Part 9

"Don't stall, professor!" the man ordered curtly. "You know what I'm driving at. In case you don't, I'll enlighten you. I'd like to have a man like you on my side and I'm willing to pay a big price, too. I'm going to organize a bunch of my friends and declare the Fifth Dimension as my inviolate domain. In exchange for your services and help I'd make you my right hand man. With your brains and my guts, we could go a long way, but listen! I don't really need you! I can have those devices duplicated anytime! I'm merely giving you a chance to live. What do you say?"

Bribery! But why would this man try to tempt him? What could he, Mortenson, do that would aid the underworld, unless it was to build Fifth Dimensional apparatus to outfit the phantom criminal's followers?

Mortenson studied the man meditatively, his brain working rapidly. So the fellow wanted his services, eh? Why, when he could have the apparatus duplicated by some corrupt scientist? Or could anyone duplicate them at all, beyond himself? Mortenson's eyes narrowed as he grasped the full significance of the man's bold proposition.

The apparatus could not be duplicated by anyone but himself! That was why the bandit was so intent upon enlisting his aid to set up a domain of terror in the Fifth Dimension, a domain that would prey unmercifully upon the world in which he now stood. That was Mortenson's conclusion and it was correct. The bandit had tried elsewhere to have the apparatus duplicated and had failed. Without Mortenson's help his mad, daring scheme would also fail.

Mortenson stroked his chin in silence. His attitude was that of a man deciding an important issue in deep thought. The bandit squinted at him shrewdly, a leering smile on his almost diabolical lips. Then Mortenson addressed him.

"What about the creatures in the Fifth Dimension?" he asked curtly.

Before the criminal could make a reply, there came the sound of heavy footsteps from the hall leading to the laboratory from the outside. Instantly the man tensed, jerking his automatic in line with the door. Mortenson's heart pounded like a triphammer. Chief Steckel and his men had arrived. But were they in time?

The phantom bandit backed slowly toward the work bench on which lay the ten completed sets of Fifth Dimension apparatus. A heavy knock rattled the laboratory door. The bandit squinted at the scientist.

"Well, what about it, Mortenson?" he hissed coldly. "You with me or not?"

The scientist winced as the man levelled his automatic at him.

"I haven't had time to decide," he replied in a quivering voice. He glanced at the door. It was barred, but through it he could hear the voices of the men outside.

"Then I'll be generous with you and give you twelve hours to make up your mind," he jeered. "Meantime I'm going to take care of these ten sets of apparatus."

A wave of fear and desperation went over Mortenson as he realized that the man was going to make away with the Fifth Dimensional devices. He felt an urge to cry out to Steckel to smash down the door, but the bandit's pistol prevented it. In his pocket lay his own automatic, but it was useless now. If he made one move to draw it the bandit would undoubtedly kill him without a qualm.

Suddenly he seemed to calm. He overcame a wild roving of his eyes and settled them on the bandit. Then slowly he advanced toward the man, speaking in a lowered voice. "You say there's a million in it for me?" he asked in a half whisper.

The bandit nodded and relaxed. "Yeah!" he said quickly. "And more if you play ball with me."

"How do I know you will not double-cross me?" Mortenson asked, advancing carelessly.

"When I give my word, I don't go back on it," the bandit replied with a perfunctory shrug. He lowered his automatic a trifle, impressed by the scientist's interest in his proposition.

"All right!" said Mortenson decisively. He halted within four feet of the bandit and jerked his thumb at the door. "Speak low," he said, "or they'll hear you. Now, it'll take twenty thousand to start building apparatus on a big scale."

"That's fine," the bandit nodded, pulling a roll of bills from a pocket and glancing at it carelessly. By sheer force of desperation, Mortenson lashed out savagely and brought both hands down on the man's gun-arm. Instantly the automatic spat like a whiplash and then clattered to the floor. With an oath he swung around at the scientist, his roll of bills scattering.

Screaming at the top of his voice, Mortenson lunged himself bodily at the phantom bandit. His arms caught him around the waist. They fell to the floor, Mortenson yelling at the officers outside.

"Steckel!" he screamed wildly. "Break down the door! BREAK IT DOWN!"

A savage foot caught Mortenson on the chest and sent him spinning. There was a rending crash of splintering wood and into the laboratory rushed Steckel and his men. Mortenson stared at them in a daze.

"Get him, Steckel!" he shrieked. "He's lying on the floor near the bench!"

Automatics drawn, the officers glanced toward the bench. Above it hovered a pale blue haze that shimmered like a curtain of smoke. From it came a venomous curse that all could hear before the phantom bandit vanished completely into the Fifth Dimension.

"I'll get you for that, Mortenson!" the bandit snarled. "You dirty double-crosser! I'll get you if it's the last...." His voice trailed off into nothing as he penetrated the veil between the two worlds.

"Did you hear that, Steckel?" Mortenson gasped, rising.

"What's it all about?" Steckel grumbled, mystified.

"The phantom bandit!" exclaimed the scientist. "He was in here ... you heard his voice! I tackled him in an effort to hold him, but he kicked me and got away."

Mortenson rushed to his work bench. On it lay the untouched apparatus. His mad lunge at the bandit and the appearance of the officers had thwarted the desperado's intentions of making away with them. The scientist gave a sigh of relief and turned to Steckel.

"Let's get started, chief," he said urgingly. "There's no time to lose. The bandit is somewhere close and we must catch him. My life isn't worth a counterfeit penny now!"

V

_Into the Fifth Dimension_

With Chief Steckel and eight grim-faced officers including Barton and Riley lined up, Mortenson hurriedly gave instructions on the operation of the Fifth Dimensional apparatus. Each man wore a set, giving them the appearance of gargantuan creatures of another world, with the projecting eyes, tight-fitting helmets and wide metal belts. They looked like men from Mars, but Mortenson had no time to make such observations or any comparisons.

He had made some important improvements over the first set of apparatus taken by the phantom bandit. The new ones were equipped with a small panel that hung down over the chest. On this were three buttons arranged in numerical order so that the wearer could press number one and start the electronic vibrations coursing gently through the body, and on down to number three which actually neutralized the veil of invisibility between the two worlds. This arrangement, he thought, made the apparatus fool-proof.

Finally the scientist donned his own set. As he swung the lenses before his eyes he glanced along the line of men. Each officer held an improved model sub-machine gun capable of firing a hundred rounds of ammunition at one loading. They were short, squat weapons with cartridge disks on the barrel just before the stock grip. A grim set of men, he concluded, who would stop at nothing to apprehend the desperado who struck without warning like a _fer de lance_, leaving death and terror on his invisible trail.

"Are you all ready, men?" Mortenson inquired suddenly. A murmur of assent ran along the line. "Remember what I told you ... in event any of you are wounded in the world which we are now to enter and want to transfer yourself back here in a hurry, press all three buttons simultaneously. The vibratory reaction will probably knock you out for a moment, but it will not harm you. Take note of your surroundings when we enter the Fifth Dimension so that you can mark the spot for the return to this laboratory. Now, gentlemen, place your fingers on the control buttons and press number one. Allow a count of five seconds to pass, then press number two and repeat the operation until after number three has been pressed. Ready! Press number one!"

A faint throbbing surged through the ten men as they simultaneously pressed the first button. The laboratory went aglow with the pale blue luminosity. Then the throbbing intensified, whirring like the wings of a honeybee. To an observer the men might have appeared to vanish slowly from the room in a thin vapor of blue. The electronic current played around them in a shimmering curtain, the electrodes pressing against their flesh creating a slight burning sensation. Their muscles seemed to jerk as the vibrations intensified. As they pressed the third button the throbbing became a high-pitched whine, rising in tone until it almost screamed.

Each man felt a sinister dizziness as he left the laboratory. After a moment of nausea and the sensation of falling into an abysmal pit, they felt no other reaction to the rapid vibrations of the apparatus. But the current continued to whine, sending the oscillations throughout their bodies and weapons with unceasing force. Gradually the weird, spectral world of the Fifth Dimension unfolded itself before them. From their eye-instruments shot twin jets of violet light, that seemed to illuminate a jumbled mass before them. Slowly the terrain of the Fifth Dimension assumed definite shape. It was a rolling, uneven world, covered with a tall violet lush and spectral forests of deep blue. No tall mountains were visible; rather was the Fifth Dimension a place of undulating hills, rolling and rippling as far as they could see.

Just rimming the horizon stood a ball of violet flame. Mortenson knew it was the sun, but he was not certain if it was rising or setting. Its heat made them uncomfortable, for it seemed to bite into them like acid at first. Gradually, as the strange world became clearly defined, they grew accustomed to the force of the violet disk and after a few moments it had risen above the horizon. They had entered the Fifth Dimension at sun rise! On their own world it was well past noon.

Tensed almost to the snapping point, each of the ten men stared about them in search of the horrible creatures Mortenson had told Steckel existed there. Suddenly they discovered that they were actually standing in swaying lush that reached to their shoulders. This came upon them as their eyes began to observe their immediate vicinity. The sudden change of environment had caused them a mild far-sightedness, but now they could see clearly on every side. The lush rolled and swayed like a sea of earthly wheat-stalks in a light breeze.

Mortenson realized in a moment that they would have to mark the spot or their inevitable wanderings would cause them to become hopelessly lost. He yanked his kerchief from a pocket and tied it like a flag to a tuft of the taller plants. It waved feebly in a cool breeze. He turned to Chief Steckel.

"I think it best that we string out in a line, Steckel," he said, his voice sounding microscopically low. "We ought to come upon the phantom bandit's trail in this vicinity. But be careful! He must be desperate and will shoot on sight."

Steckel gave his curt orders. The officers stretched out in a long line. The chief and Mortenson went forward side-by-side with Barton and Riley flanking them. The line swung gradually in a circle around the scientist's handkerchief which acted as a centre. The lush seemed unbroken, being so closely grown together that even a small animal would have left visible indications of its passing through it. They continued onward until suddenly the officers at the far end of the line emitted a triumphant yell. Immediately the others surrounded him to find the lush broken in a narrow path through which the desperado had gone. Feet had trampled down one spot. The trail led away from it. The trampled lush in the one place gave them the impression that the man had popped up out of the yielding soil to go marching away.

Barton suddenly stooped over to pick up an object. He handed it to Chief Steckel. It was a black-tipped matchstick.

"We're on his trail, chief," he said excitedly. "He lit a smoke here and tossed the match at his feet!"

Steckel gave a sibilant whistle. "Damned if we haven't traced the snake to his hole!" he snapped. "I hadn't much stock in this scheme, but it looks like his trail, all right. Let's follow it, strung out. He might be hiding in the grass and a line will bring him out."

He started forward rapidly, eagerly. Mortenson grasped his arm.

"Not so fast, Steckel," he warned ominously. "We're not in our own world, but in one unknown. This tall lush might harbor anything. I have no stomach for running into a wandering band of Fifth Dimensional beings."

Steckel fell back instantly. With Mortenson beside him he followed the trail, the others strung out on either side. Slowly they went on for what seemed hours. It was hard work for them to go through the lush. It was as tough and fibrous as dried coconut husks. Had it not been for their heavy clothing they would have been cut to shreds in no time. Their hands suffered from the ordeal, but it could not be helped. They had not prepared for such conditions and it was too late to go back. They were at last on the trail of the phantom killer. Only death or inconceivable terror could drive them from it. The man must be apprehended at any cost and each had secretly resolved to see the thing through to a finish. Yet they derived a certain sense of pride from the fact that they were among the first humans ever to tread this strange, blue-tinted world. Police history would long remember them for their daring.

Suddenly there was a violent commotion in the lush not far ahead. Abruptly the intrepid man-hunters halted in their tracks. Machine guns were snapped forward. Then a terrifying shriek rent the stillness. Mortenson's blood chilled and he crouched instinctively. The others did likewise from natural instinct, weapons aimed straight ahead to sweep the wall of vegetation with a deadly fire.

For a moment thereafter the place was as silent as a tomb. Then another shriek came from ahead. Tensely the men waited and then the thing appeared, head and shoulders above the swaying, rolling sea of lush. Barton let out a feverish yell and snapped up his gun. It rattled with a staccato snap. The men stood erect to see an incredible monstrosity staring at them through a triangle of eyes that seemed to spit blue flame.

The monster of the Fifth Dimension was like an awful nightmare. It had a long, reptilian neck, at the end of which was a venomous-looking head. Its eyes, as large as saucers, were deep set in the forehead, like the three corners of a triangle. From its neck spurted streams of greenish-blue liquid, spilling through the wounds made by Barton's missiles. The enormous head was studded with unnumbered horns and waved back and forth, a long, purple tongue darting from between fang-filled jaws. With a sudden lunge the beast moved toward the men.

"Shoot!" Steckel bellowed, aghast. "Don't stand there like a squad of statues! Shoot!"

The machine guns went into action with an ominous deadliness. The first barrage literally clipped the monster's head from its body. The beast leaped high in the air and fell with a thud, to writhe in the throes of agony and death. Its long, reptilian tail lashed out, beating madly. Finally the creature lay still and the men went cautiously toward it.

The beast had the legs of a centipede, but thick and powerful. The feet were four-toed and savagely clawed. Mortenson was astounded to find a cross between the reptile and the insect and he promptly named it a _serpenta insecteana_.

With a shudder he turned away. The grim-faced man-hunters continued to follow the trail, wondering silently how the phantom bandit had managed to escape the terrifying beast. But the man had had at least a half-hour start on them and Mortenson concluded that the creature had just happened along.

Mile after mile they plodded on, gripping their guns. The phantom bandit, it seemed, had covered mileage at a rapid rate. Finally they entered into a large clearing at the edge of a spectral forest. Weird trees with thick, leafless branches stood before them, but in the clearing they found traces of a fire. The coals were dead and cold.

"The bandit must have stopped here several days ago," said Mortenson to Steckel. "I think he went on into the forest this day. Let's look for the trail at the edge of the trees."

They discovered the trail quickly. It continued onward through an aisle of trees. They followed it single-file now, for the growths were too thick to be penetrated on the sides. The path seemed to be well-beaten but almost every step of the fleeing desperado was marked by the outline of his heels in the yielding soil.

There were other tracks too, that interested Mortenson, causing him considerable apprehension. The foot-marks of the Fifth Dimension dwellers were clearly defined on the trail. The marks were broad, disclosing the outlines of feet that were like those of a monster goose.

Eventually they emerged from the forest. It proved to be merely a mile-wide belt of trees. Now they found themselves in the tall lush again. The trail continued through it. The lush was well-trampled now as though a large party of men had gone through.

After another hour of steady walking, they encountered a series of trails branching from the main path. They paused, baffled.

"Looks like we're getting near some town or encampment, Mortenson," Steckel suggested. "Do you think the desperado could have gone on ahead to mingle with the creatures you say exist here?"

"That," said the scientist blankly, "I cannot answer. It is hard to believe, however, that any human could stand on friendly terms with such savage, such grotesque beings. The ones I beheld were indeed savage, though my imagination might have made them more so than they are."

Steckel spat at a large, gargantuan beetle that ambled across the trail. "Which one of these trails do you think we ought to follow?" he asked bluntly.

"I'd follow the center one," said Mortenson, studying the trail closely. "Look! There's a heel print."

VI

_Trapped_

Doggedly they went on. Here and there the man's foot-prints showed clearly, but the others were likewise defined. Mortenson wondered if the band had been finally captured, and was being taken now to some Fifth Dimension village. But his thoughts were diverted suddenly, when the men before him halted. They had come upon another clearing, one that sloped down the side of a rolling hill. Well-worn paths criss-crossed it and in the center stood a squalid town with primitive shacks, closely packed together. Off to the left browsed a score or more of strange beasts. Mortenson squinted at them. They were of the same species as was the one which their bullets had destroyed back in the sea of lush! As though sensing the strange visitors, the beasts lifted their heads, eyed them for a moment, and then ambled away.

Something suddenly whined past Steckel's face. It was followed by the dull report of a gun. Instinctively they dodged back out of sight. Steckel looked at Mortenson. His face was white and bloodless.

"He's in that town, Mortenson!" he cried. "He's there!"

"Undoubtedly," replied the scientist, gripping his automatic tightly. "He took a pot shot at us. I saw a wisp of smoke from one of the shacks!"

"Then we've got a fight on our hands, chief," said Barton grimly. "And he's got friends. Let's rush...."

A bullet clipped a blade of lush beside his face and he flattened himself. Then came another report. Barton lined his machine gun on the town, but Mortenson held his arm.

"Don't waste bullets, Barton," he advised. "Wait until you see something to shoot at; then let 'em have it."

That _something_ was soon to appear, for hardly had Mortenson finished giving his warning to Barton than a score of the strange beasts raced from the back of the town and galloped toward them. Running like mammoth centipedes, reptilian heads high, long tails dragging behind them, they came. The men watched, awe-struck. Then a yell from Mortenson broke the spell of awe, that had held them motionless.

"Here they come!" he bellowed, snapping up his automatic. "Look on their backs!"

On each beast rode two or more Fifth Dimension dwellers. They held primitive bows in their hands and had quivers of arrows hanging across their backs. They looked almost human, astride the racing beasts, their long, skinny legs dangling, equally thin arms of which there were four to each creature, waving above their grotesque, egg-shaped heads. They were dwarfed by the size of the monstrous mounts which needed no urging. As they neared the astonished man-hunters, they appeared all arms and legs. Their bodies, blue in color, were short and thick, like the fat belly of a great ape. Their eyes protruded from their faces and waved like the feelers of a snail. And they were equally as loathsome.

"Good God, Mortenson!" Steckel groaned. "We're out-numbered fifteen to one!"

The scientist shuddered, his eyes bulging with terror. "We can't lie here and let them run us down!" he mumbled tensely. "Order your men to shoot their mounts! That'll stop them for the present!"

Steckel stood up impulsively. His head and shoulders rose above the lush. His men lay around him, watching the approaching horde through the vegetation. Before he could give an order, something tugged at his sleeve. A dull report followed and a wisp of white smoke floated from the back of one of the running monsters. Steckel sank with a groan, his left arm feeling numb.

"He got me!" he said dismally. "The killer!"

"Hurt bad, Chief?" Barton quizzed, excitedly.

Steckel shook his head. "Creased me, Barton," he replied. Then he yelled at his men. Instantly the lush at the edge of the clearing became a hornet's nest. The machine guns rattled dully. Mortenson's pistol cracked and his target pitched to the ground. A half-dozen beasts reared up, screamed hideously, and rolled over, spilling their riders headlong. The latter dodged behind the prostrate beasts and showered the ambushers with a hail of arrows.

A shaft buried itself in Riley's chest. He emitted a shrill death cry and rolled over, clutching frenziedly at the arrow. Steckel picked up the detective's machine gun and sent death into more of the running beasts. But there was no halting their mad rush. They continued on toward the men in the lush and the creatures on their backs were either tremendously courageous or too stupid to sense their own danger. They stuck to their mounts until they fell. The clearing was littered with dead and dying. Then the last of the beasts went down under a solid barrage of bullets from the machine guns. It was literally torn to pieces. The riders were buried under it as it rolled over on its back.

Mortenson had a glimpse of a human being running back toward the town. Instantly his automatic went up, but Mortenson had never been a marksman. He emptied his gun at the fleeing desperado and groaned as the man vanished from view. He turned quickly to Steckel. The chief was shooting wildly at the dead beasts hoping to down some of the hideous creatures shielded behind them.

"Steckel!" Mortenson called to attract his attention. The chief looked around, quizzically. "The bandit just ran into a shack to the left," the scientist continued. "I saw him! He didn't have on his Fifth Dimensional apparatus! We've got to get him before he puts it on and vanishes back to our own world! What do you say we rush the town?"