Lever tumbler lock
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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.
'Double acting' Lever tumbler locks were invented in 1778 by Robert Barron of England. These required the lever to be lifted to a certain height by having a slot cut in the lever. So lifting the lever too far was as bad as not lifting the lever far enough.