1820-1893

Irish physicist whose research described the scattering of light by particles. Tyndall's work showed why it is possible to view a beam of light passing through a cloudy liquid from the side. The Tyndall effect, as it is known, is used in water quality analyses and in looking for small (dust-sized) particles in space. Tyndall also helped to popularize the work of James Maxwell (1831-1879), who discovered that heat is related to the random motions of molecules.