rapeutics," p. 800.

Dr. Isaac Ott, an American physiologist of distinction, states in a
description of certain vivisections made by him:

"IT IS A WELL-KNOWN FACT THAT IRRITATION OF A SENSORY NERVE causes an
excitation of the vasomotor centre, WHICH IS INDEXED BY A RISE OF
PRESSURE.... As indirect irritation ALWAYS PRODUCES A RISE OF
PRESSURE, the sensory nerves and the conductors of their impressions
up to the (spinal) cord are not paralyzed."[2]

[2] Ott, "On Physiological Action of Thebain," pp. 11-12.

Dr. Leonard Hill, in an article contributed to Schafer's "Textbook of
Physiology" upon the circulation of the blood, says:

"Arterial pressure is affected reflexly BY STIMULATION OF ANY SENSORY
NERVE IN THE BODY.... The usual result of stimulating a sensory nerve
is A REFLEX RISE OF ARTERIAL PRESSURE."[3]

[3] Schafer's "Textbook of Physiology," vol. ii., pp. 166-167.

The writer goes on to explain that when the tone of the system in
weakened "after prolonged experiment OR DURING THE ADMINISTRATION OF
CHLOROFORM AND CHLORAL," then a fall of pressure may occur.

This phenomenon was known to physiologists many years ago. For
instance, Dr. J. C. Dalton, professor of physiology at the College of
Physicians and Surgeons, in his well-known textbook on physiology,
says that the most frequent instance of reflex constriction of
arteries is that "which follows irritation of the central extremity of
a sensitive nerve."

"This effect has been observed by many experimenters, and is regarded
as nearly invariable. Galvanization of the central extremity of the
sciatic nerve causes general constriction of the bloodvessels
throughout other parts of the body, INDICATED BY INCREASED ARTERIAL
PRESSURE. A similar result is produced by the irritation of ... other
sensitive nerves, or nerve roots."[1]

[1] Dalton's "Physiology," pp. 507-508.

And, referring to another experimenter, Dr. Crile, puts the case
clearly:

"PAIN INCREASES (BLOOD)-PRESSURE. In four cases of trauma (injury), a
rise of 20 to 40 was noted upon pressure upon a nerve. Even in a
healthy person, pinching the integument was noted increase the
pressure."[2]

[2] Crile "On Blood-Pressure," p. 341.

It would seem unnecessary to accumulate evidence regarding a
physiological phenomenon so long and so firmly established. We may
therefore take it for granted that in a living animal or in a human
being, as a general rule, the irritation of a sensory nerve w