When knowledge and love together go to the making of each marriage, the joy of _that new unit, the pair_ will reach from the physical foundations of its bodies to the heavens where its head is crowned with stars. _Addition_ 1 (_to page_ 49) A curious rigidity of mental and physical capacity seems to characterise some excellent and well-meaning people, and among those whose marriages unaccountably fail to reach just that height of perfection in a physical sense which they may intellectually desire, are those who are either entirely ignorant that sex union may be accomplished in many various positions, or those who consider any other position but the most usual one to be wrong. Yet, curiously enough, it sometimes comes to light that a pair do not even know the usual position, and in my own experience several couples who have failed to have children, or have failed to obtain the complete delight of union, have revealed that the woman did not know that it is not only her arms which should embrace her lover. Consequently, entry was to him both difficult and sometimes impossible. In addition to this, the encouragement of that spontaneous movement which comes so naturally to those who are highly stirred, needs in far too many of our moderns to be cultivated. A pair should, impelled by the great wave of feeling within them, be as pliable as the sea-plants moved by the rushing tides, and they should discover for themselves which of the innumerable possible positions of equilibrium results in the greatest mutual satisfaction. In this matter, as in so many others of the more intimate phases of sex life, there should not harden a routine, but the body should become at the service of intense feeling a keen and pliable instrument. _Addition_ 2 (_to page_ 83)