“I shouldn’t like to be as high as that,” remarked Ned.

“I would,” answered Tom as he slowed down the engine the better to watch the balloon.  “I’d like to go up in an airship, and I intend to some day.”

“I believe he’s going to jump!” suddenly exclaimed Ned after a few minutes.  “He’s going to do something, anyhow.”

“Probably come down in a parachute,” said Tom.  “They generally do that.”

“No!  No!” cried Ned.  “He isn’t going to jump.  Something has happened!  The balloon is on fire!  He’ll be burned to death!”

Horror stricken, they all gazed aloft.  From the mouth of the balloon there shot a tongue of fire, and it was followed by a cloud of black smoke.  The big bag was getting smaller and seemed to be descending, while the man on the trapeze was hanging downward by his hands to get as far as possible away from the terrible heat.

CHAPTER XXII

THE RESCUE

“Jump!  Jump!” cried Mr. Swift, leaping to his feet and motioning to the man on the trapeze of the balloon.  But it is doubtful whether or not the performer heard him.  Certainly he could not see the frantic motions of the inventor.  “Why doesn’t he jump?” Mr. Swift went on piteously to the two lads.  “He’ll surely be burned to death if he hangs on there!”

“It’s too far to leap!” exclaimed Tom.  “He’s a good way up in the air, though it looks like only a short distance.  He would be killed if he dropped now.”

“He ought to have a parachute,” added Ned.  “Most of those men do when they go up in a balloon.  Why doesn’t he come down in that?  I wonder how the balloon took fire?”

“Maybe he hasn’t a parachute,” suggested Tom, while he slowed down the motor-boat still more so as to remain very nearly under the blazing balloon.

“Yes, he has!” cried Ned.  “See, it’s hanging to one side of the big bag.  He ought to cut loose.  He could save himself then.  Why doesn’t he?”

The balloon was slowly twisting about, gradually settling to the surface of the lake, but all the while the flames were becoming fiercer and the black clouds of smoke increased in size.

“There, see the parachute!” went on Ned.

The twisting of the bag had brought into view the parachute or big, umbrella-shaped bag, which would have enabled the man to safely drop to the surface of the lake.  Without it he would have hit the water with such force that he would have been killed as surely as if he had struck the solid earth.  But the boys and Mr. Swift also saw something else, and this was that the balloon was on fire on the same side where the parachute was suspended.

“Look!  Look!” shouted Tom, bringing his boat to a stop.  “That’s why he can’t jump!  He can’t reach the parachute!”