Just a clarification about the following quoted above:

"This nursery song [My Dearie Sits] is thoroughly local, and dates from about the beginning of the last century. There is such an insignificant difference between the above tune and Dorrington Lads, that they are usually taken to be the same air. As it is, however, better to err in repitition than in omission, we have included both, premising that we have been unable to settle the question of priority of date."

They are NEVER taken to be the same air (in my experience). They are different in character, harmonic structure and melody. They are however both in 9/8 (or 9/4, old style). The earliest appearance of both is in the William Dixon pipe tune manuscript dated 1733-1738 (edited/published as The Master Piper by me in 1995 and 2002). The Dixon book was unknown to the editors of Northumbrian Minstrelsy. My Dearie is called Adam A Bell by Dixon but it's the same tune.