“I see that plain enough. I am inclined to think. Jack, that you made a big mistake in giving that chap the location of the Sea King.”

“You do? Why?”

But as he spoke there came into Jack’s mind an uncomfortable recollection of what Jupe had said about wreckers.

“I don’t know just why,” was Tom’s frank response; “didn’t you ever have a feeling that somehow something you had done had been,—quite unintentionally,—a bad blunder?”

“I know what you mean. I wish to goodness we knew who this X. Y. Z. was,—or is.”

“Easy to find out.”

“Easy to find out!” echoed Jack with a fine note of scorn, “about as easy as—as——”

“Translating that cipher,” broke in Tom. “If we can read it we may have a good clew to Mister X. Y. Z. and his doings.”

Jack laughed aloud.

“Yes, ‘if,’” he said mockingly, “and if——”