I recently heard from Meredith Willis of Richmond, Kentucky, who is on the family tree of Cassius M. Clay, probably the greatest bowie-knife fighter of American history, if not as famous as Jim Bowie. Willis collects Clay artifacts, and through a trade came into possession of one of his knives. Measuring 8.5-inches overall and made in or around 1870, its blade is marked "Franz Widmann & Sohn, Munchen" and its silver pommel is engraved "Cassius M. Clay, White Hall." It was authenticated by Katherine White, the curator from the White Hall Museum, and Phil Gray, a historic weapons expert. It is not a bowie knife as we would define that term today, but may be a knife Clay presented to a friend.
I thank Mr. Willis for sharing his story and the photos of his knife. Perhaps some day someone will send me a copy of Clay's elusive manual of bowie-knife fighting!