Two influences, one from the custom to allow marriages only within a certain blood bond, and one to allow marriages only outside that family relationship, have worked in the first instance to preserve certain racial traits from extinction, and in the second place to mix the common elements of human nature to the enrichment of the common stock. This balancing regard for the known and allurement of the novel has also worked to give manifold forms of family association, since those customs were superseded. It would seem that not only were "trial marriages" for individuals an ancient, not at all a modern device, to see how the twain could get along together, but varying trial forms of marriage for racial, tribal, and national groups have made all manner of experiments to see what on the whole would serve best the social need in the family relationship. That process of wide experimentation at last settled into the ideal and practice of one father-head, at least, even if still allowing more than one wife and mother within its bond. That father-head seems to have found his place only on condition of grant from society of complete authority over wife and children. =The Patriarchal Family.=--The patriarchal family, which Sir Henry Maine described so well, but which he mistakenly supposed to be the first great type of familial association, placed firmly at the centres of social order the power and responsibility of the man. Doubtless that power and responsibility drew their chief sanction from the idea of man as the real source of being. After man learned that he was as much a parent in being father as woman was a parent in being mother, nothing seemed to have contented him but spiritual supremacy in parenthood. The classic picture and interpretation of this phase of family development is contained in the great drama of the Greeks, the trilogy of Agamemnon, Clytemnestra, Electra, Orestes, and the Erinnyes. Here we see how the mother-side of life, once so powerful as representative of tribal unity, was set aside and overborne by the father-side, as Apollo proudly claims all generative power for man and relegates the mother to the position of an underling nurse. It will be remembered, however, that Athena, although, as Apollo said, "having a father only," makes the mothers still invaluable as guardians of the family altar and as those who can bless or blight both the fruitage of the earth and of the marriage bed. The Greeks, by virtue of their superior self-consciousness when passing through radical social changes, and by virtue also of their power of literary portrayal of experience, have set down for us, for all time, the way by which man attained his unlimited power over woman and over the family order.