This book deals with the period when iron became the dominant 'high-technology' material, increasingly taking over from timber and masonry. It was necessary for the engines and machines of the new industries, but equally vital for the vast civil engineering works which supported this industrialisation. It was these works - mills, warehouses, dockyards, and above all bridges - which so impressed the public in the early 19th century. The papers selected here trace the evolving structural uses of cast and wrought iron in frames and roofs for buildings, and look in particular at the development of bridge design and construction, in America, France, and Russia, as well as in Britain. They cover the processes of design and testing, and at the same time throw much light on the attitudes and careers of the engineers themselves.