The history of warlike inventions is the history of a continual see-saw between the discovery of a new means of defence and the discovery of a fresh means of attack. At one time a shield is devised to repel a javelin; at another a machine to hurl the javelin with increased violence against the shield; then the shield is reinforced by complete coats of mail, and so on. The ball of invention has rolled steadily on into our own times, gathering size as it rolls, and bringing more and more startling revolutions in the art of war. To-day it is a battle between the forces of nature, controllable by man in the shape of “high explosives,” and the resisting power of metals tempered to extreme toughness.

At present it looks as if, on the sea at least, the attack were stronger than the defence. Our warships may be cased in the hardest metal several inches thick until they become floating forts, almost impregnable to the heaviest shells. They may be provided with terrible engines able to give blow for blow, and be manned with the stoutest hearts in the world. And yet, were a sea-fight in progress, a blow, crushing and resistless, might at any time come upon the vessel from a quarter whence, even though suspected, its coming might escape notice—below the waterline. Were it possible to case an ironclad from deck to keel in foot-thick plating, the metal would crumple like a biscuit-box under the terrible impact of the torpedo.

This destructive weapon is an object of awe not so much from what it has done as from what it can do. The instances of a torpedo shivering a vessel in actual warfare are but few. Yet its moral effect must be immense. Even though it may miss its mark, the very fact of its possible presence will, especially at night-time, tend to keep the commanding minds of a fleet very much on the stretch, and to destroy their efficiency. A torpedo knows no half measures. It is either entirely successful or utterly useless. Its construction entails great expense, but inasmuch as it can, if directed aright, send a million of the enemy’s money and a regiment of men to the bottom, the discharge of a torpedo is, after all, but the setting of a sprat to catch a whale.

The aim of inventors has been to endow the dirigible torpedo, fit for use in the open sea, with such qualities that when once launched on its murderous course it can pursue its course in the required direction without external help. The difficulties to be overcome in arriving at a serviceable weapon have been very great owing to the complexity of the problem. A torpedo cannot be fired through water like a cannon shell through air. Water, though yielding, is incompressible, and offers to a moving body a resistance increasing with the speed of that body. Therefore the torpedo must contain its own motive power and its own steering apparatus, and be in effect a miniature submarine vessel complete in itself. To be out of sight and danger it must travel beneath the surface and yet not sink to the bottom; to be effective it must possess great speed, a considerable sphere of action, and be able to counteract any chance currents it may meet on its way.

Among purely automobile torpedoes the Whitehead is easily first. After thirty years it still holds the lead for open sea work. It is a very marvel of ingenious adaptation of means to an end, and as it has fulfilled most successfully the conditions set forth above for an effective projectile it will be interesting to examine in some detail this most valuable weapon.

In 1873 one Captain Lupuis of the Austrian navy experimented with a small fireship which he directed along the surface of the sea by means of ropes and guiding lines. This fireship was to be loaded with explosives which should ignite immediately on coming into collision with the vessel aimed at. The Austrian Government declared his scheme unworkable in its crude form, and the Captain looked about for some one to help him throw what he felt to be a sound idea into a practical shape. He found the man he wanted in Mr. Whitehead, who was at that time manager of an engineering establishment at Fiume. Mr. Whitehead fell in enthusiastically with his proposition, at once discarded the complicated system of guiding ropes, and set to work to solve the problem on his own lines. At the end of two years, during which he worked in secret, aided only by a trusted mechanic and a boy, his son, he constructed the first torpedo of the type that bears his name. It was made of steel, was fourteen inches in diameter, weighed 300 lbs., and carried eighteen pounds of dynamite as explosive charge. But its powers were limited. It could attain a rate of but six knots an hour under favourable conditions, and then for a short distance only. Its conduct was uncertain. Sometimes it would run along the surface, at others make plunges for the bottom. However, the British Government, recognising the importance of Mr. Whitehead’s work, encouraged him to perfect his instrument, and paid him a large sum for the patent rights. Pattern succeeded pattern, until comparative perfection was reached.

Described briefly, the Whitehead torpedo is cigar-shaped, blunt-nosed and tapering gradually towards the tail, so following the lines of a fish. Its length is twelve times its diameter, which varies in different patterns from fourteen to nineteen inches. At the fore end is the striker, and at the tail are a couple of three-bladed screws working on one shaft in opposite directions, to economise power and obviate any tendency of the torpedo to travel in a curve; and two sets of rudders, the one horizontal, the other vertical. The latest form of the torpedo has a speed of twenty-nine knots and a range of over a thousand yards.

The torpedo is divided into five compartments by watertight steel bulkheads. At the front is the explosive head, containing wet gun-cotton, or some other explosive. The “war head,” as it is called, is detachable, and for practice purposes its place is taken by a dummy-head filled with wood to make the balance correct.

Next comes the air chamber, filled with highly-compressed air to drive the engines; after it the balance chamber, containing the apparatus for keeping the torpedo at its proper depth; then the engine-room; and, last of all, the buoyancy chamber, which is air-tight and prevents the torpedo from sinking at the end of its run.

To examine the compartments in order:—

In the very front of the torpedo is the pistol and primer-charge for igniting the gun-cotton. Especial care has been taken over this part of the mechanism, to prevent the torpedo being as dangerous to friends as to foes. The pistol consists of a steel plug sliding in a metal tube, at the back end of which is the fulminating charge. Until the plug is driven right in against this charge there can be no explosion. Three precautions are taken against this happening prematurely. In the first place, there is on the forward end of the plug a thread cut, up which a screw-fan travels as soon as it strikes the water. Until the torpedo has run forty-five feet the fan has not reached the end of its travel, and the plug consequently cannot be driven home. Even when the plug is quite free only a heavy blow will drive it in, as a little copper pin has to be sheared through by the impact. And before the screw can unwind at all, a safety-pin must be withdrawn at the moment of firing. So that a torpedo is harmless until it has passed outside the zone of danger to the discharging vessel.

The detonating charge is thirty-eight grains of fulminate of mercury, and the primer-charge consists of six one-ounce discs of dry gun-cotton contained in a copper cylinder, the front end of which is connected with the striker-tube of the pistol. The fulminate, on receiving a blow, expands 2500 times, giving a violent shock to the gun-cotton discs, which in turn explode and impart a shock to the main charge, 200 lbs. of gun-cotton.

The air chamber is made of the finest compressed steel, or of phosphor-bronze, a third of an inch thick. When ready for action this chamber has to bear a pressure of 1350 lbs. to the square inch. So severe is the compression that in the largest-sized torpedoes the air in this chamber weighs no less than 63 lbs. The air is forced in by very powerful pumps of a special design. Aft of this chamber is that containing the stop-valve and steering-gear. The stop-valve is a species of air-tap sealing the air chamber until the torpedo is to be discharged. The valve is so arranged that it is impossible to insert the torpedo into the firing-tube before the valve has been opened, and so brought the air chamber into communication with the starting-valve, which does not admit air to the engines till after the projectile has left the tube.

The steering apparatus is undoubtedly the most ingenious of the many clever contrivances packed into a Whitehead torpedo. Its function is to keep the torpedo on an even keel at a depth determined before the discharge. This is effected by means of two agencies, a swinging weight, and a valve which is driven in by water pressure as the torpedo sinks. When the torpedo points head downwards the weight swings forward, and by means of connecting levers brings the horizontal rudders up. As the torpedo rises the weight becomes vertical and the rudder horizontal. This device only insures that the torpedo shall travel horizontally. The valve makes it keep its proper depth by working in conjunction with the pendulum. The principle, which is too complicated for full description, is, put briefly, a tendency of the valve to correct the pendulum whenever the latter swings too far. Lest the pendulum should be violently shaken by the discharge there is a special controlling gear which keeps the rudders fixed until the torpedo has proceeded a certain distance, when the steering mechanism is released. The steering-gear does not work directly on the rudder. Mr. Whitehead found in his earlier experiments that the pull exerted by the weight and valve was not sufficient to move the rudders against the pressure of the screws. He therefore introduced a beautiful little auxiliary engine, called the servo-motor, which is to the torpedo what the steam steering-gear is to a ship. The servo-motor, situated in the engine-room, is only four inches long, but the power it exerts by means of compressed air is so great that a pressure of half an ounce exerted by the steering-gear produces a pull of 160 lbs. on the rudders.

The engines consist of three single-action cylinders, their cranks working at an angle of 120° to one another, so that there is no “dead” or stopping point in their action. They are very small, but, thanks to the huge pressure in the air chamber, develop nearly thirty-one horse-power. Lest they should “race,” or revolve too quickly, while passing from the tube to the water and do themselves serious damage, they are provided with a “delay action valve,” which is opened by the impact of the torpedo against the water. Further, lest the air should be admitted to the cylinders at a very high pressure gradually decreasing to zero, a “reducing valve” or governor is added to keep the engines running at a constant speed.

Whitehead torpedoes are fired from tubes above or below the waterline. Deck tubes have the advantage of being more easily aimed, but when loaded they are a source of danger, as any stray bullet or shell from an enemy’s ship might explode the torpedo with dire results. There is therefore an increasing preference for submerged tubes. An ingenious device is used for aiming the torpedo, which makes allowances for the speed of the ship from which it is fired, the speed of the ship aimed at, and the speed of the torpedo itself. When the moment for firing arrives, the officer in charge presses an electric button, which sets in motion an electric magnet fixed to the side of the tube. The magnet releases a heavy ball which falls and turns the “firing rod.” Compressed air or a powder discharge is brought to bear on the rear end of the torpedo, which, if submerged, darts out from the vessel’s side along a guiding bar, from which it is released at both ends simultaneously, thus avoiding the great deflection towards the stern which would occur were a broadside torpedo not held at the nose till the tail is clear. This guiding apparatus enables a torpedo to leave the side of a vessel travelling at high speed almost at right angles to the vessel’s path.

It will be easily understood that a Whitehead torpedo is a costly projectile, and that its value—£500 or more—makes the authorities very careful of its welfare. During practice with “blank” torpedoes a “Holmes light” is attached. This light is a canister full of calcium phosphide to which water penetrates through numerous holes, causing gas to be thrown off and rise to the surface, where, on meeting with the oxygen of the air, it bursts into flame and gives off dense volumes of heavy smoke, disclosing the position of the torpedo by night or day.

At Portsmouth are storehouses containing upwards of a thousand torpedoes. Every torpedo is at intervals taken to pieces, examined, tested, and put together again after full particulars have been taken down on paper. Each steel “baby” is kept bright and clean, coated with a thin layer of oil, lest a single spot of rust should mar its beauty. An interesting passage from Lieutenant G. E. Armstrong’s book on “Torpedoes and Torpedo Vessels” will illustrate the scrupulous exactness observed in all things relating to the torpedo depÔts: “As an example of the care with which the stores are kept it may be mentioned that a particular tiny pattern of brass screw which forms part of the torpedo’s mechanism and which is valued at about twopence-halfpenny per gross, is never allowed to be a single number wrong. On one occasion, when the stocktaking took place, it was found that instead of 5000 little screws being accounted for by the man who was told off to count them, there were only 4997. Several foolscap letters were written and exchanged over these three small screws, though their value was not more than a small fraction of a farthing.”

The classic instance of the effectiveness of this type of torpedo is the battle of the Yalu, fought between the Japanese and Chinese fleets in 1894. The Japanese had been pounding their adversaries for hours with their big guns without producing decisive results. So they determined upon a torpedo attack, which was delivered early in the morning under cover of darkness, and resulted in the destruction of a cruiser, the Ting Yuen. The next night a second incursion of the Japanese destroyers wrecked another cruiser, the Lai Yuen, which sunk within five minutes of being struck; sank the Wei Yuen, an old wooden vessel used as a training-school; and blew a large steam launch out of the water on to an adjacent wharf. These hits “below the belt” were too much for the Chinese, who soon afterwards surrendered to their more scientific and better equipped foes.

If a general naval war broke out to-day most nations would undoubtedly pin their faith to the Whitehead torpedo for use in the open sea, now that its accuracy has been largely increased by the gyroscope, a heavy flywheel attachment revolving rapidly at right angles to the path of the torpedo, and rendering a change of direction almost impossible.

For harbour defence the Brennan or its American rival, the Sims-Edison, might be employed. They are both torpedoes dirigible from a fixed base by means of connecting wires. The presence of these wires constitutes an obstacle to their being of service in a fleet action.

The Brennan is used by our naval authorities. It is the invention of a Melbourne watchmaker. Being a comparatively poor man, Mr. Brennan applied to the Colonial Government for grants to aid him in the manufacture and development of his torpedo, and he was supplied with sufficient money to perfect it. In 1881 he was requested by our Admiralty to bring his invention to England, where it was experimented upon, and pronounced so efficient for harbour and creek defence that at the advice of the Royal Engineers Mr. Brennan was paid large sums for his patents and services.

The Brennan torpedo derives its motive power from a very powerful engine on shore, capable of developing 100 horse-power, with which it is connected by stout piano wires. One end of these wires is wound on two reels inside the torpedo, each working a screw; the other end is attached to two winding drums driven at high velocity by the engine on shore. As the drums wind in the wire the reels in the torpedo revolve; consequently, the harder the torpedo is pulled back the faster it moves forward, liked a trained trotting mare. The steering of the torpedo is effected by alterations in the relative speeds of the drums, and consequently of the screws. The drums run loose on the engine axle, and are thrown in or out of gear by means of a friction-brake, so that their speed can be regulated without altering the pace of the engines. Any increase in the speed of one drum causes a corresponding decrease in the speed of the other. The torpedo can be steered easily to right or left within an arc of forty degrees on each side of straight ahead; but when once launched it cannot be retrieved except by means of a boat. Its path is marked by a Holmes light, described above. It has a 200-lb. gun-cotton charge, and is fitted with an apparatus for maintaining a proper depth very similar to that used in the Whitehead torpedo.

The Sims-Edison torpedo differs from the Brennan in its greater obedience to orders and in its motive power being electrically transmitted through a single connecting cable. It is over thirty feet in length and two feet in diameter. Attached to the torpedo proper by rods is a large copper float, furnished with balls to show the operator the path of the torpedo. The torpedo itself is in four parts: the explosive head; the magazine of electric cables, which is paid out as the torpedo travels; the motor room; and the compartment containing the steering-gear. The projectile has a high speed and long range—over four thousand yards. It can twist and turn in any direction, and, if need be, be called to heel. Like the Brennan, it has the disadvantage of a long trailing wire, which could easily become entangled; and it might be put out of action by any damage inflicted on its float by the enemy’s guns. But it is likely to prove a very effective harbour-guard if brought to the test.

In passing to the Orling-Armstrong torpedo we enter the latest phase of torpedo construction. Seeing the disadvantages arising from wires, electricians have sought a means of controlling torpedoes without any tangible connection. Wireless telegraphy showed that such a means was not beyond the bounds of possibility. Mr. Axel Orling, a Swede, working in concert with Mr. J. T. Armstrong, has lately proved that a torpedo can be steered by waves of energy transmitted along rays of light, or perhaps it would be more correct to say along shafts of a form of X-rays.

Mr. Orling claims for his torpedo that it is capable of a speed of twenty-two knots or more an hour; that it can be called to heel, and steered to right or left at will; that as long as it is in sight it is controllable by rays invisible to the enemy; that not merely one, but a number of torpedoes can be directed by the same beams of light; that, as it is submerged, it would, even if detected, be a bad mark for the enemy’s guns.

The torpedo carries a shaft which projects above the water, and bears on its upper end a white disc to receive the rays and transmit them to internal motors to be transmuted into driving power. The rod also carries at night an electric light, shaded on the enemy’s side, but rendering the whereabouts of the torpedo very visible to the steerer.

Mr. Orling’s torpedo acts throughout in a cruelly calculating manner. Before its attack a ship would derive small advantage from a crinoline of steel netting; for the large torpedo conceals in its head a smaller torpedo, which, as soon as the netting is struck, darts out and blasts an opening through which its longer brother, after a momentary delay, can easily follow. The netting penetrated, the torpedo has yet to strike twice before exploding. On the first impact, a pin, projecting from the nose, is driven in to reverse the engines, and at the same time a certain nut commences to travel along a screw. The nut having worked its way to the end of the thread, the head of the torpedo fills slowly through a valve, giving it a downward slant in front. The engines are again reversed and the nut again travels, this time bringing the head of the torpedo up, so as to strike the vessel at a very effective angle from below.

This torpedo has passed beyond the experimental stage. It is reported that by command of the Swedish Government, to whom Mr. Orling offered his invention, and of the King, who takes a keen interest in the ideas of his young countryman, a number of experiments were some time ago carried out in the Swedish rivers. Torpedoes were sent 2-1/2 miles, directed as desired, and made to rise or sink—all this without any tangible connection. The Government was sufficiently satisfied with the result to take up the patents, as furnishing a cheap means of defending their coasts.

Mr. Orling has described what he imagines would happen in case of an attack on a position protected by his ingenious creations. “Suppose that I had twelve torpedoes hidden away under ten feet of water in a convenient little cove, and that I was directed to annihilate a hostile fleet just appearing above the horizon. Before me, on a little table perhaps, I should have my apparatus; twelve buttons would be under my fingers. Against each button there would be a description of the torpedo to which it was connected; it would tell me its power of destruction, and the power of its machinery, and for what distance it would go. On each button, also, would be indicated the time that I must press it to release the torpedoes. Well now, I perceive a large vessel in the van of the approaching fleet. I put my fingers on the button which is connected with my largest and most formidable weapon. I press the button—perhaps for twelve seconds. The torpedo is pushed forward from its fastenings by a special spring, a small pin is extracted from it, and immediately the motive machinery is set in motion, and underneath the water goes my little agent of destruction, and there is nothing to tell the ship of its doom. I place my hand on another button, and according to the time I press it I steer the torpedo; the rudder answers to the rays, and the rays answer to the will of my mind.”[2]

If this torpedo acts fully up to its author’s expectations, naval warfare, at least as at present conducted, will be impossible. There appears to be no reason why this torpedo should not be worked from shipboard; and we cannot imagine that hostile ships possessing such truly infernal machines would care to approach within miles of one another, especially if the submarine be reinforced by the aËrial torpedo, different patterns of which are in course of construction by Mr. Orling and Major Unge, a brother Swede. The Orling type will be worked by the new rays, strong enough to project it through space. Major Unge’s will depend for its motive power upon a succession of impulses obtained by the ignition of a slow-burning gas, passing through a turbine in the rear of the torpedo. The inventor hopes for a range of at least six miles.

What defence would be possible against such missiles? Liable to be shattered from below, or shivered from above, the warship will be placed at an ever-increasing disadvantage. Its size will only render it an easier mark; its strength, bought at the expense of weight, will be but the means of insuring a quicker descent to the sea’s bottom. Is it not probable that sea-fights will become more and more matters of a few terrible, quickly-delivered blows? Human inventions will hold the balance more and more evenly between nations of unequal size, first on sea, then on land, until at last, as we may hope, even the hottest heads and bravest hearts will shrink from courting what will be less war than sheer annihilation, and war, man’s worst enemy, will be itself annihilated.