Calling a young fellow who was at work near by to occupy
the gate-house, Tom led Mr. Titus toward the Swift
homestead, and, a little later, ushered him into the
library.

"Now I'll listen to you," the youth said, "though I can't
promise to aid you."

"I realize that," returned Mr. Titus. "This is a sort of
last chance I'm taking. My brother and I have heard a lot
about you, and when he wrote to me that he was unable to
proceed with his contract of tunneling the Andes Mountains
for the Peruvian government, I made up my mind you were the
one who could help us if you would."

"Tunneling the Andes Mountains!" exclaimed Tom.

"Yes. The firm represented by my brother and myself have a
contract to build a railroad for the Peruvian government. At
a point some distance back in the district east of Lima,
Peru, we are making a tunnel under the mountain. That is, we
have it started, but now we can't advance any further."

"Why not?"

"Because of the peculiar character of the rock, which
seems to defy the strongest explosive we can get. Now I
understand you used a powder in your giant cannon that--"