Welcome to the Glass Age

40 such technology, only subsequently to move to solid state electronics. The key property of glass was that it could hold a high vacuum over many years but also that a leak tight electric connection to the outside could be achieved. This required an understanding of the thermal expansion behavior of both metal and glass. In the middle of the 20 th century, as the load on the hard-wired electrical telephone increased, scientists begin to question the possibility of encoding electrical signals into a light beam and using the transparency of glass for transmission over long distances. This led to widespread use of glass products in the communications Figure 2.9. Lampworking, used both by the scientific and arts communities for secondary processing. Source: Pixabay.