The Waters Rising by Sheri S. Tepper

for things were changing, Bear had said, and they had to make plans.
    Upstairs, in the little corner room that always caught the morning sun, she introduced him without preamble. “This is my friend Abasio.” Having mentally tried to explain him to herself, she had decided not to try to explain him to anyone else.
    The two Tingawans looked him over without expression. Abasio merely stood, perfectly relaxed, neither fidgety nor presumptuous, awaiting their verdict.
    “Where from?” asked Bear eventually.
    “Some years ago I was east of here, past the first range of mountains, past the desert that lies east of them, over the second range of mountains, the Great Stonies, and down onto the plains beyond. There were cities there then.”
    “And now? What happened to them?”
    “Gone, mostly, struck by a plague. The restorers have been busy since. They’re still planting trees where the cities were. They’ve brought back animals and birds. The plague killed most of the warlike people; the ones who are left are peaceable. The Edges are still there. Those are places around the old cities where the Old Sciences are still understood.”
    “Dangerous?” murmured Bear.
    Abasio shook his head. “I think not. The people in the Edges have a noninterference doctrine. They know what they know; they pass it on to their children; they preserve their knowledge, but they don’t bother anyone else with it. They have one unbreakable rule: they must understand everything a discovery is capable of before they use it in any way. If it can hurt, they don’t use it.”
    “There’s been a lot of talk about the waters rising.”
    Abasio shrugged. “The Edgers told me the waters will keep coming. They said that when the earth was formed, the aggregation included several huge ice comets. They were mixed and surrounded by a lot of stone, so there were reservoirs of water deep inside the planet that nobody knew were there. Recently, they’ve found a way out. There’s a country called Artemisia, south of the mountains. The Big River used to run through there and the land went on south a long way before it came to a part of the ocean they called the Gulf. Now over half that land is gone. Of course, it was lowland to begin with. I haven’t been to the East End of this continent, but I’ve heard about it. All the cities that used to be along the eastern shore are underwater now, or with their tops sticking out. There’s people living in the tops of the old buildings. They go back and forth in boats. Down below, in the parts below water, they farm oysters and mussels.”
    Bear snorted. “We hear about other places. I’m not sure I believe it.”
    Abasio regarded him thoughtfully. The people in the courtyard had told him that Bear disbelieved most things he hadn’t seen for himself—except that the winning card was destined for his hand. Bear was said to be a dreadful and losing wagerer. “You don’t need to go far to learn the truth of it, just to Ragnibar Fjord, between Wold and Kamfels. I’ve seen old maps, really old maps. You know there’s an ocean west of the Icefang Mountains where there used to be farmland stretching westward for hundreds of miles?”
    “We do know that,” said Precious Wind, quelling Bear’s snort before it sounded.
    “An earthquake went right down that whole side of the continent, split a piece of it off, and the ocean came in. What’s now Ragnibar Fjord used to be a river canyon flowing to the west, into the sea. The river made a dogleg north for a way, then went west to the ocean. The ocean flooded up that river canyon, kept coming south, around the bend, then it’s turned east for a few miles.”
    “Where Krakenholm is,” said Bear.
    “No. Past where Krakenholm was, ” said Abasio. “I was there a few days ago. Now the buildings at Krakenholm are underwater. Somebody’s built new ones on the higher rock, but they don’t look permanent to me.”
    “How far?” asked Precious Wind, her eyes