"Bless my thermometer! Bless my porous plaster!"

"We found," resumed Mr. Titus, "after we had bored for a
considerable distance into the mountain, a mass of volcanic
rock which is so hard that our best diamond drills are
dulled in a short time, and the explosives we use merely
shatter the face of the cutting, and give us hardly any
progress at all.

"It was after several trials, and when my brother found
that he was making scarcely any progress, compared to the
energy of his men and the blasting, that he wrote to me,
explaining matters. I at once thought of you, Tom Swift, and
your powerful explosive, for I had read about it.

"Now then, will you sell us some of your powder--explosive
or whatever you call it--Mr. Swift, or tell us where we can
get it? We need it soon, for we are losing valuable time."

Mr. Titus paused to draw on a piece of paper a rough map
of Peru, and the district where the tunnel was being
constructed. He showed where the two railroad lines were,
and where the new route would bring them together, the
tunnel eliminating a big grade up which it would have been
impossible to haul trains of any weight.

"What do you say, Mr. Swift?" the contractor concluded.
"Will you let us have some of your powder? Or, better still,
will you come to Peru yourself? That would suit us
immensely, for you could be right on the ground. And you