The Smithsonian Libraries created short videos demonstrating several "animated" books. Seen above is the Animated Circus Book from 1943. I'm also intrigued by Dean's New Book of Dissolving Views from 1860. It's a great idea to share these wonderful books through video but I wish the Smithsonian would have zoomed in closer and gone through all the pages. (Thanks, Musebrarian via Submitterator!)