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SAFETY GLASS
By Bill Fawcett
A mistake that meant greater safety for your family and you.
Moving from unmitigated disasters and toward politicians blundering into WWI, let us take a few moments to look at a mistake that had a positive result. There are actually many of these. They range from vulcanization to saccharin. This particular mistake has likely benefited you or a family member directly. Everyone has been in a car accident.
Édouard Bénédictus was working in his lab in 1903 when he had an accident. Bénédictus was a chemist and he was, not surprisingly, working with chemicals. Glass, which reacts to only a few chemicals, is the near-ideal medium for storing or working with almost any concoction. As he worked, Bénédictus accidentally knocked a glass flask off a shelf. A common, everyday mistake that is made more often than scientists will admit. This was long before Pyrex, so Bénédictus was amazed to notice that, rather than shattering, the glass mostly cracked in a spiderweb-like pattern. Investigating, he found that the dropped flask had contained cellulose nitrate. The chemical was adhesive and bonded to the glass, once dry. The cellulose nitrate had left a clear, nearly invisible, coating inside the flask and this caused the glass to crack rather than shatter. He was able to re-create the effect and applied for a patent for laminated glass in 1909.
While shattering windshields were a serious hazard, auto manufacturers did not adopt laminated windshields at first. But Bénédictus’s safety glass did find an immediate use. The eyepieces in gas masks during WWI were made of glass. To prevent them from shattering and blinding soldiers when shells landed nearby, the new lenses were made of laminated glass. Bénédictus’s “mistake” prevented tens of thousands of casualties. By 1927, all auto manufacturers were using laminated windshields and advertised them as a sales point. Gangsters and bank clerks soon also benefited from the chemist’s mistake, as laminated glass in many layers was found to be bulletproof. If you have ever been in a serious auto accident and seen the spiderweb break of a window, remember: if it had not been for Édouard Bénédictus knocking just the right flask off his desk, and being smart enough to see the implications of what he found, you might well have been injured by flying glass shards.
Lamination made auto windows and many other uses for glass safer. It allowed windows on cars to be larger and the styling of automotive vehicles changed dramatically. Because Bénédictus made a mistake and learned from it, when you drive your car, you are safer and can see the world all around you.