The piece is indeed "Mouth Music" by Dolores Keane and John Falkner. About 15 years since it was first recorded. Reportedly Ewan MacColl used this song as a warm up piece.
The original recording was on "Dolores Keane" on ROUND TOWER RECORDS. I have it on the CD that Suibhan mentioned, and which I heartily recommend.
Celtic Mouth Music Musical Expeditions series Ellipsis Arts recording
For catalog or info:
Ellipsis Arts P.O. Box 305 Roslyn, NY 11576 (516)621-2727 (516)621-2750(fax)
Happy diddling. Marc B email: elliarts@aol.com