Submarine ridge

“ On modern boats the control of depth is most remarkable; it is very common for submarines to make continuous runs of several hours' duration without varying their depth more than a couple of feet. When the headway or motive force of the submarine is stopped, if she has reserved some positive buoyancy she will come to the surface. If she has negative buoyancy she will sink, but while under way with as much as a ton of positive or negative buoyancy the hydroplanes will absolutely control the depth of the vessel. ”

“ As soon as they do so water is forced out of the ballast tanks by compressed air until positive buoyancy is restored and the vessel stops sinking and remains at rest anchored between the surface and the bottom, like an anchored buoyant mine. By winding in on the anchor cables a submarine may then be hauled down nearer the bottom, and by paying out the cables she may rise nearer the surface. ”

“ The record of ships that have been lost, due to striking uncharted rocks and shoals, is a large one, and a more correct topography of the water-beds of our coast and inland waterways should be worked out. In 1899 and 1901 considerable time was spent in experimental work with the submarine boat Argonaut in locating sunken ships and recovering their cargoes. To find a sunken ship it was necessary to search the bottom thoroughly, and many experiments were made and success attained to such an extent that we could search thoroughly an under-water area of from ten to twenty square miles per day. ”

“ On frequent occasions they have been very successful in locating submarines below the surface, since the body of the under-water boat is readily detected from an altitude of a thousand feet or more, even though submerged to a great depth and despite a heavy ripple on the surface that makes the water absolutely opaque when viewed from the deck of a ship. Doubtless they will be employed to an increasing extent as the hunt for the submarine becomes more and more intensive, though their use is very much restricted during the winter months, owing to the frequent and severe storms encountered. ”

“ The distance of 50 yards, which is the usual interval between mines, is five times the breadth of a submarine. By diving to 50 feet, the chance of contact with the mine is removed, and only the lesser danger of fouling the moorings remains. It is perfectly easy to sweep a channel for submarines, as for other vessels, at any time. Where there is any uncertainty about the whereabouts of a minefield, trawlers, or small merchant ships with a very few people on board, can go ahead of the submarines and pilot them out. ”

“ Their displacement—submerged—was 120 tons. It must be remembered that a submarine's surface displacement is always less than when she has filled her tanks to sink her deeper in the water. They were 63 feet 4 inches long and 11 feet 9 inches wide at their greatest beam; steamed from 8 to 10 knots above and 5 to 7 knots below water, carried a crew of seven men, and had a single torpedo-tube. Many experiments were carried out with these little vessels, the net result being that series after series of larger and larger submarines were constructed, each batch an improvement on the preceding one. ”

“ But whether the submarine is used for mining its own or enemy harbors, the outstanding feature of its [121] work is that it does it all under water and therefore the operations cannot be seen by spying eyes.
As we said in Chapter III, the mines are stored in a compartment in the hull of the submarine and this can be shut off from the other compartments by a bulkhead door. It also has a hatch opening through the hull to the water outside, just as the door of a kitchen opens into the back yard. ”

“ You know, there are important fortifications there, because the Navy people expect, in wartime, to use Craven's Bay as a possibly important naval station and shelter for vessels that have to put in. Now, for some time the Army engineer officers have been perfecting a system of submarine mines for the bay. The engineers have a problem on hand as to whether an enemy's submarine boats could sneak into the bay and blow up the submarine mines before the Army woke up to the danger. ”

“ On such a vessel the men cannot go on deck in a storm; in a sea-going submarine a large reserve of buoyancy is therefore essential.
Now in a modern submarine, of five hundred tons submerged displacement, for instance, this reserve should be about one hundred and twenty-five tons, according to the best practice. This means that before the vessel could sink beneath the surface the ballast tanks must be filled with one hundred and twenty-five tons of water. On the surface these tanks are filled with air. The water is permitted to enter by the opening of valves for that purpose. ”

“ This shows the remodelled "Argonaut" with her buoyant ship-shaped superstructure, on a submerged wrecking expedition, as was actually accomplished in the years 1900-1901.
Searching for sunken vessels is, perhaps, the most interesting of all submarine work. It is like fishing. One is always on the qui vive for a "bite." There is hardly a location along our coast or in Long Island Sound that does not have a tradition about lost treasure ships, and every time one gets a "bite"—that is, our lines get fast to some sunken object—excitement runs high in the expectation of some valuable find. ”

“ It is in these, when it is driven from the main funnel point of traffic, that the submarine must do its work. The defeat of the submarine, when at large, turns upon three factors: (1) the under-water offensive—that is, mine-fields, that will tend to keep it within certain areas; (2) the efficiency with343 which ships liable to attack are protected by convoy; and (3) the skill and persistence with which submarines, once on their hunting grounds, are in turn hunted. ”

“ The submarine A, diving to avoid a surface warship, has become entangled in the mooring of a deep-laid mine which is being dragged down on top of her. These mines are often moored at a depth of 60 feet below the surface, which can then be patrolled by surface warships. ”

“ The submarine will have viewing ports for visual observation of its surroundings and of the ocean bottom. A remote grapple will permit collection of marine samples and other objects. The NR-1 is expected to be capable of exploring areas of the Continental Shelf, which appears to contain the most accessible wealth in mineral and food resources in the seas. ”

“ When the submarine, like a fish, gets in the pound it cannot get out, and those in the vessel must either die there or take chances on reaching the surface and swimming to shore.
It takes very little to disable a submarine. The hull is of comparatively thin steel which is easily punctured and the propeller when caught is absolutely useless. Even an ordinary fisherman’s net will disable a submarine, and should one get foul of such a net the chances of getting clear are very slim. ”

“ One important use to which the commercial submarine may be turned is that of navigating under ice fields, between ports which are bound with ice fields during great parts of the year, and also for purposes of exploration and of scientific study.
All navigators know the difficulty of attempting to break their way through the ice fields, since it requires a vessel of tremendous power and great weight to break down or through solid ice. A vessel of this type was first proposed by me in 1899 for exploration purposes in ice-covered seas. ”

“ With the fall of the tide, that here exceeds twenty feet, these disquieting evidences were discovered, and within a few hours Captain Restronguet was the talk of all the cafés of Paris. The French, pioneers in submarine warfare, were now at a loss to explain how a submerged craft could, in broad daylight, enter the breakwater-enclosed harbour and run alongside the caissons of the docks without being discovered, while to deposit three bulky "mines" in water of not more than three fathoms in depth was an exploit that required a lot of explanation as to how it was done. ”

“ While new and larger U-boats are sent abroad on the trade routes, special submarines, less encumbered by the stores and equipment that longer passages would demand, make frequent visits to the fairways to sow a freight of mines. No section of the channels holds sanctuary for the coaster. Close inshore, as in the offing, is all a danger area, open to the stealthy visits of the submarine minelayers. ”

“ In the absence of patrol vessels to drive them down, submarines would naturally run on the surface, and so the rows of upper level mines were made more numerous than those at deeper levels. The stroke of a mine is sudden and powerful, and while a vessel on the surface may survive it, to a submerged submarine it is usually fatal. All classes of vessels shy at a minefield, and that the Germans shared this aversion was shown by captured papers, which made it clear that the submarines dreaded nothing so much as mines. ”

“ Fitted with guards and gently pushing aside the cables which anchor the buoyant mines, the bottom-creeping submarine can proceed slowly and cautiously over the bottom and pass through a mine field with impunity. ”

“ The standard displacement of a submarine is the surface displacement of the vessel complete (exclusive of the water in non-watertight structure) fully manned, engined, and equipped ready for sea, including all armament and ammunition, equipment, outfit, provisions for crew, miscellaneous stores, and implements of every descrirption that are intended to be carried in war, but without fuel, lubricating oil, fresh water or ballast water of any kind on board. ”

“ It is quite obvious that should any accident happen, such as the entry of water, the failure of the machinery, the asphyxiation of the crew (rendering the detaching of a false keel impossible) , &c., the submarine with a reserve buoyancy would at once rise to the surface, while the boat with no floatability would remain where it was and then gradually commence to sink, owing to the fact that it is almost impossible to prevent the water from finding its way, little by little, into the boat. ”

“ The towers upon each side of the river had to be so high that a very deep foundation, going down to the original rock, had to be laid, and the workmen engaged in building it worked in a submarine apartment, supplied with air forced down by a steam engine.
The submarine hydrostat, as it is called, is one of the most ingenious and recent applications of the diving-bell principle. Thirty men may work in it at once, for a number of hours, without any inconvenience ”

“ The enemy, with light, shallow-draft, high-speed picket boats, could probably make it very unsafe for a submarine to travel any considerable distance along the coast in the daytime, or even at night, in surface cruising condition. As it takes considerable time to charge the batteries to enable the boat to run in a submerged condition, should the enemy have control of the surface of the sea, the average submerged radius to-day of a submarine would probably be less than one hundred miles, unless it ran a grave risk of being captured while on the surface. ”

“ The British submarine D-16 was, at this time at any rate, the only under-the-water vessel that could remain under the sea indefinitely. The one real weakness of beneath-the-sea fighters had always been their inability to remain long under water, and for this reason they could operate only within a certain radius of their base. ”

“ Cargo-carrying submarines fitted to under-run ice fields will shorten trade routes by opening up to navigation the Northwest Passage, and will also open up new ports in northern Europe and Asia, and provide an outlet for Siberian-grown wheat and other northern products which are not now utilized because of lack of transportation facilities. ”

“ Equipped with the "mine-evading" guards, they might even work their way into an enemy's harbor and plant mines under a vessel at anchor, or destroy shipping lying tied up at the docks. For defensive purposes a mine-laying submarine would be of great value, as it could readily plant mines, even under the guns of a powerful fleet, to protect its own entrances and harbors.
The submarine Protector, built in 1901 and 1902 at Bridgeport, Connecticut, was fitted with a diving compartment which corresponds to the mine-laying compartment of the 1905 design above referred to. ”

“ At night, and at long ranges, this is not difficult, as the little conning-tower, or tiny periscope tube protruding above the waves, is not easily detected even by strong searchlights, sharp eyes, and marine glasses. But long ranges are of little use to the submarine; and there is always another difficulty—the leviathan battle-ship does not lie still waiting to be stabbed by its sword-fish enemy, but keeps moving about, twisting and turning, at a rate of from fourteen to eighteen knots an hour, while the submarine can only make about eleven knots when submerged. ”

“ It meant probing the trustworthiness of the unyielding steel body, the weight and pliability of her mighty machinery; getting on the track of her imperfections or tricks, and coaxing from her the secrets of her mobility and fantastic fish nature.
A submarine is as full of humours as a woman, and as tricky as a racehorse. She is as sober as a tramp-steamer, and as trustworthy as a tug. She has good qualities and—not good. ”

“ We will assume, for purposes of illustration, that the Sandy Hook entrance to New York Harbor is to be defended. If we strike a fifteen-mile radius from Sandy Hook point, running from the Long Island to the New Jersey shore, and have four submarines take station on that radius line about five miles apart, no ship could pass that radius line without coming within the range of vision of the commander of the submarine, either from his periscope in daylight or at night within the range of hearing of his "submarine ears." ”