The nineteenth century was one of epoch-mak ing discoveries, only a few of which van even he mentioned within the limits of this arti de. In the early years of the century Laennee (q.v.) invented the stethoscope and thereby in stituted a complete revolution in the methods of physieal diagnosis; Virchow (q.v.) founded mod ern cellular pathology: Pasteur (q."•)• by his studies in fermentation and putrefaetion.prepared the way for the germ theory of disease: and Lister (q.v.), stimulated by Pasteur's discoveries, gave to surgery the antiseptic treatment of wounds. Laveran (q.v.) in 1880 discovered the plasmodium of malaria (q.v.), and Koch (q.v.) in 1882 the bacillus of tuberculosis. Sine(' then it has been proved that anthrax. Asiatic cholera. and most of what are called the specific infec tious diseases are due to minute vegetable organ isms. (See IlAcTEnt.t.) The discovery of general anesthetics was no less important and remark ahle. Morton (Tv.). of Boston, demonstrated the anesthetic properties of sulphuric ether in 18411; and Simpson. of Edinburgh, introduced chloro form in 1817. The introduction of eneaIne as n
lo(al inuesthetie in 1884 by Koller made possible the performance of painless operations on the eye and in the nose and throat and other parts of the body. The materia medics has been enriched by the addition of quinine. morphia, stryehnine, iodine and the iodides, the bromides. hydroeyanie avid, and cod liver oil. and. more interesting than the.e, of antitoxic• Svc .\NTuroxr': SERPA! THERAPY.) Diphtheria espc. eially has saved thousands of live,. -\ thong the more important instraments invented during Ilie nineteenth cenlury are the ophthalmoscope and the hryng..eupe. The X-rays (q.v.) and th • Finset' rays (see I'uo•ro'rnEearv) are of too recent napalm-thin to have proved their worth. For a complete review of the medical progress of the nineteenth century. consult the fah rnrr• lingo/ Book for 1900, Consult : Baas. 1/is• !or// of 1/ rdici lo• (Now York, 18991 : Park. Is of the Ills/ore of Ilrflicine (New York. P499) : and Bennet. Diseases of thr Bible (Lon don. 1S41 ) •