246 W. Gibbs and F.. A. Genth 
amination to the second part of our memoir. The reactions of 
the chlorid of Roseocobalt are as follows: 
Terchlorid of gold gives no precipitate-at first, but after stand- 
ing a lilac or purple precipitate, which is probably merely the 
chlorid of Roseocobalt. 
Bichlorid of platinum gives a pale orange red precipitate. 
Chlorid of mercury gives a pale rose or flesh-colored flocky 
precipitate. 
Ferrideyanid of potassium gives beautiful orange-red oblique 
rhombic crystals. 
Cobaltidcyanid of potassium gives fine red crystals. 
Ferrocyanid of potassium gives a cinnamon, passing to a choc- 
olate brown precipitate. 
Oxalate of ammonia gives a brick-red precipitate of small 
- granular crystals. 
Neutral chromate of potash gives no precipitate. 
Bichromate of potash gives a dark brick-red precipitate. 
The following reactions, which were obtained with a solution 
of the irpdated nitrate of Roseocobalt may also be introduce 
in this place. 
yrophosphate of soda gives a dull rose-red precipitate soluble 
in an excess of the precipitant to a clear red liquid, which in @ 
few minutes solidifies to a mass of fine rose-red needles. 
Picrate of ammonia gives a fine bright orange red precipitate 
soluble in hot water. 
Todid of potassium gives no precipitate either with the chlorid 
or nitrate. ere 
The precipitate with chlorid of mercury is readily soluble 1n 
chlorhydric acid, and the solution after standing gives beautiful 
small granular crystals of a brownish red. color. 
The reactions which are peculiar to the sulphate of Roseoco- 
balt will be described when speaking of that salt. 
SULPHATE OF ROSEOCOBALT. 
An ammoniacal solution of sulphate of cobalt absorbs oxygen 
readily from the air, becoming at first brown and then dark red. 
decompos 
_ The sulphate of Roseocobalt is, however, not always the only 
salt formed under these circumstances. In some cases in which 
the ammoniacal liquid was allowed to stand several months until 
