Air mail. Foreign air mail service, hearing, 75th Congress, 1st session, on S. 2516, providing for transportation of mails on certain commercially operated aircraft, S. 2550, to permit printing of black-and-white illustrations of United States and foreign postage stamps for philatelic purposes, and S. 2584, to dispense with necessity for insurance by Government against loss or damage to valuables in shipment, June 16, 1937.