Tom Swift and His Ultrasonic Cycloplane (15 page)

"Exactly what I was about to suggest!"

Tom led his cousin back to the cave entrance, again trying to minimize the chance of being seen by the hidden watchers.

Worming their way through the covering brush, the two started through the mysterious tunnel, Ed hanging back in the shadows by about 50 feet while Tom blazed the way with his flashlight. The pathway ahead, obviously created by the hand of man, unfolded before them in ghostly outlines.

For some time they picked their way along in silence through the narrow, winding passageway. Every step took them deeper underground. The eerie darkness and the rocky walls closing them in tightly on either side began to get on Ed’s nerves. "Doesn’t this thing ever end?" he whispered as he and Tom conferred with the light off.

As his eyes became accustomed to the dark, Tom suddenly detected a glow of light, somewhere ahead. "We’re coming to something!" he muttered tensely. "I won’t use the flashlight."

A few minutes later they both grew wide-eyed in amazement as the tunnel widened into an enormous cavern bathed in a muted luminance, pale and soft as moonlight. Before them lay a fantastic sight!

Catching up to Tom, Ed Longstreet was the first to find his voice. "Great Scott!
An underground city!
This is unbelievable!" he murmured. "If I weren’t seeing it with my own eyes—!"

The pair stared in awe at the incredible scene spread out before them. Sometime in the long distant past, an unknown race of stone masons had built this whole city deep down under the earth.

"But why?" Tom asked in an awed whisper. "And what lights it up?"

There were structures shaped like pyramids, domed buildings with high arched doorways, and walls covered with strange carvings. Here and there, mounted on pedestals, were brooding statues, larger versions of the kangaroo-like animal figure. Strangest of all were the streets, with deep-carved grooves as if made to be used as tracks for wheeled carts or chariots.

Once, the visitors realized, the city had throbbed with life—busy, bustling throngs of people. Now the buildings were deserted, the streets covered with a thick, gritty layer of dust and debris.

"But where’s the light coining from?" Tom again puzzled aloud. The strange glow that made every object visible bathed the whole city in a weird, unearthly radiance. Every building stood out in soft silhouette.

Ed shrugged and Tom admitted he was baffled. "The light is coming from somewhere beyond the city, perhaps from the far end of the cavern!"

In a near-whisper Ed called Tom’s attention to the stone of which the pyramids and other buildings were constructed. Rainbow colors, in a sort of speckled pattern, shone iridescently throughout the surface of the stone, contributing a sparkle of color to the eerie glow.

Tom flicked on his flashlight and examined the stones at close range. "These colors look like more of the rare earths!" he muttered.

Ed was staggered by the announcement. "Do you mean the whole city’s built out of the stuff?"

"Out of the ore," Tom corrected. "There must be a huge quarry somewhere around here!"

Ed put a finger to his lips, nervously. "And
that
must mean our enemies are somewhere close by!"

TOM AGREED with his cousin’s assessment. But overwhelming scientific curiosity led him forward. In awe-struck silence the duo pushed ahead through the deserted streets. Still there was no sign of life. Only their own muffled footsteps and low whispers broke the stillness of the great cavern. Even the thunder of the storm, so constant that it could almost be forgotten, was scarcely audible.

Suddenly Tom gasped and halted. "Hold it!" The unexplained cavern glow revealed bare footprints in the dusty litter of the street! "Do you suppose these are the undisturbed footprints of people who lived here centuries ago?" Tom asked.

Ed pondered this. "I’ve seen many an old ruin, even some in caves. Unless the ground has been concretized in some way, as when soft clay bakes in the sun, things like footprints are slowly worn away, or filled in by dust as it falls year after year. Tom, these may be prints of the villagers who—"

The crack of a rifle echoed through the cavern!
As it died away, Tom and Ed could make out the faint, muffled sound of voices from somewhere ahead of them.

"Come on!" Tom urged. "Maybe that’s Bud or Slim!"

The duo dashed forward, picking their way through the maze of winding streets. As they ran, they were alert for an ambush. Obviously the place was not deserted after all! There might be an onslaught of enemies with rifles or a rain of stone missiles at any moment.

But nothing happened.

Finally they slowed to a walk, then halted, panting. With no further sounds to guide them, it was impossible for the rescuers to tell if they were heading in the right direction. A deadening silence had fallen again.

Ed looked at Tom. "Do you think that call was a trap?"

"I’d rather not guess," Tom replied, "but it’s also possible that this cavern has unusual acoustic properties that—"

The youth’s words were interrupted as a voice behind them suddenly called out,
"Hi, you fellows!"

Startled, the rescuers flinched and whirled around as if they had been stung. To their amazement, a man in safari garb was strolling toward them!

"Hedron!"
Tom gasped.

The zoologist’s manner was completely casual. Ignoring their wide-eyed looks of surprise, he greeted them with a smile. The man acted as if there were nothing more unusual about running into them here in this underground city than in the streets of Shopton!

"Made it back, I see," Hedron said to Tom. He offered his hand to Ed. "George Hedron," he introduced himself. Ed gave his own name and shook hands cautiously, casting many a glance Tom’s way.

"Do you mind telling us where you’ve been all this time?" Tom asked sharply. "Where are Hank Sterling and the others?"

"Oh, well," Hedron replied. "Guess I owe you another apology, Tom. The fact is, I pulled one of my harebrained stunts the other day, after we made it out of that crevice and had started into the jungle on this side. Saw a baby kangaroo while I was out scouting and thought maybe I could bag and photograph it. Never did, though—it finally got away. By that time I realized I was lost. Static made the walkie-talkies useless, you know. But luckily," he concluded, "I managed to find what looked like a trail, and here I am."

Tom shook his head in angry disbelief, trying not to raise his voice. "What do you mean,
Here I am!
How did you find the entrance to this cavern?
And where are the others?"

Hedron merely grinned. "Don’t worry," he continued smoothly, "I crossed paths with the other guys just minutes ago, while I was out filling my canteen. They’re camped in the jungle on the other side of the mountain—didn’t know about the village of huts until I told them about it. Hank wonders why you haven’t shown up in that plane of yours, by the way."

"Never mind about me!" Tom demanded.

"Oh, right, you asked how I got inside here. Well, that trail I was following led right up to a small opening between two boulders. I was looking for shelter for the night, and followed a cave all the way into the cavern. Spent the night in one of those stone temples. Quite a sight, isn’t it? Seriously, Tom, I’m sure you’re a bit upset with me, but I’ve really learned my lesson! Next time I’ll follow orders."

"We heard a shot just now, and voices. Know anything about that?" Ed asked Hedron.

"I heard it too," was the reply. "I’m sure it’s the other members of the party. I told them where the entrance is—the one I used."

In a smooth movement Tom removed his i-gun from its holster and aimed it at the zoologist, who stepped back in surprise. "There’s only one conventional gun on this expedition, and it’s with Hanson back at the
Sky Queen.
You’re lying to us."

"Now Tom, be reasonable!" Hedron protested with a half-smile. "I just made a guess in answer to the question. I didn’t realize Sterling and the boys didn’t have a real rifle among them. Why would I lie to you?"

Tom lowered his gun, but continued to stare at Hedron in suspicion. "Seems to me you’ve had a lot of luck on this rescue expedition, George. You wander off and get yourself lost, but never get into trouble. You managed to be absent during one of the attacks. And it strikes me that the night we found that skull, you were already up and walking around. Maybe you planted the skull yourself!"

Hedron winced, as if his feelings were hurt. "I really think I deserve better than that, Tom. You invited me to this party, remember?"

The young inventor’s slight nod conceded the truth of Hedron’s statement. He holstered the i-gun. "I apologize if I’ve jumped to one conclusion too many," Tom said. "I’m on edge because we found evidence that Bud and Slim made it through the crash and are being held prisoner—maybe here in this cavern!"

"I understand," responded the zoologist. "No hard feelings. I saw the wrecked plane outside."

"We’d better try to find who shot off that gun," Ed urged crisply. "We’re wasting time."

As they continued to walk along in the same direction as before, Hedron continued to talk, keeping his voice low at Tom’s order. Looking around at the ancient buildings, he went on, "Isn’t this an amazing spot? I’ve never seen or heard of anything like it! Have you, Longstreet?"

Before Ed could comment, they heard voices again, louder, from somewhere to the side.

"It
must
be your friends!" Hedron exclaimed. "Come on. Let’s go!"

Breaking into a run, the three men raced in the direction from which the sounds had come. In a few moments they reached a spot where the narrow, twisting streets widened into a plaza or public square, paved with multi-hued stone tiles of pentagonal shape. With muffled gasps of amazement, Tom and his companions pulled up short.

A fantastic scene met their eyes, illumined by huge floodlights that reflected down from the high cavern ceiling and cast a glow throughout the city. Across the plaza trudged a group of dark-skinned natives in single file. Their ankles were manacled and linked by chains, while on their shoulders they bore heavily loaded sacks like those stashed in the entrance tunnel.

"So this is where the missing villagers have been hiding!" murmured Ed, dumfounded.

Beyond, ranged against the wall of a broad, low building, stood more of the natives, oddly smeared with paint and covered with garments woven of leaves. It was several seconds before Tom realized the purpose of this strange garb.

"It’s for camouflage—jungle camouflage!" he whispered to the others as they shrunk back into the shadows. "Those men must be the invisible army of stone snipers!"

Tom grabbed Ed’s arm and roughly pulled him further into the portal in which they were standing. This was no time to risk being seen. A deadly hail of stones might follow when their presence was discovered. But no sooner were they huddled inside the arched doorway than Tom realized that only Ed had accompanied him. George Hedron was still standing outside!

"Come in here!" Tom hissed. "If those men spot us, they may attack!"

But the zoologist seemed completely unaware of any danger. He took a few steps further into the street. Standing in plain view of the plaza, he scanned the scene with a keen, intent air.

"What’s wrong with him?" Ed puzzled. "Has he gone deaf?"

Tom watched the scientist through narrowed eyes and muttered, "It could be that he doesn’t
want
to hear me!"

There was something odd about Hedron’s attitude. He seemed poised for action—like a panther crouched to spring. By this time, Tom’s distrust had grown to a near certainty that the zoologist was up to something.

Meanwhile, the present danger was too great to speculate about Hedron’s motives. Any second now the jungle snipers might discover the intruders. In a tense, heart-pounding silence, Tom and his companion waited. Nothing happened. Apparently the sling-warriors still had not discovered that they were being spied upon.

"What do you make of it?" Ed asked.

"Beyond me," Tom replied. He edged forward and peered out cautiously. The column of chained natives was still plodding across the public square with their heavy loads. Either the snipers were focusing all their attention on the slaves in order to prevent any break for freedom or else they were too busy talking among themselves to notice Hedron.

Suddenly Tom gave a startled gasp. As the last few slaves trudged past, two bedraggled but recognizable figures were revealed propped sideways against a long-dry street fountain.

"Bud!"
he cried out without thinking.

Throwing caution to the winds, the young inventor rushed out of his hiding place. In the sudden surge of excitement and relief that swept over him, nothing else mattered except to reach his pal’s side!

As he raced toward the fountain, with Ed at his heels, Bud and Slim turned their heads to look, but otherwise remained motionless. What was even more strange, neither showed the slightest sign of recognition!

In full view of the phalanx of warriors, Tom dashed to Bud’s side. "Bud!" pleaded Tom in a low, tense voice. "What’s wrong with you? Don’t you know me?" He turned to Slim Davis. "We’re your friends!"

Neither made any response. Tom stared in horrified surprise. He saw, for the first time, that both fliers were chained. And they regarded him with a blank, unseeing gaze, as if staring into empty space!

"Steady, cousin!" Ed Longstreet warned as Tom groaned in shocked dismay. "They’ve been brain-washed or something. They’re both in some sort of stupor."

In desperation Tom glanced about the plaza, trying to figure out his best move. Another horrifying sight met his eyes. Some distance away, women and children of the tribe cowered against the lofty arching walls of the cavern, apparently completely subdued.

Just then a new development caught the rescue party’s attention. A small, sandy-haired white man had darted out from one of the buildings like a scurrying rat. In one hand he lugged a big, heavily laden sack. His other arm cradled a queer-looking device like nothing Tom had ever seen before. Cylindrical in shape, with a hand-grip beneath, it was covered with white ceramic insulation. From the front end protruded two thick coils which looked like the antennae of some monstrous insect.