The healing magic of sleep is known to all. Sleeplessness is a punishment for so many different violations of nature's laws, that it is perhaps one of the most prevalent of humanity's innumerable sufferings. While most of the aspects of sleep and sleeplessness have received much attention from specialists in human physiology, the relation between sleep and coitus appears to be but little realised. Yet there is an intimate, profound and quite direct relation between the power to sleep, naturally and refreshingly, and the harmonious relief of the whole system in the perfected sex-act. We see this very clearly in ordinary healthy man. If, for some reason, he has to live unsatisfied for some time after the acute stirring of his longing for physical contact with his wife, he tends in the interval to be wakeful, restless, and his nerves are on edge. Then, when the propitious hour arrives, and after the love-play, the growing passion expands, until the transports of feeling find their ending in the explosive completion of the act, at once the tension of his whole system relaxes, and his muscles fall into gentle, easy attitudes of languorous content, and in a few moments the man is sleeping like a child. This excellent and refreshing sleep falls like a soft curtain of oblivion and saves the man's consciousness from the jar and disappointment of an anti-climax. But not only is this sleep a restorative after the strenuous efforts of the transport, it has peculiarly refreshing powers, and many men feel that after such a sleep their whole system seems rejuvenated. But how fare women in this event? When they too have had complete satisfaction they similarly relax and slumber. But as things are to-day it is scarcely an exaggeration to say that the majority of wives are left wakeful and nerve-racked to watch with tender motherly brooding, or with bitter and jealous envy, the slumbers of the men who, through ignorance and carelessness, have neglected to see that they too had the necessary resolution of nervous tension. Many married women have told me that after they have had relations with their husbands they are restless, either for some hours or for the whole night; and I feel sure that the prevalent failure on the part of many men to effect orgasms for their wives at each congress, must be a very common source of the sleeplessness and nervous diseases of so many married women.