Of Fulton’s early experiments and failures in the matter of submarines and torpedoes it is unnecessary to speak. In 1814, some years after his return to the United States from Europe, where he had been impartially offering his services to the French and then the British, he submitted to the American coast and harbour defence committee plans for a steam warship which was to carry a large number of guns.
The boat was launched in October of that year and given the pedantic name of Demologos, which was simplified to Fulton the First. The war ended before the vessel could be tested, and she became a receiving ship. Her machinery was arranged to drive a large paddle-wheel, placed amidships and working in a tunnel in the hull. She was to carry twenty guns, not forty-four as sometimes stated, and furnaces for red-hot shot, and was to travel at a rate of four miles an hour. Besides her deck armament it was proposed that she should have two submarine guns suspended from each bow, which were to send a hundred-pound ball into an enemy’s hull ten or twelve feet below the water-line. Her machinery was intended to pump a tremendous column of water upon the enemy’s decks and through the latter’s portholes. Her gun-deck was completely covered over so that no hostile shot could reach it from above. Her wooden walls were five feet in thickness, and capable of withstanding the heaviest shot of the day. The dimensions of this remarkable craft were: length, 156 feet; beam, 56 feet; and depth, 20 feet; but her draught, loaded, was only 10 feet. The water-wheel, the position of which is indicated in the centre of the accompanying plan of the gun-deck, was 16 feet in diameter, and had blades or buckets measuring 14 feet with a dip of 4 feet. The cylinder of the engine measured 48 inches, and the stroke was of 5 feet. The boiler was 22 feet long by 12 feet beam, and 8 feet deep. The gross tonnage of the vessel is set down at 2,475 tons. The ship was two-masted, and could steam either end foremost. She was built at Brown’s yard at New York, in four months after her keel was laid, and given her machinery and guns at Fulton’s works on the North River.
Another vessel, destined like the Demologos never to see active service, but which, nevertheless, was the first iron-clad steamer actually built, was the ship designed, in 1841, by Edwin A. Stevens, a son of John Stevens, at the time that hostilities were feared between England and the United States.
Mr. J. Elfreth Watkins, in an address before the Philosophical Society of Washington, in 1892, said:—“As thick armour plate could not be made at that date, he devised the method of armour plating in laminæ, or plates laid over each other and riveted. He then made a series of experiments to determine the thickness of plating required to resist the different sizes of balls then in use. From these experiments, which were made at Bordentown, N.J., in the summer of 1841, he made the deduction that a target of iron 4½ inches thick would resist a 64 lb. shot, at that time the heaviest ball used in our navy.”
This standard of thickness was afterwards adopted by European naval architects for warship iron armour.
A committee of naval and military officers was appointed which made numerous tests, and as a result Congress entered into a contract with Stevens for the construction of “a war steamer, shot and shell proof, to be built principally of iron,” and making an appropriation for the purpose.
Up to this time there had been but little change in the power of guns since the time of Nelson, but Commodore R. F. Stockton’s successful construction in England of a wrought-iron gun throwing a round shot able to pierce a target 4½ inches thick, induced Robert Stevens, who was associated with Edwin A. Stevens, to alter the plans and increase the thickness of the armour so as to fulfil his contract to build a ship that should be “shot and shell proof.”
The production of still more powerful guns, both in America and Europe, caused more alterations and delay. It is of interest to note the dimensions of this vessel in order to see to what an extent Stevens anticipated the designs of some later engineers. When Robert Stevens died, in 1856, the ship was then 410 feet long, 45 feet inside the armour shell, with two feet of freeboard, and with a square, immovable turret enclosing depressible guns. She had her engines and boilers, and it would not have taken long to complete her; but for some reason, which need not be gone into here, except that the vessel was too far in advance of the officials at Washington, who were wedded to wood and sail, she was never launched, and was ultimately sold in 1881 for old material. Besides being armoured and turreted, she had a powerful ram of the “axe-head” pattern.
THE STEVENS BATTERY.