“How was the safe opened?”
“It was either opened by someone who knew the combination or else by a very clever crook. It wasn’t dynamited at all. I’m going up to the house in a few minutes. Mr. Applegate is to call for me.”
“Can’t we go along?” asked Joe eagerly.
Mr. Hardy looked at his sons with a smile.
“Well, if you are so anxious to be detectives, I suppose it is about as good a chance as any to watch a crime investigation from the inside. If Mr. Applegate doesn’t object, I suppose you may come along.”
In a few minutes an automobile drew up before the Hardy home. Mr. Applegate was sitting in the rear seat, resting his chin on his cane. When Mr. Hardy mentioned the boys’ request he merely grunted assent, so Joe and Frank clambered into the car with their father. They were tremendously excited at the prospect of being “on the inside” in the mysterious case.
While the car bowled along over the city roads toward the Tower Mansion that was gloomily silhouetted against the sky, Mr. Hardy and Mr. Applegate discussed the robbery.
“I don’t really need a detective in this case,” snapped Hurd Applegate. “Don’t need one at all. It’s as clear as the nose on your face. I know who took the stuff. But I can’t prove it.”
“Whom do you suspect?” asked Fenton Hardy.
“Only one man in the world could have taken it. Robinson!”
“Robinson?”
“Yes. Henry Robinson—the caretaker. He’s the man.”
The Hardy boys looked at one another in consternation.
Henry Robinson, the caretaker of the Tower Mansion, was the father of one of their closest chums. Perry Robinson, nicknamed “Slim,” was to have accompanied them on their jaunt to the woods that day but had failed to appear. The reason was now evident.
But that Henry Robinson should be accused of the robbery seemed absurd. The boys had met Slim’s father and he had appeared to them as a good-natured, easygoing man, the soul of truth and honesty.
“I don’t believe it,” whispered Frank.
“Neither do I,” returned his brother.
“What makes you suspect Robinson?” asked Mr. Hardy of Hurd Applegate.
“He’s the only person besides my sister and me who ever saw that safe opened and closed. He could have learned the combination if he kept his eyes and ears open. I believe he did.”
“But is that your only reason for suspecting him?”
“More than that. This morning he paid off a note at the bank. It was a note for nine hundred dollars, and I know for a fact that he didn’t have more than one hundred dollars to his name a few days ago. The Robinsons have been hard up, for they had sickness in the family last winter and Henry Robinson has had a hard time meeting his debts since then. Now where did he raise nine hundred dollars so suddenly?”
“Perhaps he has a good explanation,” said Mr. Hardy mildly. “It doesn’t do to jump at conclusions.”
“Oh, he’ll have an explanation all right!” sniffed Mr. Applegate. “But it will have to be a mighty good one to satisfy me.”
“Luckily, he’ll not have to satisfy Mr. Applegate, but will have to convince a jury—if it gets that far,” whispered Joe in his brother’s ear.
The automobile was speeding up the wide driveway that led to Tower Mansion, and within a few minutes it drew up at the front entrance. Mr. Applegate dismissed the driver, and Mr. Hardy and the two boys accompanied the eccentric man into the house.
Nothing had been disturbed in the library since the discovery of the theft. Mr. Hardy examined the open safe, then drew a magnifying glass from his pocket and with minute care inspected the dial of the combination lock. Then he examined the windows, the doorknobs, all places where there might be fingerprints. At last he shook his head.
“A smooth job,” he observed. “The fellow must have worn gloves. Not a fingerprint in the room.”
“No need of looking for fingerprints,” said Applegate. “It was Robinson—that’s who it was.”
“Better send for him,” advised Mr. Hardy. “I’d like to ask him a few questions.”
Mr. Applegate rang for one of the servants and instructed him to tell Mr. Robinson he was wanted in the library at once. Mr. Hardy glanced at the boys.
“You had better wait in the hallway,” he suggested. “I want to ask some questions, and it might embarrass Mr. Robinson if you were here.”
The lads readily withdrew, and in the hallway they met Henry Robinson, the caretaker, and his son Perry. Mr. Robinson was calm but pale, and at the doorway he patted his son on the shoulder.
“Don’t worry, son,” he said. “It’ll be all right.” With that he entered the library.
Slim Robinson turned to his two chums.
“My dad is innocent!” he cried.
VIII
The Arrest
There was something in Perry Robinson’s tone that made Frank and Joe extremely sorry for their chum, for it seemed that the boy realized that the case looked black against his father.
Although the Hardy lads realized that it was only natural that Perry should stand up for his father, they shared some of his conviction that Mr. Robinson was not guilty.
“Of course he’s innocent,” agreed Frank. “He’ll be able to clear himself all right, Perry.”
“But everything looks pretty black against him,” said Perry, who was pale and shaken. “Unless your father can catch the real thief I’m afraid Dad will be blamed for it.”
“Everybody knows your father is honest,” said Joe consolingly. “He has a good record—even Applegate will have to admit that.”
“A good record won’t help him very much if he is blamed for this and can’t clear himself. And Dad admits that he did know the combination of the safe.”
“He knew it?”
“Accidentally. He was cleaning the library fireplace one day when he found a slip of paper with numbers marked on it. The combination was so simple that anyone could remember it if he read it once. Dad didn’t realize what it was until he had studied it a while, and then
