The Medford Public Library, Medford Historical Society & Museum, and Friends of the Medford Public Library continue their History Book Group with a virtual discussion of "Spying on the South: An Odyssey Across the American Divide," by Tony Horwitz. In the book, Horwitz traces Frederick Law Olmsted's 1850s journey as an undercover correspondent in the South for the up-and-coming New York Times. It reveals much about the mind of Olmsted, who would become America's greatest landscape architect, as well as…