+Iodoform.+ The action of iodoform is not due directly to its ability to destroy germs but to its undergoing decomposition in the presence of moisture, liberating iodin and thus rendering inert ptomains that have resulted from the growth. +Iodoform Powder+ is rapidly absorbed by the skin and fatal cases of iodoform poisoning have occurred from treating burns with it. Iodoform is also used in ointment form and in suppositories. As it is insoluble in water it is commonly used in a 10 per cent. emulsion. The gauze is also greatly used. The symptoms of iodoform poisoning are: delirium; odor of iodoform on the breath; presence of iodoform in the urine; eruption over the skin, and finally, coma. Iodoform is also capable of producing a localized dermatitis, with great irritation, and must therefore be used with care on all delicate skins. +Aristol+, a substitute for iodoform, is a compound of iodin and thymol, producing no toxic effects and having no disagreeable odor; it does not, however, possess the germicidal qualities of iodoform. Nosophen, iodol, and airol are among the more recent substitutes. +Iodin.+ This drug no doubt possesses more germicidal properties than was at one time supposed. It is probably the most powerful antipyogenic known. The 7 per cent. tincture is the one most frequently used. +Acetate of Aluminum+, or more properly, aluminium, is prepared by adding five parts of sugar of lead to a solution of five parts of alum in 500 parts of distilled water. Burow’s solution, see page 35, is chiefly employed as a wet dressing. +Chloride of Zinc+ in a solution of 15 to 30 grains to the ounce, has marked antiseptic properties, but it blanches the tissues when applied to infected wounds. +Sulphocarbonate of Zinc+ is less irritating than the chloride of zinc and is of the same value as a germicide. +Peroxide of Hydrogen+ when used as a 15 volume mixture or diluted, seems to have a direct action upon pus generation by destroying microorganisms of the pus. It is frequently employed for sterilizing abscess cavities, and for hastening the separation of necrotic tissue. This agent has also a marked hemostatic power and is used to some extent on this account in nose and throat work. Its hemostatic power is also observed in bone cavities. Care should be taken never to use it unless there is a free exit, as it increases rapidly in volume after coming in contact with dead tissue or pus, and serious accidents have happened from its improper use; for instance, if it is injected into an abdominal sinus where free escape is not provided for, the distention will result in ruptures of the sinus and infiltration of the surrounding tissues; possibly of the peritoneal cavity. The distention produced by it is also quite painful and therefore only a small quantity, or a much diluted solution should be introduced into cavities.