Laminated glass

In November 1903, French chemist Édouard Bénédictus knocked a glass flask off a shelf in his Paris laboratory. The flask shattered but didn't disintegrate—the broken pieces clung together in a spider-web pattern, held by an invisible film. His assistant explained: the flask had previously held cellulose nitrate solution, which evaporated and left a transparent coating.

The accident was possible because cellulose nitrate—one of the first synthetic plastics—already existed. Developed in the mid-19th century by treating cotton with nitric acid, it had found uses in photography and medicine. Glass manufacturing had matured through the Pilkington process. The automobile was proliferating rapidly—Ford's Model T would debut in 1908—but vehicles used ordinary window glass that shattered into lethal shards during accidents.

Bénédictus thought no more of it until he read of an automobile accident where a young girl was severely cut by shattered glass. He returned to his laboratory and manufactured the first sheet of laminated safety glass the next day: cellulose nitrate sandwiched between two sheets of glass under pressure and heat. He called it Triplex and filed a patent in 1909.

Production was painstaking and expensive. Automobile manufacturers balked at the cost. World War I changed everything—sudden urgent demand for gas mask lenses, airplane windshields, tank viewports, submarine portholes. Reginald Delpech's English Triplex Safety Glass Company scaled rapidly.

In late 1919, Henry Ford began working with Pilkington to perfect large-scale production. Ford called his version "Indestructo Glass" and made it standard on the Model A in 1927. Cellulose nitrate yellowed with age, so in 1936, polyvinyl butyral (PVB)—developed in 1927—proved superior: it didn't yellow, bonded more strongly, blocked UV, and dampened sound. By 1939 it became the industry standard.

Laminated glass enabled entirely new vehicle architectures—larger windshields, curved designs, structural support during rollovers. Beyond automotive, it found use in hurricane-resistant windows, bulletproof barriers, and cockpit canopies. The accident in Bénédictus's laboratory wasn't genius; it was inevitability meeting preparation.