| * 
82 M. C. Lea on New Combinations of — 
Heated on platinum foil the ammonia picrate of copper ex- 
plodes with some violence and with a dazzling light. 
Ammonia-picrate of Cobalt. 
To a solution of protochlorid of cobalt prepared from chlorid 
of purpureo-cobalt in the manner recommended by Gibbs and 
Genth in their interesting and valuable paper on the ammonia- 
cobalt bases, a large excess of ammonia was added, and to the fil- 
trate, cold saturated solution of picrate of ammonia. An abund- 
ant highly crystalline precipitate falls at once, which after dry- 
ing is yellowish green: while moist decomposes with great 
facility with separation of cobaitous ox 
“6293 substance gave °4784 picric acid. 
"607 5 oc “ . 6c “ 
6067 - “+1641 protosulphate of cobalt. 
*5416 “ “ *1475 “cc 6 “ 
6075 % “ +2065 chlorhydrate of ammonia. 
which results lead to the formula :— 
es H 
@NH,C0O0.C12 snd), bo+HO. 
Calculated. Found. 
1. , _ Mean. 
Ogg Ny Ous 75°87 75°69 75:29 75°49 
Co 9°82 10°13 10°29 10°21 
2NH, 11°32 10°81 10°81 
HO ee 2°99 
100°00 
Ammonia-picrate of Zinc. : die 
To a solution of pure sulphate of zinc, chlorhydric acid was 
added in sufficient quantity to prevent precipitation by the sub 
