BYRD’S NORTH POLAR EXPEDITION.
CHICAGO EXPOSITION (1933–1934)
COMMUNIST CHINESE REVOLUTION.
CORONATION OF QUEEN ELIZABETH.
COURTMARTIAL OF BILLY MITCHELL.
DELANO GRAPE STRIKE.
DEMOCRATIC CONVENTION, CHICAGO, 1968.
EARLY FRENCH AVIATION (1901–1913)
EXPERIMENTAL AIRCRAFT: HELICOPTERS.
EXPERIMENTAL AIRCRAFT: ORNITHOPTERS.