718 



TORPEDOES. 



The effect of gun-cotton for the rupture of 

 hulls is calculated to be equal to that of 3.75 

 times its weight of gunpowder. A moored 

 torpedo of 500 Ibs. of gun-cotton will destroy 

 a strong iron-clad, if exploded 40 feet below her 

 bottom ; such a torpedo will throw up a cone 

 of water 60 feet high and 220 feet broad at the 

 base. 



Moored torpedoes of dynamite can be com- 

 bated by countermining. Experiments were 

 made in Denmark about three years ago, which 

 proved that dynamite torpedoes cannot be 

 planted near together in the water without 

 exploding simultaneously. A charge of 150 

 Ibs. of dynamite in 10 feet of water will dis- 

 charge, by the vibrations imparted to the water, 

 all the dynamite within a distance of 300 feet, 

 upon its explosion. Gun-cotton is also very 

 sensible to vibrations communicated to the 

 water by the same material. It was noted, in 

 the same series of experiments, that a current 

 of electricity from a powerful electric machine, 

 traversing one of a bundle of wires, will in- 

 duce secondary currents in the other wires, 

 which will discharge other torpedoes than the 

 one meant to be operated. This fact has led 

 to a plan of defense by which a whole system 

 of mines may be cleared by connecting the 

 wire of one of them with a frictional electric 

 machine. By exploding countermines off a 

 man-of-war the danger of sunken dynamite 

 torpedoes can certainly be averted. A harbor 

 entrance can be cleared by suspending counter- 

 mines from buoys, and, after letting them drift 

 with the wind or tide into the desired position, 

 discharging them by electricity ; 500 Ibs. of 

 gun-cotton is calculated to be sufficient to de- 

 stroy all submarine mines within the radius of 

 120 yards. Still more formidable than torpedo 

 mines are the modern locomotive torpedoes, 

 the principal forms of which are described be- 

 low. The old style of offensive torpedoes, 

 which were floated down against their object 

 and fired by concussion, clock-work, or time- 

 fuses, were too uncertain in their action and 

 too easily detected and avoided to require any 

 special safeguard. The modern submerged lo- 

 comotive torpedoes and torpedo-launches are 

 so perfectly under the control of their opera- 

 tors, so fatal in their action, and so swift in 

 their movements, that it is thought by many 

 that they have rung the kuell of the expen- 

 sive, mighty iron-clads of modern navies. Un- 

 der the conditions when they attack they can 

 hardly be avoided if seen. They demand spe- 

 cial means of protection ; the most promising 

 modes of defense yet devised are described be- 

 low. The Whitehead fish-torpedo, the Harvey 

 towing-torpedo, and the Lay torpedo-boat are 

 all submarine, and are operated at a distance. 

 The Whitehead is discharged, with a swift, un- 

 erring aim, at its object ; the Lay submarine 

 boat is steered and operated by electricity ; the 

 Harvey torpedo is guided by the craft which 

 tows it, and shows no sign of its approach ; 

 the torpedo-launches can be sent out without 



a crew, and steered by electricity, but gener- 

 ally they are manned. 



The Harvey torpedo, invented by Command- 

 er Harvey, of the British Navy, in 1862, is 

 charged with gunpowder, which is ignited by 

 a percussion bolt of detonating powder. The 

 torpedo is incased in a wooden box, which is 



FIG. 2. HARVEY TORPKDO. 



buoyant, although cork buoys are sometimes 

 employed in addition. This torpedo can be 

 lowered from a ship's deck by means of a 

 windlass, and is very useful for a vessel which 

 is pursued by a hostile ship. It can be dropped 

 down to the surface of the water in such a po- 

 sition that it will either drift or remain in the 

 course of the vessel giving chase. On being 

 struck by the hull of the ship, a lever is pressed 

 down, which sets in motion the mechanism 

 which discharges the detonator. The charge 

 is sufficient to stave a hole in a vessel's side or 

 bilge. While being towed, the torpedo-chest 

 always floats on the surface ; but it can be bal- 

 lasted, so that it will sink, upon slackening the 

 wire tow-line, under the hostile vessel, and 

 can be fired against the ship's bottom, either 

 by the mechanical firing-bolt, which operates 

 by contact, or also by electricity. There are 

 two different forms of case, one for the star- 

 board and one for the port side. 



The Whitehead fish-torpedo is a steel cylinder, 

 shaped like a cigar, and pointed at both ends ; 

 it is 14 to 19 feet in length, and 14 to 16 inch- 

 es in diameter. The interior is divided into 

 3 compartments : in the head is placed the 

 explosive, some 350 Ibs. of gun-cotton ; in the 



FIG. 3. LUPPIS WHITEHEAD TORPKDO. 



centre is a chamber holding the propelling and 

 regulating machine; in the tail part is con- 

 tained the supply of compressed air whicli 

 works the engine. The diminutive engine 

 which propels the torpedo has a capacity of 



