envelope to England showing "POSTAL SERVICE M.E.F./AERIAL POST-BAGHDAD-DELHI/PER/HADLEY-PAGE AEROPLANE" cachet in magenta cancelled by F.P.O. 55 c.d.s. at left, the reverse showing circular "CARRIED BY AERIAL MAIL/BAGHDAD-DELHI/JANY. 1919" cachet in violet and Delhi 20 January c.d.s. Photo" /> Air Mail cover 1919 (9 Jan.)<I> "On Field Service"</I> envelope to England showing "POSTAL SERVICE M.E.F./AERIAL POST-BAGHDAD-DELHI/PER/HADLEY-PAGE AEROPLANE" cachet in magenta cancelled by F.P.O. 55 c.d.s. at left, the reverse showing circular "CARRIED BY AERIAL MAIL/BAGHDAD-DELHI/JANY. 1919" cachet in violet and Delhi 20 January c.d.s. Photo | Christie's