The awakening came in France. In 1801 Bichat, a young man, published a work on general anatomy, in which he placed the seat of disease, not in the organs, but in the tissues or fabrics of which they were composed, which gave an extraordinary impetus to the investigation of pathological changes. Meanwhile, the study of the appearances of organs and bodies when diseased (morbid anatomy), which had been prosecuted with vigor by Morgagni in the eighteenth century, had been carried on actively in Great Britain and on the Continent, and the work of Broussais stimulated a more accurate investigation of local disorders. The discovery by Laennec of the art of auscultation, by which, through changes in the normal sounds within the chest, various diseases of the heart and lungs could be recognized, gave an immense impetus to clinical research. The art of percussion, discovered by Avenbrugger in the eighteenth century, and reintroduced by Corvisart, contributed not a little to the same. Laennec’s contributions to the study of diseases of the lungs, of the heart, and of the abdominal organs really laid the foundation of modern clinical medicine. A little later Bright published his researches on diseases of the kidneys, from which we date our knowledge of this important subject. One of the most complicated problems of the first half of the century related to the differentiation of the fevers. The eruptive fevers, measles, scarlet fever, and small-pox, were easily recognized, and the great group of malarial fevers was well known; but there remained the large class of continued fevers, which had been a source of worry and dispute for many generations. Louis clearly differentiated typhoid fever, and by the work of his American pupils, W. W. Gerhard and Alfred Stillé, of Philadelphia, and George B. Shattuck, of Boston, typhus and typhoid fevers were defined as separate and independent affections. Relapsing fever, yellow fever, dengue, etc., were also distinguished. The work of Graves and Stokes, of Dublin, of Jenner and Budd, in England, of Drake, Dickson, and Flint, in America, supplemented the labors of the French physicians, and by the year 1860 the profession had reached a sure and safe position on the question of the clinical aspects of fevers. The most distinguishing feature of the scientific medicine of the century has been the phenomenal results which have followed _experimental investigations_. While this method of research is not new, since it was introduced by Galen, perfected by Harvey, and carried on by Hunter, it was not until well into the middle of the century that, by the growth of research laboratories, the method exercised a deep influence on progress. The lines of experimental research have sought to determine the functions of the organs in health, the conditions under which perversion of these functions occur in diseases, and the possibility of exercising protective and curative influences on the processes of disease.