An extremely rare handwritten manuscript of an unfinished novel by British author Jane Austen was sold for $1.6 million Thursday by Sotheby's auction house in London.

The unfinished draft of The Watsons is believed to be Austen's earliest surviving manuscript. It was probably written around 1804, before her first published novel, Sense and Sensibility, appeared.

The story focuses on a family of four sisters, the daughters of a sick and widowed clergyman.

The 68-page manuscript was neatly written by Austen and contains her corrections and revisions. But it is incomplete. The first 12 pages were sold by an Austen descendant during World War I to raise money for the Red Cross. Those pages are now in New York's Pierpont Morgan Library.

The manuscript, which was expected to sell for between $320,000 and $490,000, brought more than three times its estimated price.

Six of Austen's novels were published, including Pride and Prejudice. Austen died in 1817 at the age of 41.