“A good idea,” said Jack, “if we could only get him.”

“We shall make a try at it,” said his commander.

“How?” asked Jack.

For answer Lord Hastings turned and went below, and in another moment the D-16 began creeping toward the German submarine.

At a distance of only a few yards she stopped and Lord Hastings motioned to Jack to follow him, as he dropped over the side into the little launch which had been lowered into the water. To Frank he called:

“If we do not reappear on deck within ten minutes, sink her.”

Frank indicated that he understood, and Lord Hastings and Jack put off for the enemy.

They clambered quietly aboard, and descended below without so much as being challenged. Just at the bottom of the companionway they came upon the figure of a man who emerged from one of the compartments. At sight of the British uniforms the man staggered back and his hand went to his side, but before he could draw a weapon, Jack had him covered with his own automatic and spoke quietly.

“One move and you are a dead man,” he said quietly.

“Who are you?” asked the man in a low voice.