Imatges de pÓgina
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gun range from the shores will afford examples of another sort, and harbors with very wide entrances and large surface exhibit examples of still another kind.

As in all such cases fortifications alone will be ineffectual, and nevertheless recourse to defences of some sort may be unavoidable, it has not failed to be a recommendation in the several reports on the defence of the coast since 1818 that there should be a suitable and timely provision of appropriate floating defences. And until the invention of man shall have caused an entire revolution in the nature of maritime attack and defence, these or kindred means must be resorted to, not, however, because they are means intrinsically good or suitable under like circumstances, but because they are the only means applicable to such cases. In the circumstances just referred to there is no alternative, and therefore no point to be discussed. The remaining question is, whether these floating defences are to be relied on in cases that admit of defence by fortifications.

And, first, as to gunboats. Although of undoubted use in peculiar circumstances, it will hardly be contended that gunboats afford a safe reliance in harbors that can be entered by vessels of magnitude. Ships becalmed or aground might be sorely harassed, if not destroyed, by a spirited attack from this force, and there are other situations wherein it would be very effective. But harbors defended by gunboats will not be attacked in calms nor in adverse winds, and it is not easy to believe that any probable array of these crafts would impede or hinder for a moment the advance of a hostile Heet. Nelson, at Trafalgar, bore down in two divisions upon the combined fleet, each division being exposed to a raking fire; and although suffering considerably from that fire, he was able, notwithstanding, to break the hostile line and defeat his superior adversary. What, comparatively, with the raking fire of the combined fleet, would be the fire of a fleet of gunboats ? Opposing no effectual obstacle to approach or entrance, these small vessels, scattered and driven upon the shoals, could be kept by the broadside of a few active vessels at too great a distance to produce any serious effect upon the main attack by their desultory fire.

Although they might afford useful means of annoyance during a protracted occupation by the enemy of harbors containing extensive shoal grounds and shallow bays and inlets, they would be nearly useless in resisting the first assault and in preventing the brief operation of levying contributions, or burning or spoiling national establishments.

The true reason of this defence must not, however, be misunderstood. It is not that the boats do not carry guns enough or men enough for the object, but it is because, from the comparative weakness of the vessels, the guns and the men cannot be kept in an effective position.

There are, moreover, many harbors requiring defence, in which there are no shoals whereon the boats could take refuge; and in such their capture or destruction would be inevitable should there be, at the same time, no river up which they might fly, or lateral issue through which they could escape to a safe distance.

Floating batteries, of which a good use might be sometimes made in peculiar situations, would, I suppose, differ from gunboats, in being larger, containing many guns each, and in being stronger; that is to say, having thicker sides or bulwarks; and it has sometimes even been proposed to construct them with ball-proof parapets, and with platforms open above-like, in these respects, batteries upon the shore. But in whatever way formed, it is necessarily a part of the idea that they be strong and massive ; and, consequently, that they be unwieldy, incapable of sudden change of place, and incapacitated either to advance upon a defeated foe or to evade a victorious one. We are now, of course, speaking of batteries moved by steam, Being denied the power of locomotion, at least for any purpose of maneuvring in face of the enemy, we are to consider these batteries as moored in position, and awaiting his advance. Should the batterries be large, requiring deep water to float them, or should they be placed

across or near the channel, for the sake of proximity to the track of ships, the enemy would engage them at close quarters. All advantages of mobility—of concentrating his whole fleet upon one or two points, to which, under these circumstances, no relief can be sent—of greater elevation and command, would be on the side of the assailant, with no counteracting advantage to the batteries, but greater thickness of bulwarks. Whether this excess of thickness should be considered a material advantage, since the introduction of large bomb-cannon into the armament of ships is a very doubtful matter. The batteries if anchored across the channel would have the further advantage of a raking fire; but we have seen that the raking fire of one squadron of ships upon another advancing is by no means decisive. The power of throwing the whole assailing force upon one or two points, of pouring upon the decks of the batteries a greatly superior force of boarders, would of theinselves seem to leave little room to doubt as to the issue.

If, now, we suppose these floating batteries to be smaller, so that having a lighter draught they might be placed near the shores or upon the shoals, they might certainly be thereby saved from the kind of attack which would prove so fatal if anchored more boldly in deep water; but they would at the same time lose much of their efficiency from their remoteness; and positions wherein they would be secure from being laid alongside, while they would be in a proper attitude to contribute materially to the defence of the harbor, are afforded but rarely. It is doubtful whether, as a general rule, these smaller floating batteries, notwithstanding their greater capacity of endurance, would afford a better defence, gun for gun, than gunboats; or, in other words, whether this capability of endurance in the one would be more than a compensation for the power of locomotion in the other. But whether near the shore or in the channel, whether large or small, this description of defence, owing to its fixedness connected with the destructibility of the material of which it must be made, will be exposed to attacks analogous to those made by gunboats on ships aground. The enemy knowing of what the defensive arrangements consist, will come provided with the requisite number of sailing or steam vessels armed with bomb-cannon, against which the thicker bulwarks of the floating batteries would avail nothing. He would, besides, hardly fail to provide himself with bomb-ketches armed with heavy sea mortars; and as there could be no guarding against the effects of the long ranges of these, a few such vessels would, with great certainty, constrain the floating batteries to quit their position, abandoning every disposition approaching to a concentrated array. Not to mention other modes of attack, which would seem to leave the chances of success with the enemy, it will be noticed that this kind of defence, whether by gunboats or floating batteries, has the same intrinsic fault that an inactive defence by the navy proper has; that is to say, the enemy has it in his power to bring to the attack a force of the same nature and at least as efficacious as that relied on for defence; hence the necessity not of mere quality, but of superiority on the part of the defence at every point liable to be attacked; and hence also the necessity of having an aggregate force as many times larger than that disposable by the enemy, as we have important places to guard. Should we, for example, have ten such places, and the enemy threaten us with twenty ships-of-the-line, we must have, in all these places, an aggregate of gunboats and floating batteries more than equivalent to two hundred ships-of-the-line; for it will hardly be contended that these defences can be transported from one place to another as they may be respectively in danger.

But what will be the relative state of the parties if, instead of gunboats or floating batteries, we resort to steam batteries?

Although much has been said of late of the great advantage that defence is to derive from this description of force, I have not been able to discover the advantages; nor do I see that sea-coast defence has been benefited in any particular

by the recent improvements in steam vessels, except that in the case before adverted to, where from the breadth of the waters defence from the shore would be unavailing, a more active and formidable floating defence than by gunboats and floating batteries is provided.

It must be remembered that by far the greatest improvement in steam vessels consists in having adapted them to ocean navigation; and one inevitable consequence of this improvement will be, that if the defence of harbors by steam batteries be regarded as securing them from the attacks of ships-of-the-line and frigates, or at least of placing the defence quite above that kind of attack, they will no longer be attacked by sailing vessels, but by steam vessels similar in all warlike properties to those relied on for defence.

Not only are there no impediments to transferring these vessels across the ocean, but the rapidity and certainty of these transfers are such as to enjoin a state of the most perfect readiness everywhere and at all times; and also a complete independence of arrangement at each particular point, both the state of preparation and the independence of arrangement being much more important than when the enemy's motions were governed by the uncertain favor of winds and weather.

It is not easy to conceive of any important properties belonging to steam batteries acting defensively, that the attacking steam vessels may not bring with them, or at least may not have imparted to them on their arrival upon the coast, unless it should be thought proper to give to the former a greater thickness of bulwark than would be admissible in sea-going vessels.

But the peculiar advantage conferred by steam lies in the faculty of moving with promptitude and rapidity, and any attempts to strengthen the harbor vessels by thickening their bulwarks considerably would unavoidably lessen their mobility, thereby partially neutralizing the advantage sought. At the same time it is extremely doubtful whether any benefit would be derived from the thicker sides. It is probable that the best kind of bulwarks for these vessels and all others, is that which will be just proof against grape and canister-shot fired from moderate distances, because with such bulwarks a shell fired from a bomb-cannon within a reasonable distance would pierce both sides, that is to say, would go in one side of the ship and out at the opposite side, producing no greater effect than a solid shot of the same calibre, while with thickened sides every shell would lodge in the timbers and produce terrible ravages by bursting.

In the practice with these missiles in this country it has been found difficult to lodge a shell in thin targets, even when the load of the gun was so reduced as to increase materially the uncertainty of aim. As it is probable, therefore, that the protection from solid shot afforded by massive bulwarks would be more than counterbalanced by the greater injury horizontal shells would inflict by means of these bulwarks, we may conclude that the harbor steam battery will not differ in this respect materially from the attacking steamships; and if they do differ in having more solid and impervious bulwarks, that no advantage over the enemy will result therefrom.

We come, therefore, to the same result as when considering the application of the other kinds of floating force to the defence of harbors; and this result is, that there is no way of placing the coast in a condition of reasonable security but by having at any point the enemy may happen to select a force in perfect readiness, which shall be superior to that brought to the attack.

There not only prevails the idea that we ought to rely upon these floating defences, but also the idea that we may postpone the fitting them for service till the commencement of war. Turning again to the six ports before mentioned, our whole peace navy that may happen to be in port and ready for use, being appropriated to local defence in its several stations, immense additions would have to be made at each port; and whether these additions were to be supplied from the ship-yards or by conversion of merchant vessels and service steamers

into floating batteries, a considerable time must necessarily elapse before there could be anything like readiness. In the meantime the enemy, sending a small squadron of war steamers against each—nothing being ready, large squadrons. would not be needed—would nip all preparations in the bud. We have to keep in mind a fundamental principle of this system, which is, not to incur the expense of preparation till the certainty of war has arrived, or, as it might be phrased, till there will no longer be time to prepare.

I should not have gone so much at length into a branch of one subject wherein the general conclusion appears to be so obvious and incontrovertible but for the prevalence of opinions which I consider not erroneous merely, but highly dangerous, and which, I think, must give way before a full exhibition of the truth. I do not anticipate any formidable objections to the positions assumed, nor to the illustrations ; but even should all these, in the form presented, be objected to, I may still challenge opposition to the following broad propositions, namely:

1st. If the sea-coast is to be defended by naval means exclusively, the defensive force at each point deemed worthy of protection must be at least equal in power to the attacking force.

2d. As, from the nature of the case, there can be no reason for expecting an attack on one of these points rather than on another, and no time for transferring our state of preparation from one to another after an attack has been declared, each of them must have assigned to it the requisite means; and,

3d. Consequently, this system demands a power in the defence as many times greater than that in the attack as there are points to be covered.

Believing that a well-digested system of fortification will save the country from the danger attending every form of defence by naval means, and the intolerable expense of a full provision of these means, I will now endeavor to show that such a system is worthy of all reliance.

There has been but one practice among nations as to the defence of ports and harbors, and that has been a resort to fortifications. All the experience that history exhibits is on one side only; it is the opposition of forts or other works comprehended by the term fortification to attacks by vessels; and although history affords some instances wherein this defence has not availed, we see that the resort is still the same. No nation omits covering the exposed points upon her seaboard with fortifications, nor hesitates in confiding in them.

But it has been asserted, in a way to convey incorrect and hurtful impressions. to the country, that fortifications for such purposes are obsolete resorts; that the improvements in the instruments and appliances of war within late years have caused the abandonment of such reliances. This, however, is far from being true; and it is quite important in respect to the quarters whence such assertions have sometimes proceeded not only to sustain, but to enforce this denial.

If considerable additions have not been made lately to the defences of many well-known European harbors, it is because they were fully fortified long ago. And it might here be asked, in passing, what would have happened to the seaports of France during the long wars between her and Great Britain, and with such naval supremacy in the hands of the latter, if the French ports had not. been well fortified? Can it be supposed that anything but these fortifications kept the English out of the great ports and naval depots of France, and permitted large fleets to grow, great expeditions to mature, flotillas to manauvre, under the eyes of the blockading squadron, and almost within reach of its guns?

But it happens that even in well-fortified France any improvement or change in a harbor that affords opportunity and place for new defences is sure to produce them; the Cherbourg breakwater, a work of late years, is supplied with formidable batteries, perhaps even now not quite finished.

It happens, moreover, that in Great Britain, which of all the nations of the earth has most reason to rely for defence on naval power, fortifications are the reliance for harbor defence, and of late years particularly.

The application of steam to ocean navigation has done much, and is likely to do more, to lessen the naval ascendency of that power, and the ports which formerly found security in rather indifferent fortifications under the overwhelming numbers of her men-of-war, have, in the present liability to be surprised by fleets of war steamers, received and are at this moment receiving large additions of strength in forts and batteries, and new “harbors of refuge” are being formed and strongly fortified, in order the better to protect her coast and her commerce under this change of naval relations.

Great Britain sees that she cannot effectually guard her coast and her ports from this particular danger by the number of her war vessels, great as this number is, and greatly as it may be augmented from her vast commercial marine. She does not run into the folly of posting at every dock yard a squadron of steamers as large as any that can be brought against it; but she improves and adds to her old fortifications to make them adequate of themselves, and she creates new (artificial) harbors for the sake of having fortified shelter near the probable field of activity of her navy in its various forms.

Instead, therefore, of lessening the utility of fortifications, we see that, in the opinion of the high military authorities of that government, the late changes and improvements have made the increase and improvement of fortifications indispensable. There are some particulars of her late course in this respect.

Referring to parliamentary estimates for 1847–48, 1848–49, and 1849-'50, I find that for fortification alone, including new works and repairs of old works upon the coast of Great Britain and Ireland, (chiefly along the English channel.) and excluding estimates for barracks, quarters, storehouses, fr., there was demanded for those years, severally, $578,766, $282,892, and $439,036, being $1,300,694 for the last three years.

I find that important colonial ports have received accessions of strength in the same way lately, and that, for example, on the water front of the redoubtable Gibraltar the same batteries that repelled and destroyed the formidable floating batteries of France and Spain in 1782, expenditures exceeding six hundred thousand dollars have been made within four or five years, and $367,887 more are estimated to be necessary to put them in equilibrium with new means of attack.

At Malta, already possessed of very strong fortifications, about $180,000 have already been voted, and $696,000 is called for in addition, to be applied to harbor defences particularly.

The same nation is meanwhile placing in her new coast batteries eight-inch and fifty-six pounders, and thirty-two pound guns; and, at a great expense, is substituting this heaviest kind of ordnance for twenty-four pounders and eighteen pounders in the old batteries. Between the years 1839 and 1849 she has supplied, or has issued orders to supply, to sea-coast fortifications at least two thousand new pieces of the largest calibre. The increase of heavy ordnance in the batteries of Gibraltar within that period was eighty-two pieces, and at Portsmouth and vicinity it was two hundred and eighty-seven pieces.

Sir Thomas Hastings, of the Royal Navy, under examination before a committee of the House of Commons, said: “I was asked just now whether the guns at Portsmouth or other places had been fired in anger. I should be glad to bring under the consideration of the committee that the introduction of steam makes it much more possible now to make attacks upon any certain points. From the different points all along the channel a concentration may be made of a very large body of steamers, and under such circumstances an equipment" (he is speaking of sea-coast batteries) " which would have answered very well when you had only incidental attacks to contemplate from sailing vessels might be insufficient when you could bring twenty-five or thirty vessels carrying the

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