Robert Chambers had another explanation for the hill (related in his ‘Picture of Scotland’ of 1827).
Michael Scot was an infamous magician in these parts – and he had three demons who served him: Prig, Prim and Pricker. They were such a nuisance that he had to keep them continually busy. After he’d got them to cleft the Eildon Hills and bridle the Tweed with a curb of stone, he got them twisting ropes of sand. And when they’d done that, he commanded them to level Largo Law. However, they’d only just started – chucking one shovelful, which landed to form Norrie’s Law – when they were called away to do something else.