Imatges de pÓgina
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not be modified in their calibre for this purpose, and provided with shells as well as shot.

As to the injury sustained from an enemy's shells, that will undoubtedly be more serious in steamers than in sailing vessels, because, in addition to all the liabilities to injury that belong, inherently, to vessels of all kinds, there are several superadded by the machinery, the wheels, the boilers, &c., of steamers. In contests between vessels, whether sailing or steam vessels, the effects of shellguns will no doubt be very destructive on both sides; but between forts and ships, the peculiar injury inflicted by shells will be suffered by the vessel exclusively. The fort will suffer less from hollow shot than from solid shot. This, though true beyond all question or cavilling, may need a few words of explanation.

How are the batteries to be affected by them? It can be but in two ways: first, the ship's gun having been pointed so as to strike a vital point-that is to say, a gun or a carriage—the shell may explode at the instant of contact. This explosion may possibly happen thus opportunely, but it would happen against all chances; and if happening, would probably do no more than add a few men to the list of killed and wounded. For reasons that will soon appear, it is to be doubted whether the probability of dismounting the gun would be so great as if the missile were a solid thirty-two pound shot. Secondly, if it be not by dismounting the guns or killing the garrison, the effect anticipated from these missiles must result from the injury they do the battery itself. Now we are perfectly informed by military experience as to the effects of these shells upon forts and batteries ; for the shells are not new, although the guns may be so; the eight-inch and the ten-inch shells having always been supplied in abundance to every siege train, and being perfectly understood, both as to their effects and the mode of using them. Were it a thing easily done, the blowing away of the parapets of a work (a very desirable result to the attacking party) would be a common incident in the attacks of fortifications; but the history of attacks by land or water affords no such instance. The only practicable way yet discorered of demolishing a fortification being by attaching a mine to the foot of the wall; or by dint of solid shot and heavy charges fired intermittingly, during a long succession of hours, upon the same part of the wall, in order not only to break through it, but to break through it in such a manner that the weight and pressure of the incumbent mass may throw large portions of the wall prostrate. This, the shortest and best way of breaking a wall, requires, in the first place, perfect accuracy of direction; because the same number of shots that being distributed over the expanse of a wall would merely peel off the face, would, if concentrated in a single deep cut, cause the wall to fall; and it requires, moreover, great power of penetration in the missile—the charge of a breeching gun being, for that reason, one-third greater than the common service charge. Now the requisite precision of firing for this effect is wholly unattainable in vessels, whether shot be solid or hollow; and if it were attainable, hollow shot would be entirely useless for the purpose, because every one of them would break to pieces against the wall, even when fired with a charge much less than the common service charge. This is no newly discovered fact; it is neither new nor doubtful. Every hollow shot thrown against the wall of a fort or battery, if fired with a velocity affording any penetration, will unquestionably be broken into fragments by the shock.

After so much had been erroneously said about the effect of these shells upon the castle of San Juan d'Ulloa, it was deemed advisable, although the result of European experiments were perfectly well known, to repeat, in our own service, some trials touching this point. A target was therefore constructed, having onethird part of the length formed of granite, one-third of bricks, and the remaining third of freestone. This was fired at by a Paixhan gun and by a thirty-two pounder, from the distance of half a mile, and the anticipated results were obtained, namely:

1st. Whether it was the granite, the brick, or the freestone that was struck, the solid thirty-two pound shot penetrated much deeper into the wall, and did much more damage than the eight-inch hollow shot; and, 2d. These last broke against the wall in every instance that the charge of the gun was sufficient to give them any penetration.

The rupture of the shell may often cause the explosion of the powder it contains, because the shell, the burning fuse, and the powder are all crushed up together; but the shell having no penetration, no greater injury will be done to the wall by the explosion than would be caused by the bursting of a shell that had been placed by the hand against it.

From all this it appears incontrovertible that, as regards the effects to be produced upon batteries by ships, solid shot are decidedly preferable to hollow shot; and the ship that, contemplating the destruction of batteries, should change any of her long twenty-four or thirty-two pound guns for Paixhan guns would certainly weaken her armament. Her best missiles, at ordinary distances, are solid shot; and, if she can get near, grape shot to fire into embrasures and over the walls. The best shells against the batteries are the seamortar shells, fired at high elevations; which, being of great weight and falling from a great height, penetrate deeply; and, containing a considerable quantity of powder, cause material ravage by their explosion. Such shells, however, can only be fired by vessels appropriately fitted; namely, by bomb ketches.

The use of these same hollowed shot or shells, by batteries against vessels, is, however, an affair of a different character. The shells do not break against timber; but, penetrating the bulwarks, they, in the first place, would do greater damage than solid shot, by making a large bole and dispersing more splinters; and having, as shot, effected all this injury, they would then augment it many fold by exploding:

In all cases of close action between ship and battery the shells will pass through the nearer side; and, if not arrested by some object on the deck, will probably lodge and explode in the further side, causing by the explosions a much greater loss among the crew, and greater injury to the vessel, than by the mere transit across the vessel; as before suggested, the vessel would suffer less injury were her sides made so thin as not to retain the shell, permitting it to pass through both sides, unless fired with a small velocity. It is not impossible that an extensive use of these horizontal shells may lead to a reduction in the thickness of ship’s bulwarks. It is unquestionably true, therefore, that the advantage of this invention or improvement stands, as between forts and vessels, wholly on the side of fortifications; as between sailing vessels and steamers, it is believed to be, as they are now prepared, on the side of sailing vessels; but this last is a point with which we are not now particularly concerned.

Another invention or improvement of modern days was for a time thought to offer important advantages to vessels in contest with forts; not as making the fort more valuable, but the vessel less so. It was the substitution of iron for wood as the material of vessels' hulls. Experience thus far, however, is unfavorable. To make the sides of a thickness to repel shot demands great cost and involves a material loss of buoyancy, and shot passing through the sides of iron vessels are apt not merely to make a hole of about their diameter, as through wood, but to tear whole plates of iron from their rivets. There is good reason to suppose that the use of this material for war vessels has or will be abandoned; if adhered to, to say the least, it will not lessen the advantages possessed by fortification.

The course of the preceding remarks-in discussing the effects upon sea-coast defence, of numerous railroads, and of the use of steamers as war vessels—led to so many incidental observations on the relative influence of fortifications, that the particular point of this influence has already, perhaps, been sufficiently elucidated. Though the relative superiority of fortifications over any other suggested means has been often enough asserted in these observations, something more must be said as to their sufficiency for the security of the great interests on our coast. If willing to trust for their sufficiency to the example of other nations, we should find abundant proof in the practice of all that have taken part in or been exposed to the hazards of war. All have resorted to fortifications, and many have, for long periods of time, owed to them alone exemption from some of the worst of its calamities. The example of other nations at the present moment, as has before been stated, shows, moreover, that they find no other satisfactory reliance under the increased energy now given to the instruments of warfare than an increase of the number and an augmentation of the force of fortifications.

In opposition to this mode of defence much stress is laid on certain successful attacks that have been made by ships on works deemed strong. I have no doubt that all such results might be accounted for by circumstances independent of the naked question of relative strength, but at any rate, when carefully considered, how little do these results prove in comparison with numerous other instances in which there was an immense disparity of force in favor of vessels that have been signally defeated. These latter instances are those that should be received as a test of the actual relation between the two kinds of force; not certainly because they were successful, but because the smaller the works, its armament, its garrison, the less the probability that any extraneous influence has been in operation. A single gun behind a parapet, provided its position be a fair one and the parapet be proof, need, as regards its contest with ships, owe nothing else to the art of fortification; and its effect will be the same whether the battery were fresh from the hands of the ablest engineer of the age or were erected at the dawn of the art. The gun is in a position to be used with effect; the men are as fully protected by the parapet as the service of the gun will allow; they are brave and skilful, and there is nothing to prevent them from doing their duty to the utmost. These are all conditions easily fulfilled, and therefore likely to be so. The state of things is not less just and fair towards the vessel; she chooses her time and opportunity. The battery goes not to the ship, but the ship to the battery, taking the wind, the tide, the sea-all as she would have them; her condition and discipline are perfect, and her crew courageous and adroit. Nothing, under such circumstances, can prevent the just issue of battle but some extraordinary accident, possible indeed to either party, .but easily recognized when occurring:

The contest between larger works and heary squadrons may be much more complicated affairs; the cause of disaster to the former being often traceable to potent, though not always obvious influences. The fortifications may have been absurdly planned originally, or badly executed, for there has at all times been in this profession, as in others, much scope given to quackery; they may have been erected at a time when ships-of-war, against which they were provided, were very different things from the lofty line-of-battle ships of modern times—a long peace or long impunity may have left them in a state wholly unprepared for the sudden use of their strength; the command may have been intrusted to persons ignorant alike of the amount of power in their hands, and of the mode of exercising it; the garrison may have been undisciplined or mutinous; the populace discontented or disloyal; the clamor of frightened citizens may have caused a premature surrender; all these, or any of them may have produced the issue, leaving the question of relative power untouched.

While there can be no doubt that these and other deteriorating influences may have occasionally operated to the prejudice of fortifications, and that these were likely to be more numerous and more controlling as the works were more exten.sive, it is certain that there can be no influence acting in a reverse direction upon them, that is to say, none making them stronger and more efficient than they ought to be.

There can be no favorable influence of such a nature, for example, as to make the simple one-gun battery, before mentioned, equivalent to a battery (say) ten times as large.

It must not be supposed from what is said in relation to larger fortifications that their magnitude necessarily involves imperfection or weakness, nor because I have considered small and simple works as affording the best solution to the question of relative force must it be inferred that small works are suited to all circumstances. I speak here in reference merely to the judgment we are entitled to form of the relative power of these antagonist forces from their contests as exhibited in history. In instances of the latter sort there cannot, from the nature of the cases, be any important influence operating of which we are ignorant, or for which we cannot make due allowances, while in examples of the former kind we may be in the dark as to many vital matters.

These observations have been deemed necessary because, in judging of this matter, it might not be so obvious that certain brilliant and striking results should not be adopted as affording the true test of relative power. It would be more natural to turn to Copenhagen and Algiers as indicating where the power lies, than to Charleston or Stonington, and yet these latter as indices would be true and the former false.

We will now turn to certain examples.

“The name of Martello tower was adopted in consequence of the good defence made by a small round tower in the Bay of Martello, in Corsica, in the year 1794, which although armed with one heavy gun only, beat off one or two British ships-of-war without sustaining any material injury from their fire. But this circumstance ought merely to have proved the superiority which guns on shore must always in certain situations possess over those of shipping, no matter whether the former are mounted in a tower or not. That this is a just decision will perhaps be readily allowed by all who are acquainted with the following equally remarkable, but less generally known fact, which occurred about twelve years afterward in the same part of the world.

“Sir Sidney Smith, in the Pompée, an eighty-gun ship, the Hydra, of thirty. eight guns, Captain Manby, and another frigate, anchored about eight hundred yards from a battery of two guns situated on the extremity of Cape Lecosa, and protected from assault by a tower in which were five-and-twenty French soldiers, commanded by a lieutenant.

“ The line-of-battle ship and the frigate fired successive broadsides till their ammunition was nearly expended, the battery continually replying with a slow but destructive effect. The Pompie (at which ship alone it directed its fire) had forty shot in her hull, her mizzen topmast carried away, a lieutenant, midshipman, and fireman killed, and thirty men wounded. At length, force proving ineffectual, negotiations were resorted to; and, after some hours parley, the officer, a Corsican and relative of Napoleon, capitulated. It then appeared that the carriage of one of the two guns had failed on the second shot and the gun had subsequently been fired lying on the sill of the embrasure; so that, in fact, the attack of an eighty-gun ship and two frigates had been resisted by a single piece of ordnance."-(Journal of Sieges, by Colonel John T. Jones.)

“ The Corsican tower above mentioned, which had in like manner completely baffled a naval cannonade, was very soon found to surrender when attacked by land; not, however, before a small battery had been made (erected) to reduce it.”—(Paisley's Course, vol. iii.)

Here are two examples : 1st. A single heavy gun mounted on a tower beat off one or two British ships; 2d. A barbette battery, containing two guns, beat off a British eighty-gun ship, supported by two frigates.

It would seem that no exception can possibly be taken to either instance as trials of relative power. There is no complication of circumstances on one side or the other; nothing to confuse or mislead; all is perfectly simple and plain. A small body of artillery judiciously posted on the shore is attacked by armed vessels bearing forty or fifty times as many guns, and the ships, unable to produce any effect of consequence, are beaten off with loss.

The cases present no peculiar advantage on the side of the batteries, either as regards position or quality, for both works were immediately reduced by a land attack—that which the eighty-gun ship and two frigates were unable to effect being immediately accomplished by landing two field-pieces with a very small portion of the crew of one of the vessels. On the other hand, there was no peculiar disadvantage on the part of the ships, as the time and mode of attack were of their own choice.

In order that there might be no unjust disparagement of the vessels in the manner of representing the affairs, the language of British military writers (the ships being British) has been exactly quoted.—(See Paisley's Course of Elementary Fortification, vol. ii, and Journal of Sieges, by Colonel John T. Jones.)

Had the representation of these actions been taken from the victorious party, the result, probably, would have appeared still more to the disadvantage of the ships.

T'he circumstances attending the attack and defence of Copenhagen, in April, 1801, have already been briefly stated. A more minute description will be found in House document No. 206, 1st session, 26th Congress.

I now proceed to examine a great instance of naval success, in which there is no room to doubt the extent to which fortifications were engaged. This instance is the attack on Algiers, in 1816. The attack was made by the combined Eng. lish and Dutch fleets, mounting about one thousand guns, under the command of Lord Exmouth.

In the fortifications that looked towards the water there are enumerated, in a plan supposed to be authentic, three hundred and twenty guns; but not more than two hundred of these could act upon the fleet as it lay. The ratio of the forces engaged, therefore, as expressed by the number of guns, (saying nothing of the calibres, of which we know nothing,) was about as five to two. The action continued from a quarter before three until nine, without intermission, and did not cease altogether until half past eleven.

It is very certain that the effect of the fire upon the Algerine shipping and town was very severe, because we know that all the shipping was destroyed except some small vessels; and we know, also, that Lord Exmouth dictated the the terms of the treaty that followed.

Honorable as this result was to the combined fleets, and happy as it was for the cause of humanity, there are, nevertheless, technical circumstances connected with it that excite doubts as to how much of the final result was due to physical chastisement, to moral effect, to inherent defects in the defences, and to ignorance in the use of these defences, such as they were. That the loss in killed and wounded in the city and works was great is probable, because we are informed that a very great addition had been made to the garrison, in preparation for the attack, under some impression, no doubt, that a landing would be attempted. For the service of the guns there were needed but three or four thousand men at the utmost. An accumulation beyond that number would add nothing to the vigor of defence, while, by causing an increase of the casualties, it would heighten the terrors of the combat. The depressing effect of this loss of life in the batteries and of the burning of buildings within the town and about the mole was, of course, increased by the entire destruction of the Algerine fleet anchored within the mole.

We have no means of judging of the actual condition of the works; nor of their fitness for the task of contending with the heavy ships of modern times.

The forts and batteries on the shore were probably too elevated to be connmanded even by the largest of the sailing ships; and provided these guns were covered with a proof parapet, they may be regarded as being well situated.

But more than half the guns engaged were in the Molehead battery, and the

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