For thousands of years warfare had been the business of armies of foot and horse soldiers whilst the seas and oceans were contested by the collision of navies propelled by wind, sail and oars. The industrial age of the mid-nineteenth century brought in a new era where technology would find its way into every aspect of the life of mankind. Predictably that did not exclude the business of killing. In the development of the aircraft and the submarine new, hitherto impossible dimensions were attained and their influence removed the limitations of warfare confined only to the surface of our planet. This excellent and substantial book charts the development and wartime proving of submarines and aircraft in the most detailed way, up to and including, in some detail, their operational use during the First World War. This account includes many diagrams, illustrations and photographs which are sure to captivate anyone interested in the Great War of the machines.