Louis Seize Regulator
Ferdinand Berthoud –
Paris 18th century

One weight precision regulator with Graham anchor-escapement. Spring-driver strike of hours and half-hours on a bronze bell. Temperature compensating seconds pendulum with metal thermometer.

Knife-edge and cup bearing with gimballed suspension of the pendulum.

Calendar with 365 days and seconds in the middle.

This clock shows the epitome of clockmaking by Berthoud for precision regulators that had been ordered by scientific institutions. The pendulum consists of two different types of metal (brass and iron) for temperature compensation. It is made of nine sticks next to each other. Given their different thermal expansion coefficients, these different metals increase the accuracy of the clock.