Although aware that there was a considerable force gathering at Coimbra, the French general had no idea that the whole of the British army was assembling there. Confident that success would attend his operations, Sir Arthur directed the Portuguese corps to be in readiness to harass Soult's retreat through the mountain denies and up the valley of the Tamega, and so to force him to march north instead of making for Salamanca, where he could unite with the French army there. A mounted officer brought similar orders to Terence. Half an hour after receiving them the corps was on the march. The instructions were brief and simple: _"You will endeavour to harass Soult as he retreats across the Tras-os-Montes, and try to head him off to the north. Act as circumstances may dictate."_ The service was a dangerous one, and Terence felt that it was a high honour that the general should have appointed him to undertake it, for he assuredly would not have sent the corps on such a mission had he not considered that they could be relied upon to take care of themselves. They would be wholly unsupported save by parties of peasants and ordenanças; they would have to operate against an army broken, doubtless, by defeat, but all the more determined to push on, as delay might mean total loss. He followed the line of the Vouga to the point where it emerged from the hills, crossed these, and came down upon the Douro some ten miles above San Joao, at nearly the same spot where he had before made the passage when on his way to join Romana. He was now well beyond the district held by the French south of the Douro, and, obtaining a number of boats, crossed the river, and then made for Mirandella on the river Tua, and halted some distance from the town, having made a march of over seventy miles in two days. Learning from the peasants that there were no French troops west of the Tamega, he marched the next day to the crest looking down into the valley, and here halted until he could learn that Soult was retreating, and what road he was following. He had not long to wait for news, for, on the night of the 9th, while he was on his march by the Vouga, the British force had moved forward to Aveiro. Hill's division had there taken boats, and proceeding up the lake to Ovar, had landed at sunrise on the 10th, and placed himself on Franceschi's right.