During his time as chief engineer for the Canadian Pacific Railway, he worked primarily as a surveyor for the expansion of routes across Winnipeg addition to the west.
Fleming was the patron counting the hours 1-24 and world time. His initiative led in 1884 to the Washington Meridian Conference, on the Meridian at Greenwich was recommended, among others, as the reference meridian for the world time. The resulting division of the earth into 24 time zones has many local times that have previously been applied within a single time zone preferred Fleming. Otherwise, however, he remained loyal to his utopia, " that an enlightened cosmopolitanism ultimately would not need more than a single universal tag" with world time.
Later he brought the laying of a submarine cable by the Pacific Ocean between Canada and Australia, which the British government telegraph network was global closed and earned him the honorary title of Sir.
He was the founder of the Royal Canadian Institute, a science organization in Toronto and in 1882 a founding member of the Royal Society of Canada.