Marmont had allotted fifteen days as the term of resistance for these forts, but from the facility with which San Vincente caught fire, five would have been too many if ammunition had not failed. His calculation was therefore false. He would however have fought on the 23d, when his force was united, had he not on the 22d received intelligence from Caffarelli, that a powerful body of infantry, with twenty-two guns and all the cavalry of the north, were actually in march to join him. It was this which induced him to occupy the heights of Villa Rubia, on that day, to avoid a premature action, but on the evening of the 26th the signals, from the forts, having indicated that they could still hold out three days, Marmont, from fresh intelligence, no longer expected Caffarelli’s troops, and resolved to give battle on the 28th. The fall of the forts, which was made known to him on the evening of the 27th, changed this determination, the reasons for fighting on such disadvantageous ground no longer existed, and hence, withdrawing his garrison from the castle of Alba de Tormes, he retreated during the night towards the Duero, by the roads of Tordesillas and Toro. Wellington ordered the works both at Alba and the forts of Salamanca to be destroyed, and following the enemy by easy marches, encamped on the Guarena the 30th. The next day he reached the Trabancos, his advanced guard being at Nava del Rey. On the 2d he passed the Zapardiel in two columns, the right marching by Medina del Campo, the left following the advanced guard towards Rueda. From this place the French rear-guard was cannonaded and driven upon the main body, which was filing over the bridge of Tordesillas. Some were killed and some made prisoners, not many, but there was great confusion, and a heavy disaster would have befallen the French if the English general had not been deceived by false information, that they had broken the bridge the night before. For as he knew by intercepted letters that Marmont intended to take a position near Tordesillas, this report made him suppose the enemy was already over the Duero, and hence he had spread his troops, and was not in sufficient force to attack during the passage of the river. [Sidenote: July.] [Sidenote: See Plan, No. 3.]