"I'm awake,” came a voice behind them, and they turned.
Thorn came into the control-room, rubbing his eyes. Then he peered tautly through the broad window that framed a magnificent vista of black space and stars.
"What about the cruisers on our tail?” he asked quickly.
The big Mercurian shrugged. “They're hanging on — we've heard their audio calls. And they've called up every Alliance cruiser in this part of the system. We've stirred up a hornets’ nest this time, John!"
John Thorn cut in the switch of the audio. From the speaker came a weird jumble of meaningless sound. All naval calls were always “scrambled” to prevent eavesdropping; only an official unscrambler could translate them.
There was such an unscrambler in this little ship. Thorn had built it, out of his own naval experience. He hastily snapped it on, and the incoherent jumble of sounds from the speaker at once became a crisp, understandable voice.
"— our auras, which shows that present course of the fugitives is straight toward the Zone. Undoubtedly they're hoping to hide out there. It is imperative that we cut them off before they enter the Zone. Flagship Gull, signing off."
"The Gull!" Thorn exclaimed, his brown face strange for a moment. “I know that ship. It was old Commander Leigh speaking. He commands the Alliance patrol squadrons out here."
His thoughts swept him back into memory for a moment. He had, only four years before, commanded a cruiser of the Earth Navy that helped patrol this very sector of space, out here beyond the orbit of Mars, against a surprise League attack.
"They've guessed that we're making for the Zone,” Thorn went on. “It's where all outlaws head for when things get too hot for them."
"The whole system is too hot for us right now,” observed Sual Av. “You should have heard the audio news bulletins going back and forth while you were sleeping. Three Planeteers try to kidnap Earth Chairman! Notorious outlaws foiled in daring attempt.’ The system's ringing with it!"
"It'll ring with the news if we're gunned out of space by those cruisers converging on us,” grunted Gunner Welk sourly. “Do you think we can slip through them, John?"
"I think so,” Thorn clipped. “We've got to keep straight on. Turkoon, the asteroid that's the pirates’ main base, lies in the part of the Zone almost directly ahead."
Thorn stared with narrowed eyes through the broad window, into the magnificent star-flecked vault.
The little ship of the Planeteers was roaring out through the void at top speed, millions of miles outside the orbit of Mars. The bright, small disk of the sun was dead astern, its rays hiding the gray blob of Earth, away from which they had been fleeing for so many long hours.
Ahead of them, the void was thick with bright stars. Brilliant among them gleamed the big yellow topaz of Saturn, and beyond, and to the left, the fainter green sparks of Uranus and Neptune. Pluto was somewhere farther away, off to the right. And Erebus, their mysterious, ultimate goal, lay invisible still farther off — the dark, enigmatic outpost of the solar system.
Directly ahead of the racing little ship, only a few million miles away, extended a wide band of countless tiny specks of light, stretching parallel with the equator of the system. That broad band of light-specks was the Zone, the great asteroidal belt whirling between the orbits of Mars and Jupiter.
Thorn gazed tautly into the Zone. That mighty wilderness of countless planetoids and meteor-swarms, which all ordinary shipping avoided by running above or below, was the No Man's Land of the Solar System. In it the space pirates had long had their lairs, from which they still sallied forth to levy ton on the interplanetary shipping. Countless naval expeditions had tried to clean the place out, and had been baffled by the shifting swarms of meteors and tiny planets which made it impossible to conduct organized operations in there without prohibitive losses.
John Thorn's brown hands clenched. In there, in the Zone, at the pirates’ asteroid base, was the girl who alone in the system, held the secret of mysterious Erebus, the secret that would make possible the securing of the precious radite from that far, dark planet. Somehow, that girl's secret must be secured.
"Calling flagship Gull!” suddenly boomed a deep voice from the audio speaker. “Cruiser Tharine, reporting. Our aura shows the Planeteers’ ship four hundred thousand miles from us, eighteen degrees counter-sunwise."
"Orders to Tharine," rapped back Commander Leigh's hard voice swiftly. “Close in before they slip past you into the Zone. Calling cruiser Rantal!"
"Rantal speaking!” came a quick voice.
"Change your course to eighty-six degrees sunwise,” hammered the Commander. “You and the Tharine can catch the Planeteers between you if you put on all speed."
Sual Av scratched his bald head and looked at Thorn. “They're converging on us from two sides, John."
"Damn them!” growled the huge Mercurian angrily. “If they only knew that we Planeteers are risking our necks for the sake of the Alliance—"
"But they don't know. To them, we're outlaws who must be either captured or gunned,” John Thorn clipped. “We've got to outrun those two cruisers! Turn the injectors on full, Gunner."
The Mercurian quickly obeyed. Thorn leaned toward the bank of firing-keys, his eyes on the power gauges.
All modern space ships were propelled by the atomic disintegration of copper or a similar metal. The powdered metal's atoms were broken down by terrific electric voltages, in power chambers of heavy inertrum. Only inertrum, that artificial metal whose atoms were synthetically “crystallized,” could stand the awful strain.
Much of the atomic energy generated in the chambers had to be fed back into them as electric voltage, to continue the process. But there was enough surplus to eject streams of protons at high speed from the inertrum rocket-tubes, propelling the ship.
John Thorn cut in all stern tubes. The little ship jerked forward with the deafening roar of the blast.
"Check the aura-chart,” he ordered Sual Av. “See if we're losing those cruisers."
The Venusian snapped on their ship's aura. The “aura” was a field of electromagnetic vibrations radiated for a million miles in all directions by a projector in the ship. The vibrations were reflected back by any object within that radius of space, and automatically plotted and recorded on the aura-chart.
The chart was a sphere of pale light, poised above the window. At the center of the luminous sphere was a black dot representing their ship. Off to right and left of the black dot moved two red sparks, cutting in obliquely toward them as all advanced.
"They're close — no more than a quarter of a million miles,” reported Sual Av.
"The Zone isn't much farther than that ahead,” Thorn declared.
"But there's a big meteor swarm in the Zone directly ahead of us!” Gunner Welk exclaimed. “We can't run into that!"
In the fore of the aura-chart sphere glimmered a cloud of very tiny crimson flecks, whirling, seething. It was the edge of a great cloud of meteors at the lip of the Zone, stretching across a million miles of space in front of their fleeing little ship.
Thorn could see the swarm in black space ahead. Not the myriad meteors themselves, but a constant winking and flashing of tiny flares, where meteors in the whirling storm of stone struck and fused every few minutes.
"Rantal reporting!” rapped the audio speaker. “Planeteers are now keeping their lead on us, and running straight on toward the Zone."
"Keep after them!” ordered the Commander's grim voice. “Swarm six-sixty-two is just ahead of them and they won't dare enter that. We'll have them boxed."