The British, French and Italian Governments detailed to this country, upon our appeal, a few expert fliers and teachers of flying to aid in the early development of our effort and cadets were sent from the United States to the flying fields of Canada, England, France and Italy to hasten their training. Some of these joined the flying forces of those countries and others returned after a few months to become instructors at our own hastily established fields. The few civilians and army men who had learned flying in pre-war days were at once set to work as instructors at the primary fields. The most apt of the American cadets, of whom many took to flying as do birds of the air and quickly became expert, were used as instructors at the home fields instead of being sent overseas for service. And so finally an expert and capable instruction personnel was built up and a system of instruction evolved that represents a work of such diligence, ingenuity, resource and enthusiastic and incessant effort as to make it one of the many memorable achievements of the war. At the beginning of the evolution of the training system it was necessary to organize medical boards to pronounce upon the physical fitness of candidates. The requirements were rigid and the work was new and therefore the highest available medical skill must be obtained. Fifty or more of these boards were established and in the first year examined nearly 40,000 men, of whom almost half were unable to pass the severe tests. As the months went on, experience developed the methods of determining the applicant’s physical fitness for flying to a remarkable degree of efficiency. The American system of training diverged somewhat, at its very beginning, from that of other nations, since it demanded a higher degree of scholastic attainment, a collegiate degree or a certain amount of collegiate work being a requisite, as it was believed that the mental development thus obtained would enable the student flier to advance more rapidly. As the system was finally developed, the candidate who had passed successfully the initial physical test had first a month of military training at a camp devoted solely to this work to give him due regard for discipline and for accuracy of statement in the making of reports, to inspire him with military morale and to give to his body and spirit a thorough testing in order that those who should fall short under its severe demands might be sifted out at the beginning. [Illustration: AIRPLANE AMBULANCE] [Illustration: AMERICAN FLYING FIELD IN FRANCE]