nd oxides
of nitrogen, which are present in traces, exert a beneficial influence
in oxidizing organic matter. Fresh air and sunlight, acting jointly, are
nature's most effectual disinfectants. Sunshine, fresh air, and pure
water are a health-producing trinity. In discussing the importance of
pure air, water, and sunlight, Ellen H. Richards[97] says:

"The country dweller surrounds his house with evergreens or shade
trees, the city dweller is surrounded with high brick walls.
Blinds, shades, or thick draperies shut out still more, and prevent
the beneficial sunlight from acting its role of germ prevention and
germ destruction. Bright-colored carpets and pale-faced children
are the opposite results which follow. Sunlight, pure air, and pure
water are our common birthright which we often bargain away for
so-called comforts."

And Dr. Woods Hutchinson says of sunlight:

"It is a splendid and matchless servant in the promoting of
healthfulness of the house, for which no substitute has yet been
discovered. It is the foe alike of bacilli and the blues; the best
tonic ever yet invented for the liver and for the scalp, and for
everything between, the only real complexion restorer, and the
deadliest foe of dirt and disease."

[Illustration: FIG. 68.--DIRT AND MANURE EMBEDDED IN SURFACE OF CELERY.]

285. Utensils for Storage of Food.--In order that dishes and household
utensils may be kept in the best sanitary condition, they should be free
from seams, cracks, and crevices where dust and dirt particles can find
lodgment. From the seams of a milk pail that has not been well washed,
decaying milk solids can be removed with the aid of a pin or a
toothpick. This material acts as a "starter" or culture when pure, fresh
milk is placed in the pail, contaminating it and causing it to become
sour. Not only is this true of milk, but also of other foods. Wooden
utensils are not satisfactory for the handling, storage, or preparation
of foods, as it is difficult to keep wood in a sanitary condition.
Uncleanliness of dishes in which foods are placed is too often caused by
the use of foul dishcloths and failure to thoroughly wash and rinse the
dishes. It is always well to rinse dishes with scalding water, as colds
and skin diseases may be communicated from the edges of drinking
glasses, and from forks and spoons, and, unless the dish towels are kept
scrupulously clean, it