"If that ash is anything like what it was in Nyissa, we're going to be wandering blind out here, Belgarath," Barak said.

"Don't worry about it," the sorcerer replied. "I've got a lock on Rak Cthol. The Grolims aren't the only ones who can locate things that way. Let's move out."

They started along the ridge again as the cloud blotted out the sky overhead. The thunder shocks were a continuous rumble, and lightning seethed in the boiling cloud. The lightning had an arid, crackling quality about it as the billions of tiny particles seethed and churned, building enormous static discharges. Then the first specks of drifting ash began to settle down through the icy air, as Belgarath led them down off the ridge and out onto the sand flats.

By the end of the first hour, Garion found that holding the image in his mind had grown easier. It was no longer necessary to concentrate all his attention on it as it had been at first. By the end of the second hour, it had become no more than tedious. To relieve the boredom of it as they rode through the thickening ashfall, he thought about one of the huge skeletons they had passed when they had first entered the wasteland. Painstakingly he constructed one of them and placed it in the image he was holding. On the whole he thought it looked rather good, and it gave him something to do.

"Garion," Aunt Pol said crisply, "please don't try to be creative."

"What?"

"Just stick to sand. The skeleton's very nice, but it looks a bit peculiar with only one side."

"One side?"

"There wasn't a skeleton on my side of the image - just yours. Keep it simple, Garion. Don't embellish."

They rode on, their faces muffled to keep the choking ash out of their mouths and noses. Garion felt a tentative push against the image he was holding. It seemed to flutter against his mind, feeling almost like the wriggling touch of the tadpoles he had once caught in the pond at Faldor's farm.

"Hold it steady, Garion," Aunt Pol warned. "That's a Grolim."

"Did he see us?"

"No. There - he's moving on now." And the fluttering touch was gone.

They spent the night in another of the piles of broken rock that dotted the wasteland. Durnik once again devised a kind of low, hollowed-out shelter of piled rock and anchored-down tent cloth. They took a cold supper of bread and dried meat and built no fire. Garion and Aunt Pol took turns holding the image of empty sand over them like an umbrella. He discovered that it was much easier when they weren't moving.

The ash was still falling the next morning, but the sky was no longer the inky black it had been the day before. "I think it's thinning out, Belgarath," Silk said as they saddled their horses. "If it blows over, we'll have to start dodging patrols again."

The old man nodded. "We'd better hurry," he agreed. "There's a place I know of where we can hide - about five miles north of the city. I'd like to get there before this ashfall subsides. You can see for ten leagues in any direction from the walls of Rak Cthol."

"Are the walls so high, then?" Mandorallen asked.

"Higher than you can imagine."

"Higher even than the walls of Vo Mimbre?"

"Ten times higher - fifty times higher. You'll have to see it to understand."

They rode hard that day. Garion and Aunt Pol held their shield of thought in place, but the searching touches of the Grolims came mare frequently now. Several times the push against Garion's mind was very strong and came without warning.

"They know what we're doing, father," Aunt Pol told the old man. "They're trying to penetrate the screen."

"Hold it firm," he replied. "You know what to do if one of them breaks through."

She nodded, her face grim.

"Warn the boy."

She nodded again, then turned to Garion. "Listen to me carefully, dear," she said gravely. "The Grolims are trying to take us by surprise. The best shield in the world can be penetrated if you hit it quickly enough and hard enough. If one of them does manage to break through, I'm going to tell you to stop. When I say stop, I want you to erase the image immediately and put your mind completely away from it."

"I don't understand."

"You don't have to. Just do exactly as I say. If I tell you to stop, pull your thought out of contact with mine instantly. I'll be doing something that's very dangerous, and I don't want you getting hurt."

"Can't I help?"

"No, dear. Not this time."

They rode on. The ashfall grew even thinner, and the sky overhead turned a hazy, yellowish blue. The ball of the sun, pale and round like a full moon, appeared not far above the southwestern horizon.

"Garion, stop!"

What came was not a push but a sharp stab. Garion gasped and jerked his mind away, throwing the image of sand from him. Aunt Pol stiffened, and her eyes were blazing. Her hand flicked a short gesture, and she spoke a single world. The surge Garion felt as her will unleashed was overpowering. With a momentary dismay, he realized that his mind was still linked to hers. The merging that had held the image together was too strong, too complete to break. He felt himself drawn with her as their still joined minds lashed out like a whip. They flashed back along the faint trail of thought that had stabbed at the shield and they found its origin. They touched another mind, a mind filled with the exultation of discovery. Then, sure of her target now, Aunt Pol struck with the full force of her will. The mind they had touched flinched back, trying to break off the contact, but it was too late for that now. Garion could feel the other mind swelling, expanding unbearably. Then it suddenly burst, exploding into gibbering insanity, shattering as horror upon horror overwhelmed it. There was flight then, blind shrieking flight across dark stones of some kind, a flight with the single thought of a dreadful, final escape. The stones were gone, and there was a terrible sense of falling from some incalculable height. Garion wrenched his mind away from it.

"I told you to get clear," Aunt Pol snapped at him.

"I couldn't help it. I couldn't get loose."

"What happened?" Silk's face was startled.

"A Grolim broke through," she replied.

"Did he see us?"

"For a moment. It doesn't matter. He's dead now."

"You killed him? How?"

"He forgot to defend himself. I followed his thought back."

"He went crazy," Garion said in a choked voice, still filled with the horror of the encounter. "He jumped off something very high. He wanted to jump. It was the only way he could escape from what was happening to him." Garion felt sick.