Pitt steered the Zodiac toward the shore, angling to one side of the cove before killing the motor a few yards from the surf line. Dirk tossed an anchor over the side to secure their position, then the threesome slid into their dive gear.
'We'll run parallel to shore as close to the surf line as we can get,' Pitt instructed. 'Just watch out for the breakers.'
'And what exactly are we looking for?' Dirk asked.
'A stairway to heaven.' His father smiled cryptically, then pulled his mask down over his face. Sitting on the edge of the boat, he leaned over backward and dropped into the water, disappearing under a small wave. Dirk and Summer quickly adjusted their masks and regulators, then followed him over the side.
They converged on the bottom, less than twenty feet below, in water that was dark and turbid. The crashing surf roiled the water with foam and silt, reducing the visibility to just a few feet. Summer saw her father nod at her then turn and head into the murk. She quickly followed behind, knowing her brother would take up the rear.
The bottom surface was a bed of craggy black lava that rose up sharply to her left. Even underwater, she was pushed strongly from the side by the incoming waves and she frequently turned seaward and kicked hard with her fins to avoid being body-slammed into a rising mount of lava.
She followed her father's fins and trail of bubbles for twenty minutes before he finally disappeared for good into the dark waters ahead of her. She figured they were roughly halfway across the cove's landfall shore. She would swim another ten minutes, she decided, then surface and find out exactly where she was.
Following the surf line, she felt herself being carried close to a lava rise by a large wave. Turning to kick away, she was surprised by a second, more powerful wave, which pushed her forcefully toward shore.
The wave quickly overpowered her, and she slammed backward into the lava wall, her steel air tank grinding against the rock.
Unhurt by the collision, she remained pinned against the lava until the wave rolled past. She started to move away when she noticed a dark spot on the rocks above her head. Pulling herself closer, she peered into a black tube that angled slightly upward and toward the shore line. She couldn't tell in the murky water whether it was just a hole in the rocks, so she pulled out a flashlight and reached inside. The beam of light faded in the water, not detecting an opposing wall to reflect. The opening clearly traveled for some distance.
Her heart skipped a beat as she realized that this was what her father was searching for. She braced herself by the opening as another large wave passed by, then reached around and banged the flashlight against her dive tank. A metallic clanging echoed through the water.
Almost immediately Dirk appeared, looking at Summer quizzically, then eyeing the opening with surprise as she pointed the way. A minute later her father swam up, playfully patting Summer on the head after spotting the tunnel. Flicking on his own flashlight, he swam into the tube, his kids following behind.
Pitt immediately recognized the opening as a lava tube. Its cylindrical-shaped walls were almost perfectly formed, rounded and smoothed as if made by a machine. But the passage was actually the result of a steady flow of hot lava cooling on the surface and creating an outer crust. The liquid center ultimately flowed out, leaving a hollow tube. Lava tubes have been found that stretch fifty feet wide, while a few run several miles long. Summer's tube was relatively small, stretching about six feet in diameter.
Pitt followed the tube for thirty feet, noticing a gradual ascent on his depth gauge. The tube suddenly flared wide, and he noticed a reflection from his flashlight just before his head broke the surface of a calm pool of water. Bobbing on the surface, he turned the light around him. Steep black walls of lava fell vertically to the water on three sides. The fourth side, however, opened to a wide, rocky clearing. Pitt kicked lazily toward the landing as the underwater lights of Summer and Dirk surfaced near him. They all swam to the rocks and climbed out of the water before anyone spat out their regulators and spoke.
'It's amazing,' Summer said. 'An underground cavern fed from a flooded lava tube. Though it could use a little air-conditioning.' The air in the cave was dank and musty, and Summer contemplated keeping her tank and regulator on.
'It was likely a much deeper cave at one time, but became sealed off by the lava flows gushing down the mountainside,' Pitt said. 'It's a fluke that a lava tube happened to form at its entrance.'
Dirk dropped his tank and weight belt, then flashed his light around the clearing. Something caught his eye in the rocks.
'Summer, behind you.'
She turned and gasped at the sight of a man standing just a few feet away. She stifled a cry at realizing that the man wasn't real.
'A clay warrior?' Dirk asked.
Summer shined her light and noticed another figure standing nearby. They were both life-sized figures, with painted uniforms and sculpted swords. Summer crept closer, eyeing the artisans' detail. They were soldiers, and each had braided hair, and a stringy mustache beneath almond-shaped eyes.
'Emperor Qin's terra-cotta warriors of Xian?' Pitt said. 'Or perhaps a thirteenth-century facsimile.'
Summer looked at her father quizzically. 'Thirteenth century? What are they doing here?'
Pitt stepped up to the two figures and noticed a small path that ran between them, cut through the lava.
'I think they are guiding us to the answer,' he said. Stepping between the clay sculptures, he followed the path, with Dirk and Summer in tow. The worn trail twisted around several walls of lava, then suddenly opened into a wide, cavernous room.
Pitt stood at the threshold with his two children, shining their flashlights in awe. The huge chamber was filled with an army of clay figures flanking the walls. Each wore a heavy necklace of gold or an amulet studded with gemstones. Positioned inside the clay warriors was another ring of sculptures, mostly scale figures of animals. Some were carved jade or stone, while others were gilded with gold. Deer grazed fearlessly next to large falcons. A pair of prancing white mares was showcased near the center of the room.
Interspersed with the sculptures were dozens of small lacquered cabinets and tables covered in dust. On a large teak table, Summer noticed an elaborate place setting that shone under her light. The plates, flatware, and goblets sitting atop a silk mat were all cast in gold. Adjacent to the table was an assortment of silver and gold ornaments, some adorned with Arabic lettering and literary Chinese script. Other tables held mirrors, boxes, and art objects glistening with decorative gemstones. Summer crept to a nearby cabinet covered with scenes of battle painted in bright colors and pulled open a drawer. Inside, trays of amber, sapphires, and rubies filled the silk-lined case.
The sculptures and jewels didn't interest Pitt. He stared past the artifacts toward the centerpiece of the entire chamber. On a raised stone platform in the middle of the room stood a long wooden box. It was painted bright yellow and featured detailed carvings on each panel. Pitt stepped closer and shined his light at the top of the box. A stuffed cheetah, its teeth bared and a clawed paw scratching the air, seemed to hiss back at Pitt. He lowered his light to the top surface of the box and smiled at the image. A large wolf, painted blue, was emblazoned across the surface.
'May I present the late emperor of the Yuan Empire, Kublai Khan,' he said.
'Kublai Khan,' Summer whispered in reverence, her eyes wide. 'It can't be.'
'I thought he was buried somewhere near Genghis,' Dirk said.
'According to popular legend. But the tale just didn't seem to add up. Borjin was able to locate the grave of Genghis Khan with his seismic device, but he never found Kublai. They should have been buried in the same ballpark. Then your Dr. Tong appears here, sidestepping a mission to disrupt the Alaska Pipeline in order to visit a shipwreck? There was obviously a greater draw, something only the Borjins could appreciate. I suspect they may have found an empty tomb for Kublai in Mongolia, or discovered some other clue that he was buried elsewhere.'
'I still don't see how that leads here,' Summer said.
'The story is in the cheetah skin. It was discovered at Shang-tu, so it had an original link with Kublai.
The emperor was known to possess trained cheetahs used for hunting, so the skin may have even come from one of his pets. More relevant was that the cheetah skin was unearthed together with a silk map that purportedly showed the location of Genghis Khan's tomb. Borjin's father acquired the silk map, and Borjin himself admitted that it helped lead to the grave site. For some reason, the significance of the cheetah skin paintings was overlooked when first found. The blue wolf was the trigger for me.'
