Transcripts of the diaries kept by Carl Julius Adolph Hunnius documenting his surveys of the Red River, January 10, 1876 to January 24, 1876, and April 25, 1876 to June 30, 1876. The collection also includes the original diary of the second survey, a biography of Ado Hunnius, and two tintypes and print copies of Hunnius and his guide Billy Dixon.

Letter dated January 30, 1883 from O.O. Potter, a newly-arrived Sumner County, Kansas settler, describing his impressions of the county and his 1882 rail travels in Texas, New Mexico, and Colorado.