Only six months ago, I discovered that, over the years, some cubby-hole editors at Ballantine Books, fearful of contaminating the young, had, bit by bit, censored some 75 separate sections from the novel. Students, reading the novel which, after all, deals with the censorship and book-burning in the future, wrote to tell me of this exquisite irony. Judy-Lynn Del Rey, one of the new Ballantine editors, is having the entire book reset and republished this summer with all the damns and hells back in place.