Dr. Hofmann on the Poly-ammonias. 311 



rived from 2 of ammonia, in which 2, 4 or 6 equivalents of hydrogen 

 are replaced respectively bv I, 2 or 3 equivalents of the bi-atomic 

 molecule ethylene ; and the formylia, acetylia and proi)yha oi M. 

 Cloez present themselves as mouethylene-diamine, diethylene-diamme 

 and triethylene-diamine. . 



I have 'endeavoured experimentally to solve this question, ilie 

 analysis of acetylia, which is remarkable for the definite character ot 

 its salts, appeared to promise an answer to it. 



When repeating the beautiful experiments of IM. Clocz, 1 had 

 occasion to confirm all the indications given by this able chemist, 

 re-'arding the formation of the bases derived from bibromide ot 

 ethylene. The analysis, however, furnished a discrepant result. 

 M. Cloez represents formyha by the formula 

 C2 H3 N, 

 when the hydrochlorate becomes 



C2H3N, HCl=C2H4NCi. 

 When considered as a di-ammouium compound, this salt has the 

 composition 



C, Hg N., 2HC1=C, Hio N. Clo=2C., H^ N CI. 

 The two formula; only differ by one equivalent of hydrogen. 

 The analysis of a magnificently crystallized hydrochlorate has 

 furnished me the following results : — 



Formula of M. Clouz— New formula— Analysis. 



C2H4NCI. C^HioN.Cls. Mean. 



Carbon.. .. 18-32 18-U4 l/'S/ 



Hydrogen.. G-10 7-51 7-5a 



Chlorine .. 54-19 53-38 53 17 



On preparing the free base by the action of hydrate of potassa 

 upon the hydrochlorate, I was surprised to find that this body 

 retains hydrogen and oxygen in the proportion in which they 

 exist in water, which cannot be separated by prolonged contact with, 

 or by repeated distillation over, anhydrous baryta. 



The analysis of the free base has given the following result :— 

 Formula of M. Cloez— New formula— Analysis. 



C2II4NO. C4H,oN2 0sj. Mean. 



Carbon.... 31-58 30-76 30-67 



Hydrogen.. 10-52 12-82 . 12-97 



Nitrogen .. 36-84 35-90 36-32 



These numbers appear to me in favour of the formula which I pro- 

 pose for formylia ; there remains but little doubt that acetylia and 

 propyha are analogously constituted. 



There remains yet to find the last term of the scries, the tetre- 

 thylene-diammonium compound. Up to the present moment I have 

 only established by experiment that the three lower bases are 

 l)0werfully attacked by bibromide of ethylene, a non-volatile com- 

 pound being produced possessing properties in every respect analo- 

 gous to the character of tetramethyl- and tetrethylammonium. 



If further experiments confirm the hypothesis which I have 

 advanced, the action of ammonia on bibromide of ethylene would 

 give rise to four compounds analogous to the bases which I have 

 obtained by the action of bromide of ethyle : — 



