er for
several minutes.

"Fargo's is the place to go to," said Shocker, presently. "I know we can
trust him."

"Of course, I don't want to hurt Porter," said Nat, nervously. "I only
want to scare him."

"Sure, I understand. We'll scare the wits out of him," returned Tom
Shocker. "Now, let me see. I have it--we'll catch him on the bridge. His
carriage is bound to come that way, to get off Goat Island."

Dave and his friends spent the best part of a quarter of an hour around
the Three Sisters Islands and then returned to their carriage.

"Now we can go to the hotel and have dinner," said Dunston Porter. "And
then we can take a local train back to Buffalo."

The carriage was just crossing the bridge that connects Goat Island with
the city of Niagara Falls when a man stepped up and stopped the turnout.
It was Tom Shocker.

"Excuse me, but I reckon this is the number, 176," he said. "Is there a
young man here named David Porter?"

"Yes, I am Dave Porter," answered Dave, and looked at Shocker curiously.
The fellow was a total stranger to him.

"Got a note for you," went on Shocker, and produced it. It was sealed
and marked _Private_ in plain letters.

Wondering what the note could contain, Dave opened and read it. His face
changed color and he gave a little gasp.

"Excuse me, I'll have to--to leave you for a little while," he stammered
to the others.

"What's the matter?" asked Roger.

"I--I can't tell you just now." Dave turned to his uncle. "Where will
you get dinner, Uncle Dunston?"

"At the International."

"All right--I'll be there before long," answered Dave, and sprang to the
ground.

"But what's up?" cried Phil. He could see that his chum was much
disturbed.

"I--I can't tell you, Phil. But I'll be back before you finish your
dinner."

"Don't you want some one along?" asked Laura, who did not like to see
her brother depart in the company of such a looking stranger as Tom
Shocker.

"No, Laura. Oh, it's all right. I'll be at the International on time,"
said Dave, and then he hurried over the bridge and down a side street of
the city, in company with Tom Shocker.

The note Dave had received was written in a cramped hand and ran as
follows:

"DEAR DAVE:--You will be surprised to receive this, but I saw you
in town to-day and noted the number of your carriage. I am in deep
trouble and would like you to come and see me in private, if only
for five or ten minutes. You can ai