Published together in 1846 for a British readership, these reports of two westward expeditions shed light on the challenges of exploration in nineteenth-century North America. Led by the army officer and future presidential candidate John Charles Frémont (1813-90), who became known as 'the Pathfinder', the first expedition ranged west of the Missouri River, while the second pushed beyond the Rocky Mountains, north to Fort Vancouver and then south into Mexican-held California. Frémont's detailed accounts are accessible to the non-specialist: this edition omits 'only the portions which are altogether astronomical, scientific, and philosophical, and, therefore, not adapted for general utility'. When originally published separately in 1843 and 1845, the narratives enthused a great many Americans, encouraging them to migrate west by providing stirring inspiration, valuable maps and practical information. Frémont's words and deeds remain of interest in the debate surrounding the 'manifest destiny' of the United States.