(Outgoing Philadelphia) 1855 Philadelphia, Pa. To Wurttemberg, Germany. Prussian closed mail rate cover with "Philadelphia, Pa., Apr 12" origin cds and matching "30" rate handstamp below, "N. York Am. Pkt., 23, Apr 18" exchange cds intentionally struck of Philadelphia cds, reverse with red Aachen transit cds and Alpirsbach receiving postmark, Very Fine, the earliest recorded use of this New York exchange marking. Estimate  $300 - 400. $0 (Image)