270 (ENANTHIN GUM. 



with the copper test, and another which does not 

 give this reaction till it has been resolved into sugar 

 by the action of an acid. To this question I reply in 

 the negative. The gum of which we spoke (p. 248) 

 was obtained by evaporating wine with chalk, that is, 

 by saturating the free acids ; whilst the O3nanthin 

 described by Faure is obtained from the evapora- 

 tion of wines alone, and therefore it is exposed 

 to the influence of free acids and heat. The gum 

 mentioned (p. 248), when treated with sulphuric acid 

 and heat, is resolved in a few minutes into sugar. 

 Solution of gum arabic, when exposed for a short time 

 to heat, and acted upon by tartaric acid, passed into 

 dextrin, and afterwards into grape sugar; so also 

 the gum of wine, which has been evaporated with 

 tartaric acid, will be found resolved into dextrin. 



There is therefore no ground for assuming that two 

 kinds of gum are present in wine. The gum of wine 

 when prepared, according to Faure' s method, has the 

 reaction of dextrin, but when separated by chalk, that 

 is, in the unaltered form in which it actually appears 

 in wine, it shows no reaction of dextrin, and cannot 

 be justly called by that name. 



"With respect to the amount of gum w r hich, ac- 

 cording to Faure, is greater in old cellared wines 

 than in young ones, this fact, even if proved (which 

 it is not, since he worked with a very impure sub- 

 stance), would be either the consequence of a 

 gradual resolution of the sugar of wine into gum, 



