Wellington, on discovering the regressive movement of Massena, promptly despatched a division on either route, and speedily put his whole army in pursuit, leaving the lines secured by a sufficient force. He marched on the routes of the Mondega and the Zezere, it being uncertain by which of these roads the French should retreat from Portugal. The Zezere, however, was supposed to be the line. Hill was pushed over the Tagus, to march on Abrantes; and Lord Wellington, believing that Santarem was occupied only by a rear-guard, notwithstanding the nature of the ground rendered an attack difficult and hazardous, resolved to force it without delay.[124] Every disposition was made; but fortunately the allied commander having remarked appearances, which induced him to suspect that recent field-works had been thrown up, on a closer examination detected such powerful means of defence, as occasioned him to countermand the order for advancing. Both armies went into cantonments; the allies with head-quarters at Cartaxo,--the French having chosen Torres Novas for theirs. Little of military interest occurred for some time, excepting that the Portuguese militias, under their English officers, were incessant in harassing the French. Grant, with the corps he commanded, obliged Gardanne to fall back with the loss of his baggage, while attempting to protect a convoy of stores and ammunition to the French posts on the Zezere. But this was counterbalanced by a reverse of fortune. Too much excited by success, a part of the Portuguese ordonanza[125] attacked Claparede at Trarnosa. The result was what might have been expected from a collision with regular troops; they were severely checked, and driven with considerable loss across the Douro. Time passed on,--nothing of moment occurred,--the British remaining quiet, in expectation of a reinforcement of troops from England. A strong _reconnaissance_, however, was made by the French at Rio Mayor, under the command of Junot, who was wounded on the occasion. A period of inaction succeeded--and each army rested in the other’s presence. The first movements that took place were an advance on Punhete by the allies, and the sudden retirement from Santarem by the French. Massena chose the left bank of the Mondego as his line of retreat, falling back on Guarda and Almeida. Wellington followed promptly; and on the 9th, Massena having halted in front of Pombal, the allies hastened forward to attack him. But the French Marshal declined an action, and fell back pressed closely by the British light troops, and covered by a splendid rear-guard which he had formed from his choicest battalions, and intrusted to the command of Marshal Ney.