The peritoneum should be caught with forceps and drawn forward. The assistant should catch the peritoneum with a second pair of forceps at a point about ⅓ or ½ inch to the side of the first pair, and the small fold of peritoneum thus produced should be incised with the knife. As soon as the smallest opening is made in the peritoneum the air rushes in and the intestines and omentum fall back. The opening is then enlarged with the knife or scissors. The greatest care must be exercised in those cases in which the omentum or the intestines are adherent to the anterior abdominal wall. The experienced operator usually observes indications of such a condition as soon as he has passed through the linea alba. The tissues are more rigid and unyielding than normal, and the peritoneum cannot be readily picked up with the forceps. In such cases the operator should proceed very slowly, and if necessary should enlarge the outer incision and enter the peritoneum at a point above or below the area of adhesion. =Exploration of the Abdomen.=--Having opened the peritoneum, the operator should insert two fingers (the middle and the index finger of the left hand) and should carefully examine the condition to be treated. If necessary, he should retract the edges of the incision, and should place the patient in the Trendelenburg position, in order to make an ocular examination. It is always advisable to make a preliminary investigation of this kind before proceeding with the operation. In this way the diagnosis will be corrected and complications which must be treated will be determined. It may be found that what was thought to be a cyst is in reality a uterine fibroid or perhaps a normal pregnancy; or the surgeon may discover a hopeless condition, such as extensive cancer or peritoneal papilloma, for which further operation will be useless.