Abstract: The Lewis and Clark expedition was commissioned in 1804 by Thomas Jefferson and lasted twenty-eight months. Meriwether Lewis and William Clark began in St. Louis and navigated up the Missouri River, through the prairies, enduring a winter with the Mandan Indians in North Dakota. They reached the summit of the Rocky Mountains and then followed the Columbia River to the Pacific Ocean. Trained in natural history and in methods of collecting plant and animal samples, Lewis and Clark meticulously recorded the conditions of the rivers, prairies, forests, mountains, and wildlife of pre-industrial America. This book, written by a botanist and naturalist, re-creates Lewis and Clark's journey. By retracing their steps, the book outlines what this western landscape looked like and how much it has been changed by modern civilization and technology.

Keywords: Lewis, Clark, expedition, Jefferson, Mandan Indians, natural history, pre-industrial America, environment, American West