"Pick twelve men of the crew and have them ready to go aboard the U-16 with Captain Bernstorff here," he commanded.

The officer saluted and withdrew.

"Now, is there anything further I can do for you?" asked Von Rosten.

"Nothing, thank you," replied Lord Hastings, "and, with your permission, as soon as Davis is freed of his shackles and the men are ready, I shall return to my own vessel. I have work to do."

The young German bowed.

Half an hour later Lord Hastings, Jack and Frank again trod the deck of the U-16. Davis and a crew of twelve German sailors also were aboard.

"And now," said Lord Hastings, "having dispensed with the formalities, it is time to get busy."

CHAPTER XV.

PLOTTING.

"Now," said Lord Hastings, "as soon as we have lost sight of our new friend, Von Rosten, we shall take a little trip to Ostend anyhow."

"What for, sir?" asked Frank.

"Oh, just to look about a little," was the reply. "We may be able to pick up a little useful information."

"And why didn't you tell Von Rosten you were bound there, sir?" Jack wanted to know.

"Well, for one reason, because I wanted to borrow a part of his crew,"

said Lord Hastings. "Had he known we were headed for Ostend he would have thought it strange that we didn't wait until we got there to get more men. Besides, I wouldn't want to try and get men there. It might prove embarra.s.sing."

"Well, sir," remarked Frank, "that was quite a little story you concocted for his benefit."

"I flatter myself it wasn't so awfully bad," smiled Lord Hastings. "Of course, I might have done better if I had been given more time."

"It was pretty good for a quick one," Jack admitted. "But, what are we going to do with Davis, sir?"

"Turn him over to the British authorities at the first opportunity. He is deserving of whatever punishment he shall receive. But in the meantime we must not let him suspect our true ident.i.ty for he may be of use to us."

The lads nodded.

"Now," said Lord Hastings, "we may as well put about and run for Ostend."

Frank gave the command to Edwards, at the wheel, and the U-16 came about and headed east. Frank and Jack went below to their quarters, leaving Lord Hastings alone on the bridge.

"There is no use talking," said the latter. "It seems rather peculiar to be sailing under the German flag."

"And that's no joke," Jack agreed. "I hope we will not have to do it long."

It was late in the evening when the submarine approached Ostend, where it was known that the Germans had established a submarine base. The U-16 went along slowly, for Lord Hastings was not certain of his bearings.

Suddenly there came a hail across the water and a light flashed upon the U-16. In response to a command Lord Hastings brought the vessel to a halt.

"Who are you?" came the challenge in the darkness.

"U-16, Captain Tarlenhein," Lord Hastings shouted back.

"Good," was the reply. "We wondered what had happened to you. Everything all right?"

"All right."

"Ready to join us in another desperate mission?"

"Yes. Ready any time."

"Good. Remain where you are. We start within the hour. Your instructions will be sent to you."

Lord Hastings signified that he understood and the light on the other vessel was flashed off, leaving the U-16 in darkness again.

"Now what do you suppose is up, sir?" asked Frank eagerly.

"You have just as much idea as I have," declared Lord Hastings.

"However, we shall probably know in good time."

And he was right.

Half an hour later a small boat approached the side of the U-16. In response to a signal from Lord Hastings, who had perceived his approach, a subordinate officer clambered aboard.

"Captain Tarlenhein?" he inquired.

Lord Hastings kept his face half turned in the darkness.

"Yes," he replied in a husky voice.

The officer drew a paper from his pocket and pa.s.sed it to Lord Hastings.

"From Admiral Seibert, sir."

He brought his heels together, gave a quick salute, turned on his heel, and went back over the side.

Lord Hastings immediately hastened to his cabin and as hastily summoned Jack and Frank.

"Well," he said quietly, "here are our orders," and he laid the paper on the table. "Sit down."

The lads did so, and Lord Hastings, seating himself, picked up the doc.u.ment, broke the seal, and read aloud:

"Captain Tarlenhein,