FEBMENT OILS. 361 



A paper on the composition of Grcqje spirit and Wine Brandy, 

 by Ch. Ordonneau, ^Yas read at the meeting of the French Academy 

 of Sciences, 25th Jan., 1886,* being presented by Pasteur. The 

 author of that paper remarks that the production of Grape spirit 

 having diminshed, in consequence of the ravages of the phylloxera, 

 more attention has been paid to the production of pure grain 

 spirit, and that recent improvements in distillatory apparatus 

 have resulted in the production of a nearly pure '•' alcool neutre " 

 (silent spirit) ; but yet, such alcohol still possesses a peculiar 

 odour, recognisable by professional tasters, and known by the 

 name of " odeur de trois-six," and which is absent in the alcohol 

 of wine. In his memoir, Ordonneau says : — " I searched for the 

 cause of this difference, and made a comparative study of Old 

 Cognac brandy and ordinary commercial spirit. I submitted to 

 fractional distillation in an apparatus very similar to the 

 Henninger-Claudon, 3 hectolitres of Cognac brandy, 25 years old 

 and of undoubted purity. The most volatile portions contained 

 aldehyde, acetic ether, acetal, and traces of propionic and butyric 

 ethers. The least volatile portion, after being rectihed several 

 times, yielded about 1,200 grams, of a product possessing the 

 particular odour of the brandy under investigation. As a result of 

 the fractionations I was able to identify the presence of the bodies 

 contained in this Cognac, as per table annexed : — 



Acetic aldehyde 3 grams, per hectolitre 



Acetic ether 35 „ „ 



Acetal 35 „ „ 



Propylic alcohol, normal 40 „ „ 



Butylic alcohol, normal 218-60 „ „ 



Amylic alcohol 83'80 



Hexylic alcohol 0-60 



Heptylic alcohol 1-50 „ „ 



Propionic, Butyric & Caproic ethers 3 „ „ 



Q^^nanthic ether, about 4 „ „ 



Bases, amines 4 „ „ 



The important feature in this analysis is the determination of 

 so large an amount as 218*60 grams, per hectolitre of normal 

 butylic alcohol, boiling at 116^-118^ C. It is also notable that 

 the pure amyl alcohol, the regular presence of which in wines has 



* Comptes Rendus, cii., p. 217. 



