The original submarine monitor Peacemaker is well known through its trials on the Hudson River in 1886, but since then so many improvements have been made in the direction of increased efficiency that it is confidently expected the boat just designed will surpass its former successes. It must be understood in the beginning that its essential principle remains the same, all the important improvements being the outgrowth of the experience gained in previous experiments.
Broadly defined, the new craft has a midship section, which through its high centre of buoyancy and low centre of gravity gives great stability of form, or, to make it plain to the non-technical reader, it differs from the ordinary cigar and tortoise shaped boat in being more nearly like the section of a pear, the apex of which forms the keel. Its longitudinal section is not unlike the form generally used, though the lines are such as have been found to give the form of least resistance and the highest speed.
It is built of steel, with frames and spacings sufficient to stand the pressure of the lowest depth to which the boat is or can be expected to go. The old dimensions were: length 30 feet, depth 7 feet, and beam 8 feet. In order to obtain increased speed the present vessel will be 50 feet in length, 8 feet in beam, and 8 feet in depth, with a displacement of from thirty-five to forty tons, or an amount sufficient to carry the weights of the interchangeable boiler, of the sixty horse-power engine, and of the provisions and fuel necessary for a surface cruise of one week, and, when necessary, for a constantly submerged cruise of twelve hours.
The advantages claimed for the new boat are that she is so self-sustaining as not to need the assistance of any other vessel; that she is not an accessary, but has in herself all essentials of defence; and that she answers all possible necessities for submarine work of any kind whatever, whether in peace or war. The increased speed will, it is hoped, give her power to attack modern vessels under way. When submerged, as was proved last summer, she sent no bubbles of air to the surface, and had neither a wake nor a wash to militate against the possibilities of an absolutely secret attack. Besides these advantages, the boat is said to be a safe surface-cruising vessel, forming no target for the destructive action of an enemy’s attack, and at the same time having a capacity for disappearing so readily under water and avoiding the possibility of discovery that the enemy will be unable to tell when, where, or how the assault upon him may be made.
As in a former trial an accident proved the danger of an exposed conning-tower, the Submarine Monitor Company have provided a fin or guard for protecting the new helmsman’s lookout and companion-hatches. The waterlock appliance employed in the original boat has now an additional use in supplying a mode of egress and ingress, the opening being made telescopic, so as to permit surface runs in comparatively rough water. When submerged, the smoke-stack acts telescopically, and is closed with a water-tight valve. To avoid the necessity of divers going out of the boat when under water, there are various openings at places in the exterior skin to which rubber sleeves or arms, with a radius sufficient to cover almost all practical necessities, will be fitted. These apertures do not constitute planes of weakness or danger, because they are normally closed by stout water-tight dead-lights.
THE SUBMARINE MONITOR “PEACEMAKER.”
The Westinghouse engine is employed, as its construction prevents, by the packing used, any radiation of heat and the consequent elevation of temperation below. The air-tight doors and bulkheads work laterally, and the conning-dome is made of steel, with such apertures as will enable the helmsman to have, when on the surface, an all-round view, and when submerged, a sufficient light to let him in the daytime read, at a depth of thirty feet, the time by his watch.
Should the necessity arise, when submerged, the purity of the atmosphere below is preserved by passing the air through caustic soda, thus eliminating carbonic acid gas, and by reinforcing the loss of oxygen from tanks of compressed air. In the original experiments the boat was frequently submerged six hours at a time, and the crew of two men had no other air supplied than that which the boat carried down with her.
Besides these chemical means there are rubber tubes floated by buoys, with nozzles which protrude above the wash of the surface water. There is in each tube an automatic valve, which prevents water coming through the pipe at the time the air is being pumped in, and the depth below the surface to which outside air can be supplied is limited only by the length of the pipe.