There has been considerable advancement along these lines in naval architecture in France. Gustave Zédé has done much, and in 1886 built an experimental boat called the "Gymnote." This was constructed something like a large White-head torpedo. It was 56.7 feet long, 5.9 feet in diameter, made of sheet-steel, cigar-shaped, and had a displacement of 30 tons. Driven, when submerged, at a speed of 7 knots an hour by an electrical propeller, and 9 knots above water, this craft proved that much might be done in submarine navigation. Both upright and horizontal rudders were used so that the boat might be steered straight ahead, or made to dive or ascend at will. The batteries would run the device four or five hours constantly. The boat was sunk by means of a heavy ballast attached to the keel of the boat, which was so arranged that it could be detached at a moment's notice. Buoyancy was secured by water-tight compartments which also supplied compressed air for a crew of fire men, when submerged. A long tube ran from the top of the Gymnote, upwards, to the surface of the water. This was equipped with a lens and reflecting mirror. By bending these at right angles a picture of the whole horizon could be seen below. Thus was the boat directed when under water.
So successful were the experiments with this craft that the French government had Zédé work out another boat of greater dimensions. This was named after the inventor, was 147 feet long, 10.75 feet in diameter, had a displacement of 260 tons and, like its predecessor, was cigar-shaped. It could run with a crew of 10 men at the rate of 14 knots on the surface, and 8½ knots below. It was equipped to discharge torpedoes.
Other inventors have been at work on similar lines and some of the successful boats turned out have been the Peral, the Nordenfeldt, the Argonaut and the Holland. The last named has been used with some success in the United States Navy, and is the invention of John P. Holland. The idea of such a craft came to Holland when he was a teacher in Cork, Ireland, where he devoted his spare time to the study of navigation. As far back as 1862, he had made diagrams of a boat drafted on similar lines with the Holland. Holland taught school for six years after his arrival here, at Paterson, New Jersey, while he sought financial support to bring his plans before the government. In 1875, he submitted plans to the United States officials, which provided for the construction of a cigar-shaped boat, 15 feet long, that would accommodate one man in a sitting posture who should propel the boat by treadle power. Much adverse criticism was meted out to these plans, but the boat was built and tried successfully in the Passaic river, near Paterson. So marked was its success that Holland gave up school-teaching and went to perfecting his new craft. J. Breslin, of Paterson, was his supporter. In timeby 1895the Holland boat, much after the style of the best submarine devices of the present, was completed, and demonstrated its ability to sub-navigate the sea.
A number of these boats have been built for the United States government at a cost of $175,000 each.
One odd craft for sub-sea work is the "Argonaut," the invention of Simon Lake. It is constructed to float on the surface after the manner of a yacht, dive under water as a submarine navigator, and once under water, to avoid obstacles by being propelled, like an automobile, on wheels along the bed of the ocean or river. This craft is equipped with three wheels, one of which is at the stern and moves so as to steer the boat in it operations. This wheel is also the rudder when the boat is afloat. Only a little weight is necessary to keep the boat on the bottom. Like other vessels of its kind, it has adjustable ballast or weights on its keel. Water is let into the hold to start it downward, and when, it is desirable to rise, the weights may be cast off. This vessel is 36 feet long, cigar shaped, with a blunt nose and pointed stern, and is fitted out with a 30-horse-power engine, which is used to drive the screw propeller, driving wheels, the electric dynamo, air compressor and derricks for hoisting wrecks. A steel tube rises like a mast out of the water when the vessel is not entirely submerged, and through this, air is taken in. The ship is equipped with a compass which is found to work well if kept away from the machinery. When the boat is closed up entirely for deep diving, the engines must be stopped for want of air, and then storage batteries operate the machinery. The engines run by gasoline fuel. Air sufficient to supply five men for 24 hours can be carried, and the supply can be increased by running up near the surface and taking in air through the mast tube. This craft is also equipped with a device for leaving the boat when it is under water. A compressed air compartment, with an air lock, is arranged so that by having a strong air pressure in this room, a hole in the bottom of the boat may be opened, and the air pressure being greater than that of the water when it presses to get in, divers can leave the boat and enter again without danger. This manhole is intended for use in leaving the boat to explore wrecks, or in time of war, to pick up and cut cables, and for similar uses. This boat has made successful trips of over 1,000 miles under water.
The torpedo boats built by the United States Government are capable of steaming a maximum speed of 26 knots. The prin- cipal dimensions are, length, 170 feet; beam, 17 feet; draught, 5 feet 4 inches; and displacement, 180 tons. The engines are triple expansion and twin-screw, and capable of developing 3,200 indicated horse-power, when making 395 revolutions per minute.
The armament of these boats consists of three torpedo tubes, four 1-pounder, quick-firing guns, four 18-inch Whitehead torpedoes, and 600 rounds of 1-pounder ammunition. In speed, tonnage and armament, these craft almost rankwith torpedo-boat destroyers.
1Submarine boat "Holland" in action. Possible results shown by practice maneuvers in Narragansett Bay, when the submarine vessel approached close enough to the big cruiser "New York" to blow her out of the water. This was done under the penetrating glare of the fleet's searchlights, which failed to discover the "Holland" until the latter rose to the surface within 75 yards of the supposed enemy.
This vessel proved so successful that six more are nearly completed for the US Government and England has five in commission.
The "Holland" is 54 feet long and 10½ feet wide. She contains a 50-horse power gasoline engine for propulsion; five torpedoes for attack and requires but nine tons of water ballast to submerge her in three minutes. Her speed is ten knots on the surface, and eight when running under water.