Anyone singing those two songs mixed up together like that, with bits missing and with that title, will have learned it from an old Dolores Keane record, or from someone who did. The two full texts, Gaelic and English, were posted several years ago: Dance to your Shadow.

I may as well repeat that the original question is very specific. Unless anyone has the lyric from The New Strung Harp (it was not given in the sleeve notes) or can identify the book it was taken from, there isn't a great deal of point in randomly quoting any song that comes to mind which has the meaningless vocable horo in it; many, many Scottish Gaelic songs include it, and it is also an Eastern European dance form come to that.