ked 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 passed 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
document, broke the seal, and read aloud:

"Captain Tarlenhein,

"Commanding H.I.S. U-16:

"Proceed immediately, under command of Admiral Schuler, to Dover
Bay, joining submarine flotilla there, to proceed to the Thames
for attack British fleet. Flotilla to gather mile off Dover,
midnight, Thursday.

(Signed) "SEIBERT."

"I should say that is plain enough," said Lord Hastings, looking up.

"Rather, sir," agreed Frank. "All we have to do is to be at a certain
spot at a certain time."

"That's it. And the beauty of it is we do not go with any other vessel.
I suppose Admiral Seibert deems it advisable for each vessel to make her
way there separately, coming to the surface at the appointed time."

"And shall we be there, sir?" asked Frank.

"Rather," replied Lord Hastings dryly. "First, however, we shall have to
find time to run even closer to Dover, take a trip ashore, and notify
the Admiralty. Then perhaps we can arrange a little surprise for our
friends the enemy."

"That's the way, sir," said Frank enthusiastically. "And I would suggest
that the sooner we get under way the better. It may not be so easy to
get ashore without being sent to the bottom by one of our own ships or
forts."

"Very well," replied Lord Hastings. "You may give the word to proceed at
eighteen knots, Mr. Templeton."

Jack gave the order, and the U-16 moved off in the night.

Having obtained Lord Hastings' permission, Frank and Jack decided to
turn in. They made