In this case, the torpedo is launched when on the quarter of the vessel attacked, as at A, the tow-rope left slack. After steaming ahead some distance, hold fast the tow-rope, when, by continuing to steam on, the torpedo will diverge into contact with the bottom of the vessel attacked, as shown in the drawing. _When skilfully performed_, the total destruction of the enemy is certain, since the torpedo is springing from a depth to the surface, and will, in consequence, strike near the keel. The torpedo vessel can pass at her greatest speed, and, if thought necessary, near enough to clear away any of the ordinary obstructions, such as booms, nets, &c. [Illustration: Plate 6. Kell Bros. Lith. London. CASE 3.—ATTACKING A VESSEL AT ANCHOR BY PASSING ON EITHER SIDE.] CASE 4. ATTACKING A VESSEL AT ANCHOR BY COMING UP RIGHT ASTERN AND THEN PASSING ON EITHER SIDE. In this case, having determined upon the side it is desirable to pass, a torpedo is launched accordingly. When near the vessel, the torpedo is sufficiently diverged, and the torpedo vessel passing onwards ahead, the torpedo is brought under the run or bottom of the vessel attacked, as shown by the drawing. [Illustration: Plate 7. Kell Bros. Lith. London. CASE 4.—ATTACKING A VESSEL AT ANCHOR COMING UP FROM ASTERN AND THEN PASSING ON EITHER SIDE.] CASE 5. PASSING DOWN BETWEEN TWO LINES OF VESSELS AT ANCHOR, AND DESTROYING THEM ON EITHER SIDE. In this case, it would be impossible to fire at the torpedo vessel for fear of injury to their friends. Two or more torpedo vessels following each other with preconcerted signals would cause great destruction. [Illustration: Plate 8. Kell Bros. Lith. London. CASE 5.—PASSING BETWEEN TWO VESSELS AT ANCHOR.] CASE 6. ATTACKING A VESSEL IN MOTION BY COMING DOWN FROM RIGHT AHEAD. In this case, two torpedoes are launched, port and starboard, each diverging to its full extent; when passing the vessel attacked, one or the other of the tow-ropes is brought across the cut-water, and by the simultaneous motion of the two vessels in opposite directions, the torpedo is brought alongside of or under the bottom of the vessel attacked, as shown by the drawing. The torpedo vessel should keep the masts of her enemy in one until close to, when either torpedo will be used, according to the movement of the enemy. At the time of the tow-rope taking the cut-water, the brake is suddenly eased up; the tow-rope will then pass under the bottom, when, by checking the tow-rope, the torpedo will be hauled under the bottom. [Illustration: Plate 9. Kell Bros. Lith. London. CASE 6.—ATTACKING A VESSEL IN MOTION COMING DOWN FROM AHEAD.] CASE 7. ATTACKING A VESSEL IN MOTION, COMING UP TO HER FROM RIGHT ASTERN.