Possibly the best part of the Katharine Hepburn epic, "Mary of Scotland" (1936) comes when Fredric March, as Bothwell, leads a parade of pipers and drummers into Edinburgh Castle.

They're playing a splendid march that I can't identify.

A piping website claims it's "Blue Bonnets over the Border," but it sound nothing like that tune.

Somebody must remember the scene and the tune. (Unfortunately, the scene is no longer on YouTube.)

What could it be?