CHAPTER XII
Citadel of Fear
JOAN THORN paused. They had been following the huge drain for half an hour, and had now reached a point where a smaller drain-tube opened into it from the right.
'This must be one of the citadel drains,' Thorn muttered, flashing her red beam up it. 'Come on, we'll soon find out.'
'We'd better not stay down in this maze of pipes too long,' warned Sua Av. 'The rains will start again when dawn comes, and these tubes will be full of rushing water.'
Joan Thorn was clambering into the smaller side drain. It was so small that she had to go forward in it on hands and knees. It sloped very gently upward, and its floor was damp.
She led the way, the little red beam of her fluoric lamp lighting her forward. Sua Av followed her closely, and the big Mercurian brought up the rear.
Thorn guessed that by now they must be passing under the wall of the great fortress. Her hopes were running high. So far, they had met no barrier.
Then suddenly, Thorn met the barrier. And she almost died before she realized it.
The little tubular fluoric lamp she held outstretched in front of her suddenly flared red hot, its chromaloy case starting instantly to melt. Thorn recoiled with a smothered exclamation of pain and surprise, dropping the redhot thing. They were plunged into absolute darkness,
'What is it?' exclaimed Sua Av anxiously.
'I don't know. Something ahead melted my lamp before I could draw back,' Thorn answered, her voice wiretaut in the darkness. 'Pass me your lamp, Sua. We've run into some devilish trap!'
The Venusian passed her lamp forward. Thorn, without venturing any farther forward, snicked on the beam.
The red ray quivered up the gently sloping black cement tube. Thorn stared tensely. There was nothing ahead—nothing except a row of small holes across the curved floor of the drain, and a similar row of holes in the roof exactly above.
'I can't see anything,' said Sua Av. 'Your lamp must have burned out accidentally.'
'Wait,' said Thorn tensely.
She tore a bit of cloth from her jacket, and cautiously pushed it forward until it was over one of the row of holes. Instantly the cloth burst into flame and vanished in fine ashes.
Joan Thorn felt cold sweat stand out on her brow. She knew now the invisible death she had nearly, blundered into.
'There's a web of heat-beams here across the drain,' she said hoarsely. 'A little trap fixed up by Hasna Trask's guards for anyone who might try to enter the citadel this way.'
The nature of the diabolical trap was clear. Buried somewhere near the cement drain was a generator of heat beams—those 'focused'rays of radiant heat which were produced in a mirrored inertrum chamber by transformation of atomic energy into vibratory force in the proper octaves. Such beams had an effective range of only a few feet, but were deadly within that distance.
'The beams are projected through three holes in the floor and disappear through the holes in the roof of the drain, to be dissipated above,' Thorn said. 'It's a fiendishly clever idea. Anyone crawling up this drain would never see anything until she blundered into those beams that would sear through. and kill her instantly.'
'Hell, we can't pass this until we find some way to shut off these beams!' swore Gunda Welk from behind.
Thorn frowned tensely. 'We can't get at the generator of them,' she muttered. 'That must be located outside the drain. It would take lots of tools and time to dig down to it.'
'Inertrum is proof against high heat,' Sua Av said hopefully. 'If we had some inertrum plugs to stop those holes the beams come up through—'
'That's fine,' rasped Gunda angrily. 'Now all we have to do is to go back out in the city, order a nephew set of inertrum plugs, and come back here with them. The secret police out there wouldn't think of bothering us while we're doing all that.'
'Shut up, Gunda,' Thorn said. 'I've an idea which might work.'
She fumbled in the pouch that was still attached to her belt. Out of it, she drew the gleaming white slith teeth they had taken from the monsters they had slain in the fungus forest. There were a dozen of the teeth, long, conical fangs an inch across at the root.
'These slith teeth might do the trick,' Thorn muttered. 'They're one of the hardest and most perdurable substances in the system, remember—almost as hard as inertrum. If we plugged the heat-beam apertures with these—'
'They couldn't last more than a few seconds before the beams burned them out!' Sua Av exclaimed.
'A few seconds ought to be enough for us to get past,' Thorn retorted. She hesitated, then added, 'The last woman will run the most danger. We'll back down to the main drain, and I'll, take the rear position.'
'You'll not!' Gunda Welk declared. 'Hell's name, do you want to play around in these slimy pipes all night? Go ahead and put the teeth in those holes, and let's got on—if it works,'
'All right,' Thorn said grimly. 'When I give the word, jump after me as fast as you can, and don't knock any of the teeth out of the holes!'
Thorn rapidly prepared for their precarious stratagem. There were six holes around the perimeter of the drain from which the deadly, invisible beams emerged. She took the six most regularly-shaped of her slith-teeth, and laid them in readiness.
Then with the end of her lamp, Thorn swiftly pushed the teeth into place. As each big white tooth was shoved forward, it became a conical plug to close the beam-aperture. By the time the sixth tooth was tamped into place, the first one was already charring and smelling.
'Come on!' Thorn cried, and plunged forward in a scrambling leap through the teeth-plugged circle of holes.
Sua Av followed instantly, the Venusian's wigged head butting into Thorn's back. A moment later, Gunda Welk caromed into the Venusian from behind with battering force.
'Jackyet's on fire!' gasped the Mercurian, beating at her side. A smell of scorched cloth filled the dank air.
There was a frantic squirming in the cramped tunnel as the other two Planeteers tried to help Gunda beat out her smoldering jacket. She and Sua Av soon had it extinguished.
'Are you hurt, Gunda?' Thorn asked anxiously.
'No, just my side scorched a little,' panted the Mercurian. 'One of those teeth burned clear out just as I jumped. It's lucky it was one slith instead of in the middle!'
Thorn glanced back past them. The slith-teeth with which she had plugged the apertures had vanished. Even that super-hard substance had been charred away in a few seconds by the beams.
'Let's get on,' growled the Mercurian in a moment. 'These damned drains aren't exactly a pleasure resort.'
Again Thorn started forward on hands and knees, lighting the way with her red beam. She moved with extreme caution, alert to detect the presence of another invisible, deadly web.
But they met no more such barriers. Presently they reached a place where the drain forked into five smaller tubes.
'Which one?' whispered Sua Av to her.
'We'll each take one, trace it and come back and meet here,' Thorn muttered. 'One of them ought to lead to the dungeons.'
Thorn crawled into the right drain tube. It was so small she had to inch forward by creeping. It slanted upward also.
Blue light finally glimmered ahead. Thorn extinguished her lamp and stealthily crawled on. She came to the end of the drain, which was closed by inertrum bars set in the cement, over her head.
Cautiously she peered upward. The grating over hers was set in the cement paving of a large court surrounded on all sides by the dark, towering mass of the citadel. Krypton lamps cast a blue glow on spaceships parked in the court, three swift-lined small cruisers. Two armed guards paced to and fro beside them.
'Hasna Trask's personal spacecruisers,' Thorn muttered to herself.
She backed down to the fork where the drains diverged. Gunda Welk and Sua Av were just emerging there also.
'The dungeons are up there at the end of that pipe!' Sua Av whispered excitedly, pointing to the second drain.
'Come on, then,' Thorn s
aid swiftly.
She led the way, all three of them crawling up the narrow pipe the Venusian had explored. Its opening, also, was barred by inertrum bars set in the cement.
Thorn peered up through the bars into a short blue-lit corridor, along whose walls were the inertrum doors of cells. Almost all of the cells seemed unoccupied, their doors half-open. No prisoner stayed long in Hasna Trask's dreaded private dungeon!
'It's Trask's dungeon, all right,' Thorn whispered. 'And no guards in sight. Go back down the pipe a little.'
The other two Planeteers obeyed, all three backing down the tube a little way. Thorn drew her pistol, sighted carefully at the grating above, and pulled the trigger.
The little atom-shell exploded in a small, brilliant flare of atomic energy, with a thudding reverberation. The flare burned away a mass of cement at one side of the grating, completely exposing the ends of the imbedded inertrum bars.
Thorn clambered eagerly up to the grating at once. At the same moment she heard a cry of alarm from up in the corridor. Two Saturnian guards came rushing out of one of the cells, dropping a flask of fungus wine they had been secretly drinking, and drawing their atom-pistols. The thud of the atom-shell had roused them.
They saw Thorn's head below the grating and fired at her instantly. Their shells struck the floor in front of the grating and a flare of blinding light and scorching heat hit Thorn's face. She fired her own atom-pistol, triggering quickly. More flares of energy burst brilliantly beside the two Saturnian guards, down the corridor.
The two green-faced soldiers crumpled and lay still, in a scorched and lifeless heap. Thorn waited, her face wild in the pale blue light, gripping her weapon. But the swift thudding of the shells was not followed by any further alarm.
'Those must be the only guards on duty. inside the dungeon,' Thom panted, tearing away the freed inertrum bars with quivering hands.
The Planeteers scrambled hastily up out of the drain into the short single corridor of the dungeon.
'Listen! I hear someone!' Sua Av exclaimed.
Then the other two comrades heard. It was a voice from the farther end of the corridor, a distant, monotonous, strangely metallic voice speaking on and on.
'Erebus—won't think of Erebus—think of anything but Erebus—won't think of Erebus—'
Thorn started wildly. 'Erebus? That must be Lann talking! Come on!'
'It didn't sound like a human voice,' Gunda muttered, as she and the Venusian raced after Thorn.
They leaped over the scorched bodies of the dead Saturnians, and on down the corridor. The voice came from the last cell in the passage. Now they heard it more clearly, and it was not a human voice. It spoke in cold, metallic, inflectionless tones, on and on without stopping.
'I mustn't think of Erebus—mustn't think of the secret! Keep my mind on something else—'
Thorn reached the door of that last cell. She peered through the little grating in the inertrum door. And her brown face froze, her eyes widened wildly, at what she saw.
'Good God, it's Lann!' she whispered hoarsely. 'They've got a psychophone attached to him!'
The cell into which Thorn wildly gazed was a windowless cubicle, lit by a single krypton lamp in the ceiling. Under the uncanny blue glow, in a metal chair to which his arms and legs were tightly strapped, sat Lann Cain. The boy's slender little figure was sagging in his bonds, his eyes were closed, his white face infinitely weary and exhausted. It was not Lann who was speaking, but the complex machine that was attached to his head.
Tiny, needlelike incisions had been made in the base of Lann's skull. From them, two thin black wires ran upward to the mechanism suspended above him, a compact complexity of transformers and vacuum tubes, upon which was mounted an audio-speaker.
The metallic, monotonous voice came from that audio-speaker. It was still speaking steadily on, and everything it said was being taken down upon the moving tape of a recorder whose microphone hung in front of the speaker.
'Think of something else,' the metallic voice came from the speaker as the Planeteers listened. 'Think of the Zone—of Stilicha—of my father—'
'A psychophone!' repeated Sua Av, wide-eyed. 'So that's how Trask is trying to get the secret of Erebus from Lann!'
Thorn too was thunderstruck by the ingenuity of the means being used to secure the boy's secret knowledge.
The psychophone was a mechanism that made thought audible. Once it was connected to a subject's nerve centers, every conscious thought in that subject's brain was translated into mechanical speech by the machine and spoken aloud. That was accomplished by transmitting the tiny electrical neural currents of the subject's thought-impulses into a complex scanner, in which the particular vibration of each thought actuated the nearest word or phrase that expressed that thought, in the phono-recorded vocabulary of the thing.
The machine was the recent and little-known invention of a Venusian psychologist. It was a far-advanced adaptation of the ancient encephalograph, the device used by Earth scientists as far back as the third decade of the twentieth century to record thought as a varying electrical vibration.
Lann Cain was sitting silent, his eyes closed, but every thought that passed through his mind was being remorselessly translated and spoken aloud by the mechanism above his head, and taken down by the recorder so that it could be studied later at leisure. He could not possibly keep from thinking, and whatever he thought, the psychophone spoke forth.
'M-my mother,' the mechanical voice was speaking on as Thorn and her comrades peered incredulously .' Wish my mother were alive. She would get me out of here. She would—'
'Lann!' Thorn whispered tensely into the cell.
The boy opened his eyes. Their blue depths were wells of utter weariness and hopelessness as he stared at Thorn's face through the grating in the door.
His face hardened in bitter hatred as he looked at her. He said nothing, but the psychophone's mechanical voice spoke his thoughts.
'Saturnian—hate all Saturnians, now. Green faces peering at me—trying to make me think of Erebus—'
Thorn, for a moment stunned by his bitter reaction, suddenly understood. She and her comrades the green stain on their faces, were still disguised as Saturnians.
'Lann, it's I, Joan Thorn!' she said hoarsely. 'It's the Planeteers!'
Lann stared unbelievingly. Then as he recognized her features, his tired eyes lit with incredulous joy.
'Joan Thorn?' he whispered. That was all that came from his lips.. But from the psychophone overhead, there sounded his thoughts in that metallic voice.
'Joan Thorn, I love you! I love you!'