The extreme sensitiveness of the skin, the readiness with which its stimulation reverberates into the sexual sphere, clearly brought out by the present study, enable us to understand better a very ancient contest--the moral struggle around the bath. There has always been a tendency for the extreme cultivation of physical purity to lead on to the excessive stimulation of the sexual sphere; so that the Christian ascetics were entirely justified, on their premises, in fighting against the bath and in directly or indirectly fostering a cult of physical uncleanliness. While, however, in the past there has clearly been a general tendency for the cult of physical purity to be associated with moral licentiousness, and there are sufficient grounds for such an association, it is important to remember that it is not an inevitable and fatal association; a scrupulously clean person is by no means necessarily impelled to licentiousness; a physically unclean person is by no means necessarily morally pure. When we have eliminated certain forms of the bath which must be regarded as luxuries rather than hygienic necessities, though they occasionally possess therapeutic virtues, we have eliminated the most violent appeals of the bath to the sexual impulse. So imperative are the demands of physical purity now becoming, in general opinion, that such small risks to moral purity as may still remain are constantly and wisely disregarded, and the immoral traditions of the bath now, for the most part, belong to the past. SMELL. I. The Primitiveness of Smell--The Anatomical Seat of the Olfactory Centres--Predominance of Smell among the Lower Mammals--Its Diminished Importance in Man--The Attention Paid to Odors by Savages.