It is hard to point to one person as the real progenitor of rock-and-roll music. Ask half a dozen people and you’ll get half a dozen different answers. However, I’ve always picked the same man: Chuck Berry. Chuck passed away this past Saturday at the age of 90, and he had never stopped performing. Please enjoy these two live tracks, “Johnny B. Goode” with John Lennon, and “Nadine,” with Keith Richards.