THORNICROFT'S BOAT APPARATUS FOR FISH TORPEDOES.
The Whitehead fish torpedo costs about 380l., while the Woolwich one costs only 300l.
The Lay Torpedo Boat.—Priority of invention of this torpedo was on the 13th of June, 1873, awarded by the Commissioners of Patents to Mr. John Louis Lay, several other persons having claimed the invention, among whom was Colonel Von Scheliha, an officer of the Russian army.
This locomotive torpedo, or more properly called torpedo boat, has been for several years adopted by the American government, during which time it has undergone a series of exhaustive experiments, which has proved it to be a most valuable and efficient weapon of offence and defence. Lately the Russian government have adopted it, and intend using it extensively in the defence of their harbours, &c.
General Description of the Torpedo.—At [Fig. 122] is shown a longitudinal section of a Lay torpedo boat constructed and provided with guiding and controlling apparatus, and with means for propelling it by ammoniacal gas. [Fig. 123] is a horizontal section of the same; A is the hull or body of the boat, which has conical ends A1, A2, and is formed of thin plate iron, or steel, or other suitable material. The section in the end A1 forms the magazine containing the charge of dynamite or other explosive material; A3 is the section containing the gas reservoir or holder; the compartment A4 contains the apparatus for holding and paying out the electric cable; the compartment A5 in the end A2 contains the motor engine, the steering apparatus, and other parts to be hereinafter described. All of these compartments or sections are separated from each other by means of air-tight bulkheads A6. The torpedo boat may be propelled by means of a single screw, double screw, or two screws. In the latter method, which is shown at [Fig. 122] and [123], the propellers B and C are made to revolve in opposite directions; the shaft D of the propeller B is hollow or tubular, and the shaft E of the screw C passes through the same; these screws are actuated by an engine shown at F. H, H are the horizontal rudders, or side wings, two forward and two aft; these wings are mounted on shafts or spindles passing transversely through the boat; these rudders may be set to occupy a horizontal position, or a more or less inclined position in the proper direction, to cause the submerging of the boat by the action of the water on the said rudders as the boat moves forward, and they are adjusted before starting. N, N are two guide rods, one aft and one forward, which project up from the boat to enable the operator to determine its position at any part of its run, and in the case of a night attack they are provided with lights; the said rods can be raised or lowered at the will of the operator. Q is the electric cable, which affords a medium of communication between the operator on shore, &c., and the torpedo boat, whereby it may be started, stopped, steered, fired, and has her position ascertained; this cable is carried in the boat in a coil arranged longitudinally in the air-tight chamber A4 in the reel frame R, and is payed out as the torpedo progresses through a tube S, projecting aft under the boat and beyond the rudders and propellers, so that the said cable will not be fouled by the same; or it may be payed out through a hollow shaft in the centre of the boat. One end of this cable is connected to a keyboard at the station on shore or on board of the ship or other structure from which the torpedo boats are controlled. This keyboard is provided with a suitable battery or other means for generating the electric current, as hereinafter described.
The said cable is composed of several wires, each of which is insulated from the others. One of these wires is connected with the mechanism for starting and stopping the boat, one is connected with the steering apparatus, one serves for indicating to the operator at all times the exact position of the rudder, one is connected with mechanism for elevating and depressing the said guide rods, and one serves for firing the charge in the magazine.
The motive power for effecting the necessary movements of the mechanism or apparatus in performing the above operations is obtained from the aforesaid engines, which are provided with suitable valves arranged in combination with electro magnets, shunts, and the devices connected with the said wires of the cable, as hereinafter set forth.
This form of cable has since been replaced by one which consists of two wires only, the one for performing all of the necessary operations, exclusive of the firing or exploding of the magazine, and the other exclusively for this latter purpose. This improvement is effected by employing a series of relays or resistance coils, or a multiple, or compound relay in the boat. The advantages gained by this improved form of cable are:—