=Hydrogen Peroxid= (_Love_).—A powerful nontoxic antiseptic. It is used in five- to fifty-per-cent aqueous solutions, and is most efficacious in suppurating wounds, in which it destroys the microörganisms of pus. It foams actively when brought in contact with the latter, and is said to render a wound aseptic by one or two applications. A standard preparation of known strength must be obtained, however, to get good results. =Iodin.=—A very powerful nonirritating antiseptic. Used especially for washing wounds. The proper solution is made by mixing two drams of the tincture (℥j iodin to ℥Oj alcohol) with one pint of warm water (Bryant). The one-per-cent solution of the trichlorid is equal in its effectiveness to a four-per-cent carbolic solution (Langenbuch). =Lysol.=—Very similar to creolin, both in composition and effect. Is nontoxic, and employed in two-per-cent aqueous solution. Appears as a soapy liquid, and forms a clear solution with water. =Potassium Permanganate.=—An active disinfectant, quickly destroying the odor of decomposition, and for that reason is splendid for the washing out of foul wounds. It is nonpoisonous, and has moderate antiseptic power—the five-per-cent solution killing resting spores. Its effect is limited to a short time only, as the secretions from a wound decompose and precipitate it into an inactive form. It is employed in aqueous solution, differing in color from light ruby to dark brown; that is, 1-1,000 to 1-100. The solution, known as Condy’s Fluid, has a strength of 1-1,000. =Salicylic Acid.=—A derivative of carbolic acid, and an effective nonirritating antiseptic. It is only slightly soluble in cold water, 1-300. When combined with boric acid, it becomes more soluble. This antiseptic cannot be used for instruments, however, as it corrodes them. Its other objections are that it evaporates quickly from dressings and that it is expensive. =Sodium Chlorid.=—Is a common agent used for the irrigation of putrid wounds in two-per-cent solution. For irrigation during aseptic operation and for covering sterilized sponges it is used in eight-per-cent solution (v. Esmarch). This corresponding to the normal salt solution. Its use in connection with corrosive-sublimate solutions (Maas) has been referred to. =Thymol= (_Rancke_, _Bouillon_, _Paquel_).—The aromatic principle of thyme. Efficient as an antiseptic in 1-1,000 aqueous solution. It has a pleasant odor, and is nonirritant and nontoxic. Exhibited in colorless crystals. An excellent solution is prepared as follows: ℞ Thymol 20 parts Alcohol 10 ” Glycerin 20 ” Aquæ 1,000 ” It is used especially in washing out cavities where carbolic acid cannot be employed, and for cleansing mucous membranes preparatory to operation.