P. Deutermann - The Last Man

He sat there on the edge for a moment. What are you waiting for? he asked himself. The image of that wet-suited figure hovering above him looked back at him from the black surface. Was he really ready to go back underwater? He’d been mentally skating around a grimmer possibility regarding the incident in the harbor. Had someone tried to warn him off what he was doing? If so, that someone had to know what he was up to, and if that was true, the someone might decide to take even harsher measures now that he’d come back to the mountain. He shook his head like a wet dog to clear away the dark thoughts and then dropped into the water.

He adjusted his mask and regulator and let go of the pipe. He was now neutrally buoyant, not floating anymore but definitely not sinking. He arced over and began to swim down into the cistern. The water was not exactly clear, but it wasn’t murky either. He turned periodically to sight in on the reference line with its dangling light, which was more visible now that he was heading down into the cavern. Of the walls he could see absolutely nothing, and he experienced a moment of vertigo as he stopped, suspended in a volume of water, his headlamp sending refracted beams of light into the void. He was absolutely, positively breaking all the rules here: a deep dive, by himself, no backup on the surface, and into a cavern about which he knew nothing. Brave? Yes, but not very bright, as he had heard his Uncle Jack say all too often.

After three minutes, he finally reached the bottom and hovered upright, paddling upward with gentle flapping motions to stay near the bottom. Then he bent over to touch the bottom and found, to his amazement, that it was littered with what looked like crusty, earthen half-sized bricks. There was a film of superfine silt along the bottom, and his efforts to inspect the bricks immediately enveloped him in a brown cloud. He swam sideways away from the silt cloud until the water cleared. He looked around for the reference light and found it behind him, not where he expected it to be. He looked straight up to assure himself that his bubbles were going up, not sideways or even down. They were. His wrist depth gauge indicated one hundred and four feet. He looked at his dive console compass and then started swimming due west, which should take him to the interior wall of the cavern. After a minute and a half he came up against it, a smooth rock surface that appeared to be natural, not man-hewn like the cisterns in the fortress’s side walls.

Suspicions confirmed, he thought; much too big to have been man-made. He turned right, or north, and swam along the wall, ascending now to eighty feet, looking for steps or a ladder of some sort cut into the wall, but there was nothing. He did notice that there was a thin, boiling cloud of silt trailing behind him.

He kept an eye on the glow of his reference light out in the middle and realized that after a minute or so, it was moving to his right, which meant the cavern was indeed spherical, with a continuously curving wall. When he got to what should be the north side, he checked his time and found he had about eight minutes left, based on a hundred-and-ten-foot dive. He kept checking his compass, and when he was swimming in a southerly direction he ascended to seventy feet, some thirty-five feet off the floor of the cavern. Here there were no more silt clouds. The bottom must be layered with very fine mud particles. He kept going until he was headed west again, which meant he had reached the southern curve of the sphere. Still no features worth mentioning, just smooth rock walls, with the occasional vein of quartz gleaming back at him.

He stopped when he was pointed north again, alongside the west wall, and checked time and depth. The timer was based on the deep dive of a hundred and ten feet, but he had been at eighty to seventy feet longer than he had been at the deepest depth. He had a few extra minutes. He was comfortable enough from the exertion of breathing and swimming, but he knew he dared not push it. One of the first deadly things nitrogen did was to cloud a diver’s judgment. He checked his reference light once more and was just barely able to see its glow out there in the middle somewhere. He realized he should have left another light on up at the exit hole, in case something happened to the reference light.

Crazy shit you’re doing down here, he thought. His old diving instructor would kick his ass three ways for this: long, hard, and often. Along with a lot of Israelis, too, he thought with a mental smile. He ascended again, now up to fifty feet, and reversed course, going back counterclockwise around the vast cavern, looking for anything at all. He’d made it all the way around the southern and eastern sides when his timer alarm pulsed. He reset it for two more minutes and kept going; if he was going to break all the safety rules, why not one more? Was that nitrogen talking?

He had traversed what should have been the western face when the timer pulsed again, and this time he turned his face up and began the ascent, straight up the wall.

Fifteen feet up a dark shadow caught his eye. He stopped and turned around.

There.

He swam over to the shadow and saw that a large round boulder was protruding out of the smooth rock wall like a bulging eyeball. It stuck out enough to create a shadow when his headlamp hit it from below. He swam around it, wondering why there would be this discontinuity in the otherwise smooth cistern wall. There was another shadow ten feet away. He swam over to this and discovered a narrow opening. A cave? He put his head in and saw that the cave was very shallow, a pit more than a cave. It ended about eight feet back. He pulled out and saw yet another shadow. Same thing — another small fissure that went nowhere.

He went back to the boulder and checked his console. Thirty-five feet. Air to spare. Swimming in place beneath it, he ran his hand over the slippery rock surface. Bits of rock fell away, as if it were rotten. It looked like sandstone, and the water had corroded the edges. He saw a small cloud of silt squirt out around the bottom of the boulder. Silt? Why would there be silt up here on the side of the cistern? There shouldn’t be—

With a swelling wave of pressure, the boulder began to move, tipping out of the hole behind it and then coming straight down toward him. He backed furiously out of the way as the stone slid silently past him like a ship going down the building ways, grazing his chest and boots and rolling him in the water with its wake vortex. Then he was moving again, but this time, he was being sucked into a cave opening that had been behind the boulder. His tank and then his arms banged on the rock walls as he went in, rolling out of control, for a distance of about twelve feet before the cave narrowed to the point where the inrushing water pinned him to the walls. Finally everything settled down, and he could extract himself.

He paddled backward toward the entrance for a few feet while adjusting his diving rig and checking for problems. Everything seemed to be okay except his wildly beating heart. Then he focused on where his headlamp was pointing. The passage ahead was extremely narrow, but it was definitely a natural cave. More important, ten feet into the upwardly sloping passage he could make out what looked like a vertical stone slab. The slab was white in his headlamp light, not like the dark rock walls of the cavern at all. Bingo, he thought, and then remembered to look at his timer. Overtime.

He backed out and continued the ascent until his head bumped gently against the top of the drowned cavern. He looked for the reference light but could only see a faint, diffused glow well beneath him. There was no single point of light, just the glow. Idiot for not leaving a light in the entrance, he thought, as he fought down an impulse of panic. Then he regained control. His virtual depth was about two feet, so he had some time here, and still plenty of air. He swam around the rim of the cistern ceiling until he was pointed east again. Then he turned hard right and swam due south, trying to keep the glow directly beneath him. The first time he missed the line entirely and came up against the south wall. He turned left, went three feet or so, and then moved back out toward the center of the cavern, mentally trying to clamp down on his growing fear. The problem was that he was too far up above the damned light. If he didn’t find the line this time he would have to dive again, and that could cause him some nitrogen problems later. He needed to get out of the water and start the surface interval phase. He looked at his timer, which displayed an accusing zero on its dial.