A puff of glass

Fourth generation glassblower John Lehman makes a glass trap for a vacuum system as specified by chemistry professor John Gryder. Mr. Lehman and Dr. Gryder explain the process of making the glass piece, including "pulling points," using both cross fires and torch to heat the glass as it evolves. A brief film explores the history of glass, from volcanic obsidian to the man-made glass of the Egyptians. In 300 B.C. the blowpipe was invented, opening the way to new uses of glass. At the first American colony in Jamestown, Virginia, Captain John Smith built a glass factory. A film shows a reenactment of an early American glassblower making a bottle. Dr. Gryder displays historical tools still used in the art plus modern ones that have been added. Manufacturers of glass have changed the assumed properties of glass, making it pliant, strong, heat and cold resistant, etc. for new functions. Mr. Lehman completes the glass piece, inserts it in the vacuum system, and tests it for leaks.