The day was warm and a dry breeze blew out of the west. A good day for making cash.

Cars found a pebble. His hands were full. He picked it up in his toes and put it in his pocket. After he let Tools off at the mirror garden, he hid behind a solar array and examined his find. It tasted siliceous, with a hint of manganese. It was smooth and cool, pleasing to touch, so he kept it, despite its condition of no value.

Tools knew Cars had found something while carrying her to the garden. After making sure that her latest crop of mirrors had sufficient nutrients and were growing well, she called Tracks.

"Honey, I have a job of mutual profit." Tracks was already shaking her head.

"Cash up front. Always cash up front. You know that."

Tools bit the side of her finger while she thought. "Two mirrors. You choose."

They settled on three, and Tracks was on the case. What did Cars find, and what was it worth?

Cars and Digs were sitting together on the bluff. The horizon was rising to meet the sun. Digs spat the pebble out and handed it back.

"It doesn't taste good and it's not nutritious. It is only a pebble."

"I have wondered," he replied, "does everything have to have measurable value?"

She pushed him down and straddled him. "Compare," she said.

He popped the pebble in his mouth.

Cars dropped Digs off at the landfill excavation and ran to the taxi stand.

"You're late!" Bossman shouted, his hair standing up in fury. "You're docked a day's pay." He leaned forward and sneered. "We gotta be faaaaiiiiir!"

"You know what? I don't think that IS fair. Also, I don't want to carry people all day. Let them walk." He dropped the pebble into Bossman's hand.

"So what is it?" Tools asked. Tracks shrugged.

"He gave it to Bossman. Bossman threw it in the dirt and I picked it up. But it's only a pebble."

"Did he do anything special while he had it?"

"No. Put the pebble in his mouth and had sex with Digs."

Tools looked at the pebble. She tasted it. "You got the wrong thing. Go look again."

"Keep your mirrors," said Tracks, "I've got work to do." She put the pebble in her pocket, running her thumb over it as she walked away.

The end