PASSING THROUGH the Great Gate, he borrowed a lantern from a porter and exited onto a walkway that led to the street, hemmed in by crenellated walls. The wall to his left had a narrow gate let into it. Using his old key, Daniel opened the lock on this gate and stepped through into a sizable garden. It was laid out as a grid of gravel walkways with squares of greenery between. Some of the squares were planted with small fruit trees, others with shrubs or grass. To his left a line of taller trees screened the windows of the row of chambers that filled the space between the Great Gate and the Chapel. The buds in their branches were just evolving to nascent leaves, and where light shone from Isaac's windows they glowed like stopped explosions, phosphorus-green. But most of the windows were dark, and the stars above the muzzles of the chimneys were sharp and crystalline, not blurred by heat or dimmed by smoke. Isaac's furnaces were cold, the stuff in their crucibles congealed. Their heat had all gone into his skull.