The architect Hector Guimard designed the charismatic Métro entrances that are now icons of Paris. These ornate arches were key to the development of “Le Style Guimard,” an aesthetic that consisted of fluid lines and natural forms. Really, what he birthed was France’s Art Nouveau movement. From collections around the globe, Chicago’s Richard H. Driehaus Museum, in collaboration with the Cooper Hewitt, brings together nearly 100 objects demonstrating the breadth of Guimard’s historical importance. —Clara Molot