The Guarena, flowing from four distinct sources which united below Castrillo, offered a very strong line of defence; yet Marmont, hoping to carry it in the first confusion, brought up all his artillery and pushed the head of his right column over an upper branch. Wellington, expecting this, had previously ordered up the other divisions of his army, and they were in line before Marmont’s infantry, oppressed with heat and long marches, could gather strength to attempt the passage of the other branch. Carier’s brigade of cavalry first crossed, and was followed by a column of infantry, just as the fourth division had gained the table-land above. Carier’s horsemen entered the valley on the left, the infantry in one column menaced the front, but the sedgy banks of the stream would have been difficult to force, if Victor Alten, slow to perceive an advantage, had not suffered the French cavalry to cross first in considerable numbers without opposition. Then he assailed them by successive squadrons instead of regiments, and when the 14th and German Hussars were hard-pressed, brought up the 3rd Dragoons, who were however driven back by the fire of the infantry, and many fell. Finally Carier being wounded and taken, the French retired, and meanwhile the 27th and 40th Regiments, coming down the hill, broke the enemy’s infantry with an impetuous bayonet charge: Alten’s horsemen then sabred some of the fugitives. Marmont lost a general and five hundred soldiers by this combat, but, though baffled at one point, and beaten at another, he concentrated his army and held both banks of the branch he had gained. Wellington also concentrated, and as the previous operations had only cost him six hundred men and the French but eight hundred, the day being still young, the positions open and within cannon-shot, a battle was expected. Marmont’s troops had however been marching for two days and nights, and Wellington’s plan did not admit of fighting unless in defence, or with such advantage as that he could crush his opponent and keep the field afterwards against the king. The French marshal had passed a great river, surprised the allies’ right, and pushed it back above ten miles: he had nevertheless failed as a general. His aim had been, by menacing the communication between Salamanca and Rodrigo, to draw the allies back; yet on the evening of the 16th, having passed the Duero at Toro, he was nearer to Salamanca than they were, and, persisting, Wellington must have fought him at disadvantage, or passed the Tormes at Huerta to regain the road of Rodrigo. Marmont however relinquished this stroke to march eighty miles in forty-eight hours, and after many nice evolutions, in which he lost a thousand men by the sword and fatigue, found his adversary on the 18th facing him in the very position he had turned on the evening of the 16th!