fty miles every sixty
minutes. The captive balloons, and other landmarks, enabled them to
keep to their course.

Dick put his craft through several "stunts" to further test its
reliability and flexibility. To every one she answered perfectly. The
gyroscope stabilizer was particularly effective, and no matter how
severe a strain was put on the craft, she either came to an even keel
at once when deflected from it, or else did not deviate from it.

"I shall certainly report as to the wisdom of having such an apparatus
on every airship the United States uses," declared Lieutenant McBride.
"No matter whether Dick Hamilton's craft wins the prize or not,--and I
certainly hope he does--the gyroscope must be used."

"I am glad to hear you say so," spoke the inventor, "but I never would
have been able to perfect it had it not been for my friend Dick
Hamilton."

"Why don't you blush, Dick?" asked Innis, playfully.

"I don't take any credit to myself at all," said the young millionaire.

"Well, I'm going to give it to you," declared the aviator. "From now
on the gyroscope stabilizer will be known as the Vardon-Hamilton, and
some additional patents I contemplate taking out will be in our joint
names."

"Thanks," said Dick, "but I'll accept only on one condition."

"What is that?"

"It is that no money from this invention comes to me. If I win the
twenty thousand dollar prize I'll be content."

"What are you going to do with the money?" asked Paul Drew, for Dick
really had no need of it.

"I'll build a new gym, at Kentfield," was the reply. "Our present one
is too small. We need an indoor baseball cage too."

"Good for you!" cried Innis. "You're a real sport!"

In the evolutions of the airship each one aboard was given a chance to
pilot her. He was also allowed to stop and start the machinery, since
it could not be told at what moment, in an emergency, someone would
have to jump into the breech.

It was about three o'clock in the afternoon, when Dick's ship was
nearing the Western borders of Pennsylvania, that Paul, who was looking
down through the celluloid floor in the cabin, cried out:

"Something going on down below us, boys!"

All save Innis, who was steering, crowded around the odd window.

"Why, there's an airship meet going on down there," said Dick. "Look,
there are a lot of monoplanes and some biplanes."

"Let's go down a bit and salute them," suggested Larry.

"Down she is!" cried Innis, as