The Last Verse.(blues music)

In a small white house on a quiet country road in the foothills of northeastern Georgia--the end of Appalachia or the beginning, depending on your point of view--there lived an old blues singer named Cora Mae (Sweet Petunia) Bryant. Rumor had it that she could be difficult. Bryant had been known to slam her door on uninvited visitors, to demand a few "dead Presidents" for an interview, and to beat her manager with a purse for getting her onstage too late. Her nickname was borrowed rather than earned. It came from a song that her father, the blues guitarist Curley Weaver, wrote in 1928. Cora Mae was born two years earlier, but the lyrics were clearly about someone else: "I've got a gal, she's long and tall, every time she do the shimmie I holler, Hot Dog!"

When Lance Ledbetter and Art Rosenbaum arrived at Bryant's house one morning in December, the place looked welcoming enough. There were electric candles on the windowsills and candy canes on the lawn. The porch was hung with pots of plastic daffodils, and metallic letters spelling "Merry Christmas" had been strung above the door. A closer look, though, revealed some cause for concern. The old piano on the porch had a serrated knife laid across its keys. The Bible perched on the railing was open to Hosea 4-5: "They shall eat and not have enough. They shall commit whoredom, and shall not increase. . . . They shall go with their flocks and with their herds to seek the Lord; but they shall not find Him."

Ledbetter looked around, a little nervously. He wasn't cut out for field work. Moonfaced and bespectacled, with brown hair slicked back and parted, he looked like a character from "Little Orphan Annie"--the millionaire's son, out for a spin in his Studebaker. He was thirty-one years old and owned a small record label in Atlanta called Dust-to-Digital. He had an encyclopedic knowledge of American blues, country, and folk music, and had released what many consider the greatest gospel compilation ever made: a six-CD set called "Goodbye, Babylon." But he wasn't used to working with live musicians: most of his artists had been dead for decades.

He glanced over at Rosenbaum, who had plopped into a wicker chair on the porch, completely at ease. A faded gray vest hung over his belly and an old baseball cap was pulled down over his pale, dumpling features--his white hair stuck up around it as if charged with static. A minute ago, he'd knocked on the door and been told that Sweet Petunia was indisposed--she was still digesting her breakfast, her son David said. But Rosenbaum was happy to wait outside. A folklorist, a painter, and a professor of art at the University of Georgia, he had spent fifty of his sixty-nine years travelling around the South and the Midwest, recording folk musicians. He'd taped one old singer through a screen door--she wouldn't let him into her house--and another shortly before she was sent to prison, at the age of eighty-two, for dealing marijuana. "That jury'll never convict me," she reportedly said. "I've sold moonshine to half of 'em and fucked the rest."

Rosenbaum was a folk revivalist of the old school. He believed that traditional ballads, blues, spirituals, and fiddle tunes are among the glories of American culture, and he wanted to help preserve and disseminate them. Ledbetter, forty years younger, was less interested in preservation than in inspiration: the songs on "Goodbye, Babylon" had influenced artists as diverse as Bob Dylan and Arcade Fire. The best he could do for folk music, Ledbetter seemed to feel, was to research, remaster, and repackage it as beautifully as possible--to make the old songs seem new again.

Earlier that fall, Ledbetter's label had released "Art of Field Recording: Volume I," a four-CD retrospective of Rosenbaum's work. It contained everything from ring shouts and murder ballads to a song about twenty frogs going to school. It was full of throaty voices and clanging banjos and the incidental music of daily life--babies crying, bar glasses clinking, cicadas on a summer night. A critic at the Times had called it "a gold mine, an ark . . . spooky and blindingly beautiful." But now Rosenbaum and Ledbetter were gathering songs for the second volume, and wondering what they'd find. Fifty years after Rosenbaum's first recordings, what was left of folk music?

Bryant liked to call her house a museum of the blues. When her son let Rosenbaum and Ledbetter in, it took a while for their eyes to adjust. A dingy light seeped in around the shutters, and the doorframes were hung with rumpled sheets. Most of the "exhibits" on the walls were secondhand stuff: yellowed newspaper clippings, blurred copies of black-and-white photographs, candy-colored cartoons of legendary bluesmen by R. Crumb. In the back, next to the kitchen, Bryant sat in a room that smelled of honey and funk, a shrivelled daddy longlegs hanging from the ceiling above her. Her face was still formidable--sharp bones, taut brown skin, steel-gray hair combed straight up. But her left side had been paralyzed by a stroke, and her amber eyes had gone vague with age and inactivity.