The Narrative of Arthur Gordon Pym of Nantucket
by Edgar A. Poe
Note on the text: Episodes 1 and 2 appeared in the Southern Literary Messenger in January and February of 1837. For these I have included the chapter divisions of the 1838 Harper edition in brackets. The remainder of the text retains the Harper chapters.
Pym has been called a derivative text. In two of the Episodes, highlighted text is linked to a potential source, or, in the language of this site, "Pretext."
The Preface was published in 1838. A strictly chronological reading of Pym as it was published, then, would proceed in the order: Episode 1, Episode 2, Preface, Episode 1, etc. A strictly chronological reading of Pym as it was (most probably) written puts the Preface last.