to Chicago and took a position with the architect L. G. Laurean. When the Great Chicago Fire hit the city in October 1871, it seemed as if there would be endless work for architects, but Burnham chose to strike out again, becoming first a salesman of plate glass windows, then a druggist. He failed at the first and quit the second. He later remarked on "a family tendency to get tired of doing the same thing for very long". Career At age 26, Burnham moved on to the Chicago offices of Carter, Drake and Wight where he met future business partner John Wellborn Root, who was 21 and four years younger than Burnham. The two became friends and then opened an architectural office together in 1873. Unlike his previous ventures, Burnham stuck to this one. Burnham and Root went on to become a very successful firm. Their first major commission came from John B. Sherman, the superintendent of the massive Union Stock Yards in Chicago, which provided the livelihood – directly or indirectly – for one-fifth of the city's population. Sherman hired the firm to build for him a mansion on Prairie Avenue at Twenty-first Street among the mansions of Chicago's other merchant barons. Root made the initial design. Burnham refined it and supervised the construction. It was on the construction site that he met Sherman's daughter, Margaret, whom Burnham married in 1876 after a short courtship. Sherman commissioned other projects from Burnham and Root, including the Stone Gate, an entry portal to the stockyards which became a Chicago landmark. In 1881, the firm was commissioned to build the Montauk Building, which was then the tallest building in Chicago at the time. To solve the problem of the city's water-saturated sandy soil and bedrock below the surface, Root came up with a plan to dig down to a "hardpan" layer of clay on which was laid a thick pad of concrete overlaid with steel rails placed at right-angles to form a lattice "grill", which was then filled with Portland cement. This "floating foundation" was, in effect, artificially-created bedrock on which the building could be constructed. The completed building was so tall compared to existing buildings that it defied easy description, and the name "skyscraper" was coined to describe it. Thomas Talmadge, an architect and architectural critic said of the building, "What Chartres was to the Gothic cathedral, the Montauk Block