law of diminishing returns. A concept in economics that if one factor of production (number of workers, for example) is increased while other factors (machines and workspace, for example) are held constant, the output per unit of the variable factor will eventually diminish.
History of glass. The history of glassmaking can be traced back to 3500 BCE in Mesopotamia, but Mesopotamians may have created second-rate copies of glass objects from Egypt, where this complex craft actually originated. Other archaeological evidence suggests that the first true glass was made in coastal north Syria, Mesopotamia or Egypt.
By the middle of the 19th Century the use of glass bottles and jars was on the rise and so was the development of bottle closures. In 1856 a screw cap was invented with a cork disc attached to seal glass jars. From 1856 to around 1915 most beer bottles used a wire attached mechanical cap. This style of cap is still being used with some modifications. The origins of the bottle cap we know it started in 1890 with William Painter.