a powerful screw which the inventor intended to drive into the hold of the opposing warship, and then make the best of his way to safety, leaving the magazine attached to the screw. He was more anxious to find someone to make the attack on the British ships than to do it himself. [Illustration: THE “HOLLAND” SUBMARINE.] [Illustration: THE “GOUBET” SUBMARINE.] Probably the first really successfully designed submarine was that of Robert Fulton, the American, who submitted his plans of the _Nautilus_ to the French Directory in 1797. His first boat was tried experimentally on the Seine in 1800. His next boat had iron ribs, and was copper-sheathed, and was shaped like a very long egg; it was fitted with a small hinged mast and a bat-wing sail, so that it could be used for surface navigation if necessary. He made a few descents in the Seine with success, but at no time stayed under water more than twenty minutes. Still, the experiment was held to be sufficiently promising for the boat to be tried at Brest, where he failed in his attempts to do any damage to the English ships of war. A preliminary experiment, before that against the English, was successful. On the British side, a so-called catamaran was contrived, by which it was intended to blow up the French ships at Boulogne. The catamaran consisted of a framework in which one man should sit immersed up to his arm-pits, and should paddle himself along under cover of darkness, and tow a floating box of powder to be exploded by clockwork in so many minutes, this affording him time to paddle away in safety. This floating mine or torpedo was to be fastened under the counter of the wooden man-of-war. Fulton is supposed to have had a hand in this, but the attack when it was made ended in an absolute failure, the catamarans making the attack being mostly blown up, while those vessels against which it was directed suffered no harm whatever. Upon his return to America, Fulton constructed a submersible called the _Mute_, which was to fire “Colombiads,” or under-water guns. Her inventor died during the course of her trials, which, however, did not reveal anything to show that the boat would have been other than an absolute failure as a warship. Though the British and the French naval authorities were strongly opposed to submarine warfare for a variety of reasons, American inventors continued their experiments. A diving boat passed under the British 74-gun ship _Ramilies_ three times, and at last got close under the vessel, and tried to fasten a clockwork mine to it by means of a screw after the plan Bushnell adopted, but the screw broke. Other attempts were made, and as there were then no means of discovering when a submarine attack was intended, the British officer in command placed a number of American prisoners on board his ships and notified the American Government that if any of the ships were blown up, the American prisoners as well as the crew would go with it.