‘I didn’t realise there had been snow,’ I said, before I could think, before I could stop myself.

Pitzmun’s silence was as damning an admonishment as any I’d had since my childhood. But that was how it looked: like snow. It coated the jagged rise and fall of the pocked earth. It frosted the branches of pine for a good fifty yards in either direction. There was no breeze to stir it, to dislodge it, or move it on from this place; and a caustic, harsh smell dominated even that of the pine.

I glanced at Pitzmun. I saw, in the tightness at the corners of her lips and the dazed look to her eyes, that the young woman was struggling against the horror of what lay outside the fort. A constant, coldly picturesque reminder of what they’d had to do.

‘The fires burned for days,’ she said, in barely a whisper. ‘You wouldn’t think it took so long, but it does.’

She told me how the dragoons had dug pits, lined them with wood, and laid their comrades to rest. From Pitzmun’s description I had no doubt the process was managed with the utmost respect and compassion for their fellows-in-arms. But they had not expected the ash.

‘I’ve seen pyres,’ Pitzmun said, shaking her head. ‘Just as many bodies, if not more, burned. Never seen anything like this.’

I’d thought the airlessness of the forest to blame for the covering. But a gust of wind rose then, strong enough to sway the treetops and their branches below, but not the ash. I knelt and rubbed some of it between my fingers. It wasn’t particularly sticky and crumbled at my touch as any ash would.

‘The colonel won’t come down here, not since the flames went out,’ Pitzmun said.

I stood and stared at the strange scene before me. So still, so pristine despite its awful origin; I felt as if I stood at the foot of an enormous painting. A winter painting, as cold and callous and unrepentant as the season itself.

‘What is to be done about it?’ I said.

‘Done?’ Pitzmun said. ‘Nothing. Even if the colonel could give the order to clear it, even if he thought such a thing possible, none of the troopers would do it. Would you?’

‘No, I suppose not.’

‘Whatever— Whoever’s responsible, it’s an evil thing to do.’

I agreed. ‘The sword shrivels to flakes of snow.’

‘What’s that, sir?’

‘Something I read, before I journeyed south.’

I recalled Ignatius, the library, and the Ritual of Berith with its conditions: the unfaithful lose sight of themselves. The sword shrivels to flakes of snow. The law devours its history. The stone moves on water. The broken heart bleeds gold.

There could be no longer be any doubt: the witch I sought was enacting the Ritual of Berith, one condition at a time, and in as ghastly a manner as was available to the imagination. First Jan Harsson’s eyes, then Constable Webber’s inexplicable demise, and now the unnatural ash.