Page:Popular Science Monthly Volume 29.djvu/401

Rh acquirement from the moment of birth, while others are not called into play for many months afterward.

I have known many a child to be crowded prematurely to a point in mental development that has either arrested further growth of the intellectual faculties or caused its death indirectly.

Hardly a month passes in which I am not compelled to urge parents (often against their inclinations) to modify or discontinue some defective system of mental training of their children. Many cases of idiocy, epilepsy, St. Vitus's dance, dropsy of the brain, and other nervous diseases of childhood encountered by physicians, might have been prevented if the parents had been made intelligent respecting the dangers that encompassed the child, and used proper precautions against them.

Within the past decade, the functions of different parts of the brain have been determined with an approach to scientific precision. We are now able to trace (by methods lately discovered) the course and terminations of separate nerve-bundles which compose the bulk of the brain. Pathology has helped us to verify, in the case of man, the deductions drawn from experiments upon the brains of animals. The microscope has enabled us, furthermore, to detect structural differences between various groups of brain-cells, whose functions have been shown to be totally distinct from each other.

These and other discoveries (too numerous to mention here) have a practical value as well as a scientific one. They afford us many hints which may be applied during life. They aid us materially also in preventing as well as relieving diseased conditions of the wonderfully constructed mechanism.

These are the few physiological facts which I am particularly desirous of impressing upon the reader, since they form a basis for my conclusions. These may be summarized as follows:

1. Different areas of the surface of the brain have functions peculiarly and exclusively their own. Thus the brain's surface may be likened to a map with its various territories, each of which is at times perfectly independent of the other in respect to its functions, but still capable of concerted action with the rest when such action is required. We recognize as distinctly defined those areas, for example, which preside over motions, sight, smell, taste, touch, hearing, general sensibility, and some others.

2. Each of these areas of the brain-surface has to be separately educated. The memories connected with past experiences are stored within the cells of the area which appreciates the facts as they occur.

3. Some parts of the brain develop more rapidly than others.

4. The education of some parts of the organ consists chiefly of the