"The city had been built, inexplicably, in the middle of a mud flat, which necessitated raising portions of the downtown area on stilts above the sloshy earth, giving Chicago the first of many nicknames: Mud City.", Paddy whacked: The Untold Story of the Irish American Gangster, Thomas J. English, HarperCollins (c) 2005, ISBN0-06-059002-5, pp73-74, https://www.harpercollins.com/9780060590031/paddy-whacked