And another little tremor rattled the useless lamp on the side table.

Isaac felt the tremor but it didn't quite wake him. He had been sleeping a lot lately. He had lost some of his ability to distinguish between sleeping and waking.

The clock of the stars turned relentlessly inside him. In the darkness he dreamed things for which he had no words. There were many things for which he had no words. And there were words he knew but didn't understand and couldn't define: for instance, love.

I love you, Mrs. Rebka had whispered to him when no one but Isaac could hear.

He hadn't known what to say in return. But that was all right. She didn't seem to need an answer. I love you, Isaac, my only son, she had whispered, and then turned her face away.

What did that mean?

What did it mean when he closed his eyes and saw the cycling stars or the banked fires of an invisible thing deep in the western desert? What did it mean that he felt its liveliness and power?

What did it mean that he could hear a million voices, more voices than there were stars in the sky? What did it mean that out of that multitude he could call up the voice of Esh, a dead Martian boy? Was he remembering Esh or was something remembering Esh through him —remembering Esh's voice with the air in Isaac's lungs?

Because—and here was something Isaac did know—the act to which he had been summoned, to which all the tumbling fragments of Hypothetical machinery had been summoned from their lazy courses in the sky, was a remembering.

A remembering larger than the world itself.

He felt it coming. The crust of the planet trembled, its shivering rose up through the foundation of this old building, through the floor, the joists, the beams, through the bed frame and the mattress, until Isaac trembled along with it, the motion filling him with a heatless joy, memory and annihilation advancing with giant steps, with strides as long as continents, until at last he asked himself:

Is this love?

PART FIVE — IN THE COMPANY OF THE UNSPEAKABLE

CHAPTER TWENTY-FIVE

They had reached the outskirts of the oil concessions—the desolate, thin end of nowhere—when the third and most intense ashfall began.

There had been some warning, conveyed by Dr. Dvalis intermittently-functional telecom receiver. The precipitation had been relatively light in Port Magellan, but dense waves of it were falling in the west, as if focused there.

By the time Dr. Dvali announced this news, the threat was ominously visible. Lise, looking through the back window of the vehicle as it sped down the highway between two equally flat horizons, saw clouds the color of boiling slate materialize from a chalk-blue sky.

"We'll need to get under cover again," she heard Turk say.

To the southwest Turk could just make out the silver-black silhouettes of the Aramco drilling and pumping complex. Evacuated, presumably—a couple of the far towers seemed to be leaning off vertical, though that could be an illusion—but Turk guessed the site would still be guarded, both by machines and by armed men.

Fortunately they didn't need to head in that direction. The oil concessions had grown a ring of commerce around them, businesses run by lonely men for lonely men, strip clubs and bars and porn vendors, which meant that not far down the road they would find more respectable commercial concessions and housing for the hired workers. Which appeared as the two cars raced the black cloud flowing from the east: a gated side road, the gate unchained; a mall (grocery store, media retailers, a multi-mart); and a number of sturdy concrete buildings in which one- or two-room utility apartments were stacked like boxes.

Turk, in the lead car with Lise and Dr. Dvali, looked back and saw the second vehicle pulling into the mall lot. Dvali swung around and intercepted them in front of the grocer)? store.

"Supplies," Diane explained.

"We don't have time," Dvali said sternly. "We need to get under cover."

"Such as the building up ahead? I would suggest you break in or whatever you need to do, and we'll follow as soon as we find food."

Dvali clearly didn't like this idea, but just as clearly, Turk thought, it made sense: they had been running low on essentials and the ash storm might maroon them for a good long time. "Be quick about it," Dvali said unhappily.

Whoever designed this workers' barracks had made no attempt to disguise the institutional nature of the project. On the outside the building was weathered concrete and cracked pavement and an empty parking lot adjoining a tennis court enclosed in a chain-link fence, its net slumped in disarray. The door Turk approached was hollow steel painted industrial yellow, no doubt battered by the boots of hundreds of shit-drunk oil-riggers over the years, and it was locked, but the lock was fragile and gave way after some leverage with a tire-iron. Dvali fidgeted while Turk performed this task, glancing back at the approaching storm. The light was thinning already, the disc of the sun growing weak and obscure.

The door sprang loose and Turk stepped into the interior darkness, followed by Dr. Dvali and finally Lise.

"Uck!" Lise said. "God, it stinks!"

The evacuation must have been hurried. In many of the apartments that opened onto this hallway—more like cells, with their small high windows and cubicle bathrooms—food had been left to rot, toilets had been abandoned unflushed. They set about finding the most presentable first-floor residences and settled on three spaces, two adjoining and one cross-hall, from which the previous residents had removed the most obvious perishables. Lise reached up to swing open a window, but Dvali said, "No, not with the dust coming. We'll have to live with the stench."

There was no electricity, and the light was fading fast. Turk and Dvali unloaded their gear from the car, by which time the afternoon had turned into a smudgy twilight and the ash had begun to fall like snow. Dvali said, "Where are the others?"

"I could go hurry them up," Turk offered.

"No… they know where to find us."

Diane and Sulean Moi left Mrs. Rebka in the car with Isaac while they scrounged for groceries. The store had been nearly stripped, but in a stockroom in the back they discovered a few boxes of canned soups, not especially appetizing but possibly vital if the storm locked them indoors for any length of time. They ferried a few of these cartons out to the vehicle as the sky darkened. "One more box," Diane said at last, assessing the oncoming ash cloud, "and then we should get under cover."

A skylight above the aisles of the grocery store cast pale illumination on the empty shelves, some of which had been tumbled down by a previous tremor. Diane and Sulean each picked up a final carton and headed for the door, feet crunching on glass and litter.

As soon they reached the sidewalk they heard Isaac's screams. Diane dropped her carton instantly, spilling cans of creamed this-and-that down the sidewalk, and yanked open the passenger-side door and then craned her head back. "Help me!"

The boy's screaming was interrupted only by gasps for breath, and Diane couldn't help thinking that it must hurt simply to make such a noise, that a child's lungs shouldn't be capable of this awful sound. He thrashed and kicked and she grabbed his wrists and pinned them, which required more strength than she would have imagined. Mrs. Rebka was up front, fumbling the keycard into its slot. "He just started screaming—I can't calm him down!"

The important thing now was to get under shelter. "Start the car," Diane said.

"I tried! It won't!"