Page:Popular Science Monthly Volume 29.djvu/659

Rh different civilized nations of the world, there is an average of one insane in live hundred inhabitants. The undoubted steady increase of the insane under care and observation would seem to be greater than can be fairly accounted for by the greater attention now given to their welfare"(Maudsley). These two instances, recognized as the most important in the hereditary class, will serve as examples; it is not desired here to show in what proportion of cases disease is transmitted from generation to generation; the writer hopes to be able at a later date to give some general laws respecting hereditary affections.

The heredity of genius has been fully proved by that very interesting writer and accurate observer, Francis Galton, and he has put forward in a masterly way the claims of eugenics, or race-culture. This must be effected, he urges, by a rational system of natural selection. "Men," says the same author, "have long been exempted from the full rigor of natural selection, and have become more mongrel in their breed than any other animal on the face of the earth." The laws of natural selection, considered broadly, prevail among men more than at first sight appears.

Among the lower animals, as Mr. Darwin has shown, strength, beauty, voice, and such qualities, determine a choice: the rustic maiden often chooses her husband because he is stronger physically than his rivals; the more intellectual woman would naturally look for mental superiority, and so on. Now, the strongest point in any rational natural selection must be first and foremost pure blood; and by that is not meant blood that has come down through a long line of ancestors merely, but blood which is free from any hereditary taint. We are all familiar with the member of some "old family," a slight, flat breasted, precociously intelligent child, whose slender, graceful neck, bright eyes shaded by long lashes, thin, white skin through which the blue veins show, declare to the educated eye the presence of tubercular disease. We know that, if such a child matures, the odds are overwhelming that its offspring will continue to disseminate the disease. Or take any number of insane persons, with whose family history you are more or less familiar, and the certainty with which you will be able to trace the disease to hereditary predisposition is wonderful. We know of no government sufficiently strong to forbid the banns of a man whose lungs are full of tubercle, or of a woman upon whose person cancer has shown itself. The only way to begin to stamp out hereditary disease is to direct the tide of public opinion toward it. We would not if we could enforce the Spartan rule, but we can and should exert a power they knew not of, the press, and educate our people to the full importance of this subject. Even our proverbial mauvaise honte can not object to showing the young of both sexes the horrors of a legacy of an hereditary disease. Those who are to become the fathers and mothers of our next generation should be warned before they make a step into the dark, and should