The Mystery made a gesture, half of anger, half of reproof.

“You know not what you are saying,” he declared. “Tell me all, Frank Merriwell.”

Frank did so, in a very few words. The man listened till he had finished.

“Now,” exclaimed Diamond, “what have you to say to that? We both saw you at the window! We both saw you throw the bomb!”

“You may have thought you saw me.”

“Listen to that, Frank! What do you think of it for nerve?”

“It seems,” said the man, “that somebody who looked like me must have thrown this bomb.”

“That is thin! Why, do you think we would not know your clothes, your beard, your long black hair, your face? We are not fools! You are the man! You have pretended to be Merriwell’s friend, but to-day you sought to blow him to pieces!”

“I would sooner think of putting a gun to my head, and blowing out my own brains,” said the man solemnly.

“Bah! You cannot make us believe that now!”