Randall Garrett

What is desirable is not always necessary, while that which is necessary may be most undesirable. Perhaps the measure of a man is the ability to tell one from the other ... and act on it.

Alfred Pendray pushed himself along the corridor of the battleship Shane, holding the flashlight in one hand and using the other hand and his good leg to guide and propel himself by. The beam of the torch reflected queerly from the pastel green walls of the corridor, giving him the uneasy sensation that he was swimming underwater instead of moving through the blasted hulk of a battleship, a thousand light-years from home.

He came to the turn in the corridor, and tried to move to the right, but his momentum was greater than he had thought, and he had to grab the corner of the wall to keep from going on by. That swung him around, and his sprained ankle slammed agonizingly against the other side of the passageway.

Pendray clenched his teeth and kept going. But as he moved down the side passage, he went more slowly, so that the friction of his palm against the wall could be used as a brake.

He wasn't used to maneuvering without gravity; he'd been taught it in Cadets, of course, but that was years ago and parsecs away. When the pseudograv generators had gone out, he'd retched all over the place, but now his stomach was empty, and the nausea had gone.

He had automatically oriented himself in the corridors so that the doors of the various compartments were to his left and right, with the ceiling "above" and the deck "below." Otherwise, he might have lost his sense of direction completely in the complex maze of the interstellar battleship.

Or, he corrected himself, what's left of a battleship.

And what was left? Just Al Pendray and less than half of the once-mighty Shane.

The door to the lifeboat hold loomed ahead in the beam of the flashlight, and Pendray braked himself to a stop. He just looked at the dogged port for a few seconds.

Let there be a boat in there, he thought. Just a boat, that's all I ask. And air, he added as an afterthought. Then his hand went out to the dog handle and turned.

The door cracked easily. There was air on the other side. Pendray breathed a sigh of relief, braced his good foot against the wall, and pulled the door open.

The little lifeboat was there, nestled tightly in her cradle. For the first time since the Shane had been hit, Pendray's face broke into a broad smile. The fear that had been within him faded a little, and the darkness of the crippled ship seemed to be lessened.

Then the beam of his torch caught the little red tag on the air lock of the lifeboat. Repair Work Under Way—Do Not Remove This Tag Without Proper Authority.

That explained why the lifeboat hadn't been used by the other crewmen.

Pendray's mind was numb as he opened the air lock of the small craft. He didn't even attempt to think. All he wanted was to see exactly how the vessel had been disabled by the repair crew. He went inside.

The lights were working in the lifeboat. That showed that its power was still functioning. He glanced over the instrument-and-control panels. No red tags on them, at least. Just to make sure, he opened them up, one by one, and looked inside. Nothing wrong, apparently.

Maybe it had just been some minor repair—a broken lighting switch or something. But he didn't dare hope yet.

He went through the door in the tiny cabin that led to the engine compartment, and he saw what the trouble was.

The shielding had been removed from the atomic motors.

He just hung there in the air, not moving. His lean, dark face remained expressionless, but tears welled up in his eyes and spilled over, spreading their dampness over his lids.

The motors would run, all right. The ship could take him to Earth. But the radiation leakage from those motors would kill him long before he made it home. It would take ten days to make it back to base, and twenty-four hours of exposure to the deadly radiation from those engines would be enough to insure his death from radiation sickness.

His eyes were blurring from the film of tears that covered them; without gravity to move the liquid, it just pooled there, distorting his vision. He blinked the tears away, then wiped his face with his free hand.

Now what?

He was the only man left alive on the Shane, and none of the lifeboats had escaped. The Rat cruisers had seen to that.

They weren't really rats, those people. Not literally. They looked humanoid enough to enable plastic surgeons to disguise a human being as one of them, although it meant sacrificing the little fingers and little toes to imitate the four-digited Rats. The Rats were at a disadvantage there; they couldn't add any fingers. But the Rats had other advantages—they bred and fought like, well, like rats.

Not that human beings couldn't equal them or even surpass them in ferocity, if necessary. But the Rats had nearly a thousand years of progress over Earth. Their Industrial Revolution had occurred while the Angles and the Saxons and the Jutes were pushing the Britons into Wales. They had put their first artificial satellites into orbit while King Alfred the Great was fighting off the Danes.

They hadn't developed as rapidly as Man had. It took them roughly twice as long to go from one step to the next, so that their actual superiority was only a matter of five hundred years, and Man was catching up rapidly. Unfortunately, Man hadn't caught up yet.

The first meeting of the two races had taken place in interstellar space, and had seemed friendly enough. Two ships had come within detector distance of each other, and had circled warily. It was almost a perfect example of the Leinster Hypothesis; neither knew where the other's home world was located, and neither could go back home for fear that the other would be able to follow. But the Leinster Hypothesis couldn't be followed to the end. Leinster's solution had been to have the parties trade ships and go home, but that only works when the two civilizations are fairly close in technological development. The Rats certainly weren't going to trade their ship for the inferior craft of the Earthmen.

The Rats, conscious of their superiority, had a simpler solution. They were certain, after a while, that Earth posed no threat to them, so they invited the Earth ship to follow them home.

The Earthmen had been taken on a carefully conducted tour of the Rats' home planet, and the captain of the Earth ship—who had gone down in history as "Sucker" Johnston—was convinced that the Rats meant no harm, and agreed to lead a Rat ship back to Earth. If the Rats had struck then, there would never have been a Rat-Human War. It would have been over before it started.

But the Rats were too proud of their superiority. Earth was too far away to bother them for the moment; it wasn't in their line of conquest just yet. In another fifty years, the planet would be ready for picking off.

Earth had no idea that the Rats were so widespread. They had taken and colonized over thirty planets, completely destroying the indigenous intelligent races that had existed on five of them.

It wasn't just pride that had made the Rats decide to wait before hitting Earth; there was a certain amount of prudence, too. None of the other races they had met had developed space travel; the Earthmen might be a little tougher to beat. Not that there was any doubt of the outcome, as far as they were concerned—but why take chances?

But, while the Rats had fooled "Sucker" Johnston and some of his officers, the majority of the crew knew better. Rat crewmen were little short of slaves, and the Rats made the mistake of assuming that the Earth crewmen were the same. They hadn't tried to impress the crewmen as they had the officers. When the interrogation officers on Earth questioned the crew of the Earth ship, they, too, became suspicious. Johnston's optimistic attitude just didn't jibe with the facts.

So, while the Rat officers were having the red carpet rolled out for them, Earth Intelligence went to work. Several presumably awe-stricken men were allowed to take a conducted tour of the Rat ship. After all, why not? The Twentieth Century Russians probably wouldn't have minded showing their rocket plants to an American of Captain John Smith's time, either.

But there's a difference. Earth's government knew Earth was being threatened, and they knew they had to get as many facts as they could. They were also aware of the fact that if you know a thing can be done, then you will eventually find a way to do it.

During the next fifty years, Earth learned more than it had during the previous hundred. The race expanded, secretly, moving out to other planets in that sector of the galaxy. And they worked to catch up with the Rats.

They didn't make it, of course. When, after fifty years of presumably peaceful—but highly limited—contact, the Rats hit Earth, they found out one thing. That the mass and energy of a planet armed with the proper weapons can not be out-classed by any conceivable concentration of spaceships.

Throwing rocks at an army armed with machine guns may seem futile, but if you hit them with an avalanche, they'll go under. The Rats lost three-quarters of their fleet to planet-based guns and had to go home to bandage their wounds.

The only trouble was that Earth couldn't counterattack. Their ships were still out-classed by those of the Rats. And the Rats, their racial pride badly stung, were determined to wipe out Man, to erase the stain on their honor wherever Man could be found. Somehow, some way, they must destroy Earth.

And now, Al Pendray thought bitterly, they would do it.

The Shane had sneaked in past Rat patrols to pick up a spy on one of the outlying Rat planets, a man who'd spent five years playing the part of a Rat slave, trying to get information on their activities there. And he had had one vital bit of knowledge. He'd found it and held on to it for over three years, until the time came for the rendezvous.

The rendezvous had almost come too late. The Rats had developed a device that could make a star temporarily unstable, and they were ready to use it on Sol.

The Shane had managed to get off-planet with the spy, but they'd been spotted in spite of the detector nullifiers that Earth had developed. They'd been jumped by Rat cruisers and blasted by the superior Rat weapons. The lifeboats had been picked out of space, one by one, as the crew tried to get away.

In a way, Alfred Pendray was lucky. He'd been in the sick bay with a sprained ankle when the Rats hit, sitting in the X-ray room. The shot that had knocked out the port engine had knocked him unconscious, but the shielded walls of the X-ray room had saved him from the blast of radiation that had cut down the crew in the rear of the ship. He'd come to in time to see the Rat cruisers cut up the lifeboats before they could get well away from the ship. They'd taken a couple of parting shots at the dead hulk, and then left it to drift in space—and leaving one man alive.

In the small section near the rear of the ship, there were still compartments that were airtight. At least, Pendray decided, there was enough air to keep him alive for a while. If only he could get a little power into the ship, he could get the rear air purifiers to working.

He left the lifeboat and closed the door behind him. There was no point in worrying about a boat he couldn't use.

He made his way back toward the engine room. Maybe there was something salvageable there. Swimming through the corridors was becoming easier with practice; his Cadet training was coming back to him.

Then he got a shock that almost made him faint. The beam of his light had fallen full on the face of a Rat. It took him several seconds to realize that the Rat was dead, and several more to realize that it wasn't a Rat at all. It was the spy they had been sent to pick up. He'd been in the sick bay for treatments of the ulcers on his back gained from five years of frequent lashings as a Rat slave.

Pendray went closer and looked him over. He was still wearing the clothing he'd had on when the Shane picked him up.

Poor guy, Pendray thought. All that hell—for nothing.

Then he went around the corpse and continued toward the engine room.

The place was still hot, but it was thermal heat, not radioactivity. A dead atomic engine doesn't leave any residual effects.

Five out of the six engines were utterly ruined, but the sixth seemed to be in working condition. Even the shielding was intact. Again, hope rose in Alfred Pendray's mind. If only there were tools!

A half hour's search killed that idea. There were no tools aboard capable of cutting through the hard shielding. He couldn't use it to shield the engine on the lifeboat. And the shielding that been on the other five engines had melted and run; it was worthless.

Then another idea hit him. Would the remaining engine work at all? Could it be fixed? It was the only hope he had left.

Apparently, the only thing wrong with it was the exciter circuit leads, which had been sheared off by a bit of flying metal. The engine had simply stopped instead of exploding. That ought to be fixable. He could try; it was something to do, anyway.

It took him the better part of two days, according to his watch. There were plenty of smaller tools around for the job, although many of them were scattered and some had been ruined by the explosions. Replacement parts were harder to find, but he managed to pirate some of them from the ruined engines.

He ate and slept as he felt the need. There was plenty of food in the sick bay kitchen, and there is no need for a bed under gravity-less conditions.

After the engine was repaired, he set about getting the rest of the ship ready to move—if it would move. The hull was still solid, so the infraspace field should function. The air purifiers had to be reconnected and repaired in a couple of places. The lights ditto. The biggest job was checking all the broken leads to make sure there weren't any short circuits anywhere.

The pseudogravity circuits were hopeless. He'd have to do without gravity.

On the third day, he decided he'd better clean the place up. There were several corpses floating around, and they were beginning to be noticeable. He had to tow them, one by one, to the rear starboard air lock and seal them between the inner and outer doors. He couldn't dump them, since the outer door was partially melted and welded shut.

He took the personal effects from the men. If he ever got back to Earth, their next-of-kin might want the stuff. On the body of the imitation Rat, he found a belt-pouch full of microfilm. The report on the Rats' new weapon? Possibly. He'd have to look it over later.

On the "morning" of the fourth day, he started the single remaining engine. The infraspace field came on, and the ship began moving at multiples of the speed of light. Pendray grinned. Half gone, will travel, he thought gleefully.

If Pendray had had any liquor aboard, he would have gotten mildly drunk. Instead, he sat down and read the spools of microfilm, using the projector in the sick bay.

He was not a scientist in the strict sense of the word. He was a navigator and a fairly good engineer. So it didn't surprise him any that he couldn't understand a lot of the report. The mechanics of making a semi-nova out of a normal star were more than a little bit over his head. He'd read a little and then go out and take a look at the stars, checking their movement so that he could make an estimate of his speed. He'd jury-rigged a kind of control on the hull field, so he could aim the hulk easily enough. He'd only have to get within signaling range, anyway. An Earth ship would pick him up.

If there was any Earth left by the time he got there.

He forced his mind away from thinking about that.

It was not until he reached the last spool of microfilm that his situation was forcibly brought to focus in his mind. Thus far, he had thought only about saving himself. But the note at the end of the spool made him realize that there were others to save.

The note said: These reports must reach Earth before 22 June 2287. After that, it will be too late.

22 June!

That was—let's see....

This is the eighteenth of September, he thought, June of next year is—nine months away. Surely I can make it in that time. I've got to.

The only question was, how fast was the hulk of the Shane moving?

It took him three days to get the answer accurately. He knew the strength of the field around the ship, and he knew the approximate thrust of the single engine by that time. He had also measured the motions of some of the nearer stars. Thank heaven he was a navigator and not a mechanic or something! At least he knew the direction and distance to Earth, and he knew the distance of the brighter stars from where the ship was.

He had two checks to use, then. Star motion against engine thrust and field strength. He checked them. And rechecked them. And hated the answer.

He would arrive in the vicinity of Sol some time in late July—a full month too late.

What could he do? Increase the output of the engine? No. It was doing the best it could now. Even shutting off the lights wouldn't help anything; they were a microscopic drain on that engine.

He tried to think, tried to reason out a solution, but nothing would come. He found time to curse the fool who had decided the shielding on the lifeboat would have to be removed and repaired. That little craft, with its lighter mass and more powerful field concentration, could make the trip in ten days.

The only trouble was that ten days in that radiation hell would be impossible. He'd be a very well-preserved corpse in half that time, and there'd be no one aboard to guide her.

Maybe he could get one of the other engines going! Sure. He must be able to get one more going, somehow. Anything to cut down on that time!

He went back to the engines again, looking them over carefully. He went over them again. Not a single one could be repaired at all.

Then he rechecked his velocity figures, hoping against hope that he'd made a mistake somewhere, dropped a decimal point or forgotten to divide by two. Anything. Anything!

But there was nothing. His figures had been accurate the first time.

For a while, he just gave up. All he could think of was the terrible blaze of heat that would wipe out Earth when the Rats set off the sun. Man might survive. There were colonies that the Rats didn't know about. But they'd find them eventually. Without Earth, the race would be set back five hundred—maybe five thousand—years. The Rats would would have plenty of time to hunt them out and destroy them.

And then he forced his mind away from that train of thought. There had to be a way to get there on time. Something in the back of his mind told him that there was a way.

He had to think. Really think.

On 7 June 2287, a signal officer on the Earth destroyer Muldoon picked up a faint signal coming from the general direction of the constellation of Sagittarius. It was the standard emergency signal for distress. The broadcaster only had a very short range, so the source couldn't be too far away.

He made his report to the ship's captain. "We're within easy range of her, sir," he finished. "Shall we pick her up?"

"Might be a Rat trick," said the captain. "But we'll have to take the chance. Beam a call to Earth, and let's go out there dead slow. If the detectors show anything funny, we turn tail and run. We're in no position to fight a Rat ship."

"You think this might be a Rat trap, sir?"

The captain grinned. "If you are referring to the Muldoon as a rat trap, Mr. Blake, you're both disrespectful and correct. That's why we're going to run if we see anything funny. This ship is already obsolete by our standards; you can imagine what it is by theirs." He paused. "Get that call in to Earth. Tell 'em this ship is using a distress signal that was obsolete six months ago. And tell 'em we're going out."

"Yes, sir," said the signal officer.

It wasn't a trap. As the Muldoon approached the source of the signal, their detectors picked up the ship itself. It was a standard lifeboat from a battleship of the Shannon class.

"You don't suppose that's from the Shane, do you?" the captain said softly as he looked at the plate. "She's the only ship of that class that's missing. But if that's a Shane lifeboat, what took her so long to get here?"

"She's cut her engines, sir!" said the observer. "She evidently knows we're coming."

"All right. Pull her in as soon as we're close enough. Put her in Number Two lifeboat rack; it's empty."

When the door of the lifeboat opened, the captain of the Muldoon was waiting outside the lifeboat rack. He didn't know exactly what he had expected to see, but it somehow seemed fitting that a lean, bearded man in a badly worn uniform and a haggard look about him should step out.

The specter saluted. "Lieutenant Alfred Pendray, of the Shane," he said, in a voice that had almost no strength. He held up a pouch. "Microfilm," he said. "Must get to Earth immediately. No delay. Hurry."

"Catch him!" the captain shouted. "He's falling!" But one of the men nearby had already caught him.

In the sick bay, Pendray came to again. The captain's questioning gradually got the story out of Pendray.

"... So I didn't know what to do then," he said, his voice a breathy whisper. "I knew I had to get that stuff home. Somehow."

"Go on," said the captain, frowning.

"Simple matter," said Pendray. "Nothing to it. Two equations. Little ship goes thirty times as fast as big ship—big hulk. Had to get here before 22 June. Had to. Only way out, y'unnerstand.

"Anyway. Two equations. Simple. Work 'em in your head. Big ship takes ten months, little one takes ten days. But can't stay in a little ship ten days. No shielding. Be dead before you got here. See?"

"I see," said the captain patiently.

"But—and here's a 'mportant point: If you stay on the big ship for eight an' a half months, then y' only got to be in the little ship for a day an' a half to get here. Man can live that long, even under that radiation. See?" And with that, he closed his eyes.

"Do you mean you exposed yourself to the full leakage radiation from a lifeboat engine for thirty-six hours?"

But there was no answer.

"Let him sleep," said the ship's doctor. "If he wakes up again, I'll let you know. But he might not be very lucid from here on in."

"Is there anything you can do?" the captain asked.

"No. Not after a radiation dosage like that." He looked down at Pendray. "His problem was easy, mathematically. But not psychologically. That took real guts to solve."

"Yeah," said the captain gently. "All he had to do was get here alive. The problem said nothing about his staying that way."