it is very harmful to drink iced water or iced tea, or to eat ice-cream
at meals. These things are injurious to us at any time, but they do the
greatest amount of harm when taken with the food.

~9. Things sometimes Eaten which are not Foods.~--Things which are not
foods are often used as foods, such as mustard, pepper, and the various
kinds of seasonings. Soda, saleratus, and baking-powders also belong to
this class. All of these substances are more or less harmful,
particularly mustard, pepper, and hot sauces.

~10. Common Salt.~--The only apparent exception to the general rule that
all condiments and other substances which are not foods are harmful is
in the case of common salt. This is very commonly used among civilized
nations, although there are many barbarous tribes that never taste it.
It is quite certain that much more salt is used than is needed. When
much salt is added to the food, the action of the digestive fluids is
greatly hindered. Salt meats, and other foods which have much salt added
to them, are hard to digest because the salt hardens the fibres of the
meat, so that they are not easily dissolved by the digestive fluids.

~11. Care of the Teeth.~--The teeth are the first organs employed in the
work of digestion. It is of great importance that they should be kept in
health. Many persons neglect their teeth, and treat them so badly that
they begin to decay at a very early age.

~12.~ The mouth and teeth should be carefully cleansed immediately on
rising in the morning, and after each meal. All particles of food should
be removed from between the teeth by carefully rubbing both the inner
and the outer surfaces of the teeth with a soft brush, and rinsing very
thoroughly with water. A little soap may be used in cleansing the teeth,