And, secretly, they wondered what Fenton Hardy would think if he knew how much work they had already put on the case and how much evidence they had already gathered, tending to indicate that the old mill on the Willow River was in some way connected with the activities of the counterfeiting gang.

"If you can get anything definite in this case," said Fenton Hardy, with a smile, "I'll be ready to admit that you have some abilities as detectives—"

"Fenton, don't encourage them," objected Mrs. Hardy.

"Nonsense, Laura," he replied. "If they want to be detectives and if they have the talent for it, you might as well try to keep water from running downhill as to stop them. They've done good work on two difficult cases already."

"And I have a hunch that we'll do something on this case, too," said Frank, with confidence.

CHAPTER XIX

The Rug Buyer

Two days later an event occurred that brought the activities of the counterfeiters much closer home.

Frank and Joe returned from school on Monday afternoon to find their mother in a state of great agitation. The moment they entered the house they could tell that something unusual had happened, for Mrs. Hardy was sitting by the living-room table gazing disconsolately at a great heap of bills in her lap.

"Where'd you get all the money, mother?" asked Frank, jokingly at first. But his expression became serious when he saw the anxiety and distress in Mrs. Hardy's face. Her fingers were trembling as she picked up the bills and put them on the table.