"Then I'll have a try at it," said Chester. "Be ready to crouch close to the side of the pit when I give the word. I'll come down on top of you and we'll trust to luck that the debris falls clear."
"All right," said Hal. "Yell when you're ready."
Again Chester tested the covering with his hands. At last he struck a spot where he could obtain a grip. He decided to throw his weight on it and see if it would come down. He took a firm hold and then called:
"All right, Hal! Stoop quickly!"
CHAPTER X
UNEXPECTED VISITORS
Came a low, rumbling sound from overhead and a shower of dirt poured down on Hal as he crouched in his corner. Chester still swung to and fro from above. The lad felt something give, and believing that the mass above was about to fall, he dropped quickly alongside Hal and buried his face in his arms.
But nothing happened.
Directly Chester rose to his feet.
"I thought it was coming," he said to Hal. "Guess I didn't hang on long enough. I'll have another try. Lend me your shoulders again."