Escapement escapement was used for a washstand design in ancient Greece and the Hellenistic world, particularly Ptolemaic Egypt, while liquid-driven escapements were applied to clockworks beginning in Tang dynasty China and culminating during the Song dynasty. However, the fully mechanical escapement in mechanical clocks was first invented in medieval Europe during the 14th century. The importance of the escapement in the history of technology is that it was the key invention that made the all-mechanical clock possible. The invention of the first all-mechanical escapement, the verge escapement, in 13th-century Europe initiated a change in timekeeping methods from continuous processes, such as
Energy release component Energy release component The energy release component (ERC) is a number related to the available energy (BTU) per unit area (square foot) within the flaming front at the head of a fire. Daily variations in ERC are due to changes in moisture content of the various fuels present, both live and dead. Since this number represents the potential "heat release" per unit area in the flaming zone, it can provide guidance to several important fire activities. It may also be considered a composite fuel moisture value as it reflects the contribution that all live and dead fuels have to potential