FERMENTATION OF WINE. 167 



continues to improve, more spirit being formed, and 

 consequently more tartar thrown down. Wine also 

 becomes stronger when kept in the wood, because, 

 under these circumstances, a greater proportion of 

 water passes oiF by evaporation, than of alcohol. 

 This is always found to be the case when a mixture 

 of spirit and water is kept in a slightly porous vessel, 

 the water evaporates faster than the spirit. 



391. Finally, the wine is either racked off into a 

 clean cask, the lees being left behind, or it is clarified, 

 or fined, with albumen or isinglass, and then bottled. 

 Wines which are intended to be sparkling or efi'er- 

 vescing are bottled before the fermentation is quite 

 finished, so that the carbonic acid subsequently 

 evolved, remains stored up in the liquid. 



392. In making what are termed home or domestic 

 wines, the juice of various fruits, &c., is mixed with 

 sugar and fermented. A good deal of skill is required 

 in this operation, and care must be taken so to pro- 

 portion the difi^erent ingredients, as to insure a proper 

 fermentation. It is a very common error to use too 

 much sugar, and not add enough ferment to cause its 

 due fermentation ; for this purpose the yeast or fer- 

 ment of wine is best ; that obtained from the ferment- 

 ation of beer injures the flavor of the wine. 



393. When the vinous fermentation of must is quite 

 complete, it should not be suffered to remain longer 

 in contact with the lees, because when this is the case, 

 especially with weak wines, many circumstances may 

 tend to commence the acetous fermentation, giving 



