Down in the hall,there was no fourth wall opposite the stairmountain.

Indeed directly opposite the huge staircase, past the forest of ornate columns, was nothing at all: the polished floor of the hall simply ended abruptly at a sharp edge, a railless balcony five hundred feet wide, essentially a great viewing platform that looked out over an even larger s.p.a.ce of more darkness.

But from their vantage point at the top of the staircase, Jack and the others couldn't see what lay inside this larger s.p.a.ce, so they descended the stairs, looking like ants against the gargantuan hall.

They were halfway down the stairs when Jack saw what lay in the larger s.p.a.ce.

He stopped dead.

"We're gonna need more flares," he breathed.

THE VERTEX AT ABU SIMBEL.

THE FIRST VERTEX OF THE MACHINE.

JACK, WIZARD, AND ZOE crossed the vast floor of the Hall, pa.s.sing through the forest of superhigh columns, before they came to the edge of the hall, the point where it looked out over a larger underground void.

A gargantuan abyss dropped away before them. Deep and black and at least a thousand feet wide, it plummeted to unfathomable depths, into the densest darkness Jack had ever seen.

And mounted over it, suspended from the flat stone ceiling above the abyss, was a colossal pyramid-hanging inverted, upside down-perfectly cut and, by the look of it, of exactly the same dimensions as the Great Pyramid at Giza. It looked beyond ancient, beyond anything mankind could hope to build. Its flanks blazed with a l.u.s.trous bronze sheen.

Jack was reminded of the Pyramid Inverse at the Louvre in Paris-the beautiful upside down gla.s.s pyramid that hung over a smaller one. Made famous in the blockbuster novel The Da Vinci Code, its construction was shrouded in both Masonic and neopagan myth.

He also thought of the Hanging Gardens of Babylon, built as they were into a giant natural stalact.i.te in a great cavern in southern Iraq, and it struck him that perhaps the Gardens were built in homage to this.

Either way, the incredible size of the pyramid dwarfed the hall in which Jack, Wizard, and Zoe stood, the hall that until now had seemed so gigantic.

"Jack. Zoe. Meet the Machine," Wizard said.

Jack checked his watch.

It was 6:02A.M. The Jovian equinox would be at 6:12.

They'd made good time.

His radio squawked.

"Huntsman, you still alive down there?"Pooh Bear asked anxiously.

"We're in. We've found the Machine."

"Sky Monster just called. He's picked up a large force of land vehicles heading this way from Aswan. Over a hundred vehicles coming in behind the tourist coaches."

"ETA?" Jack asked.

"An hour, maybe less."

Jack did some calculations in his head. "We can be gone by then. Just."

As Jack spoke into the radio, Zoe and Wizard examined the walls of the hall.

They were literally covered in images-thousands and thousands of beautiful and intricate carvings.

Some they recognized, like the Mystery of the Circles, the circular symbol for the Machine, and even the layout of Stonehenge was there. But others were completely new: Zoe quickly pulled out a highres Canon digital camera and started clicking away, trying to capture as many of the images as she could.

"That's Ur," Wizard exclaimed, pointing at the second to last image.

"It is?" Zoe said.

"It's the layout of the ancient city of Ur, in Mesopotamia. Ur famously had two walled harbors, one to the west, the other to the north-you can see both of them clearly in the carving. Until the Great Pyramid was built, the Ziggurat at Ur was the tallest building in the world. And do you know what the word 'Ur' means?"

"Tell me."

"Light. The City of Light."

Taking pride of place in the center of the wall was a huge polished obsidian plaque. Every carving in it was edged with gold and its ornate frame also appeared to be cut from a single square piece of gold: "Oh my G.o.d, the six vertices..." Wizard breathed. "That symbol repeated on the left, an inverted triangle surmounting a rectangle, is Thoth for 'vertex.' This carving is a description ofall six vertices. I'll have to get Lily to decipher it."

Zoe snapped several photos of the plaque, then stared at the incredible hall around them and the gravitydefying pyramid suspended above the abyss.

"Wizard, who could build a place like this?" she asked. "Not ancient man. Not even modern man could do something like this."

"This is true," Wizard said. "So who could? Extraterrestrial visitors? Some think so- over 70 percent of people believe that the Earth has been visited by aliens at some point in history. And if they exist, perhaps aliens did visit our planet and build these structures.

But I don't subscribe to that view."

"What do you think?"

"He thinks men built them," Jack said, joining them, scanning the walls as he did so.

"Hey, it's Ur."

"Men?" Zoe frowned. "But I thought you agreed that neither modern nor ancient man could have-"

"I did agree. But I didn't rule out a race ofsuper ancient men," Wizard said.

"The past civilization theory," Jack said.

"Yes," Wizard said. "The theory that ours is not the first advanced civilization to flourish on this planet. That over the eons, in between asteroid impacts, comet strikes, and deadly Dark Stars, humantype beings have on numerous occasions risen above their animal neighbors, thrived, and then died out, only to rise again millions of years later."

"You think a previous civilization ofpeople built all this?" Zoe asked.

"Yes. A highly advanced human civilization, far more advanced than we are today. Why, did you notice how all the doors and steps we have pa.s.sed through to get here haveall been suited to our size and stature? This is not coincidence. That a.n.a.lien culture would buildhuman sized steps would be an astronomical coincidence. No, this structure-this wonderful structure-was built by human hands a long,long time ago."

"Humans who despite their advancements couldn't save themselves from extinction," Zoe pointed out.

"Maybe something else killed them," Jack said. "While they were building this, a rogue asteroid might have wiped them out."

Wizard nodded. "A lot can happen in a hundred million years. Entire species can emerge, evolve, thrive, and become extinct in that time. By contrast, modernh.o.m.o sapiens is only a hundred thousand years old. And hey, at least the people who built this Machine were trying to save themselves from the future return of the Dark Star."

"Wizard, sorry to interrupt, but would you mind taking a look at this." Jack had moved to the edge of the balcony and was gazing at the colossal inverted pyramid through a pair of binoculars.

The peak of the upsidedown pyramid hovered level with their balcony, but it was still three hundred feet-about ninety yards-away.

"The peak isn't pointed," he said, handing the binoculars to Wizard. "It's flat at the summit."

"Like the Great Pyramid was?" Zoe said.

"Sort of, but smaller. Much smaller," Wizard said. "About the size of"-he looked at the Pillar in Jack's hands "-that."

"So how do we get over there to place it?" Zoe asked.

"I'm guessing the same way we got in here," Jack said, pointing to the floor at his feet.

Zoe looked down-and saw the symbol for the Machine engraved into the marble floor beneath Jack's boots. Again, the rectangles in it were lifesized.

Jack placed the cleansed Pillar into the rectangular slot nearest to the abyss.

No sooner had it slotted into place than a deep rumbling could be heard.

Jack snapped left, then right, but couldn't see any obvious source of the sound. Wizard and Zoe did the same.

And then Jack saw it.

Saw a great narrow bridge emerging from the wall of the abyssdirectly below him. It folded upward as it emerged from the wall, like a drawbridge that foldsup into place not down, a long railless stone bridge.

Accompanied by the great rumbling, it rose up and up until with a loudboom it stopped perfectly in front of West, a great leaping tongue of stone that formed a half bridge stretching out over the abyss from his feet all the way to...the inverted summit of the pyramid.

"Nice..." Jack said.

Gripping his cleansed Pillar, Jack West Jr. stepped out onto the bridge, absolutely tiny against the vastness of the hall, the abyss and the colossal pyramid.

The sheer rockwalled abyss below him seemed almost bottomless, disappearing into infinite black.

Jack tried not to think about it and kept his eyes fixed forward as he approached the gigantic bronze pyramid.

Wizard and Zoe watched him every step of the way.

Then Jack came to the end of the bridge, to the summit of the upsidedown pyramid...

...just as the clock struck 6:11A.M.

UP ON THE SURFACE of the lake, the first rays of dawn were creeping over the horizon.

Alby had set up his telescope on the surface of the pyramidshaped island, just above the two bobbing Zodiacs.

He was bent over the eyepiece when he called, "Saturn has just risen over Jupiter! The gap is coming...now!"

Jack's watch ticked over to 6:12.

After all the grandeur of the hall and its staircase and the great pyramid and the vast abyss, Jack found it odd that the peak of the ma.s.sive structure could be so small when seen up close- Suddenly the pyramid began to hum.

It was a lowthrumm -a deep and powerful vibration that resonated throughout the entire cavern.

Jack's eyes went wide.

"Captain West,"came Alby's voice on the radio."The t.i.tanic Rising has just begun. You now have approximately one minute to lay the Pillar."

"Thanks," Jack replied. "Somehow I had the feeling it'd begun."

Standing at the very end of the elongated bridge, high above an abyss of indeterminate depth, he examined the summit of the thrumming bronze pyramid.

As he'd noted from the balcony, the ma.s.sive pyramid did not end at a sharp triangular point. Rather, it was flat. The great structure ended in a very small squareshaped flat section barely a handspan wide, as if its tiny capstone had once upon a time been sliced off.

Set into this square summit was an equally square hole-one that, Jack saw immediately, matched the size of his Pillar.

"Wizard?" he said into his radio. "Any final thoughts? There's no ceremonial thing I have to do?"

"Not that I know of,"Wizard replied."Just insert the Pillar into the pyramid."

"OK then..."

Jack took a final glance at his watch. It was still 6:12A.M.

Then, gripping his Pillar with both hands, standing high above a bottomless abyss far beneath the surface of the world, he inserted the cleansed Pillar into the matching hole in the pyramid.

THE PILLAR slotted into the pyramid...

...and instantly lodged inside it, halfin, halfout of the pyramid, firmly locked in place.

The ominous thrumming ceased instantly.

Silence hung in the air.

Jack held his breath.

Then-bam!-the clear diamond Pillar, now lodged in the peak of the pyramid,blazed to life, glowing with intense white light.

Jack reeled away, shielding his eyes.

The blinding white light illuminated the entire cavernous s.p.a.ce around him, showing Jack for the first time just how deep the abyss below him was. It was unimaginably huge, its sheer walls plunging down beyond even the reach of the blazing light of the Pillar.

But then, with a great thunderclap, a thick column of laserlike white light blasted downward from the Pillar and shot down the shaftlike abyss, rocketing toward the core of the Earth.

Jack couldn't watch it properly-it was just too bright.

Then with startling suddenness, the laser retreated back up into the Pillar and the pyramid, and just as quickly as it had sprung to life, the event was over, and the cavern was dark again-save for the pathetic light of Jack's amber flares.

Uncovering his eyes, Jack peered up at the ma.s.sive pyramid, staring in awe at the ancient mechanism.