Noel,
I looked up the Christy Moore version in the Christy Moore songbook. It is such a close match to the version Barry posted that I think it is easy to find out all words on Prosperous with Barry's version on the lap. If you think it is necessary I would type the other version, but couldn't do so before about two weeks.
In another source, the song is said to come from a broadside, so perhaps it has no known composer.

Wolfgang