The militia’s dark suits were interwoven with fibres from man-o’-war hide. The tendrils could not penetrate them.

Ranks of militia charged the open spaces where the pickets were congregated. Men and vodyanoi wielded placards like badly designed clubs. Within the disorderly mass were brutal skirmishes, as militia agents swung spiked truncheons and whips coated with man-o’-war stings. Twenty feet from the front line of the confused and angry demonstrators, the first wave of uniformed militia dropped to their knees and raised their mirrored shields. From behind them came the gibbering of a shunn, then quick arcs of billowing smoke as their fellows hurled gas grenades over into the demonstration. The militia moved inexorably into the clouds, breathing through their filter-masks.

A splinter group of officers peeled off from the main wedge formation and bore down on the river. They threw tube after hissing tube of billowing gas into the vodyanoi’s watercraeft ditch. The croaks and screeches of burning lungs and skin filled the hole. The carefully maintained walls began to split and dribble as more and more strikers hurled themselves through into the river to escape the vicious fumes.

Three militiamen knelt at the very edge of the river. They were surrounded by a thicket of their colleagues, a protective skin. Quickly, the three at the centre pulled target-rifles from their backs. Each man had two, loaded and primed with powder, one of which they set beside them. Moving very fast, they sighted along the shafts into the miasma of grey smoke. An officer in the peculiar silver epaulettes of a captain-thaumaturge stood behind them, muttering quickly and inaudibly, his voice muffled. He touched each marksman’s temples, then jerked his hands away.

Behind their masks, the men’s eyes watered and cleared, suddenly seeing registers of light and radiation that rendered the smoke virtually invisible.

Each man knew the bodyshape and movement patterns of his target perfectly. The sharpshooters tracked quickly through the fog of gas and saw their targets conferring with wet rags clamped to their mouths and noses. There was a rapid crackle, three shots in a quick tempo.

Two of the vodyanoi fell. The third looked round in panic, seeing nothing but the swirl of that vicious gas. He raced to the water walling him in, scooped a handful from it and began to croon to it, moving his hand in fast and esoteric passes. One of the riverside marksmen dropped his rifle quickly and picked up his second weapon. The target was a shaman, he realized, and if given time he might invoke an undine. That would make things vastly more complicated. The officer raised the gun to his shoulder, aimed and fired in one brisk movement. The hammer with its clamped shard of flint slid down the serrated edge of the pan cover and snapped, sparking, into the pan.

The bullet burst through the gusts of gas, sending it coiling in intricate wreaths, and buried itself in the neck of the target. The third member of the vodyanoi strike committee fell squirming into the mire, the water dissipating in arcing spray. His blood pooled and thickened in the quag.

The watercraeft walls of the trench in the river were splintering and collapsing. They sagged and bowed, water breaching them in gouts and diluting the riverbed, eddying around the feet of the few remaining strikers, coiling like the gas above it, until with a shiver the Gross Tar reknit itself, healing the little rift that had paralysed it and confused its currents. Polluted water buried the blood, the political papers and the bodies.

As the militia put down the Kelltree strike, cables burst from the fifth airship as from its kin.

The crowds in Dog Fenn were shouting, yelling news and descriptions of the fight. Escapees from the pickets stumbled through the ramshackle alleys. Gangs of youths ran back and forth in energetic confusion.

The costermongers on Silverback Street were yelling and pointing at the fat dirigible uncoiling its dangling rigging to the earth. Their shouts were effaced in the sudden boom and drone of klaxons in the sky as one by one the five airships sounded. A militia squad abseiled through the hot air into the streets of Dog Fenn.

They slipped below the silhouetted rooftops into the rank air, then down, their huge boots hammering down the slippery concrete of the courtyard in which they landed. They looked more construct than human, bulked up by bizarre and twisted armour. The few workers and dossers in the cul-de-sac watched them with mouths gaping until one of the militia turned briefly and raised a huge blunderbuss rifle, sweeping it in a threatening arc. At that, the watchers dived to the ground or turned and fled.

The militia troops stormed down a dripping staircase into the underground slaughterhouse. They smashed through the unlocked door and fired into the swirling, bloody air. The butchers and slaughterers turned dumbfounded to the doorway. One dropped, gargling in agony as a bullet burst his lung. His gory tunic was drenched again, this time from the inside. The other workers fled, slipping on gristle as they ran.

The militia tore down the swinging, dripping carcasses of goat and pigmeat and yanked at the suspended conveyor-belt of hooks until it ripped from the damp ceiling. They charged in waves towards the back of the dark chamber and stomped up the stairs and along the little landing. For all that it slowed them, the locked door to Benjamin Flex’s bedroom might have been gauze.

Once inside the troops moved to either side of the wardrobe, leaving one man to unstrap a huge sledgehammer from his back. He swung it at the old wood, dissolving the wardrobe in three huge strokes, uncovering a hole in the wall that emitted the chugging of a steam engine and fitful oil-lamp light.

Two of the officers disappeared into the secret room. There was a muffled shout and the sound of repeated hammering thuds. Benjamin Flex came flying through the crumbling hole, his body twisting, beads of blood hitting his grimy walls in radial patterns. He hit the floor head first and shrieked, tried to scrabble away, swearing incoherently. Another officer reached down and lifted him by the shirt with steam-enhanced strength, shoving him against a wall.

Ben gibbered and tried to spit, staring at the impassive blue-masked face, intricate smoked goggles and gasmask and spiked helmet like the face of some insectile daemon.

The voice that emerged from the hissing mouthparts was monotonous, but quite clear.

“Benjamin Flex, please give your verbal or written assent to accompany myself and other officers of the New Crobuzon militia to a place of our choosing for the purposes of interview and intelligence gathering.” The militiaman slammed Ben against the wall, hard, eliciting an explosive burst of breath and an unintelligible bark. “Assent so noticed in presence of myself and two witnesses,” the officer responded. “Aye?”

Two of the militiamen behind the officer nodded in unison and responded: “Aye.”

The officer cuffed Ben with a punishing backhand blow that dazed him and burst his lip. His eyes wavered drunkenly and he dribbled blood. The hugely armoured man swung Ben up over his shoulder and stomped from the room.

The constables who had entered the little print-room waited for the rest of the squad to follow the officer back out into the corridor. Then, in perfect time, they each pulled a large iron canister from their belts and pushed the plungers that set in motion a violent chymical reaction. They threw the cylinders into the cramped room where the construct still cranked the printing press handle in an endless, mindless circuit.

The militiamen ran like ponderous bipedal rhinos down the corridor after their officer. The acid and powder in the pipebombs mixed and fizzed, flared violently, ignited the tightly packed gunpowder. There were two sudden detonations that sent the damp walls of the building shuddering.