It is seldom necessary to assist the shoulders by applying any extractive force to the head, for in the course of a minute or two the uterus generally resumes its activity and expels it: on the other hand, when the shoulders pass through the os externum, the right hand should be in readiness to prevent the body of the child from being born too rapidly: the uterus can scarcely be emptied of its contents too gradually, for by this means it contracts equably, powerfully, and permanently, and throws off the placenta without difficulty; whereas, if suddenly evacuated, it frequently becomes powerless for a time, or if contraction does take place, it is so irregular and incomplete as to endanger partial separation, retention of the placenta, and hæmorrhage.[70] If, however, the cord be twisted exceedingly tight round the child's neck, and imbedded so deeply into the skin, as to render it impossible to push the coil over the shoulder, it may become necessary to divide it in order to let the child pass, in which case the practitioner must seize the divided ends as well as he can, and apply a ligature the instant the child is born. We believe that this is rarely, if ever, necessary; for in proportion as the child advances, so does the fundus descend, and thus relieves, in some measure, the tension to which the cord is exposed. This subject, however, belongs rather to the third species of dystocia, to which we must therefore refer. _Birth of the child and ligature of the cord._ As soon as the child is born, we must place it in such a position as will enable it to breathe with ease. The sudden exposure to the external air is generally sufficient to excite respiration; if not, a gentle pat on the nates, or blowing suddenly in the face, will usually succeed: if, however, the child still remains insensible, recourse must be had to those means which are recommended under the head of _Asphyxia neonatorum_. The cord should not be tied until it has ceased to beat, for unless the circulation be well established in its new course, the breathing is apt to stop, and the child relapse into insensibility: the cord should be tied about three inches distant from the umbilicus; it should be applied tightly, because otherwise it is apt to become loose, as the cord grows flaccid. In tying the ligature, one hand should be supported against the other to prevent giving the cord any jerk in case the ligature breaks; we are able also by this means to tie it more firmly.