19th Century Used Entires Group, five covers including UPSS 644 with typewritten address from the Centennial Exposition, 1167 to Vienna with World's Fair Station cancel, 1178 uprated and registered to Amsterdam, 1363 with Hong Kong paquetboat datestamp addressed to Saigon, and 1364 with U.S. Postal Agency Shanghai datestamp addressed to Tsingtau, all fine to very fine and attractive, an interesting group