90 W. Gibbs and F, A. Genth 



tion in the case of organic compounds containing NO 4. For 

 the same reason we also boiled the chlorid with acetic acid and 

 iron filings, in the hope of obtaining a reaction analagous to that 

 which is produced under the same circumstances with nitro- 

 benzol, nitro-naphtalin, ^c, as observed bj Bechamp. The ex- 

 periments, however, led to.no interesting result. 

 Chlorid of Xanthocobalt has the formula 



N02.5NH3,Co20, CU+HO, 



as the following analyses show : 



L 



0-2652 grs. gave 0'155*I grs. sulphate of cobalt = 22*34 per cent cobalt. 



0-5865 grs. gave 0*3435 grg. " . *' = 2229 •• « 



0-8240 grs. gave 8980 grs. chlorid of silver = 26*94 " chlorine. 



1-5200 grs. gave 1 6740 grs. " " = 27*22 * " 



0*4983 grs. gave 0*2773 grs, water =6-18 •* hydrogen. 



0-5897 grs. gave 0'3272 grs, " = 6-16 " 



10763 grs. gave 297 c. c. nitrogen at 16°-9 C. and 758«'"-43 (at 17^-2 C.) = 273*02 



c. c. at 0° and 760^'^ = 31*84 per cent. 

 a-0657 grs. gave 297 c. c. nitrogen at 19^*5 C. and 763"*'«'26 (at 20*^ C.) = 271-30 



c. c. at 0^ and 760'"'" = 31*97 per cent. 



The formula requires 





Eqs. 





Calculated, 



Mean. 



Cobalt, 



2 



59 



22-62 



22*32 



Clilorine, 



2 



71 



27-09 



2708 



H^' drogen, 



16 



16 



6-10 



617 



N itrogen, 



fi 



84 



S2'06 



31'90 



Diygen, 



4 



32 



12'23 



12'5S 



Found. 



22*34 



22*29 



26-94 



27-22 



6 18 



6'16 



31*84 



31"97 



2G2 100-00 



CHLOEAURATK OF XANTHOCOBALT, 



This salt is readily formed bj adding a solution of tercLlorid 

 of gold to one of the chlorid of Xanthocobalt. Beautiful yel- 

 low needles are thrown down, which may easily be purified by 

 re-solution in hot water and crystallization. The chloraurate of 

 Xanthocobalt crystallizes in beautiful brown-yellow iridescent 

 prisms, which belong to the trimetric or right rhombic system, 

 according^to Prof Dana's measurements. The observed forms 

 are O), 1-^ , the only observed angle is It: 11^ 180° 2'±\ 7 : / 

 varies much and could not be accurately determined. 



The formula of this salt is^ 



KO2.5NH3.C02O, Cl2-f AuCl3+2HO, 



The data of the analysis are as follows : 



2687gr9. gave 01645 grs, rnl^tallic gold and sulphate of cobalt = 1028 per 



cent cobalt. 



\, 



0-3028 grs. gave 0-1035 grs. metallic gold (reduced by SO2) = 3418 per cent. 

 G-2749 gra. gave 0-3461 grs. chlorid of silver = 31-12 per cent chlorine. 



The formula requires 



Eqs. Calculated. Found. 



Cobalt, - - • 2 10*26 10-28 



C^oH • - - 1 34-28 34-18 n 



Chlorine, - - . 5 30*89 81'12 



