The Eckert projection is a cylindrical projection, meaning it uses a cylinder to project the Earth's surface onto a flat map. While meridians (lines of longitude) are straight on cylindrical projections, parallels (lines of latitude) are curved.
This means that on an Eckert projection:
* Meridians will be straight lines running from the North Pole to the South Pole.
* Parallels will be curved lines that are further apart near the equator and closer together near the poles.
Therefore, north on an Eckert projection will only be straight along the central meridian. As you move away from the central meridian, the direction of north will appear to curve.
