In 1846 the Treaty of Washington (Oregon Treaty) contained a clause about the sea boundary following the "middle of the channel" thus leading to a dispute that would not be resolved until 1872. This map shows three proposed boundaries between the U.S. and British Columbia introduced to resolve the dispute. In arbitration Kaiser Wilhelm awarded to the U.S. the boundary it claimed (the western most of the lines). A very detailed and early depiction of the San Juan Islands. A scarce issue, published by John T. Bowen & Co.