WINE. 



75 



perience has shown that a wine, the fermentation 

 of which is very slow, is never good, and, therefore, 

 when the weather is too cold, the fermentation is 

 accelerated by heating the place in which the wine 

 is made. A too hasty and violent fermentation is 

 also hurtful, from the dissipation and loss of some 

 of the spirit. However, we may distinguish, in the 

 ordinary method of making wines of grapes, two 

 periods in the fermentation, the first of which lasts 

 during the appearance of the sensible effects above 

 alluded to, in which the greatest number of ferment- 

 able particles ferment. After this first effort of fer- 

 mentation, these effects sensibly diminish, and ought 

 to be stopped for reasons hereafter to be mentioned. 

 The fermentative motion of the liquor then ceases. 

 The heterogeneous parts, that were suspended in 

 the wines by this motion, and render it muddy, are 

 separated, and form a sediment called lees, after 

 which the wine becomes clear. But though the 

 operation is then considered as finished, and the 

 fermentation apparently ceases, it does not really 

 cease ; and it ought to be continued in some degree 

 if we would have good wine. In this new wine, a 

 part of the liquor probably remains that has not 

 fermented, and which afterwards ferments, but so 

 very slowly, that none of the sensible effects produced 

 in the first fermentation are here perceived. The 

 fermentation, therefore, still continues in the wine, 

 during a longer or shorter time, although in an im- 

 perceptible manner ; and this is the second period 

 of the spirituous fermentation, which may be called 

 the imperceptible fermentation. The effects of 

 this fermentation are the gradual increase of the 

 quantity of alcohol, and of the separation of the 

 acid salt, called tartar, from the wine. As the 

 taste of tartar is harsh and disagreeable, it is evi- 

 dent that the wine, which, by means of the insen- 

 sible fermentation, has acquired more alcohol, and 

 has disengaged itself of the greater part of its tar- 

 tar, ought to be much better and more agreeable ; 

 nd for this reason chiefly old wines are universally 

 Detter than new. But insensible fermentation can 

 only ripen and meliorate the wine if the sensible 

 fermentation have regularly proceeded, and been 

 stopped in due time. We know certainly that, if 

 a sufficient time have not been allowed for the first 

 period of the fermentation, the unfermented matter 

 that remains, being in too large a quantity, will 

 then ferment in the bottles, or close vessels, in 

 which the wine is put, and will occasion effects 

 so much more sensible as the first fermentation 

 shall have been sooner interrupted ; hence these 

 wines are always turbid, emit bubbles, and some- 

 times break the containing vessels, from the large 

 quantities of air disengaged during the fermenta- 

 tion. We have an instance of these effects in the 

 wine of Champagne, and in others of the same 

 kind : the sensible fermentation of which is inter- 

 rupted, or rather suppressed, that they may have 

 this sparkling quality. It is well known that these 

 wines make the corks fly out of the bottles ; that 

 they sparkle and froth when they are poured into 

 glasses ; and lastly, that they have a taste much 

 more lively and piquant than wines that do not 

 sparkle ; but this sparkling quality, and all the 

 effects depending on it, are only caused by a consi- 

 derable quantity of carbonic acid gas, which is dis- 

 engaged during the confined fermentation that the 

 wine has undergone in close vessels. This air, 

 not having an opportunity of escaping, and of be- 

 ing dissipated as fast as it is disengaged, and being 

 interposed betwixt all the parts of the wine, com- 



bines, in some measure, with them, and adheres in 

 the same manner as it does to certain mineral 

 waters, in which it produces nearly the same effects. 

 When this air is entirely disengaged from these 

 wines, they no longer sparkle, but lose their brisk 

 taste, and become insipid. Such are the qualities 

 which wine acquires, in time, when its first fer- 

 mentation has not continued sufficiently long. 

 These qualities are given purposely to certain 

 wines to indulge taste or caprice ; but they are 

 not regarded as suited to daily use. Wines for 

 daily use ought to have undergone so completely 

 the sensible fermentation, that the succeeding fer- 

 mentation shall be insensible, or, at least, very near- 

 ly so. Wine, in which the first fermentation has 

 been too far advanced, is liable to worse inconve- 

 niences than that in which the first fermentation 

 has been too quickly suppressed ; for every ferment- 

 able liquor is, from its nature, in a continual in- 

 testine motion, more or less strong, according to 

 circumstances, from the first instant of the spiri- 

 tuous fermentation, till it is completely purified ; 

 hence from the time of the completion of the spi- 

 rituous fermentation, or even before, the wine be- 

 gins to undergo the acid or acetous fermentation. 

 This acid fermentation is very slow and insensible, 

 when the wine is included in very close vessels and 

 in a cool place ; but it gradually advances, so that 

 in a certain time the wine becomes completely sour. 

 This evil cannot he remedied, because the fermen- 

 tation may advance, but cannot be reverted. Wine 

 merchants, therefore, when their wines become 

 sour, can only conceal or remove this acidity by 

 alkalies or alkaline earths. But these additions 

 communicate to wine a dark, greenish colour, and 

 a taste which, though not acid, is somewhat dis- 

 agreeable. Besides, calcareous earths accelerate, 

 considerably, the total destruction and putrefaction 

 of the wine. Oxides of lead, having the property 

 of forming with the acid of vinegar, a salt of an 

 agreeable saccharine taste, which does not alter the 

 colour of the wine, and which, besides, has the ad- 

 vantage of stopping fermentation and putrefaction, 

 might be employed to remedy the acidity of wine, 

 if lead and all its preparations were not pernicious 

 to health, as they occasion most terrible colics, and 

 even death, when taken internally. If wine con- 

 tain oxide of lead, it may be discovered by trans- 

 mitting through a portion of it, in a wine-glass, a 

 current of sulphureted hydrogen gas, which will 

 cause a glistening, black precipitate of sulphuret 

 of lead. See Fermentation, and P'inegar. 



When the wine has attained a sufficient degree 

 of maturity, it is freed from the lees, by being 

 racked, as it is termed, into a clean cask ; and, in 

 order to prevent a renewal of the fermentation, it 

 is subjected to the operation of sulphuring. This 

 process is generally performed by means of sulphur 

 matches, applied to the cask into which the wine 

 is to be racked, and should the fermentation still 

 continue, must be renewed as often as is necessary. 

 Sometimes must, strongly impregnated with sul- 

 phurous acid gas, is added to the wine, and answers 

 the same purpose. After sulphuring, the greater 

 proportion of wines require to be further clarified, 

 or fined, before they attain a due brightness. For 

 this purpose, various substances are used, which, 

 by their chemical or mechanical action, unite with 

 such materials as disturb the purity of the wine, 

 and precipitate with them to the bottom. The 

 substances in general use are isinglass and the 

 white of eggs ; but, as these are of a putrescent 



