When the liquor is about 70°, it is generally tunned off into a large vat or cask for it to ferment. About three quarters of a pint of yeast is mixed with a little of the wort, and as soon as it begins to work it is added to the rest. Another mode is, as soon as the wort has cooled to 70°, to convey it in the coolers to a cellar, where the temperature is about 55°, and then to mix two gallons of it with a pint of good thick yeast, and put it into an upright eighteen-gallon cask, the head of which has been knocked out, but which is covered with a piece of flannel, on which the head is laid loosely. As soon as the fermentation has begun, about three gallons more of the wort are added, provided it has not cooled below 65°; but, if it has, a pailful must be taken out and heated, so that when mixed with the rest of the three gallons, the whole shall be about 70°. When this has been added to the wort fermenting in the cask and well stirred, the cask should be covered and left to work for the night. Early the following morning the working wort should be tried with a thermometer, and, if it is between 70° and 75°, five gallons more of the wort should be added, heated as before to about 68°. The liquor should then be stirred, and left for six hours, after which three gallons more wort at 65° are added. It is then covered and left for four hours more, after which nearly all the remaining wort is added, reserving only about two quarts. This process is very tedious, but it is said to make the ale exceedingly fine and clear; and, if the proportions be one bushel and a half of malt to a pound and three quarters of hops to make twelve gallons, it is said exactly to resemble the celebrated Indian ale. If the heat of the working wort be ever found above 75°, the remaining wort should be added cool, and the whole should be tunned out as soon as possible. In the usual mode of brewing, when the fermentation has gone on till the yeast begins to look brown, the beer should be tunned; that is, the yeast is removed, and the beer is put into the casks in which it is to remain; and, in general, the beer is not taken down into the cellar till at this period. The casks are placed slantingly, with the bung out; and they are always kept quite full, being filled up with beer reserved for that purpose, as the beer they contain works out. In about a fortnight all the fermentation will be over, and the casks may be bunged up.