360 ADULTERATION OF WINE. 



determination of the solid substances remaining after 

 evaporation, of the ashes of the wine, and the use of 

 such reagents as indicate chlorine, sulphuric acid, 

 lime, &c. &c. All this must be effected in order to 

 compare the quality of the wine to be analysed with 

 a pure example of the same sort. 



It will always remain doubtful whether alcohol or 

 water have been added, as long as the limits of the 

 normal composition of wine of the same quality have 

 not been passed. 



The determination of the colour, smell, and flavour, 

 must be combined with the foregoing, but these sub- 

 jective impressions cannot furnish any proof. 



Among the less objectionable adulterations we 

 must consider the employment of means to lessen the 

 too great acidity of young wine ; as pulverised chalk 

 or marble, gypsum, clay, or other substances, for the 

 purpose of clearing, not discolouring, the wine ; also, 

 the addition of a little tannic acid to preserve wine 

 which threatens to become ropy ; the addition of albu- 

 men, isinglass, gluten and tannic acid, cream or milk, 

 either to clear wine or to make it darker. I call many 

 of these adulterations, though they are not generally 

 so considered. 



A comparative examination would sometimes en- 

 lighten us upon these matters. Isinglass, albumen, 

 tannic acid, whether added immediately or later, and 

 cream, are so completely precipitated that they may 

 be sought for in vain afterwards. 



