"The burden of proof rests with the state to show that the means used were not necessary to preserve the life of the woman in question; and the absence of necessity may be determined from circumstantial evidence. But the burden of proof as to the advice of physicians would not fall within the rule controlling the production of proof as to negative matters in general, and would rest with the accused; though it may be proved by a preponderance of the evidence and need not be established beyond a reasonable doubt. But either that the act was necessary to preserve the life of another, or that it was advised by physicians to be necessary for that purpose, is of equally good defence; and the destruction of the child need not have been both necessary and advised by physicians. And statutes of this class apply only in cases in which the death of the mother could reasonably be expected to result from natural cause, unless the child was destroyed, and do not apply to a case in which the mother threatened suicide unless she was relieved from her trouble." CHAPTER VI ECTOPIC GESTATION Ectopic Gestation, called also extrauterine pregnancy, is gestation outside the uterus in the adnexa or the peritoneal cavity. Pregnancy in the horn of an abnormal or rudimentary uterus is classed with ectopic gestation because the effects are similar, although pregnancy at times in a rudimentary uterus goes on to term normally. The uterus is in the pelvic cavity, between the bladder and the rectum, and above the vagina, into which it opens. It is a hollow, pear-shaped, muscular organ, somewhat flattened, and about three inches long, two inches broad, and an inch thick. The fundus or base is upward, and the neck is downward. Passing horizontally out from the corners or horns of the uterus, which are at the fundus, are the two Fallopian tubes, one on either side. These are about five inches in length and somewhat convoluted. They are true tubes, opening into the uterus, and they are about one-sixteenth of an inch in diameter throughout the greater part of their extent. The ends farthest from the uterus are fringed and funnel-shaped; and this funnel end, called the Infundibulum or Fimbriated Extremity, opens into the abdominal or peritoneal cavity. Near the Fimbriated Extremity of each tube is an Ovary, an oval body about one and a half inches long by three-quarters of an inch in width. For convenience in description, each tube is divided into four parts: (1) the Uterine Portion, which is that part included in the wall of the uterus itself: it extends from the outer end of the horn into the upper angle of the uterine cavity, and its lumen is so small that it will admit only a very fine probe; (2) the Isthmus, or the narrow part of the tube which lies nearest the uterus: it gradually widens into the broader part called (3) the Ampulla; (4) the Infundibulum, or the funnel-shaped end of the Ampulla. One of the fimbriae, the Fimbria Ovarica, is longer than