By the year 48 B.C., when this novel takes place, the flawed Roman calendar had drawn some two months ahead of the actual seasons. Thus, although the story begins on the 27th of September by the Roman calendar, the season is actually high summer, and the date, by modern reckoning, is closer to the 23rd of July.

"There! Can you see it? The lighthouse!"

Bethesda gripped my arm and pointed to a sparkle of light on the dark horizon. It was the hour before dawn. The deck of the ship rocked gently beneath our feet. I squinted and followed her gaze.

All night Bethesda had stayed awake, awaiting the first glimpse of the great lighthouse of Alexandria. "It could be any minute now," the captain had told us the previous day at twilight, and Bethesda had staked a place at the prow of the ship, her gaze set on the southern horizon, where blue-green sea met azure sky. Slowly the blues darkened to deepest purple and then to black; the sky was pierced with stars, and starlight lit the face of the deep; a sliver of moon traversed the sky, and still the lighthouse did not appear. It seemed we were not quite as close to Alexandria as the captain thought, yet I trusted his navigation; the voyage from Rome had so far been quick and uneventful, and even I could tell from looking at the stars that our course was now due south. The steady breeze at our backs was taking us across a calm sea directly toward Egypt.

All night I stood beside Bethesda, joining in her vigil. The night was warm, but occasionally she shivered, and I held her close. Many years ago we had departed from Alexandria by ship, watching the flame atop the lighthouse for hours as it gradually dwindled and finally vanished from sight. Now we were returning to Alexandria, and again we stood together on a ship, scanning the horizon for a first glimpse of that same undying flame.