The value of this double line of defence for the Lowlands was well shown in 1715. When Mar lay so long idle at Perth with the largest Jacobite army ever mustered could he have held it together, his inactivity was caused not only by want of skill and decision, but by the fact of the Forth fords being swollen by a wet winter, while Argyll had broken down the Teith Bridge at Doune. Mar found it easier to ship a detachment across the Firth of Forth than to get over the river near its source, an enterprise in which sly Rob Roy seems to have been in vain expected to guide him. When he did advance on Stirling it was by Allan Water, above which he met Argyll on Sheriffmuir, for that strange battle in which both sides were half-losers, half-winners. Argyll’s moral victory appears to have been partly due to the Ochil boglands being frozen so as to bear the heavy regular dragoons. A little later and the frost would have been hard enough to make the unbridged rivers passable, as the Highland army could retreat from Perth across the ice-bound Tay. When Charles Edward advanced upon the Lowlands it was in a dry September that let him easily over the Forth, to march on in bravado within cannon-shot of Stirling Castle. To hinder his retreat he found Stirling Bridge broken down, which was repaired in haste for Cumberland’s march to the north. Sheriffmuir, if we may trust historians like Blind Harry, was arena of an older and a bloodier battle, when Wallace is said to have exterminated an English army ten thousand strong; and scattered standing stones here are taken by the country-folk as memorials of that victory. The little town of Dunblane, with its restored Cathedral and its monuments of nobility, was well known to armies marching north and south on the road up Strathallan into Strathearn. Prince Charlie and Butcher Cumberland were lodged here in turn; and local legend makes the latter narrowly escape an end worse than that of Pyrrhus. A servant lass whose heart had been won by the Prince’s graciousness when she cleaned his boots, undertook to souse the Duke with boiling oil thrown from a window as he rode out of Dunblane; but the scalding douche lighted on his horse’s haunch, so that he got off with being flung into the mud.