This sub-series consists of 74 field books written by Canadian employees of the International Waterways Commission (IWC) sent to the regions of Lake Ontario, Niagara and St-Lawrence Rivers to make topographical surveys for setting the maritime boundary between United States and the Dominion of Canada at the start of the 20th century.
In 1908, a "Treaty between Great Britain and The United States providing for the more complete definition and demarcation of the international boundary between the Dominion of Canada and the United States" was signed in Washington adding the mandate of the International Waterways Commission. Article IV of the Treaty stipulated that the Commission was responsible for the determination of the maritime boundary between the intersections of the land border with the St. Lawrence River and through the Great Lakes and communication waterways to the mouth of Pigeon River (on the western shore of Lake Superior).
In April 1908, Canadian Prime Minister Wilfred Laurier instructed the Canadian members to start delineating the maritime boundary. The survey work took place from 1909 to 1913.
In 1915, the Commission presented a report titled "Report of the International Waterways Commission upon the international boundary between the Dominion of Canada and the United States through the St. Lawrence River and Great Lakes as ascertained and re-established pursuant to Article IV of the Treaty between Great Britain and the United States signed 11th April, 1908". This report described all previous efforts to ascertain the maritime boundary through the Great Lakes. In 1915, the IWC dissolved and its responsibilities transferred to the International Boundary Commission, which had been created in 1908.
At the end of the field work, the surveyors handed these field books to the Canadian president of the Commission, William James Stewart, also the Chief Surveyor of the Canadian Hydrographic Service in the Department of Marine and Fisheries, which then held most of maritime and land surveys responsibilities of the Canadian government.
In 1936, the Hydrographic Survey Service was transferred to the newly created Mines and Resources Department, under the Surveys and Engineering Branch. Those field books were transferred to the Surveyor General Branch, in charge of the boundaries delimitation, where they were kept since.
