I nodded dully. We walked past warehouses and jetties, through shut-down markets and shipyards. The smell of salt grew stronger on the air, and the vague hissing of the sea joined with the steady lapping of the river. We came to the end of the docks, where the Tiber abruptly broadens and empties into the sea. The city wall swung away to the south, and a vast, starlit prospect of calm waters opened before us. Here another, larger boat awaited us. Mummius ushered us down the steps and into the hold. He barked at the overseer and the boat cast off.

The dock receded. The waves began to swell around us. Eco looked alarmed and clutched my sleeve. 'Don't worry,' I told him. 'We won't be on this boat for long.'

A moment later, as we navigated around a shallow, rocky promontory, the vessel came in sight. 'A trireme!' I whispered.

'The Fury, she's called,' said Mummius, seeing my surprise and smiling proudly.

I had expected a large ship, but nothing as large as this one. Three masts, their sails cowled, rose from the deck. Three rows of oars projected from her belly. It hardly seemed possible that such a hulking monster had been dispatched merely to fetch a single man. Mummius lit a torch and waved it over his head. A torch was lit on deck and waved back at us. As we drew nearer, men suddenly swarmed about the deck and up the masts, as quiet as ghosts in the starlight. The oars, retracted from the water, stirred like the quivering legs of a centipede and dipped downward. Sails unfurled and snapped taut in the soft breeze. Mummius wet his finger and held it aloft. 'Not much of a wind, but steady to the south. Good!'

We drew abreast. A rope ladder was lowered. Eco scrambled up first and I followed. Marcus Mummius came last and pulled up the ladder behind him. The smaller boat drew away, back toward Ostia. Mummius walked quickly up and down the length of the ship, giving orders. The Fury heaved and swung about. The steady rhythm of oarsmen groaning in unison rose up through the boards, and on either side there was a great splash as the first stroke sliced into the waves. I looked back at Ostia, at the narrow beach that fronted the city's shoreward side and the tiled rooftops that rose above the walls. The town receded with stunning speed; the walls dwindled, the gulf of dark water grew greater and greater. Rome suddenly seemed very far away.