The atlas of 1816 was littered with blanks. Where was the North Pole? Was there a North-West Passage? What lay at the heart of Africa? Did Antarctica exist? In his quest to find the answers to these questions John Barrow, Second Secretary to the Admiralty, launched the most ambitious programme of exploration the world had ever seen. 'This is travel history of the best kind: entertaining, informed and opinionated.' Sunday Times 'Get hold of this book and read it.' Barry Unsworth, Sunday Telegraph