The attack (plate VII.) is made upon a bastion and its collateral demi-lunes.

The first parallel is traced, as usual, about 300 toises from the most advanced points of defence, and extended sufficiently to embrace the prolongations of all the works which have influence on the attack.

The inward faces of the adjoining bastions, and their counterguards, are ricoched by the batteries 1 and 4 at the extremities of the parallel; and the batteries 2 and 3 are established to ricocher the inward faces of the two demi-lunes and their ditches.

At the same time that these batteries are constructing, approaches are pushed forward on the three capitals; and the second parallel commenced as soon as the ricochet batteries, 1, 2, 3, and 4, are in activity, which should be in thirtysix hours after their commencement.

M. Carnot despises so completely all the early operations of attack, that we may presume upon being very little opposed in constructing these works; and consequently that they may

easily be finished in the usual manner and time. The barbet batteries in the saliants of the demilunes would soon be destroyed and the guns dismounted, if not removed upon the completion of the batteries 2 and 3, by which the inward faces of the demi-lunes are ricoched. The faces of the two collateral bastions and their counterguards 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 ricocher the faces of the bastion attacked, and its 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 casemates. If eight-inch mortars are placed in this battery, they should use, occasionally, sixtyeight pound shot, or shells filled with lead; but heavy iron howitzers, or carronades, will do better there can be no doubt that with such means the escarpe-wall and casemates would sustain very considerable injury.

As soon as the second parallel is completed, the batteries 5 and 6 are established to ricocher the faces, chemins-des-rondes, ditch, and counterguard of the bastion attacked; and the outward faces of the adjoining demi-lunes with their ditches. The ends of the parallel are secured by redoubts, armed with field artillery.

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 the howitzer-batteries 7 and 8 are constructed.

The batteries made in the second parallel, to ricocher the faces of the bastion attacked will be so effectual in ruining their defences, that it does not appear necessary to construct half-parallels and howitzer-batteries against them, as has been done against the faces of the demi-lunes.

The zig-zags upon the capital of the bastion are pushed forward, from the second parallel, simultaneously with the construction of the half parallels; and, as soon as the batteries 7 and 8 are in activity, the third parallel is commenced, traced, in a right line nearly, joining the three saliants of the glacis en contrepente.

The half-parallels are now extended outwards from batteries 7 and 8 to embrace the prolongations of the flanks of the adjoining bastions, and the batteries 11 and 12 there constructed. The extremities of the half parallels are connected with the second parallel by trenches or places of arms, which are thus flanked by the adjoining faces of the redoubts, and cover the batteries in the halfparallels from being turned by sorties. At the same time that this is doing, the howitzer batteries 9 and 10 are established in the third parallel, to ricocher the faces of the bastion attacked, its ditch and counterguard, if no half-parallel and

howitzer-batteries have been constructed for these

purposes.

The objects of the mortar-howitzer-battery, No. 15, are to endeavour to ruin as much as possible the escarpe-wall of the bastion, and the casemated batteries; also to ricocher, and shell, the communications, chemins-des-rondes, and retranchement générale.

An attentive inspection of the plate will show, that the besieged must suffer greatly from this battery, particularly at that advanced period of the siege which will oblige them to keep their defences manned: for the entrances to the chemins-des-rondes of the bastion being in its gorge at the base of the interior slope, the troops entering and returning will be continually passing, close to the back-wall of the detached casemates which flank the ditch, in directions parallel to the capital of the work, ard consequently exposed to ricochet fire from battery No. 15; and the ramp leading to the interior of the bastion, being constructed exactly upon its capital, will be much ravaged by the continual ricochets fired in that direction. The seven casemates à pierriers being open at the ends, all well directed shot or shells which do not pass more than fifteen feet over the top of the escarpe-wall, will either enter a casemate, or, striking the piers, or the ends of the arches, knock off splinters of stones that cannot fail to commit great destruction among the troops lining the wall immediately in front.

Nor will the battery itself remain in a perfect state to this period of the siege. It is not too much to expect that eight heavy mortars, or howitzers, in action since the opening of the batteries, will have done very material damage to the escarpe-wall by which the ends of the casemates are covered; and it is evident that, whereever a breach or fracture is made in it, the interior of the adjoining casemate will be completely exposed to direct fire, whenever a lodgment on the saliant of the bastion is established: and it should be remarked that the escarpe-wall is only four feet six inches thick, in the recesses made for receiving troops.

As soon as the third parallel is finished, lodgments should be made on the crest of the glacis, by saps branching outwards from the three capitals, in circular directions round the saliants, and thence parallel to the edge of the glacis; constructing traverses and parades wherever it may be necessary to defilade the interior of the trenches from any of the works of the place.

Double-saps are pushed forward at the same time from the third parallel, and an advanced parallel worked right and left to join the lodgments, or couronnement, of the glacis.

At the same time that these works are commenced, trenches are worked from the half-parallels near batteries 11 and 12, to obtain prolongations upon which to construct the batteries 13 and 14, which have very important objects to accomplish, viz. to ricocher the faces of the cavaliers, and the retranchement général. It appears by measurement and calculation obtained from the difference of command of the cavalier and demi-lune, together with the distance between their sections

on the line of this prolongation, that the cavalier may be seen at the point marked by the right of battery number 13; and terms taken from the respective commands and distances of the retrenchment and other works on the line of its prolongation show that it may be seen at the places marked for batteries 13 and 14 and consequently that it may be ricoched in both directions. The prolongations of the retrenchment are obtained, as the plate will show, clear of the cavaliers; for the command of these works is such as to cover batteries 13 and 14 from all the intercepted portions of the retrenchment. It is only therefore from the parts most remote to the bastion attacked, that these batteries can be seen, and that very obliquely :they cannot be counterbattered. Thus the portion of the retrenchment from which battery 13 may be seen, would be ravaged by the alternate ricochet battery 14; and the part affecting it, be ricoched by battery 13. The apparent exposure of batteries 13 and 14 to several stages of fire, renders it necessary to notice these circumstances, in order to meet here any observation that might occur as to dif ficulty in constructing and using these batteries. The nature of the polygon affects some of these circumstances, and would require some modification in the plan of attack; but we must confine our reasoning to the case before us. The batteries 13 and 14 are connected, by trenches, with the couronnement of the glacis, and armed with five twenty-four pounders each.

The trenches, saps, and parallels, should be defiladed from the fire of the place, by making their terrepleins parallel to the plane in which the crests of the enemy's works, and the besieger's trenches lie, so that the lines of direct fire, passing close over the parapets of the trenches, parallel to the plane of their interior spaces, do not command them any more than if both were in the same horizontal plane. This only requires the additional labor of taking out the prism of earth necessary to slope the bottom of the trench in a plane parallel to that of the command (which, in the present case, is very trifling), and to make the parapets of the batteries a little higher than usual. If this be carefully executed, it will effectually cancel the advantages which M. Carnot dwells so much upon, as arising from this effect of command.

We are now come to that part of the operation at which M. Carnot says the besiegers will find themselves exposed to the full effect of sorties.

Before parallels were introduced, sorties, it appears, were very generally successful. This has furnished M. Carnot with many facts calculated to show the good effect of these enterprises of valor before the science of attack received its vast improvement from the experience of its great master, Vauban; and there is no want of examples to show that sorties may always be made with success from places attacked with insufficient force. But if approaches and batteries be well protected by parallels, and thes intrenched positions be properly occupied, vigilantly guarded, and gallantly defended, sorties will be so severely punished, whatever degree of

temporary, transient success may attend them, that, perhaps, a siege cannot commence with a circumstance more auspicious to the besiegers, than that of meeting an attack of this nature with proper means and prudent dispositions. The experience gained during the wars of Louis XIV., in which the science of attack was perfected to its present state; and the opinion of all the great military authorities, of which that age was so prolific, are condensed in the maxims and instruction given in the eighth volume of the Military History of that period, by the marquis de Quincy, who observes, Sorties are dangerous enterprises when the attacks are supported by parallels; and generally produce little advantage, and always sustain great loss. We are often tempted to estimate the character of a defence by the sorties d'éclat made during the siege; but these contribute more to the reputation of the governor for gallantry, than to the advantage of the prince; since it is certain that any retardation they may occasion to the enemy, bears no comparison to the loss which the besieged always sustain on such occasions.' Similar opinions may be traced in every work of character that has been written upon this subject, from the date of the authorities just mentioned, to the admirable record of our practice, which, together with corrective observations for future guidance, lieutenant colonel Jones has given in his Journal of Sieges. If the example set by the publication of that work be followed by officers who may be charged with similar duties hereafter, we may reasonably hope that the British service will not always remain dependent on foreign works or systems for its guidance

Now if it appear that the attack marked upon the plan, be as well supported and covered by places of arms; as little exposed to be taken in flank; in short, as capable of opposing and defeating sorties as that disposition of parallels, trenches, &c., upon which the opinions and maxims just mentioned have been formed, then it only remains for us to consider, whether the facilities which M. Carnot has contrived for bringing out his troops should overturn what has been so generally experienced, and taught, as to the ordinary failure, and disadvantageous results of such enterprises-a question which resolves itself into this: Whether the expediency of making sorties depends upon the mere convenience, or facility, in bringing out the troops; or, with whatever ease they may get out, upon the defensive measures and force opposed to them; the prospects of success; the consequences of failure-the loss likely to be sustained;-and the circumstances of the garrison as to being strong enough in force, to afford that loss, and good enough in quality, to resist the moral effects of a defeat, which M. Vauban justly observes is so hurtful to the spirit of the garrison. If these be the governing considerations which should determine the propriety of undertaking sorties, then the accessibility of all M. Carnot's outworks, and consequently their exposure to be assaulted when weakly garrisoned, is a sacrifice made to that on which the issue does not essentially depend, and one that would oblige the besieged to keep bodies of troops continually posted in works of such

plain, unbroken capacity, as to suffer dreadfully from the very nature of fire which M. Carnot had intended only to inflict.

When a garrison is so numerous, or when the besieging force is so inadequate to the enterprise, as to justify the measure of making sorties in force, there is no difficulty in filing out troops for this purpose through the numerous debouches provided in an ordinary covered-way. If a sortie is to be made against the second parallel, the troops and workmen composing the mainbody, move out in eight columns (immediately afterwards formed into four), from eight different outlets in the four re-entering places of arms, each passage admitting easily four men abreast, and consequently of the transit of 320 men per minute, if moving at the rate of eighty paces of thirty inches each in that time. Two flanking parties to cover the operation move out, each in two columns, from the passages in the more remote places of arms of the adjoining fronts. These debouches altogether admit of filing out, and forming in line at the foot of the glacis, a body of 2560 men, exclusive of the flanking parties, in about seven minutes; and the time required for this operation may be shortened by placing a number of step-ladders to mount over the palisades in the three saliant places of arms of the front attacked. If a sortie is to be made against the third parallel, eight or ten step-ladders should be placed in each of the three saliant places of arms, and the eight communications from the four re-entering places of arms used besides.

It does not appear then that there is any such difficulty in filing out troops for sorties from existing places, as should induce us on this account to abandon obstacles which are absolutely necessary to prevent the besiegers from easily getting in. The new system of glacis coupés may be calculated to admit some brilliant, though generally rash exploits, from a place provided with a numerous garrison, or attacked with insufficient means; but it will prove most alarmingly defective when the places to which such works may be added come to fulfill the true purpose for which fortifications are erected-to enable a small force to oppose seven or eight times their number. When this occurs, the very facilities of egress, which under such circumstances the the besieged cannot use, will give facility of ingress which the besiegers will not fail to avail themselves of; and it appears to me that the purely defensive qualities of these works are so defective, that a small garrison, capable enough of defending for a time ordinary works of equal development, would be insecure in this; and that a weak garrison would be utterly incapable of defending such a place at all: and perhaps these works are more defective in partial application to old systems, than in a full adoption of the whole scheme of defence.

M. Carnot is so well aware of the impossibility of defending his glacis coupés de pied-ferme, and of using vertical fire at the same time, that he says these works should not be occupied lest the enemy should take them by assault, and, getting mixed with the troops posted in them, take prisoners in the mêlée, and thus prevent the besieged from firing upon the assailants.'

M. Carnot here again asserts the efficacy of vertical fire, to answer this obvious inference-that if the counterguard is not occupied, the besiegers may easily carry it by assault, and establish themselves upon it. He says that this cannot be done, on account, chiefly, of vertical fire; but we have shown that if he resorts to this mode of defence, he cannot occupy the escarpe-wall or saliant of the bastion either; and if so, the besiegers may not only take the counterguard, but proceed, without loss of time, to the attack of the bastion. We shall here say no more on the subject of sorties, but refer the reader to the plan. All the works-all the exterior debouches and ditches from which sorties can proceed, are, at this stage of the siege, under all sorts of fire. The passages between the ends of the demi-lunes and the faces of the counterguards are enfiladed and flanked from the different lodgments on the saliants of the glacis. The flanks of the attack are well secured against sorties from the adjoining fronts. The second parallel is appuyed upon redoubts, and covered from being turned, by being outflanked by the first place of arins. The third parallel is connected with the second by trenches of defence, or places of arms, flanked by the adjoining faces of the redoubts. The couronnement of the glacis is also covered in flank by the places of arms connecting batteries 11 and 13 at one extremity, and 12 and 14 at the other; and there is absolutely nothing in the proposed attack, bearing upon the question of making sorties, that should overturn the general principles already established by long experience as the governing considerations which should be consulted, and which it has been shown are not at all connected with any principles of construction.

When the couronnement of the glacis is completed, and the counterbatteries established, the position of the besiegers would be found still more capable of defeating and punishing the sorties; for the counter-slope forms a good oldfashioned glacis to the besieger's trenches on its crest, and gives them all the advantages of a covered-way and glacis opposed to the place;advantages surrendered to them for a very defective, and, in some cases, dangerous substitution, which saves the monstrous difficulties and labor attending the descent into the ditch, and enables the besiegers to cover the passage of it from batteries placed on the crest of (to them) a glacis proper.

M. Carnot mentions repeatedly, tne defence of Grave, in 1674, as a brilliant instance of protracted defence arising entirely from the effects of continual sorties; and supports his opinion of the advantages of a glacis en contrepente by stating, that the chief cause which contributed to the success of those enterprises of active defence which took place at Grave, was, precisely, that the place had nether counterscarp revetment, traverses, nor other obstacles in the covered-way;' and consequently that sorties were made with facility. It is proper therefore that we should look narrowly into the circumstances attending this slege, to see how far they confirm the theory which M. Carnot has endeavoured to establish upon it.

M. Rabenhaupt was detached by the prince of Orange, with about 11,000 men, to besiege Grave, in which there was a garrison of 4000 men commanded by M. Chamily, an officer already distinguished by his conduct at Candia and in Portugal.

The investing force required to attack a place such as Grave, containing a garrison of 4000 men, should not be under 21,000 men, at the very least. This is the very lowest calculation that can be made consistently with the number of troops required to furnish working parties, guard the trenches, and provide for camp and line duties.

The force required for guarding the trenches should not be less than three-fourths of the strength of the garrison, and unless this be observed the works of attack will be continually exposed to interruption, and perhaps to destruction, by sorties. Now, what sufficient appro priation of force to these several duties could M. Rabenhaupt have made with 11,000 men? The proportion required for line, camp, and other duties, is generally rated at, and cannot well be under, one-tenth of the whole. This taken at three reliefs is Working parties, at least 1200 men, taken at three reliefs, is

Which taken from

3300

3600

6900 11,000

4100

Leaves, for guarding the trenches, &c. . This, taken at three reliefs, only furnishes 1366 men to oppose sorties which, no doubt, were made with 3000 men; and in the above calculation no allowance is made for sickness or casualties, and all the duty taken at three reliefs, which no troops could stand but for a very short setvice, in very fine weather.

It appears, therefore, that M. Rabenhaupt attacked the place with means so insufficient as necessarily to expose himself to all that occurred, even had he been opposed to a less enterprising officer. This, indeed, is admitted as the cause of the protracted defence, by the very historian who celebrates the event. M. Quincy, in his Histoire Militaire de Louis XIV., vol. i. page 387, says that from the frequency of the sorties it was difficult to pronounce whether M. Rabenhaupt was the assailant or the defender; which showed the general the error he had committed in having flattered himself that he could reduce the place with the small force which had been given him.'

M. Carnot is in error as to what he auvances respecting there having been no traverses in the covered-way, or other exterior obstacles at Grave. The Histoire du Corps Impérial du Génie informs us, page 114, that M. de Chamilly, certain of being attacked, had perfected all the works-thickened and reveted the parapetsmade bomb-proof magazines under the ramparts

placed a double row of palisades, barriers, and traverses, in the covered-way;' and that he opposed all sorts of exterior obstacles to the che minemens de l'ennemi.' This differs very materially from M. Carnot's account. It shows that the usual defensive obstacles of a regular covered