Thirteen guns armed the advanced work. The two howitzers were placed in battery, one at the extremity of the salient D, pointed at battery No. 1, the other in the right re-entering _place d'armes_ of the demi-lune No. 1. Two guns were also placed on the right face of the demi-lune; two guns on the front, between the bastions I. and II., and two guns on the right and left faces of this bastion, to sweep the advanced works if they were taken. In all, nineteen guns and two howitzers. Besides, the ridge of the plateau was well defended by a good trench-shelter with traverses, that the work might not be able to be taken by assault in rear by the escarpment. One of the twenty-four pounders was placed in battery in the bastion V. of the main work, in the direction of its capital, to sweep this slope.
On the 25th of February only a few cannon-shots were exchanged. The mortar batteries of the besieger concentrated their fire on the western redan, without doing much damage; but during the night of the 25th the fire of the bombs was so incessant that it became difficult to labour at these works. It continued during the 26th, but the besieged dismounted three of these mortars with the guns left on the bastions II. and III. The besieged on his side placed the two mortars in battery on the front between these two bastions, and sent projectiles into the batteries 11 and 12.
During the 26th of the month (the weather being clear) the enemy was seen to be erecting three batteries on the north-west, evidently directed against the batteries A, B, C, D, to crush them. They could not reply to their fire; the colonel therefore decided that they should bring back into the town temporarily the six guns of the batteries B, C, D. The bombs continued to fall into the works during the whole night of the 26th; and on the morning of the 27th the fire of the three batteries of the enemy, erected six hundred and fifty yards behind the abandoned battery No. 1, was opened against the redans B, C, D; it lasted the whole night of the 27th, damaged the blindages very severely, and threw down the traverses. On the morning of the 28th the _crémaillère_ ceased to be tenable, but the work A had not been seriously injured. The howitzer placed at D had been brought back behind the great traverse F surmounted with a banquette.