There are in The Grapes of Wrath sixteen interchapters making up almost one sixth of the novel. These interchapters have two main functions. First, by presenting the social background the most of them (1, 3, 5, 7, 9, 11, 14, 17. 19, 23, and 29 chapter) serve to amplify the pattern of action created by The Joad family. Second, by providing such historical information as the development of land ownership in California, the consequent development of migrant labor, and certain economic aspects of the social lag some of them (19, 21, and 25 chapter) serve to present the philosophy or social message to which the current situation gives rise. Like the structure of the philosophical passages in interchapters, the chapters" texture have its roots in the Old Testament. This Biblical texture is supported by a continuum of symbols and symbolic actions. The most pervasive symbolism is that of grapes. Still another important Biblical symbol is Jim Casy (Jesus Christ). As the Israelites received the new Law in their exodus, so the migrants develop the new laws. The families learned what rights must be observed. Through this supporting Biblical texture and context there are interwoven two opposing themes which make up the book"s plot. One of these, negative one, concerns itself with the increasingly straitened circumstances of the Joads. This negative or downward movement is balanced by the positive or upward movement. Although the primitive family unit is breaking up, the fragments are going to make up a large group. The climax is prepared for by the last interchapter with which the novel is brought full circle. The rain continues to fall; the truck and household goods must be abandoned; the little mud levee collapsed; Rosashan"s baby is born dead; the boxcar must be abandoned; they take to the highway in search of food and find instead a starving man. Then the miracle happens. As Rose of Sharon offers her breast to the old man, the novel"s two counterthemes are brought together in a symbolic paradox. Out of her own need she gives life; out of the profoundest depth of despair comes the greatest assertion of faith.