formerly supposed io be Zeohle, &e 347 
neither of which could dissolve the whole of it. What resisted 
the two former acids was found to be silica. That which re- 
mained undissolved by the latter, was silica and sulphate of 
load. Evaporation of the latter solution, betrayed also the pre- 
sence of lime, in the state of sulphate. The nitric and muriatic 
solutions, on evaporation, deposited nitrate and muriate of lead ; 
and sulphuric acid dropped into them produced a small quan- 
tity of sulphate of lime. 
The nitrate and muriate of lead were decomposed by sul- 
phuric acid, and the lead reduced on charcoal. 
Ammonia precipitated what remained in these solutions, and 
redissolved a part of the precipitates, which agreed in properties 
with that substance before mentioned (2. ) ; the remainder was 
of a brighter yellow. But I could not bring the solution of it 
in nitric acid to crystallize. 
B. 
( 1. ) Some of the yellow crystals, which had not the slightest 
appearance of being contaminated with extraneous matter, were 
dissolved in sulphuric acid. Silica was separated ; and the pre- 
sence of lime and lead proved by the appearance of their 
respective sulphates. 
( 2. ) If sulphate of ammonia is dropped into a solution of this 
mineral in nitric or muriatic acids, no change takes place, im- 
mediately. But on evaporation, a yellowish crust is deposited, 
which is insoluble in water. A solution of carbonate of soda in 
water, boiled on it, becomes yellowish-brown, and the greater 
part of it is dissolved. The residuum, which is white, is reduced 
on charcoal to a globule of lead. What the carbonate of soda 
had dissolved was found to be oxide of uranium. Sulphuric 
acid alone , does not produce this deposited crust. 
