Probably the only thing which can be done is to instruct the public, and make known, so far as possible, the influences of hereditary tendencies, publishing them in the higher text-books of schools, and in periodicals. It might be more clearly understood in reference to marriage, that a sentimental fancy or a choice founded on the existence of like characteristics, either mental or physical, not only often proves to be of little real value in after-life toward securing happiness, but on the other hand proves, too often, to be the source of vast misery to parents, their children, and the community in which they may live; that the highest consideration for the present and future should lead to careful examination as to inherited characteristics on both sides, and of a selection which may tend toward elimination, rather than an increase, of these. It might be more fully understood that, generally, characteristics of body and mind of _different qualities_, within certain degrees of limit, contribute toward securing a well-balanced and healthy system, and also toward a larger degree of happiness in domestic relations; that acquired diatheses, as well as those inherited, are transmitted to those who come after; that violations of the laws of healthy brain activity are almost sure to be punished in the persons of children, whether they have consisted in immoderate devotion to business or study, or in any of the physical indulgences. In this way some advance may be hoped for, in guiding toward that course in which lies the least danger. The old adage, however, that "the fathers have eaten sour grapes, and the children's teeth are set on edge," was a truth well understood some thousands of years ago,--and yet the fathers go on indulging in sour grapes, because the great truth fails to have taught its lesson, and the heedlessness of youth requires line upon line, and precept upon precept, as well as, ofttimes, the sternest of discipline. The future will doubtless be, in a large degree, as in the past, but we may hope that when the laws of inheritance are more commonly known, when the learning of them becomes a part of the general education of the young, their influence will be more beneficent than at the present time. Especially may we have reason to expect that such will prove to be the result in reference to those diatheses which are formed through the influence of alcohol and tobacco, or by the indulgence of the lower passions, but the elimination of insanity by these means can, at the most, be only partial. The second measure by means of which the unfavorable influences of heredity may be modified in their subjects, is that of _education_.