Bridges of Madison County, Take Two : SLOW WALTZ IN CEDAR BEND, <i> By Robert James Waller (Warner Books: $16.95; 197 pp.)</i>

Robert James Waller’s “The Bridges of Madison County” has been the publishing sensation of recent years. From a quiet, unheralded, largely unreviewed start, it has gone through 46 printings, sold more than 4 million copies and seems likely to be dislodged from atop the bestseller lists (where it has sat for several months) only by Waller’s new novel, “Slow Waltz in Cedar Bend.”

The first book had an initial printing of 29,000 copies; the second, the publishers say, begins with 1.5 million copies in print, a sale to the movies already completed, a major book club main selection in hand, an audio version en route to market. Wow.

What made “The Bridges of Madison County” such a phenomenal success, it seems clear, was Waller’s skill at evoking that one tremendous, tremulous, heart-pounding, life-changing love affair that all but the flintiest in the congregation imagine is still waiting to engulf us--or once did, or almost did, or might have except for a word left unspoken, a gesture left unmade.

The question, of course, is whether Waller can summon the lightning once again. Whatever happens, it will not be for lack of trying. He has left his formula for success as intact as humanly possible without actually resorting to carbon paper.

His first hero was a photographer, a rugged loner; Waller is avocationally a professional photographer. His new hero is an economics professor, a rugged loner, at a small Iowa university; Waller has been an economics professor at a small Iowa university. Writing from what he knows and feels has given both books a useful grounding in reality before the fantasy takes over.

Waller’s first heroine was another man’s wife, of extraordinary but stifled sensuality. His new heroine is also another man’s wife, of extraordinary but stifled sensuality, although this time carrying a mysterious and obviously complicated past. Jellie Burden--a wildly inappropriate name--appears to be at least marginally less a dream-figment of the male imagination, a charge some feminists lodged against the earlier heroine.

There are other differences. The flashback form, which Waller handled with considerable deftness in “Bridges”--recreating from documents a love affair whose principals had been dead for years--has yielded to a more immediate narrative. It, too, is craftily done, as Waller cuts back and forth between professor Michael Tillman’s trek through India to find his lady, and his detailed recollections, gazing at her picture all the while, of how it all began, that brief, intense and failing struggle against the irresistible summonings of their loins and souls. Jellie has fled to India to think things through.

What remains very much the same is the characterization of the hero. Like Robert Kincaid of “Bridges” (so credible a photographer readers reportedly phoned the National Geographic in search of him), Tillman is a nonconformist, keeping an antique motorcycle in the living room of his ratty apartment and tinkering with it through the long Iowa winters. He is a dedicated teacher, fighting his students’ acceptance of a passable mediocrity and turning them on to the excitements of abstruse linkages between economics and behavior.

“Slow Waltz in Cedar Bend” is still hardly more than a novella, and its just under 200 small pages can be read twice on a Chicago-Los Angeles flight. But Waller has nevertheless extended himself. The husband in question is this time more than a stock figure, indeed a sad and subtly, if quickly drawn, personality. Minor characters, including Jellie’s parents, are a bit more than dim snapshots. And the reader has no trouble imagining that Waller may well have spent time in India and retained strong impressions of its magnitude, beauty and squalor.

Gore Vidal has predicted the early demise of the serious novel, an alarm that may first have been sounded about the same time as the beginning of the novel. Yet the huge acceptance of “The Bridges of Madison County”--fueled initially by independent booksellers and their readers, who liked the book and told others about it--has a significance that can’t just be written off as the end of culture. The age of higher technology feels as cold and impersonal as deep space, and the warmth of fiction, including tales like Waller’s, positioned well south of Marcel Proust, would appear to have a long usefulness ahead of it.

It begs the question to say that readers who liked “The Bridges of Madison County” will like “Slow Waltz in Cedar Bend,” but it is largely true. A reasonable guess is that the new work will enjoy a substantial if, compared to “Bridges,” somewhat diminished success. Waller will no longer be a novelty and a social curiosity.

What “Slow Waltz in Cedar Bend” makes clear is that Robert Waller is not an accident but a crafty and clever writer who has touched a nerve of wistful romantic longing in his audience and is not about to take his hand away.