Part 31

The commanding officer is at the periscope in the conning tower directing the course of the submarine through the periscope, which is a tube arranged with lenses and prisms which gives a view of the horizon and everything above the surface of the water, the same as if the observer in the submarine was himself above water. The steersman is shown just forward of the commanding officer and steers the vessel by compass under the direction of the commanding officer, the same as when navigating above the surface. In the larger type boats the steersman also has a periscope which enables him to see what is going on above the surface. Below decks two of the crew are shown loading a torpedo into the torpedo tube; each torpedo is charged with gun-cotton and will run under its own power over a mile and will explode on striking the enemy. The crew live in the compartment aft of the torpedo room. Aft of this is the engine room, in which are located powerful internal combustion engines for running on the surface and electric motors for running submerged. The electric motors are driven by storage batteries located under the living quarters. Wheels are shown housed in the keel, which may be lowered for navigating on the bottom in shallow water. A diving compartment in the bow permits divers to leave the vessel when on the bottom, to search for and cut or repair cables or to plant mines.]

[Illustration: A SUBMARINE SAILING CLOSE TO THE SURFACE

A submarine running partly submerged with the conning tower hatch open, showing the remarkable steadiness of this type of boat in a semi-submerged condition, a thing no other craft could safely accomplish.]

[Illustration: Another submarine running entirely submerged, periscope only showing. The flag is attached to top of periscope to show her position in maneuvers when periscope goes entirely under water.]

[Illustration: A PHOTOGRAPH TAKEN WITH THE PERISCOPE UNIVERSAL LENS.]

AN ALL-SEEING EYE FOR THE SUBMARINE

Vision under water is limited to but a few yards at best, and hence a submarine boat, when submerged, would be as blind as a ship in a dense fog and would have to grope its way along guided only by chart and compass, were it not for a device known as a periscope, that reaches upward and projects out of the water, enabling the steersman to view his surroundings from the surface. Of course the height of the periscope limits the depth at which the craft may be safely sailed. Nor can the periscope tube be extended indefinitely, because the submarine must be capable of diving under a vessel when occasion demands. But when operating just under the surface, where it can see without being seen, the craft is in far greater danger of collision than vessels on the surface, because it must depend upon its own alertness and agility to keep out of the way of other boats. The latter can hardly be expected to notice the inconspicuous periscope tube projecting from the water in time to turn their great bulks out of the danger course.

The foregoing article describes the type of periscope now in common use on submarines and one of the engravings on this page clearly illustrates the principles of the instrument. A serious defect of this type of instrument is that the field of vision is too limited. The man at the wheel is able to see under normal conditions only that which lies immediately before the boat. It is true that he can turn the periscope about so as to look in other directions, but this, of course, involves considerable inconvenience. On at least two occasions has a submarine boat been run down by a vessel coming up behind it.

[Illustration]

~SEEING IN ALL DIRECTIONS AT ONCE~

As long as the submarine has but a single eye it would seem quite essential to make this eye all-seeing; and since the two lamentable accidents just referred to, an inventor in England has devised a periscope which provides a view in all directions at the same time. This has been attempted before, but it has been found very difficult to obtain an annular lens mirror which would project the image down the periscope tube without distortion. The accompanying illustrations show how this difficulty has now been overcome. While we will not attempt to enter into a mathematical explanation of the precise form of the mirror lens, it will suffice to state that it is an annular prism. The prism is a zonal section of a sphere with a conoidal central opening and a slightly concave base. All the surfaces, however, are generated by arcs of circles owing to the mechanical inconvenience of producing truly hyperboloidal surfaces. The lens mirror is shown in section at _A_ in Fig. 1. The arrows indicate roughly the course of the rays into the lens and their reflection from the surface _B_, which is preferably silvered. The tube is provided with two objectives _C_ and _D_ (Fig. 3) between which a condenser _E_ is interposed at the image plane of the lens _C_. At the bottom of the periscope tube the rays are reflected by means of a prism _F_ into the eyepiece. Two eyepieces are employed. One of lower power, _G_, is a Kelner eyepiece, the purpose of which is to permit inspection of the whole image, while a high-powered eccentrically placed Huyghenian eyepiece, _H_, enables one to inspect portions of the image. The two eyepieces are mounted in a rectilinear chamber, _I_, which may be rotated about the prism at the end of the periscope, thus bringing one or other of the eyepieces into active position. The plan view, Fig. 4, shows in full lines the high-powered eyepiece in operative position, while the dotted lines indicate the parts moved about to bring the low-powered eyepiece into use. A small catch, _J_, shown in Fig. 2, serves to hold the chamber in either of these two positions. The high-powered eyepiece is mounted on a plate, _K_, which may be rotated to bring the eyepiece into position for inspecting any desired portions of the annular image. The parts are so arranged that when the eyepiece is in its uppermost position, as indicated by full lines in Fig. 2, the observer can see that which is directly in front of the submarine, and when the eyepiece is in its low position, as indicated by dotted lines, he sees objects to the rear of the submarine. With the eyepiece at the right or at the left he sees objects at the right or left, respectively, of the submarine. The high-powered eyepiece is slightly inclined, so that the image may be viewed normally and to equal advantage in all parts. Mounted above a plain unsilvered portion of the mirror is a scale of degrees which appears just outside of the annular image. A scale is also engraved on the plate _K_ with a fixed pointer on the chamber, making it possible to locate the position of any object and rotate the plate _K_ so as to bring the eyepiece _H_ on it. The scale also makes it possible to locate the object with respect to the boat.

[Illustration: HOW WE LOOK THROUGH A PERISCOPE

THE PERISCOPE TOP.]

[Illustration: PERISCOPE IN GENERAL USE.]

[Illustration: THE UNIVERSAL OBSERVATION LENS.]

This improved periscope is applicable not only to submarine boats but for other purposes as well, such as photographic land surface work, in which the entire surroundings may be recorded in a single photograph. The accompanying photograph, taken through a periscope of this type, shows the advantages of this arrangement and gives an idea of its value to the submarine observer when using the low-powered eyepiece. Of course, by using the other eyepiece any particular part of the view may be enlarged and examined in detail.

[Illustration: INSIDE OF A MINE-PLANTING SUBMARINE

MINE-PLANTING SUBMERSIBLE.

A Lake type vessel designed for planting contact mines. In naval warfare it is sometimes of advantage to plant mines, either to defend harbors, or in some cases the mines are planted in the course of the approaching enemy. This is a vessel designed for that purpose. The enemy is seen approaching, and the mine-planting submarine runs in ahead of them in a submerged condition and drops a number of contact mines on their course; the enemy strikes the mine and is blown up. A number of vessels were blown up by contact mines of this type in the Russian-Japanese war.]

Accidents and Their Causes.

The accidents which submarine vessels must guard against are as follows: collision, foundering, explosions and asphyxiation. The first danger is, however, no greater than those to which vessels that run entirely on the surface of the water are exposed. The eye of the submarine places the commander on a practical level with the commander of other vessels, so that if a collision occurs it is due to the same lack of watchfulness which causes collisions on the surface of the water.

The submarine boat is less liable to founder than an ordinary vessel, because she is built to withstand a greater pressure of water than other kinds of vessels. Of course, if a submarine springs a leak, she is in grave danger of sinking to the bottom, and there is less chance of the crew being rescued from a submarine, because no one but those on board know of the danger if the boat is under the water.

How Explosions May Occur.

In submarine vessels explosions may occur either through a collection of gases from the batteries or by reason of leaks in the pipes or tanks of the fuel supply system, or through the bursting of the air flasks belonging to the boat, or the air reservoirs in the automobile torpedoes. The greatest danger is from explosive gases and have been the cause of all explosions in modern submarine craft, and the greatest danger in this connection is the liability of a leak in the gasolene pipes or tanks. This gas is a heavy gas and so goes to the bottom of the vessel, where it is not so easily detected as a gas which rises. There is no certain way of guarding against leaks of gasolene. A leak may occur at any time in a pipe or tank of gasolene through some cause or other no matter how carefully inspected, and the gas from this is so active that it will go through the tiniest hole imaginable--even through a hole which water will not penetrate. The crew of a submarine is always subject to this danger unless the tanks are built outside the hull of the ship.

How the Air May Become Poisoned.

There is a constant danger of asphyxiation to the men in the submarine. A very small leakage of gas or the exhaust from an internal combustion engine may make the air so impure that those aboard will be overcome. A great deal of care must be taken to keep the air pure and to warn the crew at the first sign of danger from this.

When submarines first came into practical use, it was found a good idea to take a number of little white mice down with the vessel to warn all if the air began to become impure. As soon as this occurred, the mice became distressed and squealed as loudly as they could, thus warning those aboard the ship of danger. The mice felt the impurity of the air quicker than the men, not because they had any special gift to discover when the air was bad, but because they breathe much more quickly than man--take shorter and many more breaths.

Now, however, a chemical device has been invented which is affected in such a way as to ring a loud bell, if the air in the vessel becomes impure to such an extent that there is any danger.

Breathing the same air over and over may fill the vessel with carbonic acid gas. There should be no great danger from this, however, as submarines are now built sufficiently large to provide enough actually pure air for each man aboard for forty-eight hours, and it is hardly conceivable that a submarine need be submerged more than half that length of time under any conditions.

Of course, then, too, there is the danger of accident due to carelessness or ignorance. In other words, it is just as difficult to make a fool-proof submarine as a fool-proof anything else. Wherever anything is constantly dependent upon the continuous careful attention of human beings, there is constant danger of accident, whether it be on board a submarine, a railroad train, steamship or in connection with anything else.

[Illustration: A SUBMARINE UNDER THE ICE

UNDER-ICE SUBMARINE TORPEDO BOAT.

Submarine designed to navigate submerged under the ice, in ice-bound countries. Vessels of this type could enter harbors and destroy the enemy’s shipping at will. A vessel of this type would also be of value in transporting mails, passengers and cargoes between ice-bound ports where navigation by surface vessels is closed for several months in the year.]

Story of How the Submarine Has Been Developed.

It is only within the past twenty years that man has been able to successfully navigate under the surface of the water.

~WHO MADE THE FIRST SUBMARINE BOAT?~

It has been a dream of inventors and engineers for the past three hundred years.

During the reign of King James I. a crude submarine vessel was built of wood, and was designed to be propelled by oars extending out through holes in the side of the vessel, the water being prevented from coming in through the openings by goat skins tied about the oars and nailed to the sides of the boat, which made a water-tight joint, but at the same time gave flexibility to the oars, so that by feathering them on the return stroke they could be manipulated to give head motion. Very little, if any, success could have attended this effort.

Nearly a hundred years later a man by the name of Day built a submarine and made a wager that he could descend to 100 yards and remain there 24 hours. He built a boat and submerged it in a place where there was a depth of 100 yards. He succeeded in remaining the 24 hours, and according to latest advices is still there, as he never returned to the surface.

There is very little information as to the construction of these early craft. The first really serious attempt at submarine navigation was made by a Connecticut man, a Dr. David Bushnell, who lived at Saybrook during the Revolutionary War. He built a small submarine vessel which he called the “American Turtle,” and with it he expected to destroy the British fleet, anchored off New York during its occupation by General Washington and the Continental Army.

Thatcher’s Military Journal gives a description of this vessel and describes an attempt to sink the British frigate “Eagle” of 64 guns by attaching a torpedo to the bottom of the ship by means of a screw manipulated from the interior of this submarine vessel.

A sergeant who operated the “Turtle” succeeded in getting under the British vessel, but the screw which was to hold the torpedo in place came in contact with an iron scrap, refused to enter, and the implement of destruction floated down stream, where its clockwork mechanism finally caused it to explode, throwing a column of water high in the air and creating consternation among the shipping in the harbor. Skippers were so badly frightened that they slipped their cables and went down to Sandy Hook. General Washington complimented Dr. Bushnell on having so nearly accomplished the destruction of the frigate.

If the performance of Bushnell’s “Turtle” was such as described, it seems strange that our new government did not immediately take up his ideas and make an appropriation for further experiments in the same line. When the attack was made on the “Eagle,” Dr. Bushnell’s brother, who was to have manned the craft, was sick, and a sergeant who undertook the task was not sufficiently acquainted with the operation to succeed in attaching the torpedo to the bottom of the frigate. Had he succeeded the “Eagle” would undoubtedly have been destroyed and the event would have added the name of another “hero” to history and might then have changed the entire art of naval warfare. Instead of Bushnell being encouraged in his plans, however, they were bitterly opposed by the naval authorities. His treatment was such as finally to compel him to leave the country, but he returned after some years of wandering, and under an assumed name, settled in Georgia, where he spent his remaining days practicing his profession.

Robert Fulton, the man whose genius made steam navigation a success, was the next to turn his attention to submarine boats, and submarine warfare by submerged mines. A large part of his life was devoted to the solution of this problem. He went to France with his project and interested Napoleon Bonaparte, who became his patron and who was the means of securing sufficient funds to build a boat which was called the “Nautilus.” With this vessel Fulton made numerous descents, and it is reported that he covered 500 yards in a submerged run of seven minutes.

~HOW SUBMARINES WERE DEVELOPED~

In the spring of 1801 he took the “Nautilus” to Brest, and experimented with her for some time. He and three companions descended in the harbor to a depth of 25 feet and remained one hour, but he found the hull would not stand the pressure of a greater depth. They were in total darkness during the whole time, but afterward he fitted his craft with a glass window 1¹⁄₂ inches in diameter, through which he could see to count the minutes on his watch. He also discovered during his trials that the mariner’s compass pointed equally as true under water as above it. His experiments led him to believe that he could build a submarine vessel with which he could swim under the surface and destroy any man-of-war afloat. When he came before the French Admiralty, however, he was met with blunt refusal, one bluff old French admiral saying: “Thank God, France still fights her battles on the surface, not beneath it,” a sentiment which apparently has changed since those days, as France now has a large fleet of submarines. After several years of unsuccessful efforts in France to get his plans adopted, Fulton finally went over to England and interested William Pitt, then chancellor, in his schemes. He built a boat there, and succeeded in attaching a torpedo beneath a condemned brig provided for the purpose, blowing her up in the presence of an immense throng. Pitt induced Fulton to sell his boat to the English government and not bring it to the attention of any other nation, thus recognizing the fact that if this type of vessel should be made entirely successful, England would lose her supremacy as the “Mistress of the Seas.”

Fulton consented to do so, but would not pledge himself regarding his own country, stating that if his country should become engaged in war, no pledge could be given that would prevent him from offering his services in any way which would be for its benefit.

The English Government paid him $75,000 for this concession. Fulton then returned to New York and built the “Clermont” and other steamboats, but did not entirely give up his ideas of submarine navigation, and at the time of his death was at work on plans for a much larger boat.

Fulton had a true conception of the result of submarine warfare, and in a letter he says: “Gunpowder has within the last three hundred years totally changed the art of war, and all my reflections have led me to believe that this application of it will, in a few years, put a stop to maritime wars, give that liberty on the seas which has been long and anxiously desired by every good man, and secure to Americans that liberty of commerce, tranquillity, and independence which will enable citizens to apply their mental and corporeal facilities to useful and humane pursuits, to the improvement of our country and the happiness of the whole people.”

After Fulton’s death spasmodic attempts were made by various inventors looking to the solving of the difficult problem, but no very serious efforts were put forth until the period of the Civil War, and then a number of submarine boats were built by the Confederates. These boats were commonly called “Davids,” and it was one of them that sank the United States steamship “Housatonic” in Charleston Harbor on the night of the 17th of February, 1864. This submarine vessel drowned four different crews, a total of thirty men, during her brief career. At the time she sank the “Housatonic” her attack was anticipated, and sharp lookout was kept at all times; but, notwithstanding their vigilance, she succeeded in getting sufficiently close to plant a torpedo on the end of a spar, and sink this fine, new ship of 1400 tons displacement.

It will be seen from the above description that these vessels, while able to go under water, were not controllable.

After the Civil War several other inventors took up the problem of trying to design a submarine vessel that could be controlled as to maintenance of depth and direction under water.

In Europe, Gustave Zede, Goubet and Drzwiezki, and in this country Mr. Baker and Mr. John P. Holland, built experimental vessels.

In 1877 Mr. Holland built a small boat which was called the “Fenian Ram.” It is stated that this vessel was built with capital furnished by the “Clan-na-Gael,” with the idea of using it against the British fleet in an attempt to free Ireland.

While some slight success was met with by these inventors, it was not until about 1897 that any real progress was made.

~THE FIRST SUCCESSFUL SUBMARINE WITH HYDROPLANES~

In 1893, Simon Lake, an American inventor, submitted plans to the United States Naval authorities at Washington for a submarine boat that would navigate between the surface and the bottom by the use of what he called “hydroplanes,” which were designed to cause the vessel to submerge on an even keel. Mr. Lake’s design of vessel was also provided with wheels to enable it to navigate on the water bed. It was also provided with a diving compartment to enable the crew to don diving suits and leave the vessel, in working on wrecks, cutting cables, planting mines, etc.

In 1904 and 1905 he built a small vessel to demonstrate his principles and succeeded in successfully navigating the vessel on the bottom of New York Bay. He then built a larger vessel of about 50 tons displacement for further experimental purposes. This vessel was called the “Argonaut,” and was built in Baltimore in 1906 and 1907. This boat was successful from the start and covered thousands of miles in the Chesapeake Bay and along the Atlantic Coast, New York Bay and Long Island Sound, and was the first successful submarine boat to navigate in the open sea and on the water bed of the ocean.

Mr. Holland had, in 1894, received a contract for a submarine vessel for the United States Navy, and her construction was started in 1895. This vessel was called the “Plunger.” This was the first official recognition given to a submarine boat in the United States.

The Government of France had also given an order for a submarine boat which was under construction at this period.