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.
I may not own a cape or the Batmobile, but this is the next best thing. With this collectible mug, I can quite literally hold the adventures of Batman and Robin in my hands! Made in 1995, this piece was produced in partnership with DC Comics to commemorate Batman Forever. The clear glass has a textured and slightly pebbled appearance and a semi-frosted finish, which showcases the embossed design even more clearly. The surface features Robin on one side, complete with his suit and R badge.