their secret whereabouts, I received mysterious and anonymous warnings to stop.
"But I did not. I came East, and tried to get help to discover the cave of the diamond makers, but I was unsuccessful. I needed an airship, as I said, and no person who could operate one, would agree to go with me on the quest. Again I received a warning to drop all search for the diamond makers, but I persisted, and about a week ago I found I was being shadowed."
"Shadowed; by whom?" asked Tom.
"By a man I never remember seeing, but who, I have no doubt, is one of the diamond-making gang."
"Do you think he means you harm?"
"I'm sure of it. That is the reason I have to act so in secret, and come to see you at night. I don't want those scoundrels to find out what I am about to do. On my return from Earthquake Island, I again endeavored to interest an airship man in my plan, but he evidently thought me insane. Then I thought of you, as I had done before, but I was afraid you, too, would laugh at my proposition. However, I decided to come here, and I did. It seemed almost providential that my first view of you was in a jewelry shop, looking at diamonds. I
