The examination of the aviators for the Air Service of the United States is much more strict than that of any other nation. In spite of the careful examination that eliminates men with manifestly imperfect eyes, fliers sometimes exhibit marked derangement of the ocular functions under the stress of flying and the conditions connected with it.
In all articles pertaining to the selection of aviators, from the Allies or from alien countries, normal vision is considered to be the chief requisite. Surgeon H. Graeme Anderson of the Royal Naval Service and adviser to the British Air Medical Service, in a discussion of the physical qualifications of fliers, says, "Practically every one of the physicians and officers taking part in the discussion agreed that the function of vision was of the greatest importance."
With this in mind, visual acuity under oxygen depletion, as compared with the behavior of this function under