This tune was used by Robert Burns for the original setting of his lovely poem “Ae Fond Kiss”.
The only source for this tune I have ever found is two publications by James Oswald. I do not know the exact date of either of these books; they are both from around 1750.
This is the famous Caledonian Pocket Companion (book 8, p24):
And here it is with a baroque bass for harpsichord or cello, in A Collection of 43 Scots tunes with variations:
This tune is often claimed for either Ruaidhrí Dall Ó Catháin or Rory Dall Morrison. On the other hand, various authors including John Purser and David Johnson have suggested that it looks more like Oswald’s own work.
I have played this tune for a while - I included a complete version with Oswald’s variations on Clàrsach na Bànrighe, and I have played it to accompany Sheena Wellington singing “Ae Fond Kiss”, but have always thought it was not particularly convincing as a piece of ancient harp idiom. My suspicion was strengthened when I read recently about Oswald’s common use of pseudonyms when publishing tunes (a common enough thing in mid 18th century Scottish literary circles I understand). Perhaps we should simply add “Rory Dall” to the list of Oswald’s pseudonyms alongside “Rizzio” and “Dottel Figlio”.