Find more images by Fritz Kahn in the Gallery of Machines.
For thousands of years human beings have used metaphors as ways of understanding the body. We talk about our 'ear drums', or our 'mind's eye'. When we are in love we say our hearts are 'bursting' or 'broken'. When we are nervous we say we have 'butterflies in our stomach'. When we are impatient we have 'itchy feet'. These familiar images help to explain the unfamiliar and to comprehend the complexity of our bodies.
The image above, by the artist Fritz Kahn, shows the nervous system as a complex electronic signalling system, complete with buttons, charts and busy workers. Fritz Kahn's books and illustrations explored the inner machinery of the human body, using metaphors of modern industrial life. Kahn turned the brain into a complex factory with light projectors, conveyor belts, secretaries and cinema screens; he showed the journeys of blood cells as locomotives encircling the globe; and he compared bones to modern building materials such as reinforced concrete.
Kahn was writing in the 1920s, a period in of great industrial and technological change. The manufacturing industries were achieving incredibly high levels of efficiency thanks to the latest methods of production: factory assembly lines, for example, required only a simple and relatively unskilled input from factory workers. For these workers the body was like a piece of clockwork, its calculated movements acting solely as a functional cog in the social machine.
Technological advancements were bringing many other transformations to the world. A new nature was being constructed. Man could now fly, speak to people on the other side of the world, capture voices and faces that, once preserved, would later seem to be able to bring back the dead. It was an era of great excitement in which people believed that technology had the potential to create a world free from poverty and hardship - a kind of utopia in which machines would protect us from nature's moods, and would provide enough food and protection for all. In fact we were then, and are now, far from fulfilling that dream - but many believe that it is still a possibility for the future.