LECTURE VIII.] 



HISTORY OF CHEMISTRY. 



137 



confirms his view by preparing the bromine and iodine com- 

 pounds of this radical, which he also assumes to be present in 

 aldehyde and in acetic acid. He writes : 



C 4 H 6 - 

 C 4 H 6 ,C1 2 

 C 4 H 6 ,Br 2 - 

 C 4 H 6 ,C1 2 + H 2 Cl2 ~ 



C 4 H 6 ,Br 2 + H 2 Br 2 - 



(Ethylene 

 Hydrocarbon (Ethylene 



Hypothetical radical Aldehydene 



Chloraldehydene 



Bromaldehydene 



Chloride of Hydrocarbon 



chloride) 

 Bromide of 



bromide) 



C 4 H 6 ,O +H 2 O - Aldehyde 

 C 4 H (J O 3 +H 2 O - Acetic acid 



This investigation of Regnault's, carried out in 1835, was 

 prompted by Liebig, and was intended to prove to Dumas that 

 the radical etherin is not present even in ethylene chloride ; it 

 was intended to overthrow the etherin theory, and it may have 

 had much influence in moving Dumas to give up his former 

 views. It is true that in consequence of this investigation 

 Liebig also abandoned the radical ethyl, and tried to explain 

 the ethereal compounds on the assumption of a radical acetyl, 

 C 4 H 6 . 2r These substances are again compared with the salts 

 of ammonia, but in the latter the radical amide is now 

 assumed. 



27 Annalen. 30, 139. 



