ATTACK OF FORTRESSES.

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breaching, it is necessary to construct the batteries for that purpose in the covert-way, an operation attended with more difficulty, and leading to the artillery being ina more confined position, and more exposed to suffer from shells.

During the time of constructing and obtaining effect from these batteries, thepassages down to and across the ditch are made.

The communications to the ditch may be made either by blowing down the coun-terscarp wail and forming ramps down,—or by galleries from the glacis down to thelevel of the ditch, made on the system explained under the head of * Mines; ; or ifthere are sufficient means and time, both might be adopted,—the galleries for ordinaryservice of the Sappers and progressive work, and the open ramps for storming parties.

Where it is necessary to make lodgements and batteries on the breaches of out-works, the passage across the ditch and up the breach is carried on by Sap, full orflying, according to circumstances.

Though the besiegers are, in these latter operations, advancing in confined spaces,and with narrow fronts and little cover, still their position is so commanding fromthe crest of the glacis, the covert-way, and the outworks,—as in succession they becomepossessed of them, and the garrison of each work attacked consecutively,—so confinedfor space, and either so weak in numbers, or if otherwise, so exposed to the verticalfire, while timely support is so difficult to be given them, that the result is usually aquestion merely of time.

The passages across wet ditches must be made by filling them up for the necessarywidth and height, the rubbish from the breaches and from the communicationsdown to the ditch tending towards them: the rest is either of fascines or earth.

Where there are running streams through a ditch, it will be necessary to leavesufficient openings for the current by a connecting trestle-bridge; or perhaps sidechannels may be possible, to afford another course for the stream.*

According to the ordinary modern system of Attack, it is seldom that any Assaultsare made than the final one for taking the place, but the breaches are successivelyoccupied, and lodgements made on them by the Sap.

The exceptions are, where a work being once taken is irrecoverable, such asenclosed detached redoubts, or outworks, which can be assaulted while their com-munication with the garrison is cut off or rendered too difficult to be re-occupied.

In the first case, the redoubt is, as regards the effects of an Assault, reduced to itsown isolated means ; in the second, the possession of the work will be in the handsof that one of the contending parties which has the easiest communication to it: thusan outwork that is under the fire of the place, and not breached, cannot be held bythe besieger; nor can one that is breached, and without an intrenchment perfectlyclosed against a coup de main, be held by the garrison.

An intrenchment connected with the parapet of a work is no security against anassault, as it will be turned by the parapet, and its garrison driven out with loss.

It does not follow, that because an outwork is taken by assault, that it will con-tinue to be occupied under the fire of the place; the object will be to drive thegarrison in from the immediate propinquity, while the communication to the work,and lodgement on it, shall be made secure.

The final Storming of the Fortress takes place when the breaches are practicable,and there are no obstacles left that can, in the judgment of the besieger, prevent hismasses of troops penetrating completely into the place.

The assembling situations for the storming parties and supports are arranged, and

* Colonel Blanchard’s Infantry Pontoons must now be the resource for crossing wet ditches.— Editors,