There were many objections to that, and the discussion grew heated.

Pyxeas was growing agitated. ‘You’re not thinking it through. Any of you. You’re not thinking it through.’ But for now, in a swirl of argument, nobody was listening.

The Coldlander boy was with him, silent and stolid. Pyxeas rested his hand on the boy’s arm. The stranger seemed to sympathise with the scholar, over dilemmas he could surely barely understand, and the little scene surprised and touched Alxa. Alxa suddenly felt very sorry for this ancient great-uncle, tortured by the knowledge that was evidently eating away inside him, knowledge he seemed so poor at sharing. She got up and went to him.

Pyxeas looked at her warily, squinting. ‘The light is so poor in here. You’re not Rina, are you?’

‘No. I am Alxa. Rina’s daughter.’ She took his arm and made him sit down, and knelt beside him, holding his hand. ‘Just tell me, Uncle. What is it that we don’t understand?’

He looked at her with a kind of bleak gratitude. ‘That this isn’t some anomaly. Some variation from the norm. These recent seasons of cold and rain and drought. The astronomical calculations prove it . . . This is the future. It will get colder and colder. This is inevitable. Maybe you can buy off some of the farmers this season. But next summer, when they come again – what then?’

Still nobody else was listening.

Ywa clapped her hands to call for order. ‘Pyxeas, your contribution has been – umm, invaluable. Crimm, perhaps we can discuss the question of the fish stocks before we must face our guests again, and decide on the bounty we can afford . . .’

They began to file out of the room.

Pyxeas, abandoned, collected together the scrolls and slates littering the floor with the Coldlander boy.

But Alxa stayed beside him. ‘Uncle,’ she said cautiously. ‘Are you saying you understand? You understand why, how, the world is cooling down?’

‘Yes. No! Not quite,’ Pyxeas admitted miserably. ‘There was a divergence.’

‘A divergence?’

‘According to the historical record there was a warming, when the world should have been cooling. Lasted up to about two millennia ago. An anomaly. I don’t know what caused it – don’t know why it ended – I don’t have the numbers to match the anecdotal evidence. Still less do I understand what caused it. And until I know all that, I can’t see the future with any definitiveness. And that’s why I needed to speak to the scholars of Cathay.’

Much of this went over Alxa’s head. ‘But you quoted the lines about the ice giants. You’re not saying the ice giants were real? And that – what? That they’ll come again?’

He looked at her, as if seeing her clearly for the first time with his rheumy eyes. ‘No, child. The ice giants weren’t real. People can only describe the things they see in terms they understand. But the ice – that was real.’