"I hope _you_ don't have any ideas of----"

Alan clipped off Kandin's sentence before it had gotten fully started.

"I don't need advice, Art. I know what's right and wrong. Tell me the truth--did Dad send you to sound me out?"

Kandin flushed and looked down. "I'm sorry, Alan. I didn't mean--well----"

They fell silent. Alan returned his attention to his breakfast, while Kandin stared moodily off into the distance.

"You know," the First Officer said finally, "I've been thinking about Steve. It just struck me that you can't call him your twin any more.

That's one of the strangest quirks of star travel that's been recorded yet."

"I thought of that. He's twenty-six, I'm seventeen, and yet we used to be twins. But the Fitzgerald Contraction does funny things."

"That's for sure," Kandin said. "Well, time for me to start relaxing."

He clapped Alan on the back, disentangled his long legs from the bench, and was gone.

_The Fitzgerald Contraction does funny things_, Alan repeated to himself, as he methodically chewed his way through the rest of his meal and got on line to bring the dishes to the yawning hopper that would carry them down to the molecular cleansers. _Real funny things._

He tried to picture what Steve looked like now, nine years older. He couldn't.

_As velocity approaches that of light, time approaches zero._

That was the key to the universe. _Time approaches zero._ The crew of a s.p.a.ceship travelling from Earth to Alpha Centauri at a speed close to that of light would hardly notice the pa.s.sage of time on the journey.

It was, of course, impossible ever actually to reach the speed of light.

But the great starships could come close. And the closer they came, the greater the contraction of time aboard ship.

It was all a matter of relativity. Time is relative to the observer.

Thus travel between the stars was possible. Without the Fitzgerald Contraction, the crew of a s.p.a.ceship would age five years en route to Alpha C, eight to Sirius, ten to Procyon. More than two centuries would elapse in pa.s.sage to a far-off star like Bellatrix.

Thanks to the contraction effect, Alpha C was three weeks away, Sirius a month and a half. Even Bellatrix was just a few years' journey distant.

Of course, when the crew returned to Earth they found things completely changed; years had pa.s.sed on Earth, and life had moved on.

Now the _Valhalla_ was back on Earth again for a short stay. On Earth, starmen congregated at the Enclaves, the cities-within-cities that grew up at each s.p.a.ceport. There, starmen mingled in a society of their own, without attempting to enter the confusing world outside.

Sometimes a s.p.a.cer broke away. His ship left him behind, and he became an Earther. Steve Donnell had done that.

_The Fitzgerald Contraction does funny things._ Alan thought of the brother he had last seen just a few weeks ago, young, smiling, his own identical twin--and wondered what the nine extra years had done to him.

_Chapter Two_

Alan dumped his breakfast dishes into the hopper and walked briskly out of the mess hall. His destination was the Central Control Room, that long and broad chamber that was the nerve-center of the ship's activities just as the Common Recreation Room was the center of off-duty socializing for the Crew.

He found the big board where the a.s.signments for the day were chalked, and searched down the long lists for his own name.

"You're working with me today, Alan," a quiet voice said.

He turned at the sound of the voice and saw the short, wiry figure of Dan Kelleher, the cargo chief. He frowned. "I guess we'll be crating from now till tonight without a stop," he said unhappily.

Kelleher shook his head. "Wrong. There's really not very much work. But it's going to be cold going. All those chunks of dinosaur meat in the preserving hold are going to get packed up. It won't be fun."

Alan agreed.

He scanned the board, looking down the rows for the list of cargo crew.

Sure enough, there was his name: _Donnell, Alan_, chalked in under the big double C. As an Unspecialized Crewman he was shifted from post to post, filling in wherever he was needed.

"I figure it'll take four hours to get the whole batch crated," Kelleher said. "You can take some time off now, if you want to. You'll be working to make up for it soon enough."

"I won't debate the point. Suppose I report to you at 0900?"

"Suits me."

"In case you need me before then, I'll be in my cabin. Just ring me."

Once back in his cabin, a square cubicle in the beehive of single men's rooms in the big ship's fore section, Alan unslung his pack and took out the dog-eared book he knew so well. He riffled through its pages. _The Cavour Theory_, it said in worn gold letters on the spine. He had read the volume end-to-end at least a hundred times.

"I still can't see why you're so wild on Cavour," Rat grumbled, looking up from his doll-sized sleeping-cradle in the corner of Alan's cabin.

"If you ever do manage to solve Cavour's equations you're just going to put yourself and your family right out of business. Hand me my nibbling-stick, like a good fellow."

Alan gave Rat the much-gnawed stick of Jovian oak which the Bellatrician used to keep his tiny teeth sharp.

"You don't understand," Alan said. "If we can solve Cavour's work and develop the hyperdrive, we won't be handicapped by the Fitzgerald Contraction. What difference does it make in the long run if the _Valhalla_ becomes obsolete? We can always convert it to the new drive.

The way I see it, if we could only work out the secret of Cavour's hypers.p.a.ce drive, we'd----"

"I've heard it all before," Rat said, with a note of boredom in his reedy voice. "Why, with hypers.p.a.ce drive you'd be able to flit all over the galaxy without suffering the time-lag you experience with regular drive. And then you'd accomplish your pet dream of going everywhere and seeing everything. Ah! Look at the eyes light up! Look at the radiant expression! You get starry-eyed every time you start talking about the hyperdrive!"

Alan opened the book to a dog-eared page. "I know it can be done eventually. I'm sure of it. I'm even sure Cavour himself actually succeeded in building a hypers.p.a.ce vessel."

"Sure," Rat said drily, switching his long tail from side to side. "Sure he built one. That explains his strange disappearance. Went out like a snuffed candle, soon as he turned on his drive. Okay, go ahead and build one--if you can. But don't bother booking pa.s.sage for me."

"You mean you'd stay behind if I built a hypers.p.a.ce ship?"

"Sure I would." There was no hesitation in Rat's voice. "I like this particular s.p.a.ce-time continuum very much. I don't care at all to wind up seventeen dimensions north of here with no way back."

"You're just an old stick-in-the mud." Alan glanced at his wristchron.

It read 0852. "Time for me to get to work. Kelleher and I are packing frozen dinosaur today. Want to come along?"

Rat wiggled the tip of his nose in a negative gesture. "Thanks all the same, but the idea doesn't appeal. It's nice and warm here. Run along, boy; I'm sleepy." He curled up in his cradle, wrapped his tail firmly around his body, and closed his eyes.

There was a line waiting at the entrance to the freezer section, and Alan took his place on it. One by one they climbed into the s.p.a.cesuits which the boy in charge provided, and entered the airlock.

For transporting perishable goods--such as the dinosaur meat brought back from the colony on Alpha C IV to satisfy the heavy demand for that odd-tasting delicacy on Earth--the _Valhalla_ used the most efficient freezing system of all: a compartment which opened out into the vacuum of s.p.a.ce. The meat was packed in huge open receptacles which were flooded just before blastoff; before the meat had any chance to spoil, the lock was opened, the air fled into s.p.a.ce and the compartment's heat radiated outward. The water froze solid, preserving the meat. It was just as efficient as building elaborate refrigeration coils, and a good deal simpler.