This song was written by John Gay (1685-1732) with help from Alexander Pope and Dean Swift in praise of the barmaid of the Rose Inn, Wokingham, and so Berkshire can lay claim to it rather than Gloucestershire. The poem was published in 1726 in “Mist’s Weekly Journal”. Complete words may be found here:
http://en.wikipedia.org/wiki/The_Ballad_of_Molly_Mogg.
It is interesting that in Gloucestershire the piece became a vehicle for local dialect, having been performed in the family since the late 18th century. This seems to be the only time it has surfaced in oral tradition.
Notes by Gwilym Davies