"This 1941 manual sets forth the nature, types, and purposes of aerial photography with its application to military requirements. The Air Corps functions with respect to aerial photography and the factors affecting the execution of these function...
United States Antiaircraft Artillery School (Camp Davis, N.C.)
"The purpose of this publication is to outline methods of land navigation and artillery orientation that will be applicable in any hemisphere, that will permit the determination of direction with more precision than may be expected by means of a...
"The purpose of this 1941 manual is to present in simplified form necessary information for instruction of all military personnel in elementary map and aerial photograph reading."