Zoe looked away, her mind buzzing.

Jack is dead, and we're out here in the middle of Africa, alone and hunted...

Beside her, Lily stared into s.p.a.ce, blankeyed. Then she started sobbing-deep, aching, wrenching sobs. Alby put his arm around her.

"We can't give up," Wizard said softly but firmly. "Jack wouldn't want us to give up. We have to stay focused and find the Neetha and the Second Pillar."

Zoe was silent for a long time, her mind still racing. In one fell swoop, she'd learned the man she loved was dead and a great responsibility had fallen on her shoulders-the Neetha, the Pillars, keeping Lily and Alby safe-and she wasn't sure she could handle it.

She wanted to cry, too, but knew she couldn't in front of the others.

Then Lily spoke and Zoe blinked back to the present.

"I'm sorry," Lily said. "I didn't mean to let them know where we are-"

"Don't be sorry, honey," Zoe said kindly. "We all wanted to call him."

Lily looked at Zoe, tear streaks on her cheeks. Zoe returned her gaze, and then Lily dived into her arms and burst out crying again, clutching Zoe tightly.

As they embraced, Zoe looked out at the road ahead of them.

The junglecovered mountains of the Congo loomed over the western horizon. The Congo was far more rugged than Rwanda, more densely forested, more impenetrable.

Somewhere in there were the Neetha, a mysterious tribe known for their deformed faces and wanton savagery, the guardians of the Second Pillar.

And now, alone and without Jack, Zoe had to find them.

Around two that afternoon they arrived at the outskirts of Kamembe, where they quickly found the abandoned UN depot they were after.

It looked like a dump. The depot's tenfoothigh chainlink fence was broken in several places and near an old gate was a battered sign:UNITED NATIONS-DEPOT 409: AIRCRAFT REFIT AND REFUEL.

Through the fence, Zoe saw a few fuel trucks mounted on bricks, their tires and vital parts long gone, and a couple of rusty old Huey helicopters that no longer possessed any landing skids.

A man stepped out from behind the nearest chopper. A very tall black man.

Zoe whipped up her gun- "Zoe? Is that you?" he said.

Zoe heaved a sigh of relief and for the first time in days, smiled.

There, emerging from behind the rusty old chopper, was Solomon Kol.

Solomon had two porters with him, carrying fuel cans on poles across their shoulders.

"These are my friends," Solomon said. "They have fuel for your plane. We have been here since early morning and were starting to wonder if you had been waylaid by bandits."

"Almost," Wizard said.

"We also have food," Solomon smiled.

"Oh, Solomon," Zoe said, "we are so glad to see you."

They sat and ate inside the fenced UN depot.

"A friend of mine has a Fokker, for dusting crops. He flew us in this morning, dropping us off a few miles to the east of here," Solomon said. "There were rumors in the villages we pa.s.sed through of an announcement over the government radio network. It spoke of a vast reward to the person or persons who found a group of white fugitives believed to be in Rwanda. Our enemies have cast a wide net for you and they summon the common people to aid them-"

"Hey! I think I've got it..." Alby said suddenly.

He had been sitting apart from the others, still examining the charged First Pillar.

It had become something of an obsession for him, figuring out what the Pillar's glowing symbols meant. With Wizard's and Lily's help, he knew what some of them stood for, but now he'd made another connection.

"What is it, Alby?" Wizard said.

Alby held up the oblong gla.s.slike Pillar with its pyramidal void at one end. He showed its four long sides. All contained the glowing white writing.

"See this side, with the spiderweblike matrix on it. This matrix is actually a variety ofcarbon matrix-an extremely complex interconnection of carbon atoms, far more complex than anything we have today."

"Meaning?" Lily asked.

"Carbon forms the basis of diamonds, the strongest substance on Earth. Carbon fiber, too, is superstrong but light-fighter aircraft and race cars use it to reinforce their c.o.c.kpits.

Strong and light. t.i.tanium, steel, they're strong but they're heavy. This matrix, however, is something else: a carbonbased alloy that's unbelievably strong yet incredibly light."

"Technical knowledge..." Wizard breathed. "It's technical knowledge."

"Have you deciphered any of the other sides?" Zoe asked.

"Partially. This one here seems to be a representation of the star Sirius and its two companion stars. The second companion star is shown as a zeropoint field, the same stuff that our Dark Star is made of."

"Nice to know this may happen elsewhere in the universe," Wizard commented.

"The next side of the Pillar is even wilder," Alby said. "It, well, it seems to be an explanation of the Universe Expansion Problem."

"Goodness..." Wizard's eyes widened. "Are you sure?"

"Thewhat expansion problem?" Lily asked.

Wizard explained. "It's commonly accepted that our universe is expanding. The problem faced by astrophysicists and theoreticians, however, is that it should be expanding faster than it actually is. This has caused scientists to conclude that there is anegative energy or force somewhere out there holding the universe together-binding it, so to speak-and thus slowing its expansion. The discovery of the physical components of this negative energy would win you the n.o.bel Prize tomorrow."

Lily smiled at Alby. "Better start writing your speech."

"I don't think finding an ancient Pillar and reading it counts asdiscovering anything,"

Alby said.

"The point is," Wizard said, "these are incredible things to know incredibleknowledge.

Alby's discovery is essentiallythe explanation for the state of balance in our universe the sofarinexplicable balance that exists between a universe that has been expanding since the Big Bang yet which is held in perfect check by a counteracting force. This is momentous. Advanced knowledge being pa.s.sed down to us by an exceedingly generous prior civiliza-"

A scream pierced the air, echoing out over the hills. A completely random scream.

There was a momentary silence as they all looked out into the Rwandan countryside.

Alby's discovery had briefly made them forget where they were.

When all was silent again, Wizard said, "I'll be very interested to know what the last side of the Pillar says. Good work, Alby, you've donevery well. Jack always said you were a special one. Lily's lucky to have a friend like you."

Alby beamed.

Zoe had observed the entire exchange with interest-focusing on these problems and puzzles was a good way to keep their minds off the loss of Jack. She leaned forward, "So if this isknowledge, what is the next reward,heat ?"

All eyes turned to Wizard.

"Something similarly advanced, I a.s.sume. But somehow different from pure knowledge like this. I once knew an American academic who was interested in the Ramesean Stones, a fellow at MIT named Felix Bonaventura.

"Bonaventura was mostly interested in the second reward. He interpretedheat to mean energy, an energy source of some kind, since all our known sources of energy require the production of heat: coal, steam, internal combustion, even nuclear power. But if one could produce heat or motion without the need forfuel, one would have an unlimited supply of energy."

"Are you talking about perpetual motion?" Alby said in disbelief.

"That's exactly what Bonaventura thought the second reward was," Wizard said. "The secret of perpetual motion."

Zoe said, "It'd be something China would kill for. It's choking on its own coalbased pollution."

"Same for America," Alby said. "It wouldn't need Middle Eastern oil anymore."

"The whole world would change," Wizard said. "The Saudis and their vast oil reserves would no longer be needed. Coal would be useless. Why, warfare as we know it would be transformed. Did you know that by the end of World War II, the n.a.z.is were using horses and carts because they'd run out of petrol. As a reward, pureheat would certainly be a worldchanging one."

Throughout the afternoon, Solomon and Zoe set about repairing one of the Hueys in the UN compound. Unlike the trucks, the choppers' engines were more or less intact, and where one of them was missing parts, they could mostly scavenge matching parts from the other.

Late in the afternoon, Solomon came over from the chopper, wiping his hands on a rag.

"Ladies and gentlemen. Your helicopter is ready."

Wizard stood. "Then let's go find the Neetha."

DEMOCRATIC REPUBLIC OF THE CONGO.

DECEMBER 1113, 2007 THE RUSTY OLD UN Huey helicopter soared low over the junglecovered mountains of the eastern Congo, still without any landing skids.

Zoe flew, with Wizard beside her, flipping between a tangle of maps, notes, and his laptop computer.

"A few years ago I got Jack to do some research on the Neetha," he said, finding a certain page in his notes: NEETHA TRIBE.

Remote tribe from Democratic Republic of the Congo/Zaire region warlike much feared by other tribes cannibals Congenital deformities in all members, variety of Proteus Syndrome (bony growth on skull, similar to Elephant Man) Found by accident byHENRY MORTON STANLEY in 1876 Neetha warriors killed seventeen of his party Stanley barely escaped alive years later, he tried to find them again, but strangely he could not locate them.

Possibly the same tribe encountered by the Greek explorerHIERONYMUS during his expedition into central Africa in 205 B.C. (Hieronymus mentioned a tribe with terrible facial deformities in the jungles south of Nubia. It was from the Neetha that he stole the clear sphericalorb that was later used by the Oracle at Delphi.) BEST KNOWN EXPERT: DR. DIANE Ca.s.sIDY,Anthropologist from USC. But her whole 20man expedition went missing in 2002 while searching for the Neetha in the Congo.

Ca.s.sidy found this cave painting in northern Zambia and attributed it to ancestors of the Neetha: Seems to depict a hollowedout volcano with the Delphic Orb at the summit but its meaning is unknown.

"Hey, I've seen that painting!" Zoe said. "It was at..."

"It was at the First Vertex," Wizard said. "Which suggests a clear connection between our quest and the Neetha. The key, however, is Hieronymus." He clicked through the database on his laptop. "Hieronymus...Hieronymus...Ah, here it is!"

He'd found the entry he was after: a scan of an ancient scroll, written in Greek.

"What's that?" Lily asked.

"It's a scroll that was kept at the Library of Alexandria, a scroll written by the great Greek teacher and explorer, Hieronymus."

Years before, Wizard and Jack had uncovered a vast collection of scrolls in the Atlas Mountains-a collection which, it turned out, was that of the fabled Alexandria Library, long believed to have been destroyed when the Romans burned down the famous Library.

After months of careful scanning, Wizard had managed to load all the scrolls onto his various computers.

"Hieronymus was a truly exceptional man. Not only was he a great teacher, he was also an explorer beyond comparison, the Indiana Jones of the ancient world. He taught alongside Plato at the Academy, teaching no less a student than Aristotle himself. He was also the man who stole the Delphic Orb from the Neetha and took it back to Greece, where the Oracle at Delphi later used it to foretell the future."

"The Delphic Orb?" Zoe said as she flew. "You mean the Seeing Stone of Delphi? One of the Six Sacred Stones?"

"Yes," Wizard said. "Hieronymus stole it from the Neetha, but from what I've studied of him, he always intended to return it. That was why he wrote this scroll-it's a set of instructions detailing the location of the Neetha, so that the Orb could one day be returned."

"Was it ever returned?" Alby asked.

"After they saw its power, the Greeks didn't want to give it back," Wizard said, "but late in his life Hieronymus crept into the Oracle's templecave, grabbed the Seeing Stone, and fled from Greece by boat. He stopped in Alexandria-where he deposited these scrolls, written in Greek and Latin, at the Library-before he headed south into Africa. He was never seen again." Wizard turned to Lily. "Think you can translate this scroll?"

She shrugged. It was in Latin, and Latin was easy for her. "Sure. It says: "AT THE VALLEY OF THE ARBOREAL GUARDIANS AT THE JUNCTION OF THE THREE MOUNTAIN STREAMS.

TAKE THE SINISTER ONE.

THERE YOU WILL ENTER THE DARK REALM OF THE TRIBE THAT EVEN.

GREAT HADES FEARS.'"

"'The tribe that even great Hades fears'?" Zoe said. "Charming."

Solomon said, "The Neetha have a reputation so fearsome it has become myth many Africans use tales of Neetha bogeymen to frighten young children: cannibalism, human sacrifice, killing their young."

"Takes more than a scary story to frighten me off," Lily said in her best adult voice. "So what's the 'Valley of the Arboreal Guardians'? That seems to be the starting point."

"Arboreal means trees," Alby said. "The tree guardians?"

Wizard was clicking through more entries on his computer. "Yes, yes. I've seen a reference to just such a valley before. Here it is. Ahha...."

Lily leaned over, and saw on his screen the t.i.tle page of a book, an old 19th century pulp fictioner calledThrough the Dark Continent by Henry Morton Stanley.

"Stanley wrote many books about his expeditions in Africa, most of them pure romantic rubbish," Wizard explained. "This one, however, detailed his genuinely remarkable tripacross the African continent, from Zanzibar in the east to Boma in the west. Stanley departed from Zanzibar with a caravan of 356 people and, over a year later, emerged at the Congo River estuary near the Atlantic with only 115, all of them on the verge of starvation.

"Over the course of his journey, Stanley recounted numerous gun battles with native tribes, including one particularly gruesome skirmish with a tribe that resemble the Neetha.

Immediatelybefore that battle Stanley recounted traveling through an isolated jungle valley in which the trees had been carved into marvelous statues, towering statues of men, some of them over seventy feet high.