The lights that Kreacher had turned on were lanterns that now shone with a bright green flame, and they illuminated a frieze on the wall containing images of snakes and serpents in various guises. The floor was smooth marble and man-made, as he had expected. Astor wondered how far he had wandered from his prison. He looked around to see if he could see a boulder and chain of any kind but could see nothing on either side of the long corridor.