She hurried to make her appointment in the shadow of the Ribs, the Bonetown Claws, in the Thieves’ Quarter. Behind her, for a moment, the sky was very full: an aerostat droned in the distance; tiny specks lurched erratically around it, winged figures playing in its wake like dolphins round a whale; and in front of them all another train, heading into the city this time, heading for the centre of New Crobuzon, the knot of architectural tissue where the fibres of the city congealed, where the skyrails of the militia radiated out from the Spike like a web and the five great trainlines of the city met, converging on the great variegated fortress of dark brick and scrubbed concrete and wood and steel and stone, the edifice that yawned hugely at the city’s vulgar heart, Perdido Street Station.

CHAPTER THREE

Opposite Isaac on the train sat a small child and her father, a shabby gent in a bowler hat and second-hand jacket. Isaac made a monster face at her whenever she caught his eye.

Her father was whispering to her, entertaining her with prestidigitation. He gave her a pebble to hold, then spat on it quickly. It became a frog. The girl squealed with delight at the slimy thing and glanced shyly up at Isaac. He opened his eyes and mouth wide, mumming astonishment as he left his seat. She was still watching him as he opened the door of the train and stepped out onto Sly Station. He made his way down and onto the streets, wound through the traffic for Brock Marsh.

There were few cabs or animals in the narrow twisting streets of the Scientific Quarter, the oldest part of the ancient city. There were pedestrians of all races, as well as bakeries and laundries and guildhalls, all the sundry services any community needed. There were pubs and shops and even a militia tower; a small, stubby one at the apex of Brock Marsh where the Canker and the Tar converged. The posters plastered on the crumbling walls advertised the same dancehalls, warned of the same coming doom, demanded allegiance to the same political parties as elsewhere in the city. But for all that apparent normality, there was a tension to the area, a fraught expectancy.

Badgers—familiars by tradition, believed to have a certain immunity to the more dangerous harmonics of hidden sciences—scampered past with lists in their teeth, their pear-shaped bodies disappearing into special flaps in shop doorways. Above the thick glass storefronts were attic rooms. Old warehouses on the waterfront had been converted. Forgotten cellars lurked in temples to minor deities. In these and all the other architectural crevices, the Brock Marsh dwellers pursued their trades: physicists; chimerists; biophilosophers and teratologists; chymists; necrochymists; mathematicians; karcists and metallurgists and vodyanoi shaman; and those, like Isaac, whose research did not fit neatly into any of the innumerable categories of theory.

Strange vapours wafted over the roofs. The converging rivers on either side ran sluggishly, and the water steamed here and there as its currents mixed nameless chymicals into potent compounds. The slop from failed experiments, from factories and laboratories and alchymists’ dens, mixed randomly into bastard elixirs. In Brock Marsh, the water had unpredictable qualities. Young mudlarks searching the river quag for scrap had been known to step into some discoloured patch of mud and start speaking long-dead languages, or find locusts in their hair, or fade slowly to translucency and disappear.