From wikipedia:

Eclipse is the third novel in the Twilight Saga by Stephenie Meyer. It continues the story of 18-year-old Bella Swan and her vampire love, Edward Cullen. Eclipse is preceded by New Moon and followed by Breaking Dawn. The book was released on August 7, 2007 with an initial print run of one million copies,[1] and sold more than 150,000 copies in the first 24 hours alone.[2]

The chapters are helpfully numbered 1-27 and you can click the image for a better look.

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