cial force to food of a starchy
nature,--bread, potatoes, oatmeal, rice, etc. In order to digest food of
this character it must be very thoroughly cooked and when finally placed
upon the table it should be of such consistence that it requires chewing
before it can be swallowed. Not only is this necessary from the
standpoint of breaking up the larger particles into smaller ones, thus
permitting the food to pass freely through the stomach and intestine, but
it is of the greatest importance for it to be thoroughly soaked with the
saliva during the process. It is thus of no advantage for starches to be
served in a finely divided form--in fact it is directly the contrary,
since under such circumstances it is almost always the case that such
foods are swallowed without having been insalivated.

What has been said concerning the mastication of starches applies with
almost equal force to other foods. Without exception their digestibility
is much increased by thorough chewing. As the result of recent
experiments carried out by means of the X-ray, it has been shown that
particles of food of any considerable size will not pass from the stomach
into the intestine; as often as an object of this kind attempts to force
its way from the former into the latter the opening between the two
closes, and as a consequence the food is retained in the stomach longer
than it is in health--resulting in the course of time in catarrhal
conditions of the organ just named, and an unnatural relaxation of its
muscular walls. Under such circumstances the patient quickly develops
symptoms of indigestion, and if his habits be not corrected the trouble
gradually grows worse until the sufferer becomes a chronic dyspeptic.

_Classes of Nutritive Substances._--All substances that are of any
appreciable value in nutrition may be divided into those that are
nitrogenous in character (albumins, legumins), the carbohydrates
(starches and sugars) and compound ethers (fats). Of all these the
nitrogenous foods are the most important, since they contain the material
from which the great bulk of the body is largely composed, and at the
same time there is every evidence that in case of need they may be broken
up into chemical substances that may take the place of any of the other
kinds of foods; upon nitrogenous food, then, a man may live alone, while
this cannot be done on other articles of diet. The fats, starches and
sugars are very closely related to each other, and