"How
high now?"

"About fifteen hundred feet," guessed Tom.

"Wrong," said Jack, glancing at the barograph on the dashboard in
front of him. "We have reached two thousand eight hundred feet."

"I must be asleep," said Tom, frowning. "Shall I connect the
alternator?"

Jack nodded and prepared to send greetings to his father, hundreds of
miles away. They were out in the country now. As the Wondership glided
through the air, the professor, in viewing the villages, farms, green
pastures, and stretches of woodland, regretfully shook his head as the
thought occurred to him that he was missing many a precious stone. He
looked over to Jack with the idea of suggesting a descent, but he saw
the boy inventor patiently adjusting the tuning knob, and waited,
realizing how anxious Jack was to test the Coloradite.

The little professor, extremely interested, saw Jack place his lips to
the receiver, and for the second time in his life, send out the
distinct call:

"Hullo, High Towers!"

Many minutes passed without an answer. Jack's face became grave. Was
part of the machinery not properly adjusted? He went over the
instrument very carefully. In so far as he could see, everything was
just as it should be. Then a thought came that made him dizzy--was it
possible that the Coloradite was not suited for the work, that Mr.
Chadwick had been misinformed?

"What's up?" inquired Tom, glancing up from his engines.

"By the ghost of Guzzlewits!" gasped Dick. "Don't say it won't work,
Jack!"

The professor, ordinarily cool and very calculating, was strangely
stirred. He watched the young inventor's face. Did it mean failure?

"I don't know," said Jack at last with forced calmness. "I will try
again."

Once more Jack, oppressed by a vague fear, sent out the words:

"Hullo, High Towers!"

The reply came with startling swiftness, relieving the party from the
mental strain. In one voice--the professor included--they yelled,

"Hurrah!"

"Congratulations!" came Mr. Chadwick's voice in return.

"Why the delay?" asked Jack, smiling with

"A small lever snapped. It required a few minutes to repair it. How
far from New York are you now?"

"About forty miles."

"Good! Try to land here before sunset."

"Why?" asked Jack.

"Nestorville has a little surprise for you!" replied Mr. Chadwick, and
Jack heard him chuckle.

"Good for Mr. Chadwick!" cried Dick in glee, for Jack had so arranged
the instrument that all of them in the Won