The birth of the skyscraper coincided with several technological developments and social conditions: the invention of the elevator (1853), the invention of electric light (1879), the invention of the telephone (long distance after 1884), and the Chicago fire of 1871. A group of progressive clients, innovative architects, and a building boom also contributed to the intense development of tall buildings in Chicago as the century drew to a close.

HH Richardson's Marshall Field Wholesale Store (1885-87) made a stunning impression in post-fire Chicago. It marked the end of a "noble line" of urban buildings which preceded the true skyscrapers. The Home Insurance Building or the Second Leiter Building (1888-91) in Chicago by William Le Baron Jenney are both considered the first true skyscraper, which means that the steel frame carries the building's load and the wall simply hangs from the frame (hence the term "curtain wall"). The new expressive possibilities of the structural system are obvious when Jenney's designs are compared to buildings like the Monadnock of 1884-92, by Burnham and Root, whose bearing walls are two metres thick at the base. At precisely the same time, however, Burnham and Root were designing buildings like the Reliance Building, 1889-95, a superb example of the new type.

A number of technical advances were developed by the skyscraper architects. They added salt to mortar and insulated concrete with straw in order to build through Chicago's cold winters. Root's famous floating raft foundation was intended to stabilize Chicago's weak soil. The "Chicago window" was made possible through the development of the cellular facade. Since skyscraper construction meant that walls acted simply as sheathing, ground storey windows could also be larger than before and serve as advertising for the new businesses which commissioned buildings in the "commercial style."

Louis Sullivan was the most famous architect associated with the development of the skyscraper. He set out his tripartite formula in an article of 1896, "The Tall Office Building Artistically Considered." Although Sullivan was not the first to say it, we associate his work with the well-known dictum: form follows function. Our examples of his work are the Wainwright Building, St. Louis, designed in 1890-91 and the Auditorium Building, Chicago, of 1886-89.

The next important generation of skyscrapers (and skyscraper architects) were constructed in New York, rather than Chicago, after 1900. The NYC towers, however, did not have the same frank expression of structure as the Chicago buildings, but rather were clad in classical and gothic (historicist) detailing. Our illustration is the Woolworth Building, by Cass Gilbert, 1911-13.

Prof. Adams provides these slides immediately following each lecture as a courtesy to students for study purposes only. She takes no responsibility for their arrangement on this page or for any unintended use of the images.





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