When on the previous evening of the 26th the construction of the parallel was sufficiently advanced to allow of its being occupied by larger detachments, the assault was fixed for the 27th. Two columns, each of one battalion, one company of Sappers, and two guns, passed to the attack at daybreak on that morning. Two companies of Schneidemuehl's Landwehr Battalion advanced against the front of Basses Perches and threw themselves on the ground within from 65 to 110 yards of the work. A sub-division of sharp-shooters and a few pioneers reached the ditch and unhesitatingly leaped in; the two other (Landwehr) companies, going round the fort by the left, got into its rear, and here too the men jumped into the ditch of the gorge. But the French who had been driven out of their shelter-trenches were now assembled, and the battalion from Le Fourneau came up. All the forts of the place opened fire on the bare and unprotected space in front of the parallel, and an attempt of reinforcements to cross it failed. The 7th Company of the Landwehr Battalion was surrounded by greatly superior numbers, and after a brave struggle was for the most part made captive. Most of the men in the ditch were still able to escape. The advance of the right column against Hautes-Perches also failed. It had to cross 1100 yards of open ground. The encompassment of the fort was attempted, but it was impossible to force through the abatis and other obstacles under the destructive fire of the enemy. This abortive attempt cost 10 officers and 427 men; and the slower process of an engineer attack had to be resumed. _January 28th to February 15th._--As the approaches to the forts progressed the flying sap could be carried forward about 330 yards every night unopposed by the enemy. In spite of all the difficulties caused by the nature of the soil, on February 1st the second parallel was thrown up at half distance from the Perches. As the Fort of la Justice was a special hindrance to the operations, two new batteries had to be constructed to the east of Perouse against it. Four mortar-batteries on the flanks of the parallel now directed their fire on the Perches at very short range. Three batteries were also constructed in the Bois des Perches to fire on the citadel, and one on the skirt of the wood near Bavilliers against the defences of the city. Henceforward 1500 shells a day were fired on the fortress and its outworks.