=Abdominal Cavity.=—Often it will be found necessary to do cavity work in the abdominal cavity. Gases may arise causing a distention of the abdominal wall, resulting in purging from the mouth and nose. This gas is the result of putrefaction and fermentation in the alimentary canal. When one of the principle arteries is injected, the fluid finds its way to the minute capillaries of the organs of the abdominal cavity, including the stomach and the intestines. It must be remembered that often there is a great amount of undigested food and fecal matter in the stomach and intestines. The only way the fluid which is in the minute capillary circulation of the stomach and intestines, is able to reach the inside of those organs and come in contact with the undigested food and the fecal matter is by soaking through the mucous wall. No doubt a certain quantity of the fluid does soak through, and when it does, if there is not much undigested food or fecal matter in these parts, disinfection will be accomplished and it is in these cases that we do not have any trouble with distentions of the abdomen. When however, there is a great amount of undigested food and fecal matter inside the stomach and the intestinal tract, it is only obvious that enough fluid can not possibly soak through to disinfect, and consequently a host of putrefactive, and fermentative germs will begin their work, with the formation of gases and the distended abdomen, and perhaps purging from the mouth and nose. To prevent the formation of gas now which has arisen, a second injection will do no good. More drastic measures will have to be used. One method that has long been in vogue is the use of the trocar.