846 Transactions.—Chemistry. 
upon which my opinion was founded, and with such modification as I 
thought might best conduce to results informing us correctly on this subject. 
Taking three plates of pure silver, which had been thickly enfilmed with 
this sulphide, by twent?-four hours immersion in a strong solution of sodic 
sulphide, I well washed and thoroughly dried them, but without disturbing _ 
these films ; then placed them gently on each other, and connected the out- 
side ones with a feeble battery of one cell, which was attached to a galvano- 
meter, when I found an electric current was still indicated, and which was 
not notably less in quantity than that which was indicated when these plates 
were out of the circuit. 
The same result followed when the silver plates were heated to 300° F. 
and even used in this experiment while at a temperature approximating to 
this. 
I, therefore, conclude that Argentic Sulphide can be, as I have main- 
tained, a conductor of electricity, and, for a sulphide, a very good one. 
Regarding the chemical deportment of this substance (Argentic Sul- 
phide), I find, contrary to what is alleged respecting it, that it is soluble in 
cyanide of potassium, and at common temperature, and I may state in this 
connection that aurie sulphide is also soluble in this salt ; platinic sulphide 
appears scarcely so, even in a hot solution of it, though sulphur is detect- 
able in this solution afterwards by the nitro-prussic test. 
I further find that Argentic Sulphide is not, as heretofore supposed, un- 
attacked by mercury, but is decomposed, though very slowly, by it, mer- 
curic sulphide resulting, attended by amalgamation of the silver thus 
liberated. Auric sulphide is also very slowly decomposed in the same way ; 
plumbic sulphide, however (as galena), is not. 
It will be seen, therefore, that these sulphides in their deportment with 
mercury behave exactly as we should expect from the electrolytic results I 
have given in respect to them in my paper on the Electro-motive Power of 
Gold and Platina in Sulphides,* both silver and gold being there stated to 
be negative to mercury in sulphide of sodium, and lead positive thereto. 
Indeed I may state that it was the knowledge of the elytrolytic behaviour 
of the metals above named which induced me to try for the decomposition 
of argentic and auric sulphide by mercury. 
In this connection I would further inform you that this sulphide (argen- 
tic) appears decomposed by chloride of copper alone, although it is stated 
not to be affected by this salt, except in the presence of an alkaline chloride. 
Theoretically, indeed, it should be decomposed by this auric salt unaided, 
as sulphur has a greater affinity for copper+ than it has for silver, and 
* «Trans. N.Z. Inst.,” Vol. IV., Art. LI. f+ Ibid. 
