1767 - began his medical training with a short apprenticeship to William Birtwhistle, an apothecary. 1775 - graduated MD at Edinburgh University. 1778 - fired a gun through a window and killed a man who had been creating a disturbance in his garden. Although this was generally accepted as an accident, he was disowned by his Quaker meeting and left the county to set up practice in Denbigh. 1782 - had moved to London. 1784 - admitted as a licentiate of the Royal College of Physicians. 1791 - appointed physician to the London Smallpox and Inoculation Hospital at St Pancras and elected to the Linnean Society. 1797 - published a pamphlet aimed at a popular audience, advocating inoculation. 1798 - following Edward Jenner's discovery of vaccination, advocated it instead of inoculation.