"What you see is the Niss Command Center. It lies in another world than this, but here is the multihedron of intersection. They bring their harmonic generators to bear here in the hope of establishing an aperture of focus."
"I don't understand half of what you're saying, Bram. And the rest I don't believe. But with this staring me in the face, I'll have to act as though I did."
Suddenly the wall cleared. Like a surface of moulded glass the stone threw back ghostly highlights. Beyond it, the Niss technicians, seen now in sharp detail, worked busily, silently, their faces like masks of ridged red-brown leather. Directly opposite Bram's Repellor, an apparatus like an immense camera with a foot-wide silvered lens stood aimed, a black-clad Niss perched in a saddle atop it. The white light flooded the cave, threw black shadows across the floor. Bram hunched over the Repellor, face tensed in strain. A glow built in the air around the Niss machine. The alien technicians stood now, staring with tiny bright-red eyes. Long seconds passed. The black-clad Niss gestured suddenly. Another turned to a red-marked knife-switch, pulled. As suddenly as it had cleared, the wall went milky, then dulled to opacity. Bram slumped back, eyes shut, breathing hoarsely.
"Near were they then," he muttered, "I grow weak...."
"Let me take over," Tremaine said. "Tell me how."
"How can I tell you? You will not understand."