In Chapter One, the paragraph "I knew something was wrong with me that summer, because all I could think about was the Rosenberg's...outside the slick marble and plate-glass fronts along Madison Avenue"and the sentence "I felt very still and very empty, the way the eye of a tornado must feel, moving dully along in the middle of the surrounding hullabaloo"
are both wrapped in parentheses.
While I have not taken a more in-depth look at the text before and after this in the novel, I find this quite bizarre. The Faber editions that I have consulted do not have the above passages parenthetically trapped. In reading the novel at least once a year and switching between Faber and Harper versions, sometimes I have felt as though some of the text was new or different.