MIL-C-228A, MILITARY SPECIFICATION: CIRCLES, AZIMUTH; AND CIRCLES, BEARING (21 NOV 1952) [NO S/S DOCUMENT]

MIL-C-228A, MILITARY SPECIFICATION: CIRCLES, AZIMUTH; AND CIRCLES, BEARING (21 NOV 1952) [NO S/S DOCUMENT]., This specification covers azimuth and bearing circles for use in the accurate determination, of the bearings of terrestrial objects and the azimuths of celestial bodies.