who became director of Göttingen Observatory in 1806. One of the greatest mathematicians of all time, he contributed to the theory of numbers and proved the fundamental theorem of algebra. He also initiated the study of curved surfaces, thus paving the way for the geometry used in general relativity theory. His collaboration with Wilhelm Weber on electromagnetism led to the invention of an electric telegraph, and he worked out the relationship between electric flux and electric field (see Gauss’ law). He also investigated the magnetism of the earth and the motions of planets and asteroids.