14 ON THE ART OF MAKING WINE. 



those used in our domestic manufacture, artificially 

 compounded. It is thus only that we can hope 

 to establish such general rules, as may be appli- 

 cable to those ever-varying cases, where particular 

 rules of practice would be unattainable. A gener- 

 al notion has already been given of the substances, 

 to whose mixture the process of fermentation is 

 owing, and the essential ones will be found to con- 

 sist of sugar, vegetable extract, tartarous and malic 

 acid, and water. These are indispensable, and to 

 their varieties in proportion, some of the most re- 

 markable differences in the results of fermentation 

 will be found owing. Among these, sugar is the 

 most essential, since the alcohol of wine is more 

 particularly derived from the decomposition of 

 this substance. The strength of the wine is pro- 

 portioned to the quantity of sugar fermented, and 

 the most saccharine juices, therefore, afford the 

 strongest wine, or in the artificial process, if so it 

 may be termed, that compound to which the great- 

 est proportion of sugar has been added, will be 

 capable of giving the strongest, if duly managed. 

 But we have already seen, that sugar and water 

 alone do not ferment, if the sugar be pure, and 

 that this process only takes place in clayed sugars, 

 or in those which contain a portion of that vegeta- 

 ble extract which characterizes the sweet princi- 

 ple. In the juices of fruits, the sugar and extract 

 exist in a state of combination, to which, as I be- 

 fore remarked, the term of Sweet Principle ha,$ 



