What is the author's style in Jubilee by Margaret Walker?

The story is divided into three sections. Each section is identified by Roman numeral and title. Section one is titled "Sis Hetta's Child - The Antebellum Years." This section contains the first eighteen chapters of the book and opens with the death of Hetta, Vyrie's mother. The chapters of this section include Vyrie's formative years and her first meeting with the free man, Randall Ware, as well as their marriage and the births of their three children. The section ends with Vyrie's failed attempt at escape and the beating she endures because of it. Section two is chapters nineteen through forty and is titled, "Mine Eyes Have Seen the Glory - The Civil War Years." These chapters include the reaction to the country at war and the deaths of the Dutton family members who fought. The majority of the slaves are taken away during this chapter and those who remain struggle to keep the family fed. The third section is titled "Forty Years in the Wilderness - Reconstruction and Reaction." The section includes chapters forty-one through fifty-eight. These chapters are focused on the lives of Vyrie, Innis and Randall Ware after the end of the Civil War. The reader learns about the difficulties of the blacks who seek only to build new lives for themselves as the country tries to recover from the devastation of the Civil War. Each chapter is also numbered and titled. Chapter titles offer clues as to what the reader can expect from each chapter. Examples of this are "Seventy-five lashes on her naked back," which indicates that a slave is beaten; "My name is Innis Brown," in which Innis is introduced; and "Bound for Alabama," in which Vyrie and her family leave Georgia. Chapters range greatly in length. For example, chapter four is only three pages in length and chapter twelve is only two pages. However, chapter two is twenty pages.