With a short exhale and immediately blocking the opening of the cane with his finger, the glassblower creates a bubble at the end of his rod. By tilting the tool towards the ground, he uses the action of gravity to lengthen his crystal bubble. Depending on the desired shape, he blows again into the rod, repeating the same gesture. The invention of blown glass dates back to the Roman Empire. This is why it quickly spread to both sides of the Mediterranean basin, before spreading throughout Europe.