All instruments should be of modern make, devoid of clefts or grooves, and having separating locks when possible. Wooden or ivory handles should be entirely discarded. They should first be rendered free of dirt or dried blood by scrubbing briskly with a stiff nailbrush and hot water; then dried and placed in the sterilizer. The immersed instruments are boiled for five or ten minutes. There are many of such sterilizing apparatuses to be obtained, all made on the same plan, however, and consist of a copper or brass box and cover well nickel plated. Folding legs are placed beneath. A perforated tray is placed within for the immersion of instruments. An alcohol lamp with asbestos wick furnishes the heat. One per cent of carbonate of soda added to the water prevents them from rusting. The simple subjection of instruments to carbolic-acid solutions or antiseptics of like nature is useless. (Gärtner, Kümmel, Gutch, Redard, and Davidsohn.) From the sterilizer the instruments are placed in a glass tray containing a one-per-cent lysol solution. Knives, needles, and scissors should be immersed in a tray with alcohol, as a great number of antiseptics destroy their cutting edges. Glass or porcelain trays are best for this purpose. A sterilized towel being placed in the bottom of each for the better placing of instruments. After operation all instruments should again be scrubbed with soap and hot water, immersed a moment in boiling water or a jet of live steam, dried with an aseptic cloth, and returned to the case. A very effectual means of rendering instruments sterile is to place them in a metal box and bake them in the ordinary oven (200° F.) for one hour. To preserve needles Dawbarn advises keeping them in a saturated solution of washing soda. Albolene has an unpleasant oiliness, but is otherwise good. Calcium chlorid in absolute alcohol is efficacious, but expensive. All rust accumulating on instruments must be carefully removed with fine emery cloth; this, however, is unnecessary if the soda solution is used as previously mentioned. It is well to occasionally dip the instruments (holding them with an artery forceps) into boiling water as they are used during operation. [Illustration: FIG. 8.—INSTRUMENT STERILIZER.] PREPARATION OF THE SURGEON AND ASSISTANTS CARE OF THE HANDS The hands of the surgeon and his assistants must always be thoroughly prepared before operation or dressing a wound. The mere immersion of the hands into an antiseptic solution is not sufficient to remove germ life. The oily secretions of the skin and its folds, as well as the cleft about the nails and the nails themselves, are common carriers of infection and are cleansed only by the vigorous method of scrubbing with soap and water and then rendered aseptic by the use of proper media.