- Richard L. Woodyard Papers, 1808/18721
- Roy Riethmiller, Artist, Three Prints of Artistic Renderings, 1983/19921
- Roy Thistle, Collector, Scrapbook regarding Ohio River History, 1855/19341
- Speech by Logan, Chief of the Mingo Tribe (manuscript copy), 17801
- Steamboats Records, 1877/19391
- Steamboats Records, 18831
- Steamboats Records, 1929/19391
- Thomas Browse Family Papers, 1785/1942, bulk 1830/19101
- Thomas Hanson Journal, 17741
- U.S. Army Corps of Engineers, Photographs of Operations in Pennsylvania, Ohio, New York, and the Pacific Northwest, 1914/19191
- William Starke Rosecrans (1818-1898) Correspondence, 1841/18791
- Willis DeHass, Historian, Scrapbook regarding Ohio River Valley, 1868/18791
- Woodbridge-Blennerhassett Papers, 1797/19351
- Wylie-Tomlinson Letter Collection regarding the Civil War and Other Topics, 1834/19141