difficulty, and in most instances in opposition to the traditions of the profession. Such independent effort, though most prominent in the period previous to the year 1800, always has had and always will have a place in medicine. This is seen in the efforts of the individual, even after medicine was influenced by its ancillary sciences and, indeed, in the days of organized laboratory effort. In this connection, one recalls Sir George Baker's demonstration that a form of colic, epidemic in character, occurring in Devonshire, England, was to be explained as a poisoning by lead; Captain Cook's conquest of scurvy; Auenbrugger's invention of the method of percussion; Laennec's invention of the stethoscope; the theory announced independently by Holmes and by Semmelweis of the transmission of puerperal fever and many other independent efforts in the practise of surgery and medicine, as those with which we associate the names of Pinel, McDowell, O'Dwyer and Trudeau.
Modern effort in research in medicine, however, as in science generally, is, it must be admitted, organized laboratory effort, and upon this type of effort present-day progress would seem to depend. Nevertheless, the individual is as important as ever, for "it goes without saying that laboratory buildings alone, even when adequately equipped and with a liberal maintenance budget, are far less important than the men who work in them" (Barker), but the laboratory now offers to the individual, with original conceptions or special talents, advantages, facilities and opportunities which, by aiding and supplementing the work of the individual, render isolated effort unnecessary, time-consuming and often futile.
Under the second head, the influence of physics, chemistry and biology, fall such men as the English physicists and chemists and the French academicians—Boyle, Cavendish, Priestley, Galvani, Faraday, Tyndall, Lavoisier, Gay-Lussac and Berzelius. A more direct influence is seen in the entrance of Pasteur, a chemist, into the field of etiology; of Ehrlich, a physician, but chemically trained, into the field of immunity and specific chemical affinities; and of Metchnikoff, applying the methods of the biologist to the problems of pathology. Likewise Liebig and Wohler and organic chemistry; Hoppe-Seyler and physiological chemistry; Arrhenius and physical chemistry, Darwinism, Mendelism, all have had their influence, and the methods and views they represent have been taken over by medicine and applied to the solution of its problems.
The influence of physics and chemistry in establishing the third factor—organized laboratory effort in special fields of medicine—we have seen in the beginnings of laboratory research in the second quarter of the past century. Virchow at the time he was urging the establish-