important acting from within has been the use of animals. The study of the great domain of infectious diseases has revealed such a similarity between the diseases of man and the higher animals that we hesitate now less than before to apply courageously the knowledge gained in our experiments upon the highest mammals to human physiology and pathology. Without this aid from animal life, medicine as a progressive experimental science would dwindle into insignificance. Moreover, the artificiality, the rigidity and awkwardness of the medicine of a generation ago have been largely dissipated by its contact with biology, which brought with it the comparative point of view.
Side by side with the use of animals we may place the convenient use of bacteria and other microorganisms in our laboratories in producing disease as one of the great levers of pathological research today. They have enabled the investigator to establish important centers of research completely independent of and coordinate with those connected with the hospital and the dead-house. The latter, it is true, still remains a final court of appeal for all discoveries destined for the relief and cure of human diseases.
In the historical development of science the research instinct appeared at first sporadically, and until recently it was simply the spontaneous flowering of the scholarly mind in the highest institutions of learning. To-day it has been actually organized not so much to train youth as to produce useful knowledge. This new organization of research has been greatly favored by the promise of valuable returns in the suppression of infectious diseases of man and animals. Most of the institutions founded thus far were created by public authority for this purpose. It was realized that such work must be pushed forward rapidly to secure results of value to public health and economy.
About twenty-five years ago special laboratories began to appear. Our own government figured among the earliest in voting what were then very liberal appropriations for the study of infectious animal diseases. At the same time came the German Imperial Health Office and somewhat later the Institute for Infectious Diseases in Berlin, and the Pasteur Institute in Paris; more recently there have been established the Institute for Experimental Therapy in Frankfort, Germany, and the many sero-therapeutic institutes and public health laboratories, nearly all of which have become noted for their research work. In our own country we have last but not least the Rockefeller Institute for Medical Research of this city and the Memorial Institute for Infectious Diseases in Chicago. Most of these were created to deal scientifically with problems of immediately practical bearing. But it does not need a prophet to foresee that following them others will arise which will devote themselves to broader and more fundamental problems and which will attack those left unsolved by the former institu-
