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. It fell back and managed to escape into the woods, although staggering and bleeding.

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.