For moments they simply drove forward without saying anything as they lost speed. "That was too close," Nathan said. "I waited too long for that shot." "You got him. That's what counts." He looked at Firebird. She was not disturbed by their narrow escape. It was obviously not in her philosophy to hold post mortems. They swung back to the blazing wreckage. The light of dawn streaked the sky before it was cool enough to approach. There was no tangible remains of the enemy who had died in the flames. "It couldn't have been Tabor. He shoots better than that," said Nathan. Firebird poked among the embers, using the pouch containing the four Jewels as an indicator. Then she caught the sparkle in the sands. It was the Blue Jewel. IX The bloody dawn of Mars lit the ruins of Pheme as they sped past it again. Though they had not slept they did not feel sleepy as daylight came. Their attack and the acquisition of the Blue Jewel left two horrible alternatives in Nathan's mind. If it had been Tabor who had attacked them surely he had not known their identity and would not have fired on them if he had. In this case, Nathan had slain his father's lifelong friend without cause. Or if it had not been Tabor it meant that Tabor possessed the sixth Jewel--the pink one--and was the murderer Nathan sought. He thrust both thoughts out of his mind and forced himself to think of the task ahead. The peaks of the Pater Mountains were not even visible on the horizon. Soon the heat of the desert day made itself felt. They switched on the air conditioning after Nathan patched the hole in the cabin housing. They ate as they drove, and in the afternoon, Firebird explained the course and they alternated driving and sleeping. Near sunset they glimpsed the distant, ominous crags of the Pater Mountains. They looked like some gargantuan graveyard where the stark bones of giants had been heaped. The wind was rising and spinning sheets of sand from the desert surface. The sandstorms of Mars are not simply the whipping, wind-driven sands of Earth. They are mighty electrical storms in which clouds of sand gather in the sky and are charged with millions of volts of potential by their ceaseless grinding against one another. It grew dark quickly with the sand clouds masking the twilight. Streamers of fire began to lace the mountain top. A continuous purple corona gave it the aspect of luminescence. The mountain rose slowly out of the desert and the sand gave way gradually to a trail of broken rocks that ground and protested against the runners of the sled. "We'll go from here on foot in the morning," said Firebird. As she brought the sled to a halt she leaped quickly out and started tugging at a huge boulder nearby. Nathan stared in puzzlement. The boulder slowly tipped on its side, exposing a small cavern. "We'll hide the sled in here. I'll show you why in the morning."