Robert Fulton and the Submarine

by William Barclay Parsons

Fulton begins work on a submarine (1797). Nautilus launched at Rouen (1800). Havre experiments. Fulton aided by Monge and Laplace. Received in audience by Napoleon Bonaparte. Hopes and disappointments.

The previous chapter shows that not only was the principle of a submarine boat not novel when Fulton began his work on it, but that according to the record a competitor was actually in France urging upon the French Government the adoption of a design that, unlike the fantastic conceptions of Bourne and Drebbel, was capable of being moved by an invisible power and of making an attack beneath the surface. But if Fulton lacked initial originality he achieved practical success in his subsequent labors by greatly improving the plans of his predecessors, as he later did in the case of the steamboat.

At first his work on a design for a submarine was merely incidental and secondary to his more cherished ambition to become a great constructor of canals. It was soon after his arrival in France that the idea of an underwater boat occurred to him, and this several years before mechanical operation of boats obtained the supremacy in his mind over small canals. His first move was apparently on the 24 Frimaire an VI (13 December, 1797) when he wrote to the Directory, “having in view the great importance of lessening the power of the English fleet, that he had a project for the construction of a mechanical Nautilus.” It is interesting to note that this letter was written but six months after his arrival in France, and in the same year that Delpeuch records Bushnell as having laid his own plan before the Directory. It is difficult to repress the thought that the latter’s efforts roused Fulton to action, even if they did not suggest to him the initial thought.

On the 2nd January, 1798, Fulton made definite proposals to the Minister of Marine, among the terms being a request that rank in the French navy be conferred at least on him, if not on all the members of the crews of the submarines, because otherwise he feared the British would treat him as a pirate. On February 12, 1798, Fulton was informed that his proposals had been declined.

Unlike Bushnell, who under similar circumstances went home discouraged and hid himself under an assumed name, Fulton prepared to renew the attack. Waiting until another Minister of Marine had been appointed, he submitted new proposals, under date of 5 Thermidor an VI (23 July 1798), concluding the offer by pointing out that the destruction of the English navy would assure the freedom of the seas and the nation which had the most natural resources—France—would alone hold, and without rival, the balance of power in Europe. The Minister convened a board of technical men to whom Fulton submitted his plans for a submarine that he called the “Nautilus.” This boat had the shape of an imperfect ellipsoid, with an over-all length of 6 m. 48 (21 ft. 3 in.) and extreme beam 1 m. 94 (6 ft. 4 in.). Beneath the ellipsoid there was a hollow iron keel 0 m. 52 (1 ft. 8 in.) in height, running to within 1 m. from the bow. The keel contained a quantity of ballast so that the difference between the weight of the flotation and that of the water displaced by it should be only about 4 to 5 kilograms. The only communication with the interior of the keel lay in the two parts of a suction and force pump which by means of a hand crank would permit the introduction into or removal of water from the metal keel at will. The excess in buoyancy of the Nautilus being small, the introduction of only a little water would make it sink, and conversely, the expulsion of a small quantity would cause it to return to the surface. On the forward and top part of the Nautilus there was a spherical dome pierced with port holes covered by thick glass for observation and a man-hole that served as means of ingress and egress for the crew.

For propulsion, Fulton proposed a screw as Bushnell had already done, a principle that was not to be adopted in general practice until nearly half a century later in spite of its many and great advantages over side wheels. The screw was placed at the stern and directly ahead of the rudder and was operated by a hand crank and gearing turning a shaft passing through a stuffing box. The crank was to be turned by man power only. Plunging was to be secured by pumping water into the keel, while submersion at a given depth, provided the boat was in motion, was to be attempted by means of two inclined planes attached to the sides of the steering rudder. The angle of these planes could be altered from within, thus giving an upward or downward direction to the boat. Motion on the surface he thought to obtain by a fan-shaped sail which, with the supporting mast, could be folded down to the deck and then, preparatory to submersion, covered with envelopes like the wings of a fly. Fulton estimated that he could work the boat with a crew of three men.

FULTON’S “NAUTILUS,” 1798

The offensive feature of the design consisted first of a vertical spike attached to the top of the observer’s dome. In the spike was an eye through which passed a cord leading through a stuffing box to a winding spool in the forward end of the boat. The second part was a torpedo attached to the other end of the cord. In action the Nautilus would be placed directly beneath the hull of an enemy vessel, the spike being in contact with the bottom planking. As one end of the spike projected into the observer’s dome, a blow on that end would drive the upper end, which was sharp and detachable, into the ship’s timbers. Then the Nautilus was to move forward leaving the spike sticking in the ship. As she moved forward, the torpedo would trail behind, but as the cord passed through the eye in the spike, the torpedo would soon be brought into contact with the hull, when the shock would fire the discharge. In the meanwhile, enough cord would have been paid out to permit the Nautilus to have attained a safe distance.

The Commission to whom the design was submitted found in its favor, except as to the sail arrangement, which they pointed out had the larger part of its area too far aloft, and that consequently the boat would lack stability under a strong wind. A translation of the Commission’s conclusion is as follows: