"I am waitin' on the levee, Waitin' for the steamboat to come down, I hope she's loaded pretty heavy, I hope she's loaded to the ground. I think I hear her whistle blowin'... It must be the Natchez or the Robert Lee."
The Natchez, built 1869, and the Lee, built 1866, were regular competitors on the Natchez/New Orleans run. In 1870, the two captains agreed to a race.
It wasn't an equal contest, though -- the Natchez (thought by many to have been the slightly faster boat) took an ordinary load of passengers and cargo; the Lee was stripped for the race and drove through a fogbank. The Lee won the race by seven hours -- six of which the Natchez spent waiting out the fog to protect her passengers' safety.
The race was famed in popular folklore (see, for instance, Botkin's Mississippi River Folklore, pp. 58-61), but it didn't really set any records; it was just a straight race. And, interestingly, true folk songs about it are rare. Wheeler's is the first I've encountered to mention it, and it's only a fragment; the real subject might be something else. - RBW