I just read an interesting article by Jason Marcus Hinds of gogeomatics.ca that takes an introductory look at five of Canada’s most influencial cartographers. There are some big names on the list (Thompson and Fraser to name but two), and the article includes a couple of visuals that illustrate the surveying activities of these and other important explorers in Canada’s geographical history. Definitely worth a quick read.
A short excerpt for you:
Thompson was a fur trader and surveyor by profession who contributed to mapping and exploration in Canada through charting of the entire Columbia basin. This exercise included exploration of the length of the Columbia River while charting the surrounding areas. Over the span of his career, he mapped more than one fifth of the entire North American continent. Thompson’s maps were highly accurate and precise, bringing him prestige and respect as a pioneer in the field of mapping.