National Geographic : 1918 Jan
© Paul Thompson MAKING THE AVIATION CANDIDATE WALK A LITERAL CHALK-LINE With eyes closed, the applicant walks forward and backward. His deviation from the straight and narrow way is one of the determining factors in his acceptance or rejection for service as a pilot of America's great air fleet. )kPaul Thompson PUTTING THE AIRPILOT CANDIDATE THROUGH THE "NYSTAGMUS TEST" With eyes closed, the applicant, seated inarevolving chair, iswhirled around ten times in twentyseconds. The chair isthen stopped and the applicant is told to focus his eyes on adistant object. The visual dis turbance which results from the whirl isknown asthe "nystagmus."