"I shall go up the stairway, followed by Alfred. While this is going on it will be your duty, Ralph, to watch the workers at the dynamo and the aft tank. They are the only ones who will be able to see the stairway clearly. If you see any look of alarm on their faces, or see that they notice what is going on, move around into the opening, and level both revolvers at them, without, however, making any sound. Hold them in that position until I raise the trap-door and warn the sub-lieutenant. Alfred will follow close and hold the trap-door from being sprung. Then move up the companionway as fast as you can. There, he is going up now. Take your place, Ralph." The crucial time had come. Alfred retreated into the little room as the captain leisurely moved along the narrow passageway toward the dynamos. Thus they waited and waited, five, ten minutes. Ages seemed to pass. Then the hatch door opened slowly. Alfred came out quietly without looking around, moved forward, and then walked back and slid into the corner of the room. The petty officer closed the hatch and moved down the steps, brushing past the captain. As he did so the captain entered the door and immediately turned with the revolver pointing at the officer's breast. "Not a sound, or I fire," said the captain in a voice which could not be heard a dozen feet away. The captain stepped aside, and pointed to the open doorway, at the same time indicating by motions that the German should enter it. The officer gritted his teeth and finally obeyed. As the captain stood there with the revolver at his side, but pointed at the man, Alfred slowly closed the door. The captain now turned and moved up the stairway. With his revolver drawn he pushed open the trap-door quietly, and, in a quiet voice, said: "Hands up!" The sub-lieutenant turned quickly, to look into the muzzle of the revolver. His hands reached out to seize a lever. "_Stop!_" said the captain, and the officer quickly raised his hands. Alfred was now in the tower, and Ralph, walking up backwards, had his head through the hatch opening, when a shot was fired. He dropped one of his revolvers, and Alfred quickly seized him by the shoulders and drew him up. The hatch cover came down with a bang. "Are you hurt?" asked Alfred, as Ralph dropped down, but he was reassured as the latter arose. For the moment the captain's gaze was averted, when, quick as thought, the officer's hand touched a lever. The captain smiled, as he said: "I am afraid the valve of the submerging tank will not work; I prefer running on the surface. But, in the meantime, as I am commander of this vessel, and I notice that you are trying to interfere, I shall have to restrict your movements somewhat." Saying this he drew a small cord from his pocket and instructed Alfred to bind the arms at the wrists. The hands of the officer were then carried around to the back and the cord fastened to a stanchion at one side, where he was out of reach of the instrument board.