"Surely you guess," protested Tom.

"Why, it seems that Don Luis is having ore from another mine brought
down in the dead of the night."

"Yes, and a lot of it," Tom went on. "Did you notice how much
rich ore there was in each tunnel to-day? And did you notice,
too, that when blasts were made with us looking on, no ore worthy
of the name was dug loose? Don Luis has been spending a lot of
money for ore with which to salt his own mine!"

"Salting" a mine consists of putting the gold into a mine to be
removed. Such salting gives a worthless mine the appearance of being
a very rich one.

"But why should Don Luis want to salt his own mine?" muttered
Harry.

"So that he can sell it, of course!"

"But he doesn't want to sell."

"He says he doesn't," Tom retorted, with scorn. "This afternoon,
you remember, he got me to copy a report in English about his
mine and then he wanted us to sign the report as engineers. Doesn't
that look as though he wanted to sell? Harry, Don Luis has buyers
in sight for his mine, and he'll sell it for a big profit provided
he can impose on the buyers!"