"He ducked in somewhere, all right," Ned answered. "I wish we could
get across there without exhibiting ourselves to the whole country."

"I believe the boy that rode the mule is over there!" Frank
suggested.

"Yes; and he's probably been picked up by the moonshiners," Ned
agreed. "We've got to get over there, so here goes!"

The boys went across the streak of moonlight like a couple of
flashes, and drew up at the mouth of the cavern. So far as they could
determine no one had observed them.

They crept to the very back of the cave and huddled close together,
listening.

"Not a soul in sight!" Frank whispered. "That might have been a
ghost!"

"Do ghosts rattle metal?" asked Ned.

There followed another silence, and then the clink of metal came
clearer to the ears of the listening boys.

"Where does it come from?" asked Frank. "There's not a crack in sight
in this rock."

A puff of soft coal gas wafted into the cave, causing the boys to
hold their breaths. Then, in spite of all he could do to prevent it,
Frank sneezed.