Scott says here:  “It may be necessary to inform the Southern reader that the heath on the Scottish moorlands is often set fire to, that the sheep may have the advantage of the young herbage produced, in room of the tough old heather plants.  This custom (execrated by sportsmen) produces occasionally the most beautiful nocturnal appearances, similar almost to the discharge of a volcano.  This simile is not new to poetry.  The charge of a warrior, in the fine ballad of Hardyknute, is said to be ’like fire to heather set.’”

575.  Nor faster speeds it, etc.  “The eager fidelity with which this fatal signal is hurried on and obeyed, is represented with great spirit and felicity” (Jeffrey).

577.  Coil.  Turmoil.  Cf.  Shakespeare, Temp. i. 2. 207: 

    “Who was so firm, so constant, that this coil
     Would not infect his reason?”

C. of E. iii. 1. 48:  “What a coil is there, Dromio?” etc.

579.  Loch Doine.  A lakelet just above Loch Voil, and almost forming a part of it.  The epithets sullen and still are peculiarly appropriate to this valley.  “Few places in Scotland have such an air of solitude and remoteness from the haunts of men” (Black).

582.  Strath-Gartney.  The north side of the basin of Loch Katrine.

583.  Each man might claim.  That is, who could claim.  See on i. 528 above.

600.  No law but Roderick Dhu’s command.  Scott has the following note here: 

“The deep and implicit respect paid by the Highland clansmen to their chief, rendered this both a common and a solemn oath.  In other respects, they were like most savage nations, capricious in their ideas concerning the obligatory power of oaths.  One solemn mode of swearing was by kissing the dirk, imprecating upon themselves death by that, or a similar weapon, if they broke their vow.  But for oaths in the usual form, they are said to have had little respect.  As for the reverence due to the chief, it may be guessed from the following odd example of a Highland point of honour: 

’The clan whereto the above-mentioned tribe belongs, is the only one I have heard of which is without a chief; that is, being divided into families, under several chieftains, without any particular patriarch of the whole name.  And this is a great reproach, as may appear from an affair that fell out at my table, in the Highlands, between one of that name and a Cameron.  The provocation given by the latter was, “Name your chief.”  The return of it at once was, “You are a fool.”  They went out next morning, but having early notice of it, I sent a small party of soldiers after them, which, in all probability, prevented some barbarous mischief that might have ensued; for the chiefless Highlander, who is himself a petty chieftain, was going to the place appointed with a small-sword and pistol, whereas the Cameron (an old man) took with him only his broadsword, according to the agreement.