From 1831 to 1836 Charles Darwin, then a young man in his twenties, was the official naturalist on the Royal Navy ship HMS Beagle. The Beagle spent five years completing a survey of the coasts of South America and making a series of longitude measurements around the world. This proved to be one of the most important scientific voyages of the 19th century, for it was on this voyage that Darwin made the observations that lead, twenty years later, to his formulating the theory of evolution by means of natural selection. This book is Darwin's account of his observations on this voyage. Darwin was a master of detailed observation, and he describes the things he observed -- the plants, animals, geology, and people -- in loving detail. His accounts are always lively and full of interest. Darwin was also a master of inductive reasoning, and there are several superb examples of this in this book. Perhaps the finest is Darwin's induction of the cause of the formation of the coral atolls that dot the South Pacific and the Indian Ocean (his theory was proved correct in the 20th century). Indeed, much of the value of this book for the modern reader lies in the many examples it contains of scientific, inductive thought; a powerful method of reasoning that is as neglected today as it was in Darwin's time.