of progeria, first recorded
by the Briton, Hastings Guilford. A queer spectacle in which a child
incontinently grows old without having lived--in the course of a few
weeks or months. You look upon him and see senility on a small scale,
but with all its peculiarities: wrinkled skin, apathy, gray hair and
all the rest of it. All we can say about it is that it is probably due
to a paralysis of all the glands of internal secretion, a removal
of their influence upon the cells. Contrariwise to the feeding of
thyroid, removal of the thyroid of tadpoles will prevent their
development into frogs. If iodine is then fed to them, say mixed with
flour, normal metamorphosis will occur. If Body is the tool chest
which we carry about with us, as Samuel Butler said, then to the
thyroid belongs the name of tool-maker.

Another function of thyroid that must be taken into consideration is
what has been spoken of as its antitoxic function--in plainer English,
its power to prevent poisoning, or to increase resistance against
poisons, including the bacteria and other living agents which
cause the infectious diseases. Each molecule of food, ingested for
assimilation into our substance, accumulates a history of wanderings
and pilgrimages, attachments and transformations beside which the
gross trampings of a Marco Polo become the rambling steps of a
seven-league booted giant. In the course of its peregrinations, it
becomes a potential poison, potential because it is never allowed to
grow in concentration to the danger point. The thyroid plays its role
of protector like all the internal secretory machines. In an animal
deprived of a thyroid the feeding of meat shortens life--a single
sample of how it works to guard against intoxication from within. The
feeding of thyroid will also raise the ability of the cells to stand
poisons introduced from without--intoxications of all sorts. Alcohol
and morphine will affect in much smaller doses the subthyroid person
than the normal or the hyperthyroid. As regards the infections, which
directly or indirectly kill most of us, the injection of thyroid will
increase the content in the blood of the protective antibodies which
preserve us, temporarily at any rate, against malignant invaders. The
opsonins, for example, those substances which butter the bacteria so
that the appetite of the white cells for them is properly roused, are
mobilized by thyroid feeding or injection. Other substances in the
blood which de