Notices re'ipeclmg New Books. 63 



them from turning sour, and with the idea that it enabled them 

 to keep for a longer time. As this is a question of some im- 

 portance, both as it regards tlie perfection and the oeconomy of 

 our domestic manufacture, I shall make no apology for entering 

 somewhat largely into it. 



" It had been long thought, irom the vain attempts of che- 

 mists to separate the alcohol which is a constituent part of wine 

 by other chemical processes than distillation, that this substance 

 existed in it, either in a far different condition fi'oin that in which 

 we know it when in its separate state, or that the intoxicating 

 substance contained in wine was not alcohol. This opinion ap- 

 pears to have originated with Rouelle, who imagined that alco- 

 hol was not couipletely formed until the temperature was raised 

 to the point of distillation. More lately the same doctrine was 

 revived and promulgated by Fabbroni in the Memoirs of the 

 Florentine Academy. Mis opinion was founded on the following 

 experiment. When" alcohol is added to new wine, he observed 

 that he could by the introduction of subcarbonate of potash in 

 sufficient quantity separate the added alcohol, while the spirit of 

 the wine remained attached to it as before these additions, and 

 could only be obtained by subjecting it to distillation. Heiice 

 he concluded, that the alcohol v/a.s formed by the action of heat 

 on the elements of wine, or that it was a product of distillation. 



*' But the experiment was not attended with similar results in 

 the bands of other chemists, unless in c:vses where the added al- 

 cohol bore a very considerable proportion to the wine, and it 

 consequently left the question respecting the formation of alcohol 

 in wine in the same state as before. I need not point out the 

 laxity so apparent in Fabbroni's reasonings, as it would lead to 

 discussions too minute for this essay. But the attention of other 

 chemists has been excited towards the same object, and con- 

 clusions the reverse of his have been the conseciuence. If sub- 

 acetate of lead be added to wine, and the clear liquor be then 

 saturated with subcarbonate of potash, the alcohol will be se- 

 parated. It also appears from the experiments of Gay Lussac 

 that alcohol can be separated from wine by distillation at the 

 temperature of GG, and indeed from the trials of Fabbroni him^ 

 self, this separation was produced at 63. More recently by the 

 aid of a vacuum the distillation has been effected at 56, a proof 

 that alcohol is not produced by the action of the heat required 

 for boiling wine or wash on the elements which these substances 

 contain. It must therefore be considered as one of the elemen- 

 tary constituents of wine, and whatsoever phaenomena it may 

 therefore present with reagents or as a subject of chemical in- 

 f{Uiry, mu^t, a8 far as they may tliffer in tlifferent wines, arise 

 from ditlci«iicc« iu it« mode ot combination with one or more of 



the 



