Monadnock Building

View depicting how the base expands to accommodate the weight of the bearing wall, close vertical side view, depicting the depth of the windows and the curve of the wall above; From 1880 Burnham & Root emerged as the principal designers of the new ten-storey skyscraper office buildings. In some two dozen subsequent structures in the city, the firm perfected 'raft' foundations to support tall buildings on the muddy Chicago soil, iron (and eventually steel) skeletal frames to lighten and expedite their construction, and a frank, unfussy treatment of façades in red brick, terracotta and sandstone to express this new technological creation. Burnham & Root designed the Monadnock Building at the south-west corner of Dearborn and Jackson Streets, with a brick exterior ornamented only by the elegant batter of its walls and cavetto cornice. When it was completed in 1892, the Monadnock was the world's largest office building. The northern half of the Monadnock represents the last Chicago skyscraper built using load-bearing wall construction; in order for the structure to support its own weight, the walls at the base of the structure are six feet (1.83 meters) thick. The building was so heavy that it sank into the ground after it was built, requiring steps to be installed at the entrances. Source: Grove Art Online; http://www.groveart.com/ (accessed 10/10/2007