IV. The Belgæ having failed in taking the _oppidum_ of Bibrax, in drawing the Romans upon disadvantageous ground, in crossing the river, and suffering, also, from want of provisions, decided on returning home, to be ready to assemble again to succour the country which might be first invaded by the Roman army. The principal cause of this decision was the news of the threatened invasion of the country of the Bellovaci by Divitiacus and the Ædui: the Bellovaci refused to lose a single instant in hurrying to the defence of their hearths. Towards ten o’clock in the evening, the Belgæ withdrew in such disorder that their departure resembled a flight. Cæsar was informed immediately by his spies, but, fearing that this retreat might conceal a snare, he retained his legions, and even his cavalry, in the camp. At break of day, better informed by his scouts, he sent all his cavalry, under the orders of the lieutenants Q. Pedius and L. Aurunculeius Cotta,[251] and ordered Labienus, with three legions, to follow them. These troops fell upon the fugitives, and slew as many as the length of the day would permit. At sunset they gave up the pursuit, and, in obedience to the orders they had received, returned to the camp.[252] The coalition of the Belgæ, so renowned for their valour, was thus dissolved. Nevertheless, it was of importance to the Roman general, in order to secure the pacification of the country, to go and reduce to subjection in their homes the peoples who had dared to enter into league against him. The nearest were the Suessiones, whose territory bordered upon that of the Remi. [Sidenote: Capture of Noviodunum and Bratuspantium.] V. The day after the flight of the enemy, before they had recovered from their fright, Cæsar broke up his camp, crossed the Aisne, descended its left bank, invaded the country of the Suessiones, arrived after a long day’s march (45 kilomètres) before Noviodunum (_Soissons_) (_see Plate 7_), and, informed that this town had a weak garrison, he attempted the same day to carry it by assault; he failed, through the breadth of the fosses and the height of the walls. He then retrenched his camp, ordered covered galleries to be advanced (_vineas agere_),[253] and all things necessary for a siege to be collected. Nevertheless, the crowd of fugitive Suessiones threw themselves into the town during the following night. The galleries having been pushed rapidly towards the walls, the foundations of a terrace[254] to pass the fosse (_aggere jacto_) were established, and towers were constructed. The Gauls, astonished at the greatness and novelty of these works, so promptly executed, offered to surrender. They obtained safety of life at the prayer of the Remi.