WHEN he was in his mid-20s and working for a company as a boilermaker, Thurnell Alston, a black man in deep rural Georgia, performed his first act of defiance. The year was 1963."The white water fountain was refrigerated, electric, the water pure and cold. The black water fountain beside it offered tap water simply piped in from outside. It was as if the blacks were horses, to be watered from a bucket," he says. Although terribly hot and thirsty, Alston refused to drink the water. That's how the civil-rights movement began for him and, in a sense, for the black inhabitants of McIntosh County, Ga. The seeds of dissatisfaction with the status quo of black-white relations were planted for Alston at that moment. The fruit would come to maturity in 1978, when he was elected county commissioner. Melissa Fay Greene's wonderful, factual account, "Praying for Sheetrock," is an engrossing history of civil rights in a microcosm, a "chronicle of large and important things happening in a very little place," she says in an author's note. The story and dialogue are so vivid and descriptive, the book could be mistaken for a novel. But it's not. This true story of McIntosh County reminds the reader that in 1971 "the epic of the civil rights movement was still a fabulous tale about distant places to the black people of McIntosh." As one man says, "If a black person got out of control in McIntosh County, he simply disappeared. We used to say they took a swim across the river wearing too much chain." For decades, a white man, Sheriff Tom Poppell, ruled that little place. He became Alston's antagonist. One of the last of the old-time political bosses in Georgia, Poppell knew everybody and had a hand - or two - in everything that went on in the county. He even had a cadre of black spies, nicknamed "the little deputies," who kept him informed about the goings-on in their community. When it behooved him, he acted the benevolent despot, making sure poor blacks - and they were all poor - got shoes or a turkey for Christmas. But every act of decency had the same rationale - to guarantee the blacks' indebtedness to him. And no one got elected to any office without his approval. Alston was only one of the heroes who helped wake the "sleeping giant" of the black voting bloc and rally it to support him and contradict what Poppell wanted. The young white lawyers of the Georgia legal services program - the first white friends in Alston's life - laid the legal foundation for Alston's win. They helped three black plaintiffs - Alston among them - sue the county. The McIntosh County Board of Education had been appointed by a grand jury that was not representative of the population. That lawsuit was one more push, one that bolstered the courage of the black community, courage sorely needed to fight such an entrenched and often dangerous white-power structure. Greene makes the whole story so suspenseful, so full of the human voices and stories and feelings, that you are suddenly there, where "the water tasted like cold stones and the air was clean and piney." You learn how these people lived and what their houses looked like, inside and out. Greene lets a good number of them speak in their own words, and the weight of those words and their cadence reverberate in your mind long after you close the book. After power is wrested from him, Sheriff Poppell dies. Alston suffers a personal tragedy and develops grievous faults of his own. But that doesn't ruin his story - it just serves to remind us of the fallibility of all, even the heroes of the civil-rights movement. Greene has only recounted what's history, what "is at this moment being transformed and suffused with meaning, stitched into the quilt of the country's age-old oral history, the stories reaching back into slave times." But she has done it so skillfully that you don't want the story to end. I can't say enough good things about this book, and I eagerly await her next.