The four machine men found themselves in a maze of dead branches through which they threaded their way with difficulty, often finding the way before them too impenetrable and closely woven for passage. The professor now and then had to use his heat ray. They struck the rock foundation of the continuous nest thirty feet down, and they followed a devious route to the edge of the crag. They found a long, steep descent, dangerous and treacherous. Luckily, none of the Quari returned to attack them until they were safely at the bottom of the looming crag. "It is a long way down the mountain and then to the spaceship," said the professor, "but we must try and make it in what little time we have left." "If nothing detains us, it will be enough, I believe." From what they knew of Ajiat's rotation--they had all made separate computations while prisoners of the Ajirs--they had come to the same conclusion regarding the time left before the sun exploded. Now, there were only three of Ajiat's rotations left before the meteoric mass struck the sun! * * * * * All that day, they kept moving down the mountain, and though they were going downhill, they nevertheless felt the effects of the strong gravity. They occasionally reached ledges or precipices which had to be avoided. Once, 29G-75 fell over one of these ledges, and although the fall was a relatively short one for a machine man to sustain--the mighty attraction of Ajiat drew him down so forcefully that he bent a leg in under him in his fall. All day long, at intervals, the Quari came to bother them, generally desisting when they found that they were not edible. At night, although they used their body lights, their progress slowed somewhat. Dawn came, and they increased their pace once more. Untiring, they knew no cessation until a vital part wore out. This, the professor and his companions constantly feared. Again, the sharp eyes of the Quari saw them from on high and came to harass them again. Sometimes the professor managed to drive them off with his heat ray. The machine men also struck them with lashing tentacles, but they were so large that this had little effect on them. Shortly after noon, disaster stalked them. Earlier fears were realized. The leg which 29G-75 had bent in his fall finally wore so bad at the joint with his metal body that it became useless. This slowed their descent of the mountain. Up to this point, the professor had figured themselves well ahead of the impending, solar catastrophe. Night fell again. They kept on, assisting the slightly unbalanced 29G-75 over difficult stretches.