resting, are the effects which
are produced upon the nervous system. One day, while the child is
recovering, and is possibly beginning to sit up in bed, a glass of milk
is handed to him. The little one drinks it eagerly and attempts to
swallow, but suddenly it chokes, half strangles, and back comes the
milk, pouring out through the nostrils. Paralysis of the soft palate has
occurred from poisoning of the nerves controlling it, caused by direct
penetration of the toxin. Sometimes the muscles of the eye become
paralyzed and the little one squints, or can no longer see to read.

Fortunately, most of these alarming results go only to a certain degree,
and then gradually fade away and disappear; but this may take months or
even longer. In a certain number, however, the nerves of respiration, or
those controlling the heart-beat, become affected, and the patient dies
suddenly from heart failure.

This strange after-effect upon the nervous system, which was first
clearly noticed in diphtheria and syphilis, has now been found to occur
in lesser degree in a large number of our infectious diseases, so that
many of our most serious paralyses and other diseases of the nervous
system are now traceable to such causes.

These effects of the diphtheria toxin are also of interest for a
somewhat unexpected reason, since it has been claimed that they are
effects of the antitoxin, by those who are opposed to its use. Every one
of them was well recognized as a possible result of diphtheria long
before the antitoxin was discovered, and every one of them can be
readily produced by injections of diphtheria bacilli or their toxin into
animals.

It is quite possibly true that there are more cases of nerve-poisoning
(neuritis) and of paralysis following diphtheria than there were before
the use of antitoxin, but that is for the simple and sufficient reason
that there are more children left alive to display them! And between a
child with a temporary squint and a dead child few mothers would
hesitate long in their choice.

CHAPTER XI

THE HERODS OF OUR DAY: SCARLET FEVER, MEASLES, AND WHOOPING-COUGH

Why is a disease a disease of childhood? First and fundamentally,
because that is the earliest period at which a human being can have it.
But the problem goes deeper than this. There is no more interesting and
important group of diseases in the whole realm of pathology than those
which we calmly dub "the diseases of childhood," and there