g bomb explosions was his daily exercise before
breakfast.

Tom and Mr. Titus introduced themselves by name.

"I am Professor Swyington Bumper," said the bomb-holder, with a bow,
removing his hat, and again disclosing his shiny bald head. "I am very
glad to have met you indeed."

"And we are more than glad," said Tom, fervently, as he glanced at the
explosive.

"Now that the danger is over," went on Mr. Titus, "suppose we make an
investigation, and find out how this bomb came to be here."

"Just what I was about to suggest," remarked Professor Bumper. "Bombs,
such as this, do not sprout of themselves on bare decks. And I take it
this one is explosive."

"Let me look at it," suggested Tom. "I know something of explosives."

It needed but a casual examination on the part of one who had done
considerable experimenting with explosives to disclose the fact that it
had every characteristic of a dangerous bomb. Only the pulling out of
the fuse had rendered it harmless.

"If it had gone off," said Tom, "we would both have been killed, or, at
least, badly injured, Mr. Titus."

"I believe you, Tom. And we owe our lives to Professor Bumper."

"I'm glad I could be of service, gentlemen," the scientist remarked, in
an easy tone. "Explosives are out of my line, but I guessed it was
rather dangerous to let this go off. Have you any idea how it got
here?"

"Not in the least," said Tom. "But some one must have placed it here,
or dropped it behind us."

"Would any one have an object in doing such a thing?" the professor
asked.

Tom and Mr. Titus looked at one another.

"Waddington!" murmured the contractor. "If he were on board I should
say he might have done it to get us out of the way, though I would not
go so far as to say he meant to kill us. It may be this bomb has only a
light charge in it, and he only meant to cripple us."

"We'll find out about that," said Tom. "I'll open it."

"Better be careful," urged Mr. Titus.

"I will," the young inventor promised. "I beg your pardon," he went on
to Professor Bumper. "We have been talking about something of which you
know nothing. Briefly, there is a certain man who is trying to
interfere in some work in which Mr. Titus and I are interested, and we
think, if he were on board, he might have placed this bomb where it
would injure us."

"Is he here?" asked the professor.

"No. And that is what makes it all the more strange," said Mr. Titus.
"At one time I thought he