In the spring of 1857, one of John Hill Wheeler's slaves slipped away from his North Carolina plantation and made her way north to New Jersey. There she promptly picked up a quill pen and began to write a novel, combining the story of her own life with elements of the many sentimental sagas she had evidently borrowed from Mr. Wheeler's shelf. This is the origin of a 300-page manuscript called "The Bondswoman's Narrative," according to its new owner, Henry Louis Gates Jr., the chairman of the African-American studies department at Harvard University. He says that the manuscript, unpublished and unnoticed for more than 140 years, is the earliest known novel by a female African- American slave and probably the earliest known novel by a black woman anywhere. If so, it is one of only a handful of novels by African- American slaves. Professor Gates was the only bidder for the manuscript at an auction at the Swann Galleries in New York this year, and he acquired it for less than $10,000. Two well-known experts on detecting literary forgeries, Kenneth Rendell and Joe Nickell, have verified its authenticity after an extensive investigation, assessing its contemporary historical references and the age of its ink and paper.

The novel, signed by Hannah Crafts, is a woman's melodramatic account of her life as a house slave to a number of owners and then as a teacher in the North. In one episode, the narrator accidentally gives her owner's wife a cosmetic powder that somehow turns her face black. The humiliated wife later punishes the narrator for gossiping about the incident by trying to force her to marry a field hand whom she scorns as beneath her. Horrified at the prospect, she flees to New Jersey by taking advantage of her light skin and disguising herself as a white boy. Replete with the heavy-handed moralizing and preposterous coincidences characteristic of the popular women's fiction of the time, the unedited novel is unlikely to attain the status of a literary masterpiece. But its existence suggests that some slaves managed to attain a far greater degree of literacy and literary sophistication than many historians have supposed. Its author clearly had an extensive vocabulary and a deep familiarity with contemporary literary genres even before gaining her freedom, although her spelling and punctuation were spotty.

Nellie Y. McKay, a professor of African-American literature at the University of Wisconsin, said that 10 years ago, most scholars assumed that only a handful of slaves had overcome the obstacles to their education and then gone on to write novels, and that those few who did were already known. "Now, who knows how many there were?" she said. It is impossible to know how many of the novel's details are autobiographical, but the portrait of a slave's life nonetheless provides a window into the psychology and perspective of a slave woman. David Brion Davis, a professor at Yale and a historian of slavery, said, "We have relatively few authentic slave narratives, and certainly a novel written by a black woman and former slave is almost sensational." If Professor Gates is correct, "The Bondswoman's Narrative" may be unique as a surviving handwritten manuscript of a book by an escaped slave, providing singularly direct access to its author's thoughts and feelings. Almost all known slave narratives, including Frederick Douglass's famous autobiography, survived only in printed form, raising questions about the amount of alteration by editors and amanuenses.

Details of the novel's depiction of slave life on a plantation are revealing. Its narrator discusses the sexual dynamics among owners, their wives and their female slaves; the complicated intimacy between female slaves and their owners' wives; and the revulsion of house slaves toward slaves who work in the field. "The author is a snob, she is very much an ancestor of the black bourgeoisie," Professor Gates said in a telephone interview. "She says at one point that one of the most heinous aspects of slavery is that it affects all slaves in the same way, regardless of their morals and manners and sophistication."

Professor Gates was unable to trace a specific woman named Hannah Crafts. But unlike most entirely fictional works or counterfeit slave narratives, many of the names of characters in the book belong to real people, including the narrator's final owner, John Hill Wheeler. In fact, the author apparently debated naming him, omitting the middle letters of his last name for most of the text and then going back to fill them in. Mr. Wheeler's identity proved a crucial clue to authentication. Mr. Wheeler left a diary of his life describing his plantation as well as his stints as a government official in Washington and as a minister to Nicaragua. "The Bondswoman's Narrative" contains the same intimate details as his diary, such as the timing of a boat trip from Washington to North Carolina and his dismissal from a government job. Some of the details also help date the manuscript. In "The Bondswoman's Narrative," Mr. Wheeler's wife laments the recent escape of a slave named Jane. In 1855, Mr. Wheeler's slave Jane Johnson ran away with help from abolitionists and became the subject of a high- profile court case. Mr. Wheeler's diary and the manuscript also use the same words to describe an equestrian statue of Andrew Jackson in Washington that was completed in 1853. But the novel contains no references to the Civil War, suggesting it was written before 1861.

Professor Gates suggests that one reason the author may not have published the novel is that publishing before the war would have opened the possibility of her arrest as a fugitive slave, and the market for slave narratives disappeared after the war. The manuscript later turned up in the hands of a New Jersey book dealer. In 1948, Dorothy Porter Wesley, a librarian at Howard University, acquired it on the hunch that its author was a gifted African-American slave. White authors, Ms. Porter Wesley later wrote in a letter about the text, invariably introduced black characters with heavy-handed references to their race but assumed that characters were white by default. But the author of "The Bondswoman's Narrative" often introduced black characters without reference to their race. "There is no doubt that she was a Negro because her approach to other Negroes is that they are people first of all," Ms. Porter Wesley wrote.

When Professor Gates sought a publisher in April, executives at AOL Time Warner's books division, Warner Books, consulted authentication experts. Mr. Nickell wrote an exhaustive 24-page report analyzing the style of handwriting, the period vocabulary, the brand and manufacturing defects of the paper, the content of the ink, the form of eraser used, the use of sewing materials in an amateur binding and dated historical references in the text. He concluded it could only have been written between 1853 and 1860, probably by a self-educated woman. "The Bondswoman's Narrative" is Professor Gates's second addition to the small collection of novels by 19th-century African-American women. In 1982, as an assistant professor, he authenticated and publicized the authorship of "Our Nig," written by the free African-American Harriet E. Wilson and originally published in 1859. There are two known earlier novels by African- American men, "Clotel," written by William Wells Brown and published in 1853, and "The Garies and Their Friends," written by Frank J. Webb and published in 1857. Warner Books plans to publish "The Bondswoman's Narrative" next April, as its most prominent title of that season. Jamie Raab, the publisher, said the company planned to leave the many misspellings intact for the sake of authenticity. Professor Gates sold the rights to publish the book to Warner for an undisclosed advance and royalties. He said he planned to donate the manuscript to a library.