The door did not lead to the same corridor, or even the same kind of corridor Ross had passed through moments earlier. Instead they entered a short passage with walls of some smooth stuff which had almost the sheen of polished metal and were sleek and cold to the touch. In fact, the whole place was chill, chill as river water in the spring. Still herding the prisoner before him, Ross came to the nearest door and looked within, to be faced by incomprehensible frames of metal rods and boxes. Rossa of the traders marveled and stared, but again, he realized that what he saw was not altogether strange. Part of one wall was a board on which small lights flashed and died, to flash again in winks of bright color. A mysterious object made of wire and disks hung across the back of a chair standing near-by. The bound man lurched for the chair and fell, rolling toward the wall. Ross pushed him on until he was hidden behind one of the metal boxes. Then he made the rounds of the room, touching nothing, but studying what he could not understand. Puffs of warm air came in through grills near the floor, but the room had the same general chill as the hall outside. Meanwhile the lights on the board had become more active, flashing on and off in complex patterns. Ross now heard a buzzing, as if a swarm of angry insects were gathered for an attack. Crouching beside his captive, Ross watched the lights, trying to discover the source of the sound. The buzz grew shriller, almost demanding. Ross heard the tramp of heavy footgear in the corridor, and a man entered the room, crossing purposefully to the chair. He sat down and drew the wire-and-disk frame over his head. His hands moved under the lights, but Ross could not guess what he was doing. The captive at Murdock's side tried to stir, but Ross's hand pinned him quiet. The shrill noise which had originally summoned the man at the lights was interrupted by a sharp pattern of long-and-short sounds, and his hands flew even more quickly while Ross took in every detail of the other's clothing and equipment. He was neither a shaggy tribesman nor a trader. He wore a dull-green outer garment cut in one piece to cover his arms and legs as well as his body, and his hair was so short that his round skull might have been shaven. Ross rubbed the back of his wrist across his eyes, experiencing again that dim other memory. Odd as this man looked, Murdock had seen his like before somewhere, yet the background had not been Gurdi's post on the southern river. Where and when had he, Rossa, ever been with such strange beings? And why could he not remember it all more clearly?