John Dalton was an English scientist who first developed the atomic theory and did much research in the area of color blindness. He was a physicist, meteorologist and chemist.
Early life: John Dalton was born to a Quaker family in Eaglesfield, England in September 6, 1766. His brother obtained a school from an old friend and began teaching but there was a lack of teachers so he called upon Dalton to teach as well at age 12! In 1793 he moved to Manchester to teach mathematics at a college. While there he published a book on meteorology and gained some fame and respect, He upheld the view, against contemporary opinion, that the atmosphere was a physical mixture of approximately 80 percent nitrogen and 20 percent oxygen while there he established several other theories and did some work on color blindness
Atomic theory: By far Dalton’s most important and influential work in chemistry was his work on the area of the atomic theory. It is unknown exactly how and what Dalton based his theory on. His own later recollections on the subject were incomplete. He claimed that atoms of the same element could vary in size and mass. While other scientists of his day believed that if two atoms were of the same element then they would be exactly the same in size, mass and shape. John Dalton developed the atomic theory as we know it today.
Later life: John Dalton later moved to his sister’s house where he conducted many small experiments of his own and observed the stars. Dalton suffered a minor stroke in 1837, and another one in 1838, after which he had a speech problem until death. He was still able to continue experiments. In May of 1844 he had still another stroke; on the 26th of July he recorded with shaking hands his very last meteorological observation. On July 27, in Manchester, Dalton was found dead on the ground by his attendant. Some people believe he was murdered by his sister for his money, but that is speculation with no proof.
John Dalton was a brilliant scientist and physicist but what he most loved to do most was observe the stars. Growing up in a rural home, he spent his days watching the stars and continued watching them to his last days. Today color blindness is often referred to as Daltonism in his honor.