Zara said, “It sounds like an impossible plan.”
“That’s because it is,” Sam said. “But I don’t have another one — and we’re running out of time.”
He closed his eyes in the darkness and forced himself to rest. He would need to if he was to think clearly tomorrow.
In the complete darkness, Sam had no idea how long he’d slept. It was a deep sleep. He’d had a dream. It was vivid. One of those dreams in which you wake up and still wonder what was real and what was imagined.
He was crossing a desert in the night, navigating by the stars. Only he’d lost his way. Something terrible had happened to the celestial sky, and instead of an infinite myriad of stars and constellations, he saw nothing but the dark canvas of space. He was on a journey, searching for something important. He couldn’t quite remember what it was he was looking for, but he knew it was the most valuable and important quest he’d ever made. He was about to give up all hope of finding it — whatever it was.
He’d stopped walking, fearful of finding himself even more lost as the time went by. He wanted to cry. He felt so close and at the same time distant from whatever it was he was searching for. He tilted his head and looked straight up.
Above him a tiny dot erupted into a fireball in the pitch black canvas. The light glowed brighter until he was no longer able to look at it without hurting his eyes.
Sam opened his eyes. The massive dome structure was so bright he could see the entire place. Startled, he glanced at Tom and Zara. Both were still lying on the island next to him. It took a moment for Sam to realize the significance.
If everyone’s asleep, who turned on the lights?
Sam’s eyes followed the arch of the dome to its crest. At the very top of the dome, a massive oculus, maybe thirty feet in diameter, no longer displayed only darkness. Instead, it now erupted in sunlight, which reflected throughout the subterranean cavern.
Zara opened her eyes. “What the hell is that?”
Sam grinned. “I believe that’s the way out you said would be impossible to find.”
Chapter Sixty-Eight
The light traveled down through the oculus and onto the island. From there, it ricocheted around the dome, with increasing intensity, before sending a return light back through the original opening. Sam stared at the oculus. The light penetrating downwards appeared to be rectangular, but by the time it reflected off the water surrounding the island, the light appeared in the shape of a triangle. It surprised him, because the island clearly formed the shape of a perfect circle, positioned precisely below the oculus. The light lasted no more than fifteen minutes and then disappeared, leaving them in total darkness.
Sam increased the temperature on his DARPA thermal suit, and the darkness slowly turned to a stable blue glow. He looked at Zara and smiled, “See, I told you we’d find a way out.”
She returned his smile. “What way out? You haven’t got us out of here yet!”
“The light. That was sunlight. Where it can get in, we can get out.”
She laughed. “That’s the stupidest thing I’ve heard you say. The light could have just as easily come through an ancient pipe, no larger than a coin in diameter. The light will get in but nothing will get out.”
“That’s a possibility,” Sam conceded. “But I have another idea.”
Tom looked at him. The edge of his lip curving upwards, not quite in a grin, but definitely as a statement — this ought to be good! “Go on, Sam. Let’s hear it.”
Sam opened his mouth to speak. Paused and then grinned as though he’d suddenly been delivered a revelation. “It’s the light. You see, the light that reflected upwards did so in the shape of a triangle.”
Silence.
Zara asked, “What exactly is it about the triangular light that intrigues you, Sam?”
“The light that descended through the oculus was in the shape of a rectangle, but when it reflected off the waters surrounding the island, it did so in the shape of a triangle.”
Tom asked, “But the island is a perfect circle?”
“Well spotted, Mr. Bower!” Sam said. “I have a theory the island is not an island at all. Instead, I believe it floats. Or that is to say, it once did, when the water levels were much higher than they are today.”
“The island floats?” Zara asked.
“Used to,” Sam corrected her. “Probably still does if the water level ever rises high enough again.”
Tom smiled. “You think this was a giant water holding tank. Like the heart of the Garamante’s last major water stores. It was protected and monitored. The light shines through the opening, down to the island. If the water is low, it shows a triangle, if it is high it shows a rectangle, if it’s full, it shows a circle.”
“Exactly,” Sam said. “Maybe this was the lowest point in the Garamante Empire. As water flows downward, all irrigation tunnels fed through to this chamber here. The masters of the day must have known they were using enormous amounts of fossil water to irrigate their arid lands. They must have been terrified it would one day disappear. So they built this chamber and every so often, would shine light through a tunnel to get a reading of the water’s depth.”
Zara asked, “Why not simply walk down and measure it?”
Sam shook his head. “Not that simple. This place could be hundreds of miles from the main city. It would take days or weeks to send someone to test the water levels. Instead, they were grand engineers and built a system of reflective stones to shine sunlight into their holding tank.”
No one made a comment.
Sam smiled. “So what do you think?”
Zara smiled. “I think you have a fantastic imagination, but even if you were right, it doesn’t help us get out of here.”
“Why not?” Sam asked.
“Because that oculus must be eighty feet above us, and there’s no way to reach it.”
Sam glanced at the base of the dome, where the triangular-shaped pendentives met the water. “I had an idea about that too.”
“What?” she asked.
Sam smiled. “Have you ever been to Florence?”
Chapter Sixty-Nine
Sam spoke slowly. His eyes stared vacantly at the massive dome, but his mind wandered as though he was reliving a time nearly twenty years earlier when his father had taken him to visit the Italian city of Florence.
Sam said, “It’s been many years since I last visited the great city, but one view still remains from my trip. One vision, so fantastic that I found its impression permanently embedded somewhere in the part of my brain that permanently stores valuable information.” He grinned. “Among the contour of spires and domes one regal structure dominates the city’s skyline.”
Zara smiled. “Florence Cathedral.”
Sam nodded. “The construction of Il Duomo di Firenze, as it is known to the locals, started in 1296 in the Gothic style with the design by Arnolfo di Cambio. But it wasn’t completed until 1436 because until that time, no one could decide how to build such an enormous masonry dome without its weight causing the structure to collapse during the building process. Do you know who worked it out?”
She nodded. Her eyes were wide. “Filippo Brunelleschi, a Master Goldsmith.”
Tom sat down. Disappointment showing across his face that he was being forced to hear another history lesson before being able to escape.
Sam continued. “The building of such a masonry dome would have posed many technical problems. Brunelleschi looked to the great dome of the Pantheon in Rome for solutions. The dome of the Pantheon was formed by a single shell of concrete, the formula for which had long since been forgotten. Soil filled with silver coins had held the Pantheon dome aloft while its concrete set. This could not be the solution in the case of a dome this size, and massive shoring would put the church out of use. For the height and breadth of the dome, starting 171 feet above the floor and spanning 144 feet, there was not enough timber in Tuscany to build the scaffolding and forms. Either of you like to hazard a guess how Brunelleschi overcame this problem?”