Go raibh míle maith agaibh, A Mhick agus a Mhartin.

I found this information here at the Rounder Records site, which comes from the liner notes of The Boys Of The Lough's CD, Live At Passim:

The song to which the slow air belongs is called in Irish "Ar Eirinn Ni 'Neosfainn Ce Hi" ("For Ireland I'd not tell her name") and it is written in praise of a beautiful maiden who appeared for a short time to a Gaelic poet, resisted his advances and then disappeared for ever. The tune here used is to be found in Joyce's Old Irish Folk Music and Song, where it appears as "Nancy the Pride of the West" (O.I.F.M.S. No. 410 p.221). Joyce also gives the Irish words and music in Irish Music and Song (p. 22). See also Ceol ar Sinsear p. 91 (Browne & Nolan, Dublin 1934). Those who are familiar with the English-Scots border country may see a resemblance to the song known as "Tweedside."

I know that it may not be of much help to you, Martin; but, at least it gives a page number in Ceol ár Sinsear for you to go to, if necessary. *BG*

Buíochas arís, Áine