LECTURE XII.] HISTORY OF CHEMISTRY. 247 



in the same relation to the latter as the anhydride of sulphuric 

 acid does to the acid : 



C 4 H 4 0, S 2 4 A 



Ethylene oxide. Sulphuric anhydride. 



Glycol. Sulphuric acid. 



By heating ethylene oxide with glycol, Wurtz next prepared 

 the polyethylene alcohols 7G which Louren^o had obtained, a 

 short time previously, from ethylene bromide and glycol. 77 The 

 importance of these substances was enhanced by the acids 

 obtained from them by oxidation ; 78 they furnished excellent 

 examples of the formation of substances according to the con- 

 densed types such as Wurtz afterwards so well understood how 

 to employ in explaining the silicates. 79 Finally, by the action 

 of ammonia and its analogues, Wurtz obtained from ethylene 

 oxide bases containing oxygen. 80 These substances afterwards 

 became of greater interest in consequence of the synthesis of 

 neurine from glycol-chlorhydrine and trimethylamine. 81 



The adoption of ethylene as a diatomic radical furnished 

 Hofmann 8L> with a means of correctly regarding the bases pre- 

 pared by Cloez in i853. 83 These now appeared as substances 

 derivable from two molecules of ammonia, and bearing the 

 same relation to glycol that ethylamine does to alcohol. By the 

 further study of these substances, 84 Hofmann succeeded in 

 adducing new proofs of the accuracy of the theory of poly- 

 atomic radicals, and in preparing the way to a clear conception 

 of the complicated metal-ammonium compounds. 



It would be unjust if I were to close these observations 

 without alluding to H. L. Buff's claim with respect to the recog- 



76 Comptes Rendus. 49, 813. 77 Ibid. 49, 619. 78 Ann. Chim. [3] 

 69, 317. 79 Repert. de Chimie pure. 2, 449 ; compare also Lecons de 

 philosophic chimique, Paris, 1864, 181. 80 Comptes Rendus. 49, 898 ; 

 53, 338. 81 Ibid. 65, 1015. 82 Ibid. 46, 255. 83 L'Institut. 1853, 

 213 ; Jahresbericht 1853, 468. 84 Proc. Roy. Soc. 10, 224 and 594 ; 

 Comptes Rendus. 49, 781 ; 51, 234 ; Proc. Roy. Soc. II, 278 ; Comptes 

 Rendus. 53, 18, etc. 



