When abortion is criminally induced, it generally takes place between the _fourth and fifth months_, that is, about the time the woman becomes certain of her condition. The Causes of Abortion are-- 1. Natural or Accidental.--(_a_) Maternal--belonging to the mother; (_b_) Fœtal--belonging to the ovum. 2. Violent.--(_a_) Mechanical; (_b_) Medicinal. 1. Natural or Accidental (_a_) =Maternal.=--Among the maternal causes may be mentioned excessive lactation; any irritation of the rectum or bladder; loss of blood, which, by increasing the amount of carbonic acid in the blood, acts as an excitant to the spinal cord; excessive irritability and excitability of the uterus, &c. Certain states of the system conduce to abortion--albuminuria, syphilis, certain fevers, scarlet fever, smallpox, &c. Abortion may become habitual in some women. Great joy or sudden sorrow have not infrequently been the cause of abortion. The tendency to abortion is greatest at the menstrual periods, that is, at the time when, had not the woman become pregnant, menstruation would have taken place. Slight causes acting at these times are very liable to produce abortion. (_b_) =Fœtal.=--The death of the ovum, or a diseased condition of its uterine coverings, or of the placenta, probably of an inflammatory nature. 2. Violent (_a_) =Mechanical.=--Under this head may be mentioned the passage of certain instruments into the cavity of the womb, and the rupture by violence of the membranes which surround the fœtus; also the injection of fluids into the uterus. A medical man practising in Yorkshire informed Husband that so great was the dread of large families, that he knew of several ladies who, if they went a day over their monthly period, passed a catheter into the uterus, with the desired result. “It was wonderful,” he added, “how clever they were.” In India a twig of the _Euphorbium nivulia_, anointed with assafœtida, is used for the same purpose. “The fœtus is never delivered alive, but there is said to be no great danger to the woman” (Chevers). Women may use hairpins, knitting-needles, and the idea is to pass the instrument “until blood comes,” which is accepted as a sign that abortion will be sure to follow. In some cases it is by no means easy to procure abortion, and women have been known to undergo a considerable amount of violence without abortion taking place. In some women, however, on the other hand, the slightest violence--such, for instance, as slipping from a step or low chair--will cause them to abort.