n hand. Perhaps we will be safe
for a while. I want to make a few more observations as to how they
manufacture the diamonds, and then, with what I already know, I'll have
the secret."

"And I'd like to make some scientific tests of the sides and bottom
rocks of the cave," spoke Mr. Parker. "I think it will bear out my
theory that the mountain will soon be destroyed."

"Well, you were right about Earthquake Island, and you may be right
about this mountain," said Tom, "but if it is going to be annihilated I
hope we get far enough away from it."

"We can keep our presence here a secret for a few more days, I think
that will be long enough," proceeded Mr. Jenks. "Then we will leave."

"And, in the meanwhile, they'll be searching for us," objected Mr.
Damon. "I wish that ghost-chap would come back and tell us what to do.
Bless my liver-pin, but we are going to be in considerable danger, I'm
afraid! Those men may capture us, and decide to make diamond dust from
us."

"Come on--hurry to the little cave," urged Tom. "Then we'll get ready to
defend ourselves."

"The main cave is a large one," said Mr. Jenks, "and there are many
hiding places in it. In fact, it is so large that it will take those
fellows several days to complete a circuit of it. By that time Bill
Renshaw may come back, and take us to some place in which they have
already searched for us. Then we'll be comparatively safe."

This thought was some consolation to them, as they made their way
through the dark passage, dimly illuminated by the lantern they had
rekindled, to the place where Bill had hidden them. They found things
as they had left them, and proceeded to get a meal, though Tom said it
would be best not to cook anything, or even to make coffee, for fear the
odors would enable the searchers to trail them.

So they ate cold food, glad to get that. Silently they sat about the
dimly-lighted cavern, and discussed the situation. True they might even
now retreat, going out of the entrance Bill had showed them, and so
escape. But Mr. Jenks felt that his mission was not completed yet, and
they all agreed to stay with him.

"For there are several points about making diamonds that are not
quite clear to me," he said. "I need to know how that steel box is
constructed, how the electrical switches are arranged, what kind of
lightning rods they use, and how they regulate the pressure. The other
things, and how to mix the ingredients, I already know."

"Then