Dr. Kane on the Compounds of Ammonia. 69 



tions, and one of the most embarrassing circumstances in the present investigation 

 arises from the fact of the relation of ammonia and water being so close, that 

 where the ammoniacal bodies are soluble in water, they cannot be brought into 

 contact with it without an exchange of position occurring to a considerable ex- 

 tent, and the body crystallizing in a state containing both water and ammonia. 

 Thus, whilst by passing dry ammonia over chloride of copper, the body 

 cmc^-|-3nh3 may be obtained, the result of treating a solution of chloride of 

 copper by ammonia is CMc/-t-2NH3-l-HO, in which the third equivalent of 

 ammonia has evidently given place to one of water ; and though the copper, as I 

 have already shown, is separated from the chlorine, however by means of heat 

 both bodies yield cwc/NHg; the one losing 2NH3, the other H0.NH3. Thus, 

 through the whole class of soluble ammonia-copper and zinc combinations, the 

 water replaces, in the first instance, the metallic constituent, and partly the am- 

 monia itself, and it is only when by the application of heat the water with some 

 ammonia has been expelled, that we arrive at the real combinations of the 

 metallic compound with amidide of hydrogen. 



The basic nitrates of mercury being insoluble, furnish one of the most 

 striking examples to be found of the replacement of water in its basic condition 

 by ammonia. It was proved that the basic nitrates stood in the same relation to 

 the neutral salts as that which Graham had pointed out for the nitrates of the 

 magnesian class; and I showed, in the same section, that the ammonia sub- 

 nitrates were so constituted, that the nitric acid and oxide of mercury remained 

 the same, whilst the water of the ordinary sub-salts was replaced by the ammonia 

 thus : kd representing nh^. amidogene. 



The yellow sub-nitrate of the red oxide is 



HO.NOj-f-SH^O. 



The ammonia sub-nitrate of the red oxide is 



hac?.no5-}-3h^o. 

 The sub-nitrate of the black oxide is 



HO.NO^-^- 2Hg-o. 



The ammonia sub-nitrate of the black oxide is 



hac?.no5-|-2h^o. 



