At length, on the 20th of February, the batteries of the first parallel, to the number of ten, opened their fire. Each of them was armed with three guns; the first on the right (of the besieger), à ricochet, raked the covered way in front of the right face of the left bastion (of the besieged). The second swept the right face of the left demi-lune; the third, the left face of the middle demi-lune; the fourth, à ricochet, raked the covered way in front of the left face of the left bastion; the fifth swept the salient of the demi-lune; the sixth swept the right face of that demi-lune; the seventh, à ricochet, raked the covered way in front of the left face of the right bastion; the eighth, à ricochet, raked the left face of the demi-lune in the centre; the ninth swept the left face of the right demi-lune; and the tenth, à ricochet, raked the covered way before the left face of the right bastion. Four mortars were mounted between the batteries 4 and 5, 6 and 7. Captain Allaud did not doubt that the principal attack would be directed to the left bastion; he had the gorge of this bastion therefore retrenched during the night. The six twenty-four pounders were placed in battery on the cavaliers of the bastions of the main defence, and well sheltered by traverses and blindages. These six pieces concentrated their fire on the fourth and fifth batteries of the besieger, and succeeded in silencing their fire about noon. Then they fired on battery No. 3, and before night silenced its three guns also. The guns in battery on the cavaliers of the bastions of the work were sufficiently well sheltered not to be in danger from the enemy's projectiles, to which they responded only feebly. But on the night of the 20th February the plans of the besieger had to be modified. At midnight the colonel ordered five hundred men to arm, put horses to his four field-pieces, whose wheels had been covered with rags and wool, and going out by the left demi-lune, he had two pieces placed on the right and two on the left of the road, two hundred yards in front of the glacis, and, on the road itself, the two howitzers, a hundred yards behind. Then he advanced resolutely towards the communicating boyau, between the third and fourth of the enemy's batteries, whose fire had been silenced. The posts offered but a slight resistance; the sappers fled, abandoning the trench, and were pursued to the batteries at the point of the bayonet.
Fig. 70.— The theoretical attack on Vauban's work.
The reinforcements then arrived, and the colonel drew back his men quietly, by echelons, to the guns. These then opened a simultaneous fire on the enemy with grape; and the five hundred men advanced once more, and brought back some prisoners, but seeing themselves again attacked by a superior force, fell back. This time the Germans did not go beyond their trenches, but contented themselves with a few volleys of grape at random. This skirmish did not last more than half an hour. At one o'clock A.M. Captain Allaud placed two hundred workmen at a distance of two hundred and fifty yards in front of the face of the left demi-lune No. 1, crossed by the road, to commence a trench at this point ([Fig. 72]). These workmen were protected by a post of one hundred men, and the two howitzers left on the road. This work consisted of two redans, with massive traverse-shelters (see A). It was sufficiently advanced at daybreak to be able to shelter the workmen. When the enemy, who had begun his work again at the trench boyaux, B and C, in order to commence the second parallel, perceived at early dawn the new work executed by the besieged, he hastened to bring the fire of battery No. 1 upon it, for batteries 2, 3, and 4 had not yet been remounted. But from the cavaliers of the bastions No. I. and V., six guns in two hours silenced this battery, No. 1, in spite of the besieger's batteries, 5 and 6. The day thus passed in cannonading, and the Germans could not continue their boyau of communication, B, which was raked by one of the howitzers which the besieged had placed behind the great traverse of the salient of the redan on the left. They had to modify the direction of the trench, and follow the dotted line, a b.
Fig. 71.— The third parallel and crowning of the covered-way.
