Them's my instructions. I'm
supposed to be on guard, and scare away strangers. I'm tired of the
work, too, for I don't get my share, and those other fellows, in the
cave, get all the money from the diamonds."

Tom Swift uttered an exclamation. A sudden plan had come to him. Quickly
he whispered to Mr. Jenks:

"Make a friend of this man if possible. He evidently is dissatisfied.
Offer him a sum to show us another way into the cave, and we may yet
discover the secret of the diamond makers."

"I will," declared Mr. Jenks, quietly. Then, turning to Renshaw, he
added:

"Bill, come over here. I want to have a talk with you. Perhaps it will
be to our mutual advantage."

He led the former phantom to one side, and for some time conversed
earnestly with him. Mr. Jenks told the story of how he had been deceived
by Folwell and the others who were at the head of the gang of diamond
makers. The rich man related how they had taken his money, and, after
promising to disclose the secret process to him, had broken faith, and
had drugged him, afterward taking him out of the cave.

"I want only my rights, and that for which I paid," concluded Mr. Jenks.
"Now, I gather that these men haven't treated you altogether fairly,
Bill."

"Indeed they haven't. I helped 'em to the best of my ability, and all
I get out of it is to stay out on this lonely side of the mountain,
and play ghost. They owe me money, too, and they won't pay me, either,
though they have lots, for they sold some diamonds lately."

"Then they are still making diamonds?" asked Mr. Jenks, eagerly. "Have
you seen them? Do you know the secret?"

"No, I don't know it, for they won't let me in on it. I'm always sent
out of the cave just before they make the gems. But I know they've made
some lately, and have sold 'em. I want my share."

"Look here!" exclaimed Mr. Jenks, quickly, wishing to strike while the
iron was hot. "I'll make you a proposition. Show us how to get into that
cave, unknown to the diamond makers, and I'll pay you twice what they
agreed to. Is it a bargain?"

Bill Renshaw considered a moment. Then he thrust out his hand, clasped
that of Mr. Jenks, and exclaimed:

"It is. I'll take you into the cave by an entrance that's seldom used.
There are four ways to get in. The one where the two men drove you back
is the rear one. The front one is on the other side of the mountain, but
it's so well concealed that you'd never find it. But I can take you to
one wh