| " |Indian-meal. |0.26| 8.16|25.6|20.9|352
--+--------+--------------------+-------------------+----+-----+----+----+---
Means |0.66| 6.61|24.9|19.5|333
====================================================+====+=====+====+====+===
Series IV.
--+--------+--------------------+-------------------+----+-----+----+----+---
3 | 10 |Lentil-meal & bran. |Sugar. |3.07| 9.30|19.4|16.9|
3 | " | " |Starch. |3.18| 9.36|19.4|16.9|
3 | " | " |Sugar & starch. |4.06|10.78|17.7|16.1|
| | +-------------------| | | | |
3 | " |Lentils, bran, sugar, starch, ad libitum|4.80| 9.96|18.7|16.5|
--+--------+----------------------------------------+----+-----+----+----|---
Means |3.78| 9.85|18.8|16.6|
----------------------------------------------------+----+-----+----+----+---
Means of all |0.58| 7.34|21.2|17.3|472
====================================================+====+=====+====+====+===

The larger appropriation of the non-nitrogenous constituents of its food
by the pig, as compared with the sheep, must not be attributed solely to
its greater tendency to fatten, but partly to the far more digestible
nature of the food supplied to it.

SECTION V.

RELATION BETWEEN THE QUANTITY OF FOOD CONSUMED BY AN ANIMAL, AND THE
INCREASE IN ITS WEIGHT, OR OF THE AMOUNT OF ITS WORK.

The manifestations of that wondrous and mysterious principle, _life_,
are completely dependent upon the decomposition of organised matter. Not
an effort of the mind, not a motion of the body, can be accomplished
without involving the destruction of a portion of the tissues. In a
general sense we may regard the fat of the animal to be its store of
fuel, and its lean flesh to be the source of its motive power. As the
evolution of heat within the body is proportionate to the quantity of
fat consumed, so also is the amount of force developed in the animal
mechanism in a direct ratio to the proportion of flesh decomposed.
The quantity of fat burned in the body is estimated by the amount of
carbonic acid gas expired from the lungs and perspired through the skin;
the proportion of flesh disorganised is ascertained by the quantity of
urea eliminated in