The newcomer was Lord Hastings, erstwhile distinguished secret service
agent and new commander in his British majesty's royal navy. Also,
though the fact was known to few, he was a distant cousin of the king
himself and one of the most highly trusted officers of the empire.

"Well, boys?" he repeated.

"Well, sir," said Frank, "we were just discussing the mystery of the
vanishing submarines."

Lord Hastings gazed at the lad in surprise.

"Vanishing submarines!" he repeated. "And tell me, how did you know
there were such things as vanishing submarines?"

"Why, Jack told me, sir," replied Frank.

"And how did you know it?" demanded Lord Hastings of Jack.

"I heard you and Mr. Churchill discussing it, sir," replied Jack.

Lord Hastings drew a long breath, evidently of relief.

"I didn't know we had been so indiscreet," he said, half to himself.
"However, there is no harm done, for I know you boys are to be trusted
not to repeat what you overhear. I'll tell you this, you two are among
the very few who know that any of the German submarines have been
accounted for."

"Then it is true?" asked Frank.