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vegetables it is obtained by certain chemical processes. The sac- 

 charine fermentation appears to be the agent by which fruits ac- 

 quire an encrease of their sweetness, after being plucked from the 

 parent stock, when no action of vegetable life can go on. By an 

 acceleration of this process, by the aid of caloric, in the operation 

 of baking, this effect is still more manifestly produced. 



If to vegetabje substances possessing this principle, an addition 

 of water be made, and a slight increase of caloric be made, an in- 

 testine motion soon takes place, called, from its product, the vinous 

 fermentation. During this process, the object of which appears to 

 be, the diminishing the dose of carbon, which is united with the 

 oxygen and hydrogen in the sugar, we find carbonic acid gas is 

 rapidly separated, a feculent sediment is deposited, and a new 

 substance, called yeast or must, is formed, which rises to the surface, 

 and which, if added to any vegetable infusion containing the sac- 

 charine principle, will immediately excite that peculiar intestine 

 motion on which this species of fermentation depends. 



When this separation has taken place, but whilst the fermenta- 

 tive motion is still discoverable, if the fluid be carefully preserved 

 from the access of the air, it passes on, through an almost, and, in 

 the latter stages of it, an entirely, imperceptible fermentation, during 

 which it obtains its highest degree of strength, becoming a clear 

 and bright spiritous intoxicating liquor. 



But if, instead of this seclusion, the process be allowed to go on 

 in contact with the atmospheric air, instead of a spiritous liquor, 

 a peculiar vegetable acid, or vinegar, is the result ; which will also 

 require, for its preservation, a seclusion from the atmospheric air, 

 since otherwise it will suffer a further decomposition, its volatile 

 principles escaping, and its earth and carbon only remaining. 



Thus also will almost any mass of dead vegetable matter, exposed 

 to the air of the atmosphere, soon pass on to a putrid fermentation, 



