Alan E. Nourse

by Trouble on Titan

  And the Big Secret? There was the question mark, the key to the whole problem. It kept thrusting itself upon Tuck's mind, insistently, and he reviewed what David had said about it. It seemed incredible that a plan could have been prepared in absolute secrecy for over a hundred years—and what could possibly take so long? What kind of plan could possibly offer the colony any sort of hope whatsoever?

  Slowly, as they bounced along, things began to line themselves up in Tuck's mind, like the outlines he had made in school. When you have a problem, write down everything you know about it—all the facts in one column, all the unknowns in another column, all possible solutions in another. Then eliminate.

  All right. Problem:

  The Big Secret—

  A plan, a last-ditch plan, an escape, a way out that the colonists could use if they were driven against the wall. Check.

  A plan that was guided by a very few people, kept in strict secrecy from the rest. Check again.

  A plan that had taken over a hundred years to set in readiness. Check.

  A plan that would take care of all five hundred people in the colony, a plan that would allow them to blow up the mines and the colony they had been living in. Check.

  Hold it. Slow now. Something was missing there-Tuck shifted his weight as the half-track slid down a grade, then hit the bottom and lurched up again with a roar. A plan, a last-ditch plan, a way out—

  A way out that Anson Torm thought was suicide, and risked being branded a traitor to oppose. But Cortell was eager to set it in motion—

  A difference of opinion, then.Odd? Very odd. A last-ditch plan that was hazardous, terribly hazardous, but which might work. That made sense! There was great risk involved. It might be a way out, or it might be death. Cortell was willing to gamble; Torm was not— But that meant that it might be a permanent way out for the colonists, if it worked. A way out in utter defiance of Earth-Tuck chewed his lip. An underground station? Could that possibly, even conceivably, be a permanent way out?

  Never. It just didn't add up.

  But what else?A ship to escape in? To escape where? What kind of a ship would carry five hundred people and let them hide out in a Solar System teeming with Security Patrol ships, a ship that would be hunted down to the bitter end. Possible? Even conceivable?

  Never. There could be no escape off the planetoid itself. There was no place to go, no place to hide.

  But what? Open war against Earth? Even more ridiculous. There were big enough ruthenium stores on Earth to last for several weeks. The colonists would be wiped out, utterly massacred.

  Then what was the Big Secret?

  It was something big, and something desperate beyond belief.

  It was something on Titan.

  Therefore—it was something that could he found.

  Tuck stared at his father, an impossible plan forming in his mind. His father wouldn't listen to reason now, he wouldn't believe anything the colonists told him. Nothing would change his father's attitude at this point but facts—cold, clear, unarguable facts. And there was only one fact that would make much difference. The plan. The true nature of the Big Secret. If Tuck could get back to the colony, somehow, contact David there, there might still be time. Time to find the Big Secret, wherever it was, whatever it was, and bring back the facts to lay before the two men.

  Tuck's heart pounded, and he tensed against the gripping bar, the plan crystallizing in his mind. Carefully he began watching his father drive the half-track. He'd never driven it before, but he seemed to be doing all right, and Tuck had watched David drive it. His eyes narrowed thoughtfully. There wasn't any other vehicle at the ship that could travel over this kind of ground. If it were possible—

  After a long, unbearable time, the 'track mounted the last rise, and tumbled over the rim, down into the shallow crater where the Earth ship stood, tall and shiny. Already there was a brightening on the horizon —the night was short, and it was almost dawn. Weird shadows were creeping out of the blacks and grays, showing the surface of the valley in more detail.

  "We'll need some sleep," the Colonel was saying, "and I think we'd better get it while the getting is good. Well have the men alerted as soon as anything pops, and have them radio for a troopship from Ganymede right now—it can't be too soon." He glanced over at Tuck. "And I think you'd better stay on the ship, no matter what happens. I've had no right to drag you into this in the first place, particularly since I've made such a nice mess of things. And don't worry too much about your young friend—I've a notion he'll make out all right."

  Tuck nodded, his conscience jabbing him sharply. It was a desperate decision, a desperate chance to take, yet he knew he had to take it. It would mean disobeying his father—but there would be no answer but violence and death if he didn't do it. And they could find the answer, if only there were time—

  The half-track stopped thirty yards from the crane, and the top sprang open with a hiss. The Colonel clambered out, stepping down to the frigid ground. Tuck leaned over the back seat, as though hunting for something in the storage space, his heart beating in his throat, moving as slowly as he dared, until he saw his father start walking away from the half-track. Then, like lightning, Tuck snapped the switch that slammed the hood back down; in the same motion he started the pump at top speed, its motor roaring in his ears. For the briefest instant he caught a glimpse of his father's face, startled, realization dawning; then he revved up the motor, jerked back on the steering bar, threw the gear into reverse, and felt the vehicle lurch back thirty feet from his father. The Colonel started running toward the vehicle, shouting, and Tuck desperately snapped on the emergency lamp, catching the Colonel full in the face, blinding him for an instant. Then, with a roar, the half-track pivoted, started rolling crazily away from the ship again, headed up the path that led to the colony. Through the back of the hood he saw his father's tiny figure, running after the half-track for a few steps, then stopping, standing still, just staring. And then Tuck wrenched his mind away, forcibly thrust his betrayal out of his mind, concentrated on guiding the lumbering vehicle.

  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