BOB PURSUES!

Realizing that the watchman did not know what he meant by “the mystery
crate,” Bob hurriedly told of the earlier experiences: all the while he
talked his mind was busy, underneath, wondering why the pilot of the
brown ship had flown over the plant, why he had appeared to lose control
when the light flared up, why he had climbed to get away.

“He’s gone!” said the watchman. “Anyhow, that’s clear!”

“I hate to see him get away!” Bob said, sorrowfully.

“Whyn’t you chase him?”

“I?” Bob was startled by the idea.

“Sure—you! Didn’t I see Lang giving you lessons, and Griff, too?”

“Yes—but, at night—and Lang has the small ship.”

The watchman seemed to have caught the excitement of a chase.

“Look here, though!” he cried, beckoning as he ran. “In the hangar is a
crate just like Griff’s model—belonged to Mr. Tredway. He—he won’t need
it no more. Whyn’t you?——”

“At night?”

“Sure! Once you get off the ground, the air’s all the same, day or
night, ain’t it?”

Not exactly, Bob demurred, There were many considerations to be thought
out, but his father had said “locate the brown ship.”

Here it was, flying away!

It seemed to be “up to him.”

“Can we get the crate out? Can we get it started? Is there any fuel
aboard?”

Already the watchman had hold of the tail assembly of a trim, slender,
dark fuselage.

“Grab on!” answered the watchman, jockeying the fuselage so that a
wingtip missed the span of the cabin ‘plane’s spreading airfoils. “Grab
on! I know you lads is detectiffs, and here’s your chance for a medal or
somethin’.”

Bob “grabbed on!” with spirit. He had caught the enthusiasm of the older
person. It took them only a short time to jockey the craft into the
open, to get its gauges checked, to see that it had oil and at least a
tank of gas three-quarters full.

“Holler out!” The watchman stood by the “prop.”

“Ready!”

“Gas on?”

“Gas on!”

“Switch off?”

“Switch off!”

The watchman spun the propeller.

“Contact!” he yelled, stepping swiftly beyond the range of those deadly
sharp blade tips.

There came the snap and bark of the motor. Cold! But Bob, feeling that
for all the precious seconds it must waste, he ought to be safe before
he might be sorry, allowed it to warm up, checked his instruments as he
had observed Lang and Griff do, and then, as the watchman, obeying his
signal, kicked away the chocks so the wheels could move forward, the
amateur pilot, steady and cool all at once, glanced at the windsock, saw
that he could take off straight down the short field, pulled open the
throttle, tipped the “flippers” so the tail ceased to drag, as the
propeller blast caught the elevators, and began to race down the field.

As he went he tipped the elevators sharply, felt the ship sway a trifle,
realized he was off the ground and moving steadily, climbing to the roar
of the engine!

He smiled a little. He had not forgotten to hold the ship level for the
brief seconds that it needed to assume flying speed after the first hop
from earth. He had not climbed her at too steep an angle, there was no
indication, at least to his inexperienced hand, of any logginess of the
controls presaging a stall. He was away!

“Now,” he thought, with a sharp glance around the sky spaces, “I am in
for it. If nothing goes wrong with the machinery or the prop I guess I
can keep this crate level and get somewhere.”

But where?

In those precious moments the brown ship could have gone ten miles.

“He was mightily interested in the aircraft plant,” Bob reflected,
letting the ship “fly herself,” as most well balanced aircraft will do
in steady air, as long as flying speed is held. “Now all that we have
found out, so far, has centered about the aircraft plant and—and The
Windsock! Could he be around there? Or——”

As a new thought struck him he gripped the stick a tiny bit tighter.

“—Or, maybe he’s brought the brown ship back for some new stunt! It
might be hidden in that field again!”

He pushed the stick a trifle to the side, thus operating the ailerons,
while he used his rudder experimentally, meaning to swing in a circle.

Whether a good Providence watches over amateurs, in sports or in
professions, or whether Bob had actually learned from his lessons, the
fact is that he did not overbank or use too much rudder, and neither
felt the wind of a skid on one cheek nor the breeze of a slip on the
other. Around went the ship, in a wide swing.

Bob kept his eyes on the sky, with momentary glances at the instruments,
not all of which were understandable to him yet; however, he knew the
altimeter, the tachometer which records engine speed, the gas and oil
pressure gauges and such important ones.

They seemed all to record satisfactorily. His altitude was six hundred
feet; a little low for safety, so he climbed to twice that. The
revolutions were even and plenty for his need, as he watched the
fluctuations of the tachometer when he eased the throttle forward in his
climb, or backed it gently in the level-off.

Gas and oil recorded without a hitch or a diminution of supply.

But where was his quarry?

Far ahead Bob saw a tiny flare of red in the sky.

He nearly lost control in his excitement, but with the true air-sense he
caught the tendency of the sideslip by opposite rudder and aileron and
then banked and circled till his nose pointed straight for the dying
flare.

Someone in the sky was signaling for something!

“I’ll get there soon! And see!” Bob told himself. He held the ship
level, glancing at the “bubble” in the spirit level, as he gave the gun,
opening the throttle steadily.

To the roar of the engine, the sing of cool wind in taut wires, the
sting of pulsing blood pounding a thrill-song in his temples, Bob took
up his quest, and soon saw, ahead, the dim outline of a circling ship.
It was dark. Was it brown?

He dared not get too close. Rather, he preferred to climb, so as to be
safely out of the other fellow’s way if he maneuvered.

From above Bob planned to light a white flare, by whose light he could
identify the ship.

But the other fellow saw him too!

Bob needed no flare to tell him that he had discovered the brown
craft—its action was indication enough! The pilot dived, and then went
into a barrel-roll, dangerous at a low altitude, Bob thought.

The “stunt” enabled the ship to get to one side and out of his line of
flight if he dived for it.

Clearly this showed that the unseen pilot feared to be attacked, driven
down.

But Bob had no such intention, he merely followed as the small, brown
craft, speedy and capable, went fleetly through the night.

Bob, easing his throttle a little more open, as he got the line of
flight, held his elevation and his level position; he did not try to
overtake the other, he wanted to see where he went—nothing more!

So the flight held, one about five hundred feet up, the other easily as
high again. The speed was almost identical, the ships were well matched.

But the other man had some tricks up his wings, in a way of speaking!

He began to climb. Bob, fearing to be over-reached, climbed also.
Higher, higher they both went, Bob still atop the other, for he had as
much power, as well angled wings, as clever a ship as his adversary.

But the battle of elevation was short. At fifteen hundred feet the brown
‘plane went into a wingover, and to Bob’s dismay it was, by that
maneuver, in a reverse direction to the flight of his own, and he dared
do no maneuvering, no stunting, at night and alone!

Before he could swing in the easy circle which his inexperience
compelled him to use, the other pilot was almost out of sight. He
climbed, and thus Bob gained, but he saw that his pursuit was futile.

The man was climbing into a cloud!

In its misty vastness, surrounding a ship like a fog, an inexpert pilot
could not know, without continually watching his spirit level and other
instruments, if he flew level or on his back, if he was going sidewise
or straight toward earth. To watch the instruments “to fly by the
dashboard” was useless; he could not see to follow if he risked the
feat.

Disgusted, disappointed, he cut the gun and slowed his ship, and flew
around toward The Windsock. Somebody on the ground was burning several
land flares, he saw.

It told him one thing! The other fellow had been expected! His signal
had been seen.

For an instant Bob was tempted to try a landing, to see if they would be
startled, those people down there in the glare. Did they perhaps think
he flew the craft they expected? It would be worth something to discover
that. Or—would it? The danger, the risk, was considerable. It was
strange territory to him. The people, seeing his craft markings, its
different color, might extinguish the flares, leaving him, low, to “set
down hot” or to climb, too late, and land in trees!

No, it was not worth the risk.

If his adversary had gotten away that was the end of the adventure.

Only—it wasn’t.