cover 1876 (13 Dec.) Eetvelde envelope to Anvers, Belgium bearing a pair of 1862 18c. (some perforation faults) cancelled by a good strike of the "C1" obliterator, the reverse shows an array of transit marks including "CUSTOMS/CANTON" double-ring c.d.s. and the straight-line Canton c.d.s. This is a rare, double rate cover used during the period of the 18c. per ¼ ounce rate by French packet to Europe (27 Jan. 1876 to 1 Apr. 1877). Holcombe Certificate (1998). Photo