18 miles to to an inch. Includes legend. At head of title: (No. 1). "Surveyor General's Office, Dubuque, October 13th, 1857, Warner Lewis, Surr. Genl." Sen. Ex. Doc. No. 11 and House Ex. Doc. No. 2, 1st Sess., 35th Cong.
United States. Surveyor General.; Lewis, Warner; C.B. Graham's Lith.
University of Minnesota Libraries, John R. Borchert Map Library.