“Buster is right about that, for I remember it distinctly,” remarked Jack.

“That was the little room in school that Mr. Sparks allows the various clubs and organizations to use when they ask permission—the one on the second floor? Am I right, fellows?” Herb went on.

“Sure ye arre,” declared Jimmie. “Doan’t I just remember that we wint till the door ivery two minutes to say if the inemy would be sphyin’ around in the hall.”

“But there was no sign of them, you also remember that?” observed Jack, quickly.

“Niver a wan,” Jimmie hastened to reply.

“Then it would stand to reason that they didn’t overhear us talking. I know you couldn’t in the next room, for I’ve been in there during recitation, and the wall is dead. I only mention this, because that same day, after I left the rest of you down-town, I found that I’d forgotten a book I needed to study, and hurried back to the school. And I met Clarence coming along the street. He said he had been kept in by Miss Stryker to do a task. But it looks as though the leak could not have been at that time.”

“Somebody must have talked in their sleep,” suggested Josh, humorously.

“Perhaps some one in the post office got on to Jack receiving a letter from Clayton, and writing there,” Herb put in.

“Well, now,” remarked Jack, “there may be something in that idea; though just now I can’t think of anybody in the post office who would be that mean. I know all the clerks, and none of them have ever been thick with either Clarence or Joe.”

“Suppose we give the matter a rest,” said Herb, with an uneasy look toward Nick; for the fat boy was to be his partner during the coming cruise, and he feared lest Buster would get to brooding on the unjust suspicions that had been directed toward him, with the result that he must be forever speaking about it, and suggesting the most astonishing explanations of the riddle.