It is still a question whether science has fully discovered those laws of hereditary health, the disregard of which causes so many marriages disastrous to generations yet unborn. But much valuable light has been thrown on this most mysterious and most important subject during the last few years. That light--and I thank God for it--is widening and deepening rapidly. And I doubt not that, in a generation or two more, enough will be known to be thrown into the shape of practical and proveable rules; and that, if not a public opinion, yet at least, what is more useful far, a wide-spread private opinion, will grow up, especially among educated women, which will prevent many a tragedy and save many a life. But, as to the laws of personal health: enough, and more than enough, is known already, to be applied safely and easily by any adults, however unlearned, to the preservation not only of their own health, but of that of their children. The value of healthy habitations, of personal cleanliness, of pure air and pure water, of various kinds of food, according as each tends to make bone, fat, or muscle, provided only--provided only--that the food be unadulterated; the value of various kinds of clothing, and physical exercise, of a free and equal development of the brain-power, without undue overstrain in any one direction; in one word, the method of producing, as far as possible, the mentem sanam in corpore sano, and the wonderful and blessed effects of such obedience to those laws of nature, which are nothing but the good will of God expressed in facts--their wonderful and blessed tendency, I say, to eliminate the germs of hereditary disease, and to actually regenerate the human system--all this is known; known as fully and clearly as any human knowledge need be known; it is written in dozens of popular books and pamphlets. And why should this divine voice, which cries to man, tending to sink into effeminate barbarism through his own hasty and partial civilisation,--"It is not too late. For your bodies, as for your spirits, there is an upward, as well as a downward path. You, or if not you, at least the children whom you have brought into the world, for whom you toil, for whom you hoard, for whom you pray, for whom you would give your lives,--they still may be healthy, strong, it may be beautiful, and have all the intellectual and social, as well as the physical advantages, which health, strength, and beauty give."--Ah, why is this divine voice now, as of old, Wisdom crying in the streets, and no man regarding her? I appeal to women, who are initiated, as we men can never be, into the stern mysteries of pain, and sorrow, and self-sacrifice;--they who bring forth children, weep over children, slave for children, and, if they have none of their own, then slave, with the holy instinct of the sexless bee, for the children of others--Let them say, shall this thing be?