So Dave retraced his steps to the laboratory and inspected it. He saw nothing, and so began to feel his way through the walls of the building. He became engrossed in this job; it was both interesting and a bit terrifying to go walking through walls and feeling along the insides of beams and rafters. The building was a sort of thick phantom. Not only were the walls transparent, but the pipe lines, electrical wiring, nails, and other normally hidden bits of construction were visible within them. And walking along the length of a wall with a shoulder on either side, one in one room and one in the other, was disconcerting as well as amusing. The heavy concrete-block walls, set up for radiation barriers, were wider than Crandall's shoulder-spread, and he could walk through their length completely enclosed in the hard concrete. Here it was eerie, too, for encased in the concrete were electrical wires and pipes, to Dave no heavier than the concrete through which he walked, but none the less clearly visible. So Dave inspected the remote lab, walking down the walls and through the pipes and wires that stretched through the house like a spider's web, and he saw no evidence of espionage-- --until he caught his throat under a wire that should have been as tenuous as the others, but which almost throttled him. Dave bounded back, clutching at his throat and swearing soundly. Then he realized! And forgetting his throat, Dave followed the wire to one of the remote video and audio sets. He pulled it aside--and it split into two complete sets! There were two television cameras, identical in every way, one in Dave's world, one in the everyday world, placed in perfect register! His proof! His friends had gone; obviously back to their laboratory to prepare another crystal. Here he could get one: their next one. Then he could communicate with them and start planning a counter-offensive. Dave looked across the plain towards the main laboratory building, and shrugged. If he had a crystal now, all he could do would be to let them know he was alive and on the job, but had no information. On the other hand, he had fouled up the television camera in the remote lab, and it seemed likely that there would be a repairman coming along to see what was wrong. Just where Claverly and Phelps were in this mess Dave didn't know. But he assumed that soon after their projection into this cockeyed half-world, the enemy had come along to collect them both. Dave blinked at a sudden fantastic thought: would the flashing of a crystal send him back to his own world, or toss him along into another one? An interesting thought--to be pursued later. Right this moment the thing to do was to lie doggo until the enemy arrived to take Dave in tow. This time, instead of a baffled scientist, they were attempting to catch a gent who was more interested in being alive than in figuring out where he was.