PPT Slide
Mercator’s projection is not the only one that can render loxodromes (rhumb lines) as straight lines and correct directions. But it is the only one that does it for all loxodromes. The projection shown here has all loxodromes from one location as straight lines, going in their correct direction and with correct length. The present map is focused on 45 degrees north latitude and the Greenwich meridian, near Le Havre. When centered on the equator the north and south hemispheres are symmetrical.
W. Tobler, 1966, “Notes on Two Projections: Loximuthal and Two Point Equidistant”, The Cartographic Journal, (Dec):87-89.