PAUL WARDE is a Reader in Early Modern History at the University of East Anglia. Previous works include Economy, Ecology and State Formation in Early Modern Germany (2006) and Energy Consumption in England and Wales 1560-2000 (2007). He was the recipient of a Philip Leverhulme Prize in 2008. SVERKER SÖRLIN is Professor of Environmental History in the Division of History of Science and Technology at the Royal Institute of Technology, Stockholm. Among his books are Sustainability – the Challenge (1998) and Narrating the Arctic (2002, with M.T.Bravo). He won the August [for Strindberg] Prize for his two volume History of European Ideas 1492-1918 (2004).