“An’ thar they air to-day.”

Frank experienced a chill.

“That is a horrible thing,” he declared. “I suppose unsuspecting travelers are apt to walk right into the place?”

“Certain. I know of at least three men who hev crossed ther valley safely.”

“How did they do it?”

“Oh, thar’s days when ther gases don’t come up, I suppose.”

Frank was thoughtful a moment.

Barney and Pomp had been listening with the deepest of interest.

“How far is it from here to the Satan’s Hole?” Frank finally asked.

“Oh, a matter of fifty miles I reckon,” replied Beaver Bill.