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242 80°. I mean when the process is carried to the desired extent, and I think Liebig admits these heats to be free from any of that danger which he dreads from higher temperatures.

The time occupied in the fermentation need not exceed from forty to sixty, or at most eighty, hours, varying according to the strength and quality of the beer. The beer is thus much less liable to be injured by atmospheric electrical fluctuations than by longer processes, which often prove detrimental to it.

During the fermentation, when well conducted, there should be such an accumulation and constant discharge of carbonic acid gas, as to preclude any communication with the atmosphere, at least under common circumstances. When the fermentation has been carried to the desired extent, the beer (I do not now speak of the process called skimming) is discharged from the fermenting-tun into smaller vessels or casks, for the purpose of throwing off the yeast. During this time, also, the vessel is frequently filled up, in order to assist the discharge of the yeast; neither can it in this stage of the process have any connection with the atmosphere, unless from electrical interference, which as yet we have no means of entirely avoiding. This operation may again occupy about two or three days, according to circumstances, to allow the beer to get steady and cool. It is then stowed away in