The leftway ended at a narrow bridge. He crossed it with the others, riding past the counterweights that fanned out from its hinges to allow the bridge to be lifted.

Around him the aquar were folding their legs, sinking the Masters and Marula to the ground. Carnelian saw more aquar were waiting for them, larger than the ones they had been riding, as sleek and silver as fish. Their plumes were the colour of poppies. Elegant saddle-chairs were strapped to their backs. Slaves held them with auxiliaries standing to one side. Carnelian wondered by what sorcery they had known of their coming.

A marumaga came forward and knelt before Aurum. Suth was still climbing out of his chair. Carnelian had accepted his father's assurance about his wound and was thus alarmed to see with what care he moved and, when he straightened, how he pressed a hand to his side. Other slaves ran forward to deal with the baggage. Tain was helped down. He looked round at Carnelian with a face so gaunt that Carnelian almost did not know him. His brother gave a thin smile that was very Tain, forcing Carnelian to remember Jaspar's offer. The thought of betraying his wounded father put a knot in Carnelian's stomach.

The Marula were already mounting the new aquar. Tain was rummaging through the baggage. He pulled some packs from it and then watched as the grooms began to carry the rest away.

A whining caused Carnelian to look down to see a groom offering him a fresh aquar. He examined the man's face around the bloodshot, fearful eyes. The forehead was branded with the sea glyph and four bars. By the way three of the bars were grouped, Carnelian read all four together, as 115. Craning, he looked up the tower to where its wooden ribs overhung the leftway like the branches of a tree. He found that the plaque attached to the middle rib bore the same number. Above this a man was hanging in a kind of cage.

The groom was still there below him, waiting. Carnelian gave his mount the signal that made it lower him to the ground. He climbed out of the saddle-chair and pointed up at the caged man. 'Punishment?'

The groom fell to his knees and bowed his head.

Carnelian nudged the man with his foot. 'Well?'

'A lookout, Master, in a deadman's chair.'

Carnelian left the man alone, and mounted the fresh aquar who pushed him smoothly up into the air. He ran his hand along the oily black curving rim of his new seat. Adjusting himself into it, he found that it fitted him better. As he moved towards the other Masters he was surprised by the different rhythm of the aquar's walk.

Vennel moved his animal to block his way. The speed is delightful, my Lord, is it not?'

Carnelian could not understand why Vennel was suddenly trying to make conversation.

'How frequently must we make these stops?' he heard his father say.

‘I will try to keep them to a minimum, my Lord,' said Aurum. 'But it will serve neither of us if we lose speed.'

The Master moved off to speak to the marumaga tower keeper. Carnelian made some polite noises and walked his aquar round Vennel’s to approach his father.

'Are you in pain, Lord?' he asked quietly when he had come near.

'It will get better,' his father replied. 'It is just that the riding has opened the wound a little. Where is Tain?'

Carnelian looked round and found his brother sitting in between the legs of one of the Marula.

'Are we ready, my Lords?' said Aurum.

The Masters made signs of affirmation. Aurum lifted his hand signing, Windspeed.

On and on like arrows flying. Three watch-towers they ignored but, as the aquar were tiring, they stopped at the fourth that was numbered 111 from which Carnelian surmised they would pass 110 more before reaching Osrakum. Again, exactly the right number of fresh aquar were waiting for them.

Carnelian felt a giddiness from stopping and the clammy hot clutch of the odoured air. His problems returned, his unease. He hungered for the cool rushing oblivion in the mouthing wind. Instead there was the humdrum rumble from the road below, anxiety over the pain his father concealed, the sight of Tain being passed among the Marula like a parcel. The changeover was faster this time and he breathed his relief when he was up again in the wind that washed everything away.

At watch-tower sea 109, they paused again. Everything had been ready, and they quickly resumed their headlong speed. They had passed one more tower and the next one was just a peg pinning the road's thread down to the plain when it emitted a spark. Ahead, an aquar flared its plumes as if it had been startled and began to fall back.

He saw its rider, Aurum, pulling on its reins, straining to look round. At first Carnelian thought that the Master was looking back at him but soon realized he was looking past him. Carnelian struggled to look round the back of his chair. The watch-tower they had just left was holding a star between its stretched-up hands. This disappeared, then reappeared. He watched it flash on and off several times, then nothing. He sat back, rubbing the twisting out of his neck. He froze when he saw the tower ahead giving an answering candle flicker.

The next time they stopped Carnelian tried to see what it was that was up there, on the platform held up by the watch-tower's six arms. There was nothing to see. As they set off he made sure to keep his eye on the road ahead. Two flashes near the rusty horizon confirmed his suspicion. The watch-tower ahead had been informed of their coming.

Two more watch-towers went by and a third was in sight when Carnelian saw it give a double flash. He was wondering what it could be responding to when they all began to slow. They had soon rocked to a halt. At Aurum's command, the Marula were dismounting and unhitching their lances from their saddle-chairs. He watched Aurum shape them into a cordon across the road, facing back the way they had come where there was a tower tiny in the distance. He began to feel the heat. His mask felt as if it was sliding off his sweating face. The Guarded Land's spicy odour hung heavy in the air. It had been there all day, every time they stopped. He gazed out across the land, a becalmed ocean of dust. He walked his aquar to the parapet to look down onto the road. Its smells rose up, reminding him of the weary journey from the sea. The road was too large for the traffic. Its glaring white was only half skinned over with people. He lifted his head high and sniffed the exhalation of the land. Musky earth, pungent hri fields, an undercurrent of human dung.

Near him the Marula were fidgeting. Over their heads he saw a tiny figure melting towards them in the heat. Its little flame grew slowly larger until he could hear the rhythmic scratching of claws. At last the rider swept up on an aquar identical to the ones they rode, streaming behind him a banner of green and black. Aurum barked an order and the Marula lowered their lances. The rider seemed blind to the thorns awaiting him but at the last moment pulled up, so that the Marula fell back from the frantic flailing of his aquar's hands.

'Way,' the rider cried, 'way!' He reached forward to stroke calmness into his aquar's neck.

The Marula waved their lance blades in his face to force him to dismount.

'Let him through,' said Aurum.

The Marula put up their weapons as they opened up a lane through their midst. Without looking at them, the rider thrust his reins into one of their hands and paced towards Aurum. As he came nearer, Aurum grew taller and the little man lost his swagger, bowing as far as his padded leather suit would allow.

'As you must know, Master, I'm a courier and none can stop me.'

'What do you carry?'

The man looked horrified. 'A… communication for the Mountain, Master.' 'From Nothnaralan?'

The courier shook his head slowly, staring all the time. The Master knows I mustn't speak.' Aurum put out his hand. 'Give it to me.' The courier took a step back from the hand as if it were a serpent's head. He looked round him as if seeing the Marula and the other Masters for the first time.