Dr. Kane on the Compounds of Ammonia. 83 



During the examination of the various classes of compounds of ammonia, 

 which the objects of these researches rendered necessary, a variety of results were 

 obtained, which are calculated to throw light on the relation in which the ammo- 

 niacal salts stand to the ordinary basic salts of the same acid, and likewise to 

 illustrate the connexion between the corresponding so called neutral and basic 

 salts. In the cases of the nitrates of mercury, my observations have the effect of 

 extending to that metal the law discovered by Graham for the nitrates of the 

 metals of the magnesian class, but as that distinguished chemist has not deduced 

 any general idea of the constitution of the basic sulphates from his observations, 

 I shall briefly suggest such ideas as have occurred to me from my own investi- 

 gations. 



The general principle that the transition from the neutral to the basic con- 

 dition in salts takes place by the replacement of water by metallic oxide, has, as 

 I conceive, received the fullest confirmation ; but I do not consider that the cor- 

 responding substitution of water for metallic oxide, which exists so markedly in 

 the sub-nitrates of copper and bismuth can be looked upon as forming a general 

 law. Thus there certainly does not appear the same perfect symmetry between 



ho.no3 4"3h^o and Hg-o . N05-j-Hg-o + 2Ho 



as between 



cwo . NO3 -{- 3ho and ho . no^ -j- 3cmo ; 



and although I do not possess absolute proof of the existence of a sub-nitrate 



formula is that which Hartwell has established. According to his analyses, lime and soda replace 

 one another in indeterminate proportions, and are consequently placed in the formula under one 

 another, as isomorphous bodies, although there is not as yet known any positive example of the 

 isomorphism of lime and soda. The sulphate of soda or thenardite does not appear to be isomor- 

 phous with anhydrite, and the analyses of mesotype by Gehlen and Fuchs, show perfectly that lime 

 and soda may replace each other, but that in this case, the quantity of water in the compound 

 also changes, so that one atom of soda can be isomorphous only with an atom of lime -\- an atom of 

 water, which must consequently be assumed in all other zeolites where lime and soda appear to re- 

 place each other, as, for example, in the chabazies." It is singularly interesting to find, that starting 

 from an origin apparently so remote as the composition of white precipitate, I have been gradually 

 conducted to the development of the same principle as had already, though unknown to me, been 

 announced, even though but as a suggestion, by an authority so deservedly high in chemistry and 

 mineralogy as Gustav Rose. 



M 2 



