F. D, Adams—Chlorine in Scapolites. 319. 
that amount. In every case in which the sublimate was tested 
with barium chloride, a white precipitate was obtained. In the 
off, and the chlorine determined in the filtrate by precipitating 
with silver nitrate. The results were as follows :— 
y decomposition with hydrofluoric acid......... 1824 per cent. 
By fusion with sodium carbonate........ bs ey anee rie. % 
Difference....... ere ea dan bates & 068 
The loss is therefore very small. The scapolite from Ripon is 
not easily decomposed by sulphurie acid. In an experiment 
conducted by Mr. Comstock in this laboratory, two grams of 
the finely pulverized mineral were treated with concentrated 
sulphuric acid for three hours and a half at a temperature be- 
tween 160° and 200° C., but only a trace of chlorine was given 
off. Dr. Schafhiutl also states that at a red heat every trace of 
chlorine was expelled from his mineral, and that some of the 
chlorides were dissolved out by water. That such is not the 
Case with all scapolites is seen from the following experiments 
conducted on the same material from Ripon: ‘87 of a gram was 
heated to intense whiteness in a platinum crucible and fused 
down toa transparent, colorless, vesicular mass. It lost 5-178 
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