England, at that time, being mistress of the seas, it was clearly her interest to make the world believe that Fulton's schemes were impracticable and absurd. Earl St. Vincent, in a conversation with Fulton, told him in very strong language, "that Pitt was a fool for encouraging a mode of warfare, which, if successful, would wrest the trident from those who then claimed to bear it, as the sceptre of supremacy on the ocean."[C] Wearied with incessant applications and neglect, and with failures, not with his inventions, but in inducing governments to accept them, he left England in 1806, and returned to his native country. _Application to Congress for Help._--Arrived there, he lost no time in solicitating aid from Congress to enable him to carry out experiments with his torpedoes and submarine boats, practice alone in his opinion being necessary to develop the extraordinary powers of his invention, as an auxiliary to harbour defence. By incessant applications to his government, and by circulating his torpedo book[D] among the members, in which he had given detailed accounts of all his previous experiments in France and England, and elaborate plans for rendering American harbours, etc., invulnerable to British attack, a Commission was appointed to inquire into and practically test the value of these schemes. They were as follows:-- 1.--_Drifting Torpedoes._--Two torpedoes connected by a line floated in the tide at a certain depth, and suffered to drift across the bows of the vessel to be attacked; the coupling line being arrested by the ship's cable would cause the torpedoes to be forced under her bottom; this plan is represented and will be readily understood by Fig. 3. 2.--_Harpoon Torpedo._--A torpedo attached to one end of a line, the other part to a harpoon, which was to be fired into the bows of the doomed vessel from a piece of ordnance mounted in the bows of a boat, specially constructed for the purpose; the line being fixed to the vessel by the harpoon, the current, if the vessel were at anchor, or her progress if underweigh, would carry the torpedo under her bottom. Fig. 2 represents this type of Fulton's submarine infernal machine. 3.--_Spar Torpedo._--A torpedo attached to a spar suspended by a swivel from the bowsprit of a torpedo boat, so nearly balanced, that a man could easily depress, or elevate the torpedo with one hand, whilst with the other he pulled a trigger and exploded it. 4.--_Block Ship._--Block ships, that is vessels from 50 to 100 tons, constructed with sides impervious to cannon shot, and decks made impenetrable to musket shot. A spar torpedo _a, a, a_, to be carried on each bow and quarter Fig. 4 represents this curious craft. _Stationary Mines._--Stationary buoyant torpedoes for harbour defence, to be fired by means of levers attached to triggers. This kind of mine is shown at Fig. 1.