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limbs enlarges and strengthens their muscles. Sir Astley Cooper had a patient whose skull was so imperfect as to enable him to examine the movements of the brain.
“I distinctly saw,” Sir Astley says, “ that the pulsation of the brain was regular and slow; but at this time he was agitated by some opposition to his wishes, and directly the blood was sent with increased force to his brain, and the pulsations became frequent and violent.”
A case more interesting still, mentioned by Dr. Caldwell, was a female who had lost a large portion of the skull and dura mater by disease. When she was in a dreamless sleep, her brain was motionless; when her sleep was imperfect, and disturbed by dreams, her brain protruded from the cranium. In vivid dreams, , reported as such by herself, the protrusion was considerable; and when perfectly awake, especially if engaged in active thought, or sprightly conversation, it was much greater.
It is known that the brain of an adult of ordinary intellect is comparatively large, weighing about three and a half pounds, often a little less. In some persons of uncommon mind, it has been known to be much greater. The brain of Byron, for instance, is said to have weighed four and a half pounds, and that of Baron Cuvier four pounds thirteen ounces and a half. On the other hand, the brain of an idiot does not exceed in size that of a child a year old, or between one and two pounds in weight. It has been proved by measurement, that the heads of great thinkers frequently continue to increase until the subjects are fifty years of age, and long after the other portions of the system have ceased to enlarge. This was true of Bonaparte, whose head, though small in youth, in after life became enormous. The reverse is known to occur in cases of protracted insanity; not only the brain diminishes, but the skull itself has often sensibly contracted, as is mentioned of Dean Swift, who, in the latter part of his life, sunk into a state of mental imbecility, a distressing calamity, of which he
appears to have had a presentiment, having predicted “that he would first die at top.”
It is vain then to deny that this wonder
ful part of the body has much to do with the manifestations of mind, though we know of no warrant for the strange conceit of the older physiologists, that there is some central spot in that organ where all the messages of the nerves are ultimately reported, and whence all the orders of the will are issued; or for the figment of Descartes, that the peculiar seat of the mind is the pineal gland. Nor is it incredible, that a different combination of the physical elements of the man may occasion a corresponding difference in the character and qualities of the mind; that a genius for poetry or mathematics, for painting or music, may be connected with a peculiar arrangement or disposition of some particles in the animal economy; in other words, that the earthen vessel is so constructed in some particulars, which escape the eye of the anatomist, as to form a different mould, or give a peculiar shape to the mind, according to the sphere of usefulness for which it is designed by its Creator.' All this may be true, and not conflict with the teachings of revelation. Indeed, for aught we know to the contrary, it is comprehended in what the Psalmist calls the “ fearful and wonderful” construction of man. But in what way the power of thought is originated, or how it is affected by the matter in which it seems to be lodged, is perhaps as profound a secret to Gabriel as it is to us; while the facts by which the truth itself is demonstrated, are, many of them, as affecting as they are familiar. Is the body attacked and prostrated by disease, it is sure of the sympathy of its spiritual partner, which is often reduced to the feebleness of infancy by the debility of the former. Its perceptions become obtuse, the memory fails, the power of attention is gone, as we are often painfully admonished by discovering that the conversation and counsels which were given to the sick, their confessions, and promises, and prayers, are all forgotten on their recovery. Perhaps it is not recollected even, that we were once at their bedside and addressed them. But the connection is not less intimate between the mind and
the nerves, or both, we do not know. Nothing is made more familiar by experience than the fact, that the vigorous action of the former depends, in a great degree, upon the sound condition of the latter. Some assert that the brain, as the common sensorium to which all sensations are ultimately referred, is the first to become sensible to the disorder of the stomach. That, “like two friends in harmonious co-operation, they mutually support each other in health; but, in disease, like sworn enemies, they act and react upon each other with the most destructive malignity.” Who has not observed, without the aid of books or physicians to suggest it, that whatever painfully affects his mind, and disturbs its equanimity, takes away his appetite for food, or the power to digest it, and causes more or less disquietude in the stomach. For this reason, a strong excitement of the mind is often one of the surest remedies for this uneasiness. No man, perhaps, ever had an appetite for food under the full influence of the depressing passions, such as fear or grief. He may eat from persuasion,