Gerard Mercator's Revelation

chapter 5 Of Grids and Divine Mystery: Gerard Mercator’s Revelation

Lee Palmer Wandel

Construed within the history of cartography as a major step in the develop- ment of mathematical calculation,1 Gerard Mercator’s maps have been viewed through the lens of modern notions of cartographic ‘accuracy’, foremost calculations of longitude and latitude and the representation of land and sea those calculations engender. In this, their fate is not unlike the images of Samuel Dirksz van Hoogstraten, Pieter Janz. Saenredam, and Johannes Vermeer, long judged according to the norm of linear perspective, which Celeste Brusati has so illumined.2 Mercator shared with their work not least, Brusati’s formulation, ‘additive composites of aspects’. His maps have also been severed from their own material context. Mercator offered glosses for the beholders of his maps, that they might, with eyes informed, discern what uninformed eyes could not. To read his maps in this way, let us begin first with an archeology of three terms – descriptio,3 projection, and atlas – the first and last of which Mercator himself used to name what he was seeking to do.

1 The best general study of Mercator remains Averdunck H. – Müller-Reinhard J., Gerhard Mercator und die Geographen unter seinen Nachkommen, Ergänzungsheft Nr. 182 zu “Petermann’s Mitteilungen” (Gotha: 1914). For a list of all his maps and their relevant bibli- ographies, see Karrow, Jr. R.W., “Gerard Mercator”, Mapmakers of the Sixteenth Century and Their Maps (Chicago: 1993) 376–406. On Mercator’s place in the history of projection, see Snyder J.P., Flattening the Earth: Two Thousand Years of Map Projections (Chicago: 1993), es- pecially Ch. 1; idem, “Map Projections in the Renaissance”, in Woodward D. (ed.), The History of Cartography vol. III: Cartography in the Renaissance, Part I (Chicago and London: 2007) 365–381. 2 ‘[…] the traditions of perspective theory and practice favoured in the Netherlands accom- modate an understanding of pictures as additive composites of aspects; they neither pre- clude nor presuppose the unified prospect usually associated with Renaissance models of linear perspective and pictorial composition’, Brusati C., “Perspectives in Flux: Viewing Dutch Pictures in Real Time”, Art History 5 (2012) 912. 3 In preserving the Latin, I wish here, as throughout this essay, to recover connotations, reso- nances of meaning, that are lost when translated into modern English.

Figure 5.1 Gerard Mercator, Cartouche from Nova et aucta orbis terrae descriptio [New and Augmented Description of the World] (1569), in Meer S. de (ed.), Atlas van de Wereld: De wereldkaart van Gerard Mercator uit 1569 (Zutphen, Wallburg Pers: 2011) n.p.

1 Descriptio

In 1569, in one of the larger of the cartouches [Fig. 5.1], on what has come to be called his world map, Mercator set forth what had guided its making:

In making this [orbis descriptione] we have had three cares. First, to extend the surface of the sphere on a plane, so that the sit- ing of locations corresponds as much in true direction and distance as in longitude and latitude as in relationship to one another; as well that the [ figurae] of regions appearing on the sphere, insofar as it is possible, be preserved. Towards this [end] this work sets meridians to parallels in a new relationship.4

4 ‘[…] in hac orbis descriptione tria nobis curae fuerunt. Primum sphaerae superficiem ita in planum extendere ut situs locorum tam secundum directionem distantiamque veram quam secundum longitudinem latitudinumque debitam undequaque inter se correspon- deant, ac regionum figurae in sphera apparentes, quatenus fieri potest, serventur, ad quod