Jim - I see that neither Ford nor Ord give Tannahill as author, though McColl's sleeve notes do (as, apparently, do several other sets).

I don't know if you know of this page: Complete Tannahill. Despite it's title, it's not complete yet, though it intends to be. The songs from the 1825 Glasgow edition are all there and don't include it, but there are more songs to come. On a quick look through, it didn't appear to be in the 1900 The Soldier's Return either.

So the site is not much help yet, but there is a contact for Dr.Steve Sweeney-Turner (who is managing and hosting the project) on the about page and it might be worth emailing him to see if he can help you.

Mick