"The Pioneer Boys of the Yellowstone; or, Lost in the Land of Wonders" by Harrison Adams is a historical fiction novel written in the early 20th century. The narrative follows two young cousins, Dick and Roger Armstrong, who join the Lewis and Clark expedition in the early 1800s as they embark on an adventurous quest in the wilderness. The story delves into themes of exploration, courage, and the challenges faced by early pioneers as they encounter various Indian tribes and the untamed landscape of the American West. At the start of the story, the young explorers are preparing to spend the winter near the Mandan Indian village while being part of Captain Lewis and Captain Clark's expedition. They reflect on their homes far away and the potential dangers of venturing further into the wilderness, especially after witnessing a group of unknown Indians passing below them. Their curiosity and adventurous spirit lead them to explore the surrounding area, where they unexpectedly encounter a grizzly bear, and together they face the challenges of the wild. The opening portion sets up their devoted friendship, their determination to help their families back home, and the sense of wonder and danger that permeates their journey into the Yellowstone region. (This is an automatically generated summary.)