“I wonder if we’ve been ‘shafted,’ literally,” Zavala said.

“Don’t give up yet,” Gamay said. “The old kitchen worker was pretty specific. Let’s try that room.”

She swam through an opening into a space around a quarter the size of the kitchen. Shelves lined the walls, indicating the room had been a pantry. She dropped down until her face mask was inches above the floor, and, after searching for a short time, she found a rectangular raised section. She brushed away the silt and found hinges and a rusty padlock.

Zavala reached into a waterproof bag attached to the D ring of his harness and pulled out an angled pry bar around a foot long. He inserted the bar under the trapdoor cover only to have the rotten wood break into pieces. He pointed his light down the shaft. The blackness seemed to go on forever.

“I don’t hear you saying ‘Me first,”’ Gamay said.

“You are slimmer than I am,” Zavala said.

“Lucky me.”

Gamay’s reluctance was feigned. She was an intrepid diver and would have gladly arm-wrestled Zavala for the chance to find the mine. At the same time, she had done enough diving to realize she had to be extracautious. Cave diving requires an uncanny calmness. Every move must be deliberate and well thought out in advance.

Zavala tied a length of thin nylon line to the leg of a cabinet and the other end to his pry bar. He lowered the bar into the shaft, but it didn’t touch bottom, even after fifty feet were played out.

Gamay examined the wood-covered sides of the shaft. The wood was soft, but she thought it would hold. The shaft opening was about a yard square, which would allow just enough room for her tank.

Gamay glanced at her wristwatch. “Going in,” she said.

Her supple body slithered over the lip of the opening and she disappeared into the square black hole. The tanks gonged against the sides, dislodging pieces of wood, but the shaft remained intact. Zavala watched the glow fade as Gamay descended.

“What’s it like down there?” Zavala said.

“Just like Alice in Wonderland down the Rabbit Hole.”

“See any rabbits?”

“Haven’t seen a damned thing—hello.”

Silence.

“Are you okay?” Zavala said.

“Better than okay. I’m out of the squeeze. I’m in a tunnel or cave. C’mon down. There’s a ten-foot drop after you exit the shaft.”

Zavala slid into the opening and joined Gamay in a chamber at the bottom of the shaft.

“I think this is a continuation of the boat cave,” Gamay said. “We’re on the other side of the rockslide.”

“No wonder the hotel management was upset. The river would have carried the kitchen slops into the boat cave.”

Zavala took the lead again. He swam into the cave, playing his flashlight beam on the walls. The rock formations disappeared after a few minutes.

“We’re in a mine,” he said. “See the chisel marks?”

“This could be the source of the gold that the hotel guests panned for.”

Zavala probed the darkness ahead his light. “Look.”

A tunnel opening had been cut in the wall to the left.

They left the main cave to explore the tunnel. The passageway was about ten feet high and six wide. A barrel ceiling arced overhead. Alcoves had been cut in the wall for torches.

After about a hundred yards, the tunnel intersected with another at a right angle. The discussion of their next step was short but intense. They could be dealing with a labyrinth. Without a lifeline, they could quickly lose their way. The limited amount of air in their tanks could make the wrong decision a fatal one.

“Your call,” Zavala said.

“The floor on the right-hand passageway is more worn than the others,” Gamay said. “I say we follow it for a hundred yards. If we don’t find anything, we’ll head back.”

Zavala crooked his forefinger and thumb in an okay signal, and they plunged into the passageway. They swam without talking to conserve air. Both were aware that each fluttering kick brought them closer to danger. But curiosity spurred them on until the tunnel ended, and they broke into the open after swimming about fifty yards.

The passageway had ended in a large chamber. The ceiling and opposite walls were beyond the range of their lights. They had come to the most hazardous part of their dive. It would be easy to become disoriented in a large open space. They decided to confine their exploration to no more than five minutes. Gamay would stay at the mouth of the tunnel. Zavala would do the actual exploration. At no time would one diver be out of sight of the other’s light.

Zavala struck out into the darkness, keeping close to the wall.

“Far enough. I’m losing you,” Gamay cautioned.

Zavala stopped.

“Okay. I’m swimming away from the wall. The floor is smooth. This room may have seen a lot of traffic. Nothing to indicate what it was used for.”

Gamay issued another warning. He turned back and homed in on her light. He followed a zigzag pattern that would cover the maximum about of ground.

“See anything yet?” Gamay said.

“Noth—wait!”

He swam toward an amorphous shape.

“You’re moving out of sight,” Gamay said.

Gamay’s beacon had become a smudged pinpoint. It would be suicide to proceed much farther, but Zavala couldn’t stop now.

“A couple more feet.”

Then silence.

“Joe. I can barely see you. Are you all right?”

Zavala’s excited voice came over the communicator. “Gamay, you’ve got to see this! Leave the torch to mark the tunnel and follow my light. I’ll wave it.”

Gamay estimated they had just enough air to navigate the tunnel, rise up the shaft, and make their way to the surface. “We don’t have much time, Joe.”

“This will only take a minute.”

Gamay was known to use salty language, but she kept her thoughts to herself. She placed the flashlight on the floor and swam toward the moving light. She found Zavala next to a circular stone dais about three feet high and around six feet in diameter. The surface of the platform was covered with rotten wood and pieces of yellow metal.

“Is that gold?” she said.

Zavala held a yellow piece of metal close to her mask. “Could be. But this caught my attention.”

In brushing away the wood, Zavala had exposed a metal box around a foot long and eight inches wide. Raised lettering on the top of the box was partially obscured by a black film, which came off with a wipe of Zavala’s glove. He murmured an exclamation in Spanish.

Gamay shook her head. “It can’t be,” she said.

But there was no denying the evidence of their eyes. A name was embossed on the box lid:

THOMAS JEFFERSON

Chapter 48

THE HORSE THUNDERED TOWARD the gorge like a runaway battle tank. Austin fought to stay in the saddle. He was top-heavy from his weapons and armor. One foot had slipped from a stirrup. His steel-encased head bounced like a bobble-head doll’s. His shield was sliding off his arm. The long lance pointed everywhere except where he wanted.

Val’s hooves clattered onto the metal bridge. Through the eye slits, Austin caught a blurred glimpse of a gleaming spear tip and the bull’s-head emblem on Baltazar’s tunic. Then the horses were off the bridge and back on the grassy turf.

Austin let out the breath he’d been holding and tightened the reins. He slowed the horse and brought it around to face Baltazar, who was on the other side of the gorge calmly watching Austin’s disarray. Baltazar lifted the helmet from his head and held it in front of his chest.

He shouted: “Good joust, Austin. But you seem to be having some trouble keeping things together.”

Laughter rippled through the crowd of onlookers.

Austin removed his helmet and wiped the sweat from his eyes with the back of his mailed glove. He ignored the pain from his half-healed rib wound and called back in defiance. “I was distracted by thoughts of my new Bentley.”