1790-1845

English chemist who invented the Daniell cell battery, as well as the dew-point hygrometer. Daniell's career began in the sugar-refining industry, to which he made several improvements. He also did significant work in the lighting industry, before making a major contribution to the field of meteorology with his invention of the hygrometer, an instrument that measured relative humidity, or the dew point. Daniell was probably best known for his invention of the Daniell cell, a battery that had more lasting power than the previous zinc-copper voltaic battery. In his lifetime, Daniell was also active as an educator, philosopher, and writer.