o-oo 
ee a are, Fo 
: " 
157 
the yellow powder analyzed by Grouvelle. Dr. Kane finds 
that this powder always retains an equivalent of water, that 
its formula is Ho.No; +2 Hg,.0, and that the grey subnitrates 
which have heen noticed by some chemists, are impure mix- 
tures of black oxide and the yellow powder. Dr. Kane 
considers the nitrates of the black oxide of mercury to be 
thus related : 
First crystallized, = Hg».0.No;- 2Ho. 
Yellow powder, =HO.NO, + 2Hg.>.0. 
Second crystallized, = 2 No; +3 ug...0 + 3n0. A doublesalt. 
Great difficulty was found in determining what specimen’ 
of Hahneman’s mercury should be considered as pure and fit 
for analysis. Considering that the most important sources of 
error tend to throw the value of mercury too high, Dr. Kane 
derives his formula from the lowest number which he ob- 
tained by analysis, and these numbers were given always 
by the blackest and purest looking portions. He finds, 
on these grounds, for the ammonia subnitrate of the black 
oxide, the formula NH3.No; + 2 Hg.s.0. which is related to 
the water subnitrate in a similar manner to what holds in 
the corresponding compounds of the red oxide. 
Thus, in this paper, two propositions are developed: 
Ist. Increased evidence of the formation of metallic amides. 
Qnd. That ammonia as amide of hydrogen is capable of 
replacing oxide of hydrogen in its various functions in the 
quicksilver salts. 
Professor Apjohn read a paper “on the Properties of 
a new Voltaic Combination,” by Thomas Andrews M.D., 
Professor of Chemistry in the Belfast Institution. 
The object of the author in this paper is to extend the 
results which he has already obtained on the influence of 
voltaic circles upon the solution of the metals in nitric acid to _ 
the case of concentrated sulphuric acid. When a plate of - 
a 
