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of fortification or defence. We do not easily be finished in the usual manner and time. te to avail ourselves of that suggested by The barbet batteries in the saliants of the demiel Douglas, and which he insists will over- lunes would soon be destroyed and the guns
all the obstacles opposed as well by the dismounted, if not removed upon the completion. ary modes of fortification, as by the new of the batteries 2 and 3, by which the inward od of M. Carnot.
faces of the demi-lunes are ricoched. The faces e ordnance required for the attack shown of the two collateral bastions and their counterate VII. is as follows:
guards would also be ravaged and swept by the batteries 1 and 4; and, if necessary, batteries
might also be placed in the first parallel, to ricob. of Guns. Mortars. Howitzers. Pierriers.
cher the faces of the bastion attacked, and its tery.
counterguard ; but the importance of throwing a more powerful fire upon these works should induce us to reserve this battery for position in the second parallel, satisfied that it may be constructed without establishing more ricochet batteries in the first place of arms. The battery marked in dotted lines in the plan, may, however, be constructed, and should be armed with heavy mortars and howitzers, to fire, at low elevations, to ruin the circular portion of the escarpe-wall opposite to the casemated battery of
the gorge; and to injure or break in the case11
mates. If eight-inch mortars are placed in this battery, they should use, occasionally, sixty
eight pound shot, or shells filled with lead; but 14
heavy iron howitzers, or carronades, will do 15
better : there can be no doubt that with such
means the escarpe-wall and casemates would 60 24 20
sustain very considerable injury.
As soon as the second parallel is completed,
the batteries 5 and 6 are established to ricocher 17
the faces, chemins-des-rondes, ditch, and counter| Brought forward from
guard of the bastion attacked; and the outward 19 the other batteries.
faces of the adjoining demi-lunes with their 20
ditches. The ends of the parallel are secured by
redoubts, armed with field artillery. 22
When batteries 5 and 6 are in activity, the demi-places-d'armes are commenced : they are run out from the flank branches of batteries 5 and 6, until the prolongations of the inward
faces of the demi-lunes are intercepted, and there This proportion of ordnance is about the same the howitzer-batteries 7 and 8 are constructed. that usually estimated for the attack of a front The batteries made in the second parallel, to
Vauban's first system, calculated at the lowest ricocher the faces of the bastion attacked will be ite.
so effectual in ruining their defences, that it does The attack (plate VII.) is made upon a bastion not appear necessary to construct half-parallels nd its collateral demi-lunes.
and howitzer-batteries against them, as has been The first parallel is traced, as usual, about done against the faces of the demi-lunes. 00 toises from the most advanced points of de- The zig-zags upon the capital of the bastion ince, and extended sufficiently to embrace the are pushed forward, from the second parallel, vrolongations of all the works which have in- simultaneously with the construction of the half luence on the attack.
parallels; and, as soon as the batteries 7 and 8 The inward faces of the adjoining bastions, are in activity, the third parallel is commenced, ind their counterguards, are ricoched by the traced, in a right line nearly, joining the three batteries 1 and 4 at the extremities of the saliants of the glacis en contrepente. parallel; and the batteries 2 and 3 are estab- The half-parallels are now extended outwards ished to ricocher the inward faces of the two from batteries 7 and 8 to embrace the prolongademi-lunes and their ditches.
tions of the flanks of the adjoining bastions, and At the same time that these batteries are con- the batteries 11 and 12 there constructed. The structing, approaches are pushed forward on the extremities of the half parallels are connected with three capitals; and the second parallel com- the second parallel by trenches or places of arms, menced as soon as the ricochet batteries, 1, 2, 3, which are thus flanked by the adjoining faces of and 4, are in activity, which should be in thirty- the redoubts, and cover the batteries in the halfsix hours after their commencement.
parallels from being turned by sorties. At the M. Carnot despises so completely all the same time that this is doing, the howitzer-batteries early operations of attack, that we may presume 9 and 10 are established in the third parallel, to upon being very little opposed in constructing ricocher the faces of the bastion attacked, its these works; and consequently that they may ditch and counterguard, if no half-parallel and
howitzer-batteries have been constructed for these on the line of this prolongation, that the cavalier purposes.
may be seen at the point marked by the right of The objects of the mortar-howitzer-battery, battery number 13; and terms taken from No. 15, are to endeavour to ruin as much as the respective commands and distances of the possible the escarpe-wall of the bastion, and retrenchment and other works on the line of the casemated batteries; also to ricocher, and its prolongation show that it may be seen at shell, the communications, chemins-des-rondes, the places marked for batteries 13 and 14 and retranchement générale.
and consequently that it may be ricoched in. An attentive inspection of the plate will both directions. The prolongations of the reshow, that the besieged must suffer greatly from trenchment are obtained, as the plate will show, this battery, particularly at that advanced period clear of the cavaliers; for the command of these of the siege which will oblige them to keep their works is such as to cover batteries 13 and defences manned: for the entrances to the 14 from all the intercepted portions of the chemins-des-rondes of the bastion being in its retrenchment. It is only therefore from the parts gorge at the base of the interior slope, the troops most remote to the bastion attacked, that these entering and returning will be continually pass- batteries can be seen, and that very obliquely :ing, close to the back-wall of the detached case- they cannot be counterbattered. Thus the pormates which flank the ditch, in directions pa- tion of the retrenchment from which battery rallel to the capital of the work, ard consequently 13 may be seen, would be ravaged by the exposed to ricochet fire from battery No. 15; alternate ricochet battery 14; and the part and the ramp leading to the interior of the bas- affecting it, be ricoched by battery 13. The tion, being constructed exactly upon its capital, apparent exposure of batteries 13 and 14 to will be much ravaged by the continual ricochets several stages of fire, renders it necessary to fired in that direction. The seven casemates à notice these circumstances, in order to meet pierriers being open at the ends, all well directed here any observation that might occur as to difshot or shells which do not pass more than fif- ficulty in constructing and using these batteries. teen feet over the top of the escarpe-wall, will The nature of the polygon affects some of these either enter a casemate, or, striking the piers, or circumstances, and would require some modifithe ends of the arches, knock off splinters of cation in the plan of attack; but we must constones that cannot fail to commit great destruc- fine our reasoning to the case before us. The tion among the troops lining the wall immedi- batteries 13 and 14 are connected, by trenches, ately in front.
with the couronnement of the glacis, and armed Nor will the battery itself remain in a perfect with five twenty-four pounders each. state to this period of the siege. It is not too The trenches, saps, and parallels, should be much to expect that eight heavy mortars, or defiladed from the fire of the place, by making howitzers, in action since the opening of the bat- their terrepleins parallel to the plane in which teries, will have done very material damage to the crests of the enemy's works, and the bethe escarpe-wall by which the ends of the case- sieger's trenches lie, so that the lines of direct mates are covered; and it is evident that, where fire, passing close over the parapets of the ever a breach or fracture is made in it, the inte- trenches, parallel to the plane of their interior rior of the adjoining casemate will be completely spaces, do not command them any more than if exposed to direct fire, whenever a lodgment on both were in the same horizontal plane. This the saliant of the bastion is established: and it only requires the additional labor of taking out should be remarked that the escarpe-wall is only the prism of earth necessary to slope the bottom four feet six inches thick, in the recesses made of the trench in a plane parallel to that of the for receiving troops.
command (which, in the present case, is very As soon as the third parallel is finished, trifling), and to make the parapets of the batte lodgments should be made on the crest of the ries a little higher than usual. If this be careglacis, by saps branching outwards from the three fully executed, it will effectually cancel the adcapitals, in circular directions round the saliants, vantages which M. Carnot dwells so much upon, and thence parallel to the edge of the glacis; as arising from this effect of command. constructing traverses and parades wherever it We are now come to that part of the operamay be necessary to defilade the interior of the tion at which M. Carnot says the besiegers will trenches from any of the works of the place. find themselves exposed to the full effect of
Double-saps are pushed forward at the same sorties. time from the third parallel, and an advanced Before parallels were introduced, sorties, it parallel worked right and left to join the lodg- appears, were very generally successful. This ments, or couronnement, of the glacis.
has furnished M. Carnot with many facts calAt the same time that these works are culated to show the good effect of these entercommenced, trenches are worked from the prises of valor before the science of attack re half-parallels near batteries 11 and 12, to ceived its vast improvement from the experience obtain prolongations upon which to construct of its great master, Vauban; and there is no the batteries 13 and 14, which have very want of examples to show that sorties may always important objects to accomplish, viz. to ri- be made with success from places attacked with cocher the faces of the cavaliers, and the re- insufficient force. But if approaches and batte tranchement général. It appears by measure- ries be well protected by parallels, and these ment and calculation obtained from the difference intrenched positions be properly occupied, vigiof commard of the cavalier and demi-lune, lantly guarded, and gallantly defended, sorties together with the distance between their sections will be so severely punished, whatever degree of
temporary, transient succes may attend them, plain, unbroken capacity, as to suffer dreadfully that, perhaps, a siege cannot commence with a from the very nature of fire which M. Carnot circumstance more auspicious to the besiegers, had intended only to infiict. than that of meeting an attack of this nature with When a garrison is so numerous, or when the proper means and prudent dispositions. The besieging force is so inadequate to the enterprise, experience gained during the wars of Louis as to justify the measure of making sorties in XIV., in which the science of attack was force, there is no difficulty in filing out troops perfected to its present state, and the opinion for this purpose through the numerous debouches of all the great military authorities, of which that provided in an ordinary covered-way. If a age was so prolific, are condensed in the maxims sortie is to be made against the second parallel, and instruction given in the eighth volume of the the troops and workmen composing the mainMilitary History of that period, by the marquis body, move out in eight columns (immediately de Quincy, who observes, “Sorties are dangerous afterwards formed into four), from eight different enterprises when the attacks are supported by outlets in the four re-entering places of arms, parallels; and generally produce little advan- each passage admitting easily four men abreasi, tage, and always sustain great loss. We are and consequently of the transit of 320 men per often tempted to estimate the character of a de- minute, if moving at the rate of eighty paces of fence by the sorties d'éclat made during the thirty inches each in that time. Two flanking parsiege; but these contribute more to the reputa- ties to cover the operation move out, each in two tion of the governor for gallantry, than to the columns, from the passages in the more remote advantage of the prince ; since it is certain that places of arins of the adjoining fronts. These any retardation they may occasion to the enemy, debouches altogether admit of filing out, and bears no comparison to the loss which the be- forming in line at the foot of the glacis, a body sieged always sustain on such occasions. Similar of 2560 men, exclusive of the flanking parties, opinions may be traced in every work of charac- in about seven minutes; and the time required ter that has been written upon this subject, from for this operation may be shortened by placing a the date of the authorities just mentioned, to the number of step-ladders to mount over the paliadmirable record of our practice, which, together sades in the three saliant places of arms of the with corrective observations for future guidance, front attacked. If a sortie is to be made against lieutenant colonel Jones has given in his Journal the third parallel, eight or ten step-ladders should of Sieges. If the example set by the publica- be placed in each of the three saliant places of tion of that work be followed by officers who arms, and the eight communications from the may be charged with similar duties hereafter, we four re-entering places of arms used besides. may reasonably hope that the British service will It does not appear then that there is any such not always remain dependent on foreign works difficulty in filing out troops for sorties from exor systems for its guidance
isting places, as should induce us on this account Now if it appear that the attack marked upon to abandon obstacles which are absolutely nethe plan, be as well supported and covered by cessary to prevent the besiegers from easily getplaces of arms; as little exposed to be taken in ting in. The new system of glacis coupés may Alank; in short, as capable of opposing and de- be calculated to admit some brilliant, though feating sorties as that disposition of parallels, generally rash exploits, from a place provided trenches, &c., upon which the opinions and max- with a numerous garrison, or attacked with inims just mentioned have been formed, then it only sufficient means; but it will prove most alarmingly remains for us to consider, whether the facilities defective when the places to which such works which M. Carnot has contrived for bringing out may be added come to fulfill the true purpose his troops shonld overturn what has been so for which fortifications are erected to enable a generally experienced, and taught, as to the or- small force to oppose seven or eight times their dinary failure, and disadvantageons results of number. When this occurs, the very facilities such enterprises—a question which resolves itself of egress, which under such circumstances the into this : Whether the expediency of making the besieged cannot use, will give facility of insorties depends upon the mere convenience, or gress which the besiegers will not fail to avail facility, in bringing out the troops; or, with themselves of; and it appears to me that the whatever ease they may get out, upon the de- purely defensive qualities of these works are so fensive measures and force opposed to them; the defective, that a small garrison, capable enough prospects of success; the consequences of fai- of defending for a time ordinary works of equal lure;- the loss likely to be sustained ;-and the development, would be insecure in this; and circnmstances of the garrison as to being strong that a weak garrison would be utterly incapable enough in force, to afford that loss, and good of defending such a place at all : and perhaps enough in quality, to resist the moral effects of these works are more defective in partial applia defeat, which M. Vauban justly observes is so cation to old systems, than in a full adoption of hurtful to the spirit of the garrison. If these be the whole scheme of defence. the governing considerations which should deter- M. Carnot is so well aware of the impossibility mine the propriety of undertaking sorties, then of defending his glacis coupés de pied-ferme, the accessibility of all M. Carnot's outworks, and and of using vertical fire at the same time, that consequently their exposure to be assaulted when he says these works should not be occupied weakly garrisoned, is a sacrifice made to that on lest the enemy should take them by assault, and, which the issue does not essentially depend, and getting mixed with the troops posted in them, one that would oblige the besieged to keep bodies take prisoners in the mêlée, and thus prevent of troops continually posted in works of such the besieged from firin, upon the assailants. 3600
M. Carnot here again asserts the efficacy of ver. M. Rabenhaupt was detached by the prince of tical fire, to answer this obvious inference that Orange, with about 11,000 inen, to besiege if the counterguard is not occupied, the besiegers Grave, in which there was a garrison of 4000 may easily carry it by assault, and establish men commanded by M. Chamily, an officer themselves upon it. He says that this cannot be already distinguished by his conduct at Candia done, on account, chiefly, of vertical fire; but and in Portugal. we have shown that if he resorts to this mode of The investing force required to attack a place defence, he cannot occupy the escarpe-wall or such as Grave, containing a garrison of 4000 saliant of the bastion either; and if so, the be- men, should not be under 21,000 med, at the siegers may not only take the counterguard, but very least. This is the very lowest calculation proceed, without loss of time, to the attack of that can be made consistently with the number the bastion. We shall here say no more on the of troops required to furnish working parties, subject of sorties, but refer the reader to the plan. guard the trenches, and provide for camp and
All the works—all the exterior debouches and line duties. ditches from which sorties can proceed, are, at The force required for guarding the trenches this stage of the siege, under all sorts of fire. should not be less than three-fourths of the The passages between the ends of the demi-lunes strength of the garrison, and unless this be oband the faces of the counterguards are enfi- served the works of attack will be continually laded and flanked from the different lodgments exposed to interruption, and perhaps to destrucon the saliants of the glacis. The flanks of the tion, by sorties. Now, what sufficient approattack are well secured against sorties from the priation of force to these several duties could adjoining fronts. The second parallel is ap- M. Rabenhaupt have made with 11,000 men ? puyed upon redoubts, and covered from being The proportion required for line, camp, and turned, by being outtlanked by the first place of other duties, is generally rated at, and cannot aring. The third parallel is connected with the well be under, one-tenth of the whole. This second hy trenches of defence, or places of arms, taken at three reliefs is . ; 3300 flanked by the adjoining faces of the redoubts. Working parties, at least 1200 men, The couronnement of the glacis is also covered taken at three reliefs, is . .. in flank by the places of arms connecting batteries 11 and 13 at one extremity, and 12
6900 and 14 at the other; and there is absolutely Which taken from . . . . 11,000 nothing in the proposed attack, bearing upon the question of making sorties, that should over- Leaves, for guarding the trenches, &c. . 4100 turn the general principles already established This, taken at three reliefs, only furnishes 1366 hy long experience as the governing considera- men to oppose sorties which, no doubt, were tions which should be consulted, and which it made with 3000 men; and in the above calculahas been shown are not at all connected with any tion no allowance is made for sickness or casualprinciples of construction.
ties, and all the duty taken at three reliefs, which When the couronnement of the glacis is com- no troops could stand but for a very short serpleted, and the counterbatteries established, the vice, in very fine weather. position of the besiegers would be found still It appears, therefore, that M. Rabenhaupt more capable of defeating and punishing the attacked the place with means so insufficient as sorties; for the counter-slope forms a good old- necessarily to expose himself to all that occurred, fashioned glacis to the besieger's trenches on its even had he been opposed to a less enterprising crest, and gives them all the advantages of a officer. This, indeed, is admitted as the cause covered-way and glacis opposed to the place;- of the protracted defence, by the very historian advantages surrendered to them for a very de- who celebrates the event. M. Quincy, in his fective, and, in some cases, dangerous substitu- Histoire Militaire de Louis XIV., vol. i. page tion, which saves the monstrous difficulties 387, says that “from the frequency of the sorties and labor attending the descent into the ditch, it was difficult to pronounce whether M. Rabenand enables the besiegers to cover the passage of haupt was the assailant or the defender; which it from batteries placed on the crest of (to them) showed the general the error he had committed a glacis proper.
in having flattered himself that he could reM. Carnot mentions repeatealy, tne defence duce the place with the small force which had of Grave, in 1674, as a brilliant instance of pro- been given him.' tracted defence arising entirely from the effects M. Carnot is in error as to what he auvances of continual sorties; and supports his opinion respecting there having been no traverses in the of the advantages of a glacis en contrepente by covered-way, or other exterior obstacles at Grace. stating, that the chief cause which contributed The Histoire du Corps Impérial du Génie into the success of those enterprises of active de- forms us, page 114, that M. de Chamilly, cerfence which took place at Grave, was, precisely, tain of being attacked, had perfected all the that the place had nether counterscarp revetment, works—thickened and reveted the parapetstraverses, nor other obstacles in the covered-way;' made bomb-proof magazines under the ramparts and consequently that sorties were made with placed a double row of palisades, barriers, and facility. It is proper therefore that we should traverses, in the covered-way;' and that he oplook narrowly into the circumstances attending posed all sorts of exterior obstacles to the che this siege, to see how far they confirm the theory minemens de l'ennemi.' This differs very matewhich M. Carnot has endeavoured to establish rially from M. Carnot's account. It shows that upon it.
the usual defensive obstacles of a regular coveredway do not prevent active defence by sorties, the trenches and epaulements are made across wben circumstances of relative force and other the ditch. These trenches should be fitted as considerations, justify their being undertaken; places of arms to oppose sorties. The progress and so far are the real circumstances of this of the attack is not marked on the plan, further siege froin holding it up as a splendid example than the occupation of the counterguard and the to show, generally, the vast advantages, and en- passage of the ditch, not to deface the fortififorce the propriety, of making continual sorties, cations. it appears, that the attack was a very condemna A mine will then be made in the saliant of the ble attempt with a force that could not hold out counterguard. If it be countermined, as M. any fair prospect of success. It is well known Carnot suggests, then a war of mines' will that, when the prince of Orange was obliged to ensue; but the result will be, that the saliant of raise the siege of Oudenarde, he marched to the work will be demolished by one, or other, Grave with the Dutch contingent, and that M. or both parties; and thus the main obstacle reChamilly's garrison had been so much reduced moved which M. Carnot admits, page 480, 'is in the sorties it had made, that the place soon so indispensable to cover the escarpe-wall of the surrendered, although its defences were not much bastion. If a war of mines should not be reinjured. The terms granted to the garrison were sorted to, the besiegers should drive a gallery such as were due to brave men who had done perpendicularly through one of the faces of the their duty in chastising, with vigor and spirit, a counterguard, on a level with the ditch, as soon rash attempt made upon their fortress, but who as a lodgment is made on the crest of the work. surrendered to a force which made any further The labor attending this operation is much less resistance vain and hopeless.
than in making the usual galleries of descent We now proceed with the attack. Batteries into a ditch. The length of a gallery through 17 and 18 are constructed to counterbatter the M. Carnot's counterguard is about ten toises : faces of the collateral bastions; 16 and 19, the galleries of descent into the ditch of an oragainst the faces of the bastion attacked : bat. dinary place are about eighteen toises each. teries 20 and 21 counterbatter the acting faces When the counterbatteries and epaulements of the cavaliers, which it must be recollected in the ditches are finished, the position of the have already been ricoched by batteries 13 and besiegers on the crest of the glacis en contre14.
pente would be so formidable, that we do not Without ascribing any superior degree of see how it is possible for the besieged to efficacy to the fire of the batteries by which the make sorties. The only debouches from which faces of the demi-lunes will have been ricoched, they can issue to attack, directly, the works of there can be no doubt that they may easily be the besiegers, are exposed to two double tiers of taken by assault. We have, indeed, the admis- enfilade and flank fire: for batteries 20 and sion of the author for asserting that troops oc- 21 look directly into the spaces between the cupying them would suffer so dreadfully as to be ends of the demi-lunes and the faces of the incapable of defending them. He admits, ex- counterguard ; and the countersloped glacis pressly, page 492, that the demi-lunes are so enables these batteries to fire over the epaulemuch exposed to stones and ricochets, that troops ments in the ditch, and to combine their fire cannot remain in them. The form given to the with that of the troops lodged in these works; cavaliers for the purpose of strengthening their for a shot fired from battery 20 to the bottom saliants, shows that they are designed to prevent of the exterior slope of the cavalier, passes eight lodgments from being established on the demi- feet over the crest of the epaulement. A sortie lunes; but the batteries 13 and 14 counter- issuing from either of these debouches would batter these saliants, whilst 20 and 21 take also be exposed to batteries 16 or 19, and them in flank and in reverse ; and, as the to the epaulements in front of them, as soon command of the cavalier prevents the salients as the enemy's troops appear; so that no sortie of the demi-lunes from being seen from the in- can come forth from these debouches without tercepted parts of the retrenchment and fausse- being exposed to a quadruple line of fire, under braye, we may assert that the besiegers will a continuation of which they would then have a not experience much difficulty in establishing very formidable line of connected places of arms, themselves on the saliants of the demi-lunes, as to attack. shown in plate VII.
The debouches from the other sides of the These lodgments should not be much extended demi-lunes are under fire of the batteries 17 at present; it will be sufficient to occupy the and 18, and the corresponding epaulements saliant of the rampart with a good, solid, lodg- respectively; and the position of the besiegers ment, commanding the interior of the work; opposite to these outlets is no less formidable and particularly observing the spaces between than the other. the ends of counterguards, and the faces of From the counterguard the besiegers proceed the cavaliers, by which only the troops for the into the ditch of the bastion, in which strong retours offensifs can come forth.
epaulements are constructed to cover the passage, It will now be necessary for the besieged to and to oppose sorties from the opposite debouche. show which mode of defence he means to adopt If the saliant of the counterguard has been for the counterguards and bastions ;-whether he destroyed, or even much lowered, the saliant of intends to defend them de pied ferme, or by the escarpe-wall may be wholly or partially vertical fire-both he cannot use. If he prefer breached by the battery 22. If the counthe latter, the besiegers should assault the coun- terguard be entire, the saliant of the escarpeterguard and form a lodgment on it, as soon as wall will be destroyed by mine. M. Carnot