1769 Born in London, son of John Arnold and his wife Margaret[1]
c.1783 Apprenticed to his father.
Subsequently went into partnership with his father, trading as John Arnold and Son
1792 Went to Paris to work with the esteemed clockmaker Abraham Louis Breguet until the revolution obliged him to return to London.
1796 After his father retired, his son continued the business at the shop at 102 Cornhill in the City of London.
1804 The Board of Longitude made an award to Thomas Earnshaw of £3000 for his escapement. They investigated the priority of invention between Earnshaw and John Arnold but came to no firm conclusion. However, they did decide that, in recognition of Arnold's work, his son John Roger should be given a similar award.
1830 John Roger Arnold was still one of the leading chronometer-makers in London
1830 He formed a partnership with Edward John Dent, known as Arnold and Dent
1840 The partnership with Edward John Dent ended.
1843 Died in Chigwell[2]