ounces of the oily solution were poured daily over the towel for the first week, after which the dressings were left untouched for three days and then entirely removed. The wound was found quite dry, and free from tenderness. When the animal was subsequently killed, the ligatures were seen to be converted into living tissue; and such experiments proved how valuable animal fibres might be as ligatures under the antiseptic system. Again, a portion of cotton wool was impregnated with about one two-hundredth part of its weight of carbolic-acid vapour, and the surface of a granulating sore and surrounding skin was washed with a dilute solution of the acid. A piece of oiled silk of the size of the sore was then applied, to prevent the dressings from sticking through becoming dry. Over this was placed a piece of folded linen rag of rather larger size, and similarly impregnated with carbolic acid vapour to the cotton wool; this being intended to absorb any discharge from the sore. Lastly, an overlapping mass of carbolised cotton wool was securely fixed over all. The result was that although all chemical antiseptic virtue left the dressing by evaporation of the volatile carbolic acid in a day or two, yet putrefaction was practically excluded by the cotton wool for any length of time. Subsequently another variety of protective material was adopted, namely antiseptic gauze, a loose cotton fabric, the fibres of which were impregnated with carbolic acid lodged in insoluble resin. The interstices between the fibres were kept free from these ingredients, so that the porous fabric might readily absorb discharges. By arranging this in a sufficient number of layers and covering the whole with a layer of mackintosh, the discharge was compelled to pass through the whole length of the antiseptic dressing. Thus it was almost certain that if no putrefactive mischief were left in a wound or abscess, none would enter it, however profuse might be the discharge. If a wound was presented for treatment, inflicted by some other than the surgeon, some dust was sure to have been introduced, which probably contained putrefactive germs. The energy of these had first to be destroyed by washing the raw surface with some strong antiseptic agent. But in operating upon a previously unbroken skin, Mr. Lister considered that he could prevent the septic particles from entering at all, by operating in an antiseptic atmosphere. This was provided by producing a shower of spray of carbolic acid of the finest character. This answered exceedingly well when the solution producing the spray consisted only of one part of carbolic acid to 100 parts of water.