Tom looked pleased at this order, and soon he and all the men in the little party were busy taking out the electrical apparatus, and moving it farther inland.

"What are you going to do with it, Tom?" asked Mr. Damon, in a low voice, as he a.s.sisted the young inventor to carry a small dynamo, that was used for operating the incandescent lights.

"I hardly know myself. I have a half-formed plan in my mind. I may be able to carry it out, and I may not. I don't want to say anything until I look over the machinery, and see if all the parts which I need are here. Please say nothing about it."

"Bless my toothpick! Of course, I'll not," promised Mr. Damon.

When the removal of most of the machinery of the wrecked airship had been completed, Mrs. Nestor exclaimed:

"Well, since you are moving that out of harm's way, don't you think it would be a good idea to change our camp, also? I'm sure I'll never sleep a wink, thinking that part of the island may fall into the ocean at any moment in the night, and create a wave that may wash us all out to sea. Can't we move the camp, Mr. Swift?"

"No reason why we can't," answered the lad, smiling. "I think it would be a good plan to take it farther back. We are likely to be here some time, and, while we are about it, we might build more complete shelters, and have a few more comforts."

The others agreed with this idea, so the little shacks that had been erected were taken down, and moved to higher ground, where a better outlook could be had of the surrounding ocean. At the same time as safe a place as possible, considering the frequent earthquakes, was picked out--a place where there were no overhanging rocks or cliffs.

Three huts were built, one for the two ladies, one for the men, and third where the cooking could be done. This last also held the food supplies and stores, and Tom noted, with satisfaction, that there was still sufficient to eat to last over a week. Mr. Fenwick had not stinted his kitchen stores.

This work done, Captain Mentor and Mate Fordam went to the highest part of the island, where they erected a signal, made from pieces of canvas that had been in the life boat. The boat itself was brought around to the new camp, and at first it was hoped that it could be repaired, and used. But too large a hole had been stove in the bottom, so it was broken up, and the planks used in making the shacks.

This work occupied the better part of two days, and during this time, there were no more earthquakes. The castaways began to hope that the island would not be quiet for a while. Mrs. Anderson and Mrs. Nestor a.s.sumed charge of the "housekeeping" arrangements, and also the cooking, which relieved Tom from those duties. The two ladies even inst.i.tuted "wash-day," and when a number of garments were hung on lines to dry, the camp looked like some summer colony of pleasure-seekers, out for a holiday.

In the meanwhile, Tom had spent most of his time among the machinery which had been taken from the airship. He inspected it carefully, tested some of the apparatus, and made some calculations on a bit of paper. He seemed greatly pleased over something, and one afternoon, when he was removing some of the guy and stay wires from the collapsed frame of the WHIZZER, he was approached by Mr. Barcoe Jenks.

"Planning something new?" asked Mr. Jenks, with an attempt at jollity, which, however, failed. The man had a curious air about him, as if he was carrying some secret that was too much for him.

"Well, nothing exactly new," answered Tom. "At best I am merely going to try an experiment."

"An experiment, eh?" resumed Mr. Jenks, "And might I ask if it has anything to do with rescuing us from this island?"

"I hope it will have," answered Tom, gravely.

"Good!" exclaimed Mr. Jenks. "Well, now I have a proposition to make to you. I suppose you are not very wealthy, Mr. Swift?" He gazed at Tom, quizzically.

"I am not poor," was the young inventor's proud answer, "but I would be glad to make more money--legitimately."

"I thought so. Most every one would. Look here!"

He approached closer to Tom, and, pulling his hand from his pocket, held it extended, in the palm were a number of irregularly-shaped objects--stones or crystals the lad took them to be, yet they did not look like ordinary stones or crystals.

"Do you know what those are?" asked Mr. Jenks.

"I might guess," replied Tom.

"I'll save you the trouble. They are diamonds! Diamonds of the very first water, but uncut. Now to the point. I have half a million dollars worth of them. If you get me safely off this island, I will agree to make you a quarter of a million dollars worth of diamonds!"

"Make me a quarter of a million dollars worth of diamonds?" asked Tom, struck by the use of the work "make."

"Yes, 'make,'" answered Mr. Jenks. "That is if I can discover the secret--the secret of Phantom Mountain. Get me away from the island and I will share my knowledge with you--I need help--help to learn the secret and help to make the diamonds--see, there are some of the first ones made, but I have been defrauded of my rights--I need the aid of a young fellow like you. Will you help? See, I'll give you some diamonds now. They are genuine, though they are not like ordinary diamonds. I made them. Will you--"

Before Tom could answer, there came a warning rumble of the earth, and a great fissure opened, almost at the feet of Mr. Jenks, who, with a cry of fear, leaped toward the young inventor.

CHAPTER XIX

SECRET OPERATIONS

"Help me save this machinery!" yelled Tom, whose first thought was for the electrical apparatus. "Don't let it fall into that chasm!"

For the crack had widened, until it was almost to the place where the parts of the wrecked airship had been carried.

"The machinery? What do I care about the machinery?" cried Mr.

Jenks. "I want to save my life!"

"And this machinery is our only hope!" retorted Tom. He began tugging at the heavy dynamos and gasolene engine, but he might have saved himself the trouble, for with the same suddenness with which it opened, the crack closed again. The shock had done it, and, as if satisfied with that phenomena, the earthquake ceased, and the island no longer trembled.

"That was a light one," spoke Tom, with an air of relief. He was becoming used to the shocks now, and, when he saw that his precious machinery was not damaged he could view the earth tremors calmly.

"Slight!" exclaimed Mr. Jenks. "Well, I don't call it so. But I see Captain Mentor and Mr. Hosbrook coming. Please don't say anything to them about the diamonds. I'll see you again," and with that, the queer Mr. Jenks walked away.

"We came to see if you were hurt," called the captain, as he neared the young inventor.

"No, I'm all right. How about the others?"

"Only frightened," replied the yacht owner. "This is getting awful.

I hoped we were free from the shocks, but they still continue."

"And I guess they will," added Tom. "We certainly are on Earthquake Island!"

"Mr. Parker, the scientist, says this last shock bears out his theory," went on the millionaire. "He says it will be only a question of a few days when the whole island will disappear."

"Comforting, to say the least," commented Tom.

"I should say so. But what are you doing, Mr. Swift?"

"Trying an experiment," answered the young inventor, in some confusion. He was not yet ready to talk about his plans.

"We must begin to think seriously of building some sort of a boat or raft, and getting away from the island," went on the millionaire.

"It will be perilous to go to sea with anything we can construct, but it is risking our lives to stay here. I don't know what to do."

"Perhaps Captain Mentor has some plan," suggested Tom, hoping to change the subject.

"No," answered the commander, "I confess I am at a loss to know what to do. There is nothing with which to do anything, that is the trouble! But I did think of hoisting another signal, on this end of the island, where it might be seen if our first one wasn't. I believe I'll do that," and he moved away, to carry out his intention.

"Well, I think I'll get back, Tom, and tell the others that you are all right," spoke Mr. Hosbrook. "I left the camp, after the shock, because Mrs. Nestor was worried about you." The place to which the airship machinery had been removed was some distance from the camp, and out of sight of the shacks.

"Oh, yes. I'm all right," said Tom. Then, with a sudden impulse, he asked: