entirely on the skill and carefulness of the maker. An operator should see that the cheese press is straight so that there will be no crocked cheese and that the bandage and press cloths are properly put on, because the finish or appearance of the cheese is an index of his ability. [Illustration: FIG. 49.--Speed knife.] +208. Handling over-ripe and gassy milk.+--Because it is sometimes necessary to make over-ripe[91] or gassy milk[92] into cheese, special directions or precautions are necessary. The best way is to reject this milk. When it is necessary to make it into cheese, the losses are much more than with normal milk. It is a question of making as good a cheese as possible, and the subject of losses is ignored. (1) _Over-ripe milk._--The fact that the milk is over-ripe shows that there is already too much acid present. Every effort must be made to get the curd as firm as possible in the whey with the acid development as low as possible or before the acid has had time to develop any more than can be helped. Although the milk is over-ripe, it is a good plan to add about ¼ of 1 per cent of starter just before the rennet. This starter will not begin to work until the curd is being cheddared and it will help the flavor, especially if any bad fermentation should be present. The rennet is added at 80° F., as this lower temperature tends to check the acid development. More rennet is used, commonly from 4 to 4½ ounces to 1000 pounds of milk. This gives a quicker coagulation. The curd is cut soft, as this tends to expel the moisture more quickly. The heat is turned on sooner after cutting. The time to turn it on and the length of time to heat are determined by the amount of acid. A curd should not be heated in less than fifteen minutes. If the curd has enough acid and has not begun to firm up much, the whey should be drawn down to the surface of the curd, water the temperature of the whey and curd put into the vat, and the curd firmed up in this water. The water washes the acid out of the curd and because of the lack of milk-sugar checks the acid development. If the milk is not so ripe and the curd nearly firm enough, the whey may be drawn off and the curd firmed up by hard stirring in the vat or sink. The curd should not be pushed back enough to be very deep or thick when ready to cheddar. The curd should be cut into very small pieces to cheddar. The smaller the pieces, the faster the whey drains away. Sometimes it is necessary to cut the curd into pieces six inches square. The pieces should not be piled but should be turned often and stood on edge to let the whey drain away and sometimes pressed with the hands to force the whey out. It is often all one man can do to keep the curd turned. [Illustration: FIG. 50.--At the left is a regular shaped, close, solid textured cheese; at the right one puffed up with gas.]