The reciprocal relations of disease and history not only provide food for philosophic speculation but offer much information worthy of study by the statesmen who direct the destiny of nations. The panorama produced by the effect of one on the other has been recently painted by Stewart.1 He questions the historical justification of the relative amount of study devoted, for example, to Napoleon and to Pasteur or to Jenner. Which, he asks, more definitely made and molded history? One cannot question, he concludes, that disease and its gradual control are tremendously important molders of the history of mankind.
The first steps of the nomad in civilization, the gathering of houses into towns, doubtless trebled disease and cost innumerable lives. The principles of sanitation, though known to the ancient Hebrews, for centuries lagged far behind the advance in other lines of what we call civilization. Primitive communities were thus saved