Jump to content

Page:Popular Science Monthly Volume 54.djvu/267

From Wikisource
This page has been proofread, but needs to be validated.
BRAIN WEIGHTS AND INTELLECTUAL CAPACITY.
253

squat figure. . . . The convolutions were broad and simple, but not shallow. The gray matter was as broad as usual."[1]

The writer has examined many brains of persons morally or intellectually below the average—such as murderers, negroes, and others sunk in ignorance. He has invariably found the layer of vesicular or gray matter to be thicker than that of Daniel Webster's brain. Elephants, porpoises, whales, dolphins, and the grampus all have this layer thicker than the most intellectual men. Another great objection to locating mind in the gray matter of the brain is that this substance is found in the interior part of the spinal cord, and in all the nerve centers throughout the body; so that, if mind is situated in it, it is not confined to the brain, but dwells in the spine also, and is distributed all through the human frame. Still another objection lies in the fact that wherever the gray matter exists near the surface of the brain, it consists of three distinct layers, separated by a white substance, and the outermost layer is white, not gray.[2]

The septum lucidum consists of gray matter. The corpus striatum, situated at the base of the lateral ventricles, nearly in the center of the brain, was from three eighths to half an inch in diameter in an ox which was dissected in Edinburgh. This is about the same amount as is found in the corpus striatum of the human brain. There would be lively times if it were possible for a mental faculty to occupy at once all the localities where gray matter is found!

None of the suppositions about certain qualities of mind inhering in particular portions of the brain have been proved, nor have they stood the tests of science.

The theories which have assumed that the cultivation of the intellect gives shape and size to the brain within and consequently to the skull without, advocates of which have not been wanting, have been disproved by the collected facts. "There is no proof," says Dr. J. O. Nott, in his Types of Mankind, "of the theory that the cultivation of the mind or of one set of faculties can give expansion or increased size of brain. The Teutonic races, in their barbarous state, two thousand years ago, possessed brains as large as now, and so with other races."

The St. Louis Globe Democrat of November 13, 1885, gives an account of some excavations on the Mount Ararat farm, east of Carrollton, Illinois, where the bones of thirty-two Indians or mound builders were unearthed. "They were not a diminutive race, as some people have supposed, some of the thigh bones being sixteen inches long, and some of the skulls twenty-four inches in circumfer-


  1. Idiocy and Imbecility, London, 1877, pp. 216-219.
  2. See The Brain as an Organ of Mind, London, 1880, p. 465; also, The Human Brain, London, 1847, pp. 288, 289.