Without any warning except a slight movement of O’Brien’s hand, a wave of pain flooded his body. It was a frightening pain, because he could not see what was happening, and he had the feeling that some mortal injury was being done to him. He did not know whether the thing was really happening, or whether the effect was electrically produced; but his body was being wrenched out of shape, the joints were being slowly torn apart. Although the pain had brought the sweat out on his forehead, the worst of all was the fear that his backbone was about to snap. He set his teeth and breathed hard through his nose, trying to keep silent as long as possible.