me here, and now I'm grown-up.

Tommy grinned at him in the mirror. "What are you going to do, now we've finished our so-called education?"

"What do you think? Go back to Vega with Dad, by Lhari ship, and help him run Vega Interplanet. Why else would I bother with all that astrogation and math?"

"You're the lucky one, with your father owning a dozen ships! He must be almost as rich as the Lhari."

Bart shook his head. "It's not that easy. Space travel inside a system these days is small stuff; all the real travel and shipping goes to the Lhari ships."

It was a sore point with everyone. Thousands of years ago, men had spread out from Earth—first to the planets, then to the nearer stars, crawling in ships that could travel no faster than the speed of light. They had even believed that was an absolute limit—that nothing in the universe could exceed the speed of light. It took years to go from Earth to the nearest star.

But they'd done it. From the nearer stars, they had sent out colonizing ships all through the galaxy. Some vanished and were never heard from again, but some made it, and in a few centuries man had spread all over hundreds of star-systems.

And then man met the people of the Lhari.

It was a big universe, with measureless millions of stars, and plenty of room for more than two intelligent civilizations. It wasn't surprising that the Lhari, who had only been traveling space for a couple of thousand years themselves, had never come across humans before. But they had been delighted to meet another intelligent race—and it was extremely profitable.

Because men were still held, mostly, to the planets of their own star-systems. Ships traveling between the stars by light-drive were rare and ruinously expensive. But the Lhari had the warp-drive, and almost overnight the whole picture changed. By warp-drive, hundreds of times faster than light at peak, the years-long trip between Vega and Earth, for instance, was reduced to about three months, at a price anyone could pay. Mankind could trade and travel all over their galaxy, but they did it on Lhari ships. The Lhari had an absolute, unbreakable monopoly on star travel.

"That's what hurts," Tommy said. "It wouldn't do us any good to have the star-drive. Humans can't stand faster-than-light travel, except in cold-sleep."

Bart nodded. The Lhari ships traveled at normal speeds, like the regular planetary ships, inside each star-system. Then, at the borders of the vast gulf of emptiness between stars, they went into warp-drive; but first, every human on board was given the cold-sleep treatment that placed them in suspended animation, allowing their bodies to endure the warp-drive.

He finished his drink. The increasing bustle in the crowds below them told him that time must be getting short. A tall, impressive-looking Lhari strode through the crowd, followed at a respectful distance by two Mentorians, tall, redheaded humans wearing metallic cloaks like those of the Lhari. Tommy nudged Bart, his face bitter.

"Look at those lousy Mentorians! How can they do it? Fawning upon the Lhari that way, yet they're as human as we are! Slaves of the Lhari!"

Bart felt the involuntary surge of anger, instantly controlled. "It's not that way at all. My mother was a Mentorian, remember. She made five cruises on a Lhari ship before she married my father."

Tommy sighed. "I guess I'm just jealous—to think the Mentorians can sign on the Lhari ship as crew, while you and I will never pilot a ship between the stars. What did she do?"

"She was a mathematician. Before the Lhari met up with men, they used a system of mathematics as clumsy as the old Roman numerals. You have to admire them, when you realize that they learned stellar navigation with their old system, though most ships use human math now. And of course, you know their eyes aren't like ours. Among other things, they're color-blind. They see everything in shades of black or white or gray.

"So they found out that humans aboard their ships were useful. You remember how humans, in the early days in space, used certain birds, who were more sensitive to impure air than they were. When the birds keeled over, they could tell it was time for humans to start looking over the air systems! The Lhari use Mentorians to identify colors for them. And, since Mentor was the first planet of humans that the Lhari had contact with, they've always been closer to them."

Tommy looked after the two Mentorians enviously. "The fact is, I'd ship out with the Lhari myself if I could. Wouldn't you?"

Bart's mouth twisted in a wry smile. "No," he said. "I could—I'm half Mentorian, I can even speak Lhari."

"Why don't you? I would."

"Oh, no, you wouldn't," Bart said softly. "Not even very many Mentorians will. You see, the Lhari don't trust humans too much. In the early days, men were always planting spies on Lhari ships, to try and steal the secret of warp-drive. They never managed it, but nowadays the Lhari give all the Mentorians what amounts to a brainwashing—deep hypnosis, before and after every voyage, so that they can neither look for anything that might threaten the Lhari monopoly of space, nor reveal it—even under a truth drug—if they find it out.

"You have to be pretty fanatical about space travel to go through that. Oh, my mother could tell us a lot of things about her cruises with the Lhari. The Lhari can't tell a diamond from a ruby, except by spectrographic analysis, for instance. And she—"

A high gong note sounded somewhere, touching off an explosion of warning bells and buzzers all over the enormous building. Bart looked up.

"The ship must be coming in to land."

"I'd better check into the passenger side," Tommy said. He stuck out his hand. "Well, Bart, I guess this is where we say good-bye."

They shook hands, their eyes meeting for a moment in honest grief. In some indefinable way, this parting marked the end of their boyhood.

"Good luck, Tom. I'm going to miss you."

They wrung each other's hands again, hard. Then Tommy picked up his luggage and started down a sloping ramp toward an enclosure marked TO PASSENGER ENTRANCE.

Warning bells rang again. The glare intensified until the glow in the sky was unendurable, but Bart looked anyhow, making out the strange shape of the Lhari ship from the stars.

It was huge and strange, glowing with colors Bart had never seen before. It settled down slowly, softly: enormous, silent, vibrating, glowing; then swiftly faded to white-hot, gleaming blue, dulling down through the visible spectrum to red. At last it was just gleaming glassy Lhari-metal color again. High up in the ship's side a yawning gap slid open, extruding stairsteps, and men and Lhari began to descend.

Bart ran down a ramp and surged out on the field with the crowd. His eyes, alert for his father's tall figure, noted with surprise that the ship's stairs were guarded by four cloaked Lhari, each with a Mentorian interpreter. They were stopping each person who got off the starship, asking for identity papers. Bart realized he was seeing another segment of the same drama he had overheard discussed, and wished he knew what it was all about.

The crowd was thinning now. Robotcabs were swerving in, hovering above the ground to pick up passengers, then veering away. The gap in the starship's side was closing, and still Bart had not seen the tall, slim, flame-haired figure of his father. The port on the other side of the ship, he knew, was for loading passengers. Bart moved carefully through the thinning crowd, almost to the foot of the stairs. One of the Lhari checking papers stopped and fixed him with an inscrutable gray stare, but finally turned away again.

Bart began really to worry. Captain Steele would never miss his ship! But he saw only one disembarking passenger who had not yet been surrounded by a group of welcoming relatives, or summoned a robotcab and gone. The man was wearing Vegan clothes, but