There are two common methods of making these cheeses which are in vogue in the United States, namely, the “stirred curd” or “granular” method and, second, the Cheddar method. (Bulletin 104, Department of Agriculture of Pennsylvania, 1902.) The latter one is the more extensively used. The second product does not differ essentially in character from the first, though the latter method, it is claimed, gives a more solid cheese and one of more uniform character and with a slightly less content of moisture. Since the Cheddar method has practically come into sole use, displacing the first method, a description of the Cheddar method alone will be sufficient to illustrate the method of making large cheeses which are now so common on the American market and which have such a well merited reputation. The process is divided into eight parts: First, coagulating the milk; second, cutting the curd; third, heating the curd; fourth, removing the whey; fifth, cheddaring the curd; sixth, milling the curd; seventh, salting and pressing the curd; eighth, curing the cheese. _Rennet._--As has been said in the description of cheese making, the material which is most useful in the precipitation of the curd is rennet. The rennet is the secretion of the stomach of various animals, that of the calf being most highly priced for cheese making. The fourth stomach of the animal is the one which is used in the manufacture of rennet. The aqueous extract made from these stomachs contains a ferment which has the property of coagulating casein in a very high degree. One part of good rennet preparation from healthy stomachs of calves will coagulate 1000 parts of milk. In former days rennet was freshly made and used at the factories. At the present time it is largely prepared on a commercial scale and sold to the cheese maker. It is highly important that the rennet used in cheese making should be of the best quality, as an inferior grade gives a bad taste and color to the cheese. Just as in the manufacture of fermented beverages and making of bread the character of the yeast is a dominant factor in the nature of the finished product, so it is even to a greater degree in the case of rennet. Those who purchase the rennet already made should therefore be certain it is of a quality to give the desired character to the cheese. The greater the amount of milk fat in milk the larger the proportion of rennet, since the milk fat protects to some extent the casein from the action of the ferment. Experience has shown also that during the summer the rennet acts more readily upon the milk, probably due to the higher temperature. Care should be taken to avoid the use of any excess of rennet, since anything more than the amount necessary to conduct the coagulation is apt to add an unpleasant flavor to the cheese. The curd also in such cases is less cohesive and makes a tougher and drier product which does not lend itself so readily to the ripening process.