Escapement a statue of an angel to follow the sun, the consensus is that this was not an escapement. The first mechanical escapement, the verge escapement, was used in a bell ringing apparatus called an "alarum" for several centuries before it was adapted to clocks. In 14th-century Europe it appeared as the timekeeper in the first mechanical clocks, which were large tower clocks. Its origin and first use is unknown because it is difficult to distinguish which of these early tower clocks were mechanical, and which were water clocks. However, indirect evidence, such as a sudden increase in cost and construction
Mechanical energy isolated system remains constant in time, as long as the system is free of friction and other non-conservative forces. In any real situation, frictional forces and other non-conservative forces are present, but in many cases their effects on the system are so small that the principle of conservation of mechanical energy can be used as a fair approximation. Though energy cannot be created or destroyed in an isolated system, it can be converted to another form of energy. In a mechanical system like a swinging pendulum subjected to the conservative gravitational force where frictional forces like air drag and friction