FOR 20 YEARS after 1940, A.J. Liebling was a legendary figure for a widening circle of writers, journalists and media freaks. In the words of his biographer, Liebling "invented modern press criticism" and did it in a unique style during a crucial period. Before him, written views of the press tended to be either delirious self-worship by publishers and their acolytes or bitter dissections by social critics like Upton Sinclair and George Seldes. bLiebling came upon the scene during the anti-communist hysteria, always a siren song for American publishers, and he continued monitoring sloppiness and bias in the years when manipulation of news was being fashioned into its present high-powered profession. His distinctive voice during this period was not in thundering novels of protest like Sinclair's The Brass Check or in four-page newsletters mailed to the faithful, like Seldes' In Fact . Liebling's ridicule of self-serving publishers and simple-minded reporters appeared in the fashionable pages of The New Yorker , surrounded by cool inducements to buy $1,800 watches, social criticism the elite would see and in a setting publishers would respect or envy.

For several years starting in the 1970s, a new generation of journalists sensitive to imperfections in their trade met annually under the rubric of the dead Liebling, though many had never read him.

This first biography of Liebling, Wayward Reporter by Raymond Sokolov, will introduce the man to this generation and surprise most of his old admirers. It is a powerfully told tragic story, though for a subject who "invented modern press criticism" the book's emphasis is curiously skewed.

Liebling was born in New York in 1904 into a hosehold with maids and a butler named Louis. His father, a newly rich furrier, named his son not Abraham but its Wasp transliteration, Abbott, which the boy understandably hated and who, at Dartmouth, dropped it in favor of the diminutive, Joe, of his middle name.

Abbott was a fat and clumsy Jewish kid with thick eyeglasses who hung out with bulky Irish athletes and lusted after good-looking Irish girls. After Dartmouth, he spent several years as a reporter for The Providence Journal , the New York World , and the World-Telegram and finally landed at The New Yorker . The magazine was perfect for him, conducted by intelligent editors who were tolerant of eccentricities, gently imposed stringent standards, and let good people have their heads.

Liebling spent much of his writing life celebrating the non-elite -- soldiers and sailors at war, diligent hustlers, colorful scoundrels, boxers and journalists. "He could wrap himself up in these roles and ignore the fact that he was obese, Jewish, tragically married, ofter depressed."

In the flesh, Liebling was most noticeable as a gourmand. He ate shellfish by the dozen (in the 8th grade he had already contracted typhoid fever from polluted oysters). I worked for the Providence Journal a generation after Liebling did but even at that late date he dropped into the Journal city room during his visits to a hospitalized wife. He would dazzle old friends by downing a six-course meal with two wines at the best Italian restaurant in Providence and without a minutes's rest would order a full repeat.

He was the envy of most other writers, a sparkling essayist with a baroque style that bordered on the bizarre. It worked. He wrote powerfully of war and soldiers, joyously punctured and sacrosanct publishing fraternity, and described middleweight boxing matches with a dedicated and colorful precision usually reserved in slick magazines for designer gowns and Jackson Pollock canvasses.

But his biographer also describes a different Liebling, given to depressions and prolonging hopeless marriages. His first wife, Ann McGinn, was a schizophrenic in and out of hospitals. His second wife, Lucile Hille Barr Spectorsky, with a model's love for expensive clothes, effectively ended their marriage as they stood in readiness to depart on a long-planned trip to his beloved France. She pointed to her portion of the packed bags and told the hotel bellman, "Don't take those. They stay here." Liebling went alone, overweight (250 pounds), sick not only with his broken love life but with ailing kidneys, liver and heart. Even his last marriage to another New Yorker writer, Jean Stafford, a generally happy relationship, grew increasingly distant as Liebling ate and drank himself to death.

After 1951 Liebling tired of writing about the press, but he continued to do it in the "Wayward Press" department of The New Yorker . Still the fat kid hanging out with jocks, he returned to his love of boxing. In 1959 he tired of magazine writing and did three books, Normandy Revisited, The Earl of Louisiana , and Between Meals . Though they had devoted readers, none of his books ever sold well.

Toward the end he suffered from deep depression, terrible pain from gout, diverticulitis, parathphoid and, like Hemingway, the more deadly affliction of an unshakable writer's block. He died December 28, 1963, his last comatose words in unintelligible French.

Raymond Sokolov has created a moving and powerful biography, full of striking detail and extended analysis. He has an unfailing eye for quotations, usually the curse of biographies of writers. In this work they never pall, and they bring to life Leibling's rococo and joyous style.

Sokolov compares Liebling to Defoe, Hazlitt and William Cobbett, seeing him as a "writer of lasting significance" who was "slumming in journalism."

Unfortunately, Sokolov's interest in psycholiterary analysis sometimes sounds like an Eng Lit thesis on "Samsom Agonistes." The author's contempt for reporting, as distinct from writing, weakens his perspective on a subject who was a distinguished reporter as well as a literate writer. Liebling is not likely to be "a writer of lasting significance" in American literature. He was a talented essayist and splendid journalist, but except for collectors of the literature of boxing, he has lasted as a literate critic of an increasingly important social institution.

Though the author's view of Liebling the litterateur too often obscures the more valid judgment of Liebling as an estraordinary reporter and critic, this book is a poignant and powerful portrait of a brilliant and tragic journalist of the middle years of a tragic century.