He then told the porter to stand by, opened the core access door with a key he kept around his neck, and disappeared inside. The door slammed shut and we heard his footsteps hurrying down the spiral staircase, clanging on the steel treads as he went.

‘You should both leave if you want to,’ said the porter, his hand hovering over a large pull-down handle that was marked ‘EMERGENCY CORE FLOOD’.

As a porter he had initially seemed ineffectual and flippant, but now it had come to crunch time, he would do as all porters do – never abandon their sleeping charges and go down with their Dormitorium, if required. I was learning that the Winter had a curious integrity all of its own.

‘We’ll hang around,’ said Logan, confident, I think, that between the porter and Tiffen the issue could be resolved. He didn’t ask me if I would stay, but then as his Novice, I was kind of part of him. After a few minutes we heard Oliver Tiffen’s voice over the crackly loudspeaker, and he explained the problem, which was kind of technical, but involved a loss of water in the safety tank or something, and that everything was ‘cooking up down here’. We then heard ‘oh shit’, a few more choice swear words and then, in a calm and measured tone: ‘flood flood flood’.

The porter didn’t hesitate for an instant, and pulled the lever. There was a rumbling from somewhere deep below that sounded like rushing wet cement, then silence. The temperature gauge dropped suddenly and all the other dials slowly fell to zero.

‘Well,’ said the porter, ‘that’s me out of a job.’

*   *   *

The Beryl Cook had two hundred residents, and everyone still awake lent a hand to move them out. The walking awake and the dozing were sent to emergency bedrooms in other Dormitoria, but anyone in the treacly abyss of the Hib was consigned to Honeycomb Sleepshacks still in their beds, as they wouldn’t know the difference until they woke up. The mayor herself actually turned up with a retinue of large and very yawny bureaucrats, who were all eager to downplay the accident, probably because it meant returning to bed quicker and less paperwork.

‘I think we should call this a Level Three “Serious Incident”,’ she said, ‘rather than a Level Four: “An Accident with Local Consequences”. Don’t you?’

‘Didn’t the accident kill Mr Tiffen?’ asked Logan, knowing the difference.

‘Technically-speaking he wasn’t killed by the reactor – he drowned. This is really more to do with the coastguard.’

‘It was under twenty tons of boron slurry,’ Logan pointed out.

‘Agreed,’ replied the mayor. ‘They’ll dig him out in the Spring. His sacrifice will be remembered, and he will be honoured.’