previously recognized. With the loss
of the function of these glands by disease, the body was deprived of
something formed by them which was essential to its proper working.
Then, in the last third of the century, came in rapid succession the
demonstration of the relations of the pancreas to diabetes, of the vital
importance of the thyroid gland and of the pituitary body. Perhaps no
more striking illustration of the value of experimental medicine has
ever been given than that afforded by the studies upon those glands.

The thyroid body, situated in the neck and the enlargement of which is
called goitre, secretes substances which pass into the blood, and
which are necessary for the growth of the body in childhood, for the
development of the mind and for the nutrition of the tissues of the
skin. If, following an infectious disease, a child has wasting of this
gland, or if, living in a certain district, it has a large goitre,
normal development does not take place, and the child does not grow in
mind or body and becomes what is called a cretin. More than this--if in
adult life the gland is completely removed, or if it wastes, a somewhat
similar condition is produced, and the patient in time loses his mental
powers and becomes fat and flabby--myxedematous. It has been shown
experimentally in various ways that the necessary elements of the
secretion can be furnished by feeding with the gland or its extracts,
and that the cretinoid or myxedematous conditions could thus be cured or
prevented.

Experimental work has also demonstrated the functions of the suprarenal
glands and explained the symptoms of Addison's disease, and chemists
have even succeeded in making synthetically the active principle
adrenalin.

There is perhaps no more fascinating story in the history of science
than that of the discovery of these so-called ductless glands. Part
of its special interest is due to the fact that clinicians, surgeons,
experimental physiologists, pathologists and chemists have all combined
in splendid teamwork to win the victory. No such miracles have ever
before been wrought by physicians as those which we see in connection
with the internal secretion of the thyroid gland. The myth of bringing
the dead back to life has been associated with the names of many great
healers since the incident of Empedocles and Pantheia, but nowadays the
dead in mind and the deformed in body may be restored by the touch
of the magic wand of science. Th