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Hello, around 5,000 years ago the Egyptians were using glass to make beads, melting sand

at very high temperatures and cooling it rapidly in water.

Ever since glass has been deeply puzzling, scientific advances reinforce the urge to understand

glass from spectacles, prisms and telescopes to optical fibers and the windows on space

rockets to mobile phone screens today.

How can it be made stronger or clearer and what does it do to light?

Many glass makers have kept their methods secret, in Venice in the Middle Ages, disclosure

was punishable by death.

Scientists still don't precisely understand what happens when sand moves from a molten

state to a hard transparent phase when it appears to have solid and liquid properties.

Let me discuss glass, one of the great scientific puzzles, are Damitini Donald, professor of

experimental physics at the University of Cambridge and Master of Church of College Cambridge,

Jim Bennett, former director of the Museum of the History of Science at the University of

Oxford and keeper emeritus of the Science Museum and Paul McMillan, professor of chemistry

at University College London.

A thinning Donald, glass starts as something solid, mostly sand, then it's molten and once

cooled, it's a very different solid.

What do we need to know about the different states of matter in that process?

The three familiar states of matter are gases, liquids and solids and if we think of something

...