A gangrene and mortification is only to be dreaded, when a whole limb is inflamed, such as an arm, a leg, &c. When the inflammation is dreadful, that the blood can find no passage at all, but is obstructed on all sides, then the part must naturally die, and become cadaverous. The cause of this misfortune may be either a heavy contusion, a compound fracture, a gun-shot wound, or an internal malignity of the bone itself; and as a caution, I must also add, that pricking a tendon in bleeding may occasion this dreadful malady. There is another kind of mortification which proceeds from a bad habit of body, a poorness of constitution, or when the whole mass of blood is corrupted by the scurvy. This shall be taken notice of in its proper place. ------------------------------------------- SECT. II. _Of Ulcerations_ This is a part of surgery that many pretend to, but what very few really understand. There are however laws in the animal œconomy, which when they are violated, leads us to trace its many evil consequences. An ulcer is a dissolution of solids, occasioned by acrimonious humours, which not only act spontaneously upon each other, but prevent the remaining circulating part from the formation of unnatural substances. Exulceration, strictly speaking, is what every part of the animal fabric is subject to; from the external surface, to the very substance of the bone itself. In this sense, every eruption, as well as the carius of the bones come under that denomination; but more particularly, the corruption of the softer parts on the surface of our body, is here the subject. I shall not enter into a detail of the many kinds of ulcers generally enumerated; they have all in common an corruptive acrimony, and a depraved accretion of excressence in their nature; which differ only, according to the parts ulcerated, and the habit of body; and I have ever found in my practice, that one proper method serves for all; I shall therefore in a simple manner give such directions as will ever be attended with success. The principal intention is to correct the malignity of the humour peculiar to ulcers; to bring them into a good suppuration, and nature, all kind NATURE! will perform the rest. When an ulcer is inflamed all round, filled up with fungous substance, of various colours, the matter thin, ferous, and is very fœtid; then first wash the sore gently with some good soap suds, or let the part ulcerated be steeped in it for some little time, which will draw out the malignity; then apply the following dressing: