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]
[2] Pearson’s Magazine.
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.