Until 1884 it was excessively difficult to locate with any degree of accuracy a tumor within the brain, but in that year Dr. Bennett, of London, for the first time accurately located a tumor within the skull without there being the slightest evidence on the exterior of its existence, much less of its location. Mr. Godlee (surgeons in England are not called “Dr.,” but “Mr.”) trephined the skull at the point indicated, found the tumor, and removed it. True, this patient died, but the possibility of accurately locating a tumor of the brain, reaching it and removing it, was now demonstrated, which is far more important to humanity at large than whether this individual patient survived or not. Since then there have been a very large number of tumors successfully removed. The latest statistics are those of Von Bergmann, of Berlin, in 1898. He collected 273 operations for brain tumors, of which 169 (61.9 per cent.) recovered, and 104 (38.1 per cent.) died. This is by far the best percentage of results so far reported, but there is reason to believe that with the constant improvement in our ability to locate such tumors and in our methods of removing them, the mortality rate will be still further lessened. Even more successful than the surgery of brain tumors has been the surgery of abscess of the brain. I have no available statistics of the exact numbers, but it is certain that several hundred have been operated on, and with even better success than in the case of brain tumors. The most frequent cause for such abscesses is old and neglected disease of the ear. No child suffering from a “running from the ear,” which is especially apt to follow scarlet fever and other similar disorders, should be allowed to pass from under the most skilled treatment until a cure is effected. This is the commonest cause of abscess of the brain. The inflammation in the ear, which begins in the soft lining of the cavities of the ear, finally extends to the bone, and after years of intermittent discharge, will suddenly develop an abscess of the brain, which, if not relieved, will certainly be fatal. Prompt surgical interference alone can save life, and, happily, though we cannot promise recovery in all, a very large percentage of success is assured. In epilepsy, as a result of injuries of the head, in a moderate number of cases, we can obtain a cure of the disease by operation, but in the great majority of cases, and, one may say, practically in all of the cases in which the epilepsy originates “of itself,” that is to say, without any known cause, it is useless to operate, certainly at least after the epileptic habit has been formed. Possibly were operation done at the very beginning we might obtain better results than experience thus far has shown us is possible.