Pressure Drop (38 page)

But unofficially everyone knew that caves do kill people. In open water a diver can easily kill himself too, but at least when trouble strikes he can usually manage to start going up before he dies. In a cave he has to get out first. Cave diving was the most dangerous sport Matthias knew—more dangerous than boxing, hang-gliding, bullfighting, bear wrestling. The reward was the chance to experience the fun and esthetic pleasure of coal mining. Matthias kicked his way along the tunnel.

It began doing the things cave tunnels do: it widened, narrowed, divided in two. Matthias checked his compass. One tunnel led in a northern direction, at least as far he could see with his torch. He paused before it, completely still, and felt no current on the skin of his face. The second tunnel led due east. That was the right direction; he also felt water flowing weakly around him, gentle as a summer breeze. The thought made him smile and he looked at his depth gauge: 155. Not deep enough for him to feel the effects of nitrogen narcosis; more accurately, he'd never been narced at that depth before. So why was he smiling? Matthias stopped smiling.

He tied off at the dividing point, looping his line around a limestone spur sticking out from the wall. He checked his air: 2400 p.s.i. No sweat, as his commander in Panama City had liked to say. One-third in, one-third out, one-third in reserve. Matthias caught a handhold inside the eastern tunnel, pulled himself in. He felt the line at his waist, made sure it was unreeling. The nylon line beat Hansel's bread crumbs, but not by much. His commander had used one too, but that hadn't stopped him from disappearing one day in the maze under Warm Mineral Spring.

Matthias swam along through the cone of yellow light. He found himself thinking about the day Danny was born. It was too Freudian, but he thought about it anyway. He was thinking about it so hard that he almost missed the cave that opened up on his left. He paused and shone his light inside. The beam touched the far wall, about thirty feet away. A few stalactites hung from the ceiling and dark silt covered the floor. Matthias fanned his free hand through it. The silt rose quickly, muddying the water. He stuck his hand in up to the shoulder without reaching the limestone floor. But his fingers brushed something. He grasped it and backed out into the tunnel.

It was a military boot, well preserved. The silt would have protected it from the decaying effects of oxygen: it could have been there for a month, a year, a generation. The boot was laced to the top, knotted and bowed. He scraped it clean with his fingernails, then turned it over to see if there was anything written on the sole. There wasn't, but little bones fell out of the boot top and drifted like feathers to the cave floor.

Matthias tied the boot to his line and checked his air pressure: 1650. Then he moved on. His compass pointed east. His depth gauge read 80 feet. That surprised him. He was going up. The tunnel inclined to 70 feet before it dipped back to 80, then beyond—90, 100, 110. At 130 feet it leveled out, but quickly narrowed. Rubble covered the floor. It grew thicker, driving Matthias up to the ceiling. He squeezed along until he could move no farther. Rubble filled the tunnel, except for an opening at the top, just big enough to stick his fist in. He stuck his fist in, felt nothing, withdrew it. Was it the end of the tunnel or a rock fall? And if a rock fall, how extensive? Matthias pointed his light at the small opening. A baby nurse shark came swimming through, the first living thing Matthias had seen in the cave. It turned away from the light and swam back into the hole. Matthias considered the implications of its presence, then began pulling quickly at the topmost rocks. They came away, rolled down the rubble pile. Matthias slipped over the top and down the other side.

There was no sign of the nurse shark. The tunnel stretched ahead, widening slightly in the beam of his light, continuing beyond. Matthias swam on, but less than a minute later he felt a slight tug at his waist, glanced down and saw that he had come to the end of his line. He checked the time: he'd been down for twenty-five minutes; pressure: 1100. Depth: 120. Air one-third gone, out of line, still going in. He found himself smiling again. This was cave diving. Nothing went right.

Matthias unclipped the reel and jammed it between a cut-off stalagmite and the left-hand wall. Then, lineless as the silliest amateur whose body had never been recovered, he kicked on.

He swam quickly now. The tunnel grew to the width of a suburban garage. Matthias kicked harder, not even taking the time to read his pressure gauge. Then all at once the walls, the ceiling, the floor all vanished. It was as though he had stepped off the edge of the Grand Canyon, except he wasn't falling. He shone his light: behind him, and saw the opening of the tunnel he had come out of; overhead, and saw a great rocky dome arching high above. He swung the beam down. It barely reached the opposite wall. His eyes followed the yellow circle along the wall's face. Down, down it went, at least one hundred feet, to the limit of the light's range, and beyond. Matthias aimed the torch straight between his fins. It illuminated a long yellow column of clear water and no sign of the bottom. He was in an enormous underwater chamber, somewhere beneath Andros, or possibly beneath the seabed of Zombie Bay. His heart beat a little faster. That was bad. He took a few even breaths to slow it. Then he checked the depth—150—and started down.

He spiraled slowly all the way, shining his light around him. He saw black caves in the walls, bare ledges, white limestone columns. But he didn't see the bottom. He hit 200 feet, 220, 230. At that depth he was sucking up ten pounds of air with every breath. There was something he should be doing, but what was it? Something Freudian? Matthias smiled and almost lost his mouthpiece. He squeezed the rubber between his teeth, muttered, “Christ,” and kicked harder.

Two-hundred-and-eighty feet. Two-ninety. Three-hundred. He paused. Three-hundred feet under and seven- or eight-hundred feet in was a good place for pausing. He smiled again. He was very witty today, down in the cave. A witty caveman. All at once, he wished there was a woman waiting for him when he came out. The wish was so strong it brought tears to his eyes. He was thinking of wiping them away when he remembered he was wearing a mask.

Narced. Matthias grabbed his pressure gauge. That's what he'd been trying to think of. Check the air: 100 p.s.i. As soon as he saw the number his air started to pull hard. He breathed the last of it and switched to the second tank. Three-hundred feet down. Seven or eight-hundred from the blue hole. “Step one,” his old commander had said, “get narced. Step two, get bent. Step three, get buried, if they ever find you.”

Get out
. Matthias swept his beam into the depths for one last look. And this time he saw the bottom: a cone-shaped pile of rubble, boulders and other objects he couldn't identify. “Christ,” he said again, because he knew he should get out. But he went down instead.

Matthias had never dived deeper than 310. Few people did. Fewer returned. Three-hundred feet was the theoretical limit for compressed air. After 300 there was more to worry about than nitrogen. Oxygen itself became poisonous. Matthias went down. He hit 320, 330, 340. He felt like a little bird flying in a big night sky, a hidden picture of grace. He did a long slow somersault, wishing that the woman who wasn't waiting by the edge of the blue hole could see it. He was thinking of doing another one for her when he noticed things on the rubble pile, metal things: twisted hunks of rent and rusting steel plate. He checked the depth several times, but the numbers wouldn't register in his mind. He went deeper, and could now make out the rivets. A little deeper, and he saw a big cylinder wedged between two boulders. Deeper still, and he realized it was a submarine conning tower. He hovered above the top of the pile. He was about to check the depth when he saw something white in a silty depression. He couldn't look at two things at once, so he forgot about the depth gauge. He picked up the white object. It was a human skull.

Time passed. Christ, did it really? Matthias found himself staring into the empty sockets of the skull. How long had he been doing that? He dropped the skull.
Get going
. But he didn't get going. He watched the skull waft down on the pile, saw it roll past a few other skulls and some bones and out of sight.

Get going
.

Matthias took his first kick toward the surface. Then his torch imploded. His retinas retained a lingering yellow image of the rubble pile. It quickly faded to blackness. He could see nothing: not his compass, not his depth gauge, not his pressure gauge, not up, not down.
Don't panic. Panic equals death
. Matthias didn't panic. He breathed slowly, regularly. But that didn't mean he remembered his second torch right away. And when he did remember it, he wasn't sure where it was. He felt around his body, finally locating it on the back of his weightbelt. He spent some time unclipping it, finding the switch. He pressed it. The light shone in his face, blinding him. He turned it around, felt it slipping from his grasp, held on. He aimed the beam above his head and saw the rubble pile, not far above him. He was upside down. He reversed himself and kicked up.

At 320 feet he glanced at his pressure gauge: 1900. He was on the last third, his reserve. He should have been out by now, but he was in, deep in. “Going to die, pal,” he said, or thought he said. Then he saw something in the east wall of the chamber: a big black cave mouth with a wide ledge sticking out in front. A suitcase lay on it, a few yards from the edge. Matthias swam over, grabbed it and started up, kicking, kicking. His heart was beating fast again, but there was nothing he could do about it. 300, 280, 250, 200. He was coming up too fast, but he didn't look at his gauges or his watch. His gaze was on the west wall. Where was the opening? Hadn't it been at 200? He rose above the 200-foot point. 175. Had he missed it? Would he go all the way to the dome and end up as one of those cave divers who tried to claw his way out? No one would ever know.

Then he saw the opening, a little farther up. He swam into it and kicked hard. His mind began to clear. What was ahead? The end of the reel, the rubble pile, the cave with the boot. It didn't matter. Once he reached the line he was home, if his air lasted. He glanced at the gauge: 950.

Ahead the tunnel narrowed, as he remembered. Then it divided. He didn't remember that at all. The tunnel divided, but at a sharp angle; the division had been at his back on the way in and he had missed it. Matthias stopped, flashed his light in both entrances. They looked the same. But one led back to the blue hole and the other led nowhere. Air pressure: 600. He had to be right the first time. He forced himself to be still, hoping to feel a current entering either tunnel. He felt nothing. Shouldn't the tide be flowing by now? Perhaps there was some other phenomenon at work in the cave. Was that it, or had he already made his mistake and entered the wrong tunnel coming out of the domed chamber?

Decide
. Matthias shone his light into the two tunnels again, hoping to see anything that might differentiate them. There was nothing. He closed his eyes, trying to will the right answer into his consciousness. Because of that, he almost missed the baby nurse shark swimming out of the right-hand tunnel. Matthias turned into it and swam as fast as he could.

He went past the reel without noticing it, so wasn't sure he was right until his light picked out the line running along the right-hand wall. Was it his imagination or was his air just beginning to pull hard? He didn't check the gauge because there was no time and he didn't want to know. The suitcase slowed him down, but he wouldn't let it go. He dragged it over the rubble pile, passed the cave where he had found the boot, reached the second tie-off. He started skip breathing, sucking at his regulator, receiving a grudging breath of air and holding it in. Skip breathing meant risking death by embolism, if the tunnel was going up. Not skip breathing meant running out of air.

Matthias breathed out, breathed in, kicked. He went by the first tie-off. Ahead lay the manhole-sized opening. He shoved the suitcase through, squeezed past after it, swam up through the sloping cave entrance, letting out his breath, and into the blue hole.

Matthias stopped kicking and rose very slowly. Plenty of air left: three or four lungfuls. No sweat, commander. He went up through the red layer and into the light.

His spare tanks lay where he had left them, in the niche at 50 feet. He laid the suitcase on the ledge, doffed his backpack and put it beside the suitcase, opened the valve on the spare tanks and donned them. Then he stuck the regulator in his mouth, breathed out the last breath from the old tanks, sucked in the first one from the new. Air flowed smoothly through the regulator. Perfect. Plan your dive, as every beginner was told, and dive your plan.

Matthias hovered beside the ledge, breathing. For a while that was all he did. Later he looked up at the blue glow above. He breathed and gazed at the blue. That was nice.

Matthias took the decompression tables out of the pocket in his BC. He studied them for a few minutes but they weren't much help: they stopped at 300 feet. He tried to recall the deepest reading on the gauge. 320? 340? Then he recalled that he hadn't checked the gauge at the deepest point. Matthias dropped down to 70 feet. He decompressed there in the darkness for ten minutes, then moved up to 60 for ten more. After that, he returned to 50, and fifteen minutes later rose to 40. Then 30, then 20, then 10. His air began pulling harder. He wished he had brought another spare. But he hadn't, and all he could do was breathe the tank empty and go up.

A few minutes later, he sucked the last mouthful of air out of the tank and finned slowly toward the surface, breathing out all the way. His body didn't twist and bend, he didn't lose control of his legs, nothing stabbed his spine, his shoulders or his hips, his fingertips didn't prickle, his eyelids didn't itch. That meant no nitrogen bubbles were fizzing through his bloodstream: he wasn't bent. A lucky man.