Thanks for the excellent advise on researching the steamship. I really lucked out in finding a posting from "The New York Times" 7/27/1864 that talked about the "B.M. Runyon" striking a snag on the Mississippi River on 7/21/1864 and sinking. On board were about 600 people, 440 were from the 10th Missouri Cavalry. The article said about fifty lives were lost. The place where the ship sank was called Griffith's Landing in this article. It was fifteen miles below Greenville, Mississippi.