Alexander von Humboldt, who died in 1859 at the age of eighty-nine, was not only the most famous scientist of his day but also one of the world's best-known figures. He met often with political leaders, from Thomas Jefferson in the new United States to King Friedrich Wilhelm III of Prussia, and he expanded outwards from his bases in Paris and Berlin to pursue various scientific expeditions, particularly across Latin America in 1800 and Russia in 1829, that changed our knowledge of the physical world. ('We have little knowledge of the Spanish colonies', Jefferson told Humboldt when they met in 1804, 'but through you.') Humboldt's 'adventures' are now celebrated in a new biography by Andrea Wulf, a freelance journalist who is the author of two books on gardening. The Invention of Nature is a well-written volume, with a nice eye for comic anecdotes, and it is certain to help restore Humboldt's claims on the public attention.