He also demonstrated an optical telegraph and proposed the use of his clepsydra[4] (water clock) for keeping time on a ship at sea.

Amontons investigated the relationship between pressure and temperature in gases though he lacked accurate and precise thermometers.

Though his results were at best semi-quantitative, he established that the pressure of a gas increases by roughly one-third between the temperatures of cold and the boiling point of water.

Though he came close to finding absolute zero - the theoretical temperature by which the volume of air in his air-thermometer will be reduced to nothing (estimated by him as −240° on the Celsius scale),[6] the discovery would not be complete until at least a century later.

The fire mill is a wheel that makes use of the expansion of heated air to generate motive power.

In 1699, Amontons published his rediscovery of the laws of friction first put forward by Leonardo da Vinci.