Christoph Friedrich, a distinguished German chemist, born at Eisleben in 1770. In his nineteenth year he was appointed to superintend a manufactory at Ochsenfurt in Franconia; from which town at the end of two years he removed to Mulhausen, where he conducted the experiments by which he first became known. In 1808 he graduated as a physician at Rinteln, and in the following year at the university of Erfurt. In 1813 his health gave way from the long imprisonment which he suffered, consequent upon the siege of that town. He then removed to Aix-la-Chapelle, where his eyesight became affected; and when he retired finally to his birth-place, he was nearly blind. He died in 1818. His works are very multifarious, and, besides numerous separate treatises, comprise translations from the English, and contributions to the principal scientific journals of his native country.