The frequent practice of self-abuse occurring in little children from the age of two years old, clearly illustrates the fallacy of endeavouring to separate mind and body in educational arrangements or systems of medical treatment. In the very young child those essential elements of reproduction, semen and ova, which give such mighty stimulus to passion in the adult, are entirely latent. Yet we observe a distinct mental impression possible, leading to unnatural excitement of the genital organs. This mental impression, growing with the growth of the child, produces an undue sensitiveness to all surrounding circumstances which tend to excite this cerebral action. Touch, sight, and hearing become avenues to the brain, prematurely opened to this kind of stimulus. The acts of the lower animals, pictures, indecent talk, which glide over the surface of the mind in a naturally healthy child, excite self-conscious attention when habits of self-abuse have grown up unchecked. The mind is thus rendered impure, and the growing lad or girl develops into a precocious sexual consciousness. At school a new danger arises to children from corrupt communication of companions, or in the boy from an intense desire to become a man, with a false idea of what manliness means. The brain, precociously stimulated in one direction, receives fresh impulse from evil companionship and evil literature, and even hitherto innocent children of ten and twelve are often drawn into the temptation. From the age when the organs of reproduction are beginning slowly to unfold themselves for their future work, the temptation to yield to physical sensation or mental impression increases. The inseparable relation of our moral and physical structure is seen in full force at the age of twelve or fourteen. Confirmed habits of mental impurity may at any age destroy the body from the physical results of such habits. My attention was painfully drawn to the dangers of self-abuse more than forty years ago by an agonized letter received from an intelligent and pious lady, dying from the effects of this inveterate habit. She had been a teacher in a Sunday-school, and the delight of a refined and intelligent circle of friends. But this habit, begun in childhood in ignorance of any moral or physical wrong which might result to her nature, had become so rooted that her brain was giving way under the effects of nervous derangement thus produced, whilst her will had lost the power of self-control. It will thus be seen that there are two grave dangers attending the practice of masturbation.