Abstract
François Joseph Jérôme Nicklès (1820-1869), a French chemist and pharmacist, carried on extensive research in the areas of crystallography, isomorphism, polymorphism, electromagnetism, physiology, fermentation, the theory of odor and smell, fluorine and its derivatives, etc. His results confirmed bismuth belongs to the nitrogen group, the formation of propionic acid during the fermentation of tartaric acid, and fluorine is present in most parts of the organism. His work on fluorine and derivatives led to his death at an early age.