Meanwhile Middleton had outwitted Morgan. Breaking up his force he had slipped it piecemeal over the hills and had joined his friends in Lochaber. It was the signal for active operations. Leaving a small force to cover Glasgow, and ordering up the Border horse under Colonel Howard in support, Monk suddenly shifted on to the Perth line and plunged into the hills. He meant if possible to drive the enemy through the gap he had left into the Lowlands, where they would fall an easy prey to his horse, or, if that failed, to force them northward. Moving with startling rapidity he was soon entangled in the wildest of the enemy's mountains and morasses. It was a country which till Deane's demonstration two years ago had been considered inaccessible to Lowland troops. It swarmed with roving bands of Highlanders; every straggler was a doomed man; the horse could hardly move, and the whole work of the march was arduous beyond all experience. But bold as was Monk's project its execution was cautious in the extreme. Every step of the way he made good. The country was systematically ravaged and every castle of strategic importance captured, garrisoned, and turned into an advanced magazine, according to the somewhat cumbrous and pedantic system which Monk and his contemporaries were then introducing. To prevent surprise and give time for properly securing his quarters he never marched after mid-day, nor did he ever move without flanking parties and a cloud of scouts. He marked out each camp and placed every picket and sentry himself, and was, in short, the head and heart alike of his over-worked force. Indifferent to hunger and sleep himself, he took every care of his men. He doctored and dosed them with his own hand, and by his elaborate system of magazines he kept them well supplied with biscuits and cheese. At the same time he took care his officers should not grumble. When the day's work was done it was his wont to unbend in frankest good fellowship. Then while his canteen was unpacked it was his delight to sit on the grass beside it and pitch joints of cold meat to his officers, who gathered round. No one could bear the hardships of a campaign better than tough "old George," and no one knew better how to lighten them.