"'John Dalton was a very singular man. A Quaker by profession and practice, he had none of the manners or ways of the world. A tolerable mathematician, he gained his livelihood, I believe, by teaching mathematics to young people ... ; he followed with ardour analogies and inductions. ... I have no doubt that he was one of the most original philosophers of his times, and one of the most ingenious.' Thus did the great scientist, Sir Humphrey Davy, describe...