"Unless," interrupted the captain.
The officer nodded his head. "I supposed so!" continued the captain. "The lieutenant in the galley has the key which controls the automatic device. You may open the door and get the key, and from this time forward, if I find that you deceive me in the slightest degree, or make any attempt to injure the vessel, I will make it your grave without a moment's hesitation, and without the least compunction."
The sub-lieutenant moved toward the galley, and opened the door. In a moment he reappeared with the key and followed the captain to the conning tower.
Below the switchboard was a tiny slot. Into this the key neatly fitted, and upon giving a turn, a set of switches was exposed.
"These are the control circuits," he said.
"Turn them off and open the boxes below!" ordered the captain. This was done.
"Who are the men that operate the trimming tanks?" asked the captain.
"The machinist Scholer and his assistant Bracher," was the reply.
"Lieutenant," said the captain, addressing the commander of the chaser; "send those men on board."
When they appeared the captain continued: "You will go below with these men, and obey my signals, as we take the vessel to port, and remember, that if any part of the machinery is destroyed I will not guarantee to deliver you safely on shore."