Initial studies on fluorine were so dangerous that several 19th-century experimenters were deemed "fluorine martyrs" after misfortunes with hydrofluoric acid. [note 8] Isolation of elemental fluorine was hindered by the extreme corrosiveness of both elemental fluorine itself and hydrogen fluoride, as well as the lack of a simple and suitable electrolyte .   Edmond Frémy postulated that electrolysis of pure hydrogen fluoride to generate fluorine was feasible and devised a method to produce anhydrous samples from acidified potassium bifluoride ; instead, he discovered that the resulting (dry) hydrogen fluoride did not conduct electricity.    Frémy's former student Henri Moissan persevered, and after much trial and error found that a mixture of potassium bifluoride and dry hydrogen fluoride was a conductor, enabling electrolysis. To prevent rapid corrosion of the platinum in his electrochemical cells , he cooled the reaction to extremely low temperatures in a special bath and forged cells from a more resistant mixture of platinum and iridium , and used fluorite stoppers.   In 1886, after 74 years of effort by many chemists, Moissan isolated elemental fluorine.