For three years the glacier had been growing before the caves and the plateau’s southern face had been buried under snow for ten years. Only a few woods goats ever came as far north as the country south of the caves and they stayed only during the brief period between the last snow of spring and the first snow of fall. Their winter home was somewhere down near the equator. What had been called the Southern Lowlands was a frozen, lifeless waste.

Once they had thought about going to the valley in the chasm where the mockers would be hibernating in their warm caves. But even if they could have gone up the plateau and performed the incredible feat of crossing the glacier-covered, blizzard-ripped Craigs, they would have found no food in the mockers’ valley⁠—only a little corn the mockers had stored away, which would soon have been exhausted.

There was no place for them to live but in the caves or as nomads migrating with the animals. And if they migrated to the equator each year they would have to leave behind them all the books and tools and everything that might someday have given them a civilized way of life and might someday have shown them how to escape from their prison.

He looked again to the south where the halo should be, thinking: They should have made their decision in there by now. I’m their leader⁠—but I can’t force them to stay here against their will. I could only ask them to consider what it would mean if we left here.

Snow creaked underfoot as he moved restlessly. He saw something lying under the blanket of frost and went to it. It was an arrow that someone had dropped. He picked it up, carefully, because the intense cold had made the shaft as brittle as glass. It would regain its normal strength when taken into the caves⁠—