A Relic Run Amok : PETER DOYLE <i> By John Vernon</i> ; <i> (Random House: $22; 417 pp.) </i>

“Forget ‘Less is more,’ ” John Irving told a University of Iowa Writers’ Workshop class in the early 1970s. He was then writing “The World According to Garp,” with its sprawling plot and its stories within stories, and he was declaring his revolt against the slim, understated, fastidious, word-squeezing, academic novel. “More is more.”

In “Peter Doyle,” John Vernon gives us more--gives us what, at first reading, appears to be the whole 19th Century. The search for Napoleon’s penis--removed, according to legend, by a relic-seeker during the emperor’s autopsy on St. Helena in 1821--is like a zigzagging trail of gunpowder that sets off fireworks in distant times and places. Victorian London. New York just after the Civil War. Amherst, Mass., where Walt Whitman visits his poetic opposite, Emily Dickinson. Colorado Territory, where Nathan Meeker, a disciple of editor and presidential candidate Horace Greeley, founds a utopian community and is killed in a Ute Indian uprising.

Vernon seems able to write with fluency and authority--and at times with delicacy and profundity--about anything whatever. The Credit Mobilier railroad scandal. The history of Punch-and-Judy shows. The ideals of the Grahamites and Fourierites, forerunners of the dietary and communal movements of the 1960s. The etiquette of dueling. The ordeal of workers excavating the foundations of the Brooklyn Bridge in watertight caissons pumped full of compressed air. Even the folklore and customs of the Utes, from the point of view of the Indians themselves.

All this information, like tons of silt suspended in the Colorado River, is swept along in a torrent of narrative. The fun--for this is a comic novel--comes on two levels. The lower level is riotous and grim. There Joseph Bonaparte Delafolie Benton, descendant of one of the emperor’s bastard offspring, schemes to get his hands on the prized relic, which looks like a blackened twig and feels like “old twisted leather.” His chief rival is Timothy Stokes, a sponge-faced Cockney collector of “curiosities.” Benton has money and charm and a psychopath’s cunning, but Stokes has a formidable ally: Bonny, a 22-inch-tall human bloodhound he has created by alchemical processes--created without a penis, to fixate him on the missing one.

Where is it? In a pouch hung around the neck of one Peter Doyle, who regards it merely as a good-luck charm. Doyle, a dandified young man-about-Manhattan with a mysterious past, inhabits the novel’s upper level, where the humor is subtler and admits currents of sentiment. He heads west partly because of his love for Meeker’s daughter, Josie, and partly because of Whitman’s jealous attachment to him. Walt, meanwhile, has struck up a fictional (but remarkably convincing) correspondence with Emily, who entertains him in Amherst without letting him see her: She hides behind the curve of a stairway and sends down a basket of cookies on a string, along with shyly barbed words.

Vernon, whose previous novels were “LaSalle” and “Lindbergh’s Son,” reminds us time and again of the continuity of American history. There’s nothing new about yuppie financiers, wife-beating, drug addiction, farm debt, puritanical reform, real-estate scams, gender confusion or people who reinvent themselves as they go along. This may indeed be, as the publisher’s blurbist says, “a virtuoso meditation on the progress of myth (and) the myth of progress.” At the least, “Peter Doyle” is a terrific read.

It’s also substantial enough to invite the killer question: Is this a major novel, a lasting contribution to American literature? That we can fairly confidently answer “no” demands an explanation.

Vernon can’t be faulted for writing a two-level story. The Victorians he’s imitating, such as Dickens, did the same thing; so did Shakespeare. But in “Peter Doyle,” the levels remain separate--even grow further apart--when the plot seems to require them to converge.

The expected confrontation between Doyle and his pursuers can’t happen because, by then, Doyle has delivered a harrowing confession to Josie in the Indian tent where they are held hostage, and the Utes themselves, even before the cavalry arrives, are seen moving “in slow motion, as if rehearsing defeat . . . becoming statues on courthouse lawns, looking off toward the distance with grim faces etched, and pigeons on their shoulders.” The world of slapstick puppets and murderous homunculi has to unravel by itself.

This suggests that, with all due respect for Irving’s view, the whole can be smaller than even the most brilliant parts. A novelist shouldn’t put everything in just because he’s able to.

The hunt for a piece of Napoleon is an attention-grabbing premise for this book, but it’s not sturdy enough to be a spine. Then there’s Vernon’s attitude, which is sane and reasonable throughout; he describes the follies and the horrors of the 19th Century with the same benign detachment. We miss the urgency, even the venom, of Dickens’ and Twain’s humor.

It sounds strange to accuse the author of so massive and energetic a work as “Peter Doyle” of not caring enough, but that may be it. More or less.