Gulls overhead, him failing beside me. The romantic vision of the wide world had fallen away now: there was nothing out here to discover, nothing to exhilarate. This was not the way I had thought our urgent mission would play out. And what if my father died out here? I looked at my feet: could I bury him in this rocky ground, no tools, no god, no congregation to hear the words? It would be just like him to expire somewhere so inconvenient.

‘I’m looking around us, Father,’ I said when he stumbled to a halt. ‘There is nothing out here. The doctor is up there, up to our left.’ His face followed the change in the direction of my voice. ‘The master’s along that beach to the right, to the south.’ Again, he sensed the orientation. ‘This is a waste of time, I believe. Why don’t we go back?’

He bent over and clutched his knees, teeth gritted. One hand left his knee and rose to shoulder height, extended, and the fingers dabbed softly at the air. His face was tensed with listening, as the fingers explained something to him.

‘Up there,’ he said, with considerable effort. ‘On the ridge line. Is there limestone coming out of the ground?’

‘Yes. How did you know that?’

‘Wind’s coming from that way. Smells different with the air on it. Limestone makes overhangs, is where anybody’d shelter. We need to…huargh!…go and look.’ He had vomited again. At least I would not be called upon to clean it off this particular surface.

But the word he’d used. Look. I thought, for the first time, that he was using it to mean inquire. But who was ‘anybody’?

We pressed on, uphill now towards the reef of limestone he had somehow sensed. He fell more often as the ground inclined, catching his feet in the thick bases of the tussocks. He would tumble forward, cursing, then spike his hands on the needle-tip blades and curse some more, clutching his profanities between teeth gritted against the nausea.

We reached the limestone in the middle of the day. Both the doctor and the master had been able to complete their circuits in the time it took us merely to get up there. They were waiting at the entrance to a large cave. Argyle sat in silent contemplation, looking out over the blue expanse of the sea stretching eastwards, back towards Great Island. His soft cotton dress was damp with sweat where it gathered over his chest, and thousands of tiny grass seeds decorated the skirts as though the dressmaker had intended them to be there. He picked at them idly.