1887-1900 two covers (opened for display), one franked with 5c brown, with violet "U.S. Postal Agency Shanghai" (21 Oct 87) datestamp and Flushing New York arrival pmk alongside; the other sent in 1900 from Boston to Chefoo, with U.S. Postal Agency Shanghai arrival and transit pmks on back, fine pair of outgoing and incoming letters (Image)