William was the son of James Jackman and Beatrice Mitchell[1]. He married Mary C. Stone, daughter of Irvin Stone and Alvora Livingston, on December 25, 1901 in Leeds and Grenville, Ontario, Canada. As a widower he married Vera Mabel Tryon in Havre, Hill, Montana on July 6, 1915.[2] They do not appear to have had any children.
From his FindaGrave memorial:
University College Class of 1896, a member of the Department of Political Economy of the University of Toronto 1915-1941 - Professor of Transportation at University of Toronto. Published "Canada's railroad problem: an analysis of the advantages and objections to Government Ownership of Canadian Railways..." 1917. "Economics of Transportation", 1926. "The St. Lawrence waterway project", 1932. "Economic principles of transportation", 1935. "Essays in transportation in honour of W T Jackman", 1941.
↑ Montana, County Marriages, 1865-1950, FamilySearch (https://familysearch.org/ark:/61903/1:1:F333-5LY), W. T. Jackman and Vera M. Tryon, 06 Jul 1915; Marriage, Havre, Hill, Montana, county courthouses, Montana; FHL microfilm 1,902,811
Additional Sources
1881 Census of Canada: Census Place: Derby, Grey North, Ontario; Roll: C_13262; Page: 37; Family No: 156 (Ancestry.com)
1891 Census of Canada: Census Place: Tiny, Simcoe East, Ontario; Roll: T-6368; Family No: 199 (Ancestry.com)
1921 Census of Canada: Reference Number: RG 31; Folder Number: 101; Census Place: Toronto (City), York South, Ontario; Page Number: 5 (Ancestry.com)