Surveyors had to find the shortest and most practical way through unknown wilderness. They often had to take shelter out in the open. Surveyors were subjected to sunstroke, frostbite, scurvy, fatigue, isolation, and sickness. Exploring vast areas of Canada meant scaling unclimbed mountains and crossing lakes and rivers not yet on any maps. They had to push their way through dense bush and scramble over rugged terrain, and were also in danger of forest fires, drowning, grizzly bears, rattlesnakes and other wild animals, as well as hordes of pesky mosquitoes.
As survey crews often had to carry their own baggage, they were instructed to carry "...2 pair of pants, 2 coats, 3 flannel shirts, 3 pair of drawers, 6 pair of socks, 1 pair of mitts, 2 pair of strong boots or shoepacks, 1 towel, 1 brush and comb, and a few other small articles; the whole personal outfit need not exceed 30 pounds."
Instructions from the Engineer in Chief to the Staff, by the Canadian Pacific Railway. [Ottawa: s.n. 1875], p. 6-7
Visit the website Canada, by Train