When the Beagle sailed out of Devonport on 27 December 1831, Charles Darwin was twenty-two and setting off on the voyage of a lifetime. It was to last five years and transform him from an amiable and somewhat aimless young man into a scientific celebrity. Even more vitally, it was to set in motion the intellectual currents that culminated in the arrival of The Origin of Species in Victorian drawing-rooms in 1859. His journal is vivid and immediate, showing us a naturalist making patient observations, above all in geology. As well as a profusion of natural history detail, it records many other things that caught Darwin's eye, from civil war in Argentina to the new colonial settlements of Australia.