Air Mail cover 1924 (Mar.) Sqn. Ldr. Maclaren attemped Round the World flight, envelope to Huddersfield marked "Carried by Air Worlds Flight" and "Registered", bearing G.B. 1½d. (3) cancelled by Indian T.P.O c.d.s. for 9 May, signed by Flight Officer Plenderlith and complete with letter signed by him explaining there being "stuck in the middle of the sand desert waiting a new engine"; most unusual