Benjamin Høyer: Cartography

Introduction

Ever since people started to venture beyond the nearest few villages we have people drawing picture to describe the journey. Right from the earliest maps found on cave walls in France showing nearby villages, people have been able to venture into new areas, based on maps produced by earlier travellers. This represents one use of maps, which is the use we most often associate with maps today. However, historically maps have seen great use as political and religious tools, acting to confirm people's idea of the world, and their position at its centre.

Diagram of the world according to the ancient Chinese. The centre represents the imperial palace.
Reading outwards, we eventually reach the lands of "savages who have no culture at all".
Art & Cartography, David Woodward (University of Chicago Press, 1987) p25.

Later in the middle ages, maps began to be a great political power tool. To have a map of enemy territory was to be able to plan a war. In fact mediaeval cartographers , such as Mercator, were among the best paid craftsmen of their day. Then, maps were not needed by the common map. Their cost was high, and they had little use for them. In modern time haps have become commonplace. Classrooms the world over display a map of the world on their wall, and from these maps children build a sense of the world around them early on. Little thought is ever given to what the map actually displays, and the shapes and areas (usually on a Mercator projection) are taken to be the way things really are. Even comparing a small range of map projections, we see a huge variation in how the world looks. We are immediately reminded that the correct interpretation of a map is about as important as the map itself.

This project aims to introduce non-mathematicians with an interest in map projections to some of the techniques employed in map making. Starting from the simplest concepts, no prior knowledge is required beyond simple trigonometry. More complicated projection techniques will be mentioned, but the focus will remain on illustrating the underlying techniques, and the knock-on effects on the finished projection.