cover 3c Orange Brown (10), pos. 31R1E, huge margins at sides showing pane margin at left and bit of next stamp at right, others touching to slightly in (at top), well-tied by black grid on fresh blue folded letter (undated) to Milton, Mass., blue "Baltimore, Md. Jul 1 (1851)" first day pmk., very fine, with 1967 Tracy Simpson letter confirming 1851 usage (thus a first day usage), he notes that plate 1 early was not printed after the first week or so in July of 1851 and that a major city such as Baltimore would not have a supply of plate 1 early stamps still on hand in July of 1852 (one year later), with 1993 P.F. certificate which states "genuine usage on folded letter without year date, but believed to have been used July 1, 1851", ex Kapiloff, a very desirable classic first day cover, a fabulous rarity in every respect, Scott retail $12,500.00 photo