Gargle checked his instruments. “Thin ice bearing east-by-north-east-a-half-east, about six miles,” he squeaked.
Tom still had little idea of the size or shape of the Screw Worm, but watchers on the upper tier saw it clear in the moonlight now as it shot out from beneath the city, narrowly avoiding the drive-wheel. It was a house-high metal spider, its fat hull supported by eight hydraulic legs, each ending in a broad, clawed disc of a foot. Black smoke spurted from exhaust-ports on its flanks as it ran eastward, back along the track made by Anchorage’s runners.
“A parasite!” growled Scabious, dashing out on to a maintenance platform above the drive-wheel to watch it go. Anger bubbled up inside him, forcing apart the locks and bolts with which he had fastened down his feelings since his son died. Some filthy parasite clinging to his city like a tick! Some thieving parasite-boy tricking him into believing that his Axel had returned!
“We’ll stop them!” he shouted to his people. “We’ll teach them to steal from Anchorage! Tell the Wheelhouse ready about! Umiak, Kinvig, Kneaves, with me!”
Anchorage dug in its starboard ice-rudders and came about. For a while nobody aboard could see anything for the glittering curtains of snow the runners had flung into the air. Then the parasite appeared again, a mile ahead, veering north-east. The city put on speed to give chase, while Scabious’s people heaved the jaws open and gnashed them to clear the ice that had formed on the banks of steel teeth. Searchlights fumbled across the snow, stretching the parasite’s crooked running shadow ahead of it. Closer, closer, until the jaws were snapping so near to the thing’s stern that a puff of smoke from its exhausts was trapped inside. “Once more!” bellowed Scabious, standing on the floor of his city’s small gut. “This time he’s ours!”
But Windolene Pye peered at her charts and saw that the city was speeding towards a place the survey teams had marked with red crosses: a place where open water had skimmed over with ice that would not bear a city’s weight. She swung the engine district telegraph to ALL STOP and Anchorage backed its engines, dug in all its anchors and came shivering to a halt with a shock that scattered black flocks of tiles from the rooftops and brought down an empty terrace of rust-sick buildings on the upper tier.
The parasite machine ran on, stilting its way out on to the treacherous ice. Scabious stared out through the open jaws and watched it slow and halt there. “Ha! We’ve driven him on to the thin stuff! He’ll dare go no further! He’s ours now!” He ran through the gut to the garage where the survey-teams kept their sleds, snatching a wolf-rifle from one of his men as he went. Someone dragged a sled out for him and fired the engines up, and he leapt aboard it and went rushing down the exit chute, a steel door sliding open ahead of him. Out on the ice he swung around the city’s jaws and sped towards the cornered spider-thing, a dozen of his men on other sleds whooping and shouting behind him.
Tom squinted through the limpet’s windows, trying to shield his eyes against the glare of Anchorage’s searchlights. He could already hear the faint shouts of his rescuers, the crack of wolf-rifles fired into the air, the throaty stutter of sled engines hammering towards him across the ice.
“If you just let me go, I’ll put in a good word for you,” he promised his captors. “Scabious isn’t a bad sort. He’ll treat you well if you just hand back the things you’ve stolen from his engine district. And I know Freya won’t want you punished.”
The little boy, Gargle, looked as if he might be convinced, glancing fearfully from Tom to the approaching sleds. But Skewer just said, “Quiet,” and Caul’s pale hands kept dancing across the consoles. The Screw Worm lurched into motion again, settling its fat body lower until the hull was resting on the ice. Whirling saw-blades slid out of its belly, and jets of heated water sprayed against the ice, sending up fierce clouds of steam. With clumsy movements of its legs the Screw Worm turned, turned, cutting an escape-hole for itself. When the circle was complete the blades folded back into the hull and the machine pushed itself down, shoving the plug of ice aside and forcing its body through into the water below.
A hundred yards away Scabious saw what was happening. Steering the sled with his knees he took his hands off the controls and raised his rifle, but the bullet banged off the armoured hull and went whining away across the ice like a lost bee. The parasite’s bulbous eyeball windows sank out of sight. Wavelets lapped across its back, sloshing over magnetic grapples and crab-camera ports. Its long legs folded themselves one by one into the hole, and it was gone.
Scabious brought his sled to a stop and hurled his rifle away. His prey had escaped him, taking Tom and the parasite-boys with it, and he could imagine neither where it was bound, nor any way that he could follow. Poor Tom, he thought, for in spite of his gruffness he had liked that young aviator. Poor Tom. And poor Axel, who was dead, dead, dead, his ghost not walking Anchorage’s byways after all. Nobody returns from the Sunless Country, Mr Scabious.
He was glad of his cold-mask. It stopped his men from seeing the tears that were coursing down his face as they parked their own sleds close to his and ran to peer into the hole the escaping parasite had cut.
Not that there was anything there to see. Only a broad circle of open water, and the waves slapping and clopping at its edges with a sound like sarcastic applause.
Freya had been woken by the lurching of the city, by the noise of bottles of shampoo and jars of bath-salts crashing down from the bathroom shelves where she had abandoned them. She rang and rang for Smew, but he did not come, and in the end she had to venture out of the Winter Palace alone, perhaps the first margravine to do such a thing since Dolly Rasmussen’s time.
At the Wheelhouse everybody was shouting about ghost-crabs and parasite-boys. Not until it was all over did Freya understand that Tom was gone.
She couldn’t let Windolene Pye and her staff see that she was crying. She hurried off the bridge and down the stairs. Mr Scabious was on his way up, dripping snow and meltwater as he tugged off his gauntlets and cold-mask. He looked flushed, and more alive than she had seen him since the plague, as if the discovery of the parasite had freed something in him. He almost smiled at her.
“An amazing machine, Your Radiance! Drilled straight through the ice-sheet. You have to hand it to the devils! I’ve heard legends of parasites on the High Ice, but I confess, I always thought them just old icewives’ tales. I wish I’d been more open-minded.”
“They took Tom,” said Freya in a small voice.
“Yes. I’m sorry. He was a brave lad. Tried to warn me of them, and they caught him and dragged him inside their machine.”
“What will they do with him?” she whispered.
The engine master looked at her, then shook his head, and pulled off his hat as a mark of respect. He wasn’t sure what the crew of a vampire-parasite-spider-ice-machine might want with the young aviator, but he couldn’t imagine it was anything nice.
“Can’t we do something?” Freya asked plaintively. “Can’t we dig, or drill, or something? What if this parasite thing resurfaces? We must wait here and watch…”
Scabious shook his head. “It’s long gone, Your Radiance. We can’t hang about here.”
Freya gasped as if he’d slapped her. She wasn’t used to having her orders questioned. She said, “But Tom’s our friend! I won’t just abandon him!”
“He is just one boy, Your Radiance. You have a whole city to think of. For all we know, Wolverinehampton is still on our trail. We must move on immediately.”
Freya shook her head, but she knew her engine master was right. She had not turned back for Hester when Tom had begged her to, and she could not turn back now for Tom, no matter how much she wanted to. But if only she had been nicer to him, these past weeks! If only her last words to him hadn’t been so snappish and cold!