The jets blew sand in their faces as the capsule rose and vanished. Jason held the light while Kerk tied the plaited leather rope to the end of the stained nylon line, then stowed this in the backpack, along with the rest of the equipment that Jason would use during the climb. Behind them, as they rode back to the encampment, the first light of dawn touched the horizon.

When the Pyrrans marched up The Slash, they saw that a desperate battle had been fought during the night. The dam of rubble and rock still sealed the neck of the valley, but now it was sprfnkled darkly with corpses. Soldiers slept on the ground, out of bowshot of the enemy above, many of them wounded. A bloodstained nomad, with the totem of the lizard clan on his helm, sat impassively while a fellow clansman cut at the bone shaft of the arrow that had penetrated his arm.

“What happened here?” Jason asked him.

“We attacked at night,” the wounded soldier said. “We could not be quiet because the rocks slipped and rolled away while we climbed, and many were hurt in this way. When we were close to the top, the weasels threw bundles of burning grass on our heads and they were above us on the clifftop in the darkness. We could not fight back and only those who were not high on the rocks lived to come down again. It was very bad.”

“But very good for us,” Kerk said as they moved on. “Temuchin will have lost prestige with this defeat, and we will gain it when we climb the rock. If we can—”

“Don’t start the doubting act again,” Jason said. “Just stand by at the base here and pretend that you know exactly what is going on.”

Jason took off his heavy outer clothing and shivered. Well, he would warm up quickly enough as soon as he started his ascent. From below the tower looked as unclimbable as the side of a spaceship. He was tying the piton hammer’s thong around his wrist when Ahankk walked up, his face working as he tried both to sneer and to look dubious at the same time.

“I have been told, jongleur, that you are so stupid you think you can climb straight up rock.”

“That is not all you have been told,” Jason said, slipping his arms through the pack straps and settling the pack on his back. “Lord Temuchin told you to come here to see what happens. So get comfortable and rest your legs for the moment when you must run to your master with the glad news of my success.”

Kerk looked up dubiously at the vertical face of rock, then down at Jason. “Let me climb,” he said. “I am stronger than you and in far better condition.”

“That you are,” Jason agreed. “And as soon as I get to the top, I’ll throw down the rope and you can climb up with all the bombs. But you can’t go first. Rock climbing is a skilled sport, and you are not going to learn it in a few minutes. Thanks for the offer, but I’m the only one who can do this job. So here we go. I would appreciate a lift so I can get a grip on that small ledge right over your head.”

There was no nonsense about climbing up onto the Pyrran’s shoulders. Kerk just bent and seized Jason by the ankles and lifted him straight up into the air. Jason walked his hands up the stone face as he rose and grabbed onto the narrow ledge while Kerk steadied his feet. Then his toes scrabbled and caught on a protruding hump and the climb had begun.

Jason was at least ten meters above the ground before he had to drive his first piton. A good bit of ledge, wide enough to lie down on, was well beyond the reach of his outstretched fingertips. The rock surface here was interlaced with cracks, so he picked a transverse one at the right height before him. The first piton was one of the disguised ones; he jammed it into the crack. Four sharp blows with the hammer wedged it in solidly. Slowly and carefully — it had been a good ten years since he had done any real climbing, he stepped out and eased his weight onto the piton. It held. He straightened his leg, sliding up the rough surface of the rock until he could reach the ledge. Then he pulled himself up to a sitting position and, breathing heavily, looked down at the upturned faces below. All of the soldiers were looking at him now, and even Temuchin had appeared to watch the climb. The enemy was surely taking an interest in what was happening, but the swell of the rock face cut them off from sight and arrow-shot. They could come to the edge of the canyon’s wall, but they could not reach him unless they climbed the tower as well.

The rock was cold and he had better keep moving.

There was no way to estimate the height accurately, but he thought he must now be at least as high as the rim of the canyon. He had his toes jammed into a wide crack and was trying to drive a piton at an awkward angle off to one side when he heard the shouting below.

He bent as much as he could and called down, “What? I can’t hear what you are saying.” As he did this an arrow cracked into the rock at the place where his head had been and spun away and fell.

Jason almost fell after it, keeping his grip only by a convulsive clutch at the ribbed surface of the rock. When he turned his head, he saw a weasel tribesman hanging from a leather strap that was tied tightly about his body. He had a second arrow notched and ready to fire. The men holding the other end of the strap were out of sight on the rim of The Slash, but by lowering the bowman below the bulging outcropping they had put him within bowshot of Jason.

The warrior carefully drew the arrow back to the point of his jaw and took aim. The hammer was tied by its thong to Jason’s wrist so he would not lose it, but he still clutched the piton in his left hand. With a reflexive motion, he hurled it at the bowman. The blunt end caught him in the shoulder. It did not injure him, but it deflected his aim enough so that the second arrow missed as well. He pulled a third from his belt and notched it to the bowstring.

Down below the soldiers were also shooting their bows, but the range was long and the overhead aim difficult. One arrow, almost spent, sank into the bowman’s thigh, but he ignored it.

Jason let go of the hammer and took out a piton. It was tempered steel, well weighted and needle sharp. And he had had one try already so he knew the range. Taking the pointed end in his fingertips he drew well back beyond his head, then threw it with all the strength of his arm.

The point caught the bowman in the side of the neck and sank deep. He let go of his bow, scratched for the weapon with his fingers, shuddered and died. His body vanished from sight as the others pulled him up.

Someone had quieted the men below and he heard Kerk’s voice cutting through the sudden silence.

“Hold on and brace yourself!” he shouted.

Jason looked down slowly and saw that the Pyrran had moved back from the base of the cliff and was holding one of their bombs, bent over and lighting it. Frantically, Jason kicked his toes in farther and, making fists of both hands, he jammed them deep into a vertical crack in the stone face.

Below him, the soldiers retreated from the base of the cliff. The foreshortened figure of Kerk reached back and back, until his knuckles appeared to be touching the ground. Then, in a single, spasmodic contraction of all his muscles, he hurled the bomb almost straight up into the air.

For a heart-stopping instant Jason thought it was coming right at him, then he realized it was going off to one side. It seemed to siow as it reached the summit of its arc, before it disappeared behind the curve of rock. Jason pushed hard against the cold stone.

The boom of the explosion was transmitted to him through the stone, a shuddering vibration. Fragments of rock and bodies blew out into space behind him and he knew his flank was safe. Kerk would be ready if the same trick were tried again. Yet there was still a feeling of unease.

“Kerk!” Jason shouted. “The piton!” He spoke in Pyrran. “What happened to the piton I dropped? If Temuchin should see it.