88 C. A. Joy on Glucinum and its Compounds. 
admirable, and is highly recommended for the decomposition of _ 
other silicates. The yield of glucina was not ee equal to that 
obtained for the fusion with carbonate of potassa 
10. Binoxyd of manganese.—Two parts of finely pulverized 
f 
yerize. It was digested in concentrated seine acid, and 
silica sagan as usual. "The beryl was fully decom : 
object was to see whether the binoxyd of manganese would de- e 
compose silicates in this way, and, further, to try if an alum with — 
the protoxyd of manganese (MnO, SO,+Al 0, 390, +2410) — 
could be formed. No such alum was obtained, “thus confirming : 
separation of alumina and glucina, that this method was pre 
ferred to any other. 
All of the above methods, and numerous others which it 
not necessary to recapitulate, were subjected to repeated trials 
in my laboratory, and a large supply of glucina obtained fo 
use in the further prosecution of this investigation. Z 
Methods for the separation of glucina and alumina. 
1. Chlorid of ammonium. 7. Decomposition of nitrates. 
2. Carbonate of ammonia, 8. Acetate of soda. 
8. Caustic potassa. 9. Fusing with caustic potassa. 
4. Sulphurous acid. 10. Formate of ammonia. ; 
5. Carbonate of baryta. | 11. Decomposition of sulphates. 
Hyposulphite of soda. | 12. Potash alum. 
: she: By chlorid of ammonium.—The oxyds of che sn 
and glucina were fio) Sth by ammonia, and t ecipita 
digested in a concentrated solution of chlorid of ammon 
with constant roplacetaandt of the oA teen water, The 
and alumina, being insoluble in sal-ammon collected 1 
a filter, and the giucina precipitated from the filtrate by sw. 
Ae jum. 
This method, proposed by Berzelina,* was. regarded by We 
ea on teers tugs toy at heen ah 
