Just had a look at vol 1 of Boyd 'the IOM Railway' - Mcdowall was appointed 31st mar 1898 taking up post 12 april (described as a Caledonian railway employee contacted via Charles Forman of Forman's + McCall (?civ engs?). described as a sick man he died 26 oct 1900 in England with the replacement in service 17 jan 1901.