Thanks very much, both. I might have expected chapter and verse from you, Steve! The name of the Irish tune I cannot remember, though it is very well known. Expressed in (vaguely) ABC notation, it's a 3/4 jig of nearly all crotchets, and starts cA GEG GEG AFA AcA GEG Gcd edc AcA GEG GEG AFA A2A cde ged cAA A2 and so on. My command of ABC is even worse than my memory, but it should give you the idea - I hope!
Cheers
Simon