Blum (formerly History/Princeton; the scholarly The End of the World Order in Rural Europe, etc.--not reviewed) offers a detailed, if pedestrian, analysis of a remarkable decade. The 1840's were, Blum says, ``the most amazing epoch the world has yet seen''--because of the geniuses of thought and technology who then came of age. The author devotes the first half of his study to some of these figures. He highlights the pioneers of the railroad, telegraph, and penny-post, among other innovations, arguing that they created a communications revolution that changed the lives of ordinary people and allowed a new kind of society to develop. Blum also details the work of social reformers like Shaftesbury and of radicals like Marx and Proudhon. He outlines a stimulating--though hardly original--critique of the Romantic Movement, showing it as leading to the realism of a Courbet and a Dickins, as well as to nationalism. In the worlds of science and learning, Blum introduces us to giants like Humboldt, Helmholtz, Faraday, and Darwin, plus leaders in modern medicine, the social sciences, and economics. The author then looks at the political changes that took place in the five great European nations: Great Britain, France, Austria, Prussia, and Russia. Here, again, he concentrates on individuals, making them come alive through his use of humor and anecdote. Blum is no friend of the ancien rÇgime and, at times, he's overly keen to apply a Marxist critique--e.g., in his contempt for the religious motivations of early social reformers and in his reliance on the theme of the rising middle class (when has a middle class not been rising?). Moreover, he passes mechanically from one subject to the next--but, by book's end, readers have been treated to a mass of interesting information and introduced to an assembly of outstanding personages. Thought-provoking, if dry, historical fare for the intelligent nonexpert.