In the meantime, this a link to a page in David Gregory's book "Victorian Songhunters." This gives some relevant background on Percy and Parsons. There is an important footnote on pg. 50 also:

Percy-Parsons

In Scottish and English Popular Ballads, Child included the following note on 75A:

A. The copy sent Percy in 1770 was slightly revised by Parsons; the original was communicated in 1775.
3*. along in. 4*. coud speed.
6*. make. 6*. their mourn.
10*. Parsons corrects bunch to branch. 7*. bell.

But you will see in the Percy papers, that in Parson's 1770 copy, names are spelled differently also.