A commemorative envelope or cover celebrating National Air Mail Week, May 15 to 21, 1938. The cachet features a plane flying over the Susquehanna River, White Island, and Herndon, Northumberland County, Pennsylvania. The machine cancel was applied at Herndon, May 16, 1938, at 12:30 P. M.
This cover and design were approved by J. Paul Garrett, Postmaster of Herndon, and his signature appears at lower left.
The early history of air mail in the United States is well-documented through covers of this type which were widely collected throughout the United States. This particular cover was sent to Port Carbon, Pennsylvania.
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