Wonder what the origin of this is. It is noteworthy that all words at the end of lines are monosyllabic; there is end-rhyme between lines b and d; and, there is internal rhyme in lines b and d with the finals of lines a and c respectively. LInes of seven syllables abound but there are a few of only six. Those lines might repay further scrutiny as to possible corruption although the metre may have always been of this form. Definitely not a folk composition - this poet knew the game.