150-200 years ago? That's not right, surely - the Bodleian is far older and has stuff more like 400-500 years ago! 200 years ago modern songwriters like Stephen Foster were cutting their teeth (literally, I think...) and by 150 years ago the pop music industry was almost detectable.

The watershed is 1765 - Percy and Herd. Ignore Allan Ramsay, Pepys, and various 'Garlands' since so much of it was plain awful art-song with poetastic words. But once Percy opened the doors, between than and 1830 you've got a whole bunch of collectors, imposters, inventors etc and that habit has never ceased.

What really matters is MS copies and blackletter stuff of a very early date, and 150-200 years ago is modern in folk song terms if you are looking for 'origins'.

Thanks for the site pointer - I shall use it!