1817 - Robert Hawthorn began business as a general engineer and repairer of colliery machinery. 1820 - Robert's brother William joined the firm and they built their first marine engine. 1831 - built their first steam locomotive for the Stockton and Darlington Railway. 1866 - Robert Hawthorn died. 1870 - William Hawthorn retired from the business. 1886 - merged with A. Leslie & Co to become R&W Hawthorn, Leslie & Co Ltd.