ctically all
separated into its sodium and chlorine particles, or ions. It has
recently been shown that the sodium ions are necessary for the
contraction of the muscles, including the muscles of the heart.
There is also reason for believing that the different ions may enter
into temporary combination with food particles, and in this way
assist in the processes of nutrition.

53 Chittenden, _The Nutrition of Man_.

54 Compiled from different sources, but mainly from Atwater's _Foods:
Nutritive Value and Cost_, published by the U.S. Department of
Agriculture.

55 The calorie is the adopted heat unit. As used in this table it may
be defined as the quantity of heat required to raise 1 kilogram (2.2
pounds) of water, 1 degree centigrade. The calories also show the
relative amount of energy supplied by the different foods.

56 While alcohol cannot be classed as a food, it is believed by some
authorities to contain _food value_ and, in the hands of the
physician, to be a substance capable of rendering an actual service
in the treatment of certain diseases. It might, for example, be used
where one's power of digestion is greatly impaired, since alcohol
requires no digestion. But upon this point there is a decided
difference of opinion. Certain it is that no one should attempt to
use alcohol as food or medicine except under the advice and
direction of his physician.

57 A layer of connective tissue between the mucous membrane and the
muscular coat is usually referred to as the _submucous_ coat. This
contains numerous blood vessels and nerves and binds the muscular
coat to the mucous membrane.

58 The saliva may continue to act for a considerable time after the
food enters the stomach. "Careful examination of the contents of the
fundus (large end of the stomach) by Cannon and Day has shown that
no inconsiderable amount of salivary digestion occurs in the
stomach."--FISCHER, _The Physiology of Alimentation_.

59 Perhaps the simplest method of inducing vomiting is that of
thrusting a finger down the throat. To make this method effective
the finger should be held in the throat until the vomiting begins.
An emetic, such as a glass of lukewarm salt water containing a
teaspoonful of mustard, should also be taken, and, in the case o