"Just came from school," they told her. "We didn't meet anybody on the way." Suddenly Frank glanced at the floor. "Why, you've sold the rug!" he exclaimed, in surprise. The living-room floor had hitherto been covered by a valuable old Persian rug, as soft as moss. It had been bought by Mr. Hardy when on a trip to the city, but Mrs. Hardy had never cared for it. Fenton Hardy had thought to surprise his wife when he brought the rug home, but in a masculine indifference to color schemes he had neglected to see to it that the rug matched the rest of the room. Its color was not what Mrs. Hardy wanted, and inasmuch as the rug had been purchased at an exclusive sale, they had found it impossible to exchange it at the time. Mrs. Hardy had always said that if she had an opportunity she would get rid of the rug and purchase something different. However, the opportunity was long in coming. Although she had received several offers for it, none of these had been for more than five hundred dollars. "And," as she said, "I refuse to sell a nine hundred dollar rug for that price." Now, as the Hardy boys noticed, the rug was gone. "How much did you get for it?" asked Joe eagerly. "I gave it away." "Gave it away?" they exclaimed. Mrs. Hardy nodded. "Not intentionally. I've been cheated." "How?" demanded Frank quickly. Mrs. Hardy motioned toward the money. "I've just been to the bank to deposit that money--" "You don't mean to say it's counterfeit?" "So the bank cashier told me." Frank sat down heavily in the nearest chair. "Well I'll be gosh-hanged!" he exclaimed. "How did this happen? How much did they sting you for?" "Eight hundred dollars," answered Mrs. Hardy gravely. Joe whistled in surprise. "How did it happen?" "He came here shortly after you boys left for school," began Mrs. Hardy. "It must have been a little before two o'clock." "Who came here?" "The rug buyer. He was a queer little fellow, very short and dark. He was a foreigner, you could tell by his appearance. He didn't speak very good English. He was dark and swarthy, with little, keen black eyes. He came up to the front door and asked me if I wanted to buy rugs. When I told him that I didn't want to buy he asked if I had any to sell. He said he was a traveling rug merchant and that he went from city to city, buying and selling and trading rugs." "So you told him about the living-room rug?" suggested Frank. "I just thought of it then, and I thought it might be a good chance to get rid of it and perhaps get a better rug in its stead. I mentioned that I had a rug that I might sell, but I told him I didn't think he could pay the price." "And he asked to see it anyway?" Frank went on.