on the Ammonia-cobalt Bases. 325 
The fact that the ammonia unites with both sulphurie and 
oxalic acid, and not simply with éwo equivalents of oxalic acid, 
throws much light on the constitution of the acid‘oxalo-sulphate, 
and — we think, clearly that the formula of this salt can- 
not 
5NHs.Co202, 2803+2020s, HO+HO. 
The constitution of the neutral oxalo-sulphate is represented 
by the formula 
5NHs.Co20s, }Os0s+7HO 
a8 appears from the following analyses: 
_ 06367 ers. gave 0°8217 grs. sulphate of cobalt = 19°23 per cent cobalt. 
06721 grs. gave 0-2569 gts. sulphate of baryta = 13:12 “ sulphuric acid. 
99760 grs. gave 191 ¢.¢. nitrogen at 17°25 C. and 767™™58 (at 1798) = 
177-43 ¢.¢, at 0° and 760™m == 22°83 per cent. : : 
The formula requires 
Eqs. Calculated. Found. 
Vonage 19°21 19°23 
Sulphuric acid, - - 1 13°02 13:12 
Oxalic aci - « 1 11°72 
Nitrogen, - - ~- 5 22°80 29-83 
“ach other in combinations. 
OXYD OF PURPUREOCOBALT. : 
The oxyd of Purpureocobalt, like that of Roseocobalt, appears 
to exist only in debasson It may be prepared, either by decom- 
Posing the acid sulphate by baryta water, or by digesting a solu- 
hon of the chlorid with oxyd of silver in the cold. The solution 
Solution, forms a violet-red liquid, which absorbs carbonic acid 
-Teadily from the air, and which is decom by concentration. 
be 
Tadical, ap 
is essentially biz 
