Torpedo Boats
small vessels built for speed and fitted with tubes for firing torpedoes by either compressed air or gunpowder. They are of two classes: those with powerful engines designed to steal on an enemy under cover of darkness, and those which can be used on the surface or submerged to do their work unseen beneath the water. The first torpedo boat was built about 1873, by Thornycroft, of England, for the Norwegian Government. This had a speed of 15 knots an hour, which has been raised in subsequent vessels of the kind to over 30 knots. The first of the present class of torpedo boats was built by Thornycroft in 1887 for the Spanish Government. The torpedo boat destroyer does not differ essentially from the torpedo boat, except in its greater speed and its power, owing to its greater weight, to maintain that speed in the face of a considerable sea. Its armament is also heavier and its guns of longer range.
In the American-Spanish War, Admiral Cervera had three torpedo boat destroyers in his ill-fated squadron and all were destroyed by the American ships, two of them, the "Pluton" and "Furor," at Santiago, by the converted yacht "Gloucester." They form a useful protection to larger ships in battle, and in the World War were employed in great numbers by the combatants. The torpedo boat destroyer developed from the torpedo boat. See SUBMARINE MINES AND NAVIGATION.
TORPEDO-BOAT DESTROYER, a torpedo boat of a most formidable kind, designed for the destruction of ordinary torpedo boats. The destroyers are usually armed with one 12-pounder gun and from three to five 6-pounder guns, besides their equipment of torpedoes, and carry a crew of four officers and about 40 men. They are capable of 30 knots an hour, and, as they carry from 70 to 100 tons of coal, can make a voyage of 1,300 to 1,500 miles without recoaling.
The World War introduced many improvements in destroyers. They performed invaluable services in naval operations. In the battle of Jutland the German destroyers raised a smoke-screen before the German fleet, which enabled the German admiral to withdraw his ships from immediate danger from British guns. See TORPEDO BOATS. TORPEDOES TORPEDOES. The torpedoes known to modern warfare are all automobile; that is to say, they run by their own power, differing in this respect from projectiles fired from guns, which otherwise they rather closely resemble. And not only do they run by their own power, but they carry a complicated mechanism by which they steer themselves, regulate the depth at which they run, and render themselves harmless after a certain length of time if they fail to hit their mark. a Torpedoes of various forms have been known and used for several centuries, but the automobile torpedo of today is essentially a development of the last fifty years, having been invented about 1870 by an Englishman, Whitehead, who, failing to secure recognition from the British naval authorities, took his invention to Austria, where it was at once adopted.
It was slow in making its way in other countries, and even as late as the beginning of the World War, in 1914, was regarded in many quarters as of no great practical value. It accomplished nothing in the Spanish-American War of 1898 and little or nothing in the Russo-Japanese War of 1904; and even those who had most faith in its possibilities were unprepared for the manifestation of its efficiency given by the Germans in the first months of the World War and thereafter. A large part of this efficiency was due, of course, to the remarkable development of the submarine, a development which at that time had been carried much farther in Germany than elsewhere. But the outstanding feature of the submarine campaign was the thoroughness with which the two factorsthe torpedo and submarine had been adapted to each other. Both the British and the American navies took the lessons of the war to heart and both have now, a little late, carried both the torpedo and the submarine far beyond the point attained by the German navy at its best.
Figure 1 shows the principal features of the torpedo. At the forward end is the war-head, A, carrying the explosive charge, 600 pounds of gun-cotton or trinitro-toluol. The fuse by which the charge is exploded on striking projects from the nose of the war-head but is rendered inactive until the torpedo is fired by a safety device which is released by pressure of the water. For purposes of drill the war-head is replaced by an exercise-head made of soft metal which collapses when it strikes a hard surface, thus indicating that the target, often the side of a friendly battleship, has been hit.
TORPEDOES Immediately abaft the head is the airflask, B, with air under high pressure and fur- B, a large compartment charged nishing the motive power for the engine, D. In a pipe leading from the air-flask to the engine is the starting-valve, connected with a small lever on the outside propellers, of which there are two, RR, runs through the after-body, E, to the gines are still used abroad. The shaft pedo is a turbine, but reciprocating enmatically when the torpedo is fired. The engine in the latest American torpedo is a turbine, but reciprocating engines are still used abroad. The shaft runs through the after-body, E, to the propellers, of which there are two, RR, in tandem, one being keyed to the shaft and the other to a sleeve around the shaft and connected with it by a beveled gear. The propellers turn in opposite directions, one right, the other left, and and, in an extreme case, strike the ship est difference in their action would cause the torpedo to diverge from its initial course and might make it run in a circle and, in an extreme case, strike the ship from which it had been fired.
The rudder, R, abaft the propellers, is placed horizontally, not vertically, its AIR FLASK A B B TORPEDOES pedo. The essential feature of this dethe water, which varies with every variavice is the utilization of the pressure of tion in the depth, to actuate the horizonsary. The figure shows the immersion- the torpedo up or down, as may be necessary. The figure shows the immersionchamber (water-tight), and the engine rated by a water-tight bulkhead. In the the torpedo up or down, as may be necesimmersion-chamber is a sleeve carrying the hydrostatic-piston, which is held by a spring in contact with a flexible diacompartment (open to the sea), sepaphragm forming a part of the watertight bulkhead. The tension of the spring pressure of the water for any desired depth. If we suppose the spring to be given a tension equal to that of the water at a depth of 15 feet, the piston will can be varied to correspond with the remain at rest when the torpedo ning at that depth. If the torpedo rises, the pressure of the water on the flexible diaphragm will be less than the tension to the right, carrying with it a rod which is attached to the rudder, and steering to the right, carrying with it a rod which of the spring and the piston will move diaphragm will be less than the tension bedo is runedo of the spring and the piston will move IMMERSION CHAMBER α AFTER BODY AFTER BODY XC D RUDDER RUDDER WAR HEAD α ENGINE COMPARTMENT
DIAGRAM OF TORPEDO-FIG. 1 ENGINE purpose being to steer the torpedo up and down, not to right and left. Very small vertical rudders are used in conlater, but these are not shown in the nection with the Gyro gear, described later, but these are not shown in the drawing.
R PROPELLERS the torpedo down. If it dives too deep, the balance of pressure is disturbed in is steered up. And so on, until the torthe balance of pressure is disturbed in the opposite direction and the torpedo which the spring is adjusted. the opposite direction and the torpedo 12,000 yards (six miles) and at this range a stationary target of the length of a dreadnaught can be struck three The range of the most powerful tortimes out of four. Naturally the conditions are greatly modified and the ac- The brains of the torpedo are in the immersion-chamber, C, between the airflask and the engine compartment. Here immersion-chamber, C, between the air- The brains of the torpedo are in the is placed the mechanism by which the torpedo is governed in many ways. A gyroscopic device opposes any tendency torpedo is governed in many ways. A is placed the mechanism by which the to deviate from the initial course. A range a stationary target of the length 12,000 yards (six miles) and at this pedoes in use in 1921 is approximately A scribed depth, usually from 15 to 20 feet.
A soluble certain time and causes the torpedo to ble plug opens a valve after a sink if it has missed its mark. An automatic throttle-valve keeps the air pressure constant during the discharge of the air-flask, insuring a uniform speed throughout the run. only the depth-regulator, Figure 2, will be described, this being, perhaps, the Of these devices, most characteristic feature of the torthe firing ship and the target ship are sunk by German torpedoes during the usually less than a thousand yards. moving at considerable speed. The ships war were all attacked at short range, battleships, all of which are fitted with war were all attacked at short range, sunk by German torpedoes during the er craft-destroyers and submarineselaborate arrangements for the purpose, While torpedoes may be launched from the high speed of the destroyer and the TORPEDOES invisibility of the submarine giving such a craft a great advantage in the use of a weapon like the torpedo, which is essentially a weapon of surprise. One of the developments promised for the future is a torpedo airplane, which shall carry a torpedo, with arrangements for launching it from a height of several thousand feet while flying at full speed. There is promise also of a torpedo which can be controlled from the firing ship or from a shore station, by radio. Lastly may be mentioned a possible combination of these two plans, the torpedo being IMMERSION CHAMBER (WATER-TIGHT) GUIDE SLEEVE TORQUEMADA called from its having housed some survivors from the Armada); and St. Michael's Chapel, on a hilltop, is thought to have been connected with the abbey.
St. John's Church, by Street, is a striking early English edifice; and other buildings are the town hall, museum, and theater. Torquay is a great yachting station; its chief industries are the working up of Devonshire marbles and the manufacture of terra-cotta. Pop. about 39,000.