Difference between revisions of "Mercator"

From ICA Map Projections
Jump to: navigation, search
m (clarifying Pedro Nunes contribution)
Line 37: Line 37:
 
*1511: Erhard Etzlaub (Nuremburg) creates maps using an accurate Mercator projection. He records nothing of his method.
 
*1511: Erhard Etzlaub (Nuremburg) creates maps using an accurate Mercator projection. He records nothing of his method.
 
*1537: Pedro Nunes (Portugal) describes the [[rhumb]].
 
*1537: Pedro Nunes (Portugal) describes the [[rhumb]].
*ca. 1566: Nunes describes for the first time a way to approximate a [[large-scale]] projection that keeps rhumbs straight, but does not construct any maps based on it. Whether he realized the principle could be generalized to a [[small-scale]] projection remains unclear.
+
*1537: Nunes suggests the construction of a world chart composed of many large-scale sheets, each of them in the equirectangular projection centred at its middle parallel. Two solutions were possible: either use the same principal scale for the whole chart, keeping constant the distance between parallels; or conserve the distance between meridians in order to keep the graphical continuity between adjacent sheets. The second solution is, of course, only a little step from the Mercator projection. However, this development was probably strange to the ideas of the mathematician, whose main intention was to avoid the inconsistencies of the existing small-scale charts with a system of representation that could be considered, for practical purposes, conformal and with constant scale.
 
*1569: Gerardus Mercator (Flanders; probably christened Gerhard Kremer) produces a small-scale map based on the loxodromic principle, and promotes it for the purpose of navigation. His method of construction remains unknown.
 
*1569: Gerardus Mercator (Flanders; probably christened Gerhard Kremer) produces a small-scale map based on the loxodromic principle, and promotes it for the purpose of navigation. His method of construction remains unknown.
 
*1599: Edward Wright (London) describes the exact mathematics of the spherical Mercator projection for the first time, although his description amounts to an infinite series rather than the modern, closed form obtained from the calculus.
 
*1599: Edward Wright (London) describes the exact mathematics of the spherical Mercator projection for the first time, although his description amounts to an infinite series rather than the modern, closed form obtained from the calculus.

Revision as of 19:42, 17 April 2006

Projection name: Mercator

English Français Deutsch 日本語 Русский Español Polski Português
Mercator メルカートル Поперечно-цилиндрическая проекция Меркатора


Chronology of projection development

  • 1511: Erhard Etzlaub (Nuremburg) creates maps using an accurate Mercator projection. He records nothing of his method.
  • 1537: Pedro Nunes (Portugal) describes the rhumb.
  • 1537: Nunes suggests the construction of a world chart composed of many large-scale sheets, each of them in the equirectangular projection centred at its middle parallel. Two solutions were possible: either use the same principal scale for the whole chart, keeping constant the distance between parallels; or conserve the distance between meridians in order to keep the graphical continuity between adjacent sheets. The second solution is, of course, only a little step from the Mercator projection. However, this development was probably strange to the ideas of the mathematician, whose main intention was to avoid the inconsistencies of the existing small-scale charts with a system of representation that could be considered, for practical purposes, conformal and with constant scale.
  • 1569: Gerardus Mercator (Flanders; probably christened Gerhard Kremer) produces a small-scale map based on the loxodromic principle, and promotes it for the purpose of navigation. His method of construction remains unknown.
  • 1599: Edward Wright (London) describes the exact mathematics of the spherical Mercator projection for the first time, although his description amounts to an infinite series rather than the modern, closed form obtained from the calculus.
  • ca. 1600: Thomas Harriot (London), in unpublished manuscripts, develops the modern logarithmic form of the projection.
  • 1610: Wright publishes accurate tables for the construction of the Mercator projection, unaware of Harriot’s unpublished work.
  • 1645: Henry Bond (London) publishes the modern logarithmic form of the projection in Norwood’s Epitome of Navigation, also unaware of Harriot’s unpublished work.