Harry Jackson's "tune" for this is at least three tunes. If someone were a more careful transcriber they might find that he varies the tune in fact for *every* verse. His reading is followed faithfully by Larry Hanks (now again of the Bay area, having once been a Northwester) on his album "Tying a Knot in the Devil's Tail" (and a splendid album it is, with the title track not the least of its pleasures).