On the first of October, 1805, captain Siccombe, in a galley with eight men and his coxswain, placed two Torpedoes in the manner described, Plate IV, Fig. 2, between the buoy and cable of a French gun-brig, in Boulogne roads. The tide drove them until they both lay perpendicular to her sides. When the French saw captain Siccombe advancing without answering the countersign, they exclaimed that the infernal machines were coming, and fired a volley of musketry at his boat, but without touching a man.[C] The moment the French fired, fearing the effect of the explosions, they all ran aft and were in the greatest confusion. The tide drove captain Siccombe's boat so far down, that he was obliged to cross under the brig's stern, where, seeing her men collected, and expecting another volley, he discharged at them two blunderbusses, each containing fifteen half-ounce balls[D], and was rowing away, when both Torpedoes exploded, but, to his astonishment, the brig was not destroyed. On the same night, lieutenant Payne, of captain Owen's ship _l'Immortality_, placed two Torpedoes across the bow of another French gun-brig; he received their fire, had one man wounded, rowed to some distance, and waited till he saw the explosion of the Torpedoes, which did not appear to do any injury to the vessel. When captain Siccombe called on me in the morning and reported these circumstances, I was much at a loss to account for the brig not being blown up. Defective in the experience which this failure gave me, I had not reflected, that if the copper case, with the clockwork and powder, weighed specifically fifteen or twenty pounds more than water, it would hang like a heavy pendulum to its suspending cork-box C, and if the coupling line were fixed in the centre of the end, as at A, Fig. 1, the action of the tide being equal on both sides, would have no tendency to sheer or drive it from its perpendicular position. After about half an hour's consideration, I was forcibly impressed with this error in arrangement, as the real cause of captain Siccombe's and lieutenant Payne's failure. [Footnote C: They had got some idea of these machines, from an attempt which had been made with them against the Boulogne flotilla, in Oct. 1804, called the Catamaran expedition.] [Footnote D: The report on this attack in the French papers, acknowledged that the brig had five men killed and eight wounded: this from two blunderbusses shews that the persons in the vessel attacked have to fear the small arms of the Torpedo boats.]