EMILIE LEIDIE (Compt. rend., 1900, 131, 888-891). -The residues from the manufacture of platinum and iridium are roasted in the air, heated in hydrogen, washed with dilute hydro- chloric acid, again heated in hydrogen, and then mixed with sodium chloride and heated in chlorine at an incipient red heat. The residue and the volatilised products are treated with water, and the solution allowed to remain until the silver and the greater part of the lead and bismuth have separated as chlorides. The solution is heated at 100" and mixed gradually with excess of sodium nitrite, which precipitates the iron and gold, and afterwards with sodium carbonate, which pre- cipitates lead, copper, bismuth, &c.After boiling for some time, the liquid is filtered, mixed with sodium hydroxide and distilled in a current of chlorine. The osmium and ruthenium are thus volatilised, and can be separated in the ordinary way. The residual liquid is acidified with hydrochloric acid, again mixed with excess of sodium nitrite, and a large quantity of ammonium chloride added, when the iridium and rhodium are precipitated as double ammonium nitrites. The precipitate is dissolved in hot hydrochloric acid, evaporated t o dryness, dissolved in water and mixed with excess of ammonium chloride, which precipitates iridium, but not rhodium. The precipitate is dried and heated a t 450° with its own weight of sodium chloride, which converts the iridium into soluble sodium iridiochloride, and any co-precipitated rhodium into the insoluble anhydrous chloride. G. T. M.MINERALOGICAL CHEMISTRY, 63 The rhodium ammonium chloride is separated by crystallisation, dissolved in water, and converted first into the double sodium nitrite and afterwards into the double ammonium nitrite, which is pre- cipitated, whiJst any traces of iridium that may be present remain in solution. The mother liquor from the iridium and rhodium contains platinum and palladium, and is evaporated t o dryness, heated with concentrated hydrochloric acid to decompose the nitrites, again evaporated to dryness, and strongly heated. The residue is washed with water, dis- solved in aqua regia, evaporated, redissolved and a current of nitric oxide passed into the liquid in order to reduce the palladium and iridium chlorides, after which the liquid is saturated with ammonium chloride to precipitate the platinum. The palladium in the mother liquor is precipitated by adding mercuric cyanide. C. H. B.