XXXIV.-There lay between the two armies a valley, as already mentioned, not very deep, but of a difficult and steep ascent. Each was waiting till the enemy's forces should attempt to pass it, that they might engage with the advantage of the ground. At the same time, on the left wing, the entire cavalry of Publius Attius, and several light-armed infantry intermixed with them, were perceived descending into the valley. Against them Curio detached his cavalry and two cohorts of the Marrucini, whose first charge the enemy's horse were unable to stand, but, setting spurs to their horses, fled back to their friends: the light-infantry being deserted by those who had come out along with them, were surrounded and cut to pieces by our men. Varus's whole army, facing that way, saw their men flee and cut down. Upon which Rebilus, one of Caesar's lieutenants, whom Curio had brought with him from Sicily knowing that he had great experience in military matters, cried out, "You see the enemy are daunted, Curio! why do you hesitate to take advantage of the opportunity?" Curio, having merely "expressed this, that the soldiers should keep in mind the professions which they had made to him the day before," then ordered them to follow him, and ran far before them all. The valley was so difficult of ascent that the foremost men could not struggle up it unless assisted by those behind. But the minds of Attius's soldiers being prepossessed with fear and the flight and slaughter of their men, never thought of opposing us; and they all imagined that they were already surrounded by our horse, and, therefore, before a dart could be thrown or our men come near them, Varus's whole army turned their backs and retreated to their camp.