Lever a place to stand, and I shall move the Earth with it' is a remark of Archimedes who formally stated the correct mathematical principle of levers (quoted by Pappus of Alexandria). It is assumed that in ancient Egypt, constructors used the lever to move and uplift obelisks weighing more than 100 tons. A lever is a beam connected to ground by a hinge, or pivot, called a fulcrum. The ideal lever does not dissipate or store energy, which means there is no friction in the hinge or bending in the beam. In this case, the power into the lever equals
Lever tumbler lock of the lever lock which was designed to detect and prevent picking attempts. Lever locks can be drilled, but usually a template or stencil is required to mark the drilling point, as the lock mechanism is commonly mortised into the door and so it is harder to determine the point at which to drill. Lever tumbler lock A lever tumbler lock is a type of lock that uses a set of levers to prevent the bolt from moving in the lock. In the simplest of these, lifting the tumbler above a certain height will allow the bolt to slide past.