Sexual Development.-- Sexual development goes on during all the years of childhood, but is not complete in the female sex until between the twenty-second and the twenty-fifth year. If the child has no inherited taint, and has been properly educated morally, physically, and intellectually, it must follow that the structural development of the pelvic organs has been normal; and normal organs always perform their functions perfectly. The commencement of the ovarian function does not cause any more profound change in the system and habits than does dentition. The various epochs of life are generally spoken of as if they were paroxysmal-- as though they were separated by some tremendous chasm, which had to be leapt over or fallen into. Nature makes no such egregious blunders; preparations for every change in life have been going on for a very long time before the evidences of such change become manifest. In a healthy girl the psychic and physical changes incident to puberty occur so gradually as to escape the girl's own notice. The first and, if the girl has not been properly prepared for it, always startling change is the appearance of the menstrual flow. The mother who has not told her daughter of this coming change in her life before it is due has committed a serious error; it is no uncommon occurrence for girls who know nothing of this function to get into a tub of cold water to stop the flow; and if they stay in long enough, it generally does stop, and the girl's health may be ruined for life. The opinion of Dr. Ely van de Warker is that "if healthy ovulation is the outcome of healthy childhood, the function will obey the law of periodicity year by year, and all this time the young woman will be able to sustain uninterrupted physical and intellectual work as well as the young man. Not that the laws of health may be violated with impunity at puberty or any other time of a woman's life; but a law of health is no more binding upon a young woman than it is upon a young man; and there really is no such thing as one law for women and another for men." Age of Puberty.-- In the temperate regions the age of puberty is reached between the ages of twelve and fourteen years. The girl is then said to be nubile; that is, as soon as menstruation appears it is possible for her to bear children; but she is by no means sufficiently developed to do so, as she herself will not be completely developed physically or mentally before the age of twenty-two or twenty-five years.