40. When these treaties and grants were concluded, Manlius, with the ten ambassadors, and all his army, marched to the Hellespont, and dictated to the chiefs of the Gauls, whom he had summoned thither, terms on which they should maintain peace with Eumenes; and warned them to put an end to the practice of straggling in arms, and to confine themselves within the bounds of their own territories. Then, having collected ships from all parts of the coast, and Eumenes’s fleet also being brought thither from Elæa by Athenæus, that king’s brother, he transported all his forces into Europe. Then leading slowly through the Chersonese, by short marches, the army heavily encumbered with booty of every sort, he halted at Lysimachia; in order that he might enter Thrace, the march through which they in general dreaded, with the beasts of burden as fresh and vigorous as possible. On the day in which he set out from Lysimachia, he came to the river which they call Melas,[35] and thence, next day, to Cypsela. The road, about ten miles from Cypsela, proved to be obstructed by woods, narrow and broken. On account of these difficulties he divided the army into two parts; and, ordering one to advance in front, and the other at a considerable distance, to cover the rear, he placed between them the baggage; it was composed of waggons with the public money, and other booty of great value. As he was marching in this order through the defile, a body of Thracians, not more in number than ten thousand, composed of four states, the Astians, Cænians, Maduatians, and Corelians, posted themselves on both sides of the road at the narrowest part. There was an opinion that this was not done without the treacherous connivance of Philip, king of Macedonia; that he knew that the Romans would return by no other route than that through Thrace, and what an immense sum they would carry with them. The general himself was in the van, anxious about the disadvantages of the ground. The Thracians did not stir until the troops passed by; but, when they saw that the foremost division had got clear of the narrow pass, and that the rear division was not yet drawing near, they rushed upon the encumbrances and the baggage, and after killing the guards, some rifled the waggons, while others led off the horses under their loads. After their shouts reached those on the rear, who were then just entering the pass, and afterwards those in the van, the Romans ran together from both extremities to the centre, and an irregular sort of fight commenced, in many different places at once. The booty itself exposed the Thracians to slaughter, as they were encumbered with burdens, and most of them had thrown away their arms, that they might have their hands disengaged for plundering; the disadvantageous nature of the ground militated against the Romans, as the barbarians attacked them through well-known paths, and sometimes lurked in the ravines. The loads too, and the waggons,