Thux rested his face on the fur of his hood, with the cold growstone beneath. He seemed to be falling asleep, his thoughts receding into the warmth of his own skull. It was almost comforting to lie here, in the care of his mother as she worked at his damaged hand. He couldn’t even feel the cold any more.

But there was something missing.

He forced his head up. ‘Mother. Can you hear that?’

‘What?’

‘The engine.’

She lay there for a moment, silent and still as the wind howled around them.

The pumping heartbeat of the engine had stopped, and the growstone beneath them was as inert as a corpse.

17

It was Mago who spotted the first cracked pane in the roof.

By now it was the dead of night. Nelo had been working flat out, like everybody else, since he’d first come here to the Hall of Annids, and he had no precise idea of the time. Doctor Ontin had got his emergency hospital running pretty quickly. Mago and Nelo had been used as spare muscle in Ontin’s scheme to sort out the continuing trickle of injured and ill as they kept arriving through the night. Ontin himself, with other surgeons and nurses, was working hard on the more serious injuries, the broken limbs and crushing wounds, the frostbite, the cases of exhaustion, even a couple of heart attacks.

Things had got steadily worse. The heating had been off for hours, and the running hot water. Then even the cold water supply had failed, then the gas supply that fed the lanterns. Ontin, bossy, exasperated, had coped with all this as it had unfolded, barking out commands to anybody who would listen, including Ywa Annid of Annids, who made sure that what he wanted got done. Soon the Hall was studded with candles, and open fires blazed in antique hearths unused for a century. Clogged chimneys trapped smoke and the ash, and there wasn’t much to burn save smashed-up furniture – it was very expensive firewood – but the fires gave out enough heat to keep them all from freezing altogether.

But all through the night Nelo and Mago, remembering their adventure with the awning, had kept an eye on that roof, a great glass lid over them all, that had been covered with snow thick enough to block out the daylight even before the sun had set. In the dark it was easy to forget about, you couldn’t even see it in the flickering light of the candles. Nelo had tried a couple of times to warn Ywa about the problem, but she hadn’t really listened, and he understood; you couldn’t deal with everything at once. But the two of them had kept watching, and listening.

It was Mago who heard the first pane crack, even over the noise of the hospital, the cries of the injured, the squalls of babies, the general susurrus of conversation. He grabbed Nelo’s arm, almost making the Northlander drop the bundle of blankets he’d been carrying. ‘Look,’ he snapped in Greek. ‘Up there . . . near the centre . . .’