. >> what i want to ask you is about your 1991 book calmaled anature's metropolis" talk be about the republic's nature. what was the theme of that book? >> a history of chicago in the second half of the 19th search vi and the agenda of the book, look at the history of one of the world's great metropolises at the moment it became a great metropolis and chicago was bear lay town. 1848 is sort of the real beginning of chicago's explosion. the town founded in the early 1830s, but it really explodes with the emergence of the railroad in the late '40s, mid-1850s, thereabout. what the book tries to do narrate the history of the city in tondom with the countryside transformed by growth of that city's markets. so the argument becomes, you cannot understand the history of chicago nor can you understand the history of the american middle west or west without seeing city and country as transforming each other. and it's part of this kind of an argument that mark is offering which is, when you put seemingly human thing, eve an city in a larger natural frame, you understand things about that city y