Meanwhile, Heudelet’s division, having pushed back the advanced guards of the duke del Parque upon Ciudad Rodrigo, ascertained that a great movement of troops was taking place near that city, and that sir Arthur Wellesley, advancing quicker than was expected, had already reached Plasencia; wherefore, on the 18th, Soult directed Mortier to march upon Salamanca with the fifth corps, and, at the same time, reinforced Heudelet’s division with Merle’s; the latter’s place, at Zamora, being supplied by a division of the sixth corps, the remainder of which continued on the Esla, fronting the Tras os Montes. Thus, not less than fifty thousand men were at or close to Salamanca, with their cavalry-posts pointing to the passes of Baños, on the very day that sir Arthur Wellesley crossed the Tietar to effect his junction with Cuesta. Yet, neither through the duke del Parque, nor Beresford, nor the guerillas, nor the peasantry, did intelligence of this formidable fact reach him! Having put the three corps in motion, Soult despatched general Foy to Madrid, with information of sir Arthur’s march, and to arrange the future combinations of the two armies. “_It is probable_,” he said, “_that the concentration of my army at Salamanca will oblige the English general to change his plan; but, if he shall already have advanced on the road to Madrid, we should assemble all our forces, both on the Tagus and on this side, fall upon him altogether, and crush him. Thus, his campaign will be finished, and our operations may go on with advantage._” Foy arrived, the 22d, at Madrid; and, a few hours afterwards, intelligence reached the king that the allies were at Talavera, in front of the first corps, and that sir Robert Wilson (whose strength was much exaggerated) was at Escalona. The die was now cast; Joseph directed Soult to march immediately upon Plasencia, then, leaving general Belliard, with only three thousand men, in the Retiro, set out himself, with his guards and reserve, by the road of Mostoles, to join Victor at Talavera. The 23d, being at Naval-Carneiro, he received notice that the first corps would retreat that night to Torrijos, and, in two days, would be behind the Guadarama river; whereupon, turning to the left, Joseph descended the Guadarama to Vargas, and effected his junction with the duke of Belluno on the 25th.