“Must be German,” said Jack.  “Call Lord Hastings.”

Frank did so and soon the commander of the U-6 appeared on deck.

Lord Hastings wasted no time in fixing the identity of the approaching vessels.

“Germans,” he said briefly.

“Yes; but where are they going?” Jack wanted to know.

“Probably intend another raid on the British coast,” returned Lord Hastings.  “By the time they are in waters patrolled by our ships it will be dark, and they hope to pass them in the night.  You haven’t forgotten the raid on Scarborough and Hartlepool, have you?”

“No, I haven’t,” said Jack.  “But I don’t figure they would have the temerity to try another.”

“They seem to have temerity enough to try anything,” declared Frank.  “However, I guess it’s up to us to stop this raid.”

“Right you are, Frank,” said Lord Hastings quietly.  “It’s up to us.”

“And how do you figure we are going to get all four of them?” demanded Jack.

“Well, with luck we might do it,” replied his commander.  “However, it would hardly be necessary for that.  If we can sink two the others will turn and run.”

“And shall we remain on the surface, sir?” asked Jack.

“No.  We’ll submerge until we are close to them.  Then we can come up safely enough, for they’ll believe us friends.  We can sink one and get down again in time.  Then, taking our calculations as to where they will be, we can come up again and have a try at another.  We may as well submerge now.”

Jack gave the order, and a few minutes later the U-6 was beneath the water, not even her periscope being allowed to show.  Here she remained until Lord Hastings believed the German battleships had approached close enough to be in range of the submarine’s torpedoes.  Then she came to the surface again.

Lord Hastings had gauged the distance accurately.  The German ships were now hard by and steaming swiftly forward.  As the U-6 sprang up from beneath the water, there was some excitement aboard the German vessels, which soon quieted, however, as the Germans made out the lines of the vessel and caught the German flag with their glass.

“We’re safe enough,” declared Jack.  “They take us for one of themselves.”

“Much to their sorrow,” said Frank.

“All ready below?” demanded Lord Hastings.

“All ready, sir,” replied Jack.

“Good.  Down with both of you then.  I’ll be down the moment the first torpedo has been fired, and we’ll have to submerge as quickly as possible.”

The lads obeyed Lord Hastings’ command and took their positions.

“Ready with No. 1 torpedo,” came Lord Hastings’ command from above.

“Ready, sir,” returned Jack, after a quick scrutiny.

“Ready with No. 3 torpedo,” shouted Lord Hastings.

“Ready, sir,” said Jack, and then exclaimed in an aside to Frank: 

“By Jove!  He’s going to try and get two of them at once.”