Haroun-el-Raschid to Charlemagne were many perfumes. In the middle ages, among princes and men of highest rank, they washed their hands with rose-water, before and after eating; some even had fountains from which aromatic waters flowed. At this period, too, it was the custom to carry the dead to their burial-place with uncovered face, and to place little pots full of perfumes in the coffins. The French monarchy always showed an unrestrained passion for enjoyments of this nature, which seemed created as a necessary attendant upon all others. Marshal Richelieu had so extravagantly indulged his passion for perfumes under every form, that he had lost the perception of them, and lived habitually in an atmosphere so loaded with scents that it made his visitors ill. Madame Tallien, coming from a bath of juice of strawberries and raspberries, used to be gently rubbed with sponges saturated with perfumed milk. Napoleon I. every morning poured eau-de-Cologne, with his own hands, over his head and shoulders.
Above all these questions which we have just skimmed, there rises another, of a graver and more mysterious kind, one which occurs at the end of all studies that treat of sensation, and with regard to which some reflections will not be out of place here. To what, outside of us, do those sensations which we experience within us correspond? What relation is there between the real world and that image of the world shadowed in our soul? In the special case we are concerned with, what is it in these substances which is the cause why they affect our sense of smell? It seems certain, in the first place, that odor in itself, so far as it is odor, is a mere figment of our mind. Contemporaneous physiology proves that excitement of the nerves of sensation is followed, in each one, by the sensation that corresponds with each. When we electrify the eye, we call up in it an appearance of light; when we electrify the tongue, we produce in it a sensation of taste; when we electrify the inside of the ear, we provoke in it the effect of a sound. So, too, a similar excitement, electric or otherwise, of the olfactory nerves, creates in our mind the sensation of smell, even though no odorous molecule takes part in the phenomenon. Sensation, therefore, seems to depend chiefly on the nature of the sensitive nerve. The external world seems to contribute to it only by setting in motion the nerve-fibres. Even this condition of an impulse impinging from without is not indispensable, since, in sleep and in madness, we experience sensations of smell which, by the testimony of our other senses, answer to no external agent. Still, we believe that we can distinguish cases of hallucination from cases of true perception; still, we maintain that there are, outside of ourselves, distinct causes of our distinct sensations. No skepticism has prevailed, nor will prevail, against this testimony of the most powerful evidence which exists in