A big hydraulic cylinder flew out of the air and banged end over end to their left, and they both jumped. He hadn’t seen it coming.
After that, stillness. They stood nearly a minute, and then Boone stirred. He was sweating; they were in pressurized suits, but at 49 degrees Centigrade the shaft bottom was the hottest place on Mars, and the suit’s insulation was built for cold. He made a move to help Okakura to his feet, but stopped himself; presumably the man would rather get up himself than owe giri to Boone for the help. If Boone understood the concept properly. “Let’s have a look,” he said instead.
Okakura got up, and they walked back over the dense black basalt. The shaft had long ago bored into solid bedrock, in fact it was now about 20 percent of the way through the lithosphere. It was stifling at the bottom, as if the suits were entirely uninsulated. Boone’s air supply was a welcome coolness in the face and lungs. Framed by the dark shaft walls, the pink sky above was very bright. Sunlight illuminated a short conic section of the shaft wall. In midsummer the sun might shine all the way— no, they were south of the Tropic of Capricorn. In shadow forever, down here.
They approached the wreck. It had been a robot dump truck, hauling rock up the road that cut a spiral into the shaft wall. Pieces of the truck were mixed with big rough boulders, some scattered as much as a hundred meters from the point of impact. Beyond a hundred meters debris was rare; the cylinder that had flown by them must have been fired out under pressure of some kind.
A pile of magnesium, aluminum and steel, all twisted horribly. The magnesium and aluminum had partially melted. “Do you think it fell all the way from the top?” Boone asked.
Okakura didn’t respond. Boone glanced at him; the man was studiously avoiding his gaze. Perhaps he was frightened. Boone said, “There must have been a good thirty seconds between the time I caught sight of it and when it hit.”
At roughly three meters per second squared, that had been more than enough time for it to reach terminal velocity. So it had hit at about 200 kilometers per hour. Not so bad, really. On Earth it would have come down in less than half the time, and might have caught them. Hell, if he hadn’t looked up when he had, this one might have caught them. He made a quick calculation. It had probably been about halfway up the shaft when he saw it. But at that point it could have been falling for quite some time.
Boone slowly walked around into the gap between the shaft wall and the pile of scrap. The truck had landed on its right side, and the left side was deformed but recognizable. Okakura climbed several steps up the wreckage, then pointed at a black area behind the left front tire. John followed him up, scraped at the metal with the claw on his right glove’s forefinger. The black came away like soot. Ammonium nitrate explosion. The body of the truck was bent in there as if hammered. “A good-sized charge,” John observed.
“Yes,” Okakura said, and cleared his throat. He was frightened, that was sure. Well, the first man on Mars had almost been killed while in his care; and himself too, of course, but who knew which would scare him more? “Enough to push truck off road.”
“Well, like I said, there’s been some sabotage reported.”
Okakura was frowning through his faceplate. “But who? And why?”
“I don’t know. Anyone in your team seem to be having any psychological difficulties?”
“No.” Okakura’s face was carefully blank. Every group larger than five had someone experiencing difficulties, and Okakura’s little industrial town had a population of 500.
“This is the sixth case I’ve seen,” John said. “Although none so close up.” He laughed. The image of the birdlike dot in the pink sky came back to him. “It would have been easy for someone to attach a bomb to a truck before it came down. Detonate it with a clock or an altimeter.”
“Reds, you mean.” Okakura was looking relieved. “We have heard of them. But it is . . .” He shrugged. “Crazy.”
“Yes.” John climbed gingerly off the wreck. They walked back across the floor of the shaft to the car they had come down in. Okakura was on another band, talking to people up top.
John stopped by the central pit to have a final look around. The sheer size of the shaft was hard to grasp; the muted light and vertical lines reminded him of a cathedral, but all the cathedrals ever built would have sat like dollhouses at the bottom of this great hole. The surreal scale made him blink, and he decided he had tilted his head back too long.
They drove up the road inscribed in the side wall to the first elevator, left the car and got in the cage. Up they went. Seven times they had to get out and walk across the wall road to the bottom of the next elevator. The ambient light grew to something more like ordinary daylight. Across the shaft he could see where the wall was scored by the double spiral of the two roads: thread-marks in an enormous screw hole. The shaft’s bottom had disappeared into the murk, he couldn’t even make out the truck.