Mr. Hardy looked up at his sons and smiled.
"Well, you've shared your clues with me, so I suppose I may as well share some of my experience with you. What do you say if I go to the city and try to trace up some of these labels? This hat, for instance—" and he picked it up from the table, examining the band intently. "There is a label here. Of course, the hat may have been sold a long time ago, and it isn't likely that the man who sold it would remember who bought it. But there is always the chance that the store may not be far from where the fellow lives. You get my idea? And the coat, too. If we can find any trace of who bought the wig we may be able to connect up the other things as well."
"Gosh, I never thought of that!" admitted Frank.
"It's a slim chance, but, as I said before, we can't afford to overlook any chances. I'll take them to the city and see what I can do. It may mean everything and it may mean nothing. Don't be disappointed if I come back empty-handed. And don't be surprised if I come back with some valuable information."
Mr. Hardy tossed the wig, the coat and the hat into a club bag that was standing open near his desk. The great detective was accustomed to being called away suddenly on strange errands, and he was always prepared to leave at a moment's notice.
"Not much use starting now," he said, glancing at his watch. "But I'll go to the city the first thing in the morning. In the meantime, don't rest on your oars, as the saying is. Keep your eyes and your ears open for more clues. The case isn't over yet by any means."
Mr. Hardy picked up some papers on his desk, as a hint that the interview was over, and the boys left the library. They were in a state of high excitement, for they were confident now that they had made valuable progress in the case and they were sure that if the wig and the garments could be of any use at all toward locating the crook, Mr. Hardy would be the man to use them.
When they went to bed that night they could hardly sleep, so elated were they over their discovery near the abandoned roadway.
"He must have been a pretty smart crook," murmured Joe, after they had talked long into the night. "That idea about the wig was clever. I'll bet he was an experienced guy!"
"The smarter they are, the harder they fall," replied Frank. "It's the experienced crook that the police always look for. If this fellow has any kind of a record at all it won't take long for dad to run him down. I've heard dad say that there is no such thing as a clever crook. If he was really clever he wouldn't be a crook at all."