Flinders Petrie, discussing those great migrations due to the unrestricted expansion of barbarous races which have devastated Europe from the dawn of history, remarks: "We deal lightly and coldly with the abstract facts, but they represent the most terrible tragedies of all humanity--the wreck of the whole system of civilisation, protracted starvation, wholesale massacre. Can it be avoided? That is the question, before all others, to the statesman who looks beyond the present time."[16] Since Petrie wrote, only ten years ago, we have had occasion to realise that the vast expansions which he described are not confined to the remote past, but are at work and producing the same awful results, even at the very present hour. The great and only legitimate apology which has been put forward for the aggressive attitude of Germany in the present war has been that it was the inevitable expansive outcome of the abnormally high birth-rate of Germany in recent times; as Dr. Dernburg, not long ago, put it: "The expansion of the German nation has been so extraordinary during the last twenty-five years that the conditions existing before the war had become insupportable." In other words, there was no outlet but a devastating war. So we are called upon to repeat, with fresh emphasis, Petrie's question: _Can it be avoided_? All humanity, all civilisation, call upon us to take up our stand on this vital question of birth control. In so doing we shall each of us be contributing, however humbly, to "one far-off divine event, To which the whole creation moves." [1] J.M. Coulter, _The Evolution of Sex in Plants_, 1915; Geoffrey Smith, "The Biology of Sex," _Eugenics Review_, April, 1914. [2] See, _e.g._, Geddes and Thomson, _The Evolution of Sex_, Ch. XX.; and T.H. Morgan, _Heredity and Sex_, Ch. I. [3] To quote one of the most careful investigators of this point, Northcote Thomas, among the Edo-speaking people of Nigeria, found that the average number of living children per husband was 2.7; including all children, alive and dead, the average number was per husband 4.5, and per wife 2.7. "Infant mortality is heavy" (Northcote Thomas, _Anthropological Report of Edo-speaking People of Nigeria_, 1910, Part I., pp. 15, 63). [4] The same end has been rather more mercifully achieved in earlier periods by infanticide (see Westermarck, _Origin and Development of the Moral Ideas_, Vol. I., Ch. 17). It must not be supposed that infanticide was opposed to tenderness to children. Thus the Australian Dieyerie, who practised infanticide, were kind to children, and a mother found beating her child was herself beaten by her husband. [5] See Havelock Ellis, _The Nationalisation of Health_.