Leo's first care, after leaving the hospital, was to ask about Mart.
He was astonished to learn at the hotel at which the party was stopping
that nothing had been seen of the lad since the balloon had left the
exhibition grounds.
Greson had gone for the balloon late the day before.
"Found the balloon all right, but didn't see a single trace of the boy,"
said the assistant.
"That is queer," mused Leo. "Can it be that he tumbled down in some
out-of-the-way place and was killed?"
He at once learned the course the balloon had taken, and then got a
buggy and horse and went over every inch of the ground.
A little later he found himself at the spot where the balloon had come
down.
He walked around in much perplexity.
If Mart had escaped injury, where was he?
"All this must be Porler's work," said the young gymnast to himself. "I
would just like to come across that man."
Satisfied that nothing was to be gained by remaining near the woods, Leo
started back to the road.
In doing this he came across the bottle which had contained the
chloroform Porler had used.
He picked up the bottle and smelled of what remained in it.
"My gracious!"
Like a flash the truth burst upon him.
"It's that rascal's work! He fired on me, and then came out here after
Mart. He has abducted the boy!"
As we know, Leo was partly right and partly wrong.
The young gymnast realized that if he was to act he must do so without
delay.
It made him very angry to think of the young lad being in the old
balloonist's power.
That he would ill-use Mart he felt certain.
From where he had found the bottle Leo traced Porler's footsteps to the
carriage.
The marks of the carriage wheels were still fresh and they ran straight
into the city.
On the pavements they were, of course, lost.
Leo was in a quandary.
He told Greson of what he had discovered, and then both of them began a
systematic search for Mart.
Greson started from where the carriage had entered the city.
The young gymnast went to the exhibition grounds and attempted to trace
up the man who had fired the shots at the balloon.
From one and another the young gymnast was able to trace up Porler to a
third-rate boarding-house on one of the side streets.
He was about to enter the place when he saw a fellow named Danny Murphy,
who was Porler's assistant, leaving in a great hurry.
"Perhaps he is going to join Porler at some place where Mart is being
kept," said Leo to himself. "I'll follow him."
And follow Murphy he did.
All unconscious of being watched, Porler's tool walked half a dozen
blocks until he came to the residence in which Mart was kept a close
prisoner. He walked around to the rear through an alleyway.
Close behind him, Leo heard him give a peculiar knock on the door.
A moment passed and Murphy was admitted. The back door was locked and
bolted after him.
When the door had been opened Leo had caught a momentary glimpse of
Porler's face.
"That settles it," he thought. "Mart is kept a prisoner right here."
Leo had armed himself, and now he walked to one of the kitchen windows.
He opened the blinds. The window itself was locked, but bringing out his
pocketknife he shoved back the catch.
Another moment and the lower sash was raised and the young gymnast
leaped into the house.
He did not care if his enemies were present. He was prepared to fight,
if need be.
But, as he surmised, the lower floor of the residence was deserted.
With cautious steps Leo left the kitchen and walked toward the stairs
leading to the next floor.
As he did so he heard the murmur of voices from above.
He went up and listened with strained ears.
"Mr. Porler, starve me or not, I will never do as you wish."
It was Mart who was speaking.
"And I say you will do so," growled Porler.
"That's right," put in Murphy. "Make the boy toe the mark."
"I will not only starve you," went on Porler, "but I will give you a
taste of your old friend, the strap."
"You will not dare to touch me!" exclaimed the lad.
"Wait and see."
"My friend, Mr. Dunbar, will have the law on you for it."
"Dunbar will never help you again."
"I think he will."
The voice came from the doorway, and the three in the room found
themselves confronted by Leo.