Caesar had no cavalry; but every Gaul could ride, and he raised a few thousand horse among his supposed allies. These he meant to employ to harass the Helvetian march; but they were secret traitors, under the influence of Dumnorix, and they fled at the first encounter. The Helvetii had thus the country at their mercy, and they laid it waste as they went, a day's march in advance of the Romans. So long as they kept by the river, Caesar's stores accompanied him in barges. He did not choose to let the Helvetii out of his sight, and when they left the Saône, and when he was obliged to follow, his provisions ran short. He applied to the Aeduan chiefs, who promised to furnish him, but they failed to do it. Ten days passed, and no supplies came in. He ascertained at last that there was treachery. Dumnorix and other Aeduan leaders were in correspondence with the enemy. The cavalry defeat and the other failures were thus explained. Caesar, who trusted much to gentleness and to personal influence, was unwilling to add the Aeduii to his open enemies. Dumnorix was the brother of Divitiacus, the reigning chief, whom Caesar had known in Rome. Divitiacus was sent for, confessed with tears his brother's misdeeds, and begged that he might be forgiven. Dumnorix was brought in. Caesar showed that he was aware of his conduct; but spoke kindly to him, and cautioned him for the future. The corn-carts, however, did not appear; supplies could not be dispensed with; and the Romans, leaving the Helvetii, struck off to Bibracte, on Mont Beauvray, the principal Aeduan town in the highlands of Nivernais. Unfortunately for themselves, the Helvetii thought the Romans were flying, and became in turn the pursuers. They gave Caesar an opportunity, and a single battle ended them and their migrations. The engagement lasted from noon till night. The Helvetii fought gallantly, and in numbers were enormously superior; but the contest was between skill and courage, sturdy discipline and wild valor; and it concluded as such contests always must. In these hand-to-hand engagements there were no wounded. Half the fighting men of the Swiss were killed; their camp was stormed; the survivors, with the remnant of the women and children, or such of them as were capable of moving (for thousands had perished, and little more than a third remained of those who had left Switzerland), straggled on to Langres, where they surrendered. Caesar treated the poor creatures with kindness and care. A few were settled in Gaul, where they afterward did valuable service. The rest were sent back to their own cantons, lest the Germans should take possession of their lands; and lest they should starve in the homes which they had desolated before their departure, they were provided with food out of the Province till their next crops were grown.