= ay) 
-* 956 C. E, Avery on the Nitrate of Silver Test. 
tions. At the suggestion of Prof. F. H. Storer, I have tested 
this idea by experiment, 
All acids which I have tested in this regard exert some solvent 
power; but those having very little solvent action may be 
x 
2 
ment, that the addition either of acetate of sodium, acetate 
of ammonium, or Rochelle salt, to a mixed solution of arsenic 
and nitric acids, is sufficient to ensure the immediate precipita- 
tion of arsenate of silver, when ammonio-nitrate of silver is 
introduced. 7 i 
By placing a small quantity of a nitric acid solution of ar- 
senic acid 
‘Upon an excess of freshly precipitated carbonate of silver, or 
_ Ted arsenate, instantly formed, shows clearly on the ground 
8now-white carbonate ; this is a striking reaction, and there- 
fore a delicate test, Oxyd of silver, when tried in a like mal- 
ner, gave no results of value. j off 
a viments made with sulphate, succinate, and nine’ 
ammonium, served merely to establish the superiority of the 
Acetates and carbonate, as above described « 
ne ae ent in relative] la uantity, arsenic acid re 
precipitates silver from asclutie of nt id 
8 to the succinate of ammoni 
experiments were varied by changing 
