The front part consists of an oxidised clock faceplate with a bi-metallic thermometer in the center.

The left contains a clockwork gear and a metal/paper coil hygrometer.

The right contains two special gears where the clocks chains with the weights where connected to, and a copper wire feather style coil.

The meters still work and as such do move, and the gears on the right are both independently twist-/moveable.

A highres version is available