it is
that you're supposed to be prospecting for gold. There isn't any great
crime, or secret, in that, unless you're trying to get gold off land
that doesn't belong to you."

"No, it isn't gold, nor anything like gold," spoke Professor Wright, in
rather dreamy tones. "It is much more valuable than gold. I never
would have endured the hardships I have for mere gold."

"Nor I," said his partner, and then, for the first time the same
thought came to Nort and Dick--that these men might be lunatics,
obsessed with a strange idea, and that they were searching for
something that might be likened to a fading mirage.

The boy ranchers looked at one another. If this was the explanation
their position might be more dangerous than appeared. To be held
captives by men who were mentally irresponsible, aided by an
unscrupulous gang, of which Del Pinzo was a fair specimen, was not at
all a reassuring thought. But Nort and Dick were not the ones to give
up easily.

"Just what are you going to do?" asked Nort, when it was evident that,
unarmed as they were, resistance was out of the question for the time
being.

"Simply hold you here for a few days--not more than a week at most,"
answered Professor Blair.

"Suppose we don't stay?" asked Nort, sharply.

"Well, if you refuse to promise not to try to escape, we shall be
forced to detain you as best we can," was the calm reply. "But we have
no wish to use violence, and I think you will agree to submit quietly.
Be our guests, so to speak."

"What if our friends come to rescue us?" asked Dick.

"Well, we have thought of that," spoke Professor Wright. "If they come
we shall have to do our best to--er--persuade them to go away
again--that is unless we can bring our task to an end sooner than we
expect, and that is possible. If we can bring that about--make the
discovery we hope for--you will be at liberty to depart at that moment.
Otherwise you must stay here!"

"Well, we won't promise not to try to escape," declared Nort, hotly.
"We'll do our best, not only to get away, but to bring the police down
on you, or bring whatever authority they have out here. If you're
going to act this way we'll be justified in doing our worst!"

"Naturally," agreed Professor Wright, smoothly. "Now that we have been
made aware of your intentions we shall act accordingly. We shall be
obliged to keep you under guard, but I assure you that if you do not
act roughly neither will our guards.