The most celebrated products of the first Chicago school of architecture, a series of skyscrapers constructed between the early 1880s and the early 1890s, are not only monuments signifying the emergence of the modern style; they are also monuments to the institutions that powered the incredible economic growth of the United States in the nineteenth century: financial exchanges, banks, railways, insurance companies, and department stores. However, in modernist architectural histories the association between the form of these buildings and their economic function was not much discussed. By the 1940s they came to signify the spontaneous appearance of a modern aesthetic removed from the influence of European history and taste, unconsciously derived from new construction technologies.1