The other improvement consists in the combination with a regulating weight applied to the middle of a wooden pendulum rod, of a compensating apparatus, consisting of metal rods of such length ...

It was the first satisfactory demonstration of the earth's rotation using laboratory apparatus rather than astronomical ... This case is fairly simple, because here the earth and the pendulum are not ...

William Thomson (Lord Kelvin) regularly demonstrated the apparatus using his Jacob militia rifle resting on the pendulum guard. His rifle, still in its case with embossed brass powder horn ...