But in the case of the expectant mother there is more warrant for offering an opinion even in the absence hitherto of definite evidence. Apart from any opinion as to the propriety of smoking by women in general, there is a definite issue in the case of the expectant mother. A very young child is now being exposed to the poisons of tobacco smoke, and if we are right in passing laws to prevent this poisoning in the case of the urchin of eight years (who is really, of course, eight years and nine months old), what shall we say regarding the unborn child who is only eight months old? I have observed that the expectant mother may have her liking for tobacco replaced by violent dislike during pregnancy. =The poison of syphilis.=--Brief mention must here be made of syphilis as a racial poison. Sooner or later the eugenic campaign must and will face this question, about which a murderous silence is now maintained. No other disease can rival syphilis in its hideous influence upon parenthood and the future. But it is no crime for a man to marry, infect his innocent bride and their children: no crime against the laws of our little lawgivers, but a heinous outrage against Nature's decrees. When, at last, our laws are based on Nature's laws, criminal marriages of this kind may be put an end to. The lay reader should acquaint himself with the play of Brieux, _Les Avariés_. The student may be referred to Forel's _Sexual Question_, Dr. C. F. Marshall's _Syphilology and Venereal Diseases_, and his article, “Alcohol and Syphilis” in the _British Journal of Inebriety_, January, 1908. * * * * * This chapter and the last do not profess to do more than indicate the field of eugenics which the term racial poisons suggests. Our business in the present volume is, if possible, to see eugenics whole: to treat of this new science adequately is not for one author or one generation. It is earnestly to be hoped that the medical profession will speedily take up this question of the racial poisons. Already the profession is beginning to become the great instrument of _individual hygiene_: and every year will enhance the importance of this work, as compared with the cure of disease. Now negative eugenics is substantially _racial hygiene_: and the next great epoch in the evolution of medicine and the medical profession will be the enrolment of its knowledge and influence in the cause of racial hygiene. May this book do a little to hasten that day. The two next chapters are designed to introduce that aspect of our subject which may be called National Eugenics, and especially with reference to decadence. Here is a matter which appeals to minds of type and training often very different from the typical medical mind. But it is part of one's purpose to show, if possible, that the historian must become a eugenist, just as the physician must, for eugenics needs and claims the work and help of both. CHAPTER XV