For more than ten minutes he battered the lock, the steel digging into his wrists. He worked as quietly as possible, with long intervals between each attempt. For a while he was afraid the effort would be fruitless, as even the rusty steel seemed obdurate. Then, suddenly, he felt the lock give way. He eased his hands out of the cuffs with a sigh of relief.
"I'm free," he whispered to the others.
There were suppressed exclamations of delight.
"How are you going to get us out?" whispered Frank.
"I'll try to find the keys."
A low murmur from the other cave arrested his attention. Swiftly he leaned back against the wall. One of the gangsters was awake. The boys listened. They heard a movement in the outer cave, a jangling of keys, and then a heavy footstep.
Joe thrust his arms behind his back and feigned slumber. He could hear some one entering their cave.
Suddenly a bright light flashed in his face. The man on guard had come to inspect the captives and he brought with him a flashlight. Joe kept his eyes closed and breathed heavily. He hoped desperately that the man would not inspect their handcuffs.
The fellow appeared satisfied and in a few moments went away. Through narrowed eyelids Joe could see his dark form as he reached the passage between the two caves. He saw the round white circle of light shine for a moment on a small rock shelf in the passageway and he saw the guard reach up and toss a bundle of keys on the shelf. Then the man went on his way, switching out the light.
Joe's heart beat faster.