of explosive. That used for my giant cannon would merely
crumble the hard rock for a short distance."

"Then will you accept the contract, and help us out?"
asked Mr. Titus eagerly. "We will pay you well. Will you
come to Peru and look over the ground?"

"And kill two birds with one stone, and come with me
also?" put in Mr. Damon.

Tom pondered for a moment. He was about to answer when the
tunnel contractor, who was looking from the library window,
suddenly jumped from his chair crying:

"There he is again! Once more dogging me!"

As he rushed from the room, Tom and Mr. Damon had a
glimpse of a face at one of the low library windows--a face
that had an evil look. It disappeared as Mr. Titus ran from
the room.




Chapter IV

Tom's Experiments