hough temporary rise of the blood pressure, that a real enthusiasm
for its investigation was generated. As the upshot, a number of other
significant properties besides the first of blood-pressure raising,
have been put down to its credit. Chemical tests demonstrated that
it originated in the medulla. The exact amount of it present in the
medulla, in the blood issuing from the adrenals and in the circulation
in general have been determined. The concentration in the blood is
about one part in twenty million, while there is about a hundred
thousand times as much stored in the gland as reserve. In infections
and intoxications, after muscular exertion, and with profound
emotions, there is a decrease of it in the gland and an increase in
the blood. Pain and excitement, especially fear and rage, will bring
about its discharge from the gland. With its entry into the blood,
there is a tremendous heightening of the tone, a _tensing_, of the
nervous system. The nerve cells become more sensitive to stimuli,
more sugar is poured into the blood from the liver, more red blood
corpuscles are squeezed into the circulation from the blood lakes of
the liver and spleen. There is a redistribution of the whole blood
mass, a good deal of it being withdrawn from the internal viscera, and
hurried to the skeleton muscles and the brain. The heart beats more
strongly, the eye sees more clearly, the ear hears more distinctly,
and the breathing is more rapid. The temperature rises, the hair of
the head and the body becomes erect, the skin gets moist and greasy.
It will help a fatigued muscle to regain its normal tone. In short, it
has a reinforcing action upon the nutritive properties of the blood,
the tone of the muscles, and the activity of the brain and the
vegetative nerves.

Chemists set themselves the task of discovering just what was the
substance possessed of such extraordinary and hitherto unimagined
properties. The pure adrenalin was isolated, capable of evoking all
the reactions of the impure adrenal extract mixtures. The final
triumph was the preparation of it artificially in the laboratory,
its synthesis. When a substance can be synthesized in the chemist's
laboratory, it means that its composition has become thoroughly
understood. Here at last was an example of those mysterious internal
secretions, the existence of which had indeed been postulated and
proven, but which had never actually been inspected by the eye of
mortal man. To hav