Now here's an odd thing.  I was looking for something else just now, and checked  LYRA CELTICA  (1896, revised ed. 1924).  What should I run into but this:

O'er the Muir amang the Heather  [Attributed to] Jean Glover (1758-1800), with this comment:

 The author of "O'er the Muir amang the Heather" was the daughter of a Highland weaver settled in Kilmarnock.  She married a strolling actor, and her fugitive songs became familiar throughout the West of Scotland.  "O'er the Muir amang the Heather" has become a classic.

Have a look and see what you think.