Titus Livius (Livy), The History of Rome, Book 21
D. Spillan, A.M., M.D., Cyrus Evans, Ed.

48. On the following night a slaughter was made in the Roman camp by the auxiliary Gauls, which appeared greater from the tumult than it proved in reality. [2] Two thousand infantry and two hundred horse, having killed the guards at the gates, desert to Hannibal; whom the Carthaginians having addressed kindly, and excited by the hope of great rewards, sent each to [p. 747]several states to gain over the minds of their countrymen. [3] Scipio, thinking that that slaughter was a signal for the revolt of all the Gauls, and that, contaminated with the guilt of that affair, they would rush to arms as if a frenzy had been sent among them, though he was still suffering severely from [4??] his wound, yet setting out for the river Trebia at the fourth watch of the following night with his army in silence, he removes his camp to higher ground and hills more embarrassing to the cavalry. [5] He escaped observation less than at the Ticinus; and Hannibal, having despatched first the Numidians and then all the cavalry, would have thrown the rear at least into great confusion, had not the Numidians, through anxiety for booty, turned aside into the deserted Roman camp. [6] There whilst, closely examining every part of the camp, they waste time, with no sufficient reward for the delay, the enemy escaped out of their hands; and when they saw the Romans already across the Trebia, and measuring out their camp, they kill a few of the loiterers intercepted on that side of the river. [7] Scipio being unable to endure any longer the irritation of his wound, caused by the roughness of the road, and thinking that he ought to wait for his colleague, (for he had now heard that he was recalled from Sicily,) fortified a space of chosen ground, which, adjoining the river, seemed safest for a stationary camp. [8] When Hannibal had encamped not far from thence, being as much elated with the victory of his cavalry, as anxious on account of the scarcity which every day assailed him more severely, marching as he did through the territory of the enemy, and supplies being no where provided, he sends to the village of Clastidium, where the Romans had collected a great stock of corn. [9] There, whilst they were preparing for an assault, a hope of the town being betrayed to them was held out: Dasius, a Brundusian, the governor of the garrison, having been corrupted for four hundred pieces of gold, (no great bribe truly,) Clastidium is surrendered to Hannibal. It served as a granary for the Carthaginians while they lay at the Trebia. [10] No cruelty was used towards the prisoners of the surrendered garrison, in order that a character for clemency might be acquired at the commencement of his proceedings.