some opposition to his wishes, and directly the blood
was sent with increased force to the brain, and the pulsation became
frequent and violent." Sir Astley hence concludes that, in the treatment
of injuries of the brain, if you omit to keep the mind free from
agitation, your other means will be unavailing.

A still more remarkable case is said to have occurred in the hospital of
Montpellier in 1821. The subject of it was a female who had lost a large
portion of her scalp, skull-bone, and dura mater. A corresponding
portion of her brain was consequently bare, and subject to inspection.
When she was in a dreamless sleep, her brain was motionless, and lay
within the cranium; but when her sleep was imperfect, and she was
agitated by dreams, her brain moved and protruded without the cranium.
In vivid dreams the protrusion was considerable; and when she was awake
and engaged in active thought or sprightly conversation, it was still
greater.

In alluding to this subject, Dr. Caldwell remarks, that if it were
possible, without doing an injury to other parts, to augment the
constant afflux of healthy arterial blood to the brain, the mental
operations would be invigorated by it. This position is illustrated by
reference to the fact that when a public speaker is flushed and heated
in debate, his mind works more freely and powerfully than at any other
time. And why? Because his brain is in better tune. What has thus
suddenly improved its condition? An increased current of blood into it,
produced by the excitement of its own increased action. That the blood
does, on such occasions, flow more copiously into the brain, no one can
doubt who is at all acquainted with the cerebral sensations which the
orator himself experiences at the time, or who witnesses the unusual
fullness and flush of his countenance, and the dewiness, flashing, and
protrusion of his eye.

Indeed, in many instances, the increased circulation in the brain
attendant on high mental excitement reveals itself by its effects when
least expected, and leaves traces after death which are but too legible.
Many are the instances in which public men have been suddenly arrested
in their career by the inordinate action of the brain induced by
incessant toil, and more numerous still are those whose mental power has
been forever impaired by similar excess.

It is generally known that the eye, when tasked beyond its strength,
becomes insensible to light, and ceases to convey