g up and down the road, he heard from afar, a
peculiar humming sound. He paused to listen.

"Trolley car," observed Mr. Sharp. "Maybe one of us could go somewhere
on the trolley and get help. There it is," and he pointed to the
electric vehicle, moving along about half a mile away, at the foot of a
gentle slope.

At the sight of the car Tom uttered a cry. "I have it!" he exclaimed.
"None of us need go for help! It's right at hand!" His companions
looked curiously, as the young inventor pointed triumphantly to the
fast disappearing electric.

CHAPTER XXIV

ON THE TRACK

"What do you mean?" asked Mr. Damon. "Will the electric trolley pull us
to a charging station?"

"No, we'll not need to go to a station," answered the youth. "If we
can get my car to the trolley tracks I can charge my battery from
there. And I think we can push the auto near enough. It's down hill,
and I've got a long wire so we won't have to go too close."

"Good!" cried Mr. Sharp. "But attach the rope to the front of the car,
Tom. Mr. Damon and I will pull it. You'll have to ride in it to steer
it."

"We can take turns at riding," was Tom's answer, for he did not want
his companions to do all the work.

"Nonsense! You ride," said Mr. Damon. "You're lighter than we are, and
can steer better. It won't be any trouble at all to pull this car down
hill."

It proved to be an easy task, and in a short time the "dead" auto was
near enough to the electric line to permit Tom to run his charging wire
over to it.

"Why bless my soul!" exclaimed Mr. Damon, looking up. "There's no
overhead trolley wire. The car must run on storage batteries."

"Third rail, more likely," was the opinion of Mr. Sharp and so it
proved.

"I can charge from either the third rail or the trolley wire," declared
Tom, who was insulating his hands in rubber gloves, and getting his
wires ready. In a short time he had the proper connections made, and
the much-needed current was soon flowing into the depleted battery, or
batteries, for there were several sets, though the whole source of
motive power was usually referred to as a "storage battery."

"How long will it take?" asked Mr. Damon.

"About two hours," answered the lad. "We'll probably have to disconnect
our wires several times, whenever a trolley car comes past. By my
system I can recharge the battery very quickly.

"Do you suppose the owners of the road will make any objection?" asked
the balloonist.

"I