Then there are other lyrics to this song which may come from a book called "Songs of the Gael" which is mostly a collecion made by Petrie.
Lucy
Can I check something, please? Are you thinking of An t-ath Breathnach's "Songs of the Gael" which is a large collection of English words set to old Irish airs? I don't see the song there - at least not under the "Foggy Dew" title.