Working from a wide range of sources, including models, manufacturing records, catalogues, advertising leaflets, etc. (he was frustrated to find that most inventors and businesses did not keep records of failed inventions), Giedion traces the development of mechanization in Western history, from ancient and medieval times to the mid-20th century, with an emphasis on the 19th and 20th century. The books is arranged first thematically and then chronologically, and technologies, photography, painting, and business history are all intermingled, so that the reader can get a sense of the social and cultural context of different kinds of technologies in addition to a general sketch of their development. For instance, his section on movement includes Oresmi's 15th century diagrams of planets in motion, Marey's 19th century photographic studies of birds in flight, Muybridge's photos of men at work and Gilbreth's abstract lines of time and motion studies; as movement becomes more abstract, representations of it (Joyce, Picasso) become more fragmented and sad about the loss of human continuity. Perhaps mechanization, as linked to this rationalization of living movement, separates thought and feeling?
