Atmidday, when Washingtonians are unlashed from their galley oars and allowed to wander off in search of lunch, many of the currently mighty go to The Palm restaurant. The experience should be chastening as well as nourishing.

The Palm's walls are covered with caricatures of famous faces from a few years ago. Almost all are unknown to almost everyone today. Sic transit what? Glory? Hardly. Fame? Not really. Celebrity is the perishable commodity.

That is the subject of a slender, melancholy novel on the sociology of celebrity, that renewable resource of a throwaway culture. The author is Michael Herr. The title is ''Walter Winchell,'' and if that name rings a bell, you are getting on.

Winchell was a terrible person and a grotesque social phenomenon. In the 1940s, he was at the apogee of a career that went from ripeness to putrescence with a speed satisfying because appropriate. He dealt in ephemera, and such he proved to be. But for awhile he prospered by feeding -- and by feeding, enlarging -- the nation's appetite for gossip, which is the democratic voyeurism of the masses.

He was America's most widely read journalist, serving up six columns a week to more than 1,000 newspapers, and his weekly radio broadcast was heard by more people than the 50 million who read him, one-third of America's population then. Herr captures (so well you want to take a shower) the rawness of the man who sat at Table 50 in the Stork Club on Manhattan's East 53rd St., hanging out with Hemingway and Damon Runyon and low-lifes who were products as well as producers of America's burgeoning publicity industry.

Herr calls Winchell ''the architect and the inventor of the end of private life'' and the ''endless river of facts and distractions and gossip'' with which we are inundated. This blitzkrieg of clutter, often called news, leads to survival of the briefest, because America's attention span is approximately 9.8 seconds. That was the length of the average television ''sound bite'' of candidates in the 1988 presidential campaign.

Winchell, says Herr, was ''the wizard of the American vicarious,'' and ''if passing time has obliterated him, it has also given him the status of a forgotten ancestor. If people go around today treating themselves like celebrities because not to be a celebrity is just too awful, we may have Walter Winchell to thank.''

No thanks. Do not confuse symptoms with cause. Thank -- blame -- democracy, and the Graphic Revolution and human nature.

Democracy -- equality before the law -- may be an irritant provoking an itch for distinction, even the derivative distinction of knowing the inside skinny about the ersatz-distinguished -- people who are all exterior. Perhaps affluence, too, contributes to contemporary restlessness and the sad desire to be star-struck. When urgent material wants are satisfied, celebrity becomes especially tantalizing. Magically, it can be mass-produced, yet seem scarce. And it is democratic -- available to anyone -- because it is unconnected with merit: Al Capone, one of America's first superstars, was applauded at the ballpark.

In 1961, 11 years before Winchell died in obscurity, Daniel Boorstin published ''The Image: A Guide to Pseudo-Events in America.'' A pseudo-event is something manufactured to seem significant. Celebrities are human pseudo-events.

What Boorstin calls the Graphic Revolution, from photography to television, created novel powers for making people famous, and thus made ''fame'' a problematic word. Today our overpopulated consciousness is chock-full of celebrities, people well-known for being well-known. Celebrity, says Boorstin, is a new kind of eminence, a reflection of the audience's emptiness, a receptacle into which people pour their purposelessness.

The democratic ethos, celebrating the power of the people to govern themselves, encourages derogation of heroes. Modern ''democratic'' historiography expels heroes (and hence drama) from the human drama, replacing them with ''forces'' and ''classes'' and ''the people.'' But the empty pantheon is reoccupied by celebrities, products of modern techniques for fabricating well-knownness.

Time was when people felt themselves made better by heroes who made themselves. But celebrities are made democratically, by the people, and thus have no power other than to amuse.

Boorstin notes that people with real fame enter a nation's consciousness slowly and inhabit its past. Celebrities exist only in the moment. And for a moment.

The agency that makes celebrities -- publicity -- unmakes them, depriving them of all they had: novelty. Round-the-clock media beget saturation journalism (broadly defined), which wears out subjects quicker than you can say ''Trump!'' (Who?)

''News,'' said one of Hearst's first editors, ''is anything that makes a reader say, 'Gee whiz!' '' It is impossible to exaggerate the unimportance of most things that make people say that.