In Newcastle's Robinson library I saw the 12 volume collected edition of Scott's "Poetical Works", published 1833. There are some tunes notated there, for example an "Ancient Tune" for Thomas the Rhymer, all of which come with a piano accompaniment. Unfortunately there is no information in the book about how Scott got the tunes, or who transcribed them. Scott died in 1832 and 1833 is as far as I know the only edition with tunes. Scott said himself that he was extremely unmusical, so somebody else must have added the music.

Any clues, anybody?