In 1736, the noted pharmacist and quack doctor Joshua Ward set up the Great Vitriol Works to produce sulphuric acid, using a process discovered in the seventeenth century by Johann Glauber in which sulphur is burned together with saltpetre (potassium nitrate), in the presence of steam. The process generates an extremely unpleasant smell, which caused objections from local residents. The area was also soon home to the world's first industrial production facility for gunpowder, on a site between Twickenham and Whitton on the banks of the River Crane. There were frequent explosions and loss of life. On 11 March 1758, one of two explosions was felt in Reading, Berkshire, and in April 1774 another explosion terrified people at church in Isleworth.