202 ANNUAL KECOKD OF SCIENCE AND INDUSTRY. 



it, is easily soluble in acids and alkalies, does not burn at a 

 red heat even in oxygen. Allowing for impurities, its spe- 

 cific gravity is 1.64. The specific heat was found to be 0.4079. 

 To give a normal atomic heat this value must be multiplied 

 by 13.8, which must be, therefore, its atomic weight. 



Lecoq de Boisbaudran and Jungfleisch have treated 4300 

 kilograms of the zinc-blende of BensberG:, and have obtained 

 from it G2 grams of the new metal gallium, with which they 

 will study its properties. 



Friswell and Greenaway have reinvestigated the com- 

 pound obtained by the former in 1871, and called thallous 

 platinocyanate. It was a colorless body, while the body pre- 

 viously obtained by Carstanjen was blood-red in color. For 

 this purpose platinocyanic acid was produced by the action 

 of sulphuric acid on barium platinocyanate. To one portion 

 an equivalent quantity of thallous carbonate was added, and 

 the solution crystallized ; the result was a colorless salt. To 

 the other portion double this quantity of the carbonate was 

 added ; the result was the dark-red salt referred to, which 

 was a double carbonate and platinocyanate. To confirm this 

 result, barium platinocyanate and thallous sulphate were 

 mixed in solution; the resulting crystals were perfectly col- 

 orless. 



Kern lias described more fully some of the chemical re- 

 actions of his new metal, davyum. The metal itself be- 

 longs to the platinum group, is silver-white in color, hard, 

 malleable at a red heat, and has a density of 9.385 at 25 

 C. It is easily soluble in aqua regia, difficultly so in boil- 

 ing sulphuric acid. Potassium hydrate precipitates its hy- 

 drate yellow, the precipitate being readily soluble in acids, 

 even in acetic. Hydrogen sulphide gives a brown precipi- 

 tate, soluble in alkali sulphides, yielding sulpho-salts. The 

 sulphocyanate is in dark - red crystals, becoming black on 

 heating. The nitrate is a brown mass, and yields a black 

 monoxide on calcination. With potassium cyanide, davyum 

 chloride gives double salts beautifully crystallized. The 

 chloride is soluble in water, in alcohol and ether, and is not 

 deliquescent. It forms double chlorides, that with sodium 

 chloride being almost insoluble in water. Its atomic weight 

 has not been accurately determined, but is believed to be not 

 far from 150. 



