The compass needle does not point directly to the North Pole, but is diverted by a great magnetic influence that lies on the Boothia Peninsula in northern Canada. This is sorne 1,400 miles south of the North Pole. There is also a magnetic area near the South Pole. In northeastern United States the compass needle really points west of north, and in the South and West it points east of north. This must be taken into consideration when making long journeys.
Most accurate maps indicate both the true and magnetic north in relation to the region they portray.
Perhaps the most familiar is the auto map published by the various oil companies, but the most complete ones are the topographic maps made by the United States Geological Survey. They not only give complete details of the country, but indicate elevations as well. A knowledge of the elevation in a strange country is important, for it clearly shows how steep are the trails and the roads, and how much of a drop various streams have, thus indicating their swiftness. This is especially important if your journey is by boat or canoe. In reading contour lines, the outside line is the lowest land, while the innermost line shows the highest point.