With the great development of aviation during the late war, it became necessary for the advancement of aviation as a military measure and for the safety of those engaged in it, to study the physical requirements for successful flying and for the performance of the various military duties required. This demanded a thorough study of the physiologic response to altitude. To accomplish this the government maintained a research laboratory in which a large amount of work was done on the physiologic response to altitude, visual requirements for flying, the mechanism of equilibration, the psychologic reactions under different conditions, reaction time and the various bodily requirements. In addition, the experiences in the flying fields in this country and abroad and in the combat zone were collected and analyzed.
In the course of such investigations, it was inevitable that important contributions should be made to our fundamental knowledge. All of this material