f blood and nervous power; and in the
comparative lassitude that follows a hearty meal, every adult has proof
that this supply of blood and nervous power is at the expense of the
system at large. If the requisite nutriment is obtained from a great
quantity of innutritious food, more work is entailed on the viscera than
when it is obtained from a moderate quantity of nutritious food. This
extra work is so much loss--a loss which in children shows itself either
in diminished energy, or in smaller growth, or in both. The inference
is, then, that they should have a diet which combines, as much as
possible, nutritiveness and digestibility.

It is doubtless true that boys and girls may be reared upon an
exclusively, or almost exclusively, vegetable diet. Among the upper
classes are to be found children to whom comparatively little meat is
given; and who, nevertheless, grow and appear in good health. Animal
food is scarcely tasted by the offspring of labouring people; and yet
they reach a healthy maturity. But these seemingly adverse facts have by
no means the weight commonly supposed. In the first place, it does not
follow that those who in early years flourish on bread and potatoes,
will eventually reach a fine development; and a comparison between the
agricultural labourers and the gentry, in England, or between the middle
and lower classes in France is by no means in favour of vegetable
feeders. In the second place, the question is not simply a question of
_bulk_, but also a question of _quality_. A soft, flabby flesh makes as
good a show as a firm one; but though to the careless eye, a child of
full, flaccid tissue may appear the equal of one whose fibres are well
toned, a trial of strength will prove the difference. Obesity in adults
is often a sign of feebleness. Men lose weight in training. Hence the
appearance of these low-fed children is far from conclusive. In the
third place, besides _size_, we have to consider _energy_. Between
children of the meat-eating classes and those of the
bread-and-potato-eating classes, there is a marked contrast in this
respect. Both in mental and physical vivacity the peasant-boy is greatly
inferior to the son of a gentleman.

If we compare different kinds of animals, or different races of men, or
the same animals or men when differently fed, we find still more
distinct proof that _the degree of energy essentially depends on the
nutritiveness of the food_.

In a cow, subsisting on so