Huddie Ledbetter aka ‘Leadbelly’ was famous as a guitarist and vocalist with a wide range of repertoire, much of it from the early blues and songster tradition. He recorded a few piano solos including Eagle Rock Rag, The Eagle Rocks, and Big Fat Woman which are all essentially the same piece, featuring some singing and a lot of scat. These recordings resemble blues rather than ragtime and have a unique feature of a left hand “Alberti bass” figure throughout.
In this transcription the phrases are 8 bars, but it seems likely that Eagle Rock Rag is actually a very fast 16-bar blues, which is somewhat common among country blues recordings. The formula is the same as the usual 12-bar blues with three stanzas except the second stanza is repeated: I I I I – IV IV I I – IV IV I I – V V I I.
Leadbelly’s piano solos, Eagle Rock Rag and The Eagle Rocks, can be found on Leadbelly Vol 4 from Document Records.