At 04 hours 10 minutes, ship time, the Niccola was well inside the Theta Gisol solar system. She had previously secured excellent evidence that this was not the home of the Plumie civilization. There was no tuned radiation. There was no evidence of interplanetary travel--rockets would be more than obvious, and a magnetronic drive had a highly characteristic radiation-pattern--so the real purpose of the Niccola’s voyage would not be accomplished here. She wouldn’t find out where Plumies came from.

There might, though, be one or more of those singular, conical, hollow-topped cairns sheltering silicon-bronze plates, which constituted the evidence that Plumies existed. The Niccola went sunward toward the inner planets to see. Such cairns had been found on conspicuous landmarks on oxygen-type planets over a range of some twelve hundred light-years. By the vegetation about them, some were a century old. On the same evidence, others had been erected only months or weeks or even days before a human Space Survey ship arrived to discover them. And the situation was unpromising. It wasn’t likely that the galaxy was big enough to hold two races of rational beings capable of space travel. Back on ancient Earth, a planet had been too small to hold two races with tools and fire. Historically, that problem was settled when _Homo sapiens exterminated Homo neanderthalis_. It appeared that the same situation had arisen in space. There were humans, and there were Plumies. Both had interstellar ships. To humans, the fact was alarming. The need for knowledge, and the danger that Plumies might know more first, and thereby be able to exterminate humanity, was appalling.

Therefore the Niccola. She drove on sunward. She had left one frozen outer planet far behind. She had crossed the orbits of three others. The last of these was a gas giant with innumerable moonlets revolving about it. It was now some thirty millions of miles back and twenty to one side. The sun, ahead, flared and flamed in emptiness against that expanse of tinted stars.

Jon Baird worked steadily in the Niccola’s radar room. He was one of those who hoped that the Plumies would not prove to be the natural enemies of mankind. Now, it looked like this ship wouldn’t find out in this solar system. There were plenty of other ships on the hunt. From here on, it looked like routine to the next unvisited family of planets. But meanwhile he worked. Opposite him, Diane Holt worked as steadily, her dark head bent intently over a radar graph in formation. The immediate job was the completion of a map of the meteor swarms following cometary orbits about this sun. They interlaced emptiness with hazards to navigation, and nobody would try to drive through a solar system without such a map.

Elsewhere in the ship, everything was normal. The engine room was a place of stillness and peace, save for the almost inaudible hum of the drive, running at half a million Gauss flux-density. The skipper did whatever skippers do when they are invisible to their subordinates. The weapons officer, Taine, thought appropriate thoughts. In the navigation room the second officer conscientiously glanced at each separate instrument at least once in each five minutes, and then carefully surveyed all the screens showing space outside the ship. The stewards disposed of the debris of the last meal, and began to get ready for the next. In the crew’s quarters, those off duty read or worked at scrimshaw, or simply and contentedly loafed.

Diane handed over the transparent radar graph, to be fitted into the three-dimensional map in the making.

“There’s a lump of stuff here,” she said interestedly. “It could be the comet that once followed this orbit, now so old it’s lost all its gases and isn’t a comet any longer.”

At this instant, which was 04 hours 25 minutes ship time, the alarm-bell rang. It clanged stridently over Baird’s head, repeater-gongs sounded all through the ship, and there was a scurrying and a closing of doors. The alarm gong could mean only one thing. It made one’s breath come faster or one’s hair stand on end, according to temperament.

The skipper’s face appeared on the direct-line screen from the navigation room.

“Plumies?“ he demanded harshly. “Mr. Baird! Plumies?“

Baird’s hands were already flipping switches and plugging the radar room apparatus into a new setup.

“There’s a contact, sir,” he said curtly. “No. There was a contact. It’s broken now. Something detected us. We picked up a radar pulse. One.”

The word “one” meant much. A radar system that could get adequate information from a single pulse was not the work of amateurs. It was the product of a very highly developed technology. Setting all equipment to full-globular scanning, Baird felt a certain crawling sensation at the back of his neck. He’d been mapping within a narrow range above and below the line of this system’s ecliptic. A lot could have happened outside the area he’d had under long-distance scanning.

But seconds passed. They seemed like years. The all-globe scanning covered every direction out from the Niccola. Nothing appeared which had not been reported before. The gas-giant planet far behind, and the only inner one on this side of the sun, would return their pulses only after minutes. Meanwhile the radars reported very faintfully, but they only repeated previous reports.

“No new object within half a million miles,” said Baird, after a suitable interval. Presently he added: “Nothing new within three-quarter million miles.” Then: “Nothing new within a million miles...”

The skipper said bitingly:

“Then you’d better check on objects that are not new!“ He turned aside, and his voice came more faintly as he spoke into another microphone. “_Mr. Taine! Arm all rockets and have your tube crews stand by in combat readiness! Engine room! Prepare drive for emergency maneuvers! Damage-control parties, put on pressure suits and take combat posts with equipment!“ His voice rose again in volume. “Mr. Baird! How about observed objects?_”

Diane murmured. Baird said briefly:

“Only one suspicious object, sir--and that shouldn’t be suspicious. We are sending an information-beam at something we’d classed as a burned-out comet. Pulse going out now, sir.”

Diane had the distant-information transmitter aimed at what she’d said might be a dead comet. Baird pressed the button. An extraordinary complex of information-seeking frequencies and forms sprang into being and leaped across emptiness. There were microwaves of strictly standard amplitude, for measurement-standards. There were frequencies of other values, which would be selectively absorbed by this material and that. There were laterally and circularly polarized beams. When they bounced back, they would bring a surprising amount of information.

They returned. They did bring back news. The thing that had registered as a larger lump in a meteor-swarm was not a meteor at all. It returned four different frequencies with a relative-intensity pattern which said that they’d been reflected by bronze--probably silicon bronze. The polarized beams came back depolarized, of course, but with phase-changes which said the reflector had a rounded, regular form. There was a smooth hull of silicon bronze out yonder. There was other data.

“It will be a Plumie ship, sir,” said Baird very steadily. “At a guess, they picked up our mapping beam and shot a single pulse at us to find out who and what we were. For another guess, by now they’ve picked up and analyzed our information-beam and know what we’ve found out about them.”

The skipper scowled.

“How many of them?“ he demanded. “Have we run into a fleet?“

“I’ll check, sir,” said Baird. “We picked up no tuned radiation from outer space, sir, but it could be that they picked us up when we came out of overdrive and stopped all their transmissions until they had us in a trap.”

“Find out how many there are!“ barked the skipper. “_Make it quick! Report additional data instantly!_”

His screen clicked off. Diane, more than a little pale, worked swiftly to plug the radar-room equipment into a highly specialized pattern. The Niccola was very well equipped, radar-wise. She’d been a type G8 Survey ship, and on her last stay in port she’d been rebuilt especially to hunt for and make contact with Plumies. Since the discovery of their existence, that was the most urgent business of the Space Survey. It might well be the most important business of the human race--on which its survival or destruction would depend. Other remodeled ships had gone out before the Niccola, and others would follow until the problem was solved. Meanwhile the Niccola’s twenty-four rocket tubes and stepped-up drive and computer-type radar system equipped her for Plumie-hunting as well as any human ship could be. Still, if she’d been lured deep into the home system of the Plumies, the prospects were not good.

The new setup began its operation, instantly the last contact closed. The three-dimensional map served as a matrix to control it. The information-beam projector swung and flung out its bundle of oscillations. It swung and flashed, and swung and flashed. It had to examine every relatively nearby object for a constitution of silicon bronze and a rounded shape. The nearest objects had to be examined first. Speed was essential. But three-dimensional scanning takes time, even at some hundreds of pulses per minute.

Nevertheless, the information came in. No other silicon-bronze object within a quarter-million miles. Within half a million. A million. A million and a half. Two million...

Baird called the navigation room.

“Looks like a single Plumie ship, sir,” he reported. “At least there’s one ship which is nearest by a very long way.”

“Hah!“ grunted the skipper. “_Then we’ll pay him a visit. Keep an open line, Mr. Baird!“ His voice changed. “Mr. Taine! Report here at once to plan tactics!_”

Baird shook his head, to himself. The Niccola’s orders were to make contact without discovery, if such a thing were possible. The ideal would be a Plumie ship or the Plumie civilization itself, located and subject to complete and overwhelming envelopment by human ships--before the Plumies knew they’d been discovered. And this would be the human ideal because humans have always had to consider that a stranger might be hostile, until he’d proven otherwise.

Such a viewpoint would not be optimism, but caution. Yet caution was necessary. It was because the Survey brass felt the need to prepare for every unfavorable eventuality that Taine had been chosen as weapons officer of the Niccola. His choice had been deliberate, because he was a xenophobe. He had been a problem personality all his life. He had a seemingly congenital fear and hatred of strangers--which in mild cases is common enough, but Taine could not be cured without a complete breakdown of personality. He could not serve on a ship with a multiracial crew, because he was invincibly suspicious of and hostile to all but his own small breed. Yet he seemed ideal for weapons officer on the Niccola, provided he never commanded the ship. Because if the Plumies were hostile, a well-adjusted, normal man would never think as much like them as a Taine. He was capable of the kind of thinking Plumies might practice, if they were xenophobes themselves.

But to Baird, so extreme a precaution as a known psychopathic condition in an officer was less than wholly justified. It was by no means certain that the Plumies would instinctively be hostile. Suspicious, yes. Cautious, certainly. But the only fact known about the Plumie civilization came from the cairns and silicon-bronze inscribed tablets they’d left on oxygen-type worlds over a twelve-hundred-light-year range in space, and the only thing to be deduced about the Plumies themselves came from the decorative, formalized symbols like feathery plumes which were found on all their bronze tablets. The name “Plumies” came from that symbol.

Now, though, Taine was called to the navigation room to confer on tactics. The Niccola swerved and drove toward the object Baird identified as a Plumie ship. This was at 05 hours 10 minutes ship time. The human ship had a definite velocity sunward, of course. The Plumie ship had been concealed by the meteor swarm of a totally unknown comet. It was an excellent way to avoid observation. On the other hand, the Niccola had been mapping, which was bound to attract attention. Now each ship knew of the other’s existence. Since the Niccola had been detected, she had to carry out orders and attempt a contact to gather information.

Baird verified that the Niccola’s course was exact for interception at her full-drive speed. He said in a flat voice:

“I wonder how the Plumies will interpret this change of course? They know we’re aware they’re not a meteorite. But charging at them without even trying to communicate could look ominous. We could be stupid, or too arrogant to think of anything but a fight.” He pressed the skipper’s call and said evenly: “Sir, I request permission to attempt to communicate with the Plumie ship. We’re ordered to try to make friends if we know we’ve been spotted.”

Taine had evidently just reached the navigation room. His voice snapped from the speaker:

“_I advise against that, sir! No use letting them guess our level of technology!_”

Baird said coldly:

“They’ve a good idea already. We beamed them for data.”

There was silence, with only the very faint humming sound which was natural in the ship in motion. It would be deadly to the nerves if there were absolute silence. The skipper grumbled:

“_Requests and advice! Dammit! Mr. Baird, you might wait for orders! But I was about to ask you to try to make contact through signals. Do so._”

His speaker clicked off. Baird said:

“It’s in our laps. Diane. And yet we have to follow orders. Send the first roll.”

Diane had a tape threaded into a transmitter. It began to unroll through a pickup head. She put on headphones. The tape began to transmit toward the Plumie. Back at base it had been reasoned that a pattern of clickings, plainly artificial and plainly stating facts known to both races, would be the most reasonable way to attempt to open contact. The tape sent a series of cardinal numbers--one to five. Then an addition table, from one plus one to five plus five. Then a multiplication table up to five times five. It was not startlingly intellectual information to be sent out in tiny clicks ranging up and down the radio spectrum. But it was orders.

Baird sat with compressed lips. Diane listened for a repetition of any of the transmitted signals, sent back by the Plumie. The speakers about the radar room murmured the orders given through all the ship. Radar had to be informed of all orders and activity, so it could check their results outside the ship. So Baird heard the orders for the engine room to be sealed up and the duty-force to get into pressure suits, in case the Niccola fought and was hulled. Damage-control parties reported themselves on post, in suits, with equipment ready. Then Taine’s voice snapped: “_Rocket crews, arm even-numbered rockets with chemical explosive warheads. Leave odd-numbered rockets armed with atomics. Report back!_”

Diane strained her ears for possible re-transmission of the Niccola’s signals, which would indicate the Plumie’s willingness to try conversation. But she suddenly raised her hand and pointed to the radar-graph instrument. It repeated the positioning of dots which were stray meteoric matter in the space between worlds in this system. What had been a spot--the Plumie ship--was now a line of dots. Baird pressed the button.

“Radar reporting!” he said curtly. “The Plumie ship is heading for us. I’ll have relative velocity in ten seconds.”

He heard the skipper swear. Ten seconds later the Doppler measurement became possible. It said the Plumie plunged toward the Niccola at miles per second. In half a minute it was tens of miles per second. There was no re-transmission of signals. The Plumie ship had found itself discovered. Apparently it considered itself attacked. It flung itself into a headlong dash for the Niccola.

Time passed--interminable time. The sun flared and flamed and writhed in emptiness. The great gas-giant planet rolled through space in splendid state, its moonlets spinning gracefully about its bulk. The oxygen-atmosphere planet to sunward was visible only as a crescent, but the mottlings on its lighted part changed as it revolved--seas and islands and continents receiving the sunlight as it turned. Meteor swarms, so dense in appearance on a radar screen, yet so tenuous in reality, floated in their appointed orbits with a seeming vast leisure.

The feel of slowness was actually the result of distance. Men have always acted upon things close by. Battles have always been fought within eye-range, anyhow. But it was actually 06 hours 35 minutes ship time before the two spacecraft sighted each other--more than two hours after they plunged toward a rendezvous.

The Plumie ship was a bright golden dot, at first. It decelerated swiftly. In minutes it was a rounded, end-on disk. Then it swerved lightly and presented an elliptical broadside to the Niccola. The Niccola was in full deceleration too, by then. The two ships came very nearly to a stop with relation to each other when they were hardly twenty miles apart--which meant great daring on both sides.

Baird heard the skipper grumbling:

“Damned cocky!“ He roared suddenly: “_Mr. Baird! How’ve you made out in communicating with them?_”

“Not at all, sir,” said Baird grimly. “They don’t reply.”

He knew from Diane’s expression that there was no sound in the headphones except the frying noise all main-sequence stars give out, and the infrequent thumping noises that come from gas-giant planets’ lower atmospheres, and the Jansky-radiation hiss which comes from everywhere.

The skipper swore. The Plumie ship lay broadside to, less than a score of miles away. It shone in the sunlight. It acted with extraordinary confidence. It was as if it dared the Niccola to open fire.

Taine’s voice came out of a speaker, harsh and angry:

“Even-numbered tubes prepare to fire on command.“

Nothing happened. The two ships floated sunward together, neither approaching nor retreating. But with every second, the need for action of some sort increased.

“Mr. Baird!“ barked the skipper. “_This is ridiculous! There must be some way to communicate! We can’t sit here glaring at each other forever! Raise them! Get some sort of acknowledgment!_”

“I’m trying,” said Baird bitterly, “according to orders!”

But he disagreed with those orders. It was official theory that arithmetic values, repeated in proper order, would be the way to open conversation. The assumption was that any rational creature would grasp the idea that orderly signals were rational attempts to open communication.

But it had occurred to Baird that a Plumie might not see this point. Perception of order is not necessarily perception of information--in fact, quite the contrary. A message is a disturbance of order. A microphone does not transmit a message when it sends an unvarying tone. A message has to be unpredictable or it conveys no message. Orderly clicks, even if overheard, might seem to Plumies the result of methodically operating machinery. A race capable of interstellar flight was not likely to be interested or thrilled by exercises a human child goes through in kindergarten. They simply wouldn’t seem meaningful at all.

But before he could ask permission to attempt to make talk in a more sophisticated fashion, voices exclaimed all over the ship. They came blurringly to the loud-speakers. “Look at that!“ “What’s he do--“ “Spinning like--“ From every place where there was a vision-plate on the Niccola, men watched the Plumie ship and babbled.

This was at 06 hours 50 minutes ship time.

The elliptical golden object darted into swift and eccentric motion. Lacking an object of known size for comparison, there was no scale. The golden ship might have been the size of an autumn leaf, and in fact its maneuvers suggested the heedless tumblings and scurrying of falling foliage. It fluttered in swift turns and somersaults and spinnings. There were weavings like the purposeful feints of boxers not yet come to battle. There were indescribably graceful swoops and loops and curving dashes like some preposterous dance in emptiness.

Taine’s voice crashed out of a speaker:

“All even-number rockets,” he barked. “Fire!“

[Illustration]

The skipper roared a countermand, but too late. The crunching, grunting sound of rockets leaving their launching tubes came before his first syllable was complete. Then there was silence while the skipper gathered breath for a masterpiece of profanity. But Taine snapped:

“_That dance was a sneak-up! The Plumie came four miles nearer while we watched!_”

Baird jerked his eyes from watching the Plumie. He looked at the master radar. It was faintly blurred with the fading lines of past gyrations, but the golden ship was much nearer the Niccola than it had been.

“Radar reporting,” said Baird sickishly. “Mr. Taine is correct. The Plumie ship did approach us while it danced.”

Taine’s voice snarled:

“_Reload even numbers with chemical-explosive war heads. Then remove atomics from odd numbers and replace with chemicals. The range is too short for atomics._”

Baird felt curiously divided in his own mind. He disliked Taine very much. Taine was arrogant and suspicious and intolerant even on the Niccola. But Taine had been right twice, now. The Plumie ship had crept closer by pure trickery. And it was right to remove atomic war heads from the rockets. They had a pure-blast radius of ten miles. To destroy the Plumie ship within twice that would endanger the Niccola--and leave nothing of the Plumie to examine afterward.

The Plumie ship must have seen the rocket flares, but it continued to dance, coming nearer and ever nearer in seemingly heedless and purposeless plungings and spinnings in star-speckled space. But suddenly there were racing, rushing trails of swirling vapor. Half the Niccola’s port broadside plunged toward the golden ship. The fraction of a second later, the starboard half-dozen chemical-explosive rockets swung furiously around the ship’s hull and streaked after their brothers. They moved in utterly silent, straight-lined, ravening ferocity toward their target. Baird thought irrelevantly of the vapor trails of an atmosphere-liner in the planet’s upper air.

The ruled-line straightness of the first six rockets’ course abruptly broke. One of them veered crazily out of control. It shifted to an almost right-angled course. A second swung wildly to the left. A third and fourth and fifth--The sixth of the first line of rockets made a great, sweeping turn and came hurtling back toward the Niccola. It was like a nightmare. Lunatic, erratic lines of sunlit vapor eeled before the background of all the stars in creation.

Then the second half-dozen rockets broke ranks, as insanely and irremediably as the first.

Taine’s voice screamed out of a speaker, hysterical with fury:

“_Detonate! Detonate! They’ve taken over the rockets and are throwing ‘em back at us! Detonate all rockets!_”

The heavens seemed streaked and laced with lines of expanding smoke. But now one plunging line erupted at its tip. A swelling globe of smoke marked its end. Another blew up. And another--

The Niccola’s rockets faithfully blew themselves to bits on command from the Niccola’s own weapons control. There was nothing else to be done with them. They’d been taken over in flight. They’d been turned and headed back toward their source. They’d have blasted the Niccola to bits but for their premature explosions.

There was a peculiar, stunned hush all through the Niccola. The only sound that came out of any speaker in the radar room was Taine’s voice, high-pitched and raging, mouthing unspeakable hatred of the Plumies, whom no human being had yet seen.

Baird sat tense in the frustrated and desperate composure of the man who can only be of use while he is sitting still and keeping his head. The vision screen was now a blur of writhing mist, lighted by the sun and torn at by emptiness. There was luminosity where the ships had encountered each other. It was sunshine upon thin smoke. It was like the insanely enlarging head of a newborn comet, whose tail would be formed presently by light-pressure. The Plumie ship was almost invisible behind the unsubstantial stuff.

But Baird regarded his radar screens. Microwaves penetrated the mist of rapidly ionizing gases.

“Radar to navigation!” he said sharply. “The Plumie ship is still approaching, dancing as before!”

The skipper said with enormous calm:

“Any other Plumie ships, Mr. Baird?“

Diane interposed.

“No sign anywhere. I’ve been watching. This seems to be the only ship within radar range.”

“We’ve time to settle with it, then,” said the skipper. “_Mr. Taine, the Plumie ship is still approaching._”

Baird found himself hating the Plumies. It was not only that humankind was showing up rather badly, at the moment. It was that the Plumie ship had refused contact and forced a fight. It was that if the Niccola were destroyed the Plumie would carry news of the existence of humanity and of the tactics which worked to defeat them. The Plumies could prepare an irresistible fleet. Humanity could be doomed.

But he overheard himself saying bitterly:

“I wish I’d known this was coming, Diane. I ... wouldn’t have resolved to be strictly official, only, until we got back to base.”

Her eyes widened. She looked startled. Then she softened.

“If ... you mean that ... I wish so too.”

“It looks like they’ve got us,” he admitted unhappily. “If they can take our rockets away from us--” Then his voice stopped. He said, “Hold everything!” and pressed the navigation-room button. He snapped: “Radar to navigation. It appears to take the Plumies several seconds to take over a rocket. They have to aim something--a pressor or tractor beam, most likely--and pick off each rocket separately. Nearly forty seconds was consumed in taking over all twelve of our rockets. At shorter range, with less time available, a rocket might get through!”

The skipper swore briefly. Then:

“_Mr. Taine! When the Plumies are near enough, our rockets may strike before they can be taken over! You follow?_”

Baird heard Taine’s shrill-voiced acknowledgment--in the form of practically chattered orders to his rocket-tube crews. Baird listened, checking the orders against what the situation was as the radars saw it. Taine’s voice was almost unhuman; so filled with frantic rage that it cracked as he spoke. But the problem at hand was the fulfillment of all his psychopathic urges. He commanded the starboard-side rocket-battery to await special orders. Meanwhile the port-side battery would fire two rockets on widely divergent courses, curving to join at the Plumie ship. They’d be seized. They were to be detonated and another port-side rocket fired instantly, followed by a second hidden in the rocket-trail the first would leave behind. Then the starboard side--

“I’m afraid Taine’s our only chance,” said Baird reluctantly. “If he wins, we’ll have time to ... talk as people do who like each other. If it doesn’t work--”

Diane said quietly:

“Anyhow ... I’m glad you ... wanted me to know. I ... wanted you to know, too.”

She smiled at him, yearningly.

There was the crump-crump of two rockets going out together. Then the radar told what happened. The Plumie ship was no more than six miles away, dancing somehow deftly in the light of a yellow sun, with all the cosmos spread out as shining pin points of colored light behind it. The radar reported the dash and the death of the two rockets, after their struggle with invisible things that gripped them. They died when they headed reluctantly back to the Niccola--and detonated two miles from their parent ship. The skipper’s voice came:

“_Mr. Taine! After your next salvo I shall head for the Plumie at full drive, to cut down the distance and the time they have to work in. Be ready!_”

The rocket tubes went crump-crump again, with a fifth of a second interval. The radar showed two tiny specks speeding through space toward the weaving, shifting speck which was the Plumie.

Outside, in emptiness, there was a filmy haze. It was the rocket-fumes and explosive gases spreading with incredible speed. It was thin as gossamer. The Plumie ship undoubtedly spotted the rockets, but it did not try to turn them. It somehow seized them and deflected them, and darted past them toward the Niccola.