Glass bottles were mass-produced containers. The common square form was a particularly practical form of packaging, but other shapes were also made. The bottles were blown into moulds and so patterns and, sometimes, the manufacturer's name could easily be incorporated on the base. Bottles of this cylindrical, slightly barrel-shaped form are often called 'Frontinus bottles' after the name most often found on them. The example shown here, however, was made by a glassmaker named Felix.