You count on it for comfort. You depend on its protection. You look at it every day, sometimes for hours at a time. How often, though, do you think about your windshield? If you're like most people, probably not that often. How much do you know about this innovation that we take for granted? Read on to discover the fascinating history of the evolution of the windshield.
Origins
In the early days of the automobile (then called the horseless carriage), driving goggles were a part of standard driving attire. While the goggles were undoubtedly fashionable, drivers thought it necessary to have protection from flying bugs, rocks, and the elements as they drove. In the early 1900's that necessity gave birth to the first windshield. Early windshields weren't made from glass at all, but from pieces of canvas with viewing holes made from thin sheets of mica called isinglass curtains. These "curtains" could be taken down and stored when the weather was favorable. This technology had been used for window coverings for centuries before the advent of glass. While it was extremely light and got the job done, mica wasn't particularly durable or clear to see through and certainly left a lot to be desired when it came to style.
Glass
Eventually people got fed up with the poor visibility and relative lack of durability that isinglass offered, and the first glass windshields hit the scene. Typically, these consisted of two panes of plate-glass with a hinged joint in the middle so that the windshield could be folded down in if the driver wanted to enjoy the breeze. The problem was that in an accident, the glass break into long razor-sharp shards that had a pesky tendency of lethally wounding people. Drivers found this objectionable, and a string of lawsuits were filed against the Ford Company. Around this same time, Henry Ford himself allegedly suffered minor injuries from an incident involving a broken windshield. The plate-glass, he decided, had to go.
Toughened Glass
Ford, looking for an alternative to dangerous untreated glass, began installing toughened glass windshields in his new automobiles. Toughened glass was heat-treated making it more rigid than untreated glass and thus it would shatter into thousands of tiny and mostly harmless pieces in a crash. Great, right? Not necessarily. While it is still commonly used in vehicle side and rear windows today, this harder glass lacked the flexibility of untreated glass and could fall apart when struck with small rocks or other road debris. Back to the drawing board.
Laminated Glass
Way back in 1903 (when most of the automotive world was still using isinglass curtains), a French chemist named Edouard Benedictus discovered that glass coated with a collodion film would hold its shape when cracked. It was certainly interesting, but the discovery wouldn't have much significance until more than a decade later. In 1920, Edouard's discovery inspired automakers to begin using laminated glass, a glass sandwich with a tough and flexible film pressed in the middle. This glass, which has been refined and perfected up to the present-day, is tough, safe, and can be easily repaired when chipped.
The world of auto glass has certainly come a long way in the past century and it's a good thing, too! Data from the National Highway Traffic Safety Administration suggests that well-maintained safety glass windshields contribute to saving thousands of lives each year. While driving goggles may have looked cool, drivers everywhere can thank the modern windshield for making their daily commute safer and more pleasant.