Scientific Articles
In 1822, French physicist Charles Cagnard de La Tour placed a liquid and a flint ball in a two-door pressure vessel built with a gun and heated the liquid in a sealed cannon. He then conducted an experiment to determine whether a product was produced. 1) When the vessel was shaken, a splashing sound was heard as the ball penetrated the liquid-gas interface. However, when the vessel was heated to a temperature sufficiently above the boiling point of the liquid, the sound disappeared. He hypothesized that this was because the densities of the liquid and gas in the vessel were equal, so that a single phase was effectively formed. This represented the first discovery of what are now referred to as supercritical states and critical points.
