Louis Dufour (17.02.1832-14.11.1892) was a Swiss physicist. He was born in Lausanne. He studied in Paris (1850-53). In 1853-77 he was professor at the university in Lausanne.
His work was in the field of molecular physics, heat and optics. In 1872 he discovered the effect by which the temperature changes when gases diffuse through porous partitions (the Dufour effect), a phenomenon the reverse of thermal diffusion. He studied the solidification of liquids, and of water in particular.