In the plate, A represents a patented interchangeable boiler, in which either hydro-carbonate fuel or caustic soda can be used, in both cases steam being the motive power. The interior boiler for the use of the caustic soda is surrounded by a jacket, into which the steam exhausted from the engine can be used before it becomes so saturated as to create a back pressure on the engine, that is, for a period of twelve hours. When this limit is attained, and the surface is reached, the soda can be blown off into an outer receptacle provided for the purpose, and then reheated and recharged. The hydro-carbon fuel is ordinary mineral oil, carried in tanks of sufficient capacity for a surface run of a week. It may be emphasized as an important fact that this method of exhausting into the jacket of the boiler avoids the possibility of any bubbles appearing on the surface, as was notably the case with the earlier Lay boats.
Before diving, the caustic soda, which has been already heated by the combustion of the oil to the proper degree, acts in place of the ordinary fuel, thus constituting a sort of perpetual motion, until the point of saturation is reached, and back pressure in the engine results.
The boat, when on the surface, is run with the oil fuel, but as soon as it becomes necessary to dive this fire is extinguished, the after-hatch is opened by unlocking the door of the bulkhead separating the after from the bulkheaded end of the vessel, and by a system of fans the hot air from the fire-room is driven outboard. Then the after telescopic hatch is reefed and secured, the soda is thrown from the receptacle where it has been heated into the jacket of the caustic-soda boiler, the fires are put out, the smoke-stack is taken in and securely fastened, and the machinist, leaving the engine-room, goes through the bulkhead door into the forward compartment, where he has complete control of the machinery and boiler by means of a duplicate set of gauges and levers. In case of an attack, the man detailed for operating the main torpedo is left in the after compartment, where he has access to that weapon and to the buoy, reel, and other mechanical appliances employed in its operation.
The helmsman, who controls the steering apparatus that governs the horizontal and perpendicular rudders, also operates with his feet the levers which are connected by links to the throttle that supplies steam to cylinders K K. These last function like the Westinghouse brake, and are connected with pistons to the cylinders J J. Through their agency water is at will admitted into or forced out of the larger receptacles, either from one end or from both ends simultaneously. The effect of discharging water is of course to increase the buoyancy of the vessel; and of admitting it, to decrease this quality so that without changing structural weights the boat is enabled to rise or sink perpendicularly, or, by admitting more water in one end than in the other, to take a downward or an upward course. Though this does away with the necessity of the horizontal rudder, it is kept as an additional resource for steering. In case of accident to the connecting pipes or machinery the vessel is supplied with water receptacles and hand-pumps, which are able to govern its submergence so that should all other mechanism break down the boat is so completely under the control of the operator that it can at all times be brought to the surface. As an additional safeguard, there is on the outside of the boat a quantity of ballast which can be readily detached by the arms or sleeves previously described, and so effectively that the reserve buoyancy thus gained will alone carry the boat to the surface.
In addition to the main torpedo and buoy resting in the cylindrical apertures aft, other torpedoes, connected by spans, are carried on deck. The method of their employment in attack is to go under the body of the vessel athwartship, and to liberate them. As they are fitted with magnets, they will, it is claimed, when freed, attach themselves to the bilges of the enemy’s vessel, while the Peacemaker can continue her cruise and let them act automatically, or, backing off to a distance greater than the depth of water in which she then is, safely explode them by conventional electrical appliances. With the increased speed of the present boat there are various methods of attacking vessels of war when under way, among them one which is somewhat similar to that described above.
The Peacemaker, when under the body of the vessel athwartship, would liberate a buoy, B, that is connected with a torpedo, T, by a chain, the length of which depends upon the depth beneath the buoy the torpedo is desired to float. The steel tow-line to the torpedo is payed out from reel G to a sufficient length, and then by going ahead with the boat the torpedo is drawn close under the opposite side of vessel from buoy B. In this position the torpedo can be exploded by electricity.
If necessary, by liberating buoy B, while crossing the bow on the starboard side of the fore-foot of a vessel, the forward motion will draw the torpedo, T, close in to the opposite side; then, by a system of push-pins on the torpedo, the operator learns that it is in close contact and ready for explosion by electricity. Should the enemy’s vessel be at anchor the tide can be employed for the purpose of bringing the buoy on one side of the vessel while the torpedo is on the other.
The boat is supplied with the ordinary incandescent lights, or apparatus for lighting the interior for night attacks.
TORPEDOES.