A rare copy of James Palmatary’s 1857 map of Chicago is being auctioned next week, Crain’s reports. Only four copies are known to exist of the map, a bird’s-eye view that depicts the city as it was before the Great Fire; this is the only one in private hands. The remaining surviving copies are held by the Chicago Historical Society, the Library of Congress and the Newberry Library. The map is expected to fetch $20,000 to $30,000. [Tony Campbell]