Hammie Nixon, born in 1908 in Brownsville, Tennessee, came up in the 1920s jug band scene playing kazoo, guitar and the jug itself, and this episode argues that those years taught him something that changed blues music. Playing jug meant buzzing your lips into a vessel to supply a syncopated bass line and lock the tempo, and Nixon carried that rhythmic thinking to the harmonica. Instead of using the instrument for flashy 30-second solos, he used breath patterns and mouth position to play chords and rhythm at once, turning a diatonic novelty into a chugging engine that could anchor an ensemble.

We trace his 50-year partnership with guitarist Sleepy John Estes, who was also his father-in-law, beginning with their first recordings for Victor in 1929 on the eve of the Great Depression, and his in-demand sideman work with Little Buddy Doyle, Lee ...