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SELECTED ARTICLES. 
and antimonic acids, are slightly soluble in water, more espe- 
cially at the boiling temperature. 
The solution of oxide of antimony does not deposit any 
thing on cooling. It reacts with sulphuretted hydrogen abso- 
lutely, like a feeble solution of arsenious acid ; it becomes of 
a clear yellow color, and if ammonia be then added, the color 
disappears, the solution being entirely colorless. The sulphuret 
of antimony formed in this instance, dissolves in the ammonia 
with the same facility as the sulphuret of arsenic. When I 
first noticed this property, I suspected it to happen from hav- 
ing used antimony containing arsenious acid, although I had 
used the process, recommended by M. Liebig, to obtain the 
purified antimony which I had employed. But having boiled 
the residual oxide in several successive portions of water, I 
obtained, each time, a liquid which produced, with sulphur- 
etted hydrogen, a yellow color of similar intensity. 
The constant reproduction of this color, sufficed to attribute 
it to the oxide of antimony, and not to arsenious acid. I never- 
theless repeated the experiment with pure oxide of antimony, 
extracted from tartar emetic, and of the purity of which I 
could have no doubt; the same appearances were reproduced. 
There is, therefore, an identity in the manner in which a 
weak solution of arsenious acid, and a solution of oxide of 
antimony react, when treated by sulphuretted hydrogen and 
ammonia; but, although similiar in certain characters, they 
differ much in others. While that of the solution of arsenious 
acid, in the apparatus of Marsh, gives brilliant metallic spots, 
the solution of oxide of antimony, submitted to the same test, 
furnishes black, tarnished spots, offering all the characters of 
antimony. 
The yellow liquid, obtained by causing sulphuretted hydro- 
gen to act upon a weak solution of arsenious acid, left to itself, 
deposits a canary-yellow powder, (sulphuret of arsenic;) the 
yellow liquid, from oxide of antimony, will deposit, by the 
next day, orange-yellow floculi, easily recognised as sulphuret 
of antimony. The sulphuret of antimony is separated, imme- 
