Using some nifty geometry (he was a mathematician after all) he projected the earth onto a cylinder and then unrolled it. This means that the earth’s surface gets more and more stretched the further away you get from the equator.
At the poles, for example, all meridians converge to a single point, but this projection stretches that point to the length of the equator!
But making meridians parallel is not enough to fix the bearing problem.
) in the third century BCE by measuring the heights of shadows in different parts of Egypt.
But until the 16th century the most used maps in the west were ones drawn using Ptolemy’s projection and his grid system.
A map curved at the edges, using elliptical projections, to preserve the correct distance between places close to the poles.
Enter Gerardus Mercator, a mathematician, philosopher and globe-maker from Flanders (modern-day Belgium).
The Mercator Projection To really grasp the issues with a 2D projection of the world, one must understand the difference between parallels and meridians.