He had sensed someone was following him, but seen nothing whenever he looked back. Now he knows why: his doppelgänger is a lad, moving about like a drop of quicksilver that cannot be trapped under the thumb. Ten years old, Enoch guesses. Then the boy thinks about smiling and his lips part. His gums support a rubble of adult teeth shouldering their way into pink gaps, and deciduous ones flapping like tavern signs on skin hinges. He's closer to eight. But cod and corn have made him big for his age – at least by London standards. And he is precocious in every respect save social graces.