each will lock its lever H so that it cannot strike fire, and the Torpedo may be handled with perfect safety. Not having time to engrave this improvement, it shall be exhibited to Congress in a working model, by which it will also be better understood. I will now suppose the enemy to be approaching a port; a signal announces them; our boats run out and throw into the channel two hundred Torpedoes, set each to 15 days. Should the enemy sail among them, the consequence will teach future caution; should they cruise or anchor at a distance, what could they do? They not knowing the number of Torpedoes which were put down, nor the day on which they were to rise to the surface, could not have their boats out exposed to our fire, and waiting from day to day for a time uncertain. Whereas, our officers, knowing the number which were put down, and the day they were to rise to the surface, would have their boats ready to take them in, and at the same time replace them with others set for ten, fifteen, twenty, or more days. Viewing this subject in all its bearings, the impression on my mind is, that it would be impossible for an enemy to enter a port where anchored Torpedoes were thus used, without their incurring danger of such a kind, that courage could not guard them from its consequences. Prudence and justice would warrant their abandoning such an enterprise; and the probability is, that knowing us to be thus prepared, they never would attempt it, or should they, and only one vessel were to be destroyed, we might calculate on its good effect to protect us from future hostile enterprises. [Illustration: PLATE III.] PLATE III _Represents a clockwork Torpedo, as prepared for the attack of a vessel while at anchor or under sail, by harpooning her in the larboard and starboard bow._