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.