“Perfectly sure,” replied the professor. “I only wish I were not. But I had a valuable package in here yesterday, and now it’s gone.”

“Why, nothing of that kind has ever happened before,” said Sluper, much agitated. “Did the thief take anything else?”

“No,” replied Professor Raymond. “And it was no outsider that took the package. There was a little money in the desk, and any ordinary thief would have taken that. Besides, the papers that were taken would have been of no value to any one outside the school. They were the examination slips for the next algebra test. Sluper, we’ve a thief right here in Rally Hall.”

“I’d be sorry to think that, sir,” said the dismayed janitor. “I can’t think of any of the boys who might do such a thing.”

“But some one of them did, just the same,” replied the professor. “See here,” and he showed the janitor the shaving of wax.

“That proves that it was all planned beforehand,” he said. “An outside thief would have had a skeleton key, or simply pried it open with a jimmy. But somebody has taken a wax impression of the lock and had a key made to fit.

“Keep this thing perfectly quiet for a time,” the teacher cautioned. “Be on the watch for anything suspicious you may see or hear among the boys. And I want you to go down town to Kelly’s, the locksmith. Get into a talk with him, and bring the conversation round to the subject of duplicate keys, and how they’re made. If he’s done anything of that kind lately, he may drop a hint of it. He’d have no reason to keep quiet, for he’s an honest man and wouldn’t do a crooked thing. If he’s made such a key, the thief has given him some plausible reason for getting it made. Find out anything you can, and let me know at once. But, above all things, don’t let the matter get out.”

The janitor, badly confused, went away on his mission, while Professor Raymond sought out Dr. Rally to lay the matter before him. If it had been an ordinary case, he would have acted on his own discretion. But this was altogether too serious, involving as it did the good name of one of the scholars, and, to a certain extent, the reputation of the school itself.

He found the doctor in his office, and laid the matter before him, giving him all the details that he knew himself and telling of his instructions to the janitor.

Dr. Rally was white hot with amazement and indignation.