OK, Steve G, I know about the renaissance/baroque fashion for writing "Scotch" songs. Pills To Purge is a mixture of pre-existing material and new songs. My Scots is virtually non-existent, so I can't tell good from bad, authentic from fake. But I'd still like to know what the song's getting at!

Below I have reproduced the words with the bits that puzzle me in CAPITALS.

Bonny Peggy Ramsey that any Man may see,
And bonny was her Face, with a fair freckel'd Eye,
Neat is her Body made, and she hath good Skill,
And square is her WETHERGIG made like a Mill:
With a hey trolodel, hey trolodel, hey trolodel lill,
Bonny Peggy Ramsey she gives weel her Mill.

Peggy to the Mill is gone to grind a Bowl of Mault,
The Mill it wanted Water, and was not that a fault;
Up she pull'd her Petticoats and piss'd into the Dam,
For six Days and seven Nights she made the Mill to gang;
With a hey, &c.

Some call her Peggy, and some call her Jean,
But some calls her MIDSUMMER [WHY MIDSUMMER?], but they all are mista'en;
For Peggy is a bonny Lass, and grinds well her Mill,
For she will be Occupied when others they lay still:
With a hey, &c.

Peg, thee and Ise GRIN A POKE, and we to WAR WILL LEANES,
Ise lay thee flat upon thy Back and then lay to the steanes;
Ise make HOPPER TITTER TOTTER, haud the Mouth as still,
When twa sit, and eane stand, merrily grind the Mill:
With a hey, &c.

Up goes the CLAP [WHAT IS A CLAP ON A MILL?], and in goes the Corn,
Betwixt twa rough steans Peggy NOT TO LEARN [MEANING?];
With a Dam full of Water that she holdeth still,
To pour upon the Clap for BURNING [WHY BURNING?] of the Mill:
With a hey, &c.

Up she pull'd the Dam sure and let the Water in,
The Wheel went about, and the Mill began to grind:
The spindle it was hardy, and the steanes were they well pickt,
And the Meal fell in the Mill Trough, and ye may all come LICK [= LIKE?]:
With a hey trolodel, hey trolodel, hey trolodel lill,
Bonny Peggy Ramsey she gives weel her Mill.