in no essential particular from similar substances found
in flesh of all kinds.

Experiments on a somewhat extended scale have shown within recent years
that young and vigorous individuals at least may live and thrive on a
diet composed largely of vegetables; no one has yet shown that a strict
vegetable diet is that best adapted to the average individual, and no
competent authority on this subject at the present time advocates a diet
purely of this kind. It is true that the vegetables ordinarily eaten
contain all of the elements that are essential to the animal system, such
as starch, sugar, fat and albumins. Unfortunately, however, the amount of
the last-named substance is usually so small in food-plants that the
quantity that would have to be eaten by a normal individual taking active
exercise would cost considerably more than if a reasonable proportion of
animal food were included, and--which is of even greater importance--the
digestive powers of the individual who attempted to live only on food of
this character would be severely taxed, and, in the long run, probably
seriously impaired. Furthermore, vegetables and fruits contain
substances, usually in great quantity, that are scarcely acted upon at
all by the digestive juices. Chief among the latter is cellulose, which,
while forming the great bulk of the food of herbivorous animals, is
scarcely suited to the weaker digestive capacity of the human being;
practically none of it is converted to the uses of the body. It is thus
seen that in the average man or woman a dietary consisting largely of
vegetables would result in the presence in the intestines of a greater or
less bulk of indigestible materials, which could subserve no good purpose
other than that they would by their mechanical presence have a tendency
to cause the bowels to act; as is the case with fruits, however, it is
unfortunately true that this large residue of undigested food, in one way
or another, often gives rise to considerable irritation of the mucous
membrane of the intestine, and frequently produces dyspeptic
disturbances, among which looseness of the bowels is common.

This brings us to a consideration of the digestibility of vegetables in
general, which is always the paramount consideration when dealing with
the value of any substance to be used as a food. It has been before
remarked that young and vigorous persons seem to thrive on a dietary
largely of vegetable character, but the case is cer