Imatges de pÓgina
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upon our lake shipping, our lake commerce, and our lake towns, if no precautions were taken to guard against it.

The commerce of the lakes will soon be worth to us as much or more than the commerce of the Atlantic.

During the season of lake navigation there is put afloat upon those waters every week, on the average, millions of American property, besides vessels and the lives of American citizens.

In no part of the world, except in the offings and harbors of the great commercial emporiums, is there to be found such a concentration of merchandise afloat. Nor is there, in case of our naval inferiority upon the lakes, any part of the world that affords such an abundant harvest of prizes to tempt the cupidity of seamen.

It is the policy of this country never to be the aggressor; it loves peace and hates war, and therefore it is not likely ever to be the party to strike the first blow in war. That is an advantage at which Great Britain generally aims, and that she fully understands and appreciates the importance of striking quickly upon the lakes in case of war with this country we have evidence conclusive.

Before she sent her minister plenipotentiary here with his ultimatum, when the friendly relations between the two countries a few years ago seemed to be so much in danger, she first assembled a fleet of fifty-odd sail in our waters, and upon our frontiers one-third of the whole British army, notwithstanding that she was at that time engaged in two distant and expensive foreign wars.

No one who, calling to mind those times, will examine her military journals of that day can fail to be impressed with the fact that her forces were especially arranged with a view to Canada and the lakes, and that there the first blow, or a blow synchronous with the first, was to be struck. Her intentions then were too manifest to be forgotten or disregarded even now.

It is true the war might commence during the season when the navigation of the lakes is annually closed, and when, consequently, all naval forces would be tied up. In that case we should have nothing to fear. But it might commence in the height of the commercial season ; and the war might be commenced on her part by first admitting from the sea a fleet of small-class vessels, passing them up through the Canadian ship-canals into the lakes, and there letting the declaration of her intentions consist in an attack upon Buffalo, Chicago, and other lake towns with their shipping.

These interests are too valuable and important to be left at the mercy of an enemy even for a day. Therefore it would be advisable, so long as Canada is an English colony, to provide against a naval surprise on the lakes.

For this purpose it is only necessary to look to the means of assembling quickly a small naval force on the lakes, and, in the meantime, to place at the several cities and towns, and at the termini of the various railroads and canals along the lake shores, a few pieces of ordnance, according to the plan suggested for the towns generally along the Atlantic seaboard.

The forts which are already on the lakes need not be garrisoned in war only until we acquire the naval supremacy there.

We have canals and railroads by which we could send the frames of vessels and all requisite naval means to the lakes at short notice and in time to re-enforce what we might suddenly assemble there.

It seems, therefore, that, acting upon the policy of so shaping our system of national defence as to secure the naval supremacy in our own waters, we should proceed to build the engines, provide the armaments, and get out at the navy yards of Memphis and New York the frames of a few small men-of-war steamers for the lakes. The engines and the armaments might be placed upon the lake shores at once. The frames, on the first appearance of the war cloud, could be sent there by the Erie and the Michigan canals, put together, and be ready for launching at a moment's warning.

The Mediterranean is an inland sea, so are our lakes and rivers. Eminently continental in its proportions and maritime in its features, our country looks out upon blue water to the east, the south, and the west; the ocean front of the United States alone is greater in extent than the ocean front of the whole of Europe. Therefore, like action to the orator, a navy to us is the first, second, and third chief requisite to any effective system of national defence. Respectfully, &c.,

M. F. MATRY,

Lieutenant United States Nary. Hon. Charles M. CONRAD,

Secretary of War.

No. 7.

Report of Lieutenant J. A. Dahlgren.
ORDNANCE OFFICE, UNITED STATES Navy YARD,

Washington, September, 1851. Sir: I had the honor to receive a communication from the honorable Secretary of the Navy, enclosing certain queries from yourself in relation to the defences of the United States coast, with directions to “ give to the subject my best reflections, and communicate the result to the Secretary of War.” I have complied with the directions of the honorable Secretary of the Navy, as far as permitted by the limited time allowed for the purpose, and now beg leave, very respectfully, to lay before you such facts and opinions as have a bearing on the subject-matter of the queries proposed.

Query 1.- To what extent, if any, ought the present system of fortifications for the protection of our seaboard to be modified, in consequence of the application of steam to vessels-of-war, the invention or improvement of projectiles, or other changes that have taken place since it was adopted in the

year 1816? Shells projected horizontally from cannon are most destructive agents when used against shipping, but are not so efficacious against the masonry of regular works as shot, though in entering an embrasure and bursting they might do considerable mischief.

So far, therefore, as casemated batteries are concerned, shells have added very little to the power of ships; but against guns en barbette they will be found of material assistance, especially if charged with balls and used as shrapnel. And against open works, the concentration afforded by the wellserved broadsides of one or more ships, should suffice to silence the works, if the vessels have no unusual disadvantages to encounter, and are brought within sure distance.

On the other hand, shells are exceedingly destructive to vessels if exploded in their sides; but as land works already possess, in shot, especially when heated, superabundant means for destroying ships that will expose themselves long enough to their fire, it may, on the whole, be deemed fairly doubtful whether, in a general view, the introduction of shells has materially altered the relations of fort and ship when opposed to each other.

If the question between them were merely the relative capacity, so far as attack and defence were concerned, there would be no difficulty in solving it. But in the great majority of cases, where the sea defences of the United States are concerned, the true question is in regard to the capacity of ships to endure the fire of forts long enough to pass them without so much injury as to interfere with the subsequent operations.

And it is on this account that the application of steam is to be considered as materially affecting the power of forts. For whether it be used as a chief motive power or as an auxiliary, it gives great facility in concentrating and appearing suddenly on given points, and in assuring a certain and rapid transit when required to pass the fire of a fort.

In the defence of nearly every one of the large commercial cities, it will be observed that the chief reliance to prevent the approach of an enemy is by fortifying some approach to it; tbe naval question merely touches the practicability of passing the fire of these works, and not of sustaining it any longer than may be necessary in the most rapid movement that the ship is capable of.

To illustrate this practically let us turn to the mode proposed in the engineer's report* for excluding an enemy from the lower bay of New York by a fort on Sandy Hook, with floating batteries and bomb ketches inside.

The ordnance commonly mounted in the coast fortifications are 32-pounders, 42-pounders, and eight-inch howitzers. The effective fire of the 32-pounder can hardly be said to extend beyond a mile where heavy ships are concerned.

At that distance the penetration will not exceed fourteen inches when the shot strikes the surface fairly and directly. If the impact be oblique or on ricochet, the penetration is decreased accordingly. The effect of the fire is further decreased by the unavoidable deviation of shot at the distance of a mile, and by the movement of the object which is changing its position in direction and distance. It would be difficult to estimate correctly the number of shot which would have a maximum penetration under these circumstances, but perhaps not more than one in ten. The forty-two pounder and army eight-inch howitzer will not vary this capacity considerably, and it seems reasonable to assume that, if the distance be greater than a mile no material injury will be experienced from such pieces by a heavy ship when under way.

The sketch annexed represents the localities in question as given by the chart of the Coast Survey. T'he track at mean low water allowed to the heaviest steamerst is shown by the coloring.

The effective fire for the proposed fort as indicated by the circle, evidently covers no considerable part of the passage, and if a steamer chose to take the main channel she would, by keeping its extreme right, be under fire about six or seven minutes, and never approach the guns of the fort nearer than fourteen hundred yards, thus rendering the chances of any damage exceedingly slight. But the swash channel offers sufficient depth for her draught, and by using it the steamer would pass entirely out of reach of the fort. The sole reliance, then, to exclude the fleet becomes the floating batteries and boinb ketches; whether they may be trusted or not will be cons dered subsequently; the present object is merely to inquire if the fort has the power of itself to exclude shipping.

It seems evident, therefore, that while it is very doubtful whether forts have gained any advantage from the use of shells, it is certain their efficacy has been considerably diminished by the application of steam to the vessels-of-war, which by their decreased draught are enabled to enter channels not accessible to ships-of-the-line, and when obliged to pass the fire of permanent works are enabled to do so in so little time as hardly to afford the batteries an opportunity to effect any essential damage.

Query 2.–What reliance could be placed on vessels of war or of commerce, floating batteries, gunboats, and other temporary substitutes for permanent fortifications ?

In proceeding to answer this query, I find the ground already occupied by certain propositions contained in an official document drawn up in 1840 in relation to the defences of the coast. The source from which these views emanate and their official character entitle them to full consideration, so that I do not

• To War Department, 1840.
† Susquehanna, full loaded, draws nineteen feet eleven inches.

Skech of Iluok with fort Its fire and channel way.

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The eff ctive fire of the fort is shown by the circle. feel at liberty to disregard them in treating the question proposed, and it becomes imperative to scrutinize them; because, if correct, they not only establish what they were designed to prove, the unfitness of naval forces for protecting the coast, but also their utter unfitness for any purpose whatever, which it is presumed was not contemplated. The passages referred to are as follows :

Even should all these, in the form we have presented them, be objected to, we may still challenge opposition to the following broad propositions, namely:

First. 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.

Second. As, from the nature of the case, there can be no reason for expecting an attack on one of these points rather than 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,

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

To the first proposition there lies a reasonable demurrer, because, under the circumstances likely to attend the defence of any harbor or roadstead which is approached by a channel, great disadvantage must accompany the attempt, particularly when the passage lies among the shoals, of which there is no indication, save by artificial marks or the lead. Where the movements of ships are only limited by bold shores there can be little embarrassment in keeping them from danger; but where the keenest eye can detect nothing on the surface of the water to give warning of the risk, and a slight error in the course or a tideeddy may ground a ship directly under fire, it is evident that the attention requisite to clear these obstacles successfully will prevent the officers of a fleet from giving full directions to its offensive powers, though at the very time the opposing ship may be concentrating a deliberate and destructive fire on the leading ship attempting to enter, or the assailants may be compelled by wind and weather to postpone essaying the entrance, even under these disadvantages; while thus detained he must be exposed to the severe gales and to much damage, a consideration not to be overlooked on our coast, even in the summer months. In 1778 the English and French fleets, then off Rhode Island, were separated from each other while mancuvring for the weather gauge during the month of August, and many of the heaviest slips dismasted on both sides.

On the other hand, the defending force, fully cognizant of the difficulties which await the enemy, either take such position at anchor, or under way with steam or sail, as will be best suited to annoy the enemy when most occupied in clearing the intricacies of unknown shoals, and increase the danger by concentrating a deliberate fire at a moment critical not only to the vessel most exposed to it but to those which follow and are liable to be thrown into disorder by the least mishap.

Be it remembered that this capacity of transferring the power of its armament from one point to another is the essential quality in the present case which the fort does not possess.

Under such circumstances the most cool and brave are apt to hasten too much, naturally desiring to shorten the time of inaction, and to make some return to the fire of the enemy; hence the liability to lose the services of one or more ships in the moment of greatest need.

Well known instances of this may be cited. While standing in to attack the French at the Nile, Nelson lost the use of the Culloden, 74, which grounded on a shoal, though not even under fire at the time, and remained there useless during the whole action. At Copenhagen three of his line grounded on a shoalthe Agamemnon, 74, the Russell, 74, and Bellona, 74; and, in leaving their anchors during the suspension of hostilities, the Defiance and Nelson's own ship, the Elephant, with several others, grounded under the guns of the ThreeCrown battery.

The defending force has, moreover, the advantage, if anchored, of being able to post some guns ashore so as to enfilade vessels taking the direction of its own line, and also prevent the weather ships from being doubled on by the enemy.

Every naval man will comprehend the difficulties of navigating a flect of heavy ships along channels skirted closely by shoals and commanded throughout their extent by the guns of an enemy's line; and the advantages, on the other side, of being able deliberately to rake ships approaching in that way will be very apparent.

Among the events of the revolution may be found an apt illustration of this: In 1778 a large force was despatched from France with the view of surprising the English fleet in the Delaware. Philadelphia had been evacuated, however. The Count de Estaing followed to New York, and appeared off that barbor about the 10th of July. Lord Howe was by no means prepared for his arrival, but, nevertheless, he proceeded with energy and judgment to defend the entrance with a force vastly inferior to that of the enemy.

H. Rep. Com. 86—31

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