C. Julius Caesar, Gallic War

Caesar, observing that several of his men were wounded, ordered the cohorts to ascend the mountain on all sides, and, under pretense of assailing the walls, to raise a shout: at which the besieged being frightened, and not knowing what was going on in other places, call off their armed troops from attacking our works, and dispose them on the walls. Thus our men without hazarding a battle, gained time partly to extinguish the works which had caught fire, and partly to cut off the communication. As the townsmen still continued to make an obstinate resistance, and even, after losing the greatest part of their forces by drought, persevered in their resolution: at last the veins of the spring were cut across by our mines, and turned from their course. By this their constant spring was suddenly dried up, which reduced them to such despair that they imagined that it was not done by the art of man, but the will of the gods; forced, therefore, by necessity, they at length submitted.