The Medical Corps naturally divides itself into two main branches: the Division of Surgery and the Division of Internal Medicine. The latter, as its name indicates, deals almost entirely with non-surgical diseases and conditions; in other words, medicine as distinguished from the knife. One of the principal functions of the Division of Internal Medicine consisted in obtaining, training, if necessary, and assigning to duty in the various hospitals and camps expert examiners in diseases of the heart and lungs, these officers being charged with the duty of determining the fitness of recruits for military service and their condition on discharge, with special reference to heart disease and tuberculosis. This latter phase of their work assumed such important proportions, however, that it was eventually taken over by a separate division. Another function of the division was to obtain mature and highly trained internists of long experience to serve as Chiefs of Medical Service in base and general hospitals, these officers, who included many of the ablest physicians in the United States, being responsible for the professional care of all medical patients. For a time a school was maintained to train these medical chiefs, practically all of whom were fresh from civil practice, in the details of army-hospital administration. Younger men, usually with little or no hospital experience and, therefore, less highly qualified, were assigned to serve under the medical chiefs as ward surgeons in direct charge of sick soldiers. A small number of highly experienced men were also brought into the service as medical consultants, their duties being to visit the various hospitals and to maintain helpful and sympathetic relations between the medical staffs and the surgeon-general in Washington. The above is, of course, merely a hasty sketch of the great work done by the medical internists. The vast majority of them were desperately anxious for service in France and moved heaven and earth to obtain overseas assignments, being bitterly disappointed when they found that the needs of the army required that they should remain on duty in the homeland. By comparison with those of their fellows who were serving within sound and often within range of the guns, domestic service seemed quiet and prosaic. But, as a matter of fact, there was nothing commonplace about it at any time. The nearest approach to it was after the Armistice, when the main impulse and motive for military service, the winning of the war, became a thing of the past. But during the continuance of the war the medical officer, whether his duties kept him on the firing-line itself, in the camp and base hospitals in the rear, far from the thunder of the cannon, or at the cantonments on this side of the Atlantic, never had reason to complain of his work being monotonous or uninteresting, for every day, almost every hour, indeed, brought new experiences and new problems.