WHEN, early in Lyndon B. Johnson's presidency, Theordore H. White arrived at Washington, pursuing The Making of the President, The Oval Office reaction suggested Hannibal was crossing the Ellipse. At full voice, Johnson decreed that no friend of his would return White's calls, meet the author or look his way in restaurants. What Johnson feared was not White, but his own friends. "If my people get with him," he complained, "they'll blab, blab, blab, and next thing you know, there I'll be, in front of God and everybody, naked as a turkey egg."

In Lyndon: An Oral Biography, Merle Miller confirms his subject's fears. The author of Plain Speaking, the No. 1 best seller about Harry S. Truman, has employed the medium of oral history to assemble Johnson friends, wife, daughters and brother between hard covers; untrustworthy lot that Johnson suspected, they proceed through lively recollections to leave the late president, in fact, "naked as a turkey egg."

No secret remains. This is Lyndon Johnson true, lunging through life, pouring "every ounce of his energy" into whatever he did, ranting, raving, shouting, "screaming at the universe," flogging system, staff and self to achieve what others pronounced unachievable. Here, too, is the turkey egg: "an American Henry VIII," holding naked court in bedroom and bathroom, aiming "barnyard" language more at noses than ears, spearing food from the plate of a prime minister's wife, doing what he pleased, when it pleased him to do so. "I don't think we've ever seen the likes of Lyndon Johnson before," Miller concludes , "and I doubt we will ever again."

The book is not pro or anti, no critique of Vietnam. Miller's quarry is the man who, until now, has eluded biographers; trailing unobtrusively in the background, Miller allows his posse of turncoats -- 336 in all, myself among them -- to lead him to the Johnson few ever knew: at his best, magnificent; at his worst, outrageous.

In the Oval Office, about to appoint the first Mexican-American to the federal bench, an emotional Johnson towers over his nominee, Rinaldo Garza: "I want you to be the greatest judge in the World. When you walk down the streets of Brownsville, the most miserable little Mexican children will look up as if it was the second coming of Jesus Christ Himself. 'There's Justice Garza! There's Justice Garza!'" Garza, by now crying, is so shaken that, Ramsey Clark Testifies, "it took him five years before he could do a mean thing."

At the White House, a young aide enters the presidential bedroom to find quite another Johnson, lying on his side in the high four-poster bed, facing an assembled court. With everyone pretending nothing unusual is afoot, Johnson dictates to his secretary converses with his wife, yells at Bill Moyers, has words with a network person as, all the while, a nurse at the presidential backside administers an enema.

Johnson would handle this story easily. "It's all a lie," he would shout, "I was not yelling at Bill Moyers." Others from the Johnson world will be -- already are -- troubled over his book, at the friends for their "blab, blab, blab," and at Miller for not applying rouge and powder. They should not agonize. Truth, told here without malice, makes Johnson a larger, more appealing, figure. "He was not a ballet dancer," Hubert H. Humphrey says. "He had all the weaknesses and strengths of a big man." Lyndon, in my view, is fair about both qualities.

Miller is the first established author to under-take a birth-to-death biography of Johnson. It is useful to a better understanding of the man who, as president, came suddenly and left abruptly. First in Washington when Herbert Hoover was president, Johnson's tour bracketed the national careers of both Harry S. Truman and John F. Kennedy. Over that long span, he was never far from the center of large events, shaping and reshaping the nation. It is a broad canvas;" Miller fills it, crowds it, with the richest store of political anecdotage -- more than 1,000 recollections -- in years.

Oral history serves the Johnson story especially well. So often the youngest man ever at the different stations of his career, Johnson was not yet 60 -- 10 years younger than Ronald Reagan -- when he renounced a bid for a second term as president. Most of his close associates, even high-school classmates, are still alive; their memories, tightly edited by Miller, who brooks no sycophancy, give the story verve and spontaneity, especially in the engaging account of the Johnson City boyhood which Johnson, in life, insisted upon depicting as bleak and barren.

Johnson the Senate leader is, of course, legend on Capitol Hill. Miller adds to the lore, recreating the melodrama of Johnson's one-vote victories and telling a largely untold story of his cunning in bringing down Joe McCarthy. Barry Goldwater appears, longing for Johnson's strong leadership: "in those days at least you knew."

Humphrey is the book's star, extravagant descriptions tumbling over one another: Johnson "was like a tidal wave . . . He went through walls . . . He was a downfield brother and running fullback all the time." Lady Bird is more restrained, but still warm and pleasingly candid. "At first," she says of her husband-to-be, "I thought he was quite a repulsive young man . . . It ws just like finding yourself in the middle of a whirlwind."

Miller's witnesses are an eclectic group, known and unkown. One man, many men, Johnson is seen the same by none who knew him. Harry McPherson: "A true sophisticate." Richard Bolling: "A crude bastard." Betty Furness: "An adorable bear of a man." John B. Connally: "Cruel and kind, generous and greedy, crafty and naive." Wilbur J. Cohen: "Boccaccio, Machiavelli and John Keats."

Johnson, embittered at the failure of his own memior, The Vantage Point, died believing that "they" -- loosely meaning New York publishers and critics -- "will never let any book about me sell."

He was wrong, Doris Kearn's psychobiography, Lyndon Johnson and the American Dream, made the best-seller lists and is standard reading at universities. Lyndon, a Book-of-the-Month Club alternate, is already in demand at Washington bookstores. Johnson's own book failed for a reason: at taping sessions, he would relate an event blandly and boringly, then say, "Shutt off that damn recorder and I'll tell you what realy happened."

What "really happened" is the best part of the story of the man Miller sizes up as "without doubt one of the most complex, fascinating, difficult, colorful personages in American history." Biography, history and, at times, comic opera, Lyndon is a drought-breaking relief from the parched confessionals of recent presidential literature.

What would the subject himself say ofLyndon? Given his penchant for misnaming persons who incurred his displeasure, I suspect he would tell the press, "No, I have not read the review by my former friend, Hamilton Busby, but I understand that my wife has been deceived, my friends have betrayed me and Squirrel Miller has crucified me." Having said that, he would retire to the bedroom, switch on the light and pass the night reading his copy, laughing until the tears came. Skip a lunch or two and buy Lyndon; you'll enjoy it far more than the fall campaigns.