Fens, bogs, swamps and marine estuaries are the earth's most desirable and dependable resources, and in four stunning parts, Proulx documents the long-misunderstood role of these wetlands in saving the planet. Taking us on a fascinating journey through history, Proulx shows us the fens of 16th-century England to Canada's Hudson Bay lowlands, Russia's Great Vasyugan Mire, America's Okeefenokee National Wildlife Refuge, and the 19th-century explorers who began the destruction of the Amazon rainforest. Along the way, she writes of the diseases spawned in the wetlands - the Ague, malaria, Marsh Fever - and the surprisingly significant role of peat in industrialisation.