TORPEDOES. 



719 



40 horse-power, although its weight is only 35 

 Ibs. The mechanism can be regulated so that 

 the boat will travel through the water at any 

 required depth, from 1 to 30 feet below the 

 surface. The tension of the compressed air is 

 800 Ibs. per square inch, but the air-chamber 

 is tested to 1,200 Ibs. ; the charge is sufficient 

 to propel the torpedo 2iO yards at the velocity 

 of 24 knots an hour, or 1,000 yards at the rate 

 of 20 knots an hour. The torpedo is driven for- 

 ward by two small three-bladed steel screws, 

 right and left handed, placed behind. The case 

 of the torpedo is of specially prepared steel, 

 and the screws are made from the finest qual- 

 ity of metal. The torpedo is fired from an im- 

 pulse tube, which is fitted into a post below the 

 water-line ; or it may be fired from the deck, 

 ainking immediately to the depth at which it 

 is set, and then going straight to its target, 

 the rate at which the vessel from which it is 

 discharged is sailing making no difference in 

 the accuracy of the aim, which is so perfect 

 that a vessel, distant 1,000 yards, can be hit 

 every time, though sailing 10 or 12 knots an 

 hour. The torpedo is made to sink and remain 

 during its travel at a certain depth below the 

 water-line by means of an horizontal balance- 

 rudder ; the fish is generally ballasted to swim 

 about 8 feet below the surface, and charged for 

 a journey of 1 to 1J mile- It is so contrived 

 that, if it fails to hit the object-vessel, it will 

 rise to the surface, and, having been rendered 

 harmless by a guard-trigger, can be recaptured ; 

 or it can be constructed to sink to the bottom 

 after running its course, and explode at half- 

 cock. The charge of explosive is sufficient to 

 rend a hole in a ship's side of 70 feet area. 



These torpedoes are manufactured by Messrs. 

 Whitehead & Co. at Fiume, on the Mediterra- 

 nean, and are purchasable for all the world, 

 like Krupp's cannons. The first effective fish- 

 torpedo was made in 1867. The secret of their 

 construction has been sold to the British Ad- 

 miralty. 



TIG. 4. WOOD AND LAY TOKPEDu. 



The Lay torpedo, or submarine torpedo- 

 boat, is the invention of Mr. Lay, of Buffalo, 

 and has been purchased by the United States 

 Government. It is a cylindrical boat, with 

 conical ends, carrying a spar-torpedo, or con- 

 taining in its forward end a sufficient quantity, 

 say 100 Iba., of explosive. The motive power 

 is supplied by an engine worked by carbonic 



acid gas, which drives a screw-propeller. The 

 liquid to be expanded into gait is stored in 

 the forward section of the cylindrical body. 

 There is a coil of rope in the interior, which 

 connects it with the point from which it Las 

 been dispatched. The torpedo can be launched 

 from shore as from a ship. All its movements 

 are within the control of the operator on shore, 

 who steers it, regulates its machinery, and ex- 

 plodes it by means of a compact electrical bat- 

 tery and key-board. The course of the boat is 

 shown to the operator by a small flag which rises 

 above the surface of the water. Experiments 

 were made with the Lay torpedo at Cleveland, 

 Ohio, in the early part of the summer, which 

 showed that the course of the boat was per- 

 fectly under control; the speed attained was 

 at the rate of 9 miles an hour around a goal 

 half a mile from shore. 



A locomotive torpedo, called the " rocket- 

 torpedo," designed by Mr. Macdonald, in Eng- 

 land, is said to have three times the velocity 

 of the Whitehead torpedo, and a range of over 

 two miles. The rocket-torpedo is cigar-shaped ; 

 it is made of various sizes, according to the 

 length of its intended course, and the amount 

 of explosive in the charge. It is discharged 

 from a skeleton-tube, or trough, by means of 

 an electric fuse ; it may be sent from a boat or 

 from the side of a man-of-war with equal fa- 

 cility. Its motive power is derived from the 

 gas developed in the slow combustion of some 

 composition which evolves a rapidly expanding 

 gas. It has more than all the merits of the 

 Whitehead torpedo, it is claimed, without the 

 danger of compressed air, and can be fired with 

 the utmost accuracy, the speed not diminishing 

 in the latter part of the course. Its >-t, also, 

 is only one-tenth that of the Whitehead. 



The famous Thornycroft launches, fitted for 

 spar, fish, and other torpedoes, are redoubta- 

 ble aids in torpedo-warfare. The first of the 

 fast torpedo-boats made by the firm was the 

 river-launch, built in 1871, which, although 

 less than 60 feet long, 

 could make 16$ knots an 

 hour. Boats were soon 

 ordered for the Nor- 

 wegian, Swodinh, and 

 Danish Governments, of 

 somewhat greater size, 

 engined with about 90 

 horse-power, in which 6 

 air- comportments were 

 introduced for safety ; 

 they were armed with 

 to wing-torpedoes, wboM 

 course was on one side of 

 tin- boat, like the ilarre.r. 

 Larger launches were then made for France and 

 Austria, of 67 feet length and 8 feet 6 inches 

 beam, draught 4 feet 8 inches, and indicated 

 horse-power 200, capable of a upocd of over II 

 knots an hour. These were armed with upar- 

 torpedoes, to be fired by electricity or upon 

 contact at will of the operator. The French 

 boata steamed across the Channel in the open 



