d been exposed to diphtheria or were in
hospitals where they were in danger of becoming exposed to it, with the
delightful result that only a very small per cent of those so protected
developed the disease, and of these not a single one died! This
protective vaccination, however, cannot be used on a large scale, as in
the case of smallpox, for the reason that the period of protection is a
comparatively short one, probably not exceeding two or three weeks.

Suppose that, in spite of all our precautions, the disease has gained a
foothold in the throat, what will be its course? This will depend, first
of all, upon whether the invading germs have lodged in their commonest
point of attack, the tonsils, palate, and upper throat, or have
penetrated down the air-passages into the larynx or voice-organ. In the
former, which is far the commoner case, their presence will cause an
irritation of the surface cells which brings out the leucocyte cavalry
of the body to the defense, together with squads of the serum or watery
fluid of the blood containing fibrin. These, together with the
surface-cells, are rapidly coagulated and killed by the deadly toxin;
and their remains form a coating upon the surface, which at first is
scarcely perceptible, a thin, grayish film, but which in the course of
twenty-four to forty-eight hours rapidly thickens to the well-known and
dreaded false membrane. Before, however, it has thickened in more than
occasional spots or patches, the toxin has begun to penetrate into the
blood, and the little patient will complain of headache, feverishness,
and backache, often--indeed, usually--before any very marked soreness in
the throat is complained of. Roughly speaking, attacks of sore throat,
which begin first of all with well-marked soreness and pain in the
throat, followed later by headache, backache, and fever, are not very
likely to be diphtheria. The bacilli multiply and increase in their
deadly mat on the surface of the throat, larger and larger amounts of
the poison are poured into the blood, the temperature goes up, the
headache increases, the child often begins to vomit, and becomes
seriously ill. The glands of the neck, in their efforts to arrest and
neutralize the poison, become swollen and sore to the touch, the breath
becomes foul from the breaking down of the membrane in the throat, the
pulse becomes rapid and weak from the effect of the poison upon the
heart, and the dreaded picture of the disease rap