heard he had paid dad, so he made my father promise to say nothing. And when my dad makes a promise he keeps it."
The boys looked at one another. To tell the truth, few of them had thought of the affair of the nine hundred dollars, but now that it was recalled to them they realized that here was the final angle of the Tower Mansion mystery cleared up at last. They cheered Slim to the echo, they pounded on the table with their knives, and when Hurd Applegate came in to see what the racket was about they gave him three cheers and made him sit at the head of the table.
And that ended the affair of Tower Mansion, but it did not end the career of the Hardy boys as amateur detectives. They were soon to be called on to help solve another mystery, and the story of their adventures in this case will be told in the next volume of this series, entitled "The Hardy Boys: The House on the Cliff."
"Speech! Speech!" the boys were shouting to Hurd Applegate.
The old stamp collector got up, smiling.
"It's been a long time since there's been a crowd of boys in Tower Mansion," he said. "I've been in danger of forgetting that I was ever young once myself. So I want you to come back—often. I want you to know that Tower
