1929 (23 May) Panama City to Guayaquil, Ecuador FFC, 2c entire with add’l 10c postage and two varieties of the “Correo Aereo” ovpt, one DOUBLE, the other INVERTED (Scott C2a-b; 300 each existed), all tied by May 23 duplex ds, boxed flight cachet, sent reg’d with May 25 bs, very fine (Image)

1918 (Oct. 18) “First Non-Stop Ocean to Ocean Aero Mail Service,” long Official “Liberty Loan” cover flown Cristobal-Balboa Heights with both cachet-cds, only a few now known, very fine (central fold) (Mü. 1, 25’000pts) (Image)

1920 (Oct. 6) First Air Service Dispatch cover with special cachet ds of Cristobal and 2c ovpt. tied at Balboa (Oct. 4), special boxed 6-line cachet “Aviator Encountered Impossible Weather Conditions Nearing Jamaica, Compelling Return. Mail Re-dispatched by Steamer,” addressed to John Luff of Scott’s, truly scarce, very fine (Mü. 2, 10’000pts) (Image)

1925 (2 Jan.) FFC for trial flight, Cristobal, Canal Zone to Costa Rica, long cover with plate n° vert. strip of 5 of 1c Deep Green (Scott 71) all tied by special cds, blue San Jose airmail receiver at BL, no top backflap, fine (Mü. 4, 2’500pts) (Image)