“Abies Williamsonii.” From R.S. Williamson and Henry L. Abbot, Explorations and Surveys for a Railroad Route from the Mississippi River to the Pacific Ocean…Routes in California and Oregon. Volume VI: California & Oregon. Drawing by Charles Koppel. Washington, GPO, 1857. Tinted lithograph. Very good condition.
Besides the four main east-west routes for the transcontinental railroad, two supplemental surveys were sent out to explore the north-south routes in the far west. An expedition under Lieutenant R.S. Williamson was sent to survey a possible route between the 32nd and 35th parallels. There was another California survey expedition, under Lieutenants Williamson and Henry L. Abbot, which was sent to search for the best route between the Sacramento Valley and the Columbia River. The botanical and zoological illustrations from this volume are also of considerable interest.