Chapter One

The Hunting Ground

It was a dark, blustery afternoon in spring, and the city of London was chasing a small mining town across the dried-out bed of the old North Sea.

In happier times, London would never have bothered with such feeble prey. The great Traction City had once spent its days hunting far bigger towns than this, ranging north as far as the edge of the Ice Wastes and south to the shores of the Mediterranean. But lately prey of any kind had started to grow scarce, and some of the larger cities had begun to look hungrily at London. For ten years now it had been hiding from them, skulking in a damp, mountainous western district that the Guild of Historians said had once been the island of Britain. For ten years it had eaten nothing but tiny farming towns and static settlements in those wet hills. Now, at last, the Lord Mayor had decided that the time was right to take his city back over the land bridge into the Great Hunting Ground.

It was barely halfway across when the lookouts on the high watchtowers spied the mining town, gnawing at the salt flats twenty miles ahead. To the people of London it seemed like a sign from the gods, and even the Lord Mayor (who didn't believe in gods or signs) thought it was a good beginning to the journey east, and issued the order to give chase.

The mining town saw the danger and turned tail, but already the huge caterpillar tracks under London were starting to roll faster and faster. Soon the city was lumbering in hot pursuit, a moving mountain of metal that rose in seven tiers like the layers of a wedding cake, the lower levels wreathed in engine smoke, the villas of the rich gleaming white on the higher decks, and above it all the cross on top of St. Paul's Cathedral glinting gold, two thousand feet above the ruined earth.

Tom was cleaning the exhibits in the London Museum's Natural History section when it started. He felt the telltale tremor in the metal floor, and looked up to find the model whales and dolphins that hung from the gallery roof swinging on their cables with soft creaking sounds.

He wasn't alarmed. He had lived in London for all of his fifteen years, and he was used to its movements. He knew that the city was changing course and putting on speed. A prickle of excitement ran through him, the ancient thrill of the hunt that all Londoners shared. There must be prey in sight! Dropping his brushes and dusters, he pressed his hand to the wall, sensing the vibrations that came rippling up from the huge engine rooms down in the Gut. Yes, there it was—the deep throb of the auxiliary motors cutting in, boom, boom, boom, like a big drum beating inside his bones.

The door at the far end of the gallery slammed open and Chudleigh Pomeroy came storming in, his toupee askew and his round face red with indignation. "What in the name of Quirke . . . ?" he blustered, gawking at the gyrating whales, and the stuffed birds jigging and twitching in their cases as if they were shaking off their long captivity and getting ready to take wing again. "Apprentice Natsworthy! What's going on here?"