Air Mail 1931 Pigeongram envelope with missive carried from Hazaribagh to Calcutta, 1933-77 pigeon post missives (5) and 1941 printed pigeon post envelopes (2) containing advertising brochures from Kalyan to Bombay with "SERVICE" 1a. 3p. cancelled by special d.s.; also 1938-83 Balloon Mail envelopes (13) and card