CHEMISTRY. 443 



tallizes out. For tlie now acid the nainc (lisulplioix'isulplimic is jno- 

 postd. (Compt. KiMul., cvi,8o] aud 1354^.) 



TeJlurinm. — A(.'(!ordiiijj to Berthelot and h'ahrc tlic traiKsformaliou of 

 amori)li()ii.s ti'llniiuin into llio crystalliTn' variety is attended by an ab- 

 sorption of heat. In this partienhir it is tlie opi)osite of selenium. 

 Fabre finds that in its different modifications tellurium has sensibly 

 the same specific heat, Telluride of magnesium is easilj' ])repared by 

 lieating" magnesium in dry hydrogen, and passing over it an excess of 

 tellurium vapor. It is a wliite, flaky substance, which, treated with 

 acidulated water, yields telluretted hydrogen, and the latter gas is so 

 unstable as to decompose immediately in contact with moist air. Its 

 heat of formation is negative. A number of metallic tellurides were 

 prepared and studied by Fabre therino-chemically. Their heats of 

 formation were all ])ositive, but less than in the case of the corres])oud- 

 ing selenides. (Ann. Chim. Phys. (0), xiv, 93, llO.) 



Solution of iron in cansfio .soda. — When a strong current of air is 

 foiced into a hot, concentrated solution of caustic soda contained in an 

 iron vessel, or in which finely divided ferric hydroxide is suspended, 

 noticeable quintities of iron are dissolved without coloration. At 

 ordinary temperatures the liquid remains (;lear and colorless for sev- 

 eral days, but ultimately becomes turbid and <liscolored, depositing fer- 

 ric hydroxide. This coloi' or turbidity disappears ui)on heating. Zir- 

 nite, who describes the phenomenon, attributes it to the possible for- 

 mation of a sodium i)erferrate, NaF'e04. (Journ. Chem. Soc, LVI, 105; 

 from Chem. Zeitung, xii, 355.) 



Luteocobalf ])ermanganate. — This salt, with several of its derivatives 

 intermediate between it and the chloride or bromide of luteocobalt, is 

 remarkable for being violently explosi\'e, both upon heating and l)y 

 percussion. It forms many highly crystalline double salts of consider- 

 able stability. (T. Klobb, Ann. Chim. Phys. ((}), xii, 5.) 



Electrulytic prvi-ipitaiion of copper. — According to Soret, dilute solu- 

 tions of coi>pei', except with very weak currents, yield a spongy precipi- 

 tate of metal. The nature of the de])osit de[)eiuls not only on the in- 

 tensity of the electric current and on the coiuHMitration of the solution, 

 but also on the proportion of free acid which may be i)resent. The 

 electrolytic cojijier always contairis liy<lrogen, its amount dei)ending 

 ui)on the temi)eiature of the solution and its acidity. That hydrogen 

 is simply occludcnl, not combined; and it sometimes contains traces of 

 carbonic anhydiide and carbonic oxide. (Compt. Kend., cvn, 733.) 



New platinum ija.se.s. — Dr. II. Alexander describes a number of com- 

 pounds, analogous to the i)latosamines, in which hydroxylamine replaces 

 ammonia. The plalodioxamine, of which the chloride, PtCl2.4NIl30, 

 eorresi)onds to the chloride of Reiset's base, forms a large series of selts, 

 in which alkalies precipitate an insoluble hydroxide, Pt(()Il)i;.4:NIl30. 

 In this reaction the hydroxylaniine base differs from all the other plati- 

 num bases so far known. (Ann. Chem., ccxlvt, 239.) 



