Glass is one of those materials that is actually designed to go unnoticed. When was the last time that you noticed the glass windows in your office, or the glass windshield on your car? The odds are you only noticed them when there was something wrong, a crack from a stone, or residual rain marks.
Corning have just come out with a new video showing how technical glass can be and what we can look forward to in the near future:
Spray on “Liquid glass” is also hitting the news with its ability to provide a thin (100 nanometer) coating that protects surfaces by preventing bacteria from attaching to them.
Pretty amazing for something that is made from sand!!!
We are used to glass bowls and maybe even have a Pyrex bowl or two at home. I’ve always loved the story about how they were actually discovered, so here is a brief history of Pyrex Glass.
On a rainy winter night in 1901, a speeding train hurtled through the dark.
A signalman stepped from the warmth of his station to warn of a slow freight train ahead on the same set of tracks.
He started to swing his kerosene lantern at the train driver to warn him, but when cold rain hit the heated glass globe, it shattered, extinguishing the signal light.
(This is because if you suddenly cool warm glass it will crack or shatter -you may have experienced this by trying to put a hot drink in a cold glass).
Without a light the signalman shouted at the train to stop, but his shouts were lost in the roar of the train as it sped past the station.
Seconds later came the sound of an enormous collision as the two train’s crashed causing death and destruction 😦
This was a common problem with lantern glass and so scientists frantically tried to make a glass that could withstand sudden temperature changes.
Early experiments proved that if the raw materials contained borax, the glass would be far more resistant to heat and temperature change.
However, the first glasses they made with Borax were so weak chemically that they deteriorated in water (not good on a rainy day).
In their search for a balanced recipe for heat-resistant glass, scientists tried one formula after another, seeking a stable mixture of silica sand and boric oxide.
With little to guide them but trial and error, two scientists found a formula that would combine heat resistance with chemical stability in 1912 (it took 11 years to find a good combination).
Soon after, lantern globes and battery acid jars made of the new glass were in production and lives were saved.
About a year later a young physicist had joined the research team. He had a theory that the lantern glass would make a good cooking dish because it absorbs radiant heat, while most metals reflect it so he took home a jar made from the lantern glass.
That night, the physicist’s wife baked in glass and the next day her husband brought it to the laboratory and everybody ate cake that was baked in the lantern.
The wife used the glass utensil for other recipes, and she reported that food didn’t stick to the glass, cooking time was shorter, the glass didn’t transfer a flavour to its contents, and that she could watch the food brown and know when to take it from the oven.
And that is the history of Pyrex bowls 🙂