“Yes, sir, we can,” interrupted Jack.

Here Colonel Masterson took a hand again.  He spoke to Lord Hastings.

“What shall we do with them?” he asked.

“That, colonel, is for you to decide,” was Lord Hastings’ reply.

“Do you think it necessary to call a court martial?” continued the colonel.

“In view of the evidence we have, I should say not,” returned Lord Hastings.

“And still,” said Colonel Masterson, half to himself, “it seems to me that every man should be given a chance.”

In the minds of the two boys now there was not the slightest doubt that they were in as perilous a situation as they had ever faced.

“Lord Hastings,” said Jack quietly, “I assure you you are all mistaken.  However, we shall protest our innocence no longer, for I see it would be useless.”

And then the two lads were treated to one of the surprises of their lives.  Lord Hastings’ stern expression gave way to a smile, and he strode quickly toward them and extended a hand to each.

“Surely,” he said, “you didn’t think I doubted you.”

The lads were too stunned to say a word.

“I just wanted to teach you a little lesson,” continued Lord Hastings.  “In the future, perhaps you will neither fall short nor go beyond your orders.  I ordered you to Gravesend.  You should not have gone beyond.”

“But Davis, sir?” exclaimed Frank.

“As long as you were here, apparently prisoners,” was the reply, “I simply used you to advantage.  Davis is a German spy.”

CHAPTER IV.

Strange warfare.

It was the following night.

Clad in heavy oilskins, Frank and Jack stood in the bow of the large, high-powered motorboat as it sped down the Thames in the darkness.  Not a light was visible anywhere and it was impossible to see a yard ahead.  But in spite of this, the boat fairly flew over the water; for the strong hand of Lord Hastings was on the wheel and there was not a spot in the river with which he was not familiar.

“Whew!” said Jack, as he turned about to shield his face from the icy spray.  “This is what I call taking a long chance, if you ask me.”

“I should say so,” replied Frank, raising his voice to a shout to make himself heard above the sound of the whistling wind.  “Wonder how long we are going to keep this up?”

“Don’t know,” responded Jack.  “But I don’t feel very comfortable.  This is too fast for me.”

“Particularly when you can’t see where you are going,” Frank agreed.

Both became silent and peered into the intense darkness ahead.

For possibly half an hour the motorboat continued its terrific speed; and then it slowed down abruptly.  The two boys heard Lord Hastings call them.  They felt their way to where he stood by the wheel, for it was impossible to see.