It has been well said that the first intentional touching of a part of the skin of the loved one is already a half-sexual union; and this view is confirmed by the fact that such intimate bodily contacts, even when they occur between parts far distant from sexual organs, very speedily lead to states of marked excitement of these organs. Quite rightly, therefore, the pleasurable sensations aroused by means of cutaneous sensibility are regarded by Magnus Hirschfeld as the stages of transition along which the power of self-command and the capacity for resisting the impulses arising out of the transformation of sensory perceptions into movements and actions most commonly break down. He who avoids these first contacts, best protects himself against the danger of being overpowered by his sexual impulse, and of blindly following where that impulse leads--if, for example, he wishes to avoid intercourse with a person whom he suspects to be suffering from some venereal disease. Areas of skin more especially susceptible to sexual stimulation, the so-called erogenic areas, are those parts of the body where skin and mucous membrane meet--above all therefore the lips, but also the region of the anus, the female genital organs, and the nipples of the female breast. That in certain circumstances even the eye may be an erogenic zone is shown by the remarkable observation of Dr. Emil Bock, that in many female patients a gentle inunction of Pagenstecher’s ointment into the eye gives rise to changes of countenance showing that a sexual orgasm is occurring. The contact of the lips in the =kiss= is one of the most powerful stimuli of love.[7] An Arabian author of the sixteenth century (Sheikh Nefzawi) in his work, “The Perfumed Garden,” an Arabian _ars amandi_, alludes to this fact. He quotes the verses of an Arabian poet: “When the heart burns with love, It finds, alas, nowhere a cure; No witch’s magic art Will give the heart that for which it thirsts; The working of no charm Will perform the desired miracle; And the most intimate embrace Leaves the heart cold and unsatisfied-- If the rapture of the kiss is wanting.” The physiologist Burdach, influenced by the then dominant natural philosophy of Schelling, defined the kiss as “the symbol of the union of souls,” analogous to “the galvanic contact between a positively and a negatively electrified body; it increases sexual polarity, permeates the entire body, and if impure transfers sin from one individual to the other.” Goethe has very perspicuously described sexual union in a kiss: “Eagerly she sucks the flames of his mouth: Each is conscious only of the other.” And Byron writes: