We were walking through the New Forest when we came across a
sign warning of unexploded ordnance. “Is
that why the Ordnance Survey is called the Ordnance Survey?” my friend
asked. “Is it something to do with the
military?” It seemed plausible, though I
didn’t know for sure. Despite being a
keen walker with an ever-growing collection of Ordnance Survey maps, I knew
very little about the origins of the organisation itself. Nor was I particularly aware of the general history
of cartography, despite being a life-long lover of maps (rolled up somewhere in my
parents’ loft is a highly detailed chart of the stream running through the
valley where I grew up). “Now there’s an
interesting topic for a blog,” I mused.
So here it is. A blog
on the history of mapmaking. A full
history would probably fill several volumes, so I have regrettably reduced it to a (very)
swift journey through the highlights in the fascinating story of cartography.
Early History
The earliest known maps were of the stars, rather than the
earth. Dots on the walls of the Lascaux caves
in southern France dating from 16,500 BC map out part of the night sky and the
Cuevas de El Castillo in Spain contain a dot map of the Corona Borealis
constellation dating from 12,000 BC.
The oldest known maps of the earth, however, are those preserved on Babylonian clay tablets, dating from around 2,300 BC. Early maps covered small, local areas and
were more artistic than accurate, since they were expensive and owning them a
sign of status. Although the Babylonians produced the
earliest known map of the 'world', it is far from accurate, deliberately
excluding the Persians and the Egyptians, and depicting the world as a
circular area of land surrounded by water.
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| Part of the Turin Papyrus Map |
Other examples of early maps include silk maps from China
and the Turin Papyrus Map, made by the Ancient Egyptians and believed to date
from around 1160 BC. Interestingly, it is thought to be the first map to show topographical detail,
depicting the mountains east of the Nile where gold and silver were mined. Trade routes are labelled in hieroglyphics
and the map also contains accurate geological detail.
Ptolemy
The Greeks and Romans, masters of invention, continued to
refine the art of mapmaking. This all
culminated with the work of the Greco-Egyptian scholar Claudius Ptolemaeus,
known in English as Ptolemy. Ptolemy
published the important work Geographia
(Geography) in about 150 AD, which contained thousands of references and maps
of different parts of the world. He
also, significantly, included lines of longitude and latitude. This system revolutionised European
geographic thinking, by imposing mathematical rules on the composition of maps. Ptolemy's work continued to influence Islamic and
European map makers well into the Renaissance period. It was Ptolemy’s calculations regarding the
circumference of the globe that led Christopher Columbus to set off on his
historic voyage, but Ptolemy wasn’t infallible and the figures were somewhat underestimated. It’s possible that Columbus wouldn’t have set
off if he had known the true figures, and that history would have taken a
remarkably different course!
China
The Greeks and Romans were not the only ones producing
maps. Chinese mathematicians and
cartographers were also developing mapping techniques. Pei Xiu (224–271) has been called the 'Chinese
Ptolemy' and is credited with influential work on the development of scale in
maps, having noticed the inaccuracies in distance on early Chinese maps. Pei also developed the work of earlier
Chinese cartographers on using gridlines on maps.
The Middle Ages
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| Al-Idrisi's Map of the World |
Few improvements were made in mapping during the Middle Ages
in Europe. Like all written material
during this period, the majority of maps were made in monasteries and religious
beliefs dominated their production, placing Jerusalem in the centre of world
maps. The maps also tended to include highly decorative religious imagery.
In contrast, Islamic cartography during this period was
taking advantage of knowledge gained by explorers and merchants travelling
across the Muslim world, from Spain to India, Africa, China and Russia. Al-Idrisi, an Arab scholar in the court of
King Roger II of Sicily, produced many brilliant ‘world’ maps and geographic
works in the mid-12th century, including the pleasingly titled ‘The
Amusement of Him Who Desires to Traverse the Earth’.
Renaissance
The printing press brought maps to a far wider audience by
the end of the 15th century and they were no longer dominated by
religious agendas. The accompanying thirst for
knowledge that characterised the Renaissance period drove the desire for the
improvement in mapping, as well as further exploration of the wider world. The first whole-world maps began to appear in
the early 16th century, following voyages by Columbus and others to the New
World, with the first world map generally accredited to the German cartographer Martin Waldseemüller. Produced in 1507, Waldseemüller’s map drew on
Ptolemy’s work and was the first map to use the name America for the New World
Modern Maps
From the 16th century onwards, maps gradually became
more detailed and more accurate. Like
many inventions, the greatest improvements were driven by military needs. As wars increased in their numbers and scale, precise information was needed about territory. Alongside this, the growth and development of transport, in
particular the railways in the 19th century, necessitated accurate
maps of large areas as well. It was during
World War I that the use of aerial photography, for the initial purpose of mapping the trenches and frontlines, made its first impact on improving standards of mapping.
Ordnance Survey
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| A Ramsden Theodolite |
As predicted, the Ordnance Survey was developed for
military needs. Rebellion in Scotland
and a war against France prompted George II to commission a military survey of
the Scottish Highlands in 1746. By 1790,
Europe was in turmoil and there were fears that the French Revolution would spread
across the Channel. The Government
therefore ordered the Defence Ministry (then the Board of Ordnance) to begin a
survey of England’s southern coast. To
aid with this, the Board purchased a huge new Ramsden theodolite. Jesse Ramsden’s innovative surveying instruments
consisted of a mounted telescope which rotated to give the angle of view and
were very accurate. Only a few were ever built.
The first one-inch map of Kent was produced in 1801, followed
by a similar map of Essex. Within 20 years, about a third of England and Wales had been
mapped in one-inch scale. Major Thomas
Colby (Director General of the Ordnance Survey) walked 586 miles in 22 days on
a reconnaissance in 1819. In 1824 Parliament
asked Colby and his staff to produce a 6-inch to the mile survey of Ireland. Colby was a very
hands-on boss, travelling with his staff to set up camps and bringing them plum puddings
on the top of mountains! The first Irish
maps appeared in the mid-1830s.
The Tithe Commutation Act of 1836, alongside the demands of
railway engineers, prompted calls for 6-inch surveys of England and Wales,
which was agreed by the Treasury in 1840.
In 1841, following a fire at the Grand Storehouse of the Tower of
London, the Survey moved their offices to Southampton. During the 1860s, Major-General Sir Henry James used his
directorship of the Survey to exploit the new science of photography to cheaply
and quickly enlarge maps, and he designed an elaborate glass studio at
Southampton for processing photographic plates. By 1895, a twenty-five inch survey of Britain was complete.
Following the disruption of the First World
War, it became apparent that the Ordnance Survey’s maps were woefully outdated. In 1935 the Davidson Committee was
established to review Ordnance Survey's future. That same year, the far-sighted
new Director General, Major-General Malcolm MacLeod, launched the re-triangulation
of Great Britain. Surveyors began the
mammoth task of building concrete triangulation points on remote hilltops
across Britain. The re-triangulation was
finally completed after the Second World War, utilising new methods, such as improvements in aerial surveying and up-to-date drawing
techniques.
The Davidson Committee's final report set Ordnance Survey on
course to face the challenges of the 21st century. The National Grid reference system was introduced,
using the metre as its measurement. An experimental new 1:25,000 scale map was
launched. The digitisation of maps
began in 1973. By this point, the organisation itself was changing too. In 1974 the position of Ordnance Survey
Director General became a civilian post, and in 1983 it became a wholly
civilian organisation.
Further change took place in 1999 when the agency became a
government trading fund and as of 1 April 2015 it has operated as a Government
owned limited company. The Ordnance Survey
digitised the last of some 230,000 maps in 1995, making Britain the first
country in the world to complete a programme of large-scale electronic mapping. It remains a world-leading mapmaking
organisation, regularly surveying all 243,241 square kilometres of the British
Isles and making thousands of updates on a daily basis.
Read more about the history of the Ordnance Survey here.
Maps of the Future
Satellite technology and GIS are improving the accuracy of
maps all the time. Mass publication has
made them cheaper and street maps are now freely available on the
internet. This has had an impact on
organisations such as the Ordnance Survey, which has sometimes struggled to stay
up to speed with the changing face of cartography.
However, even today’s maps are not completely accurate
representations of the real world. As with
anything man-made, all measurements are subject to human error. Aerial photographs and satellite images show
only certain portions of the light spectrum.
Maps portray features using symbolic styles defined by classification
schemes. All maps are made according to
certain basic assumptions, such as sea level measurements, which are not always
verifiable.
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