1. The Magic of Glass
To see a world in a grain of sand...
— William Blake
(And sand is a main ingredient of glass.)
Upon reflection, glass is truly an extraordinary substance. When malleable in that temperature range between solid and liquid (roughly 1200°F/650°C to 2000°F/1100°C) it can be manipulated as easily as clay by the potter, it can be cut with scissors like cloth, or drawn into threads thinner and stronger than silk. It can be rolled into plates, drawn into sheets, and poured or blown into molds.
Its transparent optical qualities have made lenses possible. Think of the countless people who would have been too functionally blind to contribute to society without eyeglasses (including this author) — how many geniuses (such as Benjamin Franklin) have needed eyeglasses, whose contributions would never have come to be without them. In fact, the explosion of learning in the Renaissance may be due in part to spectacles, in wide use in the 15th century (about the time the printing press was invented).1 Eyeglasses have added decades of reading to human life, and even though they are now generally made of special plastics, we still call them ‘glasses’.
And the optical properties of glass have opened to human view both the infinitely large Cosmos (with telescopes) and the infinitely small realm of the microbe and smaller (with microscopes). Without glass we would still believe that the sun revolved around the earth, and would still have no clue to the cause of the Plague.
It’s also impossible to imagine modern chemistry and medicine without glass. It is extremely chemically inert, making it possible for chemists to use test tubes and other apparatus that don’t chemically react with their experiments. Medical researchers use Petri dishes and other apparatus made of glass because they won’t react with the bacteria and drugs under study. And being transparent, scientists can see what’s going on inside. (Perhaps using a microscope, with its glass lenses.) And glass is easy to clean, easy to seal, and easy to transform in shape.
Nor would modern electronics have been possible without glass. The first generation of radio and television as well as early computers — all used ‘vacuum tubes’ made of glass. Glass is strong enough to withstand the pressure of the atmosphere when the air is evacuated, and glass is also an excellent electrical insulator. High-end audio equipment still uses glass ‘tubes’.
And let’s not forget the light bulb: incandescent, fluorescent, and neon are all made with glass.
Or consider the simple windowpane — in your house and your car: glass lets the light in but keeps the elements out. Until the invention of plastics in very modern times there was no other choice but glass, and even today it is still generally the most economical option. Imagine a house in northern climates before glass — in winter your options for light would be dim candles, or open windows that let in the wind, rain and snow.
And then there are the artistic uses of glass, from stained glass windows to incredible creations of glass — blown and otherwise — by millennia of artisans.
And as humanity inevitably adopts a more renewable economy, glass will continue to play an important role: usually when substances (like plastic) are re-melted to be reused, they degrade. Glass, however, can be remelted and reused countless times without any measurable degradation.
And if all of that weren’t enough, you can also make music with glass!
As we shall see...