in ignorance. It is not perhaps very useful to describe human cavalage, which is not strictly a cavalage, as the woman is attacked from the front. Veritable cavalage has been, as one knows, praised by Lucretius, although, it has, and this detracts nothing from its merits, an air frankly animal; it is the form of love called by the theologians _more bestiarum_ and by Lucretius _more ferarum_ which is the same thing: Et quibus ipsa modis tractetur blanda voluptas, Quoque permagni refert; nam more ferarum, Quadrupedumque magis ritu, plerumque putantur Concipere uxores, quia sic loca sumere possunt, Pectoribus positis, sublatis semina lumbis. This mode, considered by Lucretius as the more favourable to fecundation, is that of most mammifers, of nearly all insects and of many animal families. Apes great and small know no other. The architecture of their bodies would make face to face copulation very difficult. One must not forget that their upright position is never more than momentary, even in orangs and chimpanzees; they are not much better equilibrated than bears, much less so than kangaroos, marmosets[1] and squirrels; even when they stand up one feels that they have four feet. Love among them is not free from the seasons, and although they are libidinous all the year, they do not seem fit for generation save through the weeks of their rutting time: then their genital organs acquire a permanent rigidity; the udders of the females, ordinarily as small as those of the males, only swell during this period. There is, therefore, a vast difference, from the sexual standpoint, between man and the great apes, his anatomic neighbours. Man even in the humblest species has mastered love and made it his daily slave, at the same time that he has varied the accomplishments of his desire and made possible its renewal after brief interval. This domestication of love is an intellectual work, due to the richness and power of our nervous system, which is as capable of long silences as of long physiological discourses, of action and of reflection. The brain of man is an ingenious master which has managed, without possessing any very evident superiority, to get out of the other organs work of the most complicated sorts, and most finely-sharpened pleasures; its (the brain's) mastery is very feeble in quadrumanes and other animals; it is very strong in insects as will be explained in a following chapter.