Analyses of the Chrysoberyls from Haddam and Brasil 1 ll 
tated from it. The matter precipitated by the subcarbonate 
of ammonia consisted of 3.68 grammes of alumina, or 73. 
60 per 100., and 0.19 grammes of peroxide of iron, which, 
on account of the colour of the mineral, must be estimat- 
ed as protoxide. The 0.19 grammes of peroxide are 
equivalent to 0.169 of protoxide, or 3.38 per 100. 
THE CONSTITUENTS OF THIS CHRYSOBERYL THEREFORE ARE 
(Per 100 parts) 
A. Moisture 0.40 
C. Oxide of titanium 1.00 
D. Glucina  — 15.80 
By Silica OF; 4.00 
F. Alumina 73.60 
_F. Protoxide of iron 3.38 
98.18 
100.00 
As the preceding results differed so essentially from the 
analyses of the chrysoberyl from Brazil by Klaproth and 
Arfwedson, I determined to examine a specimen from that 
locality. 1.5 grammes were analysed, in the manner above 
mentioned, and the following results were obtained :— 
(Per 100 parts) 
Water 0.666 
Oxide of titanium 2.666 
Glucina 16.000 
Silica 5.999 
Alumina - ‘ 68.666 
Protoxide of iron 4.733 
98.730 
100.000 
Loss 1.270 
