Before I had worked out what the 'mystery volume' in Dundee's Wighton Collection actually was, I divided the two sets of irregularly interleaved pages into what I thought were two volumes. One was, I thought, more Scottish in flavour than the other one.
I identified the two source volumes, and felt rather proud of myself. This week, I received the scans of both source volumes from the British Library. Now I'm even happier: I've just discovered the title of the second volume - the one I thought was more Scottish - has a little, tiny subtitle:-
'Consisting of Irish, Welsh and Scotch Tunes'