From its initial publication, the unconventional structure of The Grapes of Wrath has been both attacked and misunderstood by a great number of readers. Steinbeck's method of inserting chapters of general information or commentary between straightforward narrative chapters frustrates many readers who consider them distracting, an interruption in the "real" story of the Joad family.
These intercalary chapters, as they were termed by critic Peter Lisca, serve a distinct purpose in commenting on and expanding the events of the narrative proper. Sixteen intercalary chapters are included in the book, accounting for approximately 100 pages, or one-sixth of the text. Although the Joad characters do not appear in any of these intercalary chapters, many of the incidents found in these chapters foreshadow similar situations experienced by the Joads. Some, written in a variety of literary styles, provide a generalized, dramatic overview of the central social conditions affecting the main characters, while others provide historical information and direct commentary on book's social and political background.
