reimbursing us," went on Mr. Fenwick, with rather a
suspicious glance at Mr. Jenks. "You are welcome to whatever we
have."

"Bless my topknot; certainly, yes!" joined in Mr. Damon, eagerly.

"Well, I--er--I only spoke of it," said Mr. Jenks, hesitatingly, and
then he turned away. Mr. Hosbrook looked sharply at him, but said
nothing.

"Suppose we go to our camp," proposed Tom. "We may be able to get
you up a good meal, before another earthquake comes."

"I wonder what makes so many of them?" asked Mrs. Nestor, with a
nervous shiver.

"Yes, indeed, they are terrifying! One never knows when to expect
them," added Mrs. Anderson.

"I have a theory about them," said Mr. Parker, the scientist, who,
up to this time had spoken but little.

"A theory?" inquired Tom.

"Yes. This island is one of the smaller of the West Indies group. It
is little known, and has seldom been visited, I believe. But I am
sure that what causes the earthquakes is that the whole island has
been undermined by the sea, and it is the wash of great submarine
waves and currents which cause the tremors."

"Undermined by the sea?" repeated Tom.

"Yes. It is being slowly washed away."

"Bless my soul! Washed away!" gasped Mr. Damon.

"And, in the course of a comparatively short time, it will sink,"
went on the scientist, as cheerfully as though he was a professor
propounding some problem to his class.

"Sink!" ejaculated Mrs. Nestor. "The whole island undermined! Oh,
what an alarming theory!"

"I wish I could hold to a different one, madam," was Mr. Parker's
answer, "but I cannot. I think the island will sink after a few more
shocks."

"Then what good will my--" began Barcoe Jenks, but he stopped in
confusion, and again his hand went to his belt with a queer gesture.

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!"