lic'; is it?"

"No," and Mr. Titus shook his head. "It isn't a question of
revolutions."

"But it's something!" insisted Mr. Damon. "Bless my ink bottle! but
it's something. As soon as I mention Peru, Tom, you and Mr. Titus eye
each other as if I'd said something dreadful. Out with it! What is it?"

"It's just--just a coincidence," Tom said. "But go on, Mr. Damon.
Finish what you have to say and then we'll explain."

"Well, I guess I've told you all you need to know for the present. I
went into this wholesale drug concern, hoping to make some money, but
now, on account of the trouble down in Peru, we stand to lose
considerable unless I can get back the cinchona concession."

"What does that mean?" Tom asked.

"Well, it means that our concern secured from the Peruvian government
the right to take this quinine-producing bark from the trees in a
certain tropical section. But there has been a change in the government
in the district where our men were working, and now the privilege, or
concession, has been withdrawn. I'm going down to see if I can't get it
back. And I want you to go with me."

"And I came here for very nearly the same thing," went on Mr. Titus.
"That is where the coincidence comes in. It is strange that we should
both appeal to Mr. Swift at the same time."

"Well, Tom's a valuable helper!" exclaimed Mr. Damon. "I know him of
old, for I've been on many a trip with him."

"This is the first time I have had the pleasure of meeting him,"
resumed the tunnel contractor, "but I have heard of him. I did not ask
him to go to South America for us. I only wanted to get some superior
explosive for my brother, who is in charge of driving the railroad
tunnel through a spur of the Andes. I look after matters up North here,
but I may have to go to Peru myself.

"As I told Mr. Swift, I had read of his invention of the giant cannon
and the special powder he used in it to send a projectile such a
distance. The cannon is now mounted as one of the pieces of ordnance
for the defense of the Panama Canal, is it not?" he asked Tom.

The young inventor nodded in assent.

"Having heard of you, and the wonderful explosive used in your big
cannon," the contractor went on, "I wrote to my brother that I would
try and get some for him.

"You see," he resumed, "this is the situation. Back in the Andes
Mountains, a couple of hundred miles east of Lima, the government is
building a short railroad line to connect two others. I