As Nick Dow said - Barbara Berry wrote a tune to a song that became very popular......and Barbara was an old old friend of mine - and I can tell you her and Len (her husband) were very very pleased with the regular cheques they received for the covers of the song....They probably made more from that than I have from 3 Traditional song based CD's....
And before you ask - most - if not all of the songs on those CDs came from Manuscripts and collected singers who have LONG been dead!!!

Tim Radford