Perry looked down. He could see a dozen scattered lakes and ponds, steaming and shrinking, giving up their stored moisture to the atmosphere. Quake needed the protection of that layer of water vapor to shield it from the direct rays of Mandel and Amaranth.

What could not be shielded were the growing tidal forces. The ground around the shrinking lakes was beginning to fracture and heave. Conditions were steadily worsening as the car flew closer to the place where J’merlia and Kallik had been found.

Perry wrestled the car’s controls and wondered. A landing in these conditions would be difficult. How long would it take to drop J’merlia and Kallik at their car and move back to the relative safety of the air? And if there was no sign of Atvar H’sial and Louis Nenda, could they leave the two slaves alone on the surface?

They had not much farther to go. In ten more minutes he would have to make the decision.

And in thirty hours, Summertide would be here. He risked a slight increase in airspeed.

A glow of ruddy light began to appear in the sky ahead. Perry peered at it with tired eyes.

Was it Amaranth, seen through a break in the clouds? Except that no cloud break was visible. And the bright area was too low in the sky.

He stared again, reducing speed to a crawl until he was sure. When he was finally certain, he turned in his seat.

“Councilor Graves, and J’merlia. Would you come forward, please, and give me your opinion on this?”

It was a formality. Perry did not need another opinion. In the past few hours there had been intense vulcanism in the area ahead. Right where J’merlia and Kallik had been picked up, the surface glowed orange-red from horizon to horizon. Smoking rivers of lava were creeping through a blackened and lifeless terrain, and nowhere, from horizon to horizon, was there a place for an aircar to land.

Perry felt a shiver of primitive awe at the sight — and a great sense of relief.

He did not have to make a decision after all. Quake had made it for him. They could head at once for the safety of the Umbilical.

The arithmetic was already running in his head. Seven hours’ flight time from their current location. Add in a margin for error, in case they had to fly around bad storms or reduce airspeed, and say it might take as much as ten. And it would be eighteen hours before the Umbilical withdrew from the surface of Quake.

That was an eight-hour cushion. They would make it with time to spare.

Noise meant inefficiency. So did mechanical vibration. The motors of an aircar in good shape were almost silent, and its ride was silky smooth.

Darya Lang listened to the wheezing death rattle behind her and felt the floor tremble beneath her feet. There was no doubt about it, the shaking was getting worse. Getting worse fast, noticed easily above the buffeting of the wind.

“How much farther?” She had to shout the question.

Hans Rebka did not look up from the controls, but he shook his head. “Fourteen kilometers. May be too far. Touch and go.”

They were churning along no more than a thousand meters above the surface, just high enough to escape added dust in the intake vents. The ground below was barely visible, ghostly and indistinct beneath a fine haze of swirling powder.

Lang looked higher. There was a thin vertical strand far off in front of them. She cried out, “I can see it, Hans! There’s the foot of the Stalk!” At the same moment Rebka was shouting, “No good. We’re losing lift.”

The aircar engine began to sputter and gasp. Spells of smooth flight at close to full power were followed by grinding vibration and seconds of sickening descent. They dropped into the dust layer. The silver thread of the Umbilical vanished from Darya’s view.

“Six kilometers. Four hundred meters.” Rebka had taken a last sighting before they entered the storm and was flying on instruments. “I can’t see to pick the landing site. Check your harness and make sure your mask and respirator are tight. We may be heading for a rough one.”

The aircars were sturdy craft. They had been designed to fly in extreme conditions; but one thing they could not guarantee was a soft landing with an engine worn to scrap by corundum dust. The final gasp of power came when the instruments showed an altitude of twenty meters. Rebka changed flap setting to avoid a stall and brought them in at twice the usual landing speed. At the last moment he shouted to Darya to hold tight. They smacked down hard, bounced clear over a rock outcrop big enough to remove the car’s belly, and slithered to a stop.

“That’s it!” Rebka had hit the release for his own harness and was reaching over to help Darya while they were still moving. He took a last look at the microwave sensor and turned to give her a grin of triumph. “Come on, I’ve got the bearing. The foot of the Umbilical’s less than half a kilometer ahead.”

Ground conditions were much better than Darya had expected. Visibility was admittedly down to a few tens of meters, and wind sounds were punctuated by the boom of distant explosions. But the ground was calm, flat, and navigable, except where a row of house-sized boulders jutted up like broken teeth. She followed Rebka between two of them, thinking how lucky they were that the engine had failed when it did, and not a few seconds later. They would have flown on and smashed straight into those rocks.

She was still not convinced that Quake was as dangerous as Perry claimed, and she had a lingering desire to stay and explore. But having flown so far to reach the Umbilical, it made sense to use it. She peered ahead. Surely they had walked at least half a kilometer.

Not looking where she was going, she slipped on a thick layer of powder, slick and treacherous as oil. Rebka in front of her fell down in a cloud of dust, rolled over, and staggered to his feet. Instead of shuffling onward he halted and pointed straight up.

They had emerged into a region shielded from the wind. Visibility had improved by a factor of ten. A circular disk, blurred in outline by high-level windblown dust, hung above them in the sky. As they watched, it lifted higher and shrank a fraction in apparent size.

His cry coincided with her understanding of what she was seeing.

“The foot of the Stalk. It’s going up.”

“But we got here earlier than we expected.”

“I know. It shouldn’t be doing that. It’s rising way ahead of time!”

The Umbilical was fading as they watched, its club-shaped bottom end receding into the clouds and blown dust. Around its rising base stood the apron supporting the aircars. She knew their size and tried to judge the height. Already the lower end must have risen almost a kilometer above the surface.

She turned to Rebka. “Hans, our car! If we can get back there and take it up—”

“Won’t work.” He moved to put his head close to hers. “Even if we could get the car into the air, there’s nowhere to land on the base of the Umbilical. I’m sorry, Darya. This mess is my fault. I brought us, and now we’re stuck here. We’ve had it.”

He was speaking louder than necessary — as if to make nonsense of his words the wind had dropped completely. The dust in the air began to thin, the surface was quiet, and Darya could see right back to their aircar. Above them the foot of the Umbilical was visible, hovering tantalizingly close.

It was the worst possible time for such a thought, but Darya decided that a little anguish in Hans Rebka’s voice made him nicer than ever. Self-confidence and competence were virtues — but so was mutual dependence.

She pointed. “It’s not going any higher, Hans. Who’s controlling it?”

“Maybe nobody.” He was no longer shouting. “The control sequences can be preset. But it could be Perry and Graves — they may have taken it up just to get clear of the surface. Maybe they’re holding it there, waiting to see if we show up. But we can’t reach them!”