I see from Douglas's Peerage that it ought to be Archibald earl of Murray, (and not lord Douglas) third son to James VII. earl of Douglas. The earl of Ormond was his next brother.
The following extract is from Hutchinson's History of Northumberland, page 233, vol. ii.
'Henry earl of Northumberland, in the 14th Henry VI. made an unsuccessful irruption into Scotland,—and at Piperden was defeated by the earl of Angus, with the loss of 1500 men.
'In the 29th of the same reign he entered Scotland again, and engaged, near the river Sark, a large body of Scots under the command of sir William Wallace of Craigey, where he again had a defeat, and narrowly escaped being made prisoner,—his son choosing to throw himself into the hands of the enemy to save his father.'
[6] Sark,—a river in Scotland formed of two branches, the white and black, falls into the Eden four miles below Carlisle.
[7] De Couren. Couvren.——MS. Du Cange.
[8] Mortain,—a town in Normandy, on the river Lances, on the borders of Maine.
CHAP. IV.
THE KING OF FRANCE SUMMONS MANTES TO SURRENDER,—WHICH IT DOES, AND IS TAKEN POSSESSION OF, IN THE NAME OF THE KING, BY THE COUNT DE DUNOIS, HIS LIEUTENANT-GENERAL.
On the 26th of this same month of August, and on the morrow of the feast of St Louis, the king left Chartres with a noble company, and fixed his quarters at Château-neuf-en-Timerais[9], and, the same day, sent his heralds to summon the garrison of Mantes,—which town was held and occupied against his will. While the heralds were on their embassy, the counts de Dunois and St Pol arrived with five or six hundred combatants, the same day, before the town of Mantes, and summoned the inhabitants to return to their obedience to the king of France. They at first refused, from fear of the garrison, although in their hearts they were well inclined to obey the summons,—and the lieutenant-general ordered preparations for an immediate attack.