Chapter XVII. A Mighty Shock
 

Tom Swift turned to gaze at Mr. Barcoe Jenks. That individual certainly had a strange manner. Perhaps it might be caused by the terror of the earthquakes, but the man seemed to be trying to hold back some secret. He was constrained and ill at ease. He saw the young inventor looking at him, and his hands, which had gone to his belt, with a spasmodic motion, dropped to his side.

"You don't really mean to say, Parker, that you think the whole island is undermined, do you?" asked the owner of the Resolute.

"That's my theory. It may be a wrong one, but it is borne out by the facts already presented to us. I greatly fear for our lives!"

"But what can we do?" cried Mrs. Nestor.

"Nothing," answered the scientist, with a shrug of his shoulders. "Absolutely nothing, save to wait for it to happen."

"Don't say that!" begged Mrs. Andersen.

"Can't you gentlemen do something--build a boat and take us away. Why, the boat we came here in--"

"Struck a rock, and stove a hole in the bottom as big as a barrel, madam," interrupted Captain Mentor. "It would never do to put to sea in that."

"But can't something else be done?" demanded Mrs. Nestor. "Oh, it is awful to think of perishing on this terrible earthquake island. Oh, Amos! Think of it, and Mary home alone! Have you seen her lately, Mr. Swift?"

Tom told of his visit to the Nestors' home. Our hero was almost in despair, not so much for himself, as for the unfortunate women of the party--and one of them was Mary's mother! Yet what could he do? What chance was there of escaping from the earthquake?

"Bless my gizzard!" exclaimed Mr. Damon. "Don't let's stand here worrying! If you folks are hungry come up to our camp. We have plenty. Afterward we can discuss means of saving ourselves."

"I want to be saved!" exclaimed Mr. Jenks. "I must be saved! I have a great secret--a secret--"

Once more he paused in confusion, and once more his hands nervously sought his belt.

"I would give a big reward to be saved," he murmured.

"And so, I fancy, we all would," added Captain Mentor. "But we are not likely to. This island is out of the track of the regular line of vessels."

"Where are we, anyhow?" inquired Mr. Fenwick. "What island is this?"

"It isn't down on the charts, I believe," was the captain's reply, "but we won't be far out, if we call it Earthquake Island. That name seems to fit it exactly."

They had walked on, while talking, and now had gone past the broken cliff. Tom and his two friends of the airship led the way to the camp they had made. On the way, Mr. Hosbrook related how his yacht had struggled in vain against the tempest, how she had sprung a leak, how the fires had gone out, and how, helpless in the trough of the sea, the gallant vessel began to founder. Then they had taken to the boats, and had, most unexpectedly come upon the island.

"And since we landed we have had very little to eat," said Mrs. Nestor. "We haven't had a place to sleep, and it has been terrible. Then, too, the earthquakes! And my husband and I worried so about Mary. Oh, Mr. Swift! Do you think there is any chance of us ever seeing her again?"

"I don't know," answered Tom, softly. "I'll do all I can to get us off this island. Perhaps we can build a raft, and set out. If we stay here there is no telling what will happen, if that scientist's theory is correct. But there is our camp, just ahead. You will be more comfortable, at least for a little while."

In a short time they were at the place where Tom and the others had built the shack. The ruins of the airship were examined with interest, and the two women took advantage of the seclusion of the little hut, to get some much needed rest until a meal should be ready.

One was soon in course of preparation by Tom and Mr. Damon, aided by Mate Fordam, of the Resolute. Fortunate it was that Mr. Fenwick had brought along such a supply of food, for there were now many mouths to feed.

That the supper (which the meal really was, for it was getting late) was much enjoyed, goes without saying. The yacht castaways had subsisted on what little food had been hurriedly put into the life boat, as they left the vessel.

At Tom's request, while it was yet light, Captain Mentor and some of the men hunted for a spring of fresh water, and found one, for, with the increase in the party, the young inventor saw the necessity for more water. The spring gave promise of supplying a sufficient quantity.

There was plenty of material at hand for making other shacks, and they were soon in course of construction. They were made light, as was the one Tom and his friends first built, so that, in case of another shock, no one would be hurt seriously. The two ladies were given the larger shack, and the men divided themselves between two others that were hastily erected on the beach. The remainder of the food and stores was taken from the wreck of the airship, and when darkness began to fall, the camp was snug and comfortable, a big fire of driftwood burning brightly.

"Oh, if only we can sleep without being awakened by an earthquake!" exclaimed Mrs. Nestor, as she prepared to go into the shack with Mrs. Anderson. "But I am almost afraid to close my eyes!"

"If it would do any good to stay up and watch, to tell you when one was coming, I'd do so," spoke Tom, with a laugh, "but they come without warning."

However, the night did pass peacefully, and there was not the least tremor of the island. In the morning the castaways took courage and, after breakfast, began discussing their situation more calmly.

"It seems to me that the only solution is to build some sort of a raft, or other craft and leave the island," said Mr. Fenwick.

"Bless my hair brush!" cried Mr. Damon. "Why can't we hoist a signal of distress, and wait for some steamer to see it and call for us? It seems to me that would be more simple than going to sea on a raft. I don't like the idea."

"A signal would be all right, if this island was in the path of the steamers," said Captain Mentor. "But it isn't. Our flag might fly for a year, and never be seen."

His words seemed to strike coldness to every heart. Tom, who was looking at the wreck of the airship, suddenly uttered an exclamation. He sprang to his reet

"What is it?" demanded Mr. Fenwick. "Does your sore leg hurt you?"

"No, but I have just thought of a plan!" fairly shouted the young inventor. "I have it! Wait and see if I can work it!"

"Work what?" cried Mr. Damon.

Tom did not get a chance to answer, for, at that moment, there sounded, at the far end of the island, whence the yacht castaways had come, a terrific crash. It was accompanied, rather than followed, by a shaking, trembling and swaying of the ground.

"Another earthquake!" screamed Mrs. Nestor, rushing toward her husband. The castaways gazed at each other affrighted.

Suddenly, before their eyes, they saw the extreme end of that part of the island on which they were camping, slip off, and beneath the foaming waves of the sea, while the echoes of the mighty crash came to their ears!