5. Iron bolts and screws.
6. How deep the ship goes into the water when awash.
7. The pivots on which the paddle-wheel turns.
8. Air holes.
9. Gallery along which men can move.
The inset is a drawing of the paddle-wheels which fill the centre portion of the boat and which work upon the pivot marked 7.
Vain would it be for ships lying in harbor to be regarded as safe, for the inventor could reach anywhere unless prevented by betrayal. None but he could control the craft. Therefore it may truly be called the lightning of the sea.
Its power shall be proven by a trip to the East Indies in six weeks or to France and back in a day, for as fast as a bird flieth can one travel in this boat.
This boat was 72 feet in length, and her greatest height was 12 feet, while the greatest breadth was 8 feet, tapering off to points at the end. Capt. Murray Sueter in his book on submarines gives these and other particulars of the vessel. At either end the boat had a cabin, the air in which remained good for about three hours, and in the middle of the boat was a large paddlewheel rotated by clockwork mechanism, which, it was claimed, would run for eight hours when once wound up. The iron tips at the ends of the vessel were intended for ramming, and the inventor was confident he could sink the biggest English ship afloat by crushing in her hull under water. The boat was duly launched, but on trial of the machinery being made the paddlewheel, though it revolved in air, would not move in the water, the machinery being not powerful enough. This, says Capt. Sueter, was apparently the only reason for de Son's failure, for his principles were distinctly sound, and he was certainly the first inventor of the mechanically propelled semi-submarine boat. After her failure de Son exhibited her for a trifle to any casual passer-by.