Mummius's men looked and acted like legionnaires out of uniform. Beneath their light woollen cloaks I caught the glint of knives, which made me feel safer at the prospect of venturing through Roman streets after dark. I reached inside my cloak and touched my own dagger. Mummius had said that all my needs would be supplied, but I preferred to bring my own weapon.

Mummius had not counted on Eco, so I was given the strongest mount and he rode behind me, clutching my waist. Where my body is broad and thick through the shoulders and chest (and in recent years, through the middle as well), Eco's is thin and wiry; his added weight was hardly enough for the beast to notice.

The evening was mild, with only a faint early-autumn chill in the air, but the streets were nearly deserted. In times of trouble, Romans shun the darkness and lock up their houses at sundown, leaving the streets to pimps, drunks, and thrill seekers. So it was in the turmoil of the civil wars and the gloomy years of Sulla's dictatorship; so it was again now that the revolt of the Spartacans was on everyone's lips. Terrifying stories were told in the Forum about whole villages where citizens had been overwhelmed and roasted alive by slaves who ate their former masters for dinner. After sundown Romans refused party invitations and vacated the streets. They locked their bedchamber doors to keep out even their most trusted slaves while they slept, and they woke up from nightmares, drenched in sweat. Chaos was loose in the world again, and his name was Spartacus.

We clattered through the Subura past alleys that stank of urine and rotting garbage. Our way was lit here and there by the glow from open windows along the overhanging upper storey; snatches of music and drunken laughter wafted over our heads and faded behind us. Above us, the stars looked very far away and very cold, a sign of a frosty winter to come. It would be warmer down in Baiae, I thought, where summer lingers in Vesuvius's shadow.