One might well expect that, with trephining as frequent as this textbook of the Four Masters more than hints, the death-rate of these medieval surgeons must have been very high in head cases. We can scarcely understand such intervention in the conditions of operation assumed to exist in the Middle Ages without almost inevitable infection and consequent death. They seem to have come to an empiric recognition of the advantage of absolute cleanliness in such operations. Indeed, in the light of our modern asepsis and its development during our own generation, it is rather startling to note the anticipation of what is most recent in the directions that are given to a surgeon to be observed on the day when he is to do a trephining. I give it in the original Latin as it may be found in Gurlt (vol. i., p. 707): "_Et nota quod die illa cavendum est medico a coitu et malis cibis æra corrumpentibus, ut sunt allia, cepe, et hujusmodi, et colloquio mulieris menstruosæ, et manus ejus debent esse mundæ_, etc." The directions are most interesting. The surgeon's hands must be clean; he must avoid coitus and the taking of food that may corrupt the air, such as onions, leeks, and the like; must avoid menstruating women; and in general must keep himself in a state of absolute cleanliness. After the South Italian surgeons, some of whom taught at Bologna, a group of North Italian surgeons, most of whom probably were either direct or indirect pupils of the Salernitan School, must be considered. This includes such distinguished names in the history of surgery as Bruno da Longoburgo, usually called simply Bruno; Theodoric and his father Hugh of Lucca; William of Salicet; Lanfranc, the disciple of William who taught at Paris, and gave that primacy to French surgery which was maintained all the centuries down to the nineteenth (p. 1); and Mondino, the author of the first manual on dissection, which continued for two centuries to be used by practically everyone who anywhere did dissection throughout Europe. Practically all of these men did their best work between 1250 and 1300. Bruno of Longoburgo taught at Padua and Vicenza, and his textbook, the "Chirurgia Magna," was completed in Padua in January, 1252. Gurlt notes that "He is the first of the Italian surgeons who besides the Greeks quotes also the Arabian writers on surgery." Eclecticism had definitely come into vogue to replace exclusive devotion to the Greek authors, and men were taking what was good wherever they found it.