Finally Joe said, “Thanks. For a second I sure thought I was going to end my career as a detective right here!”

“I guess you can also thank our gym teacher for the tricks he taught you on the bars,” Frank remarked. “You must have grabbed those spindles with flash-camera speed.”

Presently the boys turned their eyes upward. An expression halfway between a grin and a worried frown crossed their faces.

“Mr. Applegate,” Joe remarked, “isn’t going to like hearing we ruined his trap door.”

“No. Let’s see if we can put it back in place.”

The boys climbed the stairway and examined the damage. They found that the hinges had pulled away from rotted wood. A new piece would have to be put in to hold the door in place.

“Before we go downstairs,” said Joe, “let’s look out on the roof. We thought maybe the loot was hidden there. Remember?”

Frank and Joe climbed outside to a narrow, railinged walk that ran around the four sides of the square tower. There was nothing on it.

“Our only reward for all this work is a good view of Bayport,” Frank remarked ruefully.

Below lay the bustling little city, and to the east was Barmet Bay, its waters sparkling in the late afternoon.