It was true. The submarines were approaching each other rapidly.

The enemy slowed down, and in response to Lord Hastings, the captured vessel did likewise. A voice from a figure on the bridge of the second vessel came across the water.

"Who are you?"

"U-16," answered Lord Hastings, who had gone through the former commander's papers carefully, "Bernstorff, commanding."

"Bernstorff," came the surprised response. "Where is Captain Tarlenhein?"

"If you will come aboard, I will explain," shouted Lord Hastings.

"Very well."

A few moments later a small boat left the side of the other vessel and came toward the U-16.

"Now, boys," said Lord Hastings quietly, "keep a tight rein on yourselves and leave the talking to me. Say nothing unless you are addressed. It would not do for us to be tripped up. We would all be put to death as spies."

The boys nodded their understanding of this order.

"We'll be as mum as a couple of oysters, sir," declared Frank.

"I wouldn't know what to say, anyhow," agreed Jack.

"Sh-h-h," whispered Lord Hastings. "Here he comes."

The small boat sc.r.a.ped the side of the U-16 at this juncture. A man in the full uniform of a German lieutenant commander stepped aboard. Lord Hastings advanced to meet him with extended hand.

Jack and Frank followed their commander closely.

CHAPTER XIV.

WITH THE ENEMY.

"I am Captain Bernstorff," said Lord Hastings quietly, "and you?"

"Lieutenant Commander Von Rosten, sir," replied the other, who could not have been more than twenty-five years of age.

"Von Rosten, to be sure," replied Lord Hastings, affecting to recall the name. "Allow me to present my friends, who are at present acting as my officers."

He beckoned to Frank and Jack to approach.

"Lieutenant Papen," he said, introducing Jack; "and Lieutenant Bohring,"

indicating Frank.

The three acknowledged the introductions and then Lord Hastings continued:

"I suppose you are wondering how I come to be in command of the U-16?"

"I am, sir," was the reply.

"And also," continued Lord Hastings with a smile, "you are no doubt wondering just who I am anyway?"

"I must confess to that, too," answered the young German.

"Well, I can explain in a very few words," said Lord Hastings quietly.

"In the first place, I carry a number--you know what I mean?"

The German nodded.

"The secret service," he said quietly.

Lord Hastings gave him a glance of approval and the young man flushed.

"Exactly," replied Lord Hastings. "My friends here also carry numbers.

They are young, as you see, but they have proved themselves more than once in His Majesty's service."

The young German bowed again.

"Now," continued Lord Hastings, "I shall take up the little matter of how I happen to be in command of the U-16 and the unfortunate fate of Captain Tarlenhein."

"Fate!" exclaimed Von Rosten.

"It is only too true," muttered Lord Hastings sorrowfully. "But he died as a loyal servant of the Emperor. I shall explain."

"If you will," said the young German.

"Under command of Captain Tarlenhein," said Lord Hastings, "the U-16, as you may possibly know, has been in the Irish Sea, and, at one time or another, off the mouth of the Thames. Whether you knew it or not, Captain Tarlenhein also carried a number. There was work to be done in England.

"Of course, we already had our agents there--in fact, I was one of them, and my two friends here. We were instructed to report to Captain Tarlenhein aboard the U-16 at a certain time. We did so, the vessel at that time lying off the Thames. Captain Tarlenhein had other instructions for us. We went ash.o.r.e again and there encountered trouble.

We were captured.

"In London we were being taken to The Tower, when we all made a break for liberty right in the middle of the city. Captain Tarlenhein was shot down. The rest of us escaped. Through the instrumentality of my peculiar resemblance to a British naval officer, we overcame numerous difficulties, although my young friends here almost came to grief. It was here that my striking resemblance to this British officer of whom I speak enabled them to get away. We were, of course, dressed in British uniforms, but the haste of another agent of the Emperor almost caused our undoing."

The German officer had followed this account with interest. Apparently he was much wrapped up in the narrative. He clenched his hand as Lord Hastings paused.

"And who was this agent?" he demanded.

"An Englishman," replied Lord Hastings slowly. "An Englishman known as Davis. He almost spoiled it all. However, we at length managed to escape in spite of Davis--I don't know what has become of him--and made our way, after many perils, to where the U-16 still awaited the return of its commander.

"And what was our surprise, when we went aboard, to find it occupied by two British officers and several British sailors. Fortunately for us, these British officers--lazy dogs--were sleeping at their posts and we pounced upon them and tumbled them overboard, all but three; whom we kept as a crew, our own men having been taken prisoners by the enemy.

That was only yesterday, and here we are."

Lord Hastings paused.

"You have indeed had a hard time," said the young German. "But I am glad to know you, all three of you. About this man Davis. I have a man aboard my ship who might possibly be the same. He says his name is Davis, and he is an Englishman; but I have placed no faith in his story. He is a shifty-eyed scoundrel. I picked him up off the British coast about two weeks ago."