Imatges de pÓgina
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fire of the forts therefore so much increased in time as to render the attempt hazardous. Pieces of heavy ordnance can also be mounted on stout merchant ships and steamers, forming a reserve to be placed along the passage where the guns of the forts do not command, so as to sustain a steady cannonade on whatever ships of the enemy may remain in a condition to proceed. Meanwhile a few hours will bring up a fresh squadron, and soon after this will be reinforced, so that fifteen steamers in perfect order will enter the bay. The result must be the capture and destruction of the invading force.

This is the view which I consider fairly presentable of the favorite case so frequently urged, wherein the advantage is enjoyed by the assailing party of selecting time and place without warning to the defending force.

It seems highly probable that the defence of any important point, with some exception as it regards the southeast and Gulf coasts, can be made good with no greater additional force in the aggregate than above mentioned, admitting every advantage that can be claimed for this arrangement of the enemy.

That advantage is limited to a space in time that admits of no accident to force, speed, or any of the multifarious details of a fleet. Its operations must be as precise and perfect as those of the machine that moves each steamer.

From the moment that the hostile fleet comes in sight there is a sure concentration of a superior force, and in a few hours there will no longer be the power to choose. An action is inevitable; and whatever be the result to our own squadron, that of the enemy will certainly be unable to prosecute any enterprise against harbors or coasts for the time.

It is, however, out of the question for any such fleet to hazard itself on a coast where the certain superiority, no matter how small, exists; and the entire line of shore northward would therefore be fully secured against an enemy's vessel.

Southward of Hatteras the necessity of naval means for defence is even more stringent than to the northward.

The objects of attack differ as widely also from those just under consideration as the manner in which shipping must be applied to defence in order to be available.

The resources of private enterprise are no longer aggregated so densely, but are scattered along the country bordering on the coast in a manner that renders it difficult for the most eager marauder to do much in his line.

The commercial cities are pretty well defended from the extensive movements of large fleets by the bars which border the channel-ways to their harbors.

The interior lines of communication formed by the long downs of sand that skirt the Atlantic shore are, however, accessible to vessels of inferior force, and the command of these would give the control of all the trade that by its light draught finds convenience in the smoother waters of the inlet. The most important debouch, however, for the resources of the country is the outlet of the Mississippi, through which is poured, in a never-failing tide, the rich products of the great valley of the river. To check this, to impede it, to harass in the least degree, would be an evil of the greatest magnitude, and be felt in the remotest regions of the west.

The general character of the southern shore of itself prevents the operations of vessels of heavy draught; hence the defence must be nearly the reverse of that recommended for the shores north of Hatteras. There heary ships will lie inshore, and light cruisers be thrown out seaward to watch the motions of the main force of the enemy, and coastwise to check small marauders or parties for wood and water. On the southeast and Gulf coast the light steamers and vessels of the third class would keep the inlets and their approaches and the various avenues contiguous to the Mississippi. While seaward the heaviest ships must abide the first brunt of the attack and defence at all risk, so as to cripple the forces of the assailant should he be strong enough to close with the inshore squadron.

The true and only key, however, to the defence of these shores, and to the immense interest there collected, is the Havana. The island to which it belongs enters its western extreme into the Gulf, leaving but two passages for vessels so narrow as to be commanded with the greatest facility; these are the great thoroughfares of trade and the mail steamers from New Orleans to California and New York. Hence if the use of the Havana be even at the disposal of an enemy while in the hands of a neutral power, each and all of these interests could be with difficulty defended, even by a superior naval force, and never guaranteed against severe losses. While from it as a United States port, a squadron of moderate size would cover the southeast and Gulf coasts, protect the foreign and inshore traders, and secure the lines from New Orleans or New York to the Pacific States by way of the Isthmus, its occupation would necessarily

be the object of every expedition, military or naval, preliminary to any attempt on the southern trade or territory.

At present the force of large vessels for the southeast coast would be obliged to use the harbor of Brunswick as their depot, refuge, and centre of operations. The report of the commissioners has already decided this to be the best south of the Chesapeake. With the command afloat, Key West and the Tortugas might be used, but not otherwise, as no supplies are to be had at either, and no water at the latter. Pensacola would have to answer for the Gulf shore.

The coast of the Pacific States differs in many respects from that of the Atlantic in formation as well as in condition.

The circumstances of settlement, product, and trade have yet to determine much that will govern in the extent and application of the elements of defence.

At present there can be no doubt that the two great harbors at San Francisco and the Columbia river will require immediate measures for their protection. The sites of land works have probably been vindicated by the engineers sent for that purpose, though some time must elapse before these can be completed.

It seems, therefore, that the naval force in these regions should be of the most effective character in power and number, singly and collectively, inasmuch as it must for a while be the exclusive reliance for a defence of any kind of harbors, as well as of coasts. The squadron should always be able to land at any point a force of two thousand seamen and five hundred marines, which, with twenty or thirty of the boat howitzers on their field carriages, would be found an effective auxiliary in emergencies.

The manner in which our own squadron operated along the coast of California while held by the Mexicans will best exhibit the character of the attempts likely to be made by an enemy against our own people now inhabiting that State. If the views above expressed, in relation to the defence of the United States harbors and coasts, be correct, it then remains to consider the species of naval force which will be required to perform the part assigned to it.

By referring to the navy list it will be seen that the number of heavy ships that is available, or could be made so by necessary repairs, consists of nine lineof-battle ships, twelve frigates, and five steamers.

This force is obviously too small for the objects for which a navy should be designed. If the number already assumed to be required for the defence of the Atlantic coast in war be applied to that purpose, it would leave a very insufficient force for the Pacific shores, for the protection of the line of communication by sea between the Atlantic and Pacific States, and for general cruising to cover our own commerce, and annoy that of the enemy.

Not only is the effective number of the present navy too small, but the character of the force has been depreciated to a very serious extent by the superior powers of offence that have been conferred on the large steamers that now constitute part of a navy here and elsewhere. The cannon carried usually as the main reliance of line-of-battle ships and frigates are thirty-two and forty-twopounders. In our service the latter calibre may be considered as exceptionable, inasmuch as it is not recognized by the regulations of 1845.

The war steamers carry sixty-four pounders. It is true that the line-of-battle ships may have one hundred of the thirty-two-pounders, while a steamer of the same tonnage has but three of the sixty-four-pounders.

But it will be admitted that if the constituent of one battery is deficient in any one element of power, which is possessed by that of another battery, that no mere increase in the number will compensate for this defect. Thus, if the thirty-two-pounder shot fired with nine pounds of powder be inferior to a shot of sixty-four pounds fired with sixteen pounds of powder in the distance to which it will range with sufficient force to do material damage, then it is plain that so long as that distance can be preserved it will matter little whether a

H. Rep. Com. 86–32

ship oppose one hundred or one thousand thirty-two-pounders to the three sixtyfour-pounders: she will receive constant damage from the repeated efforts of the small number of large pieces without the power of inflicting any harm by her large number of small pieces. A similar relation, in effect, may be noted in the effects of other military projectiles. Thus, we know that grape from a thirty two-pounder would be harmless against the side of a ship, when the shot would pass through easily, and yet the stand of grape is composed of three-pound shot which, even if fired separately, would still be very little nearer the effect of the thirty-two-pounder shot.

The important question is in relation to the capacity of the steamer to maintain the distance suited to her powers of annoyance—and of this there can be little doubt since the passage between the United States and England is made with ease and certainty in the severest winter weather by the steam packets, their average speed being then seven to eight knots with fair and foul winds, and they could in all probability go very little below their highest rate in any weather in which cannon could be used.

Those who have witnessed the performanse of the Mississippi in some of the Mexican “northers” know what can be done by a good steamer in a strong gale. Thus the twenty steam frigates would be very unequally matched in action, by our covering squadron of sailing ships with the thirty-two and forty-two-pounders, if it could be said that they were matched at all. The remedy for this is not difficult, and can readily be attained by a reorganization of our armament, though it would be more expensive to adapt the present sailing ships fully to the ordnance which experimental practice has indicated as preferable than to build new ships. Thus a two-decker would carry the same weight of metal, but not the same number of cannon. Hence, it would become necessary to reduce the number of ports, and to re-distribute them along the broadside; and to do this, the whole planking and frame, nearly to the water's edge, must be removed and replaced to suit the changes required in piercing the side with the proper number of ports—involving an expense equal to half the cost of a new ship.

They would still need an addition that could not be dispensed with, which is an auxiliary steam power sufficient to give a moderate rate in a calm, in manæuvring or in getting out and in harbor. For this purpose, greater length would be required than any of our present frigates possess, as they now barely stow the provisions and water required for distant cruising. If these ships be cut and lengthened, the cost in connexion with that necessary for heavier ordnance will be fully equal to the expense of building new ships with every disadvantage that can attach to a sacrifice of unity of design in model; for no skill in the builder could possibly develop any one essential of form in this piece of patchwork, except by mere accident.

The true policy, not only as regards economy, but in reference also to aecomplishing the object in view, is to commence without delay the reorganization of our naval power by the gradual addition of ships built upon the most recent models, and to carry heavy ordnance as well as an auxiliary steam power.

The experimental practice at the navy yard has developed some points of interest in relation to the pieces likely to combine the several essentials of accuracy, range, and force, and the bearing of all the results has induced me to propose the construction of a class of ships designed to unite a higher degree of efficiency than any frigate or seventy-four mounting the present armament, &c.

Instead of twenty-six thirty-two-pounders, and four eight-inch shell guns on the gun deck, the new frigate is to carry twenty-six nine-inch shell guns. The comparative penetrating power of the two pieces is shown in the sketch annexed: The thirty-two-pounder shot passed twenty-one inches into an oak target, three-fourths of a mile distant. The nine-inch shell, uncharged, broke through the whole thickness of thirty inches.

Fig. 1.

Hand from a long 32-pounder, charge 9 lbs.- Penetration in oak, distant 1,300 yards, thickness 30 in.

Nine-inch shell, weight 73 pounds, cha ge 94 pounds.

The diminution of force which both would undergo at greater distances would lessen the power of the thirty-two-pounder shot yet more, while the nine-inch shell would still retain every advantage arising from its explosive power. The only pieces of the present force that would approach it being the two eight-inch shell guns, which, in number and intensity of effect, are not comparable to the thirteen nine-inch shell guns.

If the distance were lessened, the broadside of nine-inch shell guns would in weight of metal alone be nearly double that of the thirty-two-pounder and eight-inch shell guns.

On the spar deck are to be no broadside guns, but, in lieu thereof, seven shell guns, of ten or eleven-inch calibre, on pivots, and capable of being pointed around the circle in every direction.

An auxiliary propeller power will be placed astern, for which purpose the length of the ship must be adapted to its convenient reception.

The points of this ship will be:

1st. Cost of Construction. This ought not to exceed the cost of an ordinary sailing frigate, with the additional expense of steam equipment.

The St. Lawrence cost about $350,000; and the cost of a suitable engine, boilers, &c., as furnished by Kemble, would be about $70,000;total, $420,000.

The Susquehanna steam frigate cost very little less than $700,000.

2d. Force. — The broadside weight of metal of the new frigate would be about 1,800 pounds. The Pennsylvanian, three decker, present armament, 2,100 pounds. The Ohio, two decker, 1,500 pounds.

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