In today’s edition of “things that go boom in the archives” we have a set of nitrate negatives. These were donated by a guy who stored them in his garage in a paper envelope. What makes them go boom? Cellulose nitrate! It is the material that makes the film base that is printed on with the silver emulsion. When cellulose nitrate isn’t happy (too hot, humid or lots of climate fluctuations) it decomposes to a brittle, sticky bubbly mess. The best part is it can spontaneously combust! Tune in sometime in the future for a new edition of “Things that can kill you in the archives” where we discuss why my tetanus vaccination is always up to date.