Emphysema is formed by a flatulent spirit, collected sometimes under the skin, sometimes under the periosteum, or the membranes which surround the muscles. And it is also sometimes collected in the stomach and intestines, or between them and the peritoneum, in those kinds of dropsy which are called tympanitic; and it differs from œdema in this, that the parts do not pit upon pressure like it, and that it sounds like a drum. The density of the body co-operates in preventing the flatus from being dissipated, at the same time that the flatus also is of a thick nature. Wherefore, the indication of cure is to rarefy the body, and attenuate the thick air; which is to be accomplished by means of attenuant and heating remedies. When the complaint is seated in the stomach and intestines, this is to be brought about by a fine oil, having rue, cumin, or parsley seed boiled in it. And sometimes a large cupping instrument without scarificators, applied two or three times to the navel, will discuss it. When the muscles from contusion are inflated, so as to sound like an emphysema, the parts will not bear very heating and acrid applications. Wherefore, at the commencement, we must use paregorics liberally, and, when the disease is on the decline, discutients. Thus we may use sodden must with a small quantity of oil, applying them warm upon unwashed wool, or mixing the cerate of unwashed wool. And we must take care that the heat be preserved, for it is not expedient that the part be cooled. When the patient has been soothed, we are to mix vinegar and nitre or aphronitrum, and afterwards some lye; and lastly, we may use discutient plasters, for the removal of the complaint such as the following: having boiled the sordes of the oil used in baths, strain it first, so that it may become pure, and again throw it into the pot, and having triturated slaked lime like flour, sprinkle until it become of the consistence of clay, and use. A still more effectual application is the compound medicine from sycomores. * * * * * COMMENTARY. See Galen (Meth. Med. xiv); (Therap. ad Glauc. ii); Aëtius (xv, 2); Oribasius (Synop. vii); Actuarius (Meth. Med. ii, 12); Nonnus (252); Scribonius Largus (§ 119); Avicenna (iv, 3, 2, 20); Serapion (v, 23); Alsaharavius (Pract. xxix, § 1, 14); Rhases (Divis. 127, Cont. xxvii.)