HELMHOLTZ, HERMANN VON

born Aug. 31, 1821, Potsdam, Prussia died Sept. 8, 1894, Charlottenburg, Berlin, Ger. original name Hermann Ludwig Ferdinand Helmholtz German scientist and philosopher who made fundamental contributions to physiology, optics, electrodynamics, mathematics, and meteorology. He is best known for his statement of the law of the conservation of energy. He brought to his laboratory research the ability to analyze the philosophical assumptions on which much of 19th-century science was based, and he did so with clarity and precision.