110 Analyses of the Chrysoberyls from Haddam and Brazil. 
potash, and treated with diluted muriatic acid, with the fol- 
s 
lowing results : 
After the 2d experiment, it weighed 0.97 grammes. 
3d 0.89 
By the fifth treatment it was not diminished, and then 
presented itself in the form of a light white powder, re- 
sembling pure silica in appearance. 
C. The residue (B) was repeatedly strongly calcined 
with six parts of nitrate of barytes, and subsequently boil- 
ed with nitric acid. 
After the Ist treatment, there remained 0.43 grammes. 
2d 0.15 
3d 0.06 
And by the 4th operation only 0.01 gramme was dissolved. 
The remaining 0.05 grammes were essayed in the man- 
ner related in the preliminary experiments, and thus proved 
to be oxide of titanium. Hence we have 1. per 100 of 
that oxide. 
D. The nitric solutions were united and evaporated to 
dryness, to expel the excess of the acid. The saline mass 
was dissolved in water, and after the barytes was separated 
with sulphuric acid, an excess of subcarbonate of ammonia 
was added to the solution. An abundant precipitate ap- 
peared, which entirely re-dissolved. The Glucina was 
precipitated by ebullition. After edulcoration and calci- 
nation, it weighed 0.79 grammes, or 15.80 per 100. 
E. The several muriatic solutions (B) were united and 
evaporated to a dry mass, which was treated with muriati¢ 
acid, and there remained 0.33 grammes of silica, from 
which deduct 0.13 grammes acquired from the agate mor- 
tar ; and there will be 0.20 grammes, or 4. per 100 as 4 
constituent of the mineral. 
F. After the silica was separated from the liquid (E;) 
the alumina and oxide of iron, were precipitated by means 
ofa great excess of subcarbonate of ammonia. After twen- 
ty-four hours, the liquor was separated from the yellowish 
precipitate, and was boiled, but no glucina was precip! 
