156 



the yellow basic nitrate, the oxide of hydrogen being replaced 

 by the amide of hydrogen. Thus 



nh 3 =. nh 2 .h == Ada. 



HO.NO5 + 3HgO. 

 HAG?.N0 5 + SHgO. 



This view is remarkably corroborated by the fact, that 

 when a solution of nitrate of ammonia is poured on the yellow 

 basic nitrate, the white powder is formed, while nitric acid is 

 set free. Another remarkable case of combination is shewn 

 by comparing the powder formed by boiling the white preci- 

 pitate with two of those described in this paper. Thus 

 there are 



ng.cl + 2ngo + HgAd. 



Hg\S0 4 + %HgO + HgAd. 

 Hg.NO e + 2llgO + HgAd. 



To which may be added, the oxychloride 

 Hg.cl + ^ Hgo + Hg-o- 

 When the white ammonia subnitrate is boiled with solu- 

 tion of ammonia, it dissolves, and a crystalline substance is 

 deposited of a very interesting nature. Its formula, by ana- 

 lysis, is 



3 (NH4O.NO5) + 4Hgo, 



But the circumstances under which it is formed rather in- 

 dicate for its rational formula the following : 



(Hg-N0 6 + 2 HgO ■+• HgAd) + 2 (NH4O.NO5) -\-2 HO. 



George Mitscherslich had already obtained a compound 

 of a similar nature, being 



NH3NO5 + 2 ago = (Hg-N0 6 + 2 ago + HgAd) + nh 4 o.no 5 . 



Passing to the nitrates of the black oxide of mercury, 

 Professor Kane has verified the analysis of George Mits- 

 cherslich, of the two crystallized protonitrates ; he then shews 

 that there exists one definite subnitrate of the black oxide, 



