It is thought that the first mechanical clock was invented in medieval Europe, and used most extensively by churches and monasteries (mainly to tell when to ring the bells for church attendance). The clocks had an arrangement of gears and wheels, which were all turned by attached weights. As gravity pulled on the weights, the wheels would turn in a slow, regular manner; as the wheels turned, they were also attached to a pointer, a way of marking the hours, but not yet minutes.

The precursor to accurate timekeeping came around 1500, with the advent of the “spring-powered clock,” an invention by German locksmith Peter Henlein (1480–1542). It still had problems, though, especially with the slowing down of the clock as the spring unwound. But it became a favorite of the rich because of its small size, easily fitting on a mantle or shelf.