In the mean while Cromwell had obtained[b] possession of the castle of Edinburgh through the perfidy or the timidity of the governor. Tantallon had been taken by storm, and Dumbarton had been attempted, but its defences were too strong to be carried by force, [Footnote 1: Carte, Letters, ii. 26, 27. Balfour, iv. 240, 268, 281, 301. It appears from this writer that a great number of the colonels of regiments were royalists or engagers (p. 210, 213). The six brigades of horse seem to have been divided equally between old Covenanters and royalists. The seventh was not given to any general, but would be commanded by Hamilton, as the eldest colonel.--Ib. 299-301. It is therefore plain that with the king for commander-in-chief the royalists had the complete ascendancy.] [Sidenote a: A.D. 1651. May 21.] [Sidenote b: A.D. 1650. Dec. 19.] and its garrison too honest to be corrupted with money.[1] In February the lord general was afflicted[a] with an ague, so ruinous to his health, and so obstinate in its duration, that in May he obtained permission to return to England, with the power of disposing, according to his judgment, of the chief command.[2] A rapid and unexpected improvement[b] induced him to remain; and in July he marched with his army towards Stirling. The Scots faced him in their intrenched camp at Torwood; he turned aside to Glasgow; they took[c] a position at Kilsyth; he marched[d] back to Falkirk; and they resumed their position at Torwood. While by these movements the English general occupied the attention of his opponents, a fleet of boats had been silently prepared and brought to the Queensferry; a body of men crossed the frith, and fortified a hill near Inverkeithing; and Lambert immediately followed[e] with a more numerous division. The Scots despatched Holburn with orders to drive the enemy into the sea; he was himself charged[f] by Lambert with a superior force, and the flight of his men gave to the English possession of the fertile and populous county of Fife. Cromwell hastened to transport his army to the left bank of the river, and advance on the rear of the Scots. They retired: Perth, the seat of government, was besieged; and in a few days[g] the colours of the commonwealth floated on its walls.[3] [Footnote 1: Balfour, iv. 229, 249, 296. Baillie, ii. 368.] [Footnote 2: The council had sent two physicians to attend him. His answer to Bradshaw of March 24th runs in his usual style. "Indeed, my lord, your service needs not me. I am a poor creature, and have been a dry bone, and am still an unprofitable servant to my master and to you."--New Parl. Hist. iii. 1363.]