Complex sentence: In 1859 he became engineer in chief of mines, and in 1861, upon the death of Louis Cordier, he was appointed professor of geology at the Museum d'Histoire Naturelle in Paris and was also elected member of the French Academy of Sciences.
Split into simpler sentences: In 1859 he became engineer in chief of mines, and in 1861, upon the death of Louis Cordier, he was appointed professor of geology at the Museum d'Histoire Naturelle in Paris. In 1861 he was also elected member of the French Academy of Sciences.