Lanfranc the great French surgeon's description of the treatment of the bite of a rabid dog is interesting. He suggests that a large cupping-glass should be applied over the wound, so as to draw out as much blood as possible. After this the wound should be dilated and thoroughly cauterized to its depths with a hot iron. It should then be covered with various substances that were supposed "to draw," in order as far as possible to remove the poison. His description of how one may recognize a rabid animal is rather striking in the light of our present knowledge, for he seems to have realized that the main diagnostic element is a change in the disposition of the animal, but above all a definite tendency to lack playfulness. Lanfranc had manifestly seen a number of cases of true rabies, and describes and suggests treatment for them, though evidently without very much confidence in the success of the treatment. The treatment of snake-bites and the bites of other animals supposed to be poisonous, or at least suspicious, followed the principles laid down for handling the bite of a mad dog. This was the case particularly as to the encouragement of free bleeding and the use of the cautery. A characteristic example of the power of clinical observation of the medieval physicians, and one which illustrates much better than many of the absurd tales told as typical of their superstitious tendencies, but really representing that tendency always present in mankind to believe wonders, is to be found in how much they learned of rabies. Even in our own time there are many absurd beliefs with regard to this disease, with some denials of its existence and many grossly exaggerated tales, widely believed; yet the medieval people seem to have reached some quite rational notions with regard to it. Bartholomæus Anglicus is the author of a popular encyclopedia which was very widely read in the medieval period. He was an English Franciscan of the thirteenth century, who gathered together a lot of information and wrote a volume that for centuries after his time, even down to Shakespeare's boyhood, was popular in England. Here is his description of rabies as he knew it. The most important element is his recognition of the uncertainty of the length of the incubation period, but it contains two other ideas that are very interesting, because medicine in subsequent centuries has come back to them over and over again. One is that free bleeding may remove the virus, and the other that the cautery may help in preventing the infection.