After she had gone I sat and tried to conquer my feelings. I could sense that she had tried to unnerve me and I had observed her greedy enjoyment of my discomfort. Or had I misread her and she had told me only to warn me? And I was cold to my bones.

The silence was too heavy. I knew that even if that were not the truth, that there was some truth in what she had said. The idea that while I slept, William stood in Hettie’s room above to stare out at the island was too dreadful to digest. I must not allow myself to think of it.

But if there were ghosts they were passive, surely, beyond will and thought, only leaving their imprint upon the earth? They could not touch or harm, and yet that was not true either because did not Mary talk to William?

I thought of Ailsa and her knowledge of the pebbles and the widows’ whistle. If ghosts existed perhaps these things too had a power I had never before acknowledged. I remembered the pipe in the attics, recalling its shape and for what it was hewn. Surely not, I told myself, but before I knew it, I was hurrying out of the house and up the valley, reaching Ailsa’s out of breath.

The croft stood in near darkness; only the thinnest twist of smoke spiralled on the grey clouds. I knocked but it took a while for her to answer, and one look at her flushed skin and bloodshot eyes made me ashamed of my visit. She too was ill and I turned to leave, but she took my cuff and pulled me in.

For once she sat with her hands idle.

‘You are unwell. I should go.’

‘You are here now and I can see that what you want to say is important.’

The kitchen smelt sour and I regretted my decision. ‘You have told me of the widows’ whistle, of the pebbles and what they were made for. Do you believe that such objects can achieve their purpose?’

She grimaced. ‘Why do you ask?’

‘You know why I ask. You know.’ In spite of myself my eyes pricked and I wiped angrily at them with the back of my hand. ‘All is not well at Iskar,’ I said. ‘You know this. It is full of things that … things that do not make sense in the world I understand.’

She coughed into a cloth and when she had finished a sweat stood out on her brow, but I could not continue: it was as if in uttering my fears aloud they would become more true.