Tolland looked only partially comforted, his relief apparently clouded by a deeper mystery. "I can't be for sure without a microscope," Tolland said, "but it looks to me like this is a bioluminescent plankton from the phylum Pyrrophyta. Its name means fire plant. The Arctic Ocean is filled with it."

Corky shrugged. "So why'd you ask if they were from space?"

"Because," Tolland said, "the meteorite was buried in glacial ice-fresh water from snowfalls. The water in that hole is glacial melt and has been frozen for three centuries. How could ocean creatures get in there?"

Tolland's point brought a long silence.

Rachel stood at the edge of the pool and tried to get her mind around what she was looking at. Bioluminescent plankton in the extraction shaft. What does it mean?

"There's got to be a crack somewhere down there," Tolland said. "It's the only explanation. The plankton must have entered the shaft through a fissure in the ice that allowed ocean water to seep in."

Rachel didn't understand. "Seep in? From where?" She recalled her long IceRover ride in from the ocean. "The coast is a good two miles from here."

Both Corky and Tolland gave Rachel an odd look. "Actually," Corky said, "the ocean is directly underneath us. This slab of ice is floating."

Rachel stared at the two men, feeling utterly perplexed. "Floating? But... we're on a glacier."

"Yes, we're on a glacier," Tolland said, "but we're not over land. Glaciers sometimes flow off a landmass and fan out over water. Because ice is lighter than water, the glacier simply continues to flow, floating out over the ocean like an enormous ice raft. That's the definition of an ice shelf... the floating section of a glacier." He paused. "We're actually almost a mile out to sea at the moment."

Shocked, Rachel instantly became wary. As she adjusted her mental picture of her surroundings, the thought of standing over the Arctic Ocean brought with it a sense of fear.

Tolland seemed to sense her uneasiness. He stamped his foot reassuringly on the ice. "Don't worry. This ice is three hundred feet thick, with two hundred of those feet floating below the water like an ice cube in a glass. Makes the shelf very stable. You could build a skyscraper on this thing."

Rachel gave a wan nod, not entirely convinced. The misgivings aside, she now understood Tolland's theory about the origins of the plankton. He thinks there's a crack that goes all the way down to the ocean, allowing plankton to come up through it into the hole. It was feasible, Rachel decided, and yet it involved a paradox that bothered her. Norah Mangor had been very clear about the integrity of the glacier, having drilled dozens of test cores to confirm its solidity.

Rachel looked at Tolland. "I thought the glacier's perfection was the cornerstone of all the strata-dating records. Didn't Dr. Mangor say the glacier had no cracks or fissures?"

Corky frowned. "Looks like the ice queen muffed it."

Don't say that too loudly, Rachel thought, or you'll get an ice pick in the back.

Tolland stroked his chin as he watched the phosphorescing creatures. "There's literally no other explanation. There must be a crack. The weight of the ice shelf on top of the ocean must be pushing plankton-rich sea-water up into the hole."

One hell of a crack, Rachel thought. If the ice here was three hundred feet thick and the hole was two hundred feet deep, then this hypothetical crack had to pass through a hundred feet of solid ice. Norah Mangor's test cores showed no cracks.

"Do me a favor," Tolland said to Corky. "Go find Norah. Let's hope to God she knows something about this glacier that she's not telling us. And find Ming, too, maybe he can tell us what these little glow-beasties are."

Corky headed off.

"Better hurry," Tolland called after him, glancing back into the hole. "I could swear this bioluminescence is fading."

Rachel looked at the hole. Sure enough, the green was not so brilliant now.

Tolland removed his parka and lay down on the ice next to the hole.

Rachel watched, confused. "Mike?"

"I want to find out if there's any saltwater flowing in."

"By lying on the ice without a coat?"

"Yup." Tolland crawled on his belly to the edge of the hole. Holding one sleeve of the coat over the edge, he let the other sleeve dangle down the shaft until the cuff skimmed the water. "This is a highly accurate salinity test used by world-class oceanographers. It's called 'licking a wet jacket.'"

Out on the ice shelf, Delta-One struggled with the controls, trying to keep the damaged microbot in flight over the group now assembled around the excavation pit. From the sounds of the conversation beneath, he knew things were unraveling fast.

"Call the controller," he said. "We've got a serious problem."

40

Gabrielle Ashe had taken the White House public tour many times in her youth, secretly dreaming of someday working inside the presidential mansion and becoming part of the elite team that charted the country's future. At the moment, however, she would have preferred to be anywhere else in the world.

As the Secret Serviceman from the East Gate led Gabrielle into an ornate foyer, she wondered what in the world her anonymous informant was trying to prove. Inviting Gabrielle into the White House was insane. What if I'm seen? Gabrielle had become quite visible lately in the media as Senator Sexton's right-hand aide. Certainly someone would recognize her.

"Ms. Ashe?"

Gabrielle looked up. A kind-faced sentry in the foyer gave her a welcoming smile. "Look over there, please." He pointed.

Gabrielle looked where he was pointing and was blinded by a flashbulb.

"Thank you, ma'am." The sentry led her to a desk and handed her a pen. "Please sign the entry log." He pushed a heavy leather binder in front of her.

Gabrielle looked at the log. The page before her was blank. She recalled hearing once that all White House visitors sign on their own blank page to preserve the privacy of their visit. She signed her name.

So much for a secret meeting.

Gabrielle walked through a metal detector, and was then given a cursory pat down.

The sentry smiled. "Enjoy your visit, Ms. Ashe."

Gabrielle followed the Secret Serviceman fifty feet down a tiled hallway to a second security desk. Here, another sentry was assembling a guest pass that was just rolling out of a lamination machine. He punched a hole in it, affixed a neck cord, and slipped it over Gabrielle's head. The plastic was still warm. The photo on the ID was the snapshot they had taken fifteen seconds earlier down the hall.

Gabrielle was impressed. Who says government is inefficient?

They continued, the Secret Serviceman leading her deeper into the White House complex. Gabrielle was feeling more uneasy with every step. Whoever had extended the mysterious invitation certainly was not concerned about keeping the meeting private. Gabrielle had been issued an official pass, signed the guest log, and was now being marched in plain view through the first floor of the White House where public tours were gathered.

"And this is the China Room," a tour guide was saying to a group of tourists, "home of Nancy Reagan's $952 per setting red-rimmed china that sparked a debate over conspicuous consumption back in 1981."

The Secret Serviceman led Gabrielle past the tour toward a huge marble staircase, where another tour was ascending. "You are about to enter the thirty-two-hundred-square-foot East Room," the guide was narrating, "where Abigail Adams once hung John Adams's laundry. Then we will pass to the Red Room, where Dolley Madison liquored up visiting heads of state before James Madison negotiated with them."