“Perry has been trying to shed a little more light on the Tower robbery,” explained Mr. Hardy. “But what is this clue you are talking of?”

“It isn’t about the robbery,” replied Frank. “Although it might have something to do with it, for all we know. It’s about the redheaded man who stole Chet’s car and who tried to hold up the steamboat ticket office.”

“What about him?”

“This!” said Frank, taking the fragment of red hair from his pocket and showing it to his father. “The fellow wore a wig.”

Mr. Hardy examined the little tuft of hair closely.

“Where did you find it?” he asked.

“In the wreckage of that smashed car.”