Cartographic Development of the Atlas of Canada

Summary

In 1949, the Canadian government initiated the production of a new National Atlas to depict the country's economic and physical features, replacing an earlier 1915 edition. An interdepartmental Atlas Committee was formed, encompassing various scientific and professional experts, and subcommittees were tasked with compiling data across domains such as agriculture, climate, transportation, and natural resources. The cartographic design involved rigorous planning of base maps at multiple scales (1:2,500,000 to 1:50,000,000) derived from a master map on a Lambert conformal conic projection with standard parallels at 49° and 77° N, extended by a polyconic projection above 80° N. To ensure clarity, base maps were rendered in neutral grey-violet lines with light blue water, allowing economic and statistical overprints to stand out. A key challenge was color selection; by employing contact screens (dot and line screens of various rulings) and a limited palette of eight colours, over fifty distinguishable tints were achieved while reducing the average number of print runs per sheet to nine. Master negatives on matte plastic facilitated accurate overlays and corrections. The project demanded precise photomechanical procedures, multiple exposures for colour plates, and strict proofing stages to guarantee colour fidelity. Although concurrent with routine topographic mapping, the Atlas production served as advanced training in modern cartographic methods, enabling staff to develop innovative solutions for complex thematic mapping and significantly advancing national atlas cartography.