The water of the lake was always liquid, while the water ice coating the underside of the dome had to stay frozen. This explained most of their mesocosmic weather, as Sax put it, giving them their mists and sudden winds, their rain and fog and occasional snow. On this day the weather machine was almost silent, the big hemisphere of space under the dome nearly windless. With the wave machine turned off, the lake soon settled down to a round flat plate. The surface of the water became the same white color as the dome, but the lake bottom, covered by green algae, was still visible through the white sheen. So the lake was simultaneously pure white and dark green. On the far shore the dunes and scrub pines were reflected upside down in this two-toned water, as perfectly as in any mirror. Nirgal stared at the sight, entranced, everything falling away, nothing there but this pulsing green/white vision. He saw: there were two worlds, not one— two worlds in the same space, both visible, separate and different but collapsed together, so that they were visible as two only at certain angles. Push at vision’s envelope, push like one pushed against the envelope of cold: push! Such colors!...

“Mars to Nirgal, Mars to Nirgal!”

They laughed at him. He was always doing that, they told him. Going off. His friends were fond of him, he saw that in their faces. Coyote broke chips of flat ice from the strand, then skipped them across the lake. All of them did the same, until the intersecting white-green ripples made the upside-down world shiver and dance. “Look at that!” Coyote shouted. Between throws he chanted, in his bouncing English that was like a perpetual song: “You kids are living the best lives in history, most people just fluid in the great world machine, and here you’re in on the birth of a world! Unbelievable! But it’s pure luck you know, no credit to you, not until you do something with it, you could have been born in a mansion, a jail, a shantytown in Port of Spain, but here you are in Zygote, the secret heart of Mars! ‘Course just now you’re down here like moles in a hole, with vultures above all ready to eat you, but the day is coming when you walk this planet free of every bond. You remember what I’m telling you, it’s prophecy my children! And meanwhile look how fine it is, this little ice paradise.”

He threw a chip straight at the dome, and they all chanted Ice Paradise! Ice Paradise! Ice Paradise! until they were helpless with laughter.