Watson was born in Heversham, Westmorland (now Cumbria), and educated at Heversham Grammar School and Trinity College, Cambridge, on a scholarship endowed by Edward Wilson of Nether Levens (1557–1653). In 1759 he graduated as Second Wrangler after having challenged Massey for the position of Senior Wrangler. This challenge, in part, prompted the University Proctor, William Farish, to introduce the practice of assigning specific marks to individual questions in University tests and, in so doing, replaced the practice of 'judgement' at Cambridge with 'marking'. Marking subsequently emerged as the predominant method to determine rank order in meritocratic systems. In 1760 he became a fellow of Trinity and in 1762 received his MA degree. He became a professor of chemistry in 1764 and was elect