“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 the 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 —

  “Tuck!”

  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-jog-jog 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!”

  David nodded. “I barely spotted it.” Gingerly he stepped between the strips, then across to the other side, and Tuck followed, his heart in his throat. A perfect booby trap for one who wasn’t watching closely for just such a thing. On the other side they hesitated for a moment; then David urged him on with a wave of a hand, and they hurried again toward the opening, and stopped short, almost teetering on the drop that lay before them. And they stood there and stared, peering dumbfounded at the incredible thing they saw there before them in the gloom —

  It was not a vault, nor a battle station, nor even a stockade. It was a ship, standing upright on its jets in a tall, narrow crevice, with the open top camouflaged and sealed with gray plastic sheeting that blended perfectly into the rock. A pale gray light filtered down from above, and the huge ship stood like a ghost, tall and silent in the gloom —

  Tuck stared at David, dumbfounded. “But — but a ship! But there’s no place to go with a ship! They’d be hunted down, if it took a thousand years. There’s no place in the Solar System they could hide — ” His voice broke off with a gasp as the implication of his own words struck him.

  There was only one place where a ship would be beyond pursuit. Completely and utterly beyond pursuit.

  There was only one conclusion possible.

  The ship was a star-ship.

  14

  Trapped!

  TUCK BENEDICT AND David Torm stared at the ship in the gloomy crevice, stared speechless at the long, slender form as the implication sank in. And then they were both talking at once, forgetting where they were in their amazement at the ship in the crevice before them. A thousand questions roared through Tuck’s brain, a thousand pressing questions, questions that came out with incredible, staggering answers.

  “But where could they have gotten it? There’s never been a ship like this on Titan for anything except regular cargo runs — and how could it be a star-ship? How could it take five hundred people — ”

  “I don’t know, but this is the plan — it must be.” David stared up at the long, slender, finger-like structure. “It must be the Earth ship that crashed. That was a troop-ship — built to carry three or four hundred men — ”

  “But that was lost clear around on the other side of the planet!”

  “I know. But the Security Patrol never found it, did they?”

  “No — it was an impossible task. Titan is almost half as big as Earth. What chance would a search party have? The ship may have fallen into one of those gorges, and covered over with frost so it was completely invisible from above.”

  David Torm nodded. “But everyone knew a ship had crashed. There was no colony here then — but when the colonists first worked out the plan, they knew there was a ship — somewhere — ”

  “And they must have found it.” Tuck’s voice was filled with awe. “They must have torn it apart, bit by bit, hull plate by hull plate, tube by tube — and brought it here.”

  David jumped up, excitedly. “That’s right! Just a few men, working in secret, dragging all that metal clear around from the other side. And then they found this crevice here to reassemble it — and it’s taken them a hundred years.”

  Tuck shook his head, still incredulous. “And the tunnel?”

  “They must have built it in secret, and then made up a story about a vein of radioactives to keep the other colonists — and the Earthmen — away.” He stared down the black hole where the jet tubes disappeared, and the fins on which the ship rested.

  “It still doesn’t add up!” Tuck burst out. “Where did they get an interstellar drive for it? The greatest minds in the world have been working on Earth for two hundred years to find a drive that would take a ship to the stars. They’ve had laboratories, money, government support — and they’ve never found it. They say it’s theoretically impossible.” He turned to David, his eyes wide. “How could the colonists have found something that all Earth’s technology couldn’t find?”

  David shrugged. “I couldn’t even guess.”

  “Well, I’ll tell you one thing — I want to see those engines!”

  “I don’t know if we should go on board her or not — ” All of a sudden David was trembling. “I don’t like this, Tuck — I’m scared of what’ll happen if they find us — ”

  “If the colonists have developed an interstellar drive, it’s in that ship. You can stay here if you want. I’m going in.” Tuck started up the ramp toward the dark port in the ship’s side. David hesitated, then started up after him. “Look,” he said, pointing upward at the scaffolding. “They’re still finishing the hull plates. They must have built it from the inside out. And it looks almost finished — ”

  They stepped from the ramp into the ship, and Tuck felt a thrill unlike anything he had ever experienced. Here was the adventure he had dreamed of all his life; here was the ship that was built to go to the stars, built to leave Earth and Earth’s puny Solar System light-years behind, built to speed straight as an arrow — where? Alpha Centaurus? Cygni? Arcturus? Here was the greatest frontier of all, the frontier that had never been crossed — the frontier physicists on Earth had said could never be crossed —

  Because there was no drive for an interstellar ship. The weeks and months in transit between Earth and Mars or Venus or Titan on fast Interplanetary Atomics were insignificant compared to the years — the centuries — that would be required to travel with them to the stars. Man’s life was too short to make such a trip possible without an interstellar drive.

  And yet, in the bowels of this strange secret ship — was the drive there? Could the colonists, in their desperation, have discovered genius in their midst, genius to solve the immense mathematical and technical impossibilities of a space-warp, of faster-than-light motion? The boys made their way along the narrow dark corridor of the ship, moving downward, still downward to the rear of the ship. They passed a huge room, and stopped, peering through the hatch at the tier upon tier of soft, curved mattresses, set at 45° angles from the floor — the acceleration cots. This was the troop hold, the quarters that had been built to carry the Security Patrol troops, over a century ago — how many were there? The boys stopped, and counted the cots on the first row, and counted the number of tiers. Five hundred. The ship was to carry the entire colony. There was no doubt of it.

  Then in another room a bright light shone, and when they walked in, they found a sealed lock and an inner hatch. They moved curiously into the lock, and sealed the door behind them, heard the automatic pumps whir, until the inner hatchway sprang open, and they walked into a brilliant flare of lights. It was a large room, lined with mercury vapor lamps and carbon arcs, a room so damp and hot that their cold suits were drenched with water, and they stood in little individual rainstorms, until they could peer through their dripping helmets at the row upon row of green things, growing plants in huge tanks. The hydroponic tanks — to provide growing food, to cleanse the great ship of carbon dioxide and to replenish the feeble stores of oxygen the ship could carry for five hundred people. They wiped the water from their suits in sheets, and moved back through the lock. Out once again in the icy corridor the water froze in solid sheets upon them, and tinkled and crashed to the floor as they broke it off. But still they moved to the rear, on toward the wonderful engines that lay in the bowels of the ship.

  Tuck knew the layout of the ship; he had explored the Earth ship in minute detail during the passage out to Titan, and was familiar with what to expect of such ships. But David had never before traveled on a rocket ship; his acquaintance had been confined to a brief visit now and then, and he followed Tuck with open mouth and wide eyes, finding amazement in every turn of the passageway, excitement in every compartment. And when they opened the hatch that led to the engine rooms and generators David could hardly believe that a single ship could carry propelling engines so huge.

  But Tuck didn’t wait for his friend. In an instant he was down among the generators, examining the engines, moving swiftly from one great pile of machinery to another, eyes growing wider, more incredulous by the minute. And when David finally caught up with him, he found the Earth boy sitting stunned on an auxiliary generator, staring about in bewilderment. “What’s wrong, boy? Are you sick?”

  “Sick? No — no. I’m — I’m fine. I — I just can’t understand it — ”

  David glanced around nervously. “Understand what?”

  Tuck stared up at him, hollow-eyed. “The engines!”

  “What’s wrong with the engines?”

  “There’s nothing wrong with them. They’re perfectly good, common, ordinary, everyday interplanetary atomics. There isn’t any interstellar drive on this ship!”

  David sat down heavily. “I thought not. Because if there were, it would be easy for them to escape. And my father thought it would be suicide for them — ”

  Tuck nodded, speaking almost as if he were in an unbelievable dream. “It would be suicide. They would have to make this ship a colony — a permanent colony, drifting endlessly in space. They would have to take their bearings, and head out into deep space until their power gave out — and then they would have to drift. They would keep going, and they would reach their star — someday. But it would take three hundred years.” He looked up at David. “Do you realize what that would mean? That would be twelve generations to live and die aboard this ship before it reached its destination! And what might they find, even if they reached it? A planet they could live on? Who knows? There might not be any planets in the system they reached — or there might not be any oxygen, any food. They would never know until they got there — and they might never even survive to reach it — it would be almost hopeless to try and support five hundred people, and their children, and their children’s children, on a ship like this for three hundred years.”