Great circles are not straight lines on the Mercator projection. Rhumb lines are straight, but not great circles. If you want great circles to be straight line

Great circles are not straight lines on the Mercator projection. Rhumb lines are straight, but not great circles. If you want great circles to be straight lines, use the Gnomonic projection. http://demonstrations.wolfram.com/GreatCirclesOnMercatorsChart/ http://demonstrations.wolfram.com/GreatCirclesOnMercatorsCha... http://en.wikipedia.org/wiki/Gnomonic_projection http://en.wikipedia.org/wiki/Gnomonic_projection