« AnteriorContinua »
larger scale. It might often happen, moreover, that our own vessels-of-war would be constrained to take refuge in these harbors, and they should find cover from the pursuer.
Although the harbors of which we now speak afford every variety of form and dimension, there are few, or none, wherein one or two small forts and batteries cannot be so placed as to command all the water that a ship-of-war can lie in, as well as the channel by which she must enter. While the circumstances of no two of them are so nearly alike as not to modify the defences to be applied to them severally, all should fulfil certain common conditions, namely: the passage into the harbors should be strongly commanded; the enemy should find no place after passing wherein he would be safe from shot and shells; and the works should be inaccessible to sudden escalade—that is to say, a small garrison should be able to repel such an assault. With works answering to these conditions, and of degrees of strength in accordance with the value of their respective trusts, this class of harbors may be regarded as secure. I cannot, however, here avoid asking what would be the mode of defence, if purely naval, of these harbors ? Suppose the circumstances are deemed to require the pres. ence of a frigate, or a steam frigate, or an equivalent in gunboats; would not two hostile frigates or two steam frigates infallibly arrive in quest? Could there be devised a system more certain to result in the capture of our vessels and the submission of our towns?
2. Another class will consist of great establishments, such as larger cities, naval depots, &c., situated in harbors not of too great extent to admit of good defence at the entrance, and also at every successive point, so that an enemy could find no spot within which he could safely prepare for operations ulterior to the mere forcing an entrance.
In this class are to be found objects that are in every sense of the highest value. On the one hand, accumulations of military and naval material, and structure for naval accommodation that could not be replaced during a war, which are of indispensable necessity and of great cost; and on the other hand, the untold wealth of great cities. As these objects must be great in the eyes of the enemy-great for him to gain and for us to lose—corresponding efforts on his part must be looked for and guarded against. If he come at all, it will be in power; and the preparations on our part must be commensurate.
The entrance to the harbor and all the narrow passes within it must be oceupied with heavy batteries ; and if nature does not afford all the positions deemed requisite, some must, if practicable, be formed artificially. Batteries should succeed each other along the channel, so that the enemy may nowhere find shelter from effective range of shot and shells while within the harbor, even should he succeed in passing the first batteries. Provided the shores admit this disposition, and the defence be supplied with an armament numerous, heary, and selected with reference to the effect on shipping, the facts quoted from history show that the defences may be relied on.
If the mere passing under sail with a leading wind and tide one or even two sets of batteries, and then carrying on operations out of the reach of these or any other, were all, the enemy might perhaps accomplish it; but the present supposition is, that with this class his ulterior proceedings, and finally his return, are to be subject to the incessant action of the defences.
3. This brings us to consider a third class, consisting of establishments of importance situated at a distance up some river or bay, there being intermediate space too wide to be commanded from the shores. In such cases the defence must be concentrated upon the narrow passes, and must, of course, be apportioned in armament to the value of the objects covered. When the value is not very great, a stout array of batteries at the best positions would deter an enemy from an attempt to force the passage, since his advantage, in case of sucess, would not be commensurate with any imminent risk. But with the more valaable establishments it might be otherwise. The consequence of success might justify all the risk to be encountered in rapidly passing in face of batteries, however powerful. This condition of things requires peculiar precautions under any system of defence. If, after having occupied the shores in the narrow places in the best manner with batteries, we are of opinion that the temptation may induce the enemy, notwithstanding, to run the gauntlet, the obstruction of the passage must be resorted to. By this is not meant the permanent obstruction of the passage; such a resort, besides the great expense, might entail the ruin of the channel. The obstruction is meant to be the temporary closing by heavy floating masses.
There is no doubt that a double line of rafts, each raft being of large size and anchored with strong chains, would make it impossible to pass without first removing some of the obstructions; and it might clearly be made impossible to effect this removal under the fire of batteries. Such obstructions need not be resorted to until the breaking out of a war, as they could then be speedily formed should the preparation of the enemy be of a threatening nature.
There would be nothing in these obstructions inconsistent with our use of part of the channel, since two or three of the rafts might be kept out of line, ready to move into their places at an hour's notice.
The greatest danger to which these obstructions would be exposed would be from explosive vessels, and from these they might be protected by a boom or a line of smaller rafts in front.
From what has just been said, it will be perceived that when the inducements are such as to bring the enemy forward in great power, and efficient batteries can be established only at a few points, we are not then to rely on them exclusively: In such a case the enemy should be stopped by some physical impediments, and the batteries must be strong enough to prevent his removing these impediments; and also to prevail in a cannonade, should the enemy undertake to silence the works. Not to encumber this report with details in relation to these channel obstructions, I beg leave to refer for them to the same document 206, page 34.
It may be repeated here that such expedients need not be resorted to, except to cover objects of the highest importance and value, such as would induce an enemy to risk a large expedition. For objects of less importance batteries would afford ample protection. It will be remembered that this last power is, when once established in any position, a constant quantity, and although it should be incompetent to effect decisive results when diffused over a large fleet, may be an overmatch for any small force upon which it should be concentrated. At the same time, therefore, that there is the less liability to heavy attack, there will be in the batteries the greater capacity of resistance to others.
It must not be urged, as a reproach to fortifications, that in the case we are considering they are obliged to call in aid from other sources, so long as these aids are cheap, efficient, and of easy resort. By the mode suggested the defence will undoubtedly be complete, every chance of success being on the side of the defence; that is to say, if any confidence is to be placed in the lessons of experince. How, on the other hand, will the same security be attained by naval means? Only, as before shown, by keeping within the harbor a fleet or squadron, or whatever it may be, which shall be at all times superior to the enemy in number of guns.
In a naval defence there will be no advantage in obstructions of any sort, for there can be no lessening of the array of guns in consequence of such obstruction, because if these obstructions are under the fire of the floating defences, the enemy will first subdue that fire and then remove the obstructions at his leisure. If this fire proves too powerful for the enemy, the obstructions will have been unnecessary, and will serve only to shut up our own fleet, preventing the prompt pursuit of a beaten foe.
4. There is a fourth class, consisting of harbors, or rather bays or estuaries, of
such expanse that batteries cannot be made to control the passage. These have been before spoken of. If the occupation of or passage through these must be defended, it must be by other means than batteries upon the shore. The reliance must, from the nature of the case, be a floating defence of magnitude at least equal to the force the enemy may bring. The complete defence of each of these bays would, therefore, involve very great expense-certainly, in most cases, greater than the advantages gained. The Chesapeake bay cannot, for instance, be shut against a fleet by fortifications; and if the entrance of the enemy is to be interdicted, it must be by the presence of a not inferior fleet to his own. Instead of such a system, it will be better to give up the bay to the enemy, confining our defence to the more important harbors and rivers that discharge into the bay.
By this system not only will these harbors be secured, but the defences will react upon the bay itself, and at any rate secure it from predatory incursions, because, as before shown, while Hampton roads and the navy yard at Norfolk are well protected, no enemy would proceed up the bay with any less force than that which could be sent out from the navy yard. In certain cases of broad waters, wherein an enemy's cruisers might desire to rendezvous in order to prosecute a blockade or as a shelter in tempestuous weather, there may be positions from which sea-mortars can reach the whole anchorage, although nothing could be done with guns. A battery of sea-mortars, well secured from escalade, would in such a case afford a good defence, because no fleet will lie at anchor within the range of shells.
In thus distributing the various exposed points of the sea-coast into general classes, according to the most appropriate modes of defence, we do not find that anything can be substituted for fortifications, where fortifications are applicable, and we find them applicable in all the classes but the last, and in the last we shall find them indispensable as auxiliaries. In this last class there are, no doubt, some cases where naval means must constitute the active and operative force; and it is probable that steam batteries may, of all floating defences, be most suitable, as before stated.
Before proceeding to a specification of the positions on our coast requiring fortifications, something more should be said on the general subject, though on another branch, namely: the proper magnitude and strength to be given to these fortifications.
The present system is founded on this principle, to wit: That the fortifications should be strong in proportion to the value of the objects to be secured. The principle will not, I suppose, be controverted, although the mode of apply. ing it may be.
There will hardly be a difference of opinion as to the mode of guarding the less important points. There being no great attraction to an enemy, works simple in their features, requiring small garrisons only, containing a moderate armament, but at the same time inaccessible to the dashing enterprises that ships can so easily land, and which can be persevered in for a few hours with much vigor, will suffice. Circumstances must, however, materially modify the properties of these works, even when the points to be guarded are of equal value. În one, the disadvantage of position must be compensated by greater power; in another, natural strength may need little aid from art; in another, greater width in the guarded channel may demand a larger armament; and in a fourth, peculiar exposure to a land attack may exact more than usual inaccessibility ; but all these varieties lie within limits that will probably be conceded.
As to the larger objects, it has been contended that there has been exaggeration in devising works to cover these, the works having been calculated for more formidable attacks than they will be exposed to.
It is easy to utter vague criticisms of this nature, and it is not easy to rebut them without going into an examination as minute as if the criticisms were ever 80 precise and pertinent.
But let us look a little at the material facts. What is the object of an enemy? What are his means ? What should be the nature of our defences?
The object may be to lay a great city under contribution, cr to destroy one of our naval depots, or to take possession of one of our great harbors, &c.
It was estimated that in the great fire in the city of New York in the year 1835, the property destroyed within a few hours was worth upward of $17,000,000, although the fire was confined to a very small part of the city, and did not touch the shipping. Is it easy, then, to estimate the loss that would accrue from the fires that a victorious enemy could kindle upon the circuit of that great city, when no friendly hand could be raised to extinguish them ? or is it easy to overrate the tribute such a city would pay for exemption from that calamity? Can we value too highly the pecuniary losses that the destruction of one of the great navy yards would invoke and the loss beyond all pecuniary value of stores and accommodations indispensable in a state of war, and that a state of war could hardly replace!
But what are the enemy's means? They consist of his whole sea-going force, which he concentrates for the sake of inflicting the blow.
“ From the nature of maritime operations, such a fleet could bring its whole strength to bear upon any particular position, and by threatening or assailing rarious portions of the coast, either anticipate the tardy movements of troops upon land and effect the object before their concentration, or render it necessary to keep in service a force far superior to that of the enemy, but so divided as to be inferior to it on any one point."*
We have, then, objects of sufficient magnitude, and the means of the enemy consist in the concentration of his whole force upon one of these objects.
With the highest notion of the efficiency of fortifications against shipping, these are not cases where any stint in the defensive means are admissible. Having, therefore, under a full sense of the imminent danger to which the great objects upon the coast are exposed, applied to the approaches by water an array of obstacles worthy of confidence, we must carefully explore all the avenues by land, in order to guard against approaches that might be made on that side in order to evade or to capture the works guarding the channels.
But before deciding on the defences necessary to resist these land attacks, it will be proper to estimate more particularly the means that an enemy may be expected to bring forward, with a view to such land operations.
History furnishes many examples, and the expedition to Flushing, commonly called the Walcheren expedition, may be cited as peculiarly instructive.
From an early day Napoleon had applied himself to the creation of a maritime force in the Scheldt; and in 1809 he had provided extensive dockyards and naval arsenals at Flushing and at Antwerp. On his invasion of Austria that year he had drawn off the masses of his troops that had before kept zealous wateh over these naval preparations, relying now on forts and batteries, and on the fortifications of Flushing and Antwerp for the protection of the naval establishments and of a fleet containing several line-of-battle ships and frigates and a numerous flotilla of smaller vessels.
The great naval establishment at Flushing, near the mouth of the Scheldt, and of Antwerp, some sixty or seventy miles up the river, with the vessels afloat on the river or in progress in the yards, presented an object to England worthy of one of her great efforts.
The troops embarked in this expedition consisted of upwards of thirty-three thousand infantry, three thousand cavalry, more than three thousand artillery, and some hundred of sappers and miners, constituting an army of about forty thousand men.
Mr. Secretary Cass.
The naval portion consisted of thirty-five sail of the line, twenty-three frigates, thirty-three sloops-of-war, twenty-eight gun, mortar, and bomb vessels, thirtysix smaller vessels, and eighty-two gunboats, making a total of one hundred and fifty-five ships and other armed vessels, and eighty-two gunboats. The guns, mortars, &c., provided for such bombardments and sieges as the troops might have to conduct, amounted to one hundred and fifty-eight pieces, with suitable supplies of ammunition and stores of every kind.
The idea of sailing right up to their object, in spite of the forts and batteries, seems not to have found favor, notwithstanding the power of the fleet. The plan of operations, therefore, contemplated the landing a portion of the army on the island of Walcheren, to carry on the siege of Flushing, while another portion proceeded up the Scheldt, as high as Fort Bartz, which was to be taken; after which the army would push on by land about twenty miles further and lay siege to Antwerp, all of which it was thought might be accomplished in eighteen or twenty days from the first landing.
The execution did not accord with the design. Flushing, it is true, was reduced within fifteen days; and in less than a week from the debarkation (which was on the 31st of July) Fort Bartz was in possession of the English, having been abandoned by the garrison. But it was twenty-five days before the main body, with all necessary supplies for a siege, were assembled at this point and ready to take up the line of march against Antwerp. Since the first descent of the British matters had, however, greatly changed.
The French were now in force; they had put their remaining defences in good condition; they had spread inundations over the face of the country; and not only would there be little chance of further success, but the safety of the expedition, formidable as it was, might have been compromised by a further advance; it was therefore decided in council to abandon the movement against Antwerp; the troops accordingly returned to the island of Walcheren, which they did not finally leave till the end of December.
The failure in the ultimate object of the expedition is to be ascribed to the omission to seize, in the first instance, the south shore of the river and capture the batteries there, as was originally designed, and which was prevented by the difficulty of landing enough troops at any one debarkation in the bad weather then prevailing. The capture of these batteries would have enabled the expedition to have reached Fort Bartz during the first week; and, in the then unprepared state of the French, the issue of a dash upon Antwerp can hardly be doubted.
The dreadful mortality that assailed the British army is wholly unconnected with the plan, conduct, or issue of the enterprise as a military movement; unleas, indeed, it
may have frustrated a scheme for occupying the island of Walcheren as a position during the war.
Possession was held of the island for five months; and it was finally abandoned, from no pressure upon it by the French; although, after the first six weeks, the British force consisted, in the aggregate, of less than seventeen thousand men, of which, for the greater part of the time, more than half were sick-effectives being often reduced below five thousand men.
We see, therefore, that an effective force of less than ten thousand men maintained possession of the island in the face of, and in close proximity to, the most formidable military power in Europe, for more than three months. And 19 reason can be perceived why it might not have remained an indefinite period while possessed of naval superiority.
The proximity of England undoubtedly lessened the expense of the expedition; but it influenced the result in no other way material to the argument.
I will allude to no other instances of large expeditions sent by the English to distant countries than t'e two expeditions, each of about ten thousand men, sent, in the year 1814, against this country—one by the way of Canada, the