Foy meanwhile, thus covered by Clausel, made a march of surprising celerity. On the 17th he arrived at Toro, and learned that the Galicians blockading that place had cleared off as early as the 15th, and had taken the road for Benavente. He blew up the fort, and took on with him the garrison of 800 men. At Toro he was much nearer to Zamora than to Astorga, but he resolved to march first on the remoter place--it was known to be hard pressed, and the French force there blockaded was double that in Zamora. He therefore moved on Benavente with all possible speed, and crossed the Esla there, driving away a detachment of the Galician division (Cabrera’s) which had come from Valladolid, when it made an ineffectual attempt to hold the fords. On the 20th August he reached La Baneza, some sixteen miles from Astorga, and there received the tiresome news that the garrison had surrendered only thirty-six hours before to Castaños. The three battalions there, worn down by famine to 1,200 men, had capitulated, because they had no suspicion that any help was near. The Spanish general had succeeded in concealing from them all knowledge of Foy’s march. They laid down their arms on the 18th, and were at once marched off to Galicia: Castaños himself accompanied them with all his force, being fully determined not to fight Foy, even though his numbers were superior. The French cavalry pushed on to Astorga on the 21st, and found the gates open and the place empty, save for seventy sick of the late garrison, who had been left behind under the charge of a surgeon. It was useless to think of pursuing Castaños, who had now two days’ start, wherefore Foy turned his attention to Zamora. Here Silveira, though warned to make off when the enemy reached Toro, had held on to the last moment, thinking that he was safe when Foy swerved away toward Astorga. He only drew off when he got news on the 22nd, from Sir Howard Douglas, the British Commissioner with the Galician army, to the effect that Foy, having failed to save Astorga, was marching against him. He retired to Carvajales behind the Esla, but was not safe there, for the French general, turning west from Benavente, had executed a forced march for Tabara, and was hastening westward to cut in between Carvajales and the road to Miranda de Douro on the Portuguese frontier. Warned only just in time of this move, Silveira hurried off towards his own country, and was within one mile of its border when Foy’s advanced cavalry came up with his rearguard near Constantin, the last village in Spain. They captured his baggage and some stragglers, but made no serious endeavour to charge his infantry, which escaped unharmed to Miranda. Foy attributed this failure to Curto, the commander of the light horse: ‘le défaut de décision et l’inertie coupable du général commandant la cavalerie font perdre les fruits d’une opération bien combinée’ (August 23rd)[15]. This pursuit had drawn Foy very far