of retaining sugar and controlling its output is one of the utmost
significance for growth and metabolism, the resistance to infections,
the response to emergency situations, and in general to the
mobilization of energy for physical and mental purposes. For without
sugar sufficiently at hand for the cells, no muscle work or nerve
work, the essentials of the struggle for existence, are possible.

The pancreas is an organ with both an internal and external secretion.
The external secretion, long known, evolved by the major portion of
the gland, is poured into the small intestine to play the star in
digestion. Scattered here and there among the definitely glandular
cell groups creating the external secretion are smaller collections of
cells, called the islets of Langerhans, which have been demonstrated
to elaborate the internal secretion. There are about a million of
these islands in each gland. The hormone has been called insuline.
Unlike most of the glands with a double secretion in which the
internal is absolutely independent, and so to speak, unconscious of
the external, these two of the pancreas are often disturbed together,
perhaps because trouble easily hits them both together.

Quite the most well-known disease due to disturbed internal secretory
function of the pancreas is diabetes. An enormous amount of work has
been spent upon the various aspects of it as a mystery. Hundreds of
papers in a dozen languages upon the subject are in existence. In a
nutshell, they have established pretty well that diabetes is a disease
in which there is an excess of sugar in the blood and urine because of
an insufficient amount of the secretion of the islands of Langerhans
in the pancreas. Removal of the pancreas makes the body, essentially
the liver, unable to retain sugar, as well as unable to burn up sugar
for energy. The situation is comparable to a locomotive with its coal
bins leaking, and the coal itself acting as if made of slate or some
equally uncombustible or only partially combustible material.

The control of sugar mobilization from the liver, where it is stored
as glycogen or animal starch, is divided between the pancreas and
the adrenals, the pancreas acting as the brake, the adrenals as the
accelerator of the mechanism. Adrenal and pancreas are therefore
direct antagonists, the pans of the scale which represents sugar
equilibrium in the organism. Diabetes may be regarded as a disturbance
of the adrenal-pancreas bal