en let me warn you," went on Mr. Jenks, "that if you do hear it, you
will be so fascinated by it that I am sure you will want to cast your
lot in with mine, and aid me to get my rights, and solve the mystery.
And I also want to warn you that if you do, there is a certain amount of
danger connected with it."

"I'm used to danger," answered Tom, quietly. "Let me hear your story.
But first explain how you came to come here, and why you acted so
strangely at the jewelry store."

"Willingly. I tried to attract your attention at the store, because I
saw that you were going to buy a diamond, and I didn't want you to."

"Why not?"

"Because I want to present you with a beautiful stone, that will answer
your purpose as well or better, than any one you could buy. That will
prove my story better than any amount of words or argument. But I could
not attract your attention without also attracting that of the jeweler.
He became suspicious, gave chase, and I thought it best to vanish. I
hope no one was made to suffer for what may have been my imprudence."

"No, the lad whom Mr. Track caught was let go. But how did you happen to
come to Shopton?"

"To see you. I got your address from the owner of the yacht Resolute. I
knew that if there was one person who could aid me to recover my rights,
it would be you, Tom Swift. Will you help me? Will you come with me to
discover the secret of Phantom Mountain? If we go, it will have to be in
an airship, for in no other way, I think, can we come upon the place, as
it is closely guarded. Will you come? I will pay you well."

"Perhaps I had better hear your story," said the young inventor. "But
first let me suggest that we move farther away from the house. My
father, or Mr. Jackson, or the housekeeper, may hear us talking, and it
may disturb them. Come with me to my private shop," and Tom led the way
to a small building where he did experimental work. He unlocked the door
with a key he carried, turned on the lights, which were run by a storage
battery, and motioned Mr. Jenks to a seat.

"Now I'll hear your story," said Tom.

"I'll make it as short as possible," went on the queer man. "To begin
with, it is now several years ago since a poorly dressed stranger
applied to me one night for money enough to get a meal and a bed to
sleep in. I was living in New York City at the time, and this was
midnight, as I was returning home from my club.

"I was touched by the man's appearance, and gave hi