In 1648, Europe was essentially a medieval society. By 1815, it was the powerhouse of the modern world. In exuberant prose, Tim Blanning investigates 'the very hinge of European history' (The New York Times) between the end of the Thirty Y ears' War and the Battle of Waterloo that witnessed five of the modern world's great revolutions: scientific, industrial, American, French, and romantic. Bla…