GREAT BRITAIN → SOUTH AFRICA Imperial Airways airmail cover to Cape Town with London 8 Dec 1931 datestamp carried on the inaugural Christmas flight of the “Heracles” between London and Cape Town.  Letter was part of the main mail despatched to Paris by an earlier liner.  On back Johannesburg 21 Dec 1931, Cape Town POSTE RESTANTE 22 Dec 1931 and Cape Town datestamps.