Glassblowing is a technique which inflates moltenglass into a bubble (or parison), with the aid of ablowpipe. A person who blows glass is called aglassblower, while the head of a glassblowing workshop is known as agaffer. The process was invented by Syrian craftsmen fromHama andAleppo between 27 BC and 14 AD, who discovered the previously unknown property of glass that a molten blob can be inflated by introducing a small amount of air into it. It was then adopted across the Roman Empire and has been in use since then. Glassblowing utilises the liquid structure of glass, the atoms being held together by strong chemical bonds in a disordered and random network, which means that molten glass is viscous enough to be blown and gradually harden as it loses heat. This photograph shows a man working on a glass project after removing it from a kiln at Brooklyn Glass in New York City, United States.Photograph credit:Rhododendrites