Hello, I have 3 very old (1928) airmail 'notices' from the USPO., All in very good condition for their age. They are all around 5 3/4 inches by 3 inches:
(1) Thin paper blue ink, announces airmail has been reduced to 5 cents for the first ounce. It has plenty of info on both sides and has a postmaster signature printed on it: J.J. Kiely.
(2) On heavier stock, red and blue ink printed on one side "To the Public" announcement from same postmaster. This one has New York, N.Y. on it.
(3) Similar to above but has image of airplane and is mostly artwork. But the back of it has a hand stamped postmark: March 15, 1928. Inside the circular postmark is: CHARLES WINCHELL NEW YORK CITY P.O. Box 937 City Hall Sta.
These have to be extremely rare. Does anyone know anything about these? Are collectors interested in this sort of stuff?