The first oil works in the world were opened in Bathgate, West Lothian, in 1851 producing oil from shale or coal. However, many Scottish works closed in 1859 as the world's first oil well was sunk in Pennsylvania in the USA and the price of oil dropped. By 1919 the six surviving companies united under the management of the newly formed Scottish Oils. In the same year Scottish Oils was acquired by the Anglo-Persian Oil Company, later to become BP. The BP refinery in Grangemouth was in operation by 1924.