Imatges de pÓgina
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very channel, might be prevented by contrary winds, tides, and other contingencies, from arriving to the assistance and relief of the dock yards."

"Were it to be asked why the sum to be required by these fortifications had not been demanded for strengthening the navy, he would fairly answer that the money which would prove sufficient to accomplish these works would not build so many ships as would serve for the defence of our most valuable harbors. There was, besides, a certain degree beyond which we could neither build nor man any more. The true limit he could not, nor would it be prudent for him to assign, yet in the nature of things such a limit must exist; but there could never be any line drawn to restrain the security which we ought to provide for our dock vards.”

* Vr. Pitt called upon the House to beware how they suffered themselves lightly to be drawn into a line of conduct which might involve their posterity in accumulated evils; and he suggested to their recollection the remorse which they must teel if they should hereafter find that they had, by an ill-timed pertinacity upon the present occasion, brought upon the country calamity and ruin,"

I regret that I have not time to find and adduce a few pertinent facts from the practice of the French nation in this respect, and especially within the last few years. We know well, however, the general result

, namely, that France has always kept herself well guarded by sea-coast fortifications; and, as before said, that she owes her exemption from many heavy calamities to a steady adherence to that policy.

Believing that the statements just presented must conclusively show that nations having experience in war have made fortifications their main reliance for the defence of their ports, reserving their navies for ottensive purposes, and that the greater energy and activity imparted to the latter by modern improvements have compelled a still more powerful preparation of such defences, I turn again to the particular point of our present inquiry, namely, the use and influence of strainers in coast defences. I have to add, that steamers as substitutes for fortifications would be inferior to other armed vessels, because the efficiency of the defence must depend, other things equal, on the number of guns; that is, as a large number will be brought to the attack, a large number must be employed in detence, and steamers carry very few in comparison. The power of rapid locomotion characteristic of steamers, is for this purpose nothing in itself, nor the power of transporting quickly bodies of armed men; there must be the power of heavy and numerous guns, whether moving or anchored. Though very useful in reconnoitring an advancing enemy, in carrying orders, in conveying relief to batteries, in transporting quickly large bodies of men, and in such like duties, steamers could not constitute a good defensive array except against steamers only: and, accordingly, against such an array the enemy's fleet of steamers would bring in tow a few line-of-battle ships or frigates.

Even, therefore, should there be time after a war shall have been opened to prepare in each of the great harbors a hurried display of this kind out of the light river and bay steamers, it would be no match for sea-going steamers and heavy armed vessels brought into the attack; indeed, it would not be

easy to say what excess of numbers, in favor of the defence, could establish an equilibrium. As just said above, there could be no resistance of moment made, except by many heavy guns; and to supply these a great multitude of steamers or of merchant ships would have to be converted into Hoating batteries. What the result of such a resort would be may be learned from the battle of Copenhagen.

This was in no sense a contest between ships and fortifications, as is generally supposed; it was the attack of a fleet of sailing ships upon a line of Hoating batteries of one kind or another. The Danes had anchored on the edge of a shoal a line of these batteries, parallel nearly with the wall of the city, and at the distance of at least three-fourths of a mile. This line could be attacked

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only on the outside, and, when attacked, was interposed between the enemy and the walls, and consequently for the time entirely extinguished the fire from the fortifications.

The line consisted of block-ships and praams—by which are understood to be meant vessels converted into mere floating batteries and more or less strengthened for the purpose; and rafts, supposed to be floats of timber with a timber parapet towards the enemy—in all, eighteen batteries. A squadron of four sails of the line, one frigate and two sloops-of-war, were anchored higher up the harbor—where there was also the “three-crown" battery. Lord Nelson carried to the attack twelve line-of-battle ships, twelve frigates, and a number of smaller armed vessels. All this force he concentrated upon the line of floating batteries; every vessel of which was taken or destroyed, except one or two smaller vessels, which cut their moorings and ran in under shelter of the fortification. This concentration excluded the Danish squadron above mentioned, and also the “three-crown” battery from any material participation in the action. Some English frigates within reach of the latter were greatly injured and obliged to retreat.

This faculty of concentration (applied with success on several memorable occasions by that great naval commander) is an inherent one in an attacking squadron, and is not to be evaded by a line at anchor-especially not by a line of floating batteries.

If, however, we should allow batteries of this sort, whether aided by steam or not-to be equal, gun for gun, to the attacking squadron, and that they can be got ready in time, we nevertheless should thereby throw an enormous expenditure of money upon the country at a moment of great fiscal difficulty. Let us make a rough estimate of that expenditure.

Lord Nelson's fleet, just mentioned, was rated at 1,158 guns, and it is ouly reasonable to assume that we should be liable to a visit from a force as great. Assuming that the merchant vessels taken for conversion into floating batteries, would, on the average, carry ten guns on a broadside, which will be assuming that they are as large as sloops-of-war, we should need fifty-eight such vessels; and estimating these at fifty thousand dollars cach, which, including purchase, armament, alteration, &c., is a moderate allowance, we shall liave a total first cost of two million nine hundred thousand dollars for one port, and for the six ports before mentioned, a grand total of seventeen million four hundred thousand dollars—a sum much greater than has been expended in preparing for more than four thousand of the heaviest guns in permanent fortifications upon the great points of the coast.

If we attempt to supply the requisite force in guns by the use of river and bay steamers, instead of sailing vessels, we cannot allow more than five yuns, in the average, to a broadside; so that we shall require one hundred and sixteen steamers, which, at thirty thousand dollars for purchase, armament and alteration, will give three million four hundred and eighty thousand dollars for the first cost in a single harbor, and for the six ports, twenty million eight hundred and eighty thousand dollars.

I do not give these estimates as exact, though I believe them to be below the cost that would have to be incurred, but as affording hints of the costliness of provisions of that nature. An expenditure for this purpose, equally great,

. would have to be repeated, moreover, at the commencement of every war, or still greater outlays would be incurred in keeping up this perishable armament during peace.

What conclusions follow from the preceding considerations? Why, that in adopting this expedient, we should involve ourselves, at the opening of every war, in a vast outlay for the defence of these ports; that there would be great probability that the preparations, although involving that enormous expense, could not be made in time; that, even if prepared in time, everything would be

rut at the hazard of a single battle, with most important advantages on the side of the enemy, and consequently few probabilities of successful resistance; or if, by more extended preparations, we should endeavor to turn these probabilities the other way, it would be at the greater risk of not being ready, and with the certainty of greatly enhanced cost.

It has been deemed necessary above all things, considering impressions that have been made on the public mind as to the influence of steam vessels upon sea-coast defence. to show at large that while the introduction of the vessels into naval equipment has greatly facilitated attacks, either by steamers alone or in conjunction with sailing vessels, it has done more to avert or repel them, leaving fortifications, which these vessels can in no case replace but at great disadvantage, more indispensable than ever.

In my desire to convey my own strong convictions, I am conscious that I have tediously prolonged this part of the report.

Although what has been said above is undoubtedly true in reference to steamers or other floating defences as substitutes for fortifications, there remain important functions in defence which must be committed to floating defences of some kind, as has before been fully set forth; and in some of these cases it is quite certain that steam batteries may, of all floating defences, be the most suitable.

It must not be forgotten, however, that the very qualities which recommend this particular kind of force will equally characterize the steam vessel of the enemy, and that whether steam vessels or sailing vessels, or both, are relied on, unless there are well-secured points on the shore under which they can take refuge, they will themselves constitute an inviting object to a superior force of

the enemy.

If, for example, we were to deem one of our open waters of such importance as to assign eight or ten steam batteries for its protection, we should thereby place within the reach of the enemy an object worthy of the efforts of a squadron of twelve or fifteen vessels of the same description. Even, therefore, instances where these naval means must be resorted to for defence upon the water, there must be works at hand upon the shore, to the shelter of which, if likely to be overpowered, they can retire.

A branch of the second question, namely, that portion which inquires, “ In what manner recent improvements in artillery and other military inventions and discoveries affect this question,” require some separate remarks.

The only invention and discovery, so far as I am aware, that can affect this question, one way or the other, is that which has introduced the practice of firing shells from guns; and which has involved the use of guns of comparatively large calibre, so that guns which discharge missiles of eight-inch and ten-inch diameter, are rather extensively used, especially eight-inch guns. Even guns of twelve-inch bore have been made in this country, and I believe also in other countries.

It is, of course, understood that even larger shells than these were long ago thrown in the attack and defence of fortified places, from the mortars of land batteries and bomb ketches. The shells now spoken about, instead of being projected under a high angle, as from mortars, are discharged from guns at low angles, or nearly horizontally, like solid shot; these guns of large calibre being often called Paishan guns, after the French officer who first succeeded in securing the favor of the military authorities for the idea—the idea having been suggested long before, and even successfully tried.

These shell.guns are now introduced by maritime nations in all vessels-of-war, whether sailing vessels or steamers. Those latter vessels, which carry but few guns in number, are much augmented in power by their introduction, but not more so than sailing vessels, to which these guns are equally appropriate; and I have no doubt that their numbers will be every day increased, until perhaps there will be few or no armed sailing or steaming ships of which the guns will

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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 shellgins 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 discovered 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 mild, 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 sutriciently elucidated. Though the relative superiority of fortifications over any other

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