_Rules to be observed in Operations at Dr. Roberts' Clinic at the Woman's Hospital of Philadelphia._--After wounds or operations high temperature usually, and suppuration always, is due to blood poisoning, which is caused by infection with vegetable parasites called bacteria. These parasites ordinarily gain access to the wound from the skin of the patient, the finger nails or hands of the operator or his assistants, the ligatures, sutures, or dressings. Suppuration and high temperature should not occur after operation wounds if no suppuration has existed previously. Bacteria exist almost everywhere as invisible particles in the dust; hence, everything that touches or comes into even momentary contact with the wound must be germ-free--technically called "sterile." A sterilized condition of the operator, the assistant, the wound, instruments, etc., is obtained by removing all bacteria by means of absolute surgical cleanliness (asepsis), and by the use of those chemical agents which destroy the bacteria not removed by cleanliness itself (antisepsis). Surgical cleanliness differs from the housewife's idea of cleanliness in that its details seem frivolous, because it aims at the removal of microscopic particles. Stains, such as housewives abhor, if germ-free, are not objected to in surgery. The hands and arms, and especially the finger nails, of the surgeon, assistants, and nurses should be well scrubbed with hot water and soap, by means of a nail brush, immediately before the operation. The patient's body about the site of the proposed operation should be similarly scrubbed with a brush and cleanly shaved. Subsequently the hands of the operator, assistants, and nurses, and the field of operation should be immersed in, or thoroughly washed with, corrosive sublimate solution (1:1,000 or 1:2,000). Finger rings, bracelets, bangles, and cuffs worn by the surgeon, assistants, or nurses must be removed before the cleansing is begun; and the clothing covered by a clean white apron, large enough to extend from neck to ankles and provided with sleeves. The instruments should be similarly scrubbed with hot water and soap, and all particles of blood and pus from any previous operation removed from the joints. After this they should be immersed for at least fifteen minutes in a solution of beta-naphthol (1:2,500), which must be sufficiently deep to cover every portion of the instruments. After cleansing the instruments with soap and water, baking in a temperature a little above the boiling point of water is the best sterilizer. During the operation the sterilized instruments should be kept in a beta-naphthol solution and returned to it when the operator is not using them.