That theory had held until shortly after the Invasion, when tiny "quantum" black holes were discovered in the cometary zone, beyond the orbit of Pluto. These mysterious objects were tiny; the largest in use was only a fraction of a millimeter across. But their gravity was tremendous. If they came in close proximity to a material object, they would destroy it, and energy would be released. That energy could be captured and broadcast from the orbital power stations to receivers on the ground.

One of them had gotten away, two hundred years ago, as it was being warped into orbit around Pluto. It had drilled a ten-meter hole straight through the center of the planet. The area of destruction was much more extensive than that, with tidal disruptions and quakes as pressure forced rock to flow like warm butter and fill in behind the hole's passage.

"What keeps that from happening here?" she asked.

"It could happen," Vejay said. "But it's not a huge hole, and Poseidon's a small rock. It'd fall through slowly, and what with the irregularities we'd be able to catch it on the other side. See, look here, this is how it works."

Lilo studied the diagram as Vejay explained it to her. She had thought it an extravagance to use a black hole for the station's power supply, and her opinion was confirmed by the figures. The hole was capable of putting out enough power to run a small city; Poseidon was able to utilize only a fraction of the output, even after much of it was siphoned off to maintain the hole against the pull of gravity.

"It's just sitting out there right now," Vejay said. "It's got a nullfield under it, bowl-shaped, like this." He pointed out a hemisphere which hovered over the surface of Poseidon, open end pointed outward. "The field protects the equipment under it from overheating, or the rock from melting. Also it means you can go right up close under the thing to service the support facilities." He indicated three massive domes on the ground.

"The hole has a charge on it, and it's held up by these electromagnets. Big ones, supercooled."

"So how does this help us escape?"

Vejay cocked his head, studying the drawing as if seeing it for the first time. He looked up, baffled.

"Doesn't that nullfield hemisphere shape suggest anything to you? It's not the most efficient design—we could tune it to whatever shape we want when we take control—but it would work as it is now."

Lilo looked again. Of course, why hadn't she seen it?

"A rocket exhaust nozzle."

"You got it. The hole is just sitting down there in that bowl, which points up from the surface of Poseidon. When we dump matter in there—anything at all, but not too much of it—the hole's gravity compresses it. It compresses it so hard that any nuclear reaction you want to think of can take place. A lot of matter gets destroyed, and that means energy, which we can tap for our power needs here.

"Even at the rate we put matter into it right now, there's a slight thrust generated, since the bowl is open at the top. It's almost too small to measure when you realize the whole mass of Poseidon and the hole is resisting the acceleration. So what we'd do is drop rocks into the hole just like we're doing now. Only instead of using dust particles and measuring them out with an eye-dropper, we'd need a conveyor belt. We'd need a steady fuel supply.

"So we've solved the second problem. Now all we have to do is solve the first."

Lilo frowned. "Maybe I'm slow."

Niobe laughed. "Don't worry. I thought we were on our way when I saw this, too. Vejay, you go too fast. She just got here."

"Sorry," he said. "Okay. The second problem is where do we go when we eliminate all the Vaffas. Any of the Eight Worlds would execute the lot of us as illegal clones. With this, we can go anywhere. I suggest we go far away."

"You're talking about interstellar travel?"

"What else? This drive would get us up close to the speed of light. We probably couldn't push it much faster than a twentieth of a gee, but we'd get there. Alpha Centauri in maybe twenty years."

"But what about the mass... ah. I think I see."

"We'd have enough. We use the mass of Poseidon itself, of course, just like we do now."

Lilo thought about that for a while. It was awfully damn frustrating, because, while Vejay had not mentioned the first problem, she saw what it was. It would take construction, utilization of the heavy equipment that had been used to hollow out the corridors—a myriad of details. A space drive cannot be designed and slapped together overnight.

"How long do you think it would take to get it ready?"

He shrugged. "Working hard, with no unplanned complications, I might have it working in two weeks."

And Vaffa inspected the site every day. It always came back to Vaffa.

I began to sleep badly. Meeting Vejay and Niobe had fired up my hopes, whetted my appetite for actually doing something about getting away. I was still as far from escaping as ever, but I didn't feel like it. We had solved the easy end of the equation of freedom. The problems all still lay ahead. At least six of them, possibly as many as ten, all of them named Vaffa.

A Vaffa could be killed. It was difficult, but it had been done twice over the years by desperate people. I heard both stories told a hundred times. They could be ambushed and overpowered indoors. Outside, they were as invulnerable as their suits. Bury them alive under a ton of rock; their suit fields would protect them and they would last as long as their air held out—plenty of time to be rescued.

Bury them all at once? You could blow up the whole rock, but where would that leave you?

"What are they?"

"Sugar babies. Are you kidding? How could you not know what sugar babies are?"

But Lilo did not. They were in a large glass jar with a narrow neck that she had discovered in Cass's hideout. Apparently he had tired of them, but they seemed to have done well.

The bottom of the soil was covered with dark soil, and growing from it were five dwarf elm trees, three Douglas firs, and a lot of moss. There was a cave formed from piled rocks, and standing in the entrance to the cave were three bipedal figures, one millimeter tall. Their bodies were white, and the tops of their tiny heads were black. They looked just like little people.

"It looks like they have faces," she said, leaning closer.

"You aren't kidding. You've really never seen them before."

"Never." But as she said it, she had a funny feeling that it was not true. She shook her head, but the feeling persisted.

"Well, they do have faces. But take a closer look."

There was a magnifier embedded in the side of the jar. Lilo looked through it, and the illusion fell apart. What looked to be hair on the heads was just coloring of the exoskeleton, concealing multifaceted eyes. The faces were three dots and a line. The things were segmented at the joints and waist like marionettes, or like...

"Ants. These are ants."

"That's what they started off with," Cass confirmed. "They changed them. You can see the fifth and sixth legs at the waist. They're real small."

Lilo felt sick, but could not take her eyes from the creatures. More came from the cave, walking crazily on their hind legs, the jointed arms waving about.

"It's repulsive," she said. She wondered if she was going to throw up.

Cass grimaced. "Yeah. I know what you mean. I got them when I was younger and now I don't know what to do with them. I can't just kill them; it wouldn't feel right."

"Tweed lets you..."

"We can order stuff sometimes. The kits to build these were in the supplies from Luna a few years back. All the kids made them. I wish I'd asked for cat eggs instead."