conscience. They are content to rest in the uncertain position which satisfied Dr. Abercrombie, the distinguished author of the well-known "Inquiry concerning the Intellectual Powers," who, having pointed out plainly the dependence of mental function on organization, and, as a matter of fact which can not be denied, that there are individuals in whom every correct feeling in regard to moral relations is obliterated, while the judgment is unimpaired in all other relations, stops there without attempting to prosecute inquiry into the cause of the remarkable fact which he justly emphasizes. "That this power," he says, "should so completely lose its sway, while reason remains unimpaired, is a point in the moral constitution of man which it does not belong to the physician to investigate. The fact is unquestionable; the solution is to be sought in the records of eternal truth." And with this lame and somewhat melancholy conclusion he leaves his readers impotent before a problem which is not only of deep scientific interest, but of momentous practical importance. The observation which makes plain the fact does not, however, leave us entirely without information concerning the cause of it, when we pursue it faithfully, since, it reveals as distinct a dependence of moral faculty upon organization as of any other faculty.
Many instructive examples of the pervading mental effects of physical injury of the brain might be quoted, but two or three, recently recorded, will suffice. An American medical man was called one day to see a youth, aged eighteen, who had been struck down insensible by the kick of a horse. There was a depressed fracture of the skull a little above the left temple. The skull was trephined, and the loose fragments of bone that pressed upon the brain were removed, whereupon the patient came to his senses. The doctor thought it a good opportunity to make an experiment, as there was a hole in the skull through which he could easily make pressure upon the brain. He asked the boy a question, and before there was time to answer it he pressed firmly with his finger upon the exposed brain. As long as the pressure was kept up the boy was mute, but the instant it was removed he made a reply, never suspecting that he had not answered at once. The experiment was repeated several times with precisely the same result, the boy's thoughts being stopped and started again on each occasion as easily and certainly as the engineer stops and starts his locomotive.
On another occasion the same doctor was called to see a groom who had been kicked on the head by a mare called Dolly, and whom he found quite insensible. There was a fracture of the skull, with depression of bone at the upper part of the forehead. As soon as the portion of bone which was pressing upon the brain was removed the patient called out with great energy, "Whoa, Dolly!" and then stared about him in blank amazement, asking: "Where is the mare? Where am I?" Three hours had passed since the accident, during
