Perhaps the most striking argument in favor of the experimental attitude of Dante's century is that afforded by certain facts in the history of medicine of that epoch. Then surgery began to make vast strides. Pagel, regarded in our time as the best informed writer on the history of medicine, has this to say of the surgery in Dante's age. "The stream of literary works on surgery flows richer during this period. While surgeons are far from being able to emancipate themselves from the ruling pathological theories, there is no doubt that in one department, that of manual technics, free observation came to occupy the first place in the effort for scientific progress. Investigation is less hampered and concerns itself with practical things and not with artificial theories. Experimental observation was in this not repressed by an unfortunate and iron-bound appeal to reasoning." (The Popes and Science, p. 172.) As to medical practice in the thirteenth century, interesting data are furnished by the Bulletin of Johns Hopkins Hospital and the Journal of the American Medical Association, January, 1908. The former publication gives us remarkable instances of surgical operations and of the treatment of Bright's disease, matters which we might have thought possible only in the nineteenth century; the latter publishes in full the law for the regulation of the practice of medicine issued by Emperor Frederick II in 1240 or 1241. According to that law binding on the two Sicilies, three years of preparatory university work were required before the student could begin the study of medicine. Then he had to devote three years to the study of medicine and finally he had to spend a year under a physician's direction before a license was issued to him. In connection with this high standard of a medical education, the law of Frederick II forbade not only the sale of impure drugs under penalty of confiscation of goods, but also the preparation of them under penalty of death--stern legislation, anticipating by nearly seven centuries the American Pure Drug Law. (The Popes and Science, p. 419.)