Appliances that are injured by moist heat or by steam may be sterilized by thorough washing and soaking in a solution of bichloride of mercury (1:1000). It is useful to keep a large vessel of such a solution on hand, in which apparatus that is not injured by the bichloride may be placed. =The Water.=--The water used during the operation, for washing the wound, the abdominal cavity, the sponges, and the hands of the operator and assistants, should be sterilized by boiling or by distillation. The water should be boiled for two hours a day on two consecutive days, or it should be boiled under pressure as in some of the modern water-sterilizers. If the water contain a perceptible sediment, it should first be filtered. Very convenient water-sterilizers are made, from which the water may be drawn of any desired temperature, after having been both filtered and sterilized by heat. There should always be a large quantity of sterile hot water at hand. Water below the temperature of the body should not be introduced in the peritoneal cavity, and pads brought in contact with the intestines should be wrung out of hot water. About fifteen gallons of sterile water are usually required in an abdominal operation. The water should be preserved in sterile pitchers, basins, or other receptacles. Glass flasks are very convenient for containing the water with which the abdomen or pelvis may be washed out. The water may be poured directly into the abdomen from the flask. The flask should be plugged with non-absorbent cotton to prevent the entrance of dust. Some operators prefer to use a normal salt solution (sodium chloride gr. 90 to water ℥xxxiiiss) for washing out the peritoneum. Such a solution is probably less irritating to the peritoneum than plain water. If the flasks are used for containing the water, it may be boiled in them, and then preserved by plugging with absorbent cotton until required at the operation. The temperature of the water used for abdominal irrigation should be 100° to 115° F. =Sponges.=--In the minor operations about the vagina or uterus the field of operation may be kept clean by irrigation with sterile water or by the use of sponges. Small sponges in holders are commonly used. These sponges, after being washed free of sand and bleached if necessary, may be sterilized by soaking for twelve hours in a solution of bichloride of mercury (1:500). They should then be rinsed in warm water and preserved in a 3 per cent. watery solution of carbolic acid, which should be changed every week. Artificial sponges, or gauze sponges, are the most convenient in abdominal surgery. They are cheap, and may be destroyed after each operation, and they are very easily and certainly sterilized in the steam sterilizer. Good marine sponges are so expensive that but few operators destroy them after they have been once used. The cleansing and sterilization of such sponges are tedious and uncertain. The gauze sponges answer every purpose.