Chemist John Dalton was born September 6, 1766, in Eaglesfield, England. During his early career, he identified the hereditary nature of red-green color blindness. In 1803 he revealed the concept of Dalton’s Law of Partial Pressures. Also in the 1800s, he was the first scientist to explain the behavior of atoms in terms of the measurement of weight. Dalton died July 26, 1844 in Manchester, England.