^ Dr. Kane on the Compounds oj" Ammonia. 



developed in the present memoir ; the chlor-amidide of hydrogen, Hcl -\- Hxd, 

 and the chlor-amldide of mercury, ugcl -|- ugxd, being connected by the inter- 

 mediate chlor-amidide of mercury and hydrogen, ugcl + ha<^, 



I had remarked long since, that by the addition of sal ammoniac to the water 

 in which the real white precipitate is boiled, its decomposition, or at least the 

 formation of the yellow powder is prevented. The white precipitate remains 

 white, but its nature is totally altered ; it is converted altogether into the new 

 compound, and it will be seen that its composition would be represented, sup- 

 posing it to be formed by the union of the two substances which had been put in 

 contact, for 2 (ugcl.jiUs) = {ugcl.ugxd -f hc/.hac?). 



Such a mode of representing its nature would likewise explain its various 

 properties, but I prefer the view first described, and look upon this body as sim- 

 ply expressed by ugcl -f- ha</. I would propose for it the empirical name of 

 Woehler's white precipitate, and if one founded on composition be deemed ne- 

 cessary, that of the hydrargyro-chlor-amidide of hydrogen. 



A reaction which I have lately observed, and which as a remarkable property 

 of white precipitate, is worthy of being noticed, is, that when the chlor-amidide 

 of mercury is boiled with an excess of chloride of copper, it is totally converted 

 into sal alembroth, and there results brunswick green. The reaction appears to 

 be as follows : 



^ cud -^ Z {ugcl -{-ngkd) -\- 6ho = 2{cucl -\- Zcuo') -\- Z{2ugcl -\- i^ufil). 



In the sal alembroth thus produced the proportions of its ingredients are .diffe- 

 rent from those of the more common form : the sublimate containing twice as 

 much chlorine as the sal ammoniac. It is, however, quite definite, and can be 

 easily procured by dissolving together sublimate and sal ammoniac in the proper 

 quantities. It crystallizes in two forms, one rhomboidal, the other in long silky 

 needles ; in the former condition the salt is dry, in the latter it retains an equiva- 

 lent of water. Frequent analyses gave for their composition the formulae 



Rhomboidal state = 2h^c/-{- nh^c/. 

 Fibrous state = lugcl •\- su^cl -\- ho. 



The ordinary form being, as is well known, iigcl-\--su^cl-\- ho. 



