William George Armstrong was one of the leading and most successful of Great Britain's nineteenth century engineers. At Elswick he began a career in mechanical and civil engineering, moving into armaments, and then on to naval and, at Walker, mercantile shipbuilding. In the later decades of the Victorian age his company was the only British firm comparable in size and range to Krupp of Essen, and by the end of his life Armstrong Whitworth was probably the largest industrial concern in Britain. Armstrong possessed exceptional powers for concentrating on practical problems, an invaluable asset which he is said to have once summed up in the homely words: `Perseverance usually pays.' It brought him a distinguished reputation, high honours and great wealth. The last was used in large part to build a revolutionary house and estate, Cragside, set in magnificent gardens near Rothbury, in his native Northumberland. Cragside was the first house in the world to be powered by hydroelectricity. It is now part of the National Trust. To contemporaries his long career was a wonderful story of success. Even now his achievement seems exceptional, but whether it was good now looks much less obvious. Today we are disturbed by contrasts between the peace and splendours of Cragside and the often blighted lives of his workers and their families in the drab terraced rows which once covered the slopes above Scotswood Road. Above all we are troubled by what, even during his lifetime, and stillmore shortly afterwards, resulted from the labours of this designer and manufacturer of weapons of war. This book explores these issues in the life of a fascinating but puzzling man.