"Still no sign of bodies?"
"Not yet."
Pitt began to feel an icy finger trail up the nape of his neck as he spotted a skeleton with a bony hand pointing into the gloom. Beside the rib cage was a rusty breastplate, while the skull was still encased in what he guessed was a sixteenth-century Spanish helmet.
Pitt reported the sighting to Giordino. "Tell Doc Miller I've found a long-dead Spaniard complete with helmet and breastplate down here." Then, as if drawn by an unseen force, his eyes followed in the direction a curled finger of the hand pointed.
There was another body, one that had died more recently. It appeared to be a male with the legs drawn up and the head tilted back. Decomposition had not had time to fully break down the flesh. The corpse was still in a state of saponification, where the meaty tissue and organs had turned into a firm soaplike substance.
The expensive hiking boots, a red silk scarf knotted around the neck, and a Navajo silver belt buckle inlaid with turquoise stones made it easy for Pitt to recognize someone who was not a local peasant. Whoever he was, he was not young. Strands of long silver hair and beard swayed with the current from Pitt's movements. A wide gash in the neck also showed how he had died.
A thick gold ring with a large yellow stone flashed under the beam of the dive light. The thought occurred to Pitt that the ring might come in handy for identifying the body. Fighting the bile rising in his throat, he easily pulled the ring over the knuckle of the dead man's rotting finger while half expecting a shadowy form to appear and accuse him of acting like a ghoul. Disagreeable as the job was, he swished the ring through the silt to clean off any remnant of its former owner, and then slipped it onto one of his own fingers so he wouldn't lose it.
"I have another one," he notified Giordino.
"One of the divers or an old Spaniard?"
"Neither. This one looks to be a few months to a year old."
Do you want to retrieve it?" asked Giordino.
"Not yet. We'll wait until after we find Doc Miller's people-" Pitt suddenly broke off as he was struck by an enormous force of water that surged into the pool from an unseen passage on the opposite wall and churned up the silt like dust whirling around a tornado. He would have tumbled out of control like a leaf in the wind by the unexpected energy of the turbulence but for his safety line. As it was he barely kept a firm grip on his dive light.
"That was a hell of a jerk," said Giordino with concern. "What's going on?"
"I've been struck by a powerful surge from nowhere," Pitt replied, relaxing and allowing himself to go with the flow. "That explains why the silt layer is so shallow. It's periodically swept away by the turbulence."
"Probably fed by an underground water system that builds up pressure and releases it as a surge across the floor of the sinkhole," Giordino speculated. "Shall we pull you out?"
"No, leave me be. Visibility is nil, but I don't seem to be in any immediate danger. Slowly release the safety line and let's see where the current carries me. There must be an outlet somewhere."
"Too dangerous. You might get hung up and trapped."
"Not if I keep from entangling my safety line," Pitt said easily.
On the surface, Giordino studied his watch. "You've been down sixteen minutes. How's your air?"
Pitt held his pressure gauge in front of his face mask. He could barely read the needle through the maelstrom of silt. "Good for another twenty minutes."
"I'll give you ten. After that, at your present depth, you'll be looking at decompression stops."
"You're the boss," Pitt came back agreeably.
"What's your situation?"
"Feels like I'm being pulled into a narrow tunnel feet first. I can touch the walls closing around me. Lucky I have a safety line. Impossible to swim against the surge."
Giordino turned to Miller. "Sounds as if he may have a lead on what happened to your divers."
Miller shook his head in anger. "I warned them. They could have avoided this tragedy by keeping their dive in shallow depths."
Pitt felt as though he was being sucked through the narrow slot for an hour when it was only twenty seconds. The silt cloud had faded slightly, most of it remaining in the deep pool behind. He began to see his surroundings more clearly. His compass showed he was being carried in a southeasterly direction. Then the walls suddenly opened out into one enormous, flooded room. To his right and below he caught the momentary flash of something glinting in the murk. Something metallic vaguely reflecting the silt-dimmed beam of his dive light. It was an abandoned air tank. Nearby was a second one. He swam over and peered at their pressure gauges. The needles were pegged on empty. He angled his dive light around in a circle, expecting to see dead bodies floating in the darkness like phantom demons.
The cool bottom water had drained away a measure of Pitt's strength and he could feel his motions becoming sluggish. Although Giordino's voice still came through the earphones as clearly as if Pitt was standing next to him, the words seemed less distinct. Pitt switched his mind off automatic and put it on full control, sending out instructions to check data gauges, safety line, and buoyancy compensator as if there were another Pitt inside his head.
He mentally sharpened his senses and forced himself to be alert. If the bodies were swept into a side passage, he thought, he could easily pass them by and never notice. But a quick search turned up nothing but a pair of discarded swim fins. Pitt aimed the dive light upward and saw the reflective glitter of surface water that indicated the upper dome of the chamber contained an air pocket.
He also glimpsed a pair of white feet.
Trapped far from the outside world in a prison of perpetual silence, breathing in a small pocket of air millions of years old and lying smothered in total blackness deep under the earth is too alien, too terrible to imagine. The horror of dying under such terrifying conditions can provide nightmares on a par with being locked in a closet full of snakes.
After initial panic had passed and a small degree of rationality was retrieved, any hope that Shannon and Rodgers had of surviving vanished when the air in their tanks became exhausted and the final spark of life in the batteries of their dive lights gave out. The air in the small pocket soon became foul and stale from their own breathing. Dazed and lightheaded from lack of oxygen, they knew their suffering would only end when the watery chamber became their tomb.
The underground current had sucked them into the cavern after Shannon had excitedly dived to the bottom of the sinkhole after glimpsing the field of bones. Rodgers had faithfully followed and exhausted himself in a frantic effort to escape the surge. The last of their air had been used up in a vain attempt to find another passage leading out of the chamber. There was no exit, no escape. They could only drift in the blackness, held afloat by their buoyancy compensators, and wait to die.
Rodgers, for all his guts, was in a bad way, and Shannon was just hanging on by a thread when suddenly she noticed a flickering light in the forbidding water below. Then it became a bright, yellow beam stabbing the blackness in her direction. Was her numbed mind playing tricks? Did she dare entertain a glimmer of hope?
"They've found us," she finally gasped as the light moved toward her.
Rodgers, his face etched and gray with fatigue and despair, stared blankly down at the approaching light beam without reaction. The lack of breathable air and the crushing blackness had left him in a near comatose state. His eyes were open and he was still breathing, and, incredibly, he still tightly grasped his camera. He felt a vague awareness that he was entering the tunnel of light described by people who returned from death.
Shannon felt a hand grab her foot, and then a head popped out of the water less than an arm's length away. The dive light was beamed into her eyes, momentarily blinding her. Then it moved onto Rodgers's face. Instantly recognizing who was the worse off, Pitt reached under one arm and took hold of an auxiliary air regulator that was connected to the dual valve manifold of his air tanks. He quickly slipped the mouthpiece of the regulator between Rodgers's lips. Then he passed Shannon a reserve pony bottle and air regulator that was attached to his waist belt.
Several deep breaths later, the revival in mood and physical well-being was nothing short of miraculous. Shannon gave Pitt a big bear hug as a renewed Rodgers pumped his hand so vigorously he nearly sprained Pitt's wrist. There were moments of speechless joy as all three were swept away in a euphoria of relief and excitement.
Only when Pitt realized that Giordino was shouting through his earphones, demanding a situation report, did he announce, "Tell Doc Miller I've found his lost lambs. They are alive, repeat, they are alive and well."
"You have them?" Giordino burst through Pitt's earphones. "They're not dead?"
"A little pale around the gills but otherwise in good shape."
"How is it possible?" muttered a disbelieving Miller.
Giordino nodded. "The Doc wants to know how they stayed alive."
"The current swept them into a chamber with an air pocket in its dome. Lucky I arrived when I did. They were minutes away from using up the oxygen."
The crowd grouped around the amplifier was stunned by the announcement. But as the news sank in, relief spread across every face, and the ancient stone city echoed with cheers and applause. Miller turned away as if wiping tears from his eyes while Giordino smiled and smiled.
Down in the chamber Pitt motioned that he could not remove his full face mask and converse. He indicated they would have to communicate through hand signals. Shannon and Rodgers nodded, and then Pitt began to describe visually the procedure for their escape.
Since the lost divers had dropped all of their useless dive gear, except for face masks and buoyancy compensators, Pitt felt confident the three of them could be pulled back through the narrow shaft against the current and into the main pool by his phone and safety line without complications. According to the manufacturers' specs, the nylon line and phone cable could support up to almost six thousand pounds.
He signaled Shannon to wrap one leg and one arm around the line and lead off, breathing through her pony bottle. Rodgers would repeat the step and follow, with Pitt bringing up the rear close enough for the spare regulator to reach Rodgers's mouth. When Pitt was sure they were stable and breathing easy, he alerted Giordino.
"We're positioned and ready for escape."
Giordino paused and stared at the young archaeology students, their hands gripping the safety line, poised as if ready for a tug-of-war. He studied their impatient expressions and quickly realized he would have to keep their enthusiasm and excitement in check or they might haul the divers through the rock passageway like so much meat through a jagged pipe. "Stand by. Give me your depth."
"I read slightly over seventeen meters. Much higher than the bottom of the sinkhole. We were sucked into a passage that sloped upward for twenty meters."
"You're borderline," Giordino informed him, "but the others have exceeded their time and pressure limits. I'll compute and advise you of decompression stops."
"Don't make them too long. Once the pony bottle is empty, it won't take long for the three of us to use up what air I have left in my twin tanks."
"Perish the thought. If I don't hold these kids by the collar, they'll jerk you out of there so fast you'll feel like you were fired from a cannonball."
"Try to keep it civilized."
Giordino held up his hand as a signal for the students to begin pulling. "Here we go."
"Bring on the jugglers and the clowns," Pitt answered in good humor.
The safety line became taut and the long, slow haul began. The rush of the surge through the shaft was matched by the gurgling of their exhaust bubbles from the air regulators. With nothing to do now but grip the line, Pitt relaxed and went limp, allowing his body to be drawn against the flow of the underground current that gushed through the narrow slot like air through a venturi tube. The lighter silt-clouded water in the pool at the end of the passage seemed miles away. Time had no meaning, and he felt as if he'd been immersed for an age. Only Giordino's steady voice helped Pitt keep his grip on reality.
"Cry out if we haul too fast," ordered Giordino.
"Looking good," Pitt replied, hearing his air tanks grinding against the ceiling of the shaft.
What is your estimate of the current's rate of speed?"
"Close to eight knots."
Small wonder your bodies are causing severe resistance. I've got ten kids up here, pulling their hearts out."
"Six more meters and we're out of here," Pitt informed him.
And then a minute, probably a minute and a half, struggling to hold on to the safety line as they were buffeted by the diminishing force of the torrent, and they broke free of the shaft into the cloud of silt swirling around the floor of the sacrificial pool. Another minute and they were pulled upward and clear from the drag of the current and into transparent, unclouded water. Pitt looked up, saw the light filtering through the green slime, and felt a wondrous sense of relief.
Giordino knew they were free of the suction when the tension on the safety line suddenly diminished. He ordered a halt to the ascent operation as he rechecked his decompression data on a laptop computer. One stop of eight minutes would take Pitt out of any danger of decompression sickness, but the archaeology project divers would need stops of far longer duration. They had been down over two hours at depths ranging from 17 to 37 meters (67 to 122 feet). They would require at least two stops lasting over an hour. How much air was left in Pitt's tanks to sustain them? That was the life-or-death dilemma. Enough for ten minutes? Fifteen? Twenty?
At sea level, or one atmosphere, the normal human body contains about one liter of dissolved nitrogen. Breathing larger quantities of air under the pressure of water depth increases the absorption of nitrogen to two liters at two atmospheres (10 meters, or 30 feet of water depth), three liters at three atmospheres (30 meters, or 90 feet), and so on. During diving the excess nitrogen is rapidly dissolved in the blood, carried throughout the body, and stored in the tissues. When a diver begins to ascend, the situation is reversed, only this time far more slowly. As the water pressure decreases, the overabundance of nitrogen travels to the lungs and is eliminated by respiration. If the diver rises too quickly, normal breathing can't cope and bubbles of nitrogen form in the blood, body tissue, and joints, causing decompression sickness, better known as the bends, a condition that has crippled or killed thousands of divers over the past century.