Physics and Chemistry. 131 
I have obtained very accurate results by a process differing al- 
eee from those described, but as simple as any. 
hen chlorid a ammonium and ammonia are added to a warm 
hlorid o 
ee ammonia are pres 
The following schapis wil show the mode by which I ope- 
rate 
12°6 6 grs. of pure sulphate of Dees MnOSO,+4HO, were 
gently ignited, and weighed 8-73 grs. =4°11 MnO. 6 grs. of oxyd 
of ery nay eve a trace of silica, were ignited and weighed 
then 5°6 ; these were dieatdred together i in hydrochloric acid 
and water. ‘an the solution diluted; it was made acid with hy- 
drochloric’ acid, phosphoric acid was atidal, and the whole heated 
me il near y poi ing: when ammonia was added in excess, a white 
bnlky precipitate was produced which rapidly contracted in vol- 
and became nuked eid after standing twelve hours it 
and wa i * f ammo- 
The € ammoniacal solution was treated my gph heirs hydrogen, 
and - sulphid converted into oxyd _— asting with a little car- 
bonate of ammonia. It we ighed 5°57 grs. 
Taken. Obtained. 
MnO <<. 6 0 3 42 4°33 
NiO - - - + 5°63 5°57 
I probably drove off a little sulphuric acid on igniting the sul- 
phate of mangan ae I have obtained more accurate results with 
the Ieeeis seid sin 
opera with, cobalt and manganese in the same manner, 
I obtained a a slight excess of manganese, and the salt was slightly 
3°22 grs. of oxyd of manganese, and obtained 3°15 gts. 
from dobiatt Phil Mag., IV, xvi, 197. 
