98 RESEARCHES ON THE AMMON1ACAL COMPOUNDS. 
nia and mercury, or that, being decomposed, amidogen unites? 
with a portion of the mercury, and forms an amidetof mercu- 
ry, which unites with the chloride already present, to produce 
the white precipitate. The following formula will show these 
two modes of decomposition ; but in the former instance it is 
necessary to consider the water present as taking part in the 
decomposition, while in the latter it may be entirely neg- 
lected. 
2Cl 2 Hg+4NH 3 +4H0^2(ClH J NH3)+2(ClH,Hg0 2 ,NH 3 ) 
2Cl*Hg+4NH 3 =2(ClH,NH 3 ) + (Cl 2 Hg+Hg2NH 2 ) 
In the first, four equivalents of ammonia, and four equiva- 
lents of water, acting on two equivalents of bichloride of mer- 
cury, there results two equivalents of muriate of ammonia and 
two equivalents of muriate of ammonia and deutoxide of mercu- 
ry ; and in the second, omitting the water, we have the two 
equivalents of bichloride and the four equivalents of ammo- 
nia mutually reacting with decomposition of half of each, two 
equivalents of the chlorine of the bichloride uniting with two 
equivalents of the hydrogen of the ammonia, to form hydro- 
chloric acid, which unites with the remainder of the ammonia 
to form the muriate of ammonia, and there is left one equiva- 
lent of undecomposed bichloride of mercury and one equivalent 
of metallic mercury, with two equivalents of amidogen, to 
unite and form the biamidet of mercury. 
To ascertain to which of these views we should give cre- 
dence, it is necessary to resort to the results of analysis. 
Here we are at once met by the discrepant statements which 
are given by the different chemists who have examined this 
preparation, — the mercury varying from 74 to 82 per cent., 
and the chlorine and ammonia in like proportion. To account 
for this, it is only necessary to consider how readily the salt 
is decomposed by hot water, and even by cold water, when 
used in large quantity,™ also that as two methods are usually 
directed to obtain this preparation, the results of which are 
somewhat different in composition, the substance analysed 
would necessarily afford different proportional results. 
