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Mapping the World by Beau RiffenburghMapping the World: The Story of Cartography, Beau Riffenburgh (Carlton Books 2011, 2014)

A good map is like a swan on a river. Beneath the elegance there is a lot of effort. This book is about that effort: all the millennia of research and refinement that have gone into perfecting maps. Not that any map can be perfect. As Beau Riffenburgh explains here, there are always choices to be made: what do you put in, what do you leave out? And how do you represent spherical geometry on flat paper?

The Flemish cartographer Gerardus Mercator came up with one famous answer to that question:

Mercartor’s major achievement came in 1569 with a new projection that represented a breakthrough in nautical cartography. Since known as the Mercator projection, it is cylindrical-like, with the meridians as equally spaced parallel lines and the lines of latitude as parallel, horizontal lines, which are spaced further apart as their distance from the equator increases. This projection is uniquely suited to navigation because a line of constant true bearing allows a navigator to plot a straight-line course. However, this projection grossly distorts geographical regions in high latitudes – thus Greenland is shown larger than South America, although it is actually less than one-eighth of the size. (“Cosmographies and the Development of Projection”, pg. 51)

So the map looks wrong, but leads right. So does the famous map of the London Underground, which ignores true distances and bearings: the designer Harry Beck made it look like an “electrical circuit, with straight lines and the inclusion of only one feature above ground – the Thames” (“Mapping for the Masses”, pg. 143). Maps are about abstraction: they condense and confine what people find interesting or important about the real world.

So minds mould maps and in writing about maps, Riffenburgh is also writing about culture and politics. About art too, because maps can be very beautiful things, sometimes deliberately, sometimes incidentally. Above all, however, he’s writing about mathematics. What was implicit from the beginning – the importance of maths in mapping – became more and more explicit, as he describes in the chapter “Men, Measurements and Mechanisms” (pp. 70-3). The men are drawn from the world’s most evil and energetic group: white Europeans. Galileo, Newton and Huygens are three of them: as they contributed to maths and science, they contributed to cartography.

Another man is the Yorkshire watchmaker John Harrison (1693-1776), the hero of Dava Sobel’s Longitude (1995). He was a remarkable personality and looks it in the portrait here: proud, determined and self-possessed. He needed all those qualities to get his due. He invented a chronometer that kept accurate time on long voyages and enabled navigators to determine longitude, but British officialdom “made him wait years for all of his prize-money” (pg. 73).

Elsewhere the names are obscurer and the stories sometimes sadder:

In the history of cartography, few individuals stand out for their work in so many geographical regions and aspects of science as James Rennell. Born in Devon in 1742, Rennell went to sea at the age of 14, learned maritime surveying and then, at the end of the Seven Years’ War, received a commission in the Bengal Army as an engineer. … Equipped with quadrant, compass and chain, Rennell began a thorough and scientific survey of [Bengal’s] major river systems, roads, plains, jungles, mangrove forests and mountains. (“James Rennell: Mapping India, Africa and Ocean Currents”, pg. 86)

However, he “never fully recovered from a severe wound received in an ambush” and retired to London to produce his “masterpiece – A Map of Hindoostan, or the Mogul Empire” (1782/1788). But en route to England, he had an “extended stay in Southern Africa” and developed an interest in ocean currents. So he became a pioneering hydrographer too: his posthumous An Investigation of Currents of the Atlantic Ocean (1832) “is often considered to form the historical basis of the study of currents” (pg. 89).

Later in the century, the German August Petermann worked for the Royal Geographical Society and was appointed “Physical Geographer Royal” by Queen Victoria. His assistant John Bartholomew said “no one has done more than he to advance modern cartography”, but Petermann committed suicide in 1878 after returning to Germany (“Maps reach a wider audience”, pg. 132).

Nietzsche would not have approved. But I think he would have applauded this:

Perhaps the most remarkable nautical drawings of all, considering the conditions under which they were produced, were those of William Bligh, captain of the British ship HMAV [His Majesty’s Armed Vessel] Bounty in 1789. Following the infamous mutiny, Bligh and 18 loyal seamen were set adrift in the ship’s launch. During the next 47 days, Bligh navigated approximately 3,600 nautical miles (6,660 km) to Timor, with only one stop. Throughout the journey, which is considered one of the most remarkable accomplishments in the history of open-boat travel, Bligh kept a detailed log and made sketches of his course. (“Mapping Australia and the Pacific”, pg. 77)

His chart is reproduced here. Using anecdotes like that with serious analysis and intellectual history, Riffenburgh tells the story of cartography from Mesopotamia and before to the moon and beyond. The story of maps is the story of man: even pre-literate societies like the ancient Polynesians have used maps to record the sea and its currents. In Europe, maps have reflected every advance in technology, like printing and photography. But as they’ve responded to technology, they’ve altered the way we see and interact with reality. When you look at a map, there’s a whole world of exploration, endeavour and ingenuity just beyond its margins. Mapping the World is about that world: the margins of mapness without which the maps themselves would not exist. It’s a book to stimulate the mind and delight the eye.

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