425 



was fixed by the analysis of the pale-yellow, amorphous, almost inso- 

 luble platinum-salt, which was found to contain 



C H 2a N 4 Pt 4 Cl ia = [< C ' g^" j N 4 ] "d 4 , 4PtCl a . 



Although less intricate than the result of the reaction between am- 

 monia and dibromide of ethylene, the products obtained under similar 

 circumstances from ethylene-diamine present still considerable com- 

 plexity ; and the impossibility of separating the tetramines by distil- 

 lation, together with their rapidly diminishing faculty of yielding 

 crystalline compounds, render the investigation of these substances 

 rather difficult, more particularly since time, temperature, and even 

 relative proportion of the reacting compounds are apt to vary the 

 nature of the products formed. 



A simplification of these difficulties appeared to present itself by 

 adopting the method which had so greatly facilitated the study of the 

 bases of lower atomicity, viz. by examining the deportment of some 

 of the ethylated monamincs under the influence of dibromide of 

 ethylene. 



As a chemical theory expands and becomes more and more conso- 

 lidated, the interest attached to the individual compounds used as 

 scaffolding in raising the structure becomes less and less, diminishing 

 in fact in the inverse ratio of the number of the compounds which the 

 theory suggests. It thus became a matter of comparative indiffer- 

 ence, in what series and by what materials the construction of the 

 group of tetrammouium-compounds was attempted. Ethylamine and 

 diethylamine appeared to recommend themselves by their accessi- 

 bility. Owing to the greater simplicity of the reaction, I will first 

 mention the results elicited in studying the deportment of the di- 

 ethylated monamiue. 



Action of Dibromide of Ethylene upon Diethylamine. 



The reaction is rapidly accomplished, both in the absence and pre- 

 sence of alcohol. On opening the tubes after several hours' digestion 

 at 100, the liquid is found to be acid ; the powerful evolution of bro- 

 mide of vinyl, which is invariably observed, at once points out tho 

 existence, among the products of the reaction, of considerable quan- 

 tities of bromide of diethylammonium. In addition to this bromide, 

 the reaction of dibromide of ethylene upon diethylamine furnishes 



VOL. XI. 2 I! 



