U.S.P.O., Philadelphia Pa., 1c Black on Vermilion Glazed (7LB8).
Large bottom margin, framelines at left and top, uncancelled, used on brown cover to Columbus O. and forwarded to Springfield, blue "Philada. Pa. Apr. 9" circular datestamp, red "Columbus O. 17 Apr." circular datestamp, ms. "15c/5"
due notation, slight toning, still Very Fine, unusual usage of a very scarce carrier stamp (14 reported covers)
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