ing out of the secret chamber. He mentioned his suspicion to Joe.
"But how could they pile the boxes up there after they went out?" his brother questioned.
"This gang are smart enough for anything. Let's move these boxes away."
He seized the topmost box. It was very light and he removed it from the top of the pile without difficulty.
"I thought so!" exclaimed Frank, with satisfaction.
For the light revealed the top of a door which had hitherto been hidden from view.
The boys lost no time in moving the rest of the boxes, and the entire door was soon in sight. Then the boys discovered how it was possible for the boxes to be piled up in such a position in spite of the fact that the smugglers had left the chamber and closed the door behind them.
Attached to the bottom of the door was a small wooden platform that projected out some distance over the floor of the cave and on this platform the boxes had been piled.
"They are kept there all the time, as a blind," he said. "Whenever any one leaves the cave and closes the door the boxes swing in with the platform and it looks as though they were piled up on the floor."
The ingenuity of the contrivance won their reluctant admiration.
