Last week, the episode ended with a great piece of music: The Hollies’ “On a Carousel,” from 1967. It was a callback to the classic “Carousel” episode of Mad Men, in which Jon Hamm’s Don Draper wowed Kodak, and a nation of viewers, by describing a new slide projector gizmo as a deliverer of memories and love. That was as Mad Men was taking off. Now, as it winds down, Don is perched in front of a new IBM Selectric, grudgingly pecking out tag lines for Peggy – who once was his secretary, and now is his copywriting boss. Don’s life has really gone 180 degrees, round and round… on a carousel.