Hi, Nigel -
"A Farmer's Son So Sweet" was a real "find." What books or other resources contain songs Sharp collected in the British Isles? I have Folk Songs from the Southern Appalachians, but not much from the UK other than The Idiom of the People (Reeves - 115 songs collected by Sharp, lyrics only); and a Dover reprint of a 1916 book called One Hundred English Folksongs, edited by Sharp. Is that all there is? Can you tell us more about the book you have?
Since Folk Songs from the Southern Appalachians, is so comprehensive, I'm surprised Sharp didn't do something equally significant for the British Isles.
-Joe-