During WWI McLennan was scientific adviser to the British Admiralty. In 1915 he was elected to the Royal Society of London (receiving its gold medal in 1928) and in 1917 received the Order of the British Empire. After the war he returned to U of T but spent each summer in Britain, becoming president of the scientific section of the British Association for the Advancement of Science in 1923.
President of the Royal Canadian Institute in 1916, he helped found the NATIONAL RESEARCH COUNCIL and was a member of the ONTARIO RESEARCH FOUNDATION (est 1928). He resigned from U of T in 1932 and moved to England where he continued his pioneering research in the use of radium to treat cancer. He was knighted in 1935.
Author YVES GINGRAS