Sel bent over and squat-walked into the tunnel. But it was hard to keep going that way—his back was too old. He couldn't even lean on his stick, because it was too tall for the space, and he had to drag it along, keeping it as close to vertical as possible so the oil didn't spill out of the canister at the top.
After a while he simply could not continue in that position. Sel sat down and so did Po.
"This is not working," said Sel.
"My back hurts," said Po.
"A little dynamite would be useful."
"As if you'd ever use it," said Po.
"I didn't say it would be morally defensible," said Sel. "Just convenient." Sel handed his stick, with the lamp atop it, to Po. "You're young. You'll recover from this. I've got to try a new position."
Sel tried to crawl but instantly gave up on that—it hurt his knees too much to rest them directly on the rocky floor. He finally settled for sitting, leaning his arms forward, putting weight on them, and then scrabbling his legs and hips after him. It was slow going.
Po also tried crawling and soon gave up on it. But because he was holding the stick with the light, he was forced to return to walking bent over, knees in a squat.
"I'm going to end up a cripple," said Po.
"At least I won't have to hear your mother and father complain about what I did to you, since I don't expect to get out of here alive."
And then, suddenly, the light went dim. For a moment Sel thought it had gone out, but no—Po had stood up and lifted the stick to a vertical position, so that the tunnel where Sel was creeping along was now in shadow.
It didn't matter. Sel could see the chamber ahead. It was a natural cavern, with stalactites and stalagmites forming columns that supported the ceiling.
But they weren't the straight-up-and-down columns that normally formed when lime-laden water dripped straight down, leaving sediment behind. These columns twisted crazily. Writhed, really.
"Not natural deposits," said Po.
"No. These were made. But the twisting doesn't seem designed, either."
"Fractal randomness?" asked Po.
"I don't think so," said Sel. "Random, yes, but genuinely so, not fractal. Not mathematical."
"Like dog turds," said Po.
Sel stood looking at the columns. They did indeed have the kind of curling pattern that a long dog turd got as it was laid down from above. Solid yet flexible. Extrusions from above, only still connected to the ceiling.
Sel looked up, then took the stick from Po and raised it.
The chamber seemed to go on forever, supported by the writhing stone pillars. Arches like an ancient temple, but half melted.
"It's composite rock," said Po.
Sel looked down at the boy and saw him with a self-lighting microscope, examining the rock of a column.
"Seems like the same mineral composition as the floor," said Po. "But grainy. As if it had been ground up and then glued back together."
"But not glued," said Sel. "Bonded? Cement?"
"I think it's been glued," said Po. "I think it's organic."
Po took the stick back and held the flame of the lamp under an elbow of one of the twistiest columns. The substance did not catch fire, but it did begin to sweat and drip.
"Stop," said Sel. "Let's not bring the thing down on us!"
Now that they could walk upright, they moved forward into the cavern. It was Po who thought of marking their path by cutting off bits of his blanket and dropping them. He looked back from time to time to make sure they were following a straight line. Sel looked back, too, and saw how impossible it would be to find the entrance they had come through, if the path were not marked.
"So tell me how this was made," said Sel. "No toolmarks on the ceiling or floor. These columns, made from ground-up stone with added glue. A kind of paste, yet strong enough to support the roof of a chamber this size. Yet no grinding equipment left behind, no buckets to carry the glue."
"Giant rock-eating worms," said Po.
"That's what I was thinking, too," said Sel.
Po laughed. "I was joking."
"I wasn't," said Sel.
"How could worms eat rock?"
"Very sharp teeth that regrow quickly. Grinding their way through. The fine gravel bonds with some kind of gluey mucus and they extrude these columns, then bind them to the ceiling."
"But how could such a creature evolve?" said Po. "There's no nutrition in the rock. And it would take enormous energy to do all this. Not to mention whatever their teeth were made of."
"Maybe they didn't evolve," said Sel. "Look—what's that?"
There was something shiny ahead. Reflecting the lamplight.
As they got closer, they saw reflections from spots on the columns, too. Even the ceiling.
But nothing else was as bright as the thing lying on the floor.
"A glue bucket?" asked Po.
"No," said Sel. "It's a giant bug. Beetle. Ant. Something like—look at this, Po."
They were close enough now to see that it was six-legged, though the middle pair of limbs seemed more designed for clinging than walking or grasping. The front ones were for grasping and tearing. The hind ones, for digging and running.
"What do you think? Bipedal?" asked Sel.
