6¢ Orange, 1918 Air Post (C1), vertical pair paying 2¢ postage and 10¢ special delivery fee on December 10, 1918, First Day Cover self-addressed by Joseph B. Leavy, then curator of the National Museum (1913-21), to his residence at 3600 13th Street, N.W., in Washington D.C., stamps tied by “Washington D.C. Dec. 10 8 PM” duplex datestamp with “1918” yeardate and numeral “3” grid cancel--the clerk (or perhaps Leavy) was evidently not satisfied with the clarity of the first strikes, and two more were struck which clearly show the date--in addition, there is a Washington Post Office Special Delivery Department “DEC 10 P.M.” purple time/date handstamp on the back
* Whereabouts unknown until 2007; pencil note on back indicates it was bought in September 1943 for $125
* Found in a collection consigned to Siegel Auction Galleries, 2/19/2007, Sale 950, lot 2424, to William H. Gross
CENSUS, LITERATURE AND EXHIBITION REFERENCES
* Documented by both Joe R. Kirker and Ken Lawrence as the only genuine 6¢ 1918 Air Post cover
* Joe R. Kirker, “The six-cent Jenny of 1918--First Day of Use!!!”, Airpost Journal, February 2009
* Ken Lawrence, “First Day Covers of 1918 Air Post Stamps--or are they? Part 3,” United States Specialist, April 2015
* The Philatelic Foundation (2008)
* Very Fine
* Pencil note on back “9/43 [$]125 Pre First Day C1”
VIEW PDF OF HISTORY AND COMMENTARY at https://siegelauctions.com/2018/1188/105.pdf
VERY FINE. THIS COVER WAS DISCOVERED BY US IN AN OTHERWISE MODEST CONSIGNMENT AND, ACCORDING TO OWNER'S PURCHASE DATE ON BACK, HAS NOT BEEN AVAILABLE TO THE MARKET FOR OVER 60 YEARS. A VERY IMPORTANT UNITED STATES FIRST DAY COVER, OF WHICH THERE ARE FEWER THAN FIVE KNOWN.
Accompanied by an American Philatelist article, "First Day Covers of U.S. 1918 Air Mail Stamps", by Ken Lawrence, which documents five 6c 1918 covers plus an additional three possible First Days.