Page:Encyclopædia Britannica, Ninth Edition, v. 9.djvu/493

FORTIFICATION 461 Stolzenberg, and the direction of some others changed, in order to batter the right bastion of Bischopsberg, the fire of which had greatly incommoded the French batteries. During the day of the 2Gth the fire on both sides was exceedingly animated ; but at seven in the evening, that of the garrison suddenly ceased, and a column of 600 Prussian grenadiers, followed by 200 workmen, sallied out of the place. As the sortie had been foreseen, preparations had been made to repulse it. It was attacked in front and on both flanks; the whole column was either killed or taken prisoners. Meanwhile the works were vigorously pushed forward at all points. The batteries of Stolzenberg were united with the attack on the Bischopsberg; emplacements were prepared for batteries a ricochet ; at the attack of the lower Vistula the works were continued, and a tongue of laud situated at the extremity of the isle of Holm taken possession of and isolated by means of a cut, whilst at the principal attack the greatest exertions were made to prolong the right of the third parallel, and enlarge the communications. On the 30th April the batteries of the besiegers, augmented by several pieces which had arrived from Warsaw, thundered on the place, in different quarters of which conflagrations appeared ; and the besieged replied by the lire of all the batteries of the front attacked, directing more than thirty pieces on a redoubt which fired with the greatest effect. But as the fire of the besiegers had made little impression on the ex terior fortifications, which were of earth, it was during the first days of May directed chiefly against the palisades, and the utmost acti vity was at the same time evinced in extending, improving, and urging forward the attack ; whilst, on the other hand, the garrison showed equal vigour in obstructing the approaches and destroying the works of the besiegers. In fact, notwithstanding the address of the French artillery, that of the garrison still remained effective, because it had not been possible to ricochet the lines of the fortifi cations, and the resources of the besieged in munitions of all kinds were more considerable than those of the besiegers. On the urgent recommendation of General Chasseloup, who had by this time assumed the direction of the attack, it was decided that the isle of Holm should be assaulted, as the possession of it would enable the besiegers to take in reverse the front attacked. The be sieged had spared no pains for the preservation of this important post, from a redoubt on which, called Kalke Schauze, they had con tinually annoyed the left flank of the trenches. In the night of the 6th and 7th of May, however, it was attacked, and carried after a desperate resistance, whilst the possession of it was secured by works added to the intrenchments which had just been stormed, and its batteries were turned against the place. At the principal attack the fire of the besiegers had also mastered that of the besieged ; and Marshal Lefebvre was preparing to assault the fort of Hagelsberg, when on the 12th a Russian corps d armee of 18,000 men, under the command of General Kamwnskoi arrived by sea, and disembarked at the intrenched camp of Neufahrwasser. At the moment of landing his troops, General Kamenskoi was ignorant of the capture of the isle of Holm, and he was disconcerted to find such an obstacle to his communications with the place. This occasioned delay which proved fatal to his enterprise ; for had he attacked immediately on landing, it is not improbable that he would have succeeded. It was only on the 15th of May, however, the third day after the disembarkation, that he made an attempt to succour the besieged city. He began to debouch at four in the morning, and, under cover of a brisk cannonade, formed his force, consisting of 12,000 men, in four columns of attack. The onset was impetuous, and at first the Russians gained ground ; but they were ultimately repulsed at all points, and forced to retreat with great loss to the intrenched camp. Field-marshal Kalkreuth made no attempt to second this attack by a general sortie, which would have placed the French between two fires ; and by its failure the fate of Dantzie was decided. The works of the besiegers were now pushed forward with re doubled vigour ; and the following day preparations were made for the assault of Hagelsberg. Foreseeing this, Marshal Kalkreuth resolved to make a last effort to destroy the nearest works of the besiegers, and for this purpose ordered a grand sortie, which took place on the evening of the 20th May ; but although the Prussians fought with all the fury of despair, they were driven back, and pursued into the ditch of the place. On the 21st the besieging army was reinforced by the arrival of the troops of Marshal Mortier, part of which had remained before Colberg ; the marshal himself quickly followed ; and orders were immediately issued for the assault of Hagelsberg. Before giving the signal, however, Marshal Lefebvre again summoned the governor of Dantzic, who, having no longer hope of succour, and being convinced that the besiegers were in a condition to make themselves masters of the fort of Hagelsberg, showed a disposition to capitulate. A suspension of arms was accordingly agreed to, and this was followed, on the 24th of May, by a capitulation, the principal conditions of which were similar to those which the field-marshal himself had granted to the garrison of Mayencc in 1793. 1 1 See Dumas, Precis des fivenemens Militaires, torn, xviii. p. 123. These two sieges illustrate so well the principles of attack and defence, and are so perfect of their kind, that it has not been thought worth while to add an example of a more recent siege; but it should be observed that in future the preliminary operations of the besieger must take place at far greater distances ; he will break ground for his first parallel at not less than twice the distance hitherto laid down, and will place his first batteries in rear of the parallel. This, while entailing on him much greater labour in parallels, trenches, and approaches, offers counter balancing advantages, as it allows him to disperse his bat teries in small units without the sacrifice of any of their power of simultaneous concentration on the point of attack, and with diminished exposure to the counterblows of the enemy s artillery. BASTIONED SYSTEMS OF THE NETHERLANDS. The Bastioned System of the Italians was carried into other countries by their engineers, who were extensively engaged in the service of foreign princes, and the celebrated Italian engineer Marchi, coming to Brussels with Margaret of Austria in 1559, appears^to have introduced the Bastioned System into the Netherlands. It has been shown that in permanent defences, the ordinary earthen scarp adopted in ditches of field works had been replaced by a masonry revet ment as a security against surprise, in consequence of which, in old Italian fortresses, lofty revetments were almost uni versal ; but in a country the soil of which is permeated by water within a few feet of the surface, such a mode of guarding against escalade would have been enormously ex pensive, and the alternative was adopted of forming broad wet ditches round the ramparts, and by thus securing them from sudden attack, revetment became unnecessary. The first example of a fortress surrounded by simple earthen ram parts without revetments is said to be that of Breda, for tified in 1553 by Count Henry of Nassau, and this arrange ment required only to be moulded into the bastioned trace to constitute the ancient system of the Netherlands, as described by Freitag in 1630. Freitag made the flanks of his bastions perpendicular to the curtain, the faces 98 yards long, with a flanked angle not exceeding 90, and the length of the curtain 149 yards. Freitag had strange notions respecting his profiles, regu lating the height and thickness of his ramparts not so much by the resistance they were required to offer to artillery as by the number of sides of his polygon ; but disregarding these vagaries of the systematist, the annexed cut (fig. 68) Fig. 68. may be assumed to represent the profile usually adopted by the Dutch engineers, R being the body of the place, F the fausse-braye, D the ditch. It will be observed that the main rampart is surrounded by an advanced parapet called a fausse-braye. This ad vanced parapet was intended to deliver a grazing fire on the ditch, whilst the space between it and the rampart formed a spacious chemin des rondes for the assemblage and move ment of troops"; but great as these ^advantages are, the fausse-braye has dropped into disuse. It is not possible to remain in it under a heavy vertical fire, the shells either dropping directly, or rolling down into it from the slope of the rampart above. Such shell trajis, as they are called, are scrupulously avoided by modern engineers, who know that the improvement of vertical fire will ere long add materially to the difficulties of defence. In the bombard ment of Sweaborg, an illustration was afforded of what may be expected of heavy mortars, when the shell becomes a