'Get your artisan's pliance and your sword, and follow me, Crafter.'

'I have them,' said Irisis tersely. They did not like each other; moreover, Irisis's sharp tongue had once done Fyn-Mah a wrong and she did not know how to repair it.

'Now!' rapped the perquisitor. 'Scrutator's orders, Crafter.'

Irisis knew better than to question her. A perquisitor, the rank below scrutator, could give orders to the master of a city and expect them to be obeyed without question. Besides, Irisis knew why Flydd wanted her out of the way. Ghorr would not have forgotten her escape from Nennifer, and he still wanted to know how she'd killed Jal-Nish's mancer up on the aqueduct at the manufactory. It was a secret that threatened all mancers.

Fyn-Mah reappeared carrying a small pack and they slipped through the guards and over the edge of the hill into a shrubby gully which ran away from the battlefield. Flangers was standing in the shadows halfway down. He nodded to Fyn-Mah, then fell in beside Irisis.

'What's going on?' she said in a low voice. 'I'm to assist you to the limit of my ability,' he said, which was no help at all.

Fyn-Mah kept to the centre of the gully, where the cover was densest, and after ten minutes they reached the foot of the hill. One of the air-floaters was tethered only a stone's throw away. She headed for it.

'Act as if we own it; Fyn-Mah said over her shoulder. They emerged from the scrub directly behind the machine. Fyn-Mah stood up and rapped on the side. The vessel suspended from the airbag was about eight spans long and three wide, shaped like a round-ended boat, but flimsy, being made from stretched rope, canvas and light framing timbers. The deck was canvas, the sides just rope netting that served to stop people from falling overboard, while a central cabin about four spans by two provided shelter, sleeping space and a tiny separate galley. It was also made of canvas framed with timber, with a light timber door suspended on leather hinges.

The air-floater was a different design to the one Flydd had brought from the east. A ten-bladed rotor, shielded at the front by a wire grid, was mounted on a stanchion at the stern of the craft. The rotor could be swung on a steering arm, making the big machine quite manoeuvrable. The controller was fixed to the steering arm. Above the rotor, mounted on a bracket, sat a complex mechanism in a metal housing, with a small water barrel on top. A pipe ran from the mechanism up to the airbag, and another out to the rear. It appeared to be a device to create floater gas, which, Irisis thought, was a considerable improvement on having to fly all the way to a suitable mine to replenish it.

A soldier, lounging against the rail, let out a squawk. He leapt for his spear, let it fall when he saw the perquisitor's badge, and snapped to attention.

Fyn-Mah climbed through the rope mesh and nodded to the captain of the guard. Irisis and Flangers followed. There were ten soldiers on board, counting the captain of the guard.

'We're going to take a look inside the wall of Snizort,' Fyn-Mah said. 'What's your name, Pilot?'

The pilot was a young woman with hair the bright yellow of a daffodil, freckles all over her thin face, and a charming gap between her front teeth. She was small and slender; all pilots were, for the weight mattered.

'Inouye, surr' The pilot bowed her head, unwilling to look the perquisitor in the face, but cast a pleading glance sideways at the captain of the guard. A young man with sunburnt cheeks and a thin, pointed nose, he would not look at Fyn-Mah either but inflated his cheeks and frowned. He did not want to deny a perquisitor, but he answered to another master. 'We're ordered to wait here,' he said, studying the canvas floor.

'By whom?'

'Acting Scrutator Jal-Nish Hlar. This is his air-floater.'

'My orders come from Scrutator Xervish Flydd, the com-mander-in-chief of all the forces here.' Fyn-Mah showed him a parchment which contained the scrutator's seal.

The captain gulped, nodded and gave the word to the pilot. Inouye slipped an open helm of crystals and wires over her head, took hold of the controller and screwed up her face as she sought for a distant, usable field. The rotor began to spin. The soldiers cast off the tethers and the air-floater rose out of the grass.

'Stay low,' said Fyn-Mah, checking an instrument concealed in her hand. 'Head that way, keeping just above the enemy's catapult height.' She held out her arm, directing the pilot.

The air-floater rotored gently towards the northern wall of Snizort, crossing over a number of smaller tar seeps where the hard resource had been mined down in benched cones, then a valley that had once been full of the same material. Now only black patches remained, some still smoking, for the lyrinx had fired the tar runs at the beginning of the battle. They saw no sign of the enemy.

'You're taking a risk, aren't you?' Irisis said quietly to Fyn-Mah. They were standing up the front by themselves.

'The scrutator has given me a valid instruction,' the perquisitor said stiffly, then, thawing a little, 'Besides, I am incurably identified with Xervish Flydd. If he falls, so must I.'

'You could change allegiances,' Irisis said slyly, to see how Fyn-Mah would respond.

'Change once and you are forever tainted, your word worthless. I have sworn to my scrutator and will not break my oath, whatever it costs me.'

'There are many who would not be so noble.' She spoke without thinking.

'I'll watch my back.' Fyn-Mah said icily. Especially when you're behind me, was the implication.

Irisis had not meant her words the way they were taken, but it was too late to withdraw them.

The wall of Snizort was four spans high and equally thick, topped with thorn bushes scarred here and there by fire, and torn and smashed by catapult balls. The wall had been breached in five places and was unmanned.

They cruised along inside. The breaches, and the smashed gate, were piled with the bodies of the dead, lyrinx and human. Other dead were scattered across the enclosed space. Irisis saw no sign of live enemy, though from a high point she could see columns of lyrinx streaming away to the south-west in the direction of the Sea of Thurkad. Their withdrawal had been astonishingly swift.

Smoke issued from a tarry bog and several of the pits, which would make access to the underground city difficult. The ground above the node-drainer, which had risen up in a red-hot dome just before the node exploded, was now a fractured, fuming hole. Further off, though still inside the walls, the Great Seep formed a bottomless cauldron of tar about a league across. The source of the tar at Snizort, it was steaming gently. The exploded node lay some leagues to the north, and underground, but it was too smoky to see that far.

The sun touched the western horizon. Irisis looked the other way, back towards the command hill. The scrutators must be inside the tent, with Flydd. She turned towards Snizort again. 'There can't be any creature left alive underground,' she muttered. 'The whole place is on fire.'

'That's where you're wrong.' Fyn-Mah replied. "Tar burns hot, but it burns slowly. Most of the city will yet be untouched. Let's go.'

'In there? We'll choke before we've gone a dozen spans.'

'The fire draws air to it. Away from the burning core, the air should be fresh. Our orders are to get inside, if we can, and recover any of the flesh-formed creatures left alive.'

'We may get in,' said Irisis, 'though I doubt we'll ever get out again.' She said it fatalistically. Having expected to die for so long now, in so many hideous ways, she was no longer moved by the thought of danger. She indicated the largest pit. 'That's where the scrutator and I entered last time. Though .., we had the seeker to find the way for us.'