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stood that it is an advantage to start the fermentation as soon as 

 ever the grapes are crushed and vatted, as the less the wine is 

 exposed to the air the better are its chances of escaping contamina- 

 tion by the injurious bacteria of diseases which are always lurking 

 in the cellar until a chance is offered to them to invade the wine and 

 taint it. For that reason it is a good practice to start, a few days 

 before vintage proper, a small fermentation under the most favour- 

 able conditions possible. For that purpose some sound and ripe 

 grapes are picked whilst cool, in the morning, crushed, and set 

 fermenting in a clean tub, in which a temperature ranging between 

 75 and 90deg. is carefully maintained. 



This first fermentation will take longer to start than will other- 

 wise be the case, as the appliances for wine-making have not then 

 been leavened, and the spores or germs of the yeast, which during 

 vintage float about in abundance in the atmosphere of the cellar, 

 are still scarce at this early stage of wine-making. 



When the fermentation has well set in, vintage is begun, and as 

 the first vat is being filled a bucketful or two of that ferment is 

 thrown into it, wifch the result that a fermentation of the right sort 

 speedily sets in. 



The subsequent vats are also leavened from those already in 

 full fermentation, and thus the process is continued all through the 

 vintage. This must be done at the right moment, as reference to 

 the paragraphs dealing with the various kinds of ferments show 

 that at the start the apiculate yeasts predominate, and at the end 

 the mycoderma vini, or " flower of wine," and the bacteria of acetic 

 acid and of lactic fermentations, as well as other undesirable micro- 

 organisms which are not uncommon in the wine. During the height 

 of the fermentation, on the other hand, the elliptical yeast, or true 

 wine yeast, has a good hold of the fermenting mass, and is then in a 

 healthy and thriving condition. 



In the course of his researches on beer, Pasteur demonstrated 

 that several kinds of fermentation cannot proceed simultaneously 

 and with an equal intensity in a suitable liquid, and that the most 

 energetic always masters and overpowers the others. The point to 

 bear in mind is, therefore, to surround the particular kind of 

 fermentation one strives to achieve with the conditions most favour- 

 able to its completion. 



INFLUENCE OP TEMPERATURE DURING FERMENTATION. 



Fermentation is the result of combustion. That combustion, 

 as we have seen, is initiated whenever the yeast fungi have access 

 to the sweet juice of the grape. 



According to the researches of scientists, and in the first 

 instance to Berthelot, 180 grammes of grape sugar, in being trans- 



