CELLARING. 105 



of the operation of that cause which afterwards de- 

 stroys them, and which is neither more nor less than 

 the chemical alteration in their constituents, properties 

 which render them more agreeable both to smell and 

 taste. 



As it is very seldom possible to analyse wine after 

 it has attained a great age, the few analyses we possess 

 of this nature are of extreme value. Some Malaga 

 wine which was buried during the conflagration of 

 London, A.D. 1666, and only dug up 40 years since, 

 though nearly 200 years old, was found perfectly 

 good and well flavoured.* 



"We have traced the chemical history of wine 

 from its first beginning to the time when, having been 

 clarified in casks, and poured into wooden vessels and 

 bottles, it is fit for use ; and we must now endeavour to 

 make ourselves acquainted with the operation of that 

 slow process to which I have already alluded, and with 

 the circumstances which may expose wine to its 

 influence. 



As a general rule, wines which have retained a con- 

 siderable portion of albuminous matter, and possess 

 but little tannic acid, cannot resist the influence of 

 time. They become acid, or undergo some other 

 change. This occurs in the case of Ehine wines, 

 which contain but little alcohol ; and all those wines 

 which contain much sugar, or but little tannic acid, 

 cannot be kept long. 



* Journ. of Science, vol. i. p. 136. 



