Children's literature R. M. Ballantyne and G. A. Henty specializing in the production of adventure fiction for boys. This inspired writers who normally catered to adult audiences to write for children, and an example is Robert Louis Stevenson's (1850–94) classic pirate story "Treasure Island" (1883). In the years after the First World War, writers such as Arthur Ransome (1884–1967) developed the adventure genre by setting the adventure in Britain rather than distant countries. Ransome began publishing in 1930 his Swallows and Amazons series of children's books about the school-holiday adventures of children, mostly in the English Lake District and the Norfolk Broads.
Swallows and Amazons series adventures in the series, the children change roles and become explorers or miners. In the novel "Winter Holiday", the children meet Dick and Dorothea Callum, siblings visiting the area. Dick and Dorothea are often referred to as "The Ds" and appear in subsequent novels. Dick considers himself a scientist, while Dorothea sees herself as a writer. Two of the books feature the Callums without the Swallows or Amazons: "Coot Club" and "The Big Six". They are set in an accurate representation of the Norfolk Broads, particularly the small village of Horning and its surrounding rivers and broads. Two other books