Glass

“Don’t try this at home,” warns Robert Ponton as he chews up his drinking glasss to emphasize his point that glass is completely recyclable. He then goes on to share the secret of “glass” used in the movies (sugar and Karo syrup) as well as to survey the history of real glass, from the ancient use of obsidian for tools and weapons up to the fiber optics that “make our computers talk to each other.”