We now come to the class of moving torpedoes which is most in use, the automobile or 'fish' type. There are many varieties, but only three are actually in service, the 'Whitehead, Schwartz kopf, and Howell. The first and second of these The Howell torpedo resembles the Whitehead in all its features except the propelling mechan ism. The forward compartment is the war-head. Next in rear is the propelling compartment, then comes the buoyancy chamber containing the depth regulating mechanism, and lastly, the after compartment which contains the steering mechanism for both horizontal and vertical rud ders. The source of propelling power is a heavy fly-wheel so designed as to have most of its weight near the periphery. By means of a steam turbine connecting to a clutch projecting barely through the shell of the torpedo this wheel is spun up until its speed is 9000 revolutions per minute or 150 revolutions per second. This gives ample power for a long and fast run if it could all be utilized, but up to the present it has been found impracticable to get the power to the propellers fast enough. The propellers are not on one shaft as in the Whitehead, but on two, each connecting to shafts driven by gear ing from the fly-wheel. In addition to the sim plicity of the form of power, the fly-wheel acts as a gyroscope and strongly resists any force tend ing to force the torpedo out of the plane in which it was originally launched. The Howell is still in service in the United States Navy, but the development of the Obry gear in the Whitehead has so improved the directive force of the latter that its otherwise superior qualities have caused it to displace the Howell in all new ships.
It is not unlikely that attempts to employ torpedoes or mines were made in the early days of gunpowder, but the first occasion on record in which they were used was in 1585, when an Italian engineer by the name of Gianibelli (q.v.) partially destroyed a bridge across the Scheldt at Antwerp by means of small vessels each carrying a considerable quantity of gunpowder which was exploded by clockwork mechanism. Nothing more is heard of torpedoes until 1730, when the French scientist Desaguliers made some experi ments with some of the rocket type which were fired under water and with which he is said to have destroyed several boats. The first torpedoes to be used in war against ships were designed by an American, Capt. David Bushnell, who also built the first submarine torpedo boat, though not the first submarine boat. After making nu merous successful experiments Captain Bushnell made three attempts to destroy British men-of war. In the first, Sergeant Lee used Bushnell's submarine boat (see TORPEDO BOAT, SUBMARINE, for description and illustration), and actually got under H.M.S. Eagle, but failed to attach and explode his torpedo, owing to inexperience in handling his novel craft and the bluntness of the screw he tried to use. The second attack was made on 11.1\-1.S. Ccrbcrus by drifting torpedoes; this failed, but one of the torpedoes was picked up by the. crew of a prize schooner astern of the Cerberus and exploding on board, killed three men, destroyed a boat, and injured the schooner. The fourth attempt, also at New London, was the celebrated 'Battle of the Kegs,' and it failed because the British ships had hauled in to the wharves to avoid the ice; but it created much confusion and alarm among their crews. The
next man to take up torpedoes seriously was Robert Fulton, who began his experiments on the Seine in 1797. His first attempts were chiefly failures, but in 1801, at Brest, he destroyed a small vessel with a submarine mine containing twenty pounds of gunpowder. This is believed to be the first vessel sunk by a torpedo, but he afterwards succeeded in several instances, and where the attack failed it was owing to the movement of the vessel from above the torpedo and not to defects in the torpedo. In one in stance a British brig was destroyed by two torpedoes made by him containing 180-pound charges of gunpowder fired by clockwork. In 1812 and 1813 another American, Mr. Mix, made unsuccessful attempts to blow up British ships. In 1820 Captain Johnson, an English man, with a submarine boat attached a torpedo to the bottom of a vessel and exploded it. In 1829 Colonel Samuel Colt began his torpedo inves tigations, developed the electric firing of mines in 1842, using in one instance wires forty miles long with complete success.
In the Civil War in America the torpedo came quickly to the front as a serious weapon. The few ships of the Confederates offered little op portunity for the use of torpedoes by the Fed erals, but the great fleet of the latter and the necessity which often compelled the vessels to operate in narrow waters gave a multitude of chances which their enterprising antagonists were quick to seize. The unsuccessful attempts were hundreds in number, but during the course of the struggle 7 Federal armor-clads, 9 gun boats, 6 transports, and l cruiser were sunk or destroyed, and 2 armor-clads, 3 gunboats, transport, and 1 large cruiser were seriously in jured. Of the latter, 1 cruiser and 1 armor clad were attacked„ by boats using spar tor pedoes. The only important Federal success was the destruction of the armorclad Albemarle by Lieutenant Cushing, who also used a spar torpedo.
While all this was going on Captain Lupuis of the Austrian Navy and Mr. Whitehead began the development of the movable torpedo. The idea of a small, self-propelled boat carrying an ex plosive charge and directed from a distance had occurred to Captain Lupuis in 1S60, but it was not until 1864 upon his association with 1\ar. Whitehead that any craft of the sort were built. Mr. Whitehead, who was an English engi neer acting as superintendent of engineering works at Fiume, took hold of the project with great interest. He soon gave up the plan of using directing wires, and bent his energies to the development of a completely automatic de vice. In 186S the first official trial was held before a board of Austrian officers, and its report resulted in the adoption of the weapon in the Austrian service, although the speed at tained was only about seven knots. From this time to the present the improvement has been continuous, the speed rising to 35 knots and the directive force becoming almost absolutely cer tain when the conditions are favorable. A]] na val powers now use the Whitehead or its equiva lent., the Schwartzkopf, and many (including the United States) have purchased the right to manufacture them.