"You have the rifle, Frank."

"If not for that ape of his, I'd do it. He killed Sun, you know. He planned it; he planned it somehow. Sun knew-Sun knew what he was up to. I don't. Thank G.o.d I don't. I'm afraid, Shaw. I hear voices, whispering the most terrible things."

"That's enough, Frank."

"Of course. You don't want to wake, do you? You're in it with him. You're all as mad as each other."

"I think perhaps I should take the rifle for a while, Frank. What do you say? You could do with a rest."

Frank released the rifle without a struggle.

"I have a boy, you know. My son. In London. Studying to be a doctor, of all things. Atwood promised to pay for his education."

"Good man, Mr Frank. Good man."

Dimmick watched all of this, grinning nastily.

That night Atwood permitted them to stop and sleep if they could.

Arthur slept. When he woke-to Atwood's boot poking his shoulder-Dimmick and Frank were both gone. Atwood held up the lamp. Vaz was still asleep. Payne sat upright, staring fixedly at his boots.

What appeared to have happened was that Frank had murdered Dimmick in the night, killing him with his own ice-axe while he slept. Some bloodstains, snagged threads, and other clues suggested that Frank had then wrapped Dimmick's body in a blanket and rolled it over the rocks into a creva.s.se, before fleeing into the darkness, where probably he, too, had ended up in a creva.s.se. The motive was unclear. Mutiny of a sort, presumably. Madness. Revenge. n.o.body had much interest in investigating further.

"I thought Dimmick might outlast us all," Arthur said.

"He had his strengths," Vaz said, judiciously.

"See here," Atwood said. He crouched down and held the lamp low. There were b.l.o.o.d.y bootprints on the rock next to where Atwood had been sleeping.

"He meant to kill me, too, as I slept. Gentlemen, did you know what he planned? Know this: if I die, you are at the mercy of this place."

"Don't threaten us, Atwood. We've come this far with you. We'll see it through. What other choice do we have?"

"I know, Shaw. I know. I'm sorry."

Suddenly, and to Arthur's surprise and disgust, it looked as if Atwood might be about to cry.

"You've been a good friend to me, Shaw."

"Well, Atwood. Well. If you say so."

"I shall miss Dimmick; he would have been very useful in what's to come. My trials are not done."

They were already on the march again when the sun rose. At their current dizzying elevation, the sunrise was a sudden explosion of blazing violet light. It revealed that a field of glittering flint lay before them, and in the middle distance, there was a ruin.

It was much larger than the tower they'd explored in the lowlands. Sweeping walls enclosed a dozen smaller structures: a strange too-steep dome and a scatter of broken towers. A bewildering profusion of sharply perpendicular objects-crenellations? fortifications? spires? obelisks? ornaments?-somewhat recalled the Houses of Parliament. The outer wall's stone was laced with flint or mica or crystal, and with the full force of sunrise falling on it, it shone as if it were on fire. The whole structure stood on the edge of a wide impa.s.sable creva.s.se. A sheer cliff loomed behind it. Beyond that, the mountain continued to rise for mile after mile into streaming black clouds.

There was no time to study it. Atwood clapped his hands together and croaked, his voice suddenly choked with relief, or joy, or fear. There! It exists! At the same moment, Payne cried out and fired his rifle into the air. Arthur turned to see what he was shooting at.

A thousand miles of sunlit geography lay behind them. Terrain that had seemed flat and monotonous as they marched revealed itself, when seen from above, as an endless rolling sea of hills. Valleys they'd crossed revealed themselves as hundred-mile shadows, ancient gouges in the face of Mars, radiating outwards in every direction.

Payne lifted his rifle to the sky and fired again. There were wings overhead, blue and red and purple. Six, seven, eight Martians, maybe more, airborne, just a few hundred yards away. They'd been circling in the dark, waiting for dawn to reveal their prey. Now they descended. A strange sawing hum filled the air; Arthur recognised it now as the sound of Martians in flight.

Payne reloaded, fired again. His third shot caught one of the Martians square in the chest, and it fell from the sky.

"Not now," Atwood shouted. "Not now! Run, run all of you, run!"

He ran for the shelter of the ruin, and Arthur followed, scrabbling over the sharp stone. The sun was behind him and his shadow was long and sharp before him, legs and arms madly stretching and shrinking, shrinking and stretching. Long wing-shadows streamed closer. The castle ahead was almost too bright to look at, and the glare underfoot nearly blinded him. The wings were so close that the glitter in the stones underfoot reflected beads of blue.

Arthur ran in great bounding leaps, sliding and skidding on the stones. The pack on his back threatened to tip him head over heels or side to side. Wings whirred. Something swept with a rush of wind over his head. Then he stumbled, gasping, and one of them had seized his collar in its fist. For a moment he thought it might lift him into the air, like a hawk with a mouse; but it clearly hadn't reckoned with his weight. Starved as he was, he was still three times the spindly Martian's weight. He remained earthbound and the thing went heels-over-head. A blue face fell upside down past him, silver eyes wide with astonishment. It sprawled along the stones. He skidded on its splayed wings-an eerie, icy sort of surface.

He came to the ruin's outer wall. True to form, there was no door, only high windows, in one of which stood Atwood, his hand outstretched.

"Jump, Shaw!"

He jumped with all his strength, thanking G.o.d for Martian gravity. Atwood caught his hand and pulled him into darkness. A moment later Vaz fell on top of him, then Payne.

Chapter Thirty-eight.

As the sun rose and its angle shifted, the field of stones grew dim again.

Orpheus, who'd severely underestimated the weight of an Earthman, was bruised and bloodied and somewhat humbled by his roll over the stones.

Hestia was dead.

Poet and Far-Traveller lifted her up by her arms, and together the whole party rose and hurried her away from the plain of stones. They flew sunwards. The ruin shrank beneath them.

~ Dead, Orpheus said.

~ Yes, Josephine said. They have weapons ...

It was no easy matter to explain what a gun was. The Martians had few tools, made little use of fire, and regarded their own bodies and minds as quite adequate weapons. The concept of a machine for a killing was foreign to them.

~ Like something the Eye might have made, Orpheus said. He was appalled, terrified. ~ You didn't tell us.

She said nothing. It was true. It had never occurred to her that the humans might be armed.

~ We should have acted sooner. We should have swooped on them in the dark.

They'd caught sight of the expedition's lantern during the night. She had persuaded them to wait until morning to act, in the hope that by daylight they might be able to avoid violence.

~ How far? How far can they kill?

~ I don't know. Not this far.

~ Those are your people?

~ I think so.

Orpheus asked no more, and looked away from her.

They rose in silence, save for the sound of their wings.

She hadn't been able to see them clearly as they ran. The glare from the sunrise reflecting off the stones had made them into silhouettes. Ragged shadow-shapes, clumsy flailing arms and legs, bobbing heads; she could hardly tell one from another. She thought she might have seen Atwood, standing in the window of the ruined wall. Bearded, wild, sunburned, bruised; had it been Atwood? She couldn't be sure. Perhaps one of the others was Arthur. Perhaps not.

~ They killed Hestia, Orpheus said.

~ Yes.

~ Why?

~ They were afraid of us, she said. We came on them too suddenly. They are lost in a strange place and they cannot tell us from the ones who attacked them.

~ Or they are mad already. They have crawled about on the surface too long and gone mad. We'll kill them if we must.

~ No!

~ No?

~ Let me talk to them. Isn't that why I'm here?

~ Talk if you can. They won't listen.

They went up and up until the air thinned and the sky grew black and cold. The peak of the mountain-top was still far above them. Below them, the valleys were like a rough blue sea, and the ruin was a distant ship lost in a storm.

When they could go no higher, they dropped Hestia. She fell fast and was lost to sight almost at once.

It was a kind of honour, as Orpheus saw it; to end in motion, swallowed up by the face of Mars.

They circled over the ruin, descending slowly. n.o.body fired on them.

The walls described a half-moon, cut off by the creva.s.se at the rear. Towers stuck up at precarious angles. A strange, steeply swelling dome was cracked through, revealing a vault of dust below. Barbicans and watchtowers sat at the edges of the outer walls. The structure was divided in the middle by a wide open courtyard, which was choked with dust, dirt, rubble, the tops of half-buried obelisks, carved with worn illegible designs.

It was by far the largest structure Josephine had seen on Mars, and by Martian standards it was squat and ugly. It had a forbidding and warlike aspect, a little like a castle, or perhaps a battleship. A place fit for giants, or for the imprisonment of monsters.

What was it? Perhaps Hestia could have told them. All that they knew was that it had once belonged to the Nation of the Eye, who had claimed the mountain as their territory. It might have been a fortification, or a laboratory, or a temple, or any number of things. No telling what secrets it might hold. No telling what Atwood might be looking for down there.

They entered through the crack in the great bulging dome at the northern end of the complex, and were quickly lost in a maze of shadowy dust-choked corridors.

THE.

NINTH AND FINAL.

DEGREE.

Chapter Thirty-nine.

"b.l.o.o.d.y things are moving again," Payne said, lifting his rifle.

Vaz scrambled to his feet and joined Payne at the window.

"Where?"

They stood in what they'd dubbed the South Gallery, a long row of arched windows with a commanding view of the courtyard. Payne and Vaz had the rifles. Arthur had an ice-axe, which was good enough, in his opinion: if one of the b.l.o.o.d.y things got in through the window, he'd rather have an axe in his hand than a rifle.

He didn't see what Payne was pointing at. It was twilight, and the towers and crenellations and b.u.t.tresses and arches and whatchamacallits around the courtyard were so numerous and so oddly shaped that they were easy to mistake for enemies on the move.

"There. Follow my b.l.o.o.d.y-there!"

Payne fired, swore, worked the lever, and fired again. Nothing moved.

Vaz lowered his rifle, and Arthur relaxed his grip on his axe.

They'd been in the castle for a day. Following a brief, chaotic mid-morning skirmish, in the course of which Payne had put a bullet in a Martian's leg, the battle-lines had been clearly drawn. The Earthmen held the southern part of the complex, and the Martians the north. In between them was the gloomy, windswept courtyard.

"They're patient, by G.o.d," said Payne. "Cunning-not like the last lot. This lot have a notion they can wait us out. And they've learned to fear rifles. Rightly so. I always say: G.o.d may abandon you in heathen country, but Mr Winchester never will!"

The prospect of something to shoot had rather raised Payne's spirits. Since they'd been in the castle he'd been dispensing military advice, barking orders, and playing look-out, eagerly expecting further sorties from the Martian lines. None had come since evening, but sometimes one or two of the Martians circled high overhead, out of rifle range. Otherwise, they kept themselves hidden.

The southern part of the complex was a honeycomb of dust-choked corridors, sloping chimneys, vaults open to the sky. Floors had apparently been considered a luxury on Ancient Mars; for the most part, if an Earthman wanted to get anywhere he had to tightrope-walk across uneven stone beams. If they chose to, the Martians might sneak in from any direction, from above or below. That they hadn't was something of a mystery. Payne's theory was that they were too superst.i.tiously terrified of his Winchester rifle.

"Perhaps they're asleep," Vaz said. "G.o.d-I wish I were asleep."

Vaz leaned his rifle against the wall and sat back down on the floor. He poked glumly at his left boot. It had been much abused on the long march, and the race for the castle had been the final straw-now the sole flapped loose. He would be marching no farther on it. For a while he had pretended manfully to find this amusing.

"For all we know, they don't sleep," Arthur said. "We don't know a b.l.o.o.d.y thing about them. Least of all what they want with us."

"Makes no difference," Payne said. "There's them and there's us. That's all there is to know-except that we have guns and they do not."