Feiffer's cartoon takes him one day a week to conceive and draw. During the other six days he works on his latest writing project. For three years -- until it was published this past summer -- that project was _Ackroyd_, an unconventional detective-type novel in which the characters are too human to keep their traditional roles as props for the detective's cleverness. The book is less suspenseful than a standard detective novel, but more revealing of human nature. One of the things that has been in my work for many years," says Feiffer, "is people's need to communicate with each other not directly, but in code. ... Coded language is used to guide our lives, to frame our relationships with people." Feiffer's main character takes the name Roger Ackroyd and tries to become a private detective. Instead he gets "so intertwined with the coded life of his clients that he works on that for the rest of his career." _Ackroyd_ got extremely mixed reviews. "It's what I'm used to," notes the author. "Some reviews have been glowing. Others wondered what the hell the book was about and why I bothered to write it." Feiffer takes the good and the bad in stride, remembering what happened when his first play, _Little Murders_, opened on Broadway in 1967. "It got all negative reviews and closed in a week," he recalls. "It was immediately done in London after that, which started the revival, because it was done very successfully. Then it was brought back to New York the following year and it won all the awards." In 1971 it was made into a successful film starring Elliott Gould and Marcia Rodd. An occasional theatregoer, Feiffer ends the interview on a customary depressing note, saying that he is generally disappointed by even the biggest hits in town. "I don't think of myself as a Broadway playwright," he says. "I'd be ashamed of that title. I don't think the Broadway theatre is very interesting or has been for the last 20 years." ******** EASTSIDER GERALDINE FITZGERALD Actress, director and singer 3-15-80 Anyone hearing her rasping, throaty, Irish-accented voice for the first time might think she were suffering from laryngitis. But those who have come to love and admire Geraldine Fitzgerald over the past 40 years hear nothing but earthy humanity in the voice. One of the most versatile actresses in America, as unorthodox as she is gifted, Miss Fitzgerald at 66 remains at the height of her career, constantly juggling a variety of projects, as she says, "like somebody cooking a meal with many courses." We're sitting in her Upper East Side living room, which is decorated in white from floor to ceiling -- carpet, chairs, tables, sofa, and even the television. The only picture is a childhood portrait of her daughter Susan Scheftel, now a 27-year-old graduate student.