In Ayrshire, and in some other countries, it is customary to cut the dried stomach into small pieces, and to put it, with a handful or two of salt and one or two quarts of water, into a jar, to allow it to stand for two or three days, afterwards to pour upon it another pint for a couple of days, to mix the two decoctions, and when strained, to bottle the whole for future use. In this state it may be kept for many months. In making rennet, some use pure water only, others prefer clear whey, others a decoction of leaves, such as those of the sweetbrier, the dog-rose, and the bramble, or of aromatic herbs and flowers; while others again, put in lemons, cloves, mace, or brandy. These various practices are adopted for the purpose of making the rennet keep better, of lessening its unpleasant smell, of preventing any unpleasant taste it might give to the curd, or finally of directly improving the flavor of the cheese. The acidity of the lemon will, no doubt, increase also the coagulating power of any rennet to which it may be added. The rennet thus prepared is poured into the milk previously raised to the temperature of 90° or 95° F., and is intimately mixed with it. The quantity which it is necessary to add varies with the quality of the rennet, from a tablespoonful to half a pint for 30 or 40 gallons of milk. The time necessary for the complete fixing of the curd varies also from 15 minutes to an hour or even an hour and a half. The chief causes of this variation, are the temperature of the milk, and the quality and quantity of the rennet employed. Different Qualities of Cheese. The temperature of new or entire milk, when the rennet is added, should be raised to about 95° F.; that of skimmed milk need not be quite so high. If the milk be warmer the curd is hard and tough, if colder, it is soft and difficult to obtain free from the whey. When the former happens to be the case, a portion of the first whey that separates may be taken out into another vessel, allowed to cool, and then poured in again. If it prove to have been too cold, hot milk or water may be added to it; or a vessel containing hot water may be put into it before the curdling commences; or the first portion of whey that separates may be heated and poured again upon the curd. The quality of the cheese, however, will always be more or less affected, when it happens to be necessary to adopt any of these remedies. To make the best cheese, the true temperature should always be attained as nearly as possible, before the rennet is added. Mode in which the Milk is warmed.