A mysterious interest has indeed always attached to these functions. From the Mosaic law to Raciborski, from the denunciations of the school-men to the rhapsodies of Michelet, they have been invoked in every theory on the nature of women; that is, in every theory on the organization of society. In virtue of them, the woman has been considered, now unclean, now angelic, now touchingly (but irredeemably) helpless. In this connection, the association of ideas has been almost always too powerful and too varied to admit of a dispassionate examination of facts. Yet to-day, as already said, the old conclusions may be urged with even greater force than before, because apparently based exclusively upon such cool and impartial investigation. The issue is certainly serious. From all sides surges testimony to the importance of physical conditions as the basis of mental and social life. According to many, it is by the absence of a few grains of iodine from the water of drinking fountains, that the people of the Alps are turned into _cretins_. According to others, it is by the presence of a few grains of ergot in the bread, that the people of Tuscany lose their limbs in gangrene. Endemics of abortion depend on the impalpable vapors that arise from the quicksilver mines of Spain. So delicately poised are the forces of life, that an apparent trifle suffices to entirely turn the scale. It is therefore not _a priori_ improbable, that the marked peculiarities of physical organization that distinguish the female sex, should determine a radically different mode of mental existence, and exact radically different conditions of mental activity.