We see glass objects every day, and often don’t think much about them. Mass-produced glass has become so cheap we barely think about the things it allows us to do.

In fact, glassblowing has a fascinating history dating back to the late first century BCE.

Roman experimentation with recycling glass permanently changed everyday life, facilitating a vast expansion of trade and economic activity.

And the way glassblowing was done during the Roman era is still very similar to the way we do it today.

Of course, glass was invented long before glassblowing.

The earliest glass beads were made in Ancient Mesopotamia in the second half of the third millennium BCE (around 4,500–4,000 years ago).

The first closed glass vessels followed about a thousand years later (around 1500–1400 BCE) in Mesopotamia and nearby Ancient Egypt.

These early glass vessels were moulded, and the closed containers were made with a process called core-forming.

This involved sticking a plug made of animal dung, clay, mud and sand onto the end of an iron rod. Molten glass the consistency of treacle (and over 1,000°C), was poured over the plug. After it was worked, decorated, and cooled, the hardened plug had to be scraped out manually.

Later vessels were made with casting techniques (which also involved heating glass and laying it atop a mould). This also required long periods of working, and........

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