414 Transactions.— Chemistry. 
or oily matter which may be present in the solution to which such test is 
applied. This ean generally be accomplished by shaking such solution 
with a little pure hard fat, at its fusing-point, and removing the crust which 
forms on cooling. 
In conclusion, I would desire to point out to you that by some of the 
facts above stated may be explained that difference which has arisen between 
Reynoso and Schiff respecting the character of the precipitate produced by 
adding water to aleohol in which has long been dissolved mercuro-iodide ; 
the former has stated it to be red; the latter, to be yellow—a discrepancy 
which is readily susceptible of explanation upon the very likely assumption 
that in the case where such precipitate is yellow: an oil was present in the 
alcohol used. 
Art. LXVI.—On the Decomposition of Argentic-oxide by Mercury. By 
Witam Srey, Analyst to the Geological Survey Department. 
[Read before the Wellington Philosophical Society, 21st February, 1880.] 
Upon the authority of Fisher it is now supposed that argentic-oxide is not 
decomposed by mercury; but I find that, when these two substances are 
kept for some weeks in contact; whether in light or not, a considerable 
quantity of silver amalgamates with the mercury, and a crust of yellow 
mercuro-oxide is formed, demonstrating that this silver compound is di- 
vested of its oxygen by mercury, but at a very slow rate of speed. The 
same decomposition takes place if the two substances are kept immersed in. 
caustic potash. 
