Map of Bones (Sigma Force 2)

Her uncle shook his head at the wonder. “All of this is a monument to Alexander and the lost Library of Alexandria.”

That reminded Rachel of something. “Weren’t there supposed to be books down here? Didn’t Septimus bury the most important scrolls of the library down here?”

Vigor searched around. “They must have been cleared out after the quake. When the clues were planted here. The knowledge must’ve been taken and sent to whatever hidden vault we seek. We must be close.”

Rachel heard the quaver in her uncle’s voice. What else might they discover?

“But before we move on,” Gray said, “we first must solve this riddle.”

“No,” Uncle Vigor said. “The riddle is not even exposed yet. Remember at St. Peter’s. We must pass some test. Prove our knowledge, like the Dragon Court did with their understanding of magnetism. Only after that was the secret revealed.”

“Then what are we supposed to do?” Gray asked.

Uncle Vigor stepped back, his eyes on the pyramid. “We have to activate this pyramid.”

“And how do we go about doing that?” Gray asked.

Vigor turned to Gray. “I need some soda.”

1:16 P.M.

GRAY WAITED for Kat to ferry up the last of the cans of Coke. They needed two more six-packs. “Does it matter if it’s diet Coke or regular?” Gray asked.

“No,” Vigor said. “I just need something acidic. Even citrus juice would work, or vinegar.”

Gray glanced to Rachel. She just shook her head and shrugged.

“Would you care to explain now?” Gray asked.

“Remember how magnetism opened the first tomb,” Vigor said. “We know that the ancients were well aware of magnetism. Lodestones were widely distributed and used. Chinese compasses date back to 200 B.C. To move forward, we had to prove our understanding of magnetism. It even led us here. A magnetic marker left underwater.”

Gray nodded.

“So another scientific wonder must be demonstrated here.”

Vigor was interrupted by the arrival of Kat. She rose up into the entry pool, bearing aloft two more six-packs, making it a total of four.

“We’re going to need Kat’s help for a few minutes,” Vigor said. “It’ll take four people.”

“How are things topside?” Gray asked Kat.

She shrugged. “Quiet. Monk fixed a radio glitch. That was the extent of any excitement.”

“Let him know you’ll be off the air for a couple minutes,” Gray said, uneasy, but they needed whatever was hidden here.

Kat dunked under, passing on the message. She then quickly climbed out and they all returned to Alexander’s tomb.

Vigor waved for them to disperse. He pointed to a copper urn at the pool’s edge. There were four of the pots. “Each of you take a six-pack of soda and take up a post by the jars.”

They spread out.

“Care to tell us what we’re doing?” Gray asked as he reached his copper jar.

Vigor nodded. “Demonstrating another scientific wonder. What we must show here is the knowledge of a force known even to the Greeks. They called it electrikus. A name for the static charge of a cloth rubbed over amber. They witnessed it in the form of lightning and along the masts of their sailing ships as Saint Elmo’s fire.”

“Electricity,” Gray said.

Vigor nodded. “In 1938, a German archaeologist named Wilhelm Koenig discovered a number of curious clay jars in the National Museum of Iraq. They were only fifteen centimeters tall. They were attributed to the Persians, the homeland of our biblical Magi. The odd thing about the tiny jars was that they were plugged with asphalt, and from the top protruded a copper cylinder with an iron rod inside. The conformation was familiar to anyone with knowledge of voltaic sciences.”

Gray frowned. “And for those not familiar?”

“The jars…they were the exact conformation of battery cells, even earning the name ‘the Baghdad Batteries.’”

Gray shook his head. “Ancient batteries?”

“Both General Electric and Science Digest magazine in 1957 replicated these jars. They primed them with vinegar, and the jars gave off significant volts of electricity.”

Gray stared down at the jars at his feet, remembering the monsignor’s request for soda, another acidic solution. He noted the iron rod sticking out of the top of the solid copper jar. “Are you saying these are batteries? Ancient Duracell Coppertops?”

He stared at the pool. If the monsignor was correct, Gray understood now why jars were resting in the seawater pool. Whatever shock was generated by the batteries would flow through the water to the pyramid.

“Why don’t we just jump-start the pyramid?” Kat said. “Bring down a marine battery from the boat?”

Vigor shook his head. “I think the activation is tied to the amount of current and the position of the batteries. When it comes to the magnitude of power in these superconductors—especially one this size—I think we should stick to the original design.”

Gray agreed. He remembered the quake and the destruction inside the basilica. That had been with only a single cylinder of m-state powder. He eyed the giant pyramid and knew they’d better heed the monsignor’s recommendation.

“So what do we do?” Gray asked.

Vigor popped the top to one of his sodas. “On my count, we fill up the empty batteries.” He stared around the group. “Oh, and I suggest we stand well back.”

1:20 P.M.

MONK SAT behind the boat’s wheel, tapping an empty can of soda on the starboard rail. He was tired of all this waiting. Maybe scuba diving wasn’t so bad. The water looked inviting as the day’s heat rose.

The loud rumble of an engine drew a glance across the harbor.

The hydrofoil, which had seemed to drop anchor, was on the move again. He listened to the engine throttle up. There seemed to be a bit of commotion on the deck.

He reached for his binoculars. Better safe than sorry.

As he raised the binoculars, he glanced to the monitor of the Aqua-Vu camera. The tunnel continued to be unmanned.

What was taking Kat so long?

1:21 P.M.

GRAY EMPTIED his third can into the cylinder core of his jar. Soon Coke was bubbling down the copper side of the battery. Full.

He stood up and took the last swig from his soda can.

Ugh…diet…

The others finished about the same time, standing and moving back.

A bit of carbonation frothed out the tops of all the cylinders. Nothing else happened. Maybe they had done it wrong, or the soda wouldn’t work—or even more likely, the monsignor’s idea was simply full of crap.