In thermodynamics, Henri Benard (1874-1939) was a French physicist noted for his 1900 experimental work on the heat dynamics, or rather fluid mechanics, of “Benard cells”, which formed the basis of his 1901 PhD dissertation “Cellular Eddies in a Horizontal Liquid Layer”, at the College of France. Benard cells later became the classic example of Belgian chemist Ilya Prigogine's 1960s theory of "dissipative structures".