5. Carl Scheele
Carl Wilhelm Scheele was an 18th century pharmaceutical chemist from German. He independently discovered oxygen, but Joseph Priestly published his finding first. He also identified chlorine, hydrogen, barium, tungsten and molybdenum before Humphrey Davy.
During his experiments, Scheele also uses his taste buds to identify different elements and compounds. Cumulative exposure to fluoric acids, lead compounds, mercury and others took a toll on his health. He married to Pohl during his last days, so he can legally pass his pharmacy and possessions to someone.
