Darwin Correspondence Project

German chemist and mineralogist. Studied oriental languages and medicine; worked in the private laboratory of Heinrich Friedrich Link in Berlin, where he discovered isomorphism in crystal structure in 1819. Worked in the laboratory of Jöns Jacob Berzelius, and studied at mines and metallurgical works in Sweden, 1820–1. Professor extraordinarius, Berlin, 1821; professor, 1825. Made several important discoveries, including crystal dimorphism, an early catalyst theory, and a method for determining vapour densities of elements.