varied from sixty to one hundred pounds rifle powder, though other explosives might have been more advantageously used if they had been available to us. Generally four of the fuses were attached to the head of each torpedo so as to secure the discharge at any angle of attack. These firing tubes or fuses were afterward modified to avoid the great risk consequent upon screwing them in place and of having them permanently attached to the charged torpedo. The shell of the latter was thinned at the point where the tube was attached, so that, under water pressure, the explosion of the tube would certainly break it and discharge the torpedo; though, when unsubmerged, the explosion of the tube would vent itself in the open air without breaking the shell. In this arrangement the tube was of brass, with a leaden head, and made water-tight by means of a screw plug at its base. Both the shell and the tube being made independently water-tight, the screw connection between the two was made loose, so that the tube could be attached or detached readily with the fingers. The mode adopted for testing against leakage was by placing them in a vessel of alcohol, under the glass exhaust of an air-pump. When no air bubbles appeared the tubes could be relied on. Captain Lee had also an electric torpedo which exploded by concussion against a hard object; the electric current being thus established, insured the discharge at the right moment.
Captain Lee is the inventor also of the "spar-torpedo" as an attachn1ent to vessels, now in general use in the Federal navy. It originated as follows: He reported to me that he thought he could blow up successfully any vessel by means of a torpedo carried some five or six feet under water at the end of a pole ten or twelve feet long, which should be attached to the bow of a skiff or rowboat. I authorized an experiment upon the hulk of an unfinished and condemned gunboat anchored in the harbor, and loaded for the purpose with all kinds of rubbish taken from the "burnt district" of the city. It was a complete success; a large hole was made in the side of the hulk, the rubbish being blown high in the air, and the vessel sank in less than a minute.[1] I then determined
- ↑ Since writing the above I have been informed by Captain F. Barrett, United States Navy, that he had invented the same "spar-torpedo" in the first year of the war, but it had not been applied by the Federals. In the spring of 1862, I had also recommended its use to General Lovell for the defence of New Orleans, by arming river boats with it to make night attacks on the enemy's fleet—but it was proposed to use it above water.
