In 1849 U. S. Army Lieutenant George H. Derby performed topographical survey of the Sacramento Valley. The “Topographical Memoir Accompanying Maps of the Sacramento Valley, &c.” was found in Quarterly of the California Historical Society Vol. XI No. 2 publication dated June 1932. I found the small quarterly report in a book store in San Francisco and was attracted to it because of the inset map of the Sacramento Valley. The map is a reproduction of Lieutenant Derby’s topographical map he made for his report.
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