In Kerr's book of Fiddle music, in a section on Slow Airs, there's a version of The Blackbird with a sentence or two telling how (I quote from memory) it's a staple of Irish traditional fiddlers, but no two of them ever plays it alike. There are words to it too, concerning the exiled Stuarts (James VII, the "Old Pretender" and father of Bonnie Price Cherlie, was known as the Blackbird), and one version can indeed be found in O'Lochlainn. Of course the set-dance is fairly similar, and much faster.