Lot 50621851 (Sep. 30) San Francisco Cal. to Herford, Prussia, gray folded letter showing red "San Francisco Cal., 1 Oct" cds with matching "Paid" and "26" rating handstamp, additional pencil "26" cent prepayment rating, carried by Collins Line Pacific from New York Nov. 8th to Liverpool arriving Nov. 19th, red London (11.20) transit backstamp with black "U.S. Pkt." straightline and "10" pence debit to Prussia, Aachen red "Seebrief per England and Aachen" (11.21) double-circle transit backstamp and blue ms. "11 1/3" sgr. due rating, Very Fine and scarce California use.
Estimate $300 - 400.
The convention permitted the US to charge 10¢ domestic postage from the West Coast because of the added expense. For example, the top cover went by steamship from San Francisco to Panama, was carried across the isthmus to the port of Chagres, and then sent by steamship to New York.