"You don't expect them to tip the Washington government off in advance, do you?" asked Frank with a laugh.

"Hardly; but it would seem that if such a campaign had been planned it would have been started before this."

"It wouldn't surprise me," said Frank, "to get a flash any day that a ship had been submarined off the American coast."

Came a rap at the door.

"Come in," Frank called.

A bell boy entered. He held a tray in his hand and on the tray was a cablegram.

"From Lord Hastings, I suppose," said Frank, taking the message and passing it to Jack.

Jack broke the seal, spread out the paper. The message, in code, was this:

"Authentic information flotilla submarines headed for America.

Warn Navy Department at once."

Jack sprang to the telephone and got the British embassy on the wire.

"The ambassador, quick!" he said to the voice that answered his call.

There was a short pause, and then Jack recognized the ambassador's voice.

"I've just had a wireless from Lord Hastings relative to the matter which we discussed with Secretary Daniels several weeks ago," he explained. "Can you arrange another interview immediately?"

"I'll see," said the ambassador and rang off.

The telephone in the lads' room jangled sharply ten minutes later. Jack sprang to the wire.

"Yes," he said in response to a query. "Ten o'clock? You'll call for us?

Very well."

He replaced the receiver and turned to Frank.

"We will see Secretary Daniels in his office at ten," he said. He looked at his watch. "Hurry and dress. It's after nine now. The ambassador should be here in fifteen minutes."

The lads jumped into their clothes, then went downstairs, where they awaited the arrival of the ambassador. The latter arrived ten minutes before ten o'clock, and the three were driven to the War and Navy building. Secretary Daniels received them at once.

"I understand that you come on a very important matter," he said. "Pray, what is it, gentlemen?"

For answer Jack laid before the American naval secretary the decoded message from Lord Hastings. The secretary read it, then looked up.

"Well?" he asked.

"Why, sir," said Jack, "Lord Hastings simply wishes you to take all precautions to prevent sinking of vessels by submarines in American waters."

Secretary Daniels smiled.

"I don't know what we can do that has not already been done," he replied.

"The off-coast waters are mined, and American warships are patroling the regular channels of navigation."

"All that may be true, sir," said Jack, "but these submarines are slippery customers, as I have reason to know. It would be well to take even further precautions."

"And what would you suggest?" asked Secretary Daniels.

"Why, sir," said Jack, "I'd suggest cancelling sailing orders of all transports temporarily, at least until such time as I felt sure they could go in safety. Then I'd flash a warning broadcast to all vessels within reach of the wireless to be on the lookout for enemy submarines. I'd rush every available submarine chaser in the Atlantic ports beyond the mine fields and I would order a destroyer as protection for every vessel known to be inward bound."

Secretary Daniels smiled.

"You wouldn't overlook anything, would you, Captain?"

"I certainly would not," said Jack firmly.

"Very well, then," said Secretary Daniels. "I'll set your mind at rest.

Your suggestions shall be followed out. I'll give the necessary directions the first thing in the morning."

"In the morning, sir?" repeated Jack. "The morning may be too late."

"Oh, I guess not," Secretary Daniels smiled. "It has been three weeks or more since your first warning and nothing has happened. I guess we can safely depend upon being let alone a few hours after the second warning."

Jack was about to protest, thought better of it and said simply:

"Very well, sir."

A moment later the lads took their departure with the ambassador. In the seclusion of the latter's automobile, Jack said:

"I can't see how the secretary dares let time slip by like that."

"Never mind," said the ambassador, "you'll find in a day or two that Secretary Daniels knows what he's doing. Don't make any mistake about him.

He's a capable man."

"I have no doubt of that, sir," replied Jack. "But if he had seen three years of war, as we have, he would never delay. Besides, he doesn't know these German submarines as well as I do. Neither do any of the Americans."

"Oh, yes they do," declared Frank.

"They do, eh?" exclaimed Jack. "Well, I'd like to know the name of one of them."

"His name," said Frank, "is Lieutenant Chadwick, and I think he knows just about as much about the U-Boats as you do; and he agrees with your ideas perfectly."

Jack smiled.

"That's right," he said. "I had forgotten you were a native of this land.

Well, here's hoping nothing happens before Secretary Daniels takes all necessary precautions."

The British ambassador left the lads at their hotel, and they returned at once to their rooms, where for several hours they discussed the situation.

"There is no use talking about it," said Frank at last. "Let's go to bed."