[1] Pasteur, in his Studies on Beer, says that the reason has not yet been discovered, but that he has no doubt that it may be attributed, principally, to the fact that the interstices between the grapes, and the spaces which the bunch leaves throughout, considerably increase the volume of air placed at the service of the germs of ferment.
[2] Ferment cells, however, occur in considerable numbers in the neighborhood of places where alcoholic fermentation is carried on, and the germs, perhaps, may be found in the atmosphere near a vineyard, and in those cases the ferments and their germs may be borne about to some extent by the wind.
[3] Machard says about 125 grammes to a tonneau, or 4 or 5 ounces to 250 gallons of wine.
[4] It must be remembered that he is writing for the cold climate of the Jura, where the grapes do not naturally acquire that degree of maturity necessary for sweet wines.
[5] Fermenting house.
[6] A pipe is 138 wine gallons, or 115 Imperial.
[7] Tuns.
[8] It will be noticed that Dr. Bleasdale says that the treading is repeated during active fermentation. Probably different practices prevail in different localities.
[9] About 4¾ to 9½ per cent—say 5 to 10.
[10] 4.35 per cent.