saw what he had noticed before: Schroeder's black hair was coming out light brown at the roots. It was a color that would better match his light complexion and it was the color of hair that a man named Schrader, wanted by the police on Venus, had had. Hair could be dyed, identification cards could be forged—but it was all something Prentiss did not care to pry into until and if Schroeder gave him reason to. Schroeder was a hard and dangerous man, despite his youth, and sometimes men of that type, when the chips were down, exhibited a higher sense of duty than the soft men who spoke piously of respect for Society—and then were afraid to face danger to protect the society and the people they claimed to respect. A lone prowler came on the eleventh night following the wall's completion. It came silently, in the dead of night, and it learned how to reach in and tear apart the leather lashings that held the pointed stakes in place and then jerk the stakes out of their sockets. It was seen as it was removing the third stake—which would have made a large enough opening for it to come through—and shot. p. 33 It fell back and managed to escape into the woods, although staggering and bleeding. p. 33 The next night the stockade was attacked by dozens of prowlers who simultaneously began removing the pointed stakes in the same manner employed by the prowler of the night before. Their attack was turned back with heavy losses on both sides and with a dismayingly large expenditure of precious ammunition. There could be no doubt about how the band of prowlers had learned to remove the stakes: the prowler of the night before had told them before it died. It was doubtful that the prowlers had a spoken language, but they had some means of communication. They worked together and they were highly intelligent, probably about halfway between dog and man. The prowlers were going to be an enemy even more formidable than Prentiss had thought. The missing stakes were replaced the next day and the others were tied down more securely. Once again the camp was prowler proof—but only for so long as armed guards patrolled inside the walls to kill attacking prowlers during the short time it would take them to remove the stakes. The hunting parties suffered unusually heavy losses from prowler attacks that day and that evening, as the guards patrolled inside the walls, Lake said to Prentiss: