Page images
PDF
EPUB

THE TECHNICAL

WORLD MAGAZINE

Volume VII JULY., 1907 No. 5

[ocr errors]
[ocr errors]

IFTY million dollars, according to the estimates of the War Department, are needed to complete our system of fortifications for coast defense. It is an urgent demand, because, if we were attacked at the present time by Japan, or Germany, or any other alert and aggressive power, we should be likely to suffer terribly for lack of preparedness in this respect.

So far as forts go, we are excellently provided, but there is an insufficiency of guns, an alarming want of trained artillerymen to shopt them, and a serious deficiency in certain indispensable apparatus for the management of the batteries—not to mention an almost total absence of the submarine equipments, especially for mine-fields, which are required for the protection of our seaports.

In a strategic sense, the weak point of the United States is its enormous length

of coast-line. From the sea we are vulnerable in a great many spots, and on this account the creation of adequate defensive works for guarding our numerous and widely-scattered harbors is necessarily a costly affair. In the building of the fortifications requisite for this purpose no less a sum than $72,750,000 has been expended within the last few years, but, as above stated, the system is as yet incomplete with respect to its equipment, and there is a woeful lack of men behind the guns.

The gigantic scale on which our system of coast defenses has been established is realized very imperfectly by the people at large. On the Atlantic shoreline alone we have no fewer than fortysix modern fortresses. The Gulf has twelve, and the Pacific coast thirteen forts. All of these are provided with high-power guns (though in some instances the number of the latter is insufficient as yet), and are up-to-date in all respects, so far as their construction is

[merged small][ocr errors]

concerned. By the expenditure of the $50,000,000 already mentioned every one of them can be made practically impregnable.

A fortress of this kind, of the highest class, costs about $5,000,000, of which amount rather more than half is spent for guns. It consists of a series of concretelined pits, called emplacements, below the level of the ground, in which the guns stand on their carriages. The pits are placed at considerable distances from each other, in order to offer as poor a target as possible, and as near as practicable to the water's edge. From the water, whether it be river channel or harbor, a grassy slope extends back to the pits. Beneath the grass and several feet of earth is an inclined plane of concrete; but from the viewpoint of an approaching vessel the works are altogether invisible, their outward aspect being merely that of a well-kept bit of landscape.

Such a. fort may have twenty-four guns—twelve large ones, and an equal number of' smaller caliber. The big ones, of twelve-inch and fourteen-inch caliber, intended primarily for attacking battleships, are placed two in each pit. Those of less size, three-inch quick firers, which are mainly for covering and protecting the mine-fields off-shore, occupy two emplacements, six in each. All of which formidable defensive equipment is reinforced by sixteen mortars, in similar pits, some distance in the rear.

Now, to give a notion of the tremendous character of these weapons, it should be explained that a twelve-incb rifle gun is forty feet long, weighs fiftyseven tons, and, with a charge of five hundred and twenty pounds of powder, throws a 1,000-pound projectile a distance of thirteen miles. Be it remembered, incidentally, that a ship is invisible from the water's edge when it is only seven miles away, owing to the curvature of the earth. Such a weapon does effective and accurate work at twelve thousand yards. It fires armor-piercing shells containing heavy charges of a high explosive, so as to burst on impact.

The mortars are even more effective than the big guns. Altogether different from the old-style weapon so called, they are, in fact, short rifled cannon eight feet in length and of twelve-inch caliber, dis

charging cylindro-conical armor-piercing projectiles weighing 1,000 pounds and loaded with a high explosive. One such projectile landing upon the deck of a warship will go far toward putting her out of action. The mortars are set back at a distance from the shore because they do better work at long ranges, being fired into the air at an angle of forty-five degrees—notwithstanding which curve of trajectory the projectiles reach their mark with utmost precision.

It is out of the question for warships, no matter how powerful, to attack with success a fortification of this kind. In order to harm it, they would be obliged literally to batter down the landscape. Meanwhile the defenders are invisible, and the guns (being on disappearing carriages) rise into view only at the moment when they discharge their projectiles. As for the mortars, it may be added that frightful execution was done at Port Arthur by the Japanese with weapons of this type, though they were of smaller size than those here described, throwing shells that weighed only five hundred pounds. They are destined to prove extremely formidable in the warfare of the future.

It is not going too far, then, to describe such fortresses, when they are fully and properly equipped, as impregnable—at all events to attack from the sea. To assail them by land would require a considerable military force, such as could hardly be disembarked anywhere upon our shores. As a matter of fact, however, an enemy would not attempt to capture or destroy fortifications of the kind by naval operations, but would try to run past them. In this effort battleships might easily be successful, escaping'very serious damage, and thus reach an unprotected inner harbor, like that of Xew York, from which point of vantage they could destroy a city or hold it to ransom.

This cannot be done if mine fields obstruct the channel. But, unfortunately, here is the very point in which our arrangements for the defense of our coast cities are weakest. Our military experts have devised the most admirable system of submarine mines in the world, but as yet it is almost wholly on paper. Should war break out with japan, or with Ger

[graphic][merged small][graphic]

many, we should certainly be assailed without warning, and such prompt advantage might be taken of our helplessness in this respect as to decide the issue of the conflict against us before we had a chance to strike an effective blow. Think, for example, of the distressing position we should find ourselves in if half a dozen German battleships gained entrance to the harbor of New York! They might do hundreds of millions of dollars' worth of damage in a few hours, unless we chose surrender as the disgraceful alternative.

According to the estimate of the War Department, only $3,466,322 would be required to provide mines and all incidental equipments for submarine defense for all of'our harbors from Portland, Maine, to Puget Sound. But Congress, which usually does its cheeseparing in the wrong place, has shown a reluctance to put all of this money under water. Thus, for the sake of saving so small a sum, the country has been placed

[graphic]
[graphic]

Range-finding Station.

Vmw Of Plotting Room, Showing Ihi "tracking" Of A Target Ship.

in a perilous situation—the mischief lying in the circumstance that the requisite mines and other material demand a period of many months for their manufacture, while the men to handle them cannot be taught the art in less than a year. Are we to expect, forsooth! that the foe will give us a year to get ready before he swoops down upon us? Even of guns we yet lack one hundred and eighty-seven to complete the armament of our coast defenses.

Floating contact mines of the kind used by both belligerents at Port Arthur arc, as shown by the experience of that campaign, dangerous alike to friend and foe. The sort we employ are submarine torpedoes, anchored usually in lines across a channel and connected by wire cables with the shore, from which they may be exploded by electricity. With such an arrangement, the infernal machines may be rendered entirely harmless when not in use, or at will may be utilized with frightful destructiveness against hostile

The men at work are the observer (looking through instrument), the reader, Warships trvilltT to TUI1 and the recorder (seated). The observer follows the target and the 1'

reader sends the range by telephone to plotting room.

by. The entire mine field obstructing a harbor entrance is by this means controlled by a single operator through the medium of a series of pushbuttons.

One method adopted for such purposes consists in laying off the water surface of the mine fields, by careful survey, in a series of squares arranged like those of a checkerboard. Two telescopes on shore, a couple of miles apart perhaps, can together fix the exact position of a vessel floating anywhere in the channel. These telescopes are electrically connected with two brass pointers which, in an underground chamber within the fort, move upon a map. The map, which represents the mine field, "is likewise checkerboard, each numbered square of which corresponds to a surveyed square of the channel. Obeying the telescopes, the pointers meet exactly where the ship in view happens to be at the moment, and to explode the submarine torpedo nearest to her is simply a matter of push. ing the right button.

Happily, Congress at last shows signs of being persuaded that something really must be done to remedy the deficiencies already mentioned. It has provided $575,000 as a smarter, for the purchase of mines and other apparatus for submarine defense. It has also created a new corps, to be called the Torpedo Artillery, which will attend to the business of operating such military contrivances. This corps is to consist of picked men, who shall have undergone a thorough course of instruction in all matters relating to subaqueous warfare, including the chemistry of explosives, electricity, and the

management of automatic anchors, which last is a science in itself.

For some years past there has been in existence a well-equipped school of submarine warfare at Fort Totten, N. Y., where a limited number of graduates in these arts are turned out annually, both officers and enlisted men, the latter being thereupon assigned to various fortified posts along the seacoast. The method of training adopted is as practical as possible, small steamers being used for planting mines and connecting the cables. The automatic anchors aforesaid are in-genious contrivances whereby the mines may be placed at any desired distance

[graphic]

Explosion Of Submarine Mine.

« PreviousContinue »