Chronicles the travels and adventures of Captain William Lewis Herndon, who was appointed by the US Navy to lead the first American expedition into the Amazon Valley. Herndon departed Lima, Peru, on May 20, 1851, and arrived at Para, Brazil, nearly a year later, traveling 4,000 miles by foot, mule, canoe, and small boat. He cataloged the scientific and commercial observations requested by Congress, but he filed his report as a narrative, creating an intimate portrait of an exotic land before the outside world rushed in.