"Oh, I won't say that I can explain it, for I do not pretend to understand it; but I'll wager that the mystery would be readily solved if we could overtake and examine that canoe."

"Mebbe so; but I think it nades a stameboat to overtake it."

Professor Scotch shook his head in a most solemn manner.

"Boys," he said, "in all my career I have never seen anything like this, and I shall never dare tell this adventure, for people in general would not believe it--they'd think I was lying."

"Without doubt," admitted Frank. "And, still I will wager that the explanation of the whole matter would seem very simple if we could overtake that canoe and examine it."

"Perhaps so."

"You speak as if you doubted it."

"Possibly I do."

"I am surprised at you, professor--I am more than surprised."

"I can't help it if you are, my boy."

"I am afraid your mind is beginning to weaken."

"Soay, Frankie," broke in Barney. "Oi loike fun as well as th' nixt wan, but, be jabbers! it's nivver a bit av it can Oi see in this!"

"See that infernal canoe?" cried the professor, pointing at the mystic craft. "It has stopped out there in the shadows."

"And seems to be waiting for us to pursue again."

"That's what it's doing."

"I'm ready!" exclaimed Frank.

"I am not," decisively declared Professor Scotch.

"Nayther am Oi!" almost shouted the Irish youth. "It's enough av this koind av business Oi've been in!"

"We'll turn about," said Scotch, grimly. "That canoe will lure us into this dismal swamp so far that we'll never find our way out. We'll turn about at once."

Frank laughed.

"All right," he said. "I suppose I'll have to give up, but I do dislike to leave without solving the mystery of that canoe."

"It may be thot we're so far in thot we can't foind our way out at all, at all," said the Irish lad.

"I'm afraid we'll not be able to get out before nightfall," confessed the professor. "I have no fancy for spending a night in this swamp."

Barney promptly expressed his dislike for such an adventure, but Frank was silent.

The canoe turned about, and they set about the task of retracing the water courses by which they had come far into the swamp.

It was not long before they came to a place where the courses divided.

Frank was for following one, while both Barney and the professor insisted that the other was the right way.

Finally, Frank gave in to them, although it was against his better judgment, and he felt that he should not submit.

They had not proceeded far before, as they were pa.s.sing round a bend, a cry of astonishment fell from Barney's lips.

"Howly shmoke!" he shouted. "Thot bates th' band!"

"What's the matter?" asked Frank and the professor, together.

"Thot whoite canoe!"

"What of it?"

"Look back! Th' thing is afther follying av us!"

They looked back, and, sure enough, there was the mysterious canoe, gliding after them, like a most uncanny thing!

"Well, I like that!" said Frank, in a tone that plainly indicated he did not like it. "This is very pleasant!"

"Pull, pull!" throbbed the professor, splashing his paddle into the water and very nearly upsetting them all. "Don't let the thing overtake us! Pull, pull!"

"Oi think it's a foine plan to be gettin' out av this," muttered Barney, in an agitated tone of voice.

"Steady, there, professor," called Frank, sharply. "What do you want to do--drown us all? Keep cool."

"It's coming!" fluttered the little man, wildly.

"Let it come. As long as we could not overtake it, let it overtake us.

That is a very good scheme."

"Th' skame won't worruck, me b'y. Th' ould thing's shtopped."

It was true; the white canoe had stopped, and was lying calmly on the inky surface of the shadowed water.

"Well, I can't say that I like this," said Frank.

"And I scarcely think I like it more than you do," came from the professor.

"An' th' both av yez loike it as well as mesilf," put in the Irish youth.

"What are we to do?"

"Go on."

Go on they did, but the white canoe still followed, keeping at a distance.

"I can't stand this," declared Frank, as he picked up a rifle from the bottom of the canoe. "I wonder how lead will work on her?"