on the Ammonia-cobalt Bases. 255 
se with the mass of liquid from which they are thrown down. 
hey are more distinct in form the more slowly the precipitation 
takes place. The salt has the forraula 
5NH3.Coz Cy 3 +Co2Cys +38HO. 
as the following analyses show: 
01924 grs. (from chlorid of Purpureocobalt) gave 01540 grs. sulphate of cobalt 
= 80°46 per cent cobalt. 
07150 grs. (from chlorid of Roseocobalt) gave 05755 grs. sulphate of cobalt = 
‘63 per cent cobalt. 
#08111 grs, (from chlorid of Roseocobalt) gave 272 c. c.of nitrogen at 10° O. and 
761™™-99 (at 10° C.) = 259-48 cc. at 0° and 760™™ = 40-18 per cent. 
The formula requires 
Eqs. Calculated. Found, 
Cobalt, - - 4 8057 30 68 3046 
Nitrogen, - - 11 89°89 40-18 
_ The analyses of the ferrideyanid of Roseocobalt bh addi- 
sc evidence of the gorrectness of the formula ac opted for 
this salt. 
FERRIDCYANID OF ROSEOCOBALT. 
The ferrideyanid is formed like the ange i: by ae 
j ne r 
4 solution of ferridcyanid of potassium to one of chlorid or n1- 
tra 
f the corres 
The crystals exhibit a remarkable dichroism, the ordinary image 
being of a fine purple rose color, while the inka A image 
ge rok water; 
the sal, by that anceepadty it by heat, then burning off the 
carbon in a gentle current of oxygen, and finally reducing aa 
nixed oxyds of cobalt and iron in a current of hydrogen. © 
formula of this salt is 
5NHs3.Co2Cys +Fe2Cy: +3HO 
48 the following analyses show: 
03618 grs, gave 0-1086 ors, metallic iron and cobalt = 30°05 per cent. 
sites <5 burnt wit okyd of copper and oxygen, gave 1:0302 gre. carbonic 
= 1869 per cent carbon. 
The 
tem sles Eqs. Calculated. Found. 
Cobalt and i . 30-02 ~ 30-05 
Calbia es ed! cas 1879 1869 
