254 W. Gibbs and F. A, Genth — 
OXALATE OF ROSEOCOBALT. 
The oxalate is precipitated from the chlorid almost immedi- 
ately by the addition of a solution of oxalate of ammonia. From 
a solution of the nitrate it is deposited much more slowly, often 
only after some hours, and sometimes in remarkably distinct and 
well formed crystals. The oxalate as first thrown down may be 
purified by solution in ammonia-water and recrystallization by 
spontaneous evaporation. The salt then forms beautiful prs- 
rhombic prism of about 101° 48’, with a brachydome of 108° 54’. 
The constitution of the oxalate of Roseocobalt is represented 
by the formula 
5NHs.Co20:s, 80203+6H0 
as the following analyses show: 
0°5504 ers. gave 0°2625 ers. sulphate of cobalt = 18:15 per cent. 
0°3325 grs. gave 01585 grs. 3 f: rat Te “ 
15381 grs. gave 06170 grs. carbonic acid = 32-82 per cent oxalic acid. 
The formula requires 
Eqs. Calculated. Found. 
Cobalt, - - z 17°87 18°15 18°14 
Oxalic acid, - - 3 32-73 82 82 
COBALTIDCYANID OF ROSEOCOBALT. 
_ This beautiful salt is precipitated from a solution of the chlo- 
rid or hydrous nitrate of Roseocobalt, by a solution of cobaltid- 
into a salt of the triacid Roseocobalt. The cobaltideyanid is 
merean precipitated at once in the form of cherry-red prismatic 
crystals, which, so far as it is possible to judge from their ap- 
el gee from the sulphate of Roseocobalt only after 
The crystals are usually remarkably large when com 
