Richard Zsigmondy

Born Apr. 1, 1865, in Vienna; died Sept. 23, 1929, in Gottingen. Austrian scientist in the field of colloid chemistry. Graduated from the Technische Hochschule in Vienna in 1887 and from the University of Munich (1889). In 1908 he became a professor at the University of Göttingen. In 1898 he began working on the methodology of preparation of colloidal solutions and their ultra-filtration. In 1903, in collaboration with R. Siedentopf, he invented a slit ultramicroscope and, in 1913, the so-called immersion ultramicroscope. He proposed a classification of colloidal particles. Using ultramicroscopy and other methods that he developed, Zsigmondy made numerous studies of the Brownian movement of colloidal particles, coagulation, and other processes. He was awarded the Nobel Prize in 1925.