"The gum business is an old trick," said the manager. "It's a wonder it did not occur to you," he added, looking at the salesman. "When a thief comes into a store he sometimes carries a piece of adhesive gum like that," he explained to the policeman. "The first thing he does is to attach it to the bottom of the showcase, out of sight. Then he watches his chance, and if he is a sufficiently expert sleight-of-hand artist, he manages at some time during his inspection of the stones to convey a diamond to the gum and force it into it. When the diamond is afterward missed he cheerfully submits to a search, for the stolen stone is not on his person. Later he sends a confederate into the store to get the gum, under cover of an intention to make some kind of a purchase, other than diamonds, at that counter. In this case, it is quite clear to me that the lady was the man's confederate. I think I am fully justified in demanding that fellow's arrest at our risk. It is too bad that the woman got away, but I guess we'll be able to find her. You have her description, Dick," he said to the office boy. "Yes, sir. I'd recognize her on sight." "Now, officer, you may arrest that man and take him to the police station. We will go with you and make the charge," said the manager. "All right," said the policeman. "Come on, my man, you'll have to go with me." That settled the case as far as the pawnshop was concerned, and the party directly interested started with the officer and the prisoner for the Brooklyn Bridge station. The charge was made against the man, who gave his name as Jack Hurley, and he was locked up pending his removal to the Tombs prison. The manager, salesman and Dick then returned to the store. The former complimented the office boy on his smartness in bringing the thief to justice, which would result in the ultimate return of the valuable diamond to the store. Mr. Bacon, who had been informed of the theft of the stone, was duly put in possession of Dick's clever work toward its recovery and the punishment of the thief and, it was hoped, his accomplice. He sent for his office boy and added his compliments to those of the manager. "You're a clever boy, Dick," he concluded, "and I'll see that you lose nothing through your devotion to my interests. That's all." Dick got up and returned to his duty. CHAPTER VI.--Knocked Out.