I see there's a new thread on it, but sensibly referred the OP back to this thread. One of my favourite tunes, which I learned early on when starting button accordion. (Score in my button accordion book in key of G.)
Later I heard the Dervish recording of Cathy Jordan singing it in Gaelic on the "Live in Palma" album and was blown away by it. There is another version by Cathy on YouTube with her singing in English: the lyrics scroll on the clip, and are as Jim Carroll has given above.