When they left the office it was with little hope that the thief or the car would be found. Their misgivings were justified. When they returned to see Chief Collig that night they learned that no word had been received concerning the yellow roadster from any of the outlying towns or villages and that despite a diligent search conducted by Detective Smuff and other members of the Bayport force, the roadster had not been located in the city. CHAPTER V CHET'S AUTO HORN Fenton Hardy, the internationally famous detective, was reading in the library of his home that evening when his sons tapped on the door. Although he was a busy man, Mr. Hardy was not the type of father who maintains an air of aloofness from his family, the result being that he was on as good terms with his boys as though he were an elder brother. "Come in," he shouted cheerfully, putting aside his book, and when Frank and Joe entered the room he motioned to a deep leather sofa near the window. "Sit down. What have you been doing all day? Burning up all the roads in the country, I suppose?" He grinned amiably at them and puffed vigorously at his pipe. "Well, we didn't travel very far to-day, dad," Frank replied. "We were--well, we--we were--" "Investigating," prompted Joe. "Aha!" exclaimed Mr. Hardy, in mock surprise. "So my sons were investigating, eh? What was it? A murder? A plot to blow up the White House? A train wreck? Something big, I hope." "No--not quite that bad," admitted Frank. "It was a car theft." Mr. Hardy shook his head. "I'm disappointed in you," he said solemnly. "I really am. To think that sons of mine should investigate a car theft. I thought you wouldn't bother about anything less than a murder!" His eyes twinkled, and the Hardy boys, who were accustomed to their father's good-natured banter, smiled back at him. "We weren't just practicing detective work, dad," explained Frank. "You see, Chet Morton's roadster was stolen this morning." "Is that so!" exclaimed Mr. Hardy, genuinely concerned. "Why, that's too bad. Chet was mighty proud of that car, wasn't he?" "Yes, he was. And it hasn't been found yet." "No trace of the thief?" "He tried to hold up the steamboat ticket office after he stole the car." Mr. Hardy whistled. "Why you _have_ been on a case worth while. Tell me all about it." He settled back in his chair while his sons told him the story of the day's doings. When they told of the difference of opinion as to the color of the man's hair he did not laugh with them, as they had expected, over the argument between Harrity and Mr. Brown. On the contrary, he knitted his brows and his face wore a serious expression. "It wasn't any ordinary auto thief you were dealing with," he said slowly. "I've no doubt the man who tried to rob the ticket office and the man who almost ran you down on the shore road were one and the same. And the same man stole Chet Morton's car."