Fiberglass consists of extremely fine glass fibers, made from molten glass extruded at a specified diameter. Glassmakers have experimented with glass fibers throughout history, but mass manufacturing had to wait for the refinement of machine tooling before a practical product could be made possible.
The product commonly referred to as "fiberglass" was invented as a form of insulation by Russell Games Slayter (1896-1964)—he dropped the Russell early in life—and John Thomas of the Owens-Illinois Glass Company in-the 1930s. In 1938 Owens-Illinois and Corning Glass formed Owens-Corning to make fiberglass using Slayter and Thomas's method.
Fiberglass was discovered—like many other scientific discoveries—by accident. While Thomas's assistant, Dale Kleist, was spraying molten glass for a project, tiny fibers formed. Thomas realized the process could be used to improve the production of fiberglass. Thomas and Slayter refined the process, leading to what is known as the steam-blowing method. As the molten glass is extruded through hundreds of tiny nozzles on the "brushing plate," it is hit by a blast of steam or compressed air, which draws out the filaments to extremely long lengths. The important part of Slayter and Thomas's discovery was the method of applying the blast of steam in a way that avoided breaking or disrupting the filaments.
The practical uses of fiberglass are virtually endless. Slayter himself held over ninety patents for fiberglass technologies. Besides insulation, it is used for medical equipment, fire-resistant textiles, electronics, and wall coverings. In 1953 Owens-Corning went into partnership with General Motors on the first car with a body made entirely of fiberglass-reinforced plastic, the Chevrolet Corvette.