JOHNSTON, or JOHNSTONE, Thomas Patterson (1835-1915) was listed as an architect in Vernonville, Northumberland County, Ontario in 1864 (Mitchell's Canada Gazetteer and Business Directory, 1864-65) and again in 1865 (Sutherland & Co., Directory of United Counties of Northumberland & Durham, 1865). He is almost certainly the architect with the same name who prepared a Gothic design for the Wesleyan Methodist Church in Bowmanville, Ont. in 1870, as well as the plans for St. Paul's Presbyterian Church in Bowmanville in 1870-71. Just two years later, in 1873, he was credited as the architect of the Presbyterian Church in the nearby village of Columbus, Ont. Johnston was born in Scotland in 1835 and arrived in Canada after 1850, and may have trained or worked in the building trades in southern Ontario.
In 1957, a legal Notice re Missing Heirs for "Thomas P. Johnstone, Architect" was published in the Canadian Statesman [Bowmanville], 7 March 1957, 14, noting that Johnston had arrived from Scotland and England between 1850 and 1860, and his personal possessions included a watch with the inscription "To Thomas Johnstone as Architect of the C.P. Church of Bowmanville from the Congregation - 1 February 1871 ", thus confirming his role as architect and designer. In 1875 he moved to Toronto, and later died there on 13 July 1915 (death notice The Globe [Toronto], 14 July 1915, 6)
BOWMANVILLE, ONT., Wesleyan Methodist Church, Church Street at Division Street, 1869 ( Canadian Statesman [Bowmanville], 21 April 1870, 2, descrip)
BOWMANVILLE, ONT., St. Paul's Presbyterian Church, Church Street at Silver Street, 1870-71 (Canadian Statesman [Bowmanville], 2 Feb. 1871, 2, descrip.; Globe [Toronto], 11 Feb. 1871, 3; J. Squair, The Townships of Darlington & Clarke, 1927, 298-9, descrip.)
COLUMBUS, ONT., Canada Presbyterian Church, 1873 (British American Presbyterian [Toronto], 28 March 1873, 5, descrip.)