TWENTY-ONE
ABOUT HALFWAY THROUGH THE TUNNEL, am Ende could not help stirring up silt as the sump’s bottom rose. Stone lost sight of the guideline. He tried to surface to orient himself but found no airspace, only rock ceiling with water all the way up. Without a millimeter of free space, he was in a complete silt-out.
Stone knew standard procedure for locating a lost guideline. Cave divers carry a “gap reel”—a spare reel loaded with line. If they lose contact with the main guideline, they tie the gap line off to any available contact point and swim back and forth in widening arcs until they hit the main line. Tying off to that, they swim back to untie their gap line, then return to the main guideline, reeling up the gap line as they go.
But Stone could not find his gap reel. In fact, he had left it at Camp 5, a predicament that would have shoved many divers over the line from stress to panic. But the rebreather, which might have taken one life, now saved another. Stone’s large body needed a lot of air. Had he been using conventional scuba tanks, especially with accelerating heart rate and respiration, he might well have run out of air too soon. But his rebreather gave him hours of dive time, making all the difference. Relax, he told himself. You’ve got time to think this through.
He methodically worked out a plan that would make good use of a God-given gift: his six-foot, four-inch height. If he spread his arms and legs wide, the additional twenty-four inches of his fins would create a fingertip-to-fintip span of more than ten feet. Deflating his buoyancy vest, he floated down in a skydiver’s spread-eagle position and hit the guideline with a fin on his first try. Grabbing hold, he followed the line to the end of the sump. Am Ende was already there, waiting for him on a gravel beach.
Not a good time to freak her out, he thought. He took her hand and said, “Very nicely done;” he made no mention of his narrow escape.
They established Camp 6, where they would spend their first night, on a gravelly hill 300 feet beyond the sump. (“Camp” was mattresses made by putting their two wet suits into plastic garbage bags.) Then they confronted an excruciating decision: what to do with the rebreathers, their sole hope of escape from the cave. Having dived their way through the two sumps, there was no way they could free-dive their way back. Their survival depended on functioning rebreathers.
Am Ende’s rebreather had already suffered that one malfunction during Rolland’s dive on March 25, the day before his death, when it exhausted its carbon dioxide scrubber prematurely. That failure, plus a punctured bladder on Bill’s unit and the two problems with am Ende’s at Camp 5, had amply demonstrated that these may have been marvels of invention, but with hundreds of delicate parts and space-age electronics, they were far from invulnerable.
The fact was that every time they moved the rebreathers, powered them up and shut them down, or submerged and resurfaced, they increased the probability of malfunction. Beyond their camp, they saw a number of dry passages, so diving was not their only option for going forward, at least initially. They finally decided that they would do no further diving on the rebreathers until it was time to return through the sumps, both to protect them from damage and to leave them with the maximum reserves of breathing gas. After powering them down, they cached them on a rock outcropping as high as they could, hoping that if—no, when—the rains of summer began, whatever flow resulted would not be high enough to carry the rebreathers away. Of course, if flow that high came roaring through, it would wash both of them away like corks in a sewer main as well.
The rains of summer. They were now playing a Mexican cave version of Russian roulette with those rains, which were notoriously fickle. The rains might come in weeks, or days, or even hours. No one could say for sure. But when they did arrive, the cave would flood. And it was easy for them to envision how they would die if that happened, because something similar already had.
Two weeks earlier, on April 16, a rainstorm had struck. It lasted just three days, but this early storm gave a preview of what floods could do, raising river levels in surface canyons six feet, sending torrents roaring down into Huautla. In the cave, meandering streams became whitewater rivers, and dry vertical pitches morphed into lethal waterfalls.
The floods trapped a National Geographic photo team and a few others at Camp 3. Most were seasoned explorers, inured to the trials of supercaving. Still, after two days and nights of confinement, it became hard not to envision a wall of water blasting through the great chamber, washing them all down into the cave like bugs in a toilet. After three days and nights, the imprisonment became too much and they bolted for the surface. It was a bad decision. During the attempt, Steve Porter nearly drowned twice before they had gone a half mile, at which point everyone hustled back to Camp 3, wetter but wiser. Eventually all returned safely to the surface, but the cave had made its point. Am Ende and Stone’s chances of escaping after significant rainfall would be slimmer, because they were so much deeper and would feel the full force of the endless rainy season downpours.
Am Ende and Stone knew about what had happened to the group at Camp 3. They also knew that the beginning of rainy season fluctuated from year to year. They understood, as well, that they were at the bottom of a 6-mile-long drainage system that would collect water from the entire surface region and funnel it right toward them. If it rained while they were underground, it would be a fatal disaster.
As it turned out, their first disaster was caused not by rain but by light. Or, rather, by its absence. Standing atop a boulder in an immense breakdown pile just beyond Camp 6, am Ende took off her helmet to tighten the headband. Her carbide lamp fell out of its helmet mount and dropped down between the boulders at her feet. Light was a finite resource here, more important than water or food.
Stone was in another area, drawing in his notebook. “We have a problem here,” she called. He came over and she explained.
At first Stone didn’t believe her: “You’re pulling my leg.”
Am Ende assured him she was not. He peered down at the pile of rocks. “Down there? Can you see it?”
She shook her head. “Maybe you can reach it …”
Stone gave her his helmet, which had its own carbide lamp attached, and flopped down onto the pile of boulders. The spaces between them were small, but his lifetime of worming and squirming that six-four frame through viselike squeezes helped. Forcing his face and shoulders down into one crack, he worked his right hand, with a flashlight, into another. The brass lamp shone in his flashlight beam, 10 feet deeper. It was perched right at the lip of a small ledge. One clumsy brush would send it clattering down into the depths, lost forever. He stretched to his limit, but his fingertips were still at least 5 feet short of the lamp. “I can see it, but I can’t reach it,” he reported.
He pulled himself out of the cracks. Just as he did so, he heard am Ende exclaim, “Damn, not again!”
“What’s wrong? What are you doing?”
She had been standing by in the dark, flashlight off to conserve batteries. “I was drying out the felt in your lamp,” she said miserably. Never the useless bystander, am Ende had taken Stone’s own carbide lamp apart to dry out its wick. As she worked by feel in the dark, saving those precious batteries, the unthinkable had happened. She’d dropped Stone’s igniting mechanism, an assortment of tiny parts—flint, wheel, striker, spring—that they would never, ever find again. The first lamp loss had reduced their primary light source by a third. She had just cut it by another third. Down here, except for air, light was their most precious live-preserving resource. This was a crisis that threatened both their lives.