620 



These are, however, by no means the only salts which, in accord- 

 ance with our present conception of diatomic compounds, may be 

 formed in this reaction. Taking into consideration the general 

 deportment of dibromide of ethylene, there could be no doubt that, 

 under certain conditions, this body would act with ammonia as a 

 monoatomic compound, giving rise to another series of bodies, in 

 which the hydrogen would be more or less replaced by the mono- 

 atomic molecule C 2 H 4 Br, viz. 



[(C 4 H 4 Br)H 3 N]Br 



[(C 2 H 4 Br) 2 H 2 N]Br 



[(C 2 H 4 Br) 3 HN]Br 



[(C 2 H 4 Br) 4 N]Br. 



Further, if the reaction took place in the presence of water, it was 

 to be expected that the latent bromine of these salts, wholly or par- 

 tially eliminated in the form of hydrobromic acid, would be replaced 

 by the molecular residue of water, and thus, independently of any 

 mixed compounds containing simultaneously bromine and oxygen, a 

 series of salts might be looked for, in which a molecule C 2 H 4 (H0)= 

 C 2 H 5 O would enter monoatomically. 



[(C 2 H 5 0) H 3 N]Br 



[(C 2 H 5 0) 2 H 2 N]Br 



[(C 2 H 3 0) 3 H N]Br 



[(C 2 H 5 0) 4 N]Br. 



Lastly, remembering the tendency exhibited by ethylene-com- 

 pounds to resolve themselves in the presence of alkalies into vinyl- 

 products, it appeared not improbable that a fourth series of bodies 

 would likewise be formed, 



[(C,H.) H 3 N]Br 



[(C 2 H 3 ) 2 H a NJBr 



[(C 2 H 3 ) 3 HN]Br 



[(C 2 H 3 ) 4 N]Br. 



In the experiments on the action of dibromide of ethylene upon 

 ammonia, which I have already partly published, and which, in a 

 more connected form, I hope soon to lay before the Royal Society, 

 I have not, indeed, met with the whole of these compounds ; but in 

 the place of the deficient members of the groups new products have 

 made their appearance, whose formation in the present state of our 



