cover SINCHANG: 1899 (28 Mar.) red band envelope from Sinchang to Tientsin, via Canton, bearing, on the reverse, C.I.P. 2c. (3) tied by Canton Dollar chops and showing a fine strike of the rare, double-circle, Sinchang "IMPERIAL POST OFFICE" h.s., also a faint strike of Tientsin Dollar chop in blue along with unframed instructional marking. Photo