Thereupon, trees were felled in the forest on the plateau, and the timberwork of the houses of the lower town brought away. A moat, filled from the river, surrounded the works of the great _tête de pont_; but those of the smaller one no longer possessed any; the fosse had long been filled up, and the besieged had neglected to sink it afresh. The south wall of the _Emporium_, which joined the northern shoulder of that smaller _tête de pont_, was crenelated, and in the hands of the defenders, including the square return on the road coming from the west. Thus half the area of the Emporium was commanded in its length by this wall.[13] Astride on this western road, Secondinus erected an _agger_ which rested against the river, fifty paces from the square return, and on this agger he fixed up a work of framed timber, which commanded the enemy's rampart (Fig. 21). Around the great _tête de pont_, he contented himself with raising a contravallation, which cut off the two roads. Before the eastern gate of the city, the operation presented great difficulties, because of the steepness of the slope of the plateau. Every night, the besiegers' works were thrown down by the defenders, who had the advantage of the dominant position. Secondinus, after several unsuccessful attempts, was obliged to confine himself to forming beneath the ascent of the plateau a work of earth and timber, forming an arc of a circle, as in the accompanying sketch (Fig. 22). The besiegers could reach this work, which was out of range of the plateau, by a road descending gently towards the western arm of the rivulet. These works had not been executed without attempts on the part of the besieged to destroy them, nor without considerable loss on the part of the Franks. A fortnight, however, after the enemy's arrival, they were completed, and strongly guarded. [Illustration: FIG. 21.] The enemy's troops were thus disposed around the cité:--The large encampment on the north plateau was occupied by twelve thousand men; the defenders of the great contravallation on the same side numbered two thousand. The body lodged in the lower town consisted of six thousand men; the guard of the work opposite the small _tête de pont_, five hundred; that of the contravallation around the great _tête de pont_, one thousand two hundred; the work raised at the bottom of the plateau facing the east gate contained one thousand two hundred men. Total: twenty-two thousand nine hundred men. There remained, deducting for losses since the commencement of the siege, about ten thousand soldiers, who scoured and devastated the country, collected provisions and forage, and formed a reserve corps, ready to make a fresh attempt when the propitious moment arrived. [Illustration: FIG. 22.]