Sex efficiency through exercises : special physical culture for women / by Th. H. van de Velde ; [photos, by E. Steinemann].

up towards his body than is usual, he benefits from her ability to execute a greater variety of pelvic movement, i.e., to impart a greater range of sensation than he has at his own command, because of the distinctive genital structure of the male. For, in man, the organ of sex is an external limb, attached to the pelvis and without much range of indepen- dent spatial movement. This fact limits him to rhythmic backward and forward movements, which may be gentle or vehement, but have few possible variations. But the woman's receptive sheath is within her pelvis, and this enables her not only to sway to and fro as he does, but also— if her pelvic muscles are well trained, firm yet elastic—to exercise pressure on shaft or tip of the male organ at will and thus impart fresh and keener stimulus. Also, in the same manner, to apply varied friction and pressure to her own organs both internal (vagina and portio) and external (clitoris). She is also able to perform other than longitudinal movements ; she may vibrate or undulate her body sideways and thus add a new series of sensations. This faculty is most vividly realised in the really adept performance of coitus astride. If the woman is physiologically and technically able to do justice to this attitude—in which she plays the active part—the steady but vibrant pressure and friction of portio vaginalis and glans penis gives far keener and subtler pleasure to both herself and her partner than anything possible in " medial" coitus. The summit of sensation is attained by a very gentle but steady rotation of the pelvic periphery from the portio vaginalis as a centre ; the portio presses against both corona glandis and frenulum prcaputii alternately, with a circular movement which does not provoke a premature climax, but prolongs the most exquisite intensity of pleasure. Of course, this type of sensation means full length penetration, as well as great skill on the woman's part. And such full length penetration always implies a certain risk of undue strain or even rupture. But, as in equitation, the woman's body is above the man's, she is able to alter her position or call a halt at the danger signal of any pain. The sedentary attitudes, both posterior and especially anterior, are also well adapted for pelvic mobility