AN'TISEP'TIC (anti + Gk. cir-str, s(Tein, to make rotten, to cause decay). In the arts, any substance which arrests fermentation and decay: in medicine, any agent which arrests the de velopment and growth of micro-organisms. A germicide is a substance or agency which destroys these micro-organisms. A disinfectant destroys the organisms, and at the same time removes the noxious products of fermentation and putrefac tion. The conditions which favor putrefactive change are a moderate degree of warmth, air, and the presence of moisture and micro-organ isms. Sleasures which tend to limit the action of any of these agencies arc antiseptic in char acter. Cold acts as an antiseptic, by bringing the article to be preserved to a temperature at which the putrefactive bacteria can no longer act. In the preservation of canned goods another princi ple is employed, that of exclusion of air. The cans, with their contents, are heated, and when all air has been expelled the tops are soldered on. The principle of excluding moisture is em ployed in the processes of drying meats, fruits. and vegetables. The action of micro-organisms is often combated dinvtly by the introduction into preserved foodstuffs of such antiseptic sub stances as boric and salicylic acids and formal dehyde. They are considered injurious., however, and their use is forbidden by law in many States. Besides the antiseptics proper, a number of the more common substances, such as common salt, sugar, alcohol, and saltpetre. are used in food preservation. On the other hand, antiseptics are used for other purposes besides the preserva tion of foodstuffs. Thus the preservation of sizes used in paper-making is effected by the addition of sulphurous acid, and the preserva tion of the commercial gums and pastes by such antiseptic's as carbolic acid and oil of winter green. The preservation of wood from decay by impregnation with tar, creosote, carbolic acid.
and corrosive sublimate is also practiced to a considerable extent.
In scientific laboratories antiseptics like alco hol and formaldehyde are largely employed in the preservation of anatomical and biological specimens. In surgery, the application of anti septics, first introduced by Sir Joseph Lister, is a matter of greatest moment. It is an under standing of the use of antiseptic and germicidal agencies that has brought about the remarkable advances made by this branch of the healing art since 1880. The condition that is sought for in every surgical operation to-day is asepsis, or surgical cleanliness. When a substance is aseptic it is free from all septic micro-organisms. Such a state is made possible by the use of antiseptics and germicides. Instruments are generally ren dered aseptic or sterile by boiling in water, by dry heat, by steam, or by washing with the chem ical antiseptics, or by exposing them to moist formaldehyde vapors: dressings, by dry heat or by steam at ordinary atmospheres or under pres sure: ligatures, by prolonged immersion in alco hol or other antiseptic solutions; and the skin of the patient at the site of the operation, by application, after meehanical cleansing, of a solu tion of carbolic acid or of corrosive sublimate. The chemical substances most commonly em ployed as antiseptics in medicine are acid, the bichloride and the biniodide of mercury, formaldehyde. free chlorine, iodine, potassium permanganate, iodoform, and boric acid, and to a lesser extent the vegetable substances thymol, menthol, and eucalypti)]. Further el ill sideration of antiseptics may be found in The Rules of Asep tic and Antiseptic Surgery (New York, 1888), by Gerster: and in the article "Antiseptics," in Wood's Reference Handbook of the Medical Sci ences. See BACTERIA; :MICROBE; Koch, ROBERT;