Behaviour of Cliemical Compounds, 283 



and 11^ firo even diamagnctic. We must therefore assume 

 that in the latter salts the cobalt is combined in a quite differ- 

 ent manner from that in which it is in the ordinary cobaltous 

 salts or those analoo-ous to the ferric salts. Much rather mr 



^ 



these salts, exactly like the ferrocyanides, contain the cobalt 

 in a special scarcely magnetic group, while perhaps the cobalt 

 replaces a portion of the hydrogen of the ammonium. For 

 the first four salts Geuther * had put forth the opinion that 

 they were double salts which contained respectively, together 

 with one molecule of luteocobaltammonium sulphite, either 

 (1) two or (2) one molecule of cobaltic sulphite, or (3) with 

 one molecule of sulphite of roseocobaltammonium one molecule 

 of cobaltic sulphite, or, finally, (4) with two molecules of hy- 

 posulphate of luteocobaltammonium one molecule of basic 

 cobaltic hyposulphate. 



The formulae of the salts 1 and 4 would therefore have to 

 be multiplied by three, that of salts 2 and 3 by two. They 

 would contain (1) six, (2 and 3) four, and (4) six atoms of 

 cobalt; and their molecular magnetism would be respec- 

 tively:— (1) 88-8, (2) 104, (3) 92-4, (4) 1-92. The luteoco- 

 baltammonium sulphite (in analyzed formula I2NH3, C02 O3, 

 3SO2) ^nd roseocobaltammonium sulphite (IONH3, Cog O3, 

 3SO2), as well as the hyposulphate of luteocobaltammonium 

 (I2NH3, C02 O3, 2 S2 O5, H2 0), contain two atoms of cobalt 

 each. Since, further, the luteo- and roseocobaltammonium 

 salts are to be considered almost unmagnetic, the total magne- 

 tism of the double salts would fall to the cobaltic sulphite and 

 hyposulphate only. The magnetism of each atom of cobalt 

 contained in the latter w^ould accordingly be (1) 22*2, (2) 52, 

 (3) 46, (4) 0'48. But these atomic magnetisms deviate con- 

 siderably from one another ; only salts 2 and 3 could contain 

 a common magnetic group of atoms. At any rate the cobaltic 

 salt to be assumed as existing in the salts could not be consi- 

 dered after the analogy of the ordinary ferric salts, since then 

 the magnetism of the cobalt contained in them must be greater 

 than in the cobaltous salts (67'2). 



The yellow precipitates obtained by adding to neutral or 

 acid solutions of cobalt-salts nitrite of potass showed them- 

 selves by their magnetism to be essentially different from the 

 ordinary cobaltous salts, as well as from the first-mentioned 

 salts (1-3) ; and so did the nitrites of cobalt which at the same 

 time contained barium, strontium, or calcium (17, 18, 19). 

 The magnetism of the latter is nearly the same as that of the 

 so-called potassio-cobaltous nitrite precipitated from a neutral 

 * Jahresh. 1863, p. 267 5 Erdmaun's Journ. vol. xcii. p. 32. 



