cover 1897 envelope posted from the Chinese Post Office, Hankow to Vienna via Shanghai showing a fine strike of the despatch "dollar chop" dated 31 Aug. (new syle calendar) and bearing unoverprinted 10k. vertical pair cancelled by double ring d.s. (Type 1) in purple dated 27 Aug. (old style calendar), with another strike on reverse, a very early usage of this h.s., also showing Hong Kong and arrival c.d.s. A fine and important early item. Photo