“Probably not,” remarked Mr. Jenks.  “I don’t believe the ghost will venture down the dangerous trail after dark, and the gang may think that the warning given us by the two men on guard at the cave will be sufficient.  But if we don’t leave here by to-morrow I think we will have another visit from the thing in white.”

It was about an hour after this when Tom was collecting some wood in a pile nearer the fire, so as to have it ready to throw on, in case there was any alarm in the night, that he happened to look up toward the summit of the mountain.  A slight noise, as of loose stones rolling down, attracted his attention, and, at first, he feared lest another landslide was beginning, but a moment later he saw what caused it.

There, advancing down the steep and dangerous trail was the figure in white—­the phantom.  Instantly a daring plan came into Tom’s head.  Dropping the wood softly, he moved back out of the glare of the fire.

“Mr. Jenks!” he called in a whisper.

The diamond man, who was behind the tent, came toward Tom.

“What is it?” he asked.  Then, as he saw the ghostly visitor, he added:  “Oh—­the phantom again!  What’s it up to?”

“The same thing,” replied Tom, “but it won’t do it long, if my plan succeeds.”

“What plan is that, Tom?”

“I’m going to try to capture that—­that man—­or whatever it is.  Will you help?”

“Surely!”

“Then let’s work around behind it, while Mr. Damon and Mr. Parker come up from in front.  We’ll solve this part of the mystery, anyhow, if it’s possible!”

The two other men were soon told of the plan.  Meanwhile the thing in white had advanced slowly, until within a few hundred feet of the camp.  They could see now that it was no shaft of light, but some white body, shaped like a tall, thin man, draped in a white garment.  The long arms waved to and fro.  There was no semblance of a head.

“You and Mr. Parker go right toward it, slowly, Mr. Damon,” advised Tom.  “Mr. Jenks and I will make a circle, and get in back.  Then, if it’s anything alive we’ll have it.”

The “ghost” continued to advance.  Tom and the diamond man stole off to one side, their buckskin moccasins making no sound.  Mr. Damon and the scientist went boldly forward.

This movement appeared to disconcert the spirit.  It halted, waved the arms with greater vigor than before, and seemed to indicate to the adventurers that it was dangerous to advance.  But Mr. Damon and Mr. Parker kept on.  They wanted to give Tom and Mr. Jenks time enough to make the circuit.

Suddenly the stillness of the night was broken by a low whistle.  It was Tom’s signal that he and Mr. Jenks were ready.

“Come on!  Run!” cried Mr. Damon.

The scientist and the eccentric man leaped forward.

The “ghost” heard the whistle, and heard the spoken words.  The thing in white hesitated a moment, and then raised one arm.  There was a flash of lire, and a loud report.