The regulations referred to say in substance that when the lesions occur in a single part of the body, as in the neck, liver, lungs, or in certain specified combinations, the meat may be used; but that where the lesions affect more than one or two parts of the body, the carcass must be rendered at a temperature of not less than 220 degrees Fahrenheit for four hours into lard or tallow. This really means that an animal only slightly affected with tuberculosis, where the lesions are slight and are confined to the tissues of certain organs only, may be used for food. This has been decided only after very careful reading of all known facts, and is particularly important in view of the opposition to the use of milk of tuberculous cows. The tuberculin test, on which depends the determination of tuberculosis in cows, is so delicate that a very slight lesion is sufficient to cause a reaction. The lesions are so slight as in many cases to be entirely overlooked by the ordinary butcher. The United States regulations allow such a carcass to be butchered and used for food after the cow has been condemned by the tuberculin test as a milk-producing animal. This does not mean, of course, that those parts of the body affected by the tuberculosis lesions shall be used, but, since these lesions are usually segregated, they can readily be cut out without reference to the rest of the body. The other point to be noted in selecting or rejecting animals for slaughter is their general condition. This means that they should be of the proper weight,--that is, not emaciated, but with a proper amount of fat,--that the flesh should be firm and elastic and the skin supple. Nor should they be either too young or too old. A prominent example of the first error is in the sale of calves under three weeks old, known as "bob-veal," and while some sanitarians will not object to eating calves under three weeks old, the consensus of opinion is that to be fit for food a calf should be at least that age. Fortunately, it is for the interest of the butcher to hold the calf until it has arrived at a certain weight, and the stringent laws of most states prohibiting the sale of bob-veal make it dangerous and expensive for the farmer to slaughter young calves unless they are of the right age.