Mercator projection

What it is

A conformal cylindrical projection in which lines of constant bearing (rhumb lines) appear as straight lines, allowing the navigator to plot a course with rule and compass. The reference world map of oceanic navigation.

The mathematical basis of the projection was published by Edward Wright in 1599, since Mercator had worked by graphical methods.

What it led to

• The systematic oceanic navigation of the India companies
• Cartography as a mathematical discipline
• A Eurocentric view of the world, owing to the distortion of high latitudes
• The atlas as a publishing genre (Mercator coined the term in 1595)

Built on

• Map projection with coordinates (Ptolemy's Geography)c. 150 CE
• Portolan chartc. 1290
• Copperplate engravingc. 1430-1450
• Terrestrial globe1492
• Mathematical description of the rhumb line1537
• Rhumb line (loxodrome) (Pedro Nunes)1537
• Portolan charts
• Magnetic compass

Made possible

• Ortelius's Theatrum Orbis Terrarum (first modern atlas)1570
• Mercator's Atlas (the name "atlas" for a map collection)1595
• Mathematical construction of the Mercator chart (Edward Wright)1599
• Transverse Mercator projection (Gauss-Krüger) and the UTM system1822 (Gauss); 1912 (Krüger); 1947 (UTM)
• Van der Grinten projection1898
• Printed nautical charts
• Edward Wright's tables of meridional parts (1599)
• Ortelius and Blaeu's atlases

Links