1863.] 381 



monium is very small when compared with the quantities of the 

 iodides of methyl, trimethyl, and more especially of tetramethylam- 

 monium, not to speak of iodide of ammonium itself, so that I was 

 compelled to be satisfied with approximative platinum determina- 

 tions in order to establish the formation of dimethylamine under 

 these circumstances. Having lately had to prepare a specimen of 

 the dimethylated ammonia, and remembering the small quantity 

 which is formed by means of iodide of methyl, I resolved to avail 

 myself of an observation made in the mean time, according to which 

 dimethylamine is formed by the action of soda-lime upon the sulphite 

 of aldehyde ammonia, 



C 2 H 4 , H 3 N, S0 3 + Ca 2 0=C 2 H 7 N + Ca 2 S0 4 . 



According to M. Gossmann*, this reaction furnishes ethylamine, 

 and indeed in such quantities as to render this process a convenient 

 mode of preparing the substance. Re-examined subsequently by 

 M. Petersenf, the ethylamine of M. Gossmann proved to be di- 

 methylamine, which is isomeric with the former, 



C 2 H 5 ] CH.1 

 C 2 H 7 N= H lN=CH 3 IN. 

 H J H J 



Nor does M. Petersen appear to share the enthusiasm of his pre- 

 decessor for the facility and elegance of this reaction. Indeed, a glance 

 at the analysis published by this chemist is sufficient to show how 

 small a quantity of the base produced by this process must have been 

 obtained. 



In repeating this experiment, I have indeed obtained a minute 

 quantity of an inflammable ammonia ; but, though varying the pro- 

 cess, and working on a tolerably large scale, I was unable to procure 

 a sufficient amount for a single analysis. 



Under these circumstances I was compelled to return to the reac- 

 tion by which I had originally obtained dimethylamine, viz. by the 

 action of iodide of methyl upon ammonia. 



By availing myself of the method of separating the ethyl-bases, 

 which some time ago I submitted to the Royal Society J, I succeeded 



* Ann. Chem. Pharm. vol. xc. p. 122. 



t Ibid. vol. cii. p. 317. 



| Proceedings of the Royal Society, vol. xi. p. 66. 



