Explorations and Surveys for a Rail Road Route from the Mississippi River to the Pacific Ocean. War Department. Route near the 41st Parallel. Map No. 4. From the Mud Lakes to the Pacific Ocean; from Explorations and Surveys made under the direction of the Hon. Jefferson Davis Secretary of War.
Size: Printed area measures 21 x 18 inches (53.34 x 45.72 centimeters)
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