Arrived at the _vallum_ formed on the slant, they were received by a shower of stones and darts. But soon recovering the surprise, and urged on by their chiefs, the Franks sprang up the escarpment. Their position, commanded as it was by the besieged, was unfavourable, and the first assault failed. They had to rally in the shelter afforded by the habitations and hedges left by Clodoald outside the _vallum_. Hearing the shouts of the onslaught, the troops left near the passage hurried in their turn up the hill. Secondinus then judged it expedient to get over a thousand men from among those who had remained in the island, giving excellent reasons for keeping them at that point. Seeing the reinforcement ascending the hill, the first assailants separated into three large parties, and at the word of command advanced anew against the _vallum_. The fall of the foremost did not arrest the new comers, who passed over their bodies. There were moments when the intrenchment seemed to be carried, for its ridge was crowned by Frank soldiers; but the defenders--independently of those who guarded the _vallum_--had also divided into compact bodies, which, in readiness behind, fell on the assaulting columns when their heads appealed above the ridge. Thus the conflict presented a series of captures and recaptures of the _vallum_, and it appeared as if the same turns of fortune would be repeated as long as the assailants and defenders were able to form bodies of soldiers. Many fell on both sides, for they fought hand to hand. Then it was that Clodoald, who held the smaller _place d'armes_ on the south-west, led forth a thousand men in good order, keeping along the river; he ordered those who occupied the large _place d'armes_ to pass on between him and the _vallum_, and to fall on the assailants in flank. From the right shore the Franks perceived this movement of Clodoald, and hurried towards the island to attack him and support those of their party who were on the left shore. But Clodoald had the start, and advanced by a direct road, whereas the enemy had to make a détour. In a few minutes, therefore, he came upon the body of Franks which, at the instance of Secondinus, was guarding the passage. He attacked it most vigorously, and cut down the first he met with. The Franks resisted, however, and, covering the embankment, formed in a square, with their right against the river. Fresh assailants passed over to the embankment, and took up such a position on the left that Clodoald's troop was on the point of being surrounded, and to free itself was obliged to make a movement in retreat, not without much loss--abandoning the left shore in order to reach the slopes and choose more advantageous ground.