Prolapse of cord or an extremity with a presentation of the head. Placenta previa. Transverse position after the seventh month. Any condition requiring rapid delivery. CONDITIONS.—Cervix effaced and os dilated. Uterus not in tetanus nor contracted down over the child. The fœtus must be movable. The head should not be engaged. The _Walcher position_ is produced by bringing the patient down to the end of the table so that the sacrum rests upon the edge. The thighs and legs are allowed to hang down of their own weight and the patient is restrained from falling off by traction upwards on the axillæ. In the Walcher position the diameter of the pelvic inlet is increased from ⅓ to ½ inch (1 cm.) and thereby the delivery of heads that otherwise could not pass becomes possible. In addition to the Walcher position other measures may be required to help the head through. Thus, traction from below may be carried to the limit of safety and in spite of the Walcher position the head may not pass the inlet. Then pressure from above is added. This maneuver will have to be executed in many cases by the nurse. The fingers palpate the head above the pubes. Then one or both fists are placed upon the abdomen over the head and force is exerted to crowd the head down into the pelvis. This is known as the _Wiegand compression_. For the operations destructive to the child, craniotomy or decapitation, the same arrangements are made. [Illustration: Fig. 83.—The Walcher position. (American Text Book.)] =Cranioclasis= is the crushing of the fœtal skull so that in its reduced condition the child can be delivered and the mother’s life spared. In addition to the solutions, the only instruments required are the Auvard cranioclast, a Naegele perforator, and a douche bag with glass, or any tip that can be sterilized. In many of these cases, _both_ mother and child could be saved if seen early enough to have a Cæsarean operation. =Decapitation= is done to save the maternal life in cases of transverse or shoulder presentation. The preparations are the same as already described for forceps and version and the only instrument needed is a Braun blunt hook. (Fig. 73.) [Illustration: Fig. 84.—The Wiegand compression of the child’s head to force it into the pelvis. (Hammerschlag.)] =Cæsarean section= is the delivery of the child through an opening in the abdomen. It is made necessary by contraction of the pelvic bones, or by the presence of a fleshy or bony mass which diminishes the size of the inlet. It may be required on account of the closure of the vagina or cervix by scars or on account of urgent conditions of the mother, such as eclampsia, heart disease, and sometimes placenta previa. The technic is simple, but good judgment must be used in knowing when to do it. Many operators find it so easy that they prefer it to the harder but safer obstetrical operations.