1. Antiseptics prevent putrefaction in a wound by virtue of their action in arresting the growth of organisms, or destroying these or the chemical activity of certain substances which give rise to fermentation and decomposition. They include: Carbolic Acid, Creasote, Boracic Acid, Iodoform, Iodine, Eucalyptus, Thymol, Salicylic Acid, Quinia, Sulphurous Acid, Perchloride of Mercury, Chloride of Zinc, Alcohol, Permanganate of Potash, Turpentine, Benzoin, Balsam of Tolu, and Balsam of Peru.

2. Disinfectants are substances which destroy microorganisms, or active chemical substances and their products, on surfaces already foul or infected. They are for the most part the same materials as the antiseptics, but are employed in a much stronger form. Such are strong solutions of Chloride of Zinc and Carbolic Acid, Iodoform, Iodine, Sulphurous Acid.

3. Deodorants absorb gases and neutralise foul odours. Those chiefly used are Charcoal, Permanganate of Potash, and Iodoform.

4. Astringents coagulate or precipitate the albuminous discharges, coagulate the germinal protoplasm of the upper layers of cells, and either directly contract or indirectly con-stringe the vessels, so as to limit exudation. They are used to check excessive discharge and granulation growth; and thus give tone to wounds. Astringents include: Solutions of Nitrate of Silver, Subacetate and Acetate of Lead, Sulphate of Zinc, Sulphate of Copper, Alum, Persalts of Iron, Tannic Acid and its allies, and Carbolic Acid.

5. Stimulants are for the most part mild astringents, applied chiefly in the form of lotion; such as weak solutions of Nitrate of Silver, Sulphate of Copper, Sulphate of Zinc, Carbolic Acid, etc. They are more efficacious as weak spirituous solutions. Stimulants are used to wounds when healing flags or the granulations tend to become prominent.

6. Styptics are applied to wounds to check haemorrhage. They include: Ice, Persalts of Iron, Nitrate of Silver, Matico, Tannic acid.

7. Caustics and Escharotics are intended to destroy part of the living tissues, and thus destroy or arrest the activity of organic poisons, as in bites, dissection wounds, syphilis, malignant disease. and gangrenous processes. They include: Caustic Alkalies, Mineral Acids, Solution of Chloride of Antimony, Chloride of Zinc, Nitrate of Silver, Sulphate of Copper, Arsenic, Acid Nitrate of Mercury, and Dried Alum.

8. Vesicants are applied to chronic ulcerating surfaces to stimulate the circulation in the surrounding parts, and soften callous edges. Cantharides is chiefly used.

9. Anodynes are intended to alleviate the pain of wounds and ulcers, and induce sleep. The medicinal anodynes commonly thus applied are preparations of Opium and Belladonna.