The orders of the governor were peremptory, and about nine o'clock four hundred workmen, and even women, issued by the north gate to raise the earthworks marked out on the ground by the engineer (Fig. 54). This intrenchment consisted of a small ditch with an earthwork surmounted by stakes, rubbish from the demolition of houses in the town, fascines, and barrels filled with earth. On the western side it started from the boulevard at N, and joined the fosse of the curtain at L, leaving a passage of twenty-four feet between its extremity and the ditch. On the eastern side it reached the entrance of the boulevard O, and followed the line O M, with a similar passage at M. At R and P two culverins were mounted, protected by strong gabionades. On the enemy's side an embankment, with platform and gabions, had been raised at S, and the two bombards of the cavalier, B, were mounted on this platform. At T, Messire Charles d'Amboise had placed a culverin, protected by a gabionade.
The bombards of the cavalier B were replaced by three veuglaires to crush the battery S, if the besieged, taking the offensive, endeavoured to seize it.
On the morning of the 20th of September the works of the besieged were almost completed, or at any rate were high enough to present an obstacle to the assailant. The boulevard, E, had been well furnished with fascines and gabions that very night. The bombard, remounted, swept the point C, and the two culverins the exterior. The intrenchment, C D, was strongly occupied by the defenders at the break of day with small cannon and powerful catapults. The barricades on the flanks, V and X, were strengthened. The Sire de Montcler sent two hundred men to the boulevard, E, with orders to keep under cover as far as possible, and to use their weapons only in case of the intrenchment being forced. The attack commenced about six o'clock. The two bombards, S, discharged stone balls on the salient of the intrenchment and on the boulevard; at the same time the two pieces, I and T, directed their fire on the epaulement, C, and the interval, S T, was occupied by arbalisters and men who served the small cannon under cover of mantelets. From the cavalier, A, the bombards continued to discharge balls broadcast on the boulevard E, as on the previous days. From the platform of this cavalier A, Messire Charles d'Amboise had observed the intrenchment which the besieged had raised during the night; he therefore resolved to bring all his efforts to bear on the salient and the boulevard. With this view, about eight o'clock, he brought up two culverins at Y, which, protected by gabions, were also made to do duty. The besieged replied only with their small cannon and the two culverins of the epaulements, C and D, and their arbalisters. They were husbanding their fire for the moment of assault. At noon, the salient of the intrenchment was broken down, and the escarpment of the boulevard was greatly damaged. The defenders were driven from their position at Z; their culverin, C, was dismounted, and the western epaule rendered untenable. They dispersed or took refuge along the intrenchment from Z to D, which was less exposed. The Sire de Montcler gave orders to return within the second intrenchment. They brought away the culverin D, which was mounted at the extremity L; but they were obliged to leave the piece C after having spiked it. As soon as Charles d'Amboise saw the besieged abandon his intrenchment he ceased firing, and, having marshalled an assaulting column furnished with ladders, poles, and cutlasses, ordered it to cross the ruined salient and assault the boulevard without giving the enemy breathing time. This was the moment for which the commandant was waiting. As soon as he saw this column begin to move and pass the intrenchment, he directed upon it a simultaneous fire from the pieces of the two towers G and H, the two culverins mounted on the boulevard, and all the small cannon. The assaulting column, thus taken obliquely and in front, hesitated and fell back; when it was greeted by a shower of crossbow bolts from the ramparts of the boulevard. It rallied, however, behind the battery S, which discharged a volley upon the boulevard, and, turning slightly on its right so as at least to shelter itself from the fire of the tower H, it passed the intrenchment once more and threw its scaling ladders on the escarpment of the boulevard. The defenders sustained the assault resolutely. The tower, G, then began to fire on the assailants as well as the culverins brought up at L and P.