"We thought perhaps it might be the sign of some secret society," said Hugh.
"Possibly so," agreed Mr. Cook. "Let's see; the same sign was on the paper you found in the old house, Heinrich got a note with the picture on it, and now this letter you picked up on the Wernbergs' porch had it too."
"And the handwriting was the same as on that postal card you got this morning," said Bob.
"I didn't see any picture on that though."
"No," agreed Bob. "Neither did I."
"I threw the card away," said Mr. Cook. "I was afraid your mother might find it and worry."
"Perhaps there won't be any more trouble, now that Mr. Wernberg is out of the way," suggested Bob. "If he was the leader of the gang, his burns will keep him in the hospital and out of mischief for some time to come."
"You didn't hear what happened this afternoon then?" asked his father.
"No, what?" demanded Bob and Hugh in one breath.
"You remember the railroad bridge, don't you?"