When the inflammation is neither resolved nor converted into pus, it often passes into gangrene and sphacelus, of which we shall now treat. Wherefore, we give the name of gangrene to mortifications arising from the violence of the inflammation, when they are not yet formed but forming; and if such a state is not speedily cured, the affected part readily dies, and the disease seizing upon the surrounding parts, kills the person. But when the parts thus affected become totally insensible, the affection is no longer called gangrene, but sphacelus. This affection happens also to the bones when the flesh that surrounds them engendering noxious humours impregnates the bones therewith, and causes them to putrefy. When, therefore, the part is completely mortified, it must be speedily cut away, where it joins the sound part. Gangrene is to be cured by evacuating as much as possible of the blood in the affected part; and we may either procure the discharge of the corrupted blood by opening a vein, when the vein of the part is large, or we may divide the whole skin by many and deep incisions, so that the blood may be permitted to escape; and we may apply some of the medicines suitable to mortifications. These are, the flour of tares, or of darnels, or of beans with oxymel. When wishing to apply stronger ones we may add salts, or use the trochisk of Andron, or the like. Old walnuts are good applications for gangrene. The nettle also cleans them, and the juice of spurge, when applied in season and in proper quantity. The decoction of bitter lupines, poured on the part, is also beneficial. Some after the incision, for the sake of security, apply the cautery, in which cases we must use salt with leeks: afterwards, in order to remove the eschar, we may apply a cataplasm of bread, or of barley, or of wheaten flour boiled in water and oil; or the dry cephalic powder with honey, and the tetrapharmacon; and that called the Macedonian may be used. The eschars may be properly removed by bread triturated with parsley, or basil, or by iris, panacea, or birthwort, or by the sweet-flag with honey, or by frankincense. And the medicine of Machærion takes away the eschars in a proper manner, and the iris spread upon pledgets with honey; but in soft bodies the flour of tares, with honey, is sufficient. _From the works of Oribasius, for gangrene._ Of scraped verdigris, of vermilion, of stone alum, equal parts; triturate in water and anoint. The flour of darnel, with radish and salts, and sometimes with vinegar, will, when applied as a cataplasm, be proper for the scarified parts; also dried grapes deprived of their stones with the bark, and with salts and oxymel; the inner parts of walnuts, and myrtle leaves boiled in wine and triturated with honey. Radish, with vinegar, breaks the eschars even to the bone. * * * * * COMMENTARY. See the authors referred to in the 17th Section.