knowledge may appear to us moderns, there are good reasons for believing that hundreds of years must have elapsed before the accumulated stock of such experiences became really considerable. On the other hand, it is reasonable to suppose that this growth in medical knowledge took place more rapidly in certain tribes or races than in others, and that when, under the action of wars, the inferior men became tributary to those of greater intellectual powers, they acquired, through contact with their conquerors, additional knowledge at a much more rapid rate. One great hindrance, however, stood in the way of such progress. I refer to the deeply rooted belief, entertained by man in this primitive period of his existence, in the agency of malevolent spirits (demons) in the production of disease,—a belief which continued to exist for many thousands of years. Out of such a belief developed the necessity of discovering some practical method of appeasing the evil spirits and of thus obtaining the desired cure of the ills of the body. Usually some member of the tribe who had displayed special skill in the treatment of disease, and who at the same time was liberally endowed with the qualities which characterize the charlatan, was chosen to be the priest or "medicine man." It was his duty to employ measures suitable for expelling the demon from the patient's body and for restoring the latter to health. Possessing great influence, as these superstitious people believed he did, with the unseen gods, such a physician-priest must have discouraged all efforts to increase the stock of genuine medical knowledge; for such an increase would necessarily mean a diminution of his own power and influence.
In what must still be termed the age of primitive medicine, but undoubtedly at an advanced stage of that epoch, there were performed surgical operations which imply a remarkable advance in the invention of cutting instruments and in the knowledge of the location and nature of certain comparatively rare diseases, and at the same time great courage and wonderful enterprise on the part of those early physicians. As evidence of the correctness of these
