Reading all of these fascinating posts reminds me of a consumer product, at least one 'episode' my brother & I enjoyed when we were kids. The 'show' was about dinosaurs. The audio disk (perhaps a 7" LP) contained narration by Walter Cronkite. I think that the 'buy in' entailed purchasing a special purpose projector to project the proprietary slide format. Does this ring a proverbial bell with any of you? If so, then what was the name and manufacturer (a CBS unit since Cronkite was involved?). How many 'titles' were issued? What were those 'titles'? Art (Shiffy) Shifrin