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or channels, or shoals, that before were adequately guarded by their shallowness. The bars at the mouth of the Mississippi formerly excluded all but small vessels-of-war, and the strong current of the river made the ascent of sailing vessels exceedingly uncertain and tedious. Now these bars and currents are impediments no longer; and all the armed steamers of Great Britain and France might be formed in array in face of the city of New Orleans before a rumor of their approach had been heard.

Had the English expedition of 1814, attended by a squadron of large armed steamers, arrived at the mouth of the Mississippi, a few transports might have been taken in tow, and in a few hours the whole army would have been before the city; or twelve or fifteen such steamers could have carried the whole

army up in half a day, without the delay of transports. Will it be contended that the attack in that form would have been repulsed with the means then in General Jackson's hands? Would the landing, or even the presence on board these steamships, of the British troops have been necessary to burn the city or put it under contribution? Is there anything now but the existence of forts on the river to prevent the success of such an attack by fifteen or twenty steamers-ofwar, allured thither by the vastly increased magnitude of the spoil?

But there would have been, even then and with those means, one reason with the enemy for avoiding the channel of the river, namely, the existence, seventy miles below New Orleans, of old Fort St. Philip. I will not venture to say that in the then condition of that fort it could have repelled such an expedition, though it did very manfully resist a protracted bombardment; but I do not doubt that the existence of even that feeble work would have had weight in settling the mode and channel of approach, and in turning off the attack into circuitous and tedious avenues, and thereby gaining some time for preparation. I am confident, however, that on the completion of the repairs to that work, now well advanced, and on the completion of the exterior battery of Fort Jackson, (a new fort opposite,) no attack of that nature, even of twice the force, could penetrate by that avenue to the city of New Orleans.

The use of war steamers against New Orleans may take another phase. If deterred by the forts above mentioned from an attack by the river, an enemy might again take the anchorage off Ship island, and transport his army, either on board steamers of light draught or in boats towed by such steamers, to the foot of Lake Borgne, whence his march to the city (a distance of twenty-eight miles through an unpeopled district) would be over one of the best roads in Louisiana.

There is nothing in the shallowness of Lake Borgne to prevent this, nor are there now any defences on the way, though it is to be hoped that the erection of a tower and battery at Proctor's Landing, which has been strongly urged for some years, and which would effectually close this aperture, will at once be ordered by Congress.

If, as during the war of 1812, it were now necessary to pass the troops from the ships to the shore by means of tow-boats, we might, perhaps, considering the augmented population of the city and environs, trust for sufficient notice and preparation to the time that must elapse before a considerable number could be landed; but with ten or fifteen light-draught war steamers, fifteen thousand men could be landed and on their march towards the city within twenty-four hours of dropping anchor.

All other avenues to New Orleans from that quarter have, since the war of 1812, been well closed by permanent forts and batteries.

We have another illustration on the Gulf of this action of hostile steamers through shallow channels, and that may be worth adducing. Fort Morgan, at Mobile Point, defends very well the main channel into Mobile bay, and there is no other entrance for sailing vessels-of-war. But the smaller class of war steamers would find water enough near the end of Dauphin island, and, keeping

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out of reach of the guns of Fort Morgan, could pass up into the bay. They could without difficulty ascend as high as the city of Mobile, and reach that place moreover in three hours. A dozen such vessels could in that short time carry up, if they were needed, five thousand soldiers. It is surely not too much to say, therefore, that Mobile, one of our greatest depots of cotton, is by this new inlet for an enemy's cruisers much exposed. But this is not all the danger. The large fleet of ships, often one hundred in number, and of the largest class of merchantmen, that lie for months awaiting their cargoes in the lower part of the bay, are within an hour's run of such steamers from the open Gult, and might be destroyed either by the same expedition that ascends to Mobile, or by one sent for that particular purpose.

For this and other serious consequences of leaving open this entrance to Vobile bay, the sure and the cheap remedy is the placing of a small fort at the cast end of Dauphin island, a work already wisely ordered by Congress. When it is said in general that the light draught of these vessels opens avenues of attack before detended by nature, it must not be supposed that therefore it is part of the system of defence to fortify all shallow channels. Whether shal low passages will require defences or not, will depend entirely on the importance of the objects to which they give access and the power of the attack that may be directed through them, and not all on the circumstance that an enemy's steamers may enter them without difficulty.

There are a great many entrances and liarbors on the coast, not shoal harbors merely, but many affording water enough for the largest vessels, that will require, if any, no other defences than such as can be prepared in time of war, because there are no objects upon these waters of a nature to provoke the cupidity of hostile cruisers: having nothing to lose in this way, they will have nothing to fear. The shallow and difficult avenues to great and valuable objects are those for which we have to provide defences in dition to defences that were necessary before the introduction of war steamers. The danger of the Hell Gate passage to New York sufficed to keep any man-of-war from attempting to sail through, but it proves to be no impediment to steamers. The “ Broad Sound" channel and also the “Gut” channel into Boston harbor are easy tracks for large steamers, though next to impracticable to line-of-battle ships and frigates; and so with other channels and other places.

In considering to what extent the introduction of steamers into war service may help the coast defence of the country, should we assume that we ought to rely upon them to repel the enemy's steamers, so dangerous in coming without warning and penetrating promptly through all natural obstacles up to the vital points of the coast, we should commit a very great error, though it is perhaps a natural one on a cursory examination, as it certainly is a frequent one. It would be a fatal error if practiced upon by a nation having more than one or two important ports, and even with such nation it would be the most expensive of all resorts.

This cannot be a safe reliance with war steamers any more than with sailing vessels-of-war, and a few words may make this clear.

I do not assert that armed vessels would not be useful in coast defence. Such an idea would be absurd. I shall even have occasion to show a necessity for this kind of force in certain exceptional cases. It is the general proposition, viz: that armed vessels and not fortifications are the proper defences for our vulnerable points-a proposition the more dangerous because seemingly in such accordance with the well-tried prowess and heroic achievements of the nary that we have now to controvert.

Boston, New York, Philadelphia, Baltimore, Charleston, and New Orleans are, we will suppose, to be guarded, not by forts, but by those vessels, on the occurrence of a war with a nation possessing large naval means. We know that it is no effort for such nations to despatch a fleet of twenty line-of-battle ships and frigates, or an equal number of war steamers, or even the combined mass, both fleets in one.

The United Service Journal shows that in the month of August last Great Britain had actually in commission in their navy, in a time of profound peace, thirty-eight line-of-battle ships and frigates, thirteen sloops-of-war, and upwards of fifty smaller armed sailing vessels, together with forty-eight armed war steamers and near forty unarmed steamers.

What, then, shall we do at the above-named ports severally? Each is justly felt to be an object worthy of an enemy's efforts, and each would be culpable in sending elsewhere any part of the force required for its own defence. Each, therefore, maintains a naval force equal at least to that the enemy is judged to be able to send promptly against it. Omitting any provision for other places scarcely less important, what is the result? It is, that we maintain within the harbors of, or at the entrance to, these places, chained down to this passive defence, a force at least six times as large as that of the enemy.

He does not hesitate to leave his port, because it will be protected in his absence by its fortifications, which also will afford him a sure refuge on his return. He sails about the ocean depredating upon our commerce with his privateers and small cruisers, putting our small places to ransom, and in other ways following up appropriate duties, all which is accomplished without risk, because our fleet, although of enormous magnitude, must cling to ports which have no other defence than that afforded by their presence. They cannot combine against him nor attack him singly, for they cannot know where he is, and must not, moreover, abandon the objects which they were provided expressly to guard.

It would really seem that there could not be a more impolitic, inefficient, and dangerous system, as there certainly could not be a more expensive one.

A navy, whether of war steamers or sailing vessels, should be aggressive in its action. It should, by carrying the war into the seas and upon the coast of the enemy, direct its calamities from our coast and commerce; but the system we are now considering involves the absurdity of relinquishing all the incalculable advantages of mastery upon the ocean to an enemy who nevertheless may possess but a sixth of our naval power.

To bring other means even in partial substitution for this defence by ships and steamers, or to give it local auxiliary aid, by way of reducing its inordinate magnitude, would be to confess its inappropriateness for harbor defence. We know that other comparatively cheap means may be substituted, but this is just what the proposition denied. Naval means would be useful undoubtedly. The question is, whether they would be sufficient; and we see some of the consequences of making them sufficient. We come thus to examine the defensive arrangements that can be made in aid of or substituted for armed sea-going vessels.

These arrangements may be of two classes, namely: first, fixed forts and batteries on the land, and in some cases movable batteries of heavy guns: and second, upon the water-floating batteries of all kinds, gunboats, &c., fixed or movable.

There are doubtless situations where it may be necessary for us to present a defensive array, at the same time that to do so by fortifications alone would be impracticable; and it is not therefore prejudging the question we are about to examine. It is neither underrating fortifications nor overrating floating defences to say that these last are some or all of them indispensable in such positions.

Any very broad water, where deep soundings may be carried at a distance from the shores, greater than effective gun range, and where no insular spot, natural or artificial, can be found or formed nearer the track of ships, will present such a situation ; and we may take some of our great bays as examples.

Broad sounds and wide roadsteads affording secure anchorage beyond good

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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 1918 that there should be a suitable and timely provision of appropriate floating defences. And until the invention of man shall have caused an entire rerolution 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 barbors 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

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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 themselves 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

for gim, 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

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

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