Fairly fascinated by the spluttering fuse, neither Tom nor Mr. Titus moved for a second, while the deadly fire crept on through the black string-like affair, nearer and nearer to the bomb itself.

Then, just as Tom, holding back his natural fear, was about to thrust the thing overboard with his foot, hardly realizing that it might be even more deadly to the ship in the water than it was on the deck, the foot of the newcomer was suddenly thrust out from behind the deck-house, and the sizzling fuse was trodden upon.

It went out in a puff of smoke, but the owner of the foot was not satisfied with that for a hand reached down, lifted the bomb, the fuse of which still showed a smouldering spark of fire, and calmly pulled out the "tail" of the explosive. It was harmless then, for the fuse, with a trail of smoke following, was tossed into the sea, and the little man came out from behind the deck-house, holding the unexploded bomb.

For a moment neither Tom nor Mr. Titus could speak. They felt an inexpressible sense of relief. Then Tom managed to gasp out:

"You--you saved our lives!"

The little man who had stepped on the fuse, and had then torn it from the bomb, looked at the object in his hand as though it were the most natural thing in the world to pick explosives up off the deck of passenger steamers, as he remarked:

"Well, perhaps I did. Yes, I think it would have gone off in another second or two. Rather curious; isn't it?"

"Curious? Curious!" asked and exclaimed Mr. Titus.

"Why, yes," went on the little man, in the most matter of fact tone. "You see, most explosive bombs are round, made that way so the force will be equal in all directions. But this one, you notice, has a bulge, or protuberance, on one side, so to speak. Very curious!

"It might have been made that way to prevent its rolling overboard, or the bomb's walls might be weaker near that bulge to make sure that the force of the explosion would be in that direction. And the bulge was pointed toward you gentlemen, if you noticed."

"I should say I did!" cried Mr. Titus. "My dear sir, you have put us under a heavy debt to you! You saved our lives! I--I am in no frame of mind to thank you now, but--"

He strode over to the little man, holding out his hand.

"No, no, I'd better keep it," went on the person who had rendered the bomb ineffective. "You might drop it you know. You are nervous--your hand shakes."

"I want to shake hands with you!" exclaimed Mr. Titus-- "to thank you!"

"Oh, that's it. I thought you wanted the bomb. Shake hands? Certainly!"

And while this ceremony was being gone through with, Tom had a moment to study the appearance of the man who had saved their lives. He had seen the passenger once or twice before, but had taken no special notice of him. Now he had good reason to observe him.

Tom beheld a little, thin man, little in the sense of being of the "bean pole" construction. His head was as bald as a billiard ball, as the young inventor could notice when the stranger took off his hat to bow formally in response to the greeting of some ladies who passed, while Mr. Titus was shaking hands with him.

The bald head was sunk down between two high shoulders, and when the owner wished to observe anything closely, as he was now observing the bomb, the head was thrust forward somewhat as an eagle might do. And Tom noticed that the eyes of the little man were as bright as those of an eagle. Nothing seemed to escape them.

"I want to add my thanks to those of Mr. Titus for saving our lives," said Tom, as he advanced. "We don't know what to make of it all, but you certainly stopped that bomb from going off."

"Yes, perhaps I did," admitted the little man coolly and calmly, as though preventing 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 was here, but I was mistaken."

Tom took the now harmless bomb to his stateroom, and there, after taking the infernal machine apart, he discovered that it was not as dangerous as he had at first believed.

The bomb contained no missiles, and though it held a quantity of explosive, it was of a slow burning kind. Had it gone off it would have sent out a sheet of flame that would have severely burned him and Mr. Titus, but unless complications had set in death would not have resulted.

"They just wanted to disable us," said the contractor. "That was their game. Tom, who did it?"

"I don't know. Did you ever see this Professor Bumper before?"

"I never did."

"And did it strike you as curious that he should happen to be so near at hand when the bomb fell behind us?"

"I hadn't thought of that," admitted the contractor. "Do you mean that he might have dropped it himself?"

"Well, I wouldn't go so far as to say that," replied Tom, slowly. "But I think it would be a good idea to find out all we can of Professor Swyington Bumper."

"I agree with you, Tom. We'll investigate him."