attain the size and age
of two or three years and there stop altogether, as if a permanent
brake were applied to the wheels of their growth. Some higher types
may even come to speak connected sentences, and exhibit a certain
mild spontaneity, though stupid and slow and abnormally deliberate,
resembling the acquired form of thyroid deprivation or insufficiency,
for which Ord invented the name myxedema.

I have filled in with some detail this thumbnail sketch of thyroid
deprivation as it occurs in infancy to illustrate how wide a sweep the
gland's lariat embraces. Skin, hair, bones, muscle and fat, brain and
intelligence, growth and development, are modified precisely as the
size and shape of certain crystals are modified by the presence or
absence of ingredients in an apparently homogeneous solution. A
fertilized ovum, in which the predecessor of the thyroid gland is
present, that is to say, in which there is the seed and soil for its
sprouting, looks the same as one without that formative material. Yet,
when the time comes for the internal secretion of the thyroid to put
in its oar in the metabolic game, its presence or absence makes all
the difference in the world to the individual.

In the middle of the nineteenth century, when the concentration of
phosphorus in the brain was established as significant, the cry for
the emphasis of that fact was--without phosphorus no thought is
possible. We can much more relevantly declare that without thyroid,
no thought, no growth, no distinctive humanity or even animality is
possible. For the epigram about phosphorus was bombast, since it can
be declaimed with equal truth that without oxygen, without carbon,
without nitrogen, without any of the food elements that go to make
up the chemical composition of brain matter, no thought is possible.
Indeed, if one were set upon the indictment of a single chemical
element as the begetter of consciousness, the prisoner at the bar
would have to be copper. There is more copper in the brain by a
considerable degree than in any other organ of the body. Which perhaps
will be exceedingly regretted by the patrons of the aristocracy of the
soul who would have it as an emanation of a deposit in the brain of
silver at least, if not gold. They are like the old lady who would
never permit herself to be cured of her ailments except by gold plated
pills. Copper, however, is not necessary to intelligence. Without
thyroid there can be no complexity of tho