3.—It may be used as a tug or towing boat to take out a number of torpedoes, which may be sunk and exploded when desired.
4.—It may be used in connection with certain apparatus to clear away obstructions found to prevent the entrance of ships into harbours, and it may also be used to clear harbours of mines, &c.
Launching the Lay Torpedo Boat.—For facilitating the launching and controlling of the Lay torpedo boats, a structure or submarine fort is used. This structure may be square, or oblong, and may be made to carry any number of the torpedo boats. The body is constructed of plate or sheet iron of suitable strength and stiffened with angle iron, or otherwise, and divided longitudinally or transversely into watertight compartments, into which the water is admitted to sink the said structure. At the top or upper side, cylinders or tubes are placed, each of which is capable of containing and launching one of the torpedo boats. At the forward end of each tube is a door, or cover secured to a rod or shaft fitted to turn in suitable bearings; this rod or shaft is provided with an arm which is connected to the piston rod of an engine worked by gas contained in a reservoir, or by other suitable means. The slide or other valve which controls the admission of the gas, &c., to this engine is arranged in connection with electro magnets, connected by a suitable cable with a keyboard on shore, or wherever the operator's station may be. By sending an electric current through this cable in one direction through the electro magnets, the door is closed; and by sending such a current in the opposite direction it is opened. The cables carried in the torpedo boats, and through which the mechanism on board each torpedo boat is operated and controlled, are also in this case connected with the keyboard, which must be provided with a number of sets of pole changers and switches, or equivalent devices, corresponding with the number of boats to be controlled by means of the said keyboard.
This apparatus will form a very convenient adjunct to fortifications or stations liable to be attacked by sea. The said fort may be prepared for use by placing torpedo boats in the said tubes, and may be kept floating until the enemy's ships have arrived closely enough to permit the determination of the point where the said fort can be most advantageously located for operating against the said ships. The fort is then towed to this point, or taken as near as possible thereto on rails, and towed the remainder of the distance. It is then submerged, and will be ready for immediate operation. The said fort is provided with suitable valves for the admission of water to sink the same, and with means for forcing in air through the pipe P* to expel the water when the fort is to be raised.
When it is desired to launch either of the said torpedo boats, the door of its tube or cylinder is first opened by sending a current through the cable that controls the door, as above described. Then the current is sent through the boat's cable to start her propelling engines. The said boat will then emerge from the cylinder or tube and will rise to the surface, or as near the surface as may be desired, and may then be directed and controlled by the operator at the keyboard, as previously described. And one after another of the said torpedo boats may be thus launched and exploded, without giving to the enemy any clue to the point or position from which they are being sent.
LAY'S LOCOMOTIVE TORPEDO.
Launching the Torpedo from a Ship.—The method of launching the Lay torpedo boat from an ironclad or other large ship is shown at [Fig. 130]. The tubes or cylinders S in which the torpedo boats A are held are, in the apparatus shown at [Fig. 130], closed at their inner ends by plates, or covers S1, which are provided with suitable water-tight and insulating packing boxes S2 for the passage of the electric cables of the said torpedo boats, each cable being connected with the keyboard, which is placed in any convenient part of the ship, and at their outer ends the said tubes are furnished with strong and well-fitted slide valves, or sluice gates S3, which are opened by screws, connected by gearing with a hand wheel, and shaft S4, S5, for the admission and exit of the said torpedo boats. Also these cylinders are provided with packing pieces at their sides, arranged to be pressed by screws or otherwise up to the sides of the torpedo boats in these cylinders, and thereby hold them firmly and immovably in rough weather.
The Method of Sinking and Raising a Lay Torpedo Boat.—The apparatus by which this is effected is shown at [Fig. 131], which is a longitudinal section of a portion of a torpedo boat. The hull A of the torpedo boat is provided with a water chamber l, which has holes or apertures l1 in the bottom of the same, and is also provided with an air cock at l2. In connection with this chamber is arranged a small cylinder m, provided with a piston m1, whose rod m2 is attached to the lever of the said cock. A spiral spring m3 is provided to resist the inward movement of the said piston. The said small cylinder m is connected by a pipe m4 with a valve chest, in which is arranged a slide valve m5. The said slide valve is connected by a rod or rods to the lever or levers m6, whose fulcrum is at m*, and the said levers are connected by the links or rods m7 with the armatures of electro magnets n, which are included in the circuit of the cable, whereby the boat is controlled from the keyboard at the station; o is a pipe extending from the said valve chest to the aforesaid water chamber l; p is a feed pipe by which gas is conducted from the reservoir or generator to the valve chamber.