The Pharaoh's Secret (NUMA Files 13)

“Evaporation,” a man from Scotland said. “It’s bloody hot out here.”

Staring at the mud, Paul forgot all his aches and pains. He knew they were looking at a mystery. The appearance of a lake was one thing—hot and cool springs worked their way to the surface all the time—but for a lake to disappear almost overnight . . . that was something altogether different.

He scanned the surroundings to get an idea of the surface area and depth, making a rough estimate of the lake’s volume. “That much water couldn’t evaporate in two months,” he said. “Let alone two days.”

“Then where did it go?” the woman from the South asked.

“Maybe someone nicked it,” the Scotsman replied. “After all, this whole area is in the middle of a drought.”

The man was right about that. Tunisia was suffering badly, even by North African standards. But a thousand tanker trucks filled to capacity wouldn’t have drained a lake this size. Paul looked for a break in the landscape or some avenue of escape for the water to flow through. He saw nothing of the kind.

Flies began to buzz around them and the group went silent. Finally, the Southern woman had seen enough. She patted the tour

guide on the shoulder and turned back down the hill. “Afraid someone pulled the plug on you, honey. Sorry about that.”

In rapid succession the others followed, not interested in studying a mud hole. Even the guide left, talking the whole way down, desperately trying to explain what the lake had looked like just days before and insisting quite calmly that even though it was gone, there would be absolutely no refunds.

Paul lingered, considering what they saw and watching as a group of children began picking their way through the dried mud to get at the last remnants of water.

“She’s right,” he said to Gamay as she eased up beside him.

“About what?”

“About someone pulling the plug,” he said. “Springs like this bubble up from aquifers quite often. Usually when the layers of rock underneath crack and shift. Sometimes the water gets trapped, forms a lake like it apparently did here. Sometimes the spring keeps feeding it, sometimes it’s a one-shot deal. But even if the layers of rock shift again and cut off the water, the lake usually remains in place for months until the sun slowly bakes it dry. For this lake to vanish so suddenly, the water had to go somewhere else. But there’s no stream flowing away from here. The landscape is one big rocky bowl.”

“So if it can’t go up and it can’t go out, it must have gone down,” she said. “Is that your theory, Mr. Trout?”

He nodded. “Right back where it came from.”

“Have you ever heard of that happening before?”

“No,” Paul said. “As a matter of fact, I haven’t.”

As they marveled at the sight and took a few pictures, a man who’d been doing the same thing on a different section of the rim made his way over to them. He was rather short, perhaps five foot six, a floppy canvas hat covered his head and a layer of salt-and-pepper stubble covered his tanned face. A backpack, walking stick and binoculars suggested he was a hiker. But Paul noticed a yellow-and-black surveyor’s level in his hand.

“Hello,” the man said, tilting his hat up slightly. “I couldn’t help but overhear your discussion of the lake’s disappearance. All day long, people have been coming up that trail, shaking their heads with disappointment and walking away. You’re the first people I’ve overheard really trying to figure out what happened and where the water has gone. You’re not geologists by any chance?”

“I have a background in geology,” Paul said, offering his hand. “Paul Trout. This is my wife, Gamay.”

He shook Paul’s hand and then Gamay’s. “My name is Reza al-Agra.”

“How do you do,” she said.

“I’ve had better days,” he admitted.

Paul nodded toward the surveyor’s tools. “Did you come here to measure the lake?”

“Not exactly,” he replied. “Like you, I was trying to figure out how and why the water vanished. My first step was to determine how much water had been here in the first place.”

“We were happy just to guess,” Paul admitted, thinking a survey of the mud seemed like overkill.

“Yes, well . . .” Reza said, “I don’t have that luxury. I’m the director of water recovery for the Libyan government. I’m expected to be precise.”

“But this is Tunisia,” Gamay pointed out.

“I realize that,” he replied. “But I thought I should see it. In my profession, disappearing lakes are a bad omen.”

“It’s just one small lake in the middle of the desert,” Gamay said.