Burl walked around the little enclosed space. "I guess I'm a prisoner here," he said. "This dome is on the surface. Most of the area is just a sort of rocky plain with patches of liquid gases, but there are a couple of big buildings nearby. Funny sort of structures--they have fancy tops with symbols on them that look like the phases of the moon." "I think I'm inside one of those buildings," Russ guessed. "I'm in a big hall with a lot of exhibits in glass cases. And they've got the strangest creatures I've ever seen in them. There are lunar markings here, too--they remind me of the ones we saw on Pluto. You know what I suspect?" Burl paced around, regaining his senses as he walked. It was obvious that, after he'd been knocked out by the Plutonians, he had been taken by them to this moon of Neptune. For what purpose? Russ continued to murmur his thoughts, his voice ringing tinnily in Burl's earphones. "I think that Triton was originally Pluto's moon. When Pluto wandered into the solar system, it crossed Neptune's orbit and was held. Its moon came closer to Neptune and was captured completely. But Pluto, having a greater mass, didn't stick. It established an eccentric orbit of its own which took it far out from Neptune for hundreds of years at a stretch and brought it back only rarely. Pluto lost its moon. And that moon was the spiritual home of the Sun-tappers' religion." Burl glanced across the landscape. There were some funny things growing nearby. They looked a little like thin, glassy trees with big, blue coconuts on top. "What happened to you and Haines after we got separated?" he asked, still talking through his helmet phone. "I don't know what happened to Haines," said Russ. "I hope he got away. But they trapped me. I was taken aboard one of their dumbbell ships, and brought here. The trip took days. I guess you were unconscious for all that time. If it's any comfort to you, the Pluto building was destroyed. Our atomic bomb went off. I saw the flare from a window in the ship. I think this moon is the last stronghold of the Sun-tappers, and I think it is our final objective." The strange crystalline vegetation seemed to be moving closer to Burl. He watched it carefully. It _was_ moving! There were living beings out there! They glided oddly over the ground, and he saw that their bases were a mass of crystalline fringes, moving feelers which crawled over the surface bearing the upper structures with them. They had thin, trunklike bodies with two long, pencil-like branches that were used as arms. And the coconut objects were heads! They circled the dome now, and Burl could see that each round blue knob had a central black spot that apparently served as an eye. There was no sign of nostrils or mouth. Burl stared at the creatures in wonder. The beings were clearly gesturing to him, trying to signal with their odd arms. He waved back, wondering how he could establish communication. As he did so, he described the creatures to Russ.