The Arabians mention a variety of applications for producing the rupture of abscesses. (See in particular Avicenna and Rhases.) Thus, they recommend a plaster consisting of cantharides and old oil. Some of their applications contain nitre, quicklime, and arsenic. Such a composition, by producing a slough, would no doubt effect the purpose for which it was intended. Haly Abbas recommends a poultice made of leaven, boiled figs, and the seeds of rosemary. He speaks of onions as an application to indolent abscesses. Alsaharavius treats of abscesses at great length. By abscesses of the nervous parts it will be readily understood that our author does not mean that they are seated in what are now properly called nerves, but in tendinous and membranous parts, for all these were comprehended under the name of nerves by the older writers, namely, Hippocrates, Plato, and Aristotle. Galen pointed out clearly the distinction between these parts, but the term is often used in its old and popular acceptation by the writers subsequent to him. The account which our author gives of deep-seated abscesses is highly interesting, but is mostly borrowed from Galen (ad Glauc. ii.) Rhases, in his ‘Continens’ (xxvii), gives an interesting outline of the opinions of all preceding authorities, with some ingenious observations of his own. When there is any hope of producing resolution he approves of scarifications. When the pain is violent he recommends hot and humid applications with the addition of narcotics. After the abscess has been opened with the knife, he says that desiccative applications are indicated, and not ointments containing wax or oil. He describes the leaven cataplasm, and others of a similar nature. He gives Antyllus’ directions for opening abscesses. Abscesses in the limbs are to be opened by a straight incision, but those about the ancles by a circular, as they are apt to terminate in fistulæ. He recommends it to be made at the lower part of the abscess, but mentions that Galen prefers the thinnest part. SECT. XIX.—ON GANGRENE AND SPHACELUS.