Hirschsprung pointed out this, indeed, many years ago, on the ground of his own experience. And see Rohleder, op. cit., pp. 44-47.
In many cases, of course, the physical precocity is associated with precocity in sexual habits. An instructive case is reported (Alienist and Neurologist, October, 1895) of a girl of 7, a beautiful child, of healthy family, and very intelligent, who, from the age of three, was perpetually masturbating, when not watched. The clitoris and mons veneris were those of a fully-grown woman, and the child was as well informed upon most subjects as an average woman. She was cured by care and hygienic attention, and when seen last was in excellent condition. A medical friend tells me of a little girl of two, whose external genital organs are greatly developed, and who is always rubbing herself.
R. T. Morris, of New York, has also pointed out the influence of traditions in this respect. "Among boys," he remarks, "there are traditions to the effect that self-abuse is harmful. Among girls, however, there are no such saving traditions." Dr. Kiernan writes in a private letter: "It has been by experience, that from ignorance or otherwise, there are young women who do not look upon sexual manipulation with the same fear that men do." Guttceit, similarly, remarks that men have been warned of masturbation, and fear its evil results, while girls, even if warned, attach little importance to the warning; he adds that in healthy women, masturbation, even in excess, has little bad results. The attitude of many women in this matter may be illustrated by the following passage from a letter written by a medical friend in India: "The other day one of my English women patients gave me the following reason for having taught the 17-year-old daughter of a retired Colonel to masturbate: 'Poor girl, she was troubled with dreams of men, and in case she should be tempted with one, and become pregnant, I taught her to bring the feeling on herself—as it is safer, and, after all, nearly as nice as with a man.'"
H. Ellis, Studies in the Psychology of Sex, volume ii, "Sexual Inversion," Chapter IV.