Eight days alone, ten eleven thirteen: she loses track. The door doesn’t open. No one bangs on the other side of the walls. No one enters the Library. The only incoming water line into Vault One is a single, slow-dripping tube that she alternately plugs into the food printer or the recycling toilet. It takes several minutes to fill her drinking cup; she is perpetually thirsty. Some hours she presses her hands against the walls and feels trapped like an embryo inside a seed coat, dormant, waiting to wake up. Other hours she dreams of the Argos settling onto a river delta on Beta Oph2, the walls opening, everyone walking out into clear, clean rain, falling in sheets from the alien sky, rain that tastes faintly of flowers. A breeze strikes their faces; flocks of strange birds rise and wheel; Father smears mud on his cheeks and looks at her with glee, while Mother stares up, mouth wide, drinking from the sky—to wake from a dream like that is the worst kind of loneliness.

DayLight NoLight DayLight NoLight: inside the Atlas she walks deserts, expressways, farm roads, Prague, Cairo, Muscat, Tokyo, searching for something she cannot name. A man in Kenya with a gun slung over his back stands holding a razor as the cameras pass. In Bangkok she finds an open shopfront where a girl hunches behind a desk; on the wall behind her hang at least one thousand clocks, clocks with cat faces, clocks with panda bears for numbers, wooden clocks with brass hands, all their pendulums stilled. Always the trees draw her, a rubber fig in India, mossy yews in England, an oak in Alberta, yet not one image in the Atlas—not even the ancient Bosnian pine in the mountains of Thessaly—possesses the meticulous, staggering complexity of a single lettuce leaf in Father’s farm, or of her pine sapling in its little planter, its textures and surprises; the rich, living green of its long needles, tipped with yellow; the purple-blue of its cones; xylem trundling minerals and water up from the roots, phloem carrying sugars away from the needles to be stored, but just slowly enough that the eye cannot see it happen.

Finally she sits exhausted on the cot and shivers and the diodes in the ceiling dim. Mrs. Chen said Sybil was a book that contained the entire world: a thousand variations of recipes for macaroni and cheese, the record of four thousand years of temperatures of the Arctic Sea, Confucian literature and Beethoven’s symphonies and the genomes of the trilobites—the heritage of all humanity, the citadel, the ark, the womb, everything we can imagine and everything we might ever need. Mrs. Flowers said it would be enough.

Every few hours the questions rise to her lips: Sybil, am I the only one left? Do you pilot a flying graveyard with one soul left on board? But she cannot bring herself to ask.