cover 1891 (29 May) XU5 from "United States Consulate at Ningpo, China" to Boston (29.6 arrival) bearing 5c. cancelled by oval of bars and showing adjacent a fine strike of the rare oval double ring "U.S. POSTAL AGENCY/SHANGHAI" datestamp applied in violet (Riddell Type 3). An uncommon h.s. in a colour unrecorded by Riddell. Also 1905 folded XU5 from Hankow to Arkansas bearing 2c. cancelled at Shanghai. Photo for first.