ese 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.

The most common example of the direct transmission of disease from
animals to men is through the development of the parasite in a pig,
known as "trichinosis." This disease is due to a minute worm scarcely
visible to the naked eye which lives in the muscles of men, dogs, swine,
and other animals, and also under other conditions in their intestines.
Millions of the young trichinae may live in the flesh of a pig without
producing any particular difference in the appearance of the flesh.
After four or five weeks, they become incased in small white spherical
capsules which later, after a year or so, become entirely calcified. In
this form they live for years in the flesh of the pig and do no harm in
that condition. If, however, this flesh be eaten by man without being
cooked so thoroughly as to destroy the little worm (about one
twenty-fifth of an inch long) which has been living in these capsules,
then they become distributed around the stomach of the person eating
that flesh, enter the intestines, and attach themselves to the membranes
there. They grow very rapidly, and broods of from 500 to 1000 young
worms are produced from each one of the entering worms, and, since there
may be a quarter of a million or more in an ounce of pork, it is not
surprising that the total number deposited in the intestines from a
single meal of raw pork is enough to produce great distress,
characterized by vomiting and diarrhea. Fortunately, the disease is not