'278 Dr. Hofmann on [May 16, 



mine, diet/it/ fa mine, and triethylamine : and the composition of 

 which is illustrated by the following formulae : — 



The three ethylated derivatives fully retain the fundamental 

 character of ammonia ; they are powerful bases, capable of uniting 

 with the acids, and of forming very definite, well-crystallizing salts. 

 Owing to the diminution of volatility with the progress of ethyla- 

 tion, the ethylated bases appear to be even more powerfully basic 

 than the type itself. This development of basic power, as will be 

 presently seen, deserves especial consideration. The substitution 

 of ethyl for hydrogen presents no difficulty, it may be effected by 

 several methods, one of the commonest processes consisting in 

 the action of iodide of ethyl upon the body to be ethylated. 

 Thus ammonia and iodide of ethyl produce ethylamine and 

 hydriodic acid, which unite and give rise to the formation of 

 hydriodate of ethylamine.* 



Nm + EI = N H} HI, 



In consequence of the ethylated derivatives of ammonia retain- 

 ing the basic character of the type, and exhibiting it, under certain 

 conditions, even in a higher degree, the question naturally suggested 

 itself, What would be the effect of introducing ethyl into phospho- 

 retted, antimonetted, and arsenetted hydrogen ? 



The ethylation of these hydrogen-compounds presents difficulties 

 not experienced with the nitrogen-series, and has been accomplished 

 only by roundabout processes. Nor have all the terms, the exist- 



♦ Ammonia, ethylamine, diethylamine, and triethylamine placed side by 

 side ; the alkaline properties of these four substances experimentally demon- 

 strated. Iodide of ethyl, and its action on ammonia exhibited. 



