I found myself trying to recollect the face of Marcus Crassus, the richest man in Rome. I had seen him a hundred times in the Forum, but his visage escaped me. I counted money in my head, imagining the soft jingle of coins in a purse, and spent my fee a dozen times over. I thought of Bethesda; I imagined her sleeping alone with the kitten curled up between her breasts, and I traced a path by memory from room to room through my house in Rome, like an invisible phantom standing guard. Abruptly an image rose unbidden in my mind, of Belbo lying across my portal in a drunken stupor, with the door wide open for any thief or assassin to step inside…

I gave a start and sat upright. Eco turned in his sleep and made a chattering noise. I strapped on my shoes, wrapped the blanket around me like a cloak, and returned to the deck.

Here and there sailors lay huddled together in sleep. A few strolled the deck, watchful and alert for any danger from the sea or shore. A steady breeze blew from the north, filling the sail and raising gooseflesh wherever the blanket did not cover my arms and legs. I strolled once about the deck, then found myself drawn towards the portal amidships that led down into the galley.

It is curious that a man can sail upon many ships in his life and never wonder at the hidden motive power that drives them, yet this is how most people live their lives every day – men eat and dress and go about their business, and never give a thought to all the sweat of all the slaves who laboured to grind the grain and spin the cloth and pave the roads, wondering about these things no more than they wonder about the blood that heats their bodies or the mucus that cradles their brains.

I stepped through the portal and down the steps. Instantly a wave of heat struck my face, warm and stifling like rising steam. I heard the dull, throbbing boom of the drum and the shuffling of many men. I smelled them before I saw them. All the odours that the human body can produce were concentrated in that airless space, rising up like the breath of demons from a sulphurous pit. I took another step downward into a world of living corpses, dunking that the Jaws of Hades could hardly lead to a more terrible netherworld than this.