A little way to the north-east rose Vaudois Hill, a sinuous wedge of high land which rose up as if trying to block the view to the centre of the city. The Spike, Perdido Street Station, Parliament, the Glasshouse dome: all were visible, butting their way over that raised horizon. Opposite the hill, Lin saw miles and miles of Rudewood disappear over uneven ground. Here and there little rock knolls broke free of the leaf-cover. Off to the north there was a long uninterrupted line of sight over to the middle-class suburbs of Serpolet and Gallmarch, the militia tower of St. Jabber’s Mound, the raised tracks of the Verso Line cutting through Creekside and Chimer. Lin knew that just beyond those soot-stained arches two miles away was the twisting course of the Tar, bearing barges and their cargo into the city from the steppes of the south.

Isaac lowered his hands as his pupils tightened.

Whirling over their heads aerobatically were hundreds of garuda. They began to drop, to spiral neatly out of the sky and drop to their clawed feet in rows around Lin and Isaac. They fell thickly from the air like overripe apples.

There were two hundred at least, Lin estimated. She moved a little closer to Isaac nervously. The garuda averaged at least a couple of inches over six feet, not counting the magnificent peaks of their folded wings. There was no difference in height or musculature between men and women. The females wore thin shifts, the males wore loincloths or cut-off trousers. That was all.

Lin stood five feet tall. She could see no further than the first circle of garuda who surrounded her and Isaac at arms’ length, but she could see more and more dropping from the sky; she had the sense of the numbers building up around her. Isaac patted her shoulder absently.

A few shapes still swept and hunted and played in the air around them. When the garuda had stopped landing on the roof, Isaac broke the silence.

“Righto,” he yelled. “Thanks very much for inviting us up here. I want to make a proposition to you.”

“To who?” came a voice from the crowd.

“Well, to all of you,” he replied. “See, I’m doing some work on . . . well, on flight. And you are the only creatures in New Crobuzon who can fly and have brains in your bonces. Wyrmen aren’t renowned for their conversational skills,” he said jovially. There was no reaction to his joke. He cleared his throat and continued.

“So, anyway . . . uh . . . I’m wondering whether any of you would be willing to come and do a couple of days’ work with me, show me some flight, let me take a few prints of your wings . . .” He took hold of Lin’s hand that contained the camera and waved it around. “Obviously I’ll pay for your time . . . I’d really appreciate some help . . .”