He remained for seven years, until the college's worsening financial situation led to his resignation. At 27, he was appointed teacher of mathematics and natural philosophy at the 'Manchester Academy' in Manchester, a dissenting academy (the lineal predecessor, following a number of changes of location, of Harris Manchester College, Oxford). He acquired much scientific knowledge from informal instruction by John Gough, a blind philosopher who was gifted in the sciences and arts.

Around the age of 23, Dalton may have considered studying law or medicine, but his relatives did not encourage him, perhaps because being a Dissenter, he was barred from attending English universities.

When he was 15, Dalton joined his older brother Jonathan in running a Quaker school in Kendal, Westmorland, about 45 miles (72 km) from his home. ( May 2021) ( Learn how and when to remove this template message) Unsourced material may be challenged and removed. Please help improve this section by adding citations to reliable sources. Dalton's family was too poor to support him for long and he began to earn his living, from the age of ten, in the service of wealthy local Quaker Elihu Robinson. He received his early education from his father and from Quaker John Fletcher, who ran a private school in the nearby village of Pardshaw Hall. John Dalton was born into a Quaker family in Eaglesfield, near Cockermouth, in Cumberland, England. Early life Historical plaque marking birthplace of John Dalton Modern plaque marking birthplace of John Dalton He also researched colour blindness, which he had as a result, colour blindness is known as Daltonism in several languages. He introduced the atomic theory into chemistry. John Dalton FRS ( / ˈ d ɔː l t ən/ 5 or 6 September 1766 – 27 July 1844) was an English chemist, physicist and meteorologist.

Modern atomic theory