The beat accelerated even more. The vast machine was at full throttle. The oars moved in great circles at a mad tempo. The slaves pumped with all their might. Horrified but unable to look away, I studied their grinning faces – jaws clenched, eyes burning with fear and confusion.

There was a loud snap and a crack, as if one of the great oars had suddenly split asunder, so close that I covered my face. In the same instant the boy who had smiled at me threw back his head. His mouth wrenched open in a silent howl.

The whipmaster raised his arm again. The lash slithered through the air. The boy shrieked as if he had been scalded. I saw the lash slither across his naked shoulders. He faltered against the oar, tripping on the catwalk. For a long moment he hung suspended from the manacles around his wrists as he was dragged forwards, backwards and up again. As he hung from the highest point, desperately trying to find his balance, the whip lashed against his thighs.

The boy screamed, convulsed and fell again. The oar carried him for another revolution. He somehow found his grip andj oined in the effort, every muscle straining. The lash struck again. The drumbeat boomed. The whip rose and fell. Squealing and gasping from the pain, the boy danced like a spastic. His broad shoulders convulsed at the whipmaster's rhythm, out of time with the great machine. His face contorted in agony. He cried like a child. The whipmaster struck him again and again.

I looked at the man's face. He smiled grimly back at me, showing a mouth full of rotten teeth, then turned and spat across the shoulders of one of the straining slaves. He looked me in the eye and he raised his whip again, as if daring me to interfere.

With a single voice the rowers groaned, like a tragic chorus. I looked at the boy, who never ceased rowing. He looked back at me and moved his lips, unable to speak.