One boat was to remain with three men aboard. These would wait until three hours had passed. If the others had not returned by then, the three were to take their boat back to the Roolanga and the next phase would begin.

Ishmael led the band to the next level, which was much like the lower one. The corridor, however, was twice as long as the one beneath it. And the one above that was double the length of the one below it.

Booragangah seemed to be built much as Zalarapamtra was. This, too, would have had an upside-down pyramid-like appearance if a cross-section had been cut in it. The next level should be twice as long as the one below it, and it was. This, however, was lit here and there with torches or with the less bright but low-oxygen-using fireflies. The torches or cages were set in stone rings carved out of the wall. The few people within were sleeping.

They passed on. It might have been best to kill the slaves, but there was always the chance that one would wake and cry out. And these were not going to attack the invaders if they should be forced back this way. They would stand to one side and let invaders and invaded fight it out.

The Zalarapamtrans proceeded more swiftly. The fact that the layout of the tunnels was much like that of their own city assured them that they could find the way to the temple. They went up the next stairway and turned to the left to go in toward the mountain. But Ishmael and two others went ahead without torches and with knives ready while the others waited below. This corridor was dark, and a few random explorations of chambers along the way disclosed more storerooms, one of them an arsenal. These contained no weapons which the band did not have.

The party went to the other end of the corridor. This did not end in a wall, as the others did, but in another staircase. Namalee said that she expected this, since the corridor of her city on this level also had a staircase.

"This should lead up to another corridor at the end of which is another stairway to still another corridor. But that one will lead to the temple of the gods. Only..."

"Only what?" Ishmael said.

"A long time ago, when even my great-grandparents were not yet born, a Zalarapamtran escaped from Booragangah. He told some strange stories. One says that there are guardians of the temple of the gods of Booragangah. Not human guardians. Beasts that the founder of this city, the hero Booragangah himself, could not kill. So he left them here in places where the unwary would encounter them, and --"

"We've no time for folk tales," Ishmael said. But when he had climbed the next staircase and looked around the corner, he was not so sure that there was not something strange in this place.

This hallway, unlike the others, was brightly lit. Torches and cages of fireflies were set within stone rings every six feet, two cages for every torch. The hallway ran deep into the shelf, or into the mountain, for he was not certain how deeply they had penetrated. At the far end the corridor tilted upward. The lower end was still visible, however, and something across it flickered brightly in the torchlight.

Ishmael finally stepped out from around the corner. The air passed across his face like a cold hand. At the junction of wall and floor were many holes about six inches across. Apparently these were shafts drilled through to the bottom of the shelf. He did not know what caused the air to move. What did come to him was a vision of the ledge drilled through with many holes and the tiny cracks that had to be developed in the ledge with the constant vibration of earthtides and quakes and the cracks spreading and reaching the shafts and then, inevitably, a great piece of the ledge falling off.

He walked ahead of the others, while those who had been given bows strung them. It was time for them, now that they were approaching a place where they knew the enemy would be up and armed.

The end of the corridor behind them was a blank wall, and there were no doorways or archways along the walls. They passed by the torches and caged fireflies and started up the slope. At the end was a square-cornered opening about seven feet high and six feet wide. Across it was a spiderwebbish arrangement of gray strands bearing little bits of mica-like material. It was these that flickered in the shifting light of the torches.

"What is that?" Ishmael whispered.

"I do not know," Namalee said.

Ishmael took a torch from a man and stepped up close to the web and peered through it. The torch threw the shadow of the strands onto the floor behind it. Beyond was a vast darkness.

Ishmael hesitated. The web looked so fragile that he could not imagine why it had been set there. Or would breaking it set off an alarm, as the shaking of a spider's web transmitted vibrations to the waiting predator? If he burned it with his torch, and so avoided touching it, he still might release tension on strands connected to the web and leading back into the darkness. And the release of tension would awaken something in there.

He passed the torch across the face of the web and the flames licked them out of existence. The mica-stuff fell to the floor like metallic snowflakes.

A thrumming sound, faint but deep, came from the darkness.

Holding the torch ahead of him, Ishmael stepped through the doorway.

The light opened its own path. The room was even larger than he had thought. The ceiling was so high that the torchlight could not reach to it, and the walls receded at a slant into invisibility. Before him was a smooth stone floor that stretched into the heart of the mountain, or at least looked as if it did.

The air, however, was motionless, musty and warm. There were no shafts sunk along the walls.

The others came through the entrance and gathered behind him. Four held torches, and these pushed the darkness back more. But the ceiling was still shrouded, and the walls departed to the right and the left at an ever-increasing angle.

Namalee spoke very softly behind him. "It is said that when Booragangah led his people to this place, he found that others had lived here before him. There were some large chambers cut into the mountain itself and some perilous beasts living in them. The original inhabitants had died out or been killed by the perilous beasts. Booragangah slew some, but the others were too strong for him. So he shut them up, and his people cut other rooms and halls into the rock of the great ledge."

"Doubtless the story contains some elements of truth," Ishmael said. "But if there are any beasts here, they do not seem to have been shut up. How could that web hold anything in?"

"I do not know," she said. "But it might have an odor that we can't detect but that the beast can. Or there may be some other explanation."

Their whispers seemed to fly out like bats into a never- ending night. The darkness was absorbent; it sucked in everything, light, sound and, given a chance, it might suck in their bodies.

Ishmael, stepping forward again, holding the torch above him, was reminded that he really knew little of this world. Though he had crossed vast distances on it and seen strange things, he had become accustomed to much of it. But there must be many sinister things in this world, things which he would be ill-prepared to cope with because he would not understand their nature.

He went on. The torches were burning ships falling in the night. Darkness split ahead of them and fused behind them. And the stillness and silence continued.

After a while, Ishmael got the impression that the darkness was breathing. It was as if the darkness were itself an entity, a gigantic animal without form which lived on all sides of them.

Ishmael looked back at the doorway. It was a block of light -- but not the solid block it had been after he had burned off the web.