5.--_Cable Cutters._--Cable cutters, that is submarine guns discharging a sharp piece of iron in the shape of a crescent, with sufficient force to cut through ship's cables, or other obstructions.[E] _Practical Experiments._--Various and exhaustive experiments were carried out in the presence of the Commissioners, tending generally to impress them with a favourable view of Fulton's many projects. As a final test, the sloop _Argus_ was ordered, under the superintendence of Commodore Rodgers, to whom Fulton had previously explained his mode of attack, to be prepared to repel all attempts made against her by Fulton, with his torpedoes. _Defence of the "Argus."_--Though repeated attempts were made, none were successful, owing to the energetic, though somewhat exaggerated manner in which the defence of the sloop had been carried out. She was surrounded by numerous spars lashed together, nets down to the ground, grappling irons, heavy pieces of metal suspended from the yard arms ready to be dropped into any boat that came beneath them, scythes fitted to long spars for the purpose of mowing off the heads of any who might be rash enough to get within range of them. As Robert Fulton very justly remarked, "a system, then only in its infancy, which compelled a hostile vessel to guard herself by such extraordinary means could not fail of becoming a most important mode of warfare." Three of the Commissioners reported as favourably as could be expected, considering its infancy, on the practical value of Fulton's scheme of torpedo warfare. _Congress refuse aid._--But on the strength of Commodore Rodgers's report, which was as unfair and prejudiced, as the others were fair and unprejudiced, Congress refused Fulton any further aid, or to countenance any further experiments that he might still feel inclined to prosecute. Though undeterred by this fresh instance of neglect, and still having a firm belief in the efficacy of his various torpedo projects, yet other important matters connected with the improvement of the steam engine occupied his whole time and prevented him from making any further experiments with his submarine inventions. _Mode of Firing, 1829._--Up to 1829, that is to say for nearly sixty years after the invention of torpedoes, mechanical means only were employed to effect the ignition of the torpedo charges, such as levers, clockwork, and triggers pulled by hand; with such crude means of exploding them, it is not extraordinary to find, that all the attempts made to destroy hostile ships, resulted in failure. [Illustration: FULTON'S TORPEDOES. PLATE I]