Jean Charles Athanase Peltier (; ; 22 February 1785 – 27 October 1845) was a French physicist. He was originally a watch dealer, but at the age of 30 began experiments and observations in physics. Peltier was the author of numerous papers in different departments of physics. His name is specially associated with the thermal effects at junctions in a voltaic circuit, the Peltier effect. Peltier introduced the concept of electrostatic induction (1840), based on the modification of the distribution of electric charge in a material under the influence of a second object closest to it and its own electrical charge. Biography Peltier trained as a watchmaker; until his 30s was a watch dealer. Peltier worked with Abraham Louis Breguet in Paris. Later, he worked with various experiments on electrodynamics and noticed that in an electronic element when current flows through, a temperature gradient or temperature difference is generated at a current flow. In 1836 he published his work and in 1838 his findings were confirmed by Emil Lenz. Peltier dealt with topics from the atmospheric electricity and meteorology. In 1840, he published a work on the causes of hurricanes. Peltier's numerous papers are devoted in great part to atmospheric electricity, waterspouts, cyanometry and polarization of sky-light, the temperature of water in the spheroidal state, and the boiling-point at high elevations. There are also a few devoted to curious points of natural history. His name will always be associated with the thermal effects at junctions in a voltaic circuit, a discovery of importance comparable with those of Seebeck and Cumming. Peltier discovered the calorific effect of electric current passing through the junction of two different metals. This is now called the Peltier effect (or Peltier–Seebeck effect). By switching the direction of current, either heating or cooling may be achieved. Junctions always come in pairs, as the two different metals are joined at two points. Thus heat will be moved from one junction to the other. Peltier effect The Peltier effect is the presence of heating or cooling at an electrified junction of two different conductors (1834). His great experimental discovery was the heating or cooling of the junctions in a heterogeneous circuit of metals according to the direction in which an electric current is made to pass round the circuit. This reversible effect is proportional directly to the strength of the current, not to its square, as is the irreversible