225 



which M. Cloez* had published in 1853. The repetition of these ex- 

 periments compelled me to contest not only the formulae of M. Cloez, 

 but also the general interpretation which he had given to his results. 



I have not hesitated to communicate my conclusions to the Royal 

 Society-}*. 



M. Cloez J shortly afterwards discussed my observations, and 

 pointed out the arguments which induced him to maintain his 

 formulae and his interpretations. 



I have not replied to these remarks. M. Cloez having stated in 

 the same note that he was still engaged with his experiments and 

 that his inquiry was nearly completed, I discontinued my experi- 

 ments on the action of dibromide of ethylene upon ammonia, fully 

 persuaded that the chemist, to whom we are indebted for the first 

 observation of this reaction, in continuing his experiments would 

 arrive at the same results which I had myself obtained. 



In discontinuing the discussion with M. Cloez, I was not freed 

 from the obligation of proving the general thesis of my note, viz. 

 the formation of diatomic bases by the action of diatomic bromides 

 on ammonia. I have given the proof in several communications 

 addressed during the last two years to the Royal Society, and 

 especially in a note || describing some new derivatives of phenylamine 

 and ethylamine published during last summer. The formation of 

 these bodies, their analysis and their transformations, have, I believe, 

 settled the question at issue in a satisfactory manner. 



These researches have been the subject of some remarks on the 

 part of M. Cloez 1J, from which it appears that this chemist has 

 interpreted my silence as a tacit admission of defeat ; he rejects the 

 formulae which I have given for the diatomic derivatives of phenyl- 

 amine and ethylamine, and blames me for having continued my 

 researches on the diatomic bases without having previously replied 

 to his observations. 



Under these circumstances I have been compelled to resume the 

 investigation of the action of dibromide of ethylene upon ammonia, 

 and to reply, after nearly two years have elapsed without M. Cloez's 

 paper having been published, to the series of objections which this 

 chemist has raised against the theory of the diatomic bases. 



* L'Institut, 1853, p. 213. f Proceedings, vol. ix. p. 150. 



J Comptes Rendus, xlvi. p. 255. Proceedings, vol. ix. pp. 277, 287, 651. 



II Proceedings, vol. x. p. 104. ^ L'Institut, 1859, p. 233. 



