y unrecognized.
That is the child's mouth. Here the germs find lodgment, here they find
a culture medium--at the gateway of the human system. The mouth is
never out of service and is almost never in a state of true
cleanliness. Solid particles from the breath, saliva, food between the
teeth, and other debris form a deposit on the teeth and decompose in a
constant temperature of ninety-eight degrees Fahrenheit. In the normal
mouth from eight to twenty years of age the teeth present from twenty
to thirty square inches of dentate surface, constantly exposed to
ever-changing, often inimical, conditions. This bacterially infected
surface makes a fairly large garden plot. Every cavity adds to the
germ-nourishing soil. Dental caries--tooth decay--is a disease hitherto
almost universal from birth to death. Thus the air taken in through the
mouth becomes a purveyor of its poisonous emanations and affects the
lung tissues and the blood. Food and water carry hostile germs down
into the stomach. Thence they may be carried into any organ or tissue,
just as nourishment or poison is carried.

Moreover, the child with an unclean mouth not only infects and
reinfects himself but scatters germs in the air whenever he sneezes or
coughs. In a cold apartment where there is no appreciable current of
air a person can scatter germs for a distance of more than twenty-two
feet. Germs are also scattered through the air by means of salivary or
mucous droplets. It is this fact that makes colds so dangerous.

TABLE VIII

=City of Manchester Education Committee=

=INFECTIOUS OR CONTAGIOUS DISEASES IN SCHOOLS INFORMATION FOR TEACHERS=

Four columns are omitted: (1) Interval between Exposure to
Infection and the First Signs of the Disease; (2) Day from Onset
of Illness on which Rash appears; (3) Period of Exclusion from
School after Exposure to Infection; (4) Period of Exclusion from
School of Person suffering from the Disease

-----------+------------------------------+------------+------------------
DISEASE | PRINCIPAL SIGNS AND SYMPTOMS | Method of | REMARKS
| | Infection |
-----------+------------------------------+------------+------------------
Measles |_Begins like cold in the | |After effects
|head_, with _feverishness, | |often severe.
|running nose, inflamed and | |Period of greatest
|watery eyes, and