A shout, a shallow reading. The master swung the Moonbird into the breeze and told the Connollys to prepare the anchor. Within a matter of yards, we had come up from twenty-five fathoms to one. He waited for the wind to take us back off the edge of the pale rock that was now alarmingly plain to see below us. With deep green restored, he turned and found the doctor by the foot of the quarterdeck.

‘Myrmidon Rock, Doctor Gideon. A high peak in a flat sea floor. Some creatures, maybe?’

The doctor set about dropping his various nets and pots. When he had them all tied off on sturdy lines, he produced a fishing reel and began cutting bait on a board. Within half an hour he had filled a basket with fish: long slender ones, spiky brown flat ones. I recognised the schnapper from Port Jackson, the same fish that glowed upon the lid of the doctor’s curious cabinet.

When he was satisfied with the haul, he tipped it out on the deck and sorted through it, a child among toys, assigning each flapping and crawling creature a fate. Pin this one, fixative, sketch—no, the jars for that. Heterodontus, no, not you as he tossed a small shark overboard. I watched—I tried not to be seen watching—his capable hands gripping the fishes as he studied them. When he was done, the process of anchoring and sail orders was reversed, and we crept towards the domes of Hummock Island as though careful not to disturb it.

We were to land on the western side, in the lee of the easterly breeze, and part ways to survey the island. Now it had come to the practical business of the voyage, I found I had little idea how we would carry out our task, what we would do if we came upon the wreckage of the Howrah or the remains of the souls aboard. What if there were survivors? And what were we to do if we came upon the wreckers? We had proceeded upon assumptions, and now they were firing questions back at us.

And there was a further complication: my father was unwell. At noon he began to vomit. Draped under the cathead, grasping it feebly to steady himself, he brought up a thick white substance streaked with blood. I watched the tips of his fingers as he heaved and retched and saw they were shaking uncontrollably.

I urged him to remain aboard and recover: in part out of concern for him, but also with an eye to the difficulty of managing him onshore. If he had been ill-equipped for vengeance before, now he was a clear liability.