He led Avatak back up the beach to the cave, outside which Pyxeas sat, cradling an empty soup bowl, and Avatak was impressed that he had managed to finish a meal for once. Pyxeas had Muka help him up, and with the others followed Crimm into the dimly lit rear of the cave.

But Pyxeas paused by the fire where there was a heap of paper, evidently used as kindling. He ruffled through this, appalled. ‘By the mothers’ mercy – did this come from the Archive? I know this work – on the philosophy of the motion of the planets – centuries old! And it’s been used to light a fire for a bunch of—’

‘Not now, master,’ Avatak murmured firmly.

Pyxeas fell silent, visibly angry.

They walked deeper into the cave. At the back a little girl, not more than five years old, lay on a heap of skins. A woman, perhaps her mother, stood back as they approached, hope and fear obvious in her face. Avatak became aware that they were all watching him, all the Northlanders, and he felt a stab of self-doubt.

‘Just do your best,’ murmured Pyxeas, leaning on Muka.

Tentatively Avatak bent over the little girl. Listless, lethargic, she did not resist. He saw she had spots on her skin, on her face and arms and, he saw when he lifted a blanket, on her legs. She had evidently been suffering from nosebleeds, and when he gently opened her mouth he saw teeth missing from bleeding gums.

‘She’s been so down,’ said the mother. ‘So miserable for so long.’

‘Many of us have the same symptoms,’ Crimm said. ‘To one degree or another.’

‘And you know what she asks for, all the time? Cabbage! Who would have thought it? But you can’t grow cabbage in all this snow and ice.’

Pyxeas grunted. ‘I bet that’s the answer. You people seem to have plenty of fish and meat to eat, but not a scrap of green.’

Avatak felt faintly irritated, for Pyxeas was right. ‘We call it the bleeding fever. Yes, it comes about if you don’t eat all you need.’

‘I need cabbage,’ whispered the little girl, and her mother stroked her head.

Pyxeas said, ‘So what’s the answer, boy? Should we boil up some seaweed?’

‘No. Not that. We call it mattak. You can chop it into small pieces and eat it raw, or you can fry it and boil it to make it easier for the children. That will stop this sickness.’

Crimm frowned. ‘Mattak? What is that?’

‘The skin of a whale.’

There was a long silence.

Crimm said, ‘And to get hold of that . . .’

‘First you have to catch a whale.’ Avatak grinned. ‘It’s not hard. I will show you.’