The doctor fed a fishing line out off the stern as the Moonbird picked up speed. He had attached bright objects next to the hooks every ten feet or so: a spoon, a shaving razor, beads and even the shards of a glass my father had broken days before. Declan Connolly, watching the line, made a hand signal to the doctor every time he saw a big silver fish strike at one of the lures. The line was drawn in, the fish slashed through its throat and bucketed, and the process repeated.

We sailed west along the back of Long Island, aiming to round its western end and continue down the coast of the much larger island beyond, the one the master was calling Cape Barren. But before we could bring the coast of that island into view, there was a deafening blast. My first assumption was that my father had caused something to explode; but the master and Connolly were looking to the east.

As the boulders receded, we saw masts, a Union Jack, a high bow. Voices carried over the water to us from the direction of the ship.

‘Government cutter,’ said Argyle. ‘Now what would they be about?’

A clearing pall of smoke explained the bang: they had fired a cannon at the shore. Our course took us closer: now there was laughter, cheering. Another deafening percussion, smoke and the crashing of trees on shore. Men had climbed the rigging with rifles and were firing intermittently; crews bent over the three cannons on deck. I could see the powder boys rushing up from below, bearing small casks. Swabbers mopped out the barrel of one gun while other men rammed the barrel of another. A breath of flame appeared before the detonation reached us along with more cheering in the smoke, and I could see now that they were aiming at a large boulder that stood on the beach.

We were still sailing towards the cutter, but either they hadn’t noticed us, coming as we did from behind the corner of Long Island, or they didn’t care. They emptied more rounds into the boulder, shearing great shards of rock off its face but more often bringing down shrubs behind it or causing eruptions in the shallows in front. The gun captain moved from one cannon to another, inspecting the packing before he pulled the lanyard on the gunlock. With each successful firing he would slap the backs of the crew, horse-faced and braying, and they would set to work again.