"Exactly," said Toroca. "The blue material the ship’s hull is made of is very, very dense — no doubt part of the reason it’s so incredibly strong. If you were to drop the ship into water, it would sink faster than a lead weight. Even with all the hollow spaces within, it’s still much too heavy to be a sailing ship."

"A ship for what medium, then?" asked Dybo.

"For space," said Toroca.

"What is ’space’?" asked Keenir.

"In this context," said Toroca, "the intervening volume between celestial objects."

"You mean the air?" asked the sailor.

"Perhaps."

"But if the ship is too heavy to float," said Dybo, "surely it’s too heavy to fly through the air."

"Novato’s flying machine, the Tak-Saleed, was heavier than air, and it flew."

Dybo nodded. "A ship of the air. A ship of — of space."

"That is what I believe, yes."

"And this ship’s purpose?" asked Afsan.

"To bring life here from wherever life really originated." said Toroca. He saw jaws drop around the circle and inner eyelids flutter in astonishment.

"What do you mean?" said Dybo.

Toroca gestured expansively, taking in the entire cliff face. "Those layers of rock are like the pages of a book," he said. "But they’re not a complete book. Most of the early pages are blank. It’s as though we’ve come in in the middle of the story. This rock book is — call it volume two in a series. Volume one is somewhere else, and that book, if only we could see it and read its pages, would show us our true origins."

"We did not originate here?" said Keenir.

"Does that shock you, old friend?" said Toroca.

Keenir shook his head. "I was with Afsan when he changed the world. I’m old, and if that has one advantage, it’s perspective: I’ve seen so much change during my lifetime. No, Toroca, it does not shock me."

"Evolution accounts for all the diversity of life," said Toroca. "Of that I’m sure. You see that lowest of the white layers in the rocks near the top of the cliff? The one we’ve called the Bookmark layer? That name is more apt than we knew: it marks the beginning of our story here, on this world, but by no means the real beginning of the saga of the Quintaglios. That book, as I’ve said, is elsewhere. We used to think the Bookmark marked the point of creation, but it does nothing of the kind. It merely marks the point of arrival. Life originated elsewhere, evolved elsewhere."

They all looked up at the cliff face, awe on their faces.

At last, Toroca pointed at the great blue ark. "And that, and doubtless others like it that did not fail, is how we got here." He shrugged. "Who knows? Maybe it was indeed one of eight ships." He glanced at Babnol. "Maybe, in that metaphorical sense, the story of the eggs of creation is correct."

He looked at them each in turn. "But, in any event, a huge time ago by our own standards, although quite recently in terms of the overall age of this world, our ancestors were — were — deposited here, transplanted by those astonishing beings who built this ship."

Dybo leaned back on his tail. "A ship of space," he said again. Everyone was quiet for a time, until Dybo spoke once more. "This gives the exodus new meaning." The Emperor tipped his head up, up, past layer after layer of rock, past the vast blue ark, past the Bookmark layer, past it all, all the way to the sky, far overhead. "We’re not just going to the stars," he said, his voice full of wonder. And then he tipped his muzzle down and nodded at his friends. "We’re going home."