Maps and views blog

Cartographic perspectives from our Map Librarians

Introduction

Our earliest map appears on a coin made in the Roman Empire and our latest appears as pixels on a computer screen. In between we have the most complete set of Ordnance Survey maps of Great Britain, the grand collection of an 18th-century king, secret maps made by the Soviet army as well as the British government, and a book that stands taller than the average person. Read more

23 June 2020

Maps and photography: a brief history, part 2

The previous part of this article discussed the introduction of photography into maps and mapmaking over the first hundred years after its invention in the 1830s. Photography was initially used to complement information found on the map, by recording topographical views or objects of antiquity, and it was incorporated into the map production process from the 1850s. In this early period photographers also began to capture the work of survey teams in the field. Soldiers in the British Royal Engineers were specially trained in the use of cameras for this purpose. This group photo from circa 1860 was taken by one such soldier-photographer, and shows colleagues posing in a cutting cleared through the forest to enable survey work along the border between the United States and Canada.

Photograph of Royal Engineers Survey Team circa 1860

Cutting on the 49th Parallel, on the Right Bank of the Mooyie River Looking West, c.1860. Image courtesy Victoria & Albert Museum, Museum No. 40090.

Cameras were also employed to record advances in cartographic technology and instrumentation. The following scenes were set up to demonstrate use of the latest levelling instruments by staff at the Survey of India in 1909. Beyond this original purpose, the first image also illustrates the colonial hierarchy in the division of labour that was based on race.

Photograph of Survey of India staff with levelling instrument 1909

Photograph of Survey of India staff with levelling staves 1909

Observer with Cylindrical Level and Recorder (above) and General Walker’s Staves Erected upon Pegs (below), in Account of the Operations of the Great Trigonometrical Survey of India, Vol 19, Levelling of precision in India, 1910. BL IOR/V/19/20.

Another later image demonstrates the same division of labour in Africa amongst members of the Anglo-Belgian Congo-Zambesi Boundary Commission, as European surveyors take observations from a trig point around 1930. A contemporary account of the survey published in The Geographical Journal highlights the pressure the Commission was under from the two European administrations to agree and demarcate this African boundary quickly, so that valuable mining rights could be settled between them.

Photograph of Congo-Zambesi Boundary Commission 1927-34

Observing from Trig. Point, Congo-Zambesi Boundary Commission, 1927-34. BL shelfmark not yet allocated.

After the First World War there was a drive to realise the potential of aerial photography in new fields of geographical and archaeological analysis away from the battlefield. In 1919 G.A. Beazley published an article entitled Air Photography in Archaeology, in which he described wartime aerial survey work carried out around Samarra in modern-day Iraq. The survey had revealed the layout of an ancient city, details of which were transferred to the military map, below, though they were evident only from the air.

Map of Samarra 1919

Detail of Central Quarter of the City with Public Gardens, in The Geographical Journal Vol. 53, No. 5 (May, 1919), pp. 330-335. BL Maps 159. [Detail also appears on ‘Tigris Corps’ map sheet T.C. 109, held at BL Maps C.14.s.]

Another pioneer of aerial archaeology was O.G.S. Crawford, who was appointed the first archaeological officer at the Ordnance Survey in 1920. He used air photographs made by the RAF to measure the length of the Avenue at Stonehenge, and later joined with Alexander Keiller to make an aerial survey of archaeological sites in several British counties. Together they published Wessex from the Air in 1928.

Air photograph of Hambledon Hill in Wessex 1928

Hambledon Hill, in Wessex from the Air, 1928. BL General Reference Collection 7709.t.13. Image courtesy Digital Library of India.

With the introduction of black and white infra-red photographic film in 1931, a new kind of geographical analysis became possible. Infra-red film responds to different wavelengths of light from the panchromatic type, and was useful in indicating high tide lines and different types of vegetation. The glass slide below shows an infra-red image from the 1930s, in which bare hills appear dark and sharply distinguished from the characteristically bright areas of cultivation at their feet. The water in the meandering river also shows up black.

Early infra-red air photograph 1930s

Early infra-red film slide, location unknown, 1930s. BL shelfmark not yet allocated.

With the outbreak of the Second World War the use of infra-red film was amongst a number of techniques trialled with aerial photography to map the gradients of enemy-held beaches. In the end, the most successful method used air photographs taken with panchromatic film to determine the shape of the seabed by studying the shapes and velocities of wave patterns as they came to shore.

Air photographs of waves 1940s

W.W. Williams, The Determination of Gradients on Enemy-Held Beaches, in The Geographical Journal Vol. 109, No. 1/3 (Jan. - Mar., 1947), pp. 76-90. BL Maps 159.

This crucial element of wartime invasion planning appears in the following beach map of an island off the coast of modern-day Myanmar. The diagrams in red, on the right, were derived from air photographs and show the beach gradients at different numbered points on the map.

Beach gradient map of island in Burma 1944

Detail of Hind 603 beach map [Burma], 1944. BL Maps 13496.

Photography fulfilled other roles in wartime invasion planning. During the Second World War German forces created volumes of geographical intelligence by country, in preparation for the invasion of foreign nations in Europe, North Africa and the Middle East. These volumes included photographs that complemented the information found on maps by giving a visual impression of the lie of the land, and by providing additional geographical intelligence. Pictures illustrating local geomorphology appear alongside images of industrial buildings, harbours and fortifications.

In the volume dedicated to the South Coast of England a number of what appear to be pre-war tourist postcards have been reproduced. The example below shows location 255 on the map of the Isle of White that follows. The accompanying text explains its inclusion - ‘Narrow sandy beach in front of the bank fortification, is exposed at low tide.’

Photograph of beach near Ryde reproduced 1940

Map of Ryde on Isle of White 1940

Militärgeographische Angaben über England, 1940. BL Maps 47.g.13.

Advances in aerial photogrammetry had continued between the wars with the invention of multiplex instruments in Italy and Germany in 1930, which allowed a single operator to map large areas quickly from small scale air photographs. In the United States the technique was adopted by USGS, the national mapping agency, and was widely used to map agricultural areas under New Deal public works projects, so that by the start of the Second World War a large number of trained photogrammetrists was available for the American war effort.

Many of these photogrammetrists were put to work creating photomaps of islands in the South-East Asian Theatre, producing innovative sheets that consisted of a conventional line map on one side and a rectified photomap on the reverse.

Photomap of Iloilo Town in Philippines 1944

Iloilo Town, Central Philippines 1:25,000 photomap, 1944. BL Maps Y.2602. Image courtesy University of Wisconsin-Milwaukee Libraries.

Similar advances had been made in large-scale aerial photogrammetry with the invention of the slotted template method in the United States in 1936. This was a development of radial line plotting techniques first promoted by the British Air Survey Committee in the 1920s, and provided a method of adjusting and correlating large numbers of overlapping air photographs.

One of the most intensive periods of large-scale aerial survey activity during the war came with the secret preparation of the so-called ‘Benson’ series of maps, named after the RAF station in Oxfordshire from which many of the survey and reconnaissance flights departed during 1942–43. The series was completed in advance of the D-Day landings in 1944, and features an overprint showing German defences along the Normandy coast of France. The British Library is currently conserving a representative set of materials used in the compilation of these secret maps, which will be made available at shelfmark BL Maps Y.4169. The material includes a US Army report that compares the accuracy of a sheet made by the multiplex method with one made by the slotted template technique.

Benson Series map of Creully in Normandy 1944

Benson Series, Creully sheet, 1944. BL Maps MOD GSGS 4347 [Defence O/P].

The final chapter will lead this brief survey up to the present day...

Nick Dykes

18 June 2020

British Library map leads to a Gibraltar archaeological discovery

A guest post by Prof. Jason Dittmer,  UCL Department of Geography

Recently the British Library map collection has been central in the discovery of a long-lost curtain wall in the Northern Defences of Gibraltar. How is it that a single map in the archives at St Pancras has impacted historical conservation work at the entrance to the Mediterranean?

Gibraltar is a British Overseas Territory, taken from Spain in 1704 and ceded in the Treaty of Utrecht of 1713. Astride the only natural entrance to the Mediterranean Sea, and dominated by its eponymous Rock, Gibraltar gave the British a good harbour and a perfect defensive position from which to protect the sea lanes upon which Pax Britannia would be built. Mounted on the cliffs of the famous Rock of Gibraltar and overlooking the only road into the rocky peninsula, the Northern Defences were built to maximize the natural advantages of the British fortress against Spanish and French attackers in the famed Great Siege (1779-1783) and in the Nineteenth and Twentieth Centuries. They were updated to protect the ‘Key to the Mediterranean’ from a hypothesized Nazi attack during World War 2, which would make use of tanks and paratroopers. After World War 2, however, the Northern Defences were abandoned by the British army, as Gibraltar burst its walls and transformed itself from a military fortress into a cosmopolitan European society. Recently, the Government of Gibraltar has sought to re-cover this heritage to make the most of its tiny (2.6 square mile) territory for Gibraltarians themselves.

I first came to Gibraltar to lead geography students from University College London on a political geography field class, studying the way past and present geopolitics came together in this geographically tiny but historically outsized territory. I quickly became fascinated with the location and began my own study of the cartographic representation of Gibraltar, using the tremendous resources of the British Library. The second time I taught the field class, I was introduced to Carl Viagas, the project manager of the multi-year effort to clean up and restore the Northern Defences. Carl cheerfully offered to take my students on a tour of the Northern Defences, which I had never seen. In doing so, he articulated their spatial logic and how he replicated that logic in order to dig out long-hidden elements of the defences from under about 5,000 tons of rubble and vegetation. The students loved it, and in Carl I sensed a fellow traveller in his love of the place’s geography. I offered to send him any particularly good maps of the Northern Defences that I came across which might help him advance the project.

Maps K.Top 72.47.2.b with wall
Detail of PLAN of the NORTH FRONT of GIBRALTAR by Charles O'Hara, 1756, with the location of Hanover Wall marked in red.

Back in London, I returned to the British Library and began searching through the map collection with renewed enthusiasm. As I scanned potentially useful maps I sent them to Carl. His replies: ‘Yeah, seen it.’ ‘Ah yes, a classic’. ‘A very nice one.’ Then, finally: ‘That’s brilliant mate! Never seen this one.’

Carl describes what happened next:

"Jason shared the same enthusiasm for this location and provided me with countless drawings, maps and data of the area. It was in one of these drawings where I noticed that a line of defences, even though not unique to this map, is referred to as the ‘Hanover Line’. Always keen in establishing links between Gibraltar and Germany this particular monument became a source of personal great interest.

Uncovering it would be a problem though as the area was difficult to access and there was no guarantee that there would be any remains even if the site was identified. I could not defend the expenditure of significant public funds on “possible” finds.

This suddenly changed when shuffling through a 1908 Ordnance Survey I was able to identify the lower end of Hanover Line, a line that I would have continued to ignore had it not been for my renewed interest and the new available information which Jason poured in my direction."

Detail of Maps KTop 72.49.2.b.tab showing the Hanover Wall
A detail of the map of Gibraltar showing the Hanover Wall

The original map in question, ‘PLAN of the NORTH FRONT of GIBRALTAR’ by Charles O’Hara (1756, from the Topographical Collection of George III or 'K.Top'), was an enclosure attached to a report from the Governor of Gibraltar about improvements to the Northern Defences that would be tested several decades later during the Great Siege. The map clearly indicated the location of the Hanover Wall, which had stretched from the Tower of Homage – the Moorish castle at the pinnacle of the defences – down to the Hanover Batteries lower down the Rock, but whose location had been lost. The Hanover Wall appears (under another name) on other maps at least as far back as 1627, when Spain held Gibraltar.

Locating the buried Hanover Wall
Locating the buried Hanover Wall (photo: Carl Vaigas)

Workers directed by Carl quickly found the remains of the wall, which remained intact, although fully submerged under dirt and foliage. The efforts of these men revealed the long-lost wall, a critical part of the Northern Defences which had been lost amidst the rapid changes in Gibraltar throughout the 20th Century.

The Hanover Wall revealed
The Hanover Wall revealed (photo: Carl Viagas)

Thanks to the map collection of the British Library, it is currently being excavated and integrated into Gibraltar’s existing heritage resources. The Deputy Chief Minister, Joseph Garcia, has confirmed the Government of Gibraltar’s commitment to the project: ‘Not only does this project address our continued responsibility and commitment to our heritage and environment, but it also shows the potential to increase the value of our tourist product and social demands for open areas’.

16 June 2020

Runnymede - a history in maps

Magna Carta, one of the world’s most significant legal documents, was 805 years old yesterday. The charter, which addressed the feud between the crown and rebel barons, was signed by King John on 15 June 1215 in the Thames meadow of Runnymede near Windsor.

https://commons.wikimedia.org/wiki/File:ABA-wyrdlight-815935.jpg
American Bar Association tribute to Magna Carta at Runnymede

Today this meadow is known as the ‘birthplace of modern democracy’ and steeped in history and significance. Yet the historic site of Runnymede makes only a limited appearance in historic maps. The issue is partly, of course, one of scale; it's not easy to show something as small as a single field in a map of Britain, or even a county map. But even then, important sites will find their way onto maps if they are significant enough. 

So what happened to Runnymede? It doesn’t appear on the Matthew Paris itinerary map of Britain produced only 35 years after the event. It doesn’t appear in any 16th or early 17th century printed county maps, and it is particularly strange for Runnymede not to appear in John Speed’s 1611-12 county map of Berkshire. Speed wasn’t so much a mapmaker as a historian and antiquarian following in the footsteps of his mentor William Camden in unearthing Britain’s early history. Speed’s atlas The Theatre of the Empire of Great Britaine was stuffed full of historical images and references, but there is no mention of Runnymede on the map or in the text.  (Speed's sources included manuscripts in the Library of Robert Cotton, now part of the British Library, which would acquire two of the four surviving copies of Magna Carta shortly after Speed’s death in 1629).

John Speed, Barkshire detail
Detail of John Speed's map of Berkshire, 1611-12 (around 1690)

The absence of Runnymede from Speed's map certainly doesn’t mean that Magna Carta was not important in the 17th century. On the contrary, the charter was extremely prominent, used and interpreted in public life. This may be the key to why Speed didn’t mention it: because it was wielded by opponents of Speed’s patron, King James I, as proof against the divine right of monarchs. The issue of divine right would ultimately lead to the execution of James's son Charles I in 1649.

Bowen kitchin
Detail from Thomas Kitchin, Berkshire, from the best authorities... c. 1747.

The continuing significance of Magna Carta did not transfer to its place of signing, which continued to be absent from 18th century maps such as the compendious Berkshire map from Bowen and Kitchin’s Large English Atlas from the late 1740s.

However, the establishment of a minimum ideal scale for maps - one inch to the mile - as set by the Society of Arts and their competition aimed at encouraging high quality county maps from 1759, provided the necessary level of detail for Runnymede to appear. It appears on Lindley and Crossley's large map of Surrey of 1793. And in the 2 inch to the mile drawing of 1811 by one of the early Ordnance Surveyors, Runny Meade is marked, as is Magna Charter Island. They are described with typical OS dryness, in the same way as every other island and meadow. 

https://commons.wikimedia.org/wiki/File:Ordnance_Survey_Drawings_-_Windsor_(OSD_153).jpg
Detail from an Ordnance Surveyor Drawing of part of Surrey, 1811 (Maps OSD 153)

It was only in the early 20th century that Runnymede acquired a distinct identity, when the requirement for a site-specific memorial to Magna Carta emerged. The National Trust acquired it in 1929, and from around that time it began to appear on maps which explicitly referenced its significance. It appeared particularly in pictorial maps and tourist maps, following the rise of mass tourism in Britain and from the United States. Runnymede became, like the surviving copies of the original charter, emblematic of keenly held 20th century principles of democracy and liberty.

MacDonald Gill
Detail from MacDonald Gill, Country bus services map - London and vicinity. London, 1928.
Bullock 1961
Detail from J.G. Bullock, Historical map of England and Wales, 1961.

There is certainly nothing unusual in Runnymede only acquiring significance many centuries after the event that made it significant occurred, just as there is nothing unusual in the principles contained in Magna Carta being modified to provide historical reassurance for successive eras. History is constantly being rewritten in order to fit the circumstances of the present. Objects such as charters, maps, even buildings and statues, are focal points for this shifting sea of history that doesn’t flow around them, but carries them along with it.

11 June 2020

Great Barrier Reef ‘discovery’

Exactly 250 years ago today Captain James Cook ‘discovered’ the Great Barrier Reef the hard way when his ship Endeavour ran into it on the 11th June 1770 and nearly sank. The Reef is located in the Coral Sea off the north-eastern coast of Australia and stretches some 2,300 km (over 1,400 miles). This unique marine ecosystem is the world’s largest structure made of living organisms which UNESCO declared a protected World Heritage Site in 1981.

Add MS 15500  f 1 detail1

Detail from Part of the southern Hemispher[e] showing the Resolutions track through the Pacific and southern ocean’ by Joseph Gilbert taken during Captain James Cook's voyage in the Resolution through the Pacific and Southern Oceans (1772-1775) showing the coast of Australia with the Great Barrier Reef depicted as unconnected shoals and small islands. Add MS 15500, f 1

Maps and charts drawn by Captain James Cook can be found among the British Library’s collections as well as other documents related to his voyages, including Endeavour’s log book. According to the captain’s log on Monday 11 June 1770 the conditions were good with ‘fine weather and smooth sea’. Cook was aware of underwater obstacles and was cautiously navigating through the maze of rocks and shoals recording depth soundings regularly, when suddenly just before 11pm the ship collided with a rock (which he later realised was a bank of coral).

Add MS 8959  f.125

Detail from the Captain’s log dated 11th June 1770 reporting the incident (folio 125r). Log-book of the Endeavour, Lieutenant James Cook, Commander,  from May 1768 to July 1771, Add MS 8959, f. 125r

After 23 long hours of desperate attempts to re-float the ship (including throwing cannons, iron and stone ballast, casks, even oil jars, overboard to lighten the vessel) Cook and his crew finally managed to get Endeavour off the reef. They made their way to shore where on the banks of the river at the site of modern Cooktown repairs were carried out.

Add_ms_7085_39

 Add_ms_7085_39 detail
A chart of part of the sea coast of New South Wales, on the east coast of New Holland, from Cape Tribulation to Endeavour Straits; drawn by Lieut. James Cook, 1770. Second image: detail showing the locations of the incident and a makeshift harbour on the Endeavours River. Add MS 7085, f 39

Cook never fully realised the vastness of the Great Barrier Reef, nevertheless the maps and charts compiled during his voyages were extremely detailed and provided the basis for further exploration of the Australian coastal waters. They were gradually improved upon through painstaking surveys carried out over the following years by various Admiralty captains and naval officers. A series of navigational charts produced by the Hydrographic Office covering the region were constantly updated and reissued with corrections well into the 20th century. Sir David Attenborough recalls using Cook’s charts as late as the 1950s when sailing parts of the Great Barrier Reef.

10491.e.18 p20

Chart of the Northern part of the Great Barrier Reef including Torres Strait & yt adjacent coast of New Guinea published in A sketch of the physical structure of Australia..., 1850. 10491.e.18

Coral Sea and Great Barrier Reefs

Coral Sea and Great Barrier Reefs ... from the surveys of Captains Flinders, P.P. King, Blackwood, Owen Stanley and Yule, 1802-50 ; the outer detached reefs, and line of Great Barrier Reefs from Captain Denham, R.N. 1858-60 compiled in the Hydrographic Office by Mr. F.J. Evans, 1860. Maps SEC.14.(2763, 2764.) Image courtesy of the National Library of Australia

The Great Barrier Reef is home to the richest biodiversity on Earth providing feeding grounds, nursery areas and living space to countless marine species. The Reef is incredibly important not only to the oceanic life, it also helps to shield coastal ecosystems by reducing erosion and absorbing wave energy during storms and hurricanes. In recent years alarming reports about the impact that climate change has had on the Reef highlight issues such as rising sea temperatures, pollution and bleaching factors contributing to coral damage, ultimately leading to gradual languishment and death of portions of the Reef.

Maps play an incredibly important role in environmental projects and conservation initiatives which rely on the most up to date data and work closely with mapping agencies surveying the ocean floor which help scientists to understand and address the issues posed by the challenges climate change.

09 June 2020

Maps and photography: a brief history, part 1

Since the invention of photography in the late 1830s, the camera’s ability to record and document its surroundings has made it a natural partner of the mapmaker. From the beginning, photographers recorded landscapes in the manner of artists’ topographical views, providing ‘scientific’ perspectives to complement the view from the map. Subsequently, photographs became integral to the mapmaking process – by capturing data that is incorporated into maps, or by transformation into maps themselves. Cameras also recorded the methods, tools and people employed in making maps; and in the world of art, photographers showed the influence of cartography’s ordered aesthetic.

Aerial photograph by Robert Petschow

A Crossing of the Single Track Sandau-Schonhausen Railway Line and the Main Berlin-Hannover Line, by Robert Petschow, in Das Land der Deutschen, 1933. BL General Reference Collection J/X.802/4246.

With the help of items held in the British Library collection, this first of three articles provides a brief introduction to the varied uses of photography in and around mapping up to the 1930s.

In 1855 photographer and army officer Linnaeus Tripe was included amongst the members of a diplomatic mission sent from the Government of India to Upper Burma. Here he fulfilled instructions to record the country and the people of the region by making over 200 architectural studies and landscape views. Many of his photographs appeared in the official published account of the mission (BL General Reference Collection 2354.h.7.), where they accompanied sketches, watercolours and maps to form an important record of the region that was little known by outsiders at the time.

Photograph of Shwe Dagon Pagoda, Burma by Linnaeus Tripe

No. 107. Rangoon. Shwe Dagon Pagoda, by Linnaeus Tripe, 1855. BL Photo 61/1(107).

In the same period, photographers were employed for the first time by the British Ordnance Survey. Colonel Sir Henry James, Superintendent of the OS, introduced photography into the process of map production in 1855, and encouraged a role for photography in the recording of objects of antiquity, which he saw as integral to the wider work of survey and mapping. In 1864 he ordered the Survey of Jerusalem, where surveyor-photographer James McDonald of the Royal Engineers made 87 photographs showing various views of the Holy City. The images were published in their own separate volume of the official report (BL Maps 30.e.19.).

Photograph of the Church of the Holy Sepulchre, Jerusalem, by James McDonald

West entrance to the Church of the Holy Sepulchre, Jerusalem, by James McDonald, 1864. BL AdF72/27947 (27b).

The first recorded photographs taken from the air also date from this early period. In 1858 French photographer Nadar took pictures of Paris from a hot air balloon tethered near the Arc de Triomphe. Oblique views obtained in this way from balloons or from cameras tethered to kites were sometimes labelled to identify streets and landmarks, arguably making these the earliest photomaps, but of higher value to cartographers were images taken from cameras that pointed vertically down to earth. Cecil Victor Shadbolt made the first such photograph of the UK still in existence, from a hot air balloon over Stamford Hill, London on 29 May 1882.

Aerial photograph by Cecil Victor Shadbolt

An aerial view showing Stonebridge Road, Stamford Hill, and Seven Sisters Curve, part of the Tottenham and Hampstead Junction Railway, taken from 2000ft, by Cecil Victor Shadbolt, 1882. Image courtesy Historic England Archive.

The British Library holds another of Shadbolt’s aerial photographs, made in 1884 over Blackheath (BL Maps C.44.d.49.).

By the turn of the twentieth century, rockets were also employed to carry cameras into the air. Even pigeons were fitted with miniature cameras, a technique first demonstrated in 1907. Soon after, aeroplanes joined this list, offering a more stable and controlled platform for airborne cameras.

Photograph of a pigeon with German miniature camera

Pigeon with German miniature camera, during the First World War. Wikipedia.

After the outbreak of the First World War, these methods were used for reconnaissance purposes, gathering intelligence about enemy trenches or build-ups of troops and artillery, and became of major importance in the planning of engagements. Mosaics of overlapping images were put together to cover entire trench systems.

WW1 air photo mosaic

Map. No. 5522. Air photo mosaic sheet 36 I 26. Image courtesy Imperial War Museum. © IWM Q 47658.

The need to revise and re-draw maps led to the development of systematic aerial survey techniques. During the course of the war, the major combatant nations employed a variety of methods - optical techniques involved projecting aerial photographs onto existing maps and tracing points from one to the other, while graphical methods allowed points to be plotted from perspective grids that were drawn onto and correlated between the images and the existing maps.

The high value placed on the contribution of aerial survey to the war effort is indicated by the sheer volume of images made - in the first nine months of 1918, British forces alone took over five million aerial photographs. They could be processed and delivered in under one hour from the time the pictures were taken.

WW1 aerial photograph

Reserve Army Front: vertical of Thiepval village, and German front-line and support trenches, while undergoing bombardment by British artillery. Image courtesy Imperial War Museum. © IWM Q 63740.

Attempts were also made to transfer to vertical imagery a set of techniques previously developed for horizontal imagery – terrestrial photogrammetry, as it was known, utilised overlapping pairs of horizontal views taken from the ground in combination with stereoplotting devices to recreate and plot the landscape. However, the trials met with little success, as inconsistencies in the angles of the vertical images could not be eliminated.

Terrestrial photogrammetry continued to be used and developed after the war. The glass plates shown below carry overlapping negative images taken by British surveyors during the Iraq-Turkish Boundary Survey of 1927, and were made with a photo-theodolite, in which a camera was inserted into the surveying instrument.

Glass plates used in terrestrial photogrammetry

Glass plates made by the Iraq-Turkish Boundary Commission using the Wild photo-theodolite, 1927. BL shelfmark not yet allocated.

Despite the high costs associated with aerial survey, the technique brought with it significant advantages over traditional land-based methods. The images below, made by the Anglo-Italian Somaliland Boundary Commission in 1929, demonstrate its use in mapping large areas of inaccessible terrain. However, aerial surveys supplemented, rather than replaced land parties, who still surveyed control points onto which the imagery was to be fixed. In this early example they even constructed marks on the ground to guide the flights taking photographs above.

Aerial photographs of Somalia boundary

Vertical aerial photographs made by the Anglo-Italian Boundary Commission, 1929. BL WOMAT/ADD/87/1/7.

The image above demonstrates the complexities involved in identifying and interpreting features from the air. The following British War Office lecture slide from around the same era provides guidance in the art of black and white aerial photo interpretation.

Glass slide with photo interpretation guidance

Detail of Air Photographs, General Idea of Relative Depth of Tone, glass lantern lecture slide from the British War Office, c.1930. BL shelfmark not yet allocated.

The aesthetic of aerial photography soon spread into wider culture, and was taken up by European artists such as Robert Petschow and Laszlo Moholy-Nagy with an art movement called New Photography. The patterned and grid-like images represented their ideas around the influence of mechanisation on society at the time, and held out the hope of finding a new, ‘objective’ way of viewing the world.

Parking Lot in Chicago, by Laszlo Moholy-Nagy

Parking Lot in Chicago, by Laszlo Moholy-Nagy, 1938. Image courtesy National Gallery of Victoria, Melbourne.

The next article will continue this story through the Second World War...

Nick Dykes

04 June 2020

The history of cartography: shining a light

The University of Chicago Press’s History of Cartography project reached another milestone in its 40-year history a few weeks ago, with the publication of volume four: cartography in the European Enlightenment. Congratulations to its editors and contributors.

Images
Cover image of the History of Cartography volume four (University of Chicago Press), published in 2020

Devised in the late 1970s by the historians JB Harley (1932-1991) and David Woodward (1942-2004), the project envisaged a six-volume history of maps and mapping. Volume one (European prehistory, Classical and medieval mapping) came in 1987, followed by Volume two, the cartography of non-European societies (1992), volume three, the European Renaissance (2007), and volume six, the twentieth century (2015). The final volume, covering the nineteenth century, is in production.

What was so ground-breaking about the project was its aim to understand maps in their contexts, treating them as social objects created by, and in turn influencing, the people and societies who made and used them. This was a ‘between the lines,’ critical history of maps. Shining a light on them. Calling them to account.

With the exception of volume four, the History of Cartography is available as free online PDFs. So if you have the time and space to educate yourself, particularly with reference to the current protests following the killing of George Floyd by Minneapolis police officers, it’s a good place to start.

For example, you might like to look in colonial maps of the 17th centuries and beyond at the issue of what Harley termed ‘silences’ in maps. Often what is absent from a map can be as insightful as what is actually shown. This is nowhere clearer than in maps of British India and North America, the latter including little or no indication of the slavery upon which colonial institutions were built (I recently referenced this in a discussion of Farrer's map of Virginia, below).

278.a.3
Virginia Farrer, A mapp of Virginia discovered to ye hills.... 1651. British Library 278.a.3.

You might also wish to look at the Cartography in the Twentieth Century to see how the use of maps by the powerful and privileged often led to greater levels of injustice and inequality.

For example, Jeremy Crampton’s essay on maps and the social construction of race (pages 1232-1237), and particularly Amy Hillier’s summary of the insidious 20th century practice of redlining (pages 1254-1260). Redlining was US location-based housing discrimination which figuratively and literally drew red lines around urban districts that were deemed undesirable to provide housing insurance or mortgages to due to the racial composition of their borrowers and owners. The effect was to drive these areas and the people living in them into the ground.

Home_Owners'_Loan_Corporation_Philadelphia_redlining_map
Home Owners' Loan Corporation map of Philadelphia, 1936 (Penn University)

Redlining map of Philadelphia, 1936

The practice was outlawed in 1977. But the impact of it, and the racist attitudes at the heart of it, remain prevalent in 2020.

Tom Harper

02 June 2020

Survey of the River Euphrates

Growing interest in natural sciences in the 19th century resulted in the establishment of many scholarly societies devoted to the study and promotion of the advancement of specific disciplines, particularly geography. At this time military surveys were recognised as an instrumental administrative tool in generating data in order to produce accurate maps and charts describing physical features to aid communication, administration and commerce. The scholarly societies were often closely allied with colonial exploration which led to ambitious expeditions and scientific inquiries.

IORX3205

Arabia. By William Henry F. Plate … Drawn for Colonel Chesney's work on his Euphrates expedition. 1847. IOR/X/3205

One such example was the Euphrates expedition of 1836 lead by a British army officer Colonel Francis Rawson Chesney. The main objective was to establish a route “between the Mediterranean Sea and His Majesty’s possessions in the East Indies by means of a steam communication of the river Euphrates”. Finding a shorter route to India was the hot topic of the time. The East India Company sought a suitable solution to cut down the travel time between England and India. Chesney was involved in initial surveys in Egypt and the Middle East in the late 1820s where he investigated the possibility of passage to India via the Red Sea. In 1829 he submitted a report advocating the construction of the Suez Canal. He also brought to attention the feasibility of steam communication with India through the Euphrates. The king William IV himself expressed a desire that the route by the Euphrates to India should be put to a practical test. 

IORX3140
Map of the countries between the Mediterranean Sea and the Gulf of Persia on the line of the Euphrates, Tigris, Kuran ... from the original Surveys made by the late expedition under Commander H. Blosse Lynch. 1847. IOR/X/3140

In late 1834 when Chesney received funds for the expedition he assembled a capable group of naval and military officers including the explorer Henry Blosse Lynch of the Indian Navy and a geologist William Francis Ainsworth, president of the Royal Physical Society of Edinburgh. He also selected workmen from the Royal Artillery, Royal Sappers and Miners qualified in steam machinery, surveying and drawing. 

Two prefabricated iron-steam riverboats constructed in Liverpool by John Laird and Company were ingeniously designed to allow for the components to be shipped from England to the Eastern Mediterranean and transported overland nearly 140 miles to Bir (Birecik in modern Turkey). There the ships were assembled on the banks of the Euphrates in a makeshift shipyard.

X570 i

Map showing the expedition’s overland route from Aleppo to Bir River Euphrates with the Cilician Taurus and Northern Syria. Published by Col. Chesney, 1849. X.570.

Before the expedition departed, the president of the Board of Control for India, Lord Ellenbourgh, issued a clear instructions reminding Chesney that he should “always bear in mind that [the practicability of navigating the Euphrates] is the one object of your expedition, and that scientific inquiries, however interesting, are no to be allowed to detain you”. But the survey was so much more than just a geographical inquiry. It was an unusual mix of military, commerce, scientific, even Biblical historical study. Yes, as strange as it sounds along with other observations the officers investigated the probability that “the country about the sources of the Euphrates and Tigris was the seat of Paradise”! (as described in Chapter XII of Chesney’s The Expedition for the survey of the rivers Euphrates and Tigris… published in 1850). 

X 570  map v

Detail showing cross section of the river as recorded in May 1836, from map V. The River Euphrates from Werdi to Hit... Published by Col. Chesney, 1849. X.570.

The main task of determining the depth, current and state of the river Euphrates was carried out carefully. The officers made magnetic observations, recorded information on phenomena of geography, physics, meteorology, gathered geologic specimens and recorded archaeological sites.  This wealth of data was included in Chesney’s publication and the gathered data was used in the compilation of detailed charts of the region’s waterways from the Mediterranean to the Persian Gulf. 

X 570  map viii

Detail showing ruins of Babylon from map VIII. The River Euphrates from the Kuthah River to El Wuja Island and Village also the River Tigris from the Abu Hitti Canal to Judifah Island … Published by Col. Chesney, 1849. X.570.

X570 xii (2)

The Shatt el ‘Arab from Basrah to the bar of the River Euphrates and the River Karun from Salmanah Isle to Mohommerah with the Bah-a-Mishir surveyed by Colonel Chesney and the officers of the expedition. Published by Col. Chesney, 1849. X.570.

The Euphrates project was shelved and the shorter route to India was eventually established in late 1869 via the Suez Canal. Nevertheless, the Chesney’s survey is an invaluable source of information which provides in depth insights into the region’s hydrography which changed significantly in the 20th century due to major irrigation, drainage, and desalinization projects.

 

28 May 2020

Automated text extraction from colonial-era maps of eastern Africa

After recently completing a pilot course in Computing for Information Professionals at Birkbeck University, I have just released a new dataset containing the text extracted from almost 2,000 colonial-era maps and documents covering eastern Africa. The resource is available now from the Shared Research Repository, and provides access to thousands of names of historical settlements and regions, descriptions of historical land use, topography and vegetation, and notes of ethnographic, military or administrative context.

Detail of a manuscript map of Umkamba Province in Kenya held at the British Library in the War Office Archive

Detail of a manuscript map entitled Masailand held at the British Library in the War Office Archive

Details of 'Umkamba Prov. part of (Central)', 1901 - BL Maps WOMAT/AFR/BEA/54 (above), and 'Masailand', 1901 - BL Maps WOMAT/AFR/BEA/41 (below). Transcribed words have been highlighted.

The resource consists of a downloadable spreadsheet, which lets users browse or search the extracted text. I hope it will be of particular use in identifying and locating place names in eastern Africa during the colonial period, for which there is a gap in current research resources. I’m also hopeful it will facilitate the contribution of these maps to studies of the history of the environment.

The text was harvested from maps and documents that are held at the British Library in the War Office Archive, a collection of over 14,000 mostly unique, hand-drawn items originally kept by the British War Office between c.1880 and 1940 and used to compile printed maps over large parts of the world. They came from a variety of sources, including military surveyors, explorers, missionaries and spies. Generous funding from Indigo Trust recently allowed us to digitise those items relating to eastern Africa.

Automated extraction of the text was carried out using the Google Vision API, which found a total of 633,451 pieces of ‘text’ on the maps. However, after the majority of erroneous results or results that were not useful had been cleaned out, the final dataset was reduced to 317,133 transcriptions. These are sorted alphabetically and displayed in an Excel spreadsheet, shown in the following screenshot:

Detail of resource providing text extracted from maps held at the British Library in the War Office Archive

The order in which the pieces of text were transcribed from the maps was retained in the second column of the spreadsheet so that, if the spreadsheet is re-ordered by that column, each word can also be seen in its original context – for example, the text in the screenshot below can be read from top to bottom (‘The topography has been supplied...’):

Detail of resource providing text extracted from maps held at the British Library in the War Office Archive

The spreadsheet enables a user to identify the image in which any piece of text appears, and links to a geographical search interface for the archive, shown below, which in turn provides links to high-res versions of the images and their catalogue records on the BL website. The combination of these resources lets users identify each piece of text and see it in context on the face of the map.

Geographical search interface for maps held at the British Library in the War Office Archive

The maps are drawn in a wide variety of different hands, and the text often overlaps or is written over background features, making automated transcription tricky. Some errors do remain - for example, where individual characters have been incorrectly transcribed within words, though the words themselves should still be identifiable. In addition, not all words appearing on the maps were captured.

The resource came about after I was fortunate enough to join a cohort of colleagues from the British Library and the National Archives attending the pilot postgraduate course at Birkbeck. After speed-learning Python and SQL coding languages in the first term, I then focussed on the development of a software tool that enlists the Google Vision API to auto-transcribe text found on maps. Once made, I set it to work harvesting words found on the eastern Africa maps.

I am very grateful to BL Digital Curator Nora McGregor, who set up and coordinated the initial pilot (now launching this autumn as an Applied Data Science Postgraduate Certificate), to the Institute of Coding, who funded it, and to BL managers for allocating study time during work. This project would also not have been possible without Indigo Trust, whose generous funding to conserve, catalogue and digitise War Office maps over the last five years has made them accessible to the world online, and enabled further initiatives such as this.

Nick Dykes