Alan E. Nourse (14 page)

It
slipped and slid, jouncing him out of the seat time after time, banging his
head on the top, throwing him almost over on his face. It was speed now that
counted, speed more than anything else, and he urged the car forward
recklessly. A dismal red line was forming on the horizon; dawn was not far
away, but the light only confused the picture before him as the half-track
hurtled up the grade and over the rim, leaving the Earth ship far behind. Tuck
hung on for dear life, praying that the machine would stay
upright,
and not run into any of the treacherous gullies and crevices that lay on either
side.

The
Snooper
was in working order. If he could get to the
colony and get David, they could go for the little ship. He had no more idea
than the man in the moon what they would be looking for—but
something
existed, the Big Secret was
somewhere—
and if it existed, it could be found—

A
squeal of jet engines cut through to his ears, and he braked down the
half-track, staring. Like a streak, he saw the little jet swoop down over him,
arc up high, and loop over to come in again. Tuck's heart skipped a beat. David
had had the same idea! He slowed the 'track to a stop, threw open the hood, and
crawled out, running down the grade to the place where the
Snooper
had jetted in.

David
waved, and moved aside in the cockpit, motioning Tuck in beside him. "I
thought I was going to have to storm the ship single-handed to get you
out," he exclaimed. "Your dad really fixed things! I had to sneak
out—sent the air-lock guard on a wild-goose chase and copped his half-track to
get out to the
Snooper—"

"But
why?"

"I've been thinking, Dad got control of
things in the meeting finally—but only because of the fight with the
Colonel." He grinned. "
Cortell's
boys were
having trouble explaining why they would be fighting if they were really in
cahoots. But there's only one thing that will bring any sort of solution
now." He looked up at Tuck, his face eager. "It means selling out my
dad and the colony, but it's the only thing."

"You mean the
plan," Tuck said eagerly.

"Exactly.
Wherever it is, we've got to find it, and
spring it wide-open to everybody. If that won't get dad and the Colonel
together, nothing will."

Tuck
nodded. "It will. It can't help but do it. But where do we start?"

David
chewed his lip for a moment. "Wherever it is, it's connected with the
colony," he said. "I mean by tunnel. I don't have any idea where. The
easiest thing would be to go in through the colony, but I'm afraid that's out.
Cortell
would have the tunnel guarded, whichever one it
was—"

Tuck
blinked. "That would tip us off to the right one—"

"If we ever did find it.
But there may be another way in."

"From
the outside?"

"Right.
If it's a vault, or a battle station,
it's
big-it would have to be to take five hundred people.
There are lots of abandoned shafts that might let us in to the mines. And once
inside, we'll have to make use of every break we can." He snapped on the
primer switch of the jet. "Hang on, boy," he said softly. "We've
got a lot of hunting to do, and we haven't got much time."

Tuck
sat back, hardly able to breathe, the excited whine of the engines driving all thoughts
out of his mind. The little scooter jerked, bumped a time or two, and then
suddenly they were swooping out into the clear, thin atmosphere, rising higher
and higher, until they could see the edge of the morning sun. Time was passing
even now, precious minutes that could mean success or failure. With time
closing in on them, it seemed an almost impossible chance-But somewhere below
them the planet held a secret, a secret that had been kept inviolate for a
hundred years. And in a few short hours, somehow, the secret had to be found—

The Secret
of
the Tunnel

the
quest
seemed
hopeless from the start. Tuck had
I
never
been higher above the surface of Titan than
I
the observation room of the Earth ship; he had * never realized the
vastness of the place. But now, as the
Snooper
skimmed
higher and higher into the sun the realization drove home, and he stared
bleakly down at the wild panorama spread out beneath them.

There
was no break in the barren wildness. A few miles to the right he could see the
oval dome of the colony, reflecting the early morning light, gleaming like a
dull jewel as the lights within it blinked off one by one. But the colony lay
totally isolated by miles and miles of endless rock. Even as they rose, the surface
lost its detail and took on a different sort of wildness. It was a mammoth
chunk of barren rock—

And
somewhere down there five hundred people had carved out a tiny foothold, and
from it were threatening the entire Solar System!

David
Torm
glanced down for an instant.
"Not
very pretty, eh?"

"It
looks horrible. I don t see how we could ever find anything."

David chuckled. "Don't give up
yet." He tipped the nose of the little ship down again, and curved in
toward the colony. "We can't see anything at all up this high—I just wanted
to give you a picture of the surface." He pointed off toward the rising
sun. "The first thing I want to do is to go down there close to the
surface and look for a fault
I
saw
a couple of months ago. There was a big
clordelkus
there—the nasty things like oxygen, for dessert, I guess and he'd sucked up
enough stone to start a cave-in over the tunnel. I mapped it, and didn't pay
too much attention to it, but it might get us inside the tunnels. If we spot
that, so we know we
can
get in, well start circling
the colony in widening circles. That way we should spot anything that looks
suspicious."

"And if we don't see
anything?"

"Then
we'll try hunting from the inside." The ship was quite low now, sweeping
over the jagged land in a beeline for the sun. David handed Tuck a pair of
binoculars. "I'll make several runs of about five miles over the area—see
if you can spot anything."

"What am I looking
for, exactly?"

"A deep cut."

Tuck
snorted. "The whole surface is full of deep cuts."

"Sure,
I know—but this will be sandbagged up, and you should be able to see the
bags." The ship cut even lower, and Tuck started scanning the ground as it
whizzed by, looking for anything which might be an artificial cut. The ship
reached the end of the run, made a quarter-mile arc, and sped back. The high
rocky cliffs spun by them crazily; sometimes the ship jerked up abruptly,
sometimes it nearly skidded on the ground, sending up whirlwinds of snow in its
wake. Still Tuck saw nothing. He kept gripping at the instrument panel as the ship
lurched and dropped, but there was just nothing to see.

"You
do a good job of flying," he said, as they skimmed along one of the runs.

"Lots of practice.
I'd hoped to get into rocketry, and I
learned everything I could from dad's books— but it took a lot of flying hours,
too." The leader's son looked over at Tuck. "I'm still going to get
into rocketry," he said. "Somehow, I'll get a rocket built. We're in
a perfect place to base some real exploratory work here—study Saturn and her moons,
all of them." His eyes took a wistful light. "But that's just the
start. Someday, maybe even while I'm alive, somebody is going to break the
space barrier. The
real
space barrier—"

Tuck's
eyes glowed. "You mean discover an interstellar drive?"

David
nodded. "Good old Sol is just one star. There are millions of them waiting
for us. When they build the first star-ship—that's where I want to be." He
spun the scooter around for another run,
then
snorted
in disgust. "This is getting us nowhere. Let's take the colony as a hub and
start circling."

The sun
rose
higher
and higher, a dim, small, feeble-looking sun, glowering out of a cloudless
purple sky.

Tuck's
eyes were smarting from the staring, but he kept the binoculars tight to his
pressure helmet. An hour passed as they moved slowly out from the colony in
ever-widening circles. Finally he dropped the binoculars disgustedly. "I
wouldn't see anything if it walked up and kicked me," he growled.
"All I see is gorges and cuts and cliffs—"

"Want to let me look
for a while?"

"And let me fly?"
Tuck's heart leaped.

"Think you can do
it?"

"Of course.
I won't go as low as you are, but I can
almost match it." He held on as David slid into a long, even stretch, then
rose higher and shifted the controls to automatic. The cockpit was a tight
squeeze, but they managed to shift, and in a few moments Tuck's hands were
gripping the semicircular wheel, and he felt the little scooter responding to
every touch, every movement. He brought the ship up in a high arc, exhilaration
shooting through him to the depths of his bones. His mind went back for a
second to the obstacle races he had flown back in school; then he brought the
ship in low. He found the place where they had left their circles, and closed
in, picking up a landmark in each quarter turn every time around, moving slowly
outward. The colony grew farther and farther away as the minutes lengthened
into another hour, and his hopes dwindled with every minute—

"Wait—"
David stared into the binoculars, shifting around as the ship left the ground behind.
"Wait a minute—"

"See something?"

David
scowled.
"Can't tell.
Bring her in very low,
right over that stretch there—see the gorge running off at two o'clock? Try to
follow it." His voice was excited, and he peered down, holding the
binoculars ready. Tuck swung the ship around and brought her in, scooping down
as low as he dared. He could pay no attention to anything but the path the ship
was taking, and he saw the walls of the gorge rise up on either side as they
skimmed through. And then David let out a yip of glee. "Here," he
cried. "Let me take it. See what you see! Just this side of the gorge,
over to the right—"

Tuck
relinquished the controls, peered through the binoculars at the jagged ground
below. At first he could see nothing; then, as they swooped over, he saw what
looked like a deep, black, perfectly rectangular hole—

"Looks
like a cave-in!" He cried. "Looks like it." "Is this the
one you saw?"
"Nope.
This is lots farther
out." "Think we can get into it?"

"We
can sure try!" He slid the ship down, searching for a smooth place to
land. "At any rate, we'll take a look. This may be our way into the
tunnels." He was busy at the controls for a few moments, and then the ship
was down, and the sound of the jet was dying away in their ears. In a moment
they were out, lumbering for the fault as fast as their clumsy suits would let
them—

The hole was about thirty feet deep,
perfectly rectangular at the top, but sloping up from the bottom on one side,
as though one section of the tunnel had given
way,
and
a landslide piled into it. As they stared, they could see at the bottom an
opening, leading into a black hole that seemed to disappear into the wall of
rock.

"It
is
a tunnel!" David was scrambling down the
side, staring at the other side of the hole. Tuck hesitated.

"Seems
odd there isn't an alarm, if it goes into the tunnels—"

David
shook his head. "Not so strange. The colony end of the tunnel is
completely blocked off by the cave-in. This must open into the outer end."

Tuck
peered down at him. "You think it's cut off from the main tunnel back to
the colony?"

David
nodded. "And look there—" He pointed to a large chunk of smoothly
scooped-out rock lying in the debris.
"Looks like we can
thank our little silicon friend for this, too.
Probably this cave-in is
quite recent—"

"Shall we go in?"

"Might as well—even if it is a dead
end."
David climbed down to the bottom of the slide, cleared rocks away from the
black hole, and stuck his head in. A moment later he looked back. "Come
on. This goes quite a way in."

Tuck
clambered down, careful not to cut his pressure suit on the jagged rocks.
Together they struggled through the tunnel, snapping on their helmet lamps as
the darkness closed in on them. The tunnel was seven or eight feet high, and
four feet wide, beamed heavily on the sides and overhead. Thirty yards ahead it
curved to the left and disappeared into the darkness

David
stopped after a few steps, and turned to Tuck, a strange expression in his
eyes. "Wait a minute," he said softly.

"What's
wrong?" Tuck's voice was a startled whisper.

"Everything!"
David whispered back. "I've been
thinking. I don't remember any tunnel here. No tunnel of any sort. I've
studied all the maps, and the maps say that there's a large vein of
radioactives
between here and the colony—and no way to dig
through it safely—"

Tuck's eyes widened. "This is a tunnel,
map or no map—" He stopped short, staring over his shoulder at the little
patch of light, then back at David. "You mean—"

"Has your Geiger been acting up since we
came in here?" "Not a peep."

"That's
what I thought. There's a tunnel through here, all right, but not through any
radioactive vein, and not on any map that
I've
ever seen!" He jerked his head and started down the tunnel.
"Buddy, we're on to something!"

They plodded on in silence. The stillness of
the place was oppressive, almost ghostly; their footsteps echoed and re-echoed
in the darkness. As the tunnel curved, the opening to the outside disappeared,
and they were in total darkness except for the flicker of their helmet lamps.

"Look!" said
David suddenly.

Forty
feet ahead the tunnel suddenly broke into a Y. One branch curved gently off to
the left, and then down. The other cut sharply to the right. And at the
junction was a large, dull metal object.

Tuck stopped short and
stared. "What is it?"

"A pump and blower.
There have been cave-ins before in this
tunnel—and that means it's an old one. And look at the beaming—wooden! They
haven't beamed tunnels with wood for years."

"Let's
split up here," said
Tuck
. "I'll take the
right, you take the left. Will the phones carry through this rock?"

"For
a little way."

"All right.
Look—let's each walk for ten minutes. Then come back. Meet me here in
twenty minutes."

"That's
good," said David. "There's something about this I don't like."

Tuck
waved and started down the right-hand tunnel. It cut very sharply around,
then
suddenly straightened. Tuck walked slowly, the only
sound those of his own footsteps. He shivered, suddenly, as he walked. A tunnel
where there was no tunnel on the map—beyond a radioactive bed that didn't
exist. His heart pounded wildly. It could be only one thing. But what if they
were caught down here, snooping into some strange underground vault that had
been kept deadly secret for a century—what could they do? Tuck realized with a
jolt that he hadn't thought of weapons. With the tunnel open to the outside, a
quick blow to smash his helmet would be the end—

The
tunnel widened suddenly, and he was in a small room, packed to the ceiling with
sandbags. And against one wall were boxes—he peered at them, curiously. They
were aluminum cargo boxes, stacked one on top of another. Every box had a
stencil on its side that read, "Titan Colony, via Rocket Freight,"
followed by a date—

'
ruck
!"

Tuck started violently as the cry burst into
his earphones, and his heart pounded in his throat.

"What's
the matter, Dave?"

And
then there was an excited shout in the 'phones that Tuck couldn't catch, and he
heard the jog-
jogjog
coming through of running feet
in the other tunnel. He turned and rushed back down the tunnel toward the Y
again, a thousand horrible phantoms welling up in his mind. His suit was
clumsy; his feet slipped once, and he went crashing to the ground, a sharp pain
wrenching at his shoulder, but he dragged himself up again, and rushed on. At
the Y he ran into David head-on, frantic with excitement. "I've found
it," David choked between gasps. "Come on,
I've found it—"

He started back up the left-hand tunnel, with
Tuck hard on his heels. The tunnel curved, and then dipped down, running
straight for a hundred feet or more. Then David slowed down, waving him to a
halt. Up ahead was an opening into
something
with
gloomy gray light filtering out. But David was pointing to the strip of dull
gray material that ran across the tunnel, three strips that blended almost
perfectly with the uneven ground, arranged just close enough together so that
anyone not watching the path carefully would step on one of the strips, with
the little shiny metal detonator caps that followed the strips— "
Murexide
!"