Air Mail cover 1931 (March) Imperial Airways service first flight covers (58), a very fine study of mail addressed to, or originating from the Sudan and carried on various stages of the journey between England and Africa, bearing the adhesives of Sudan (23), Great Britain (18), Egypt (7), Ireland (6), Kenya and Uganda, Belgium, Greece and Tanganyika; included are two Imperial Airways timetables which have been used from Egypt to Mwanza and Khartoum respectively. A fine assembly with various types of cachets, labels and printed envelopes noted