MapCarte 364/365: Detail of area around the Broad Street pump, by John Snow, 1854

MapCarte365_snowNo-one learns about cartography without studying the map of cholera around the Broad Street pump in Soho, London in the mid 1800s by John Snow. By any measure of importance, Snow’s map has become perhaps the standard-bearer for showing us how a map can say so much more than words alone.

Snow wasn’t a cartographer. In fact many of the maps showcased in MapCarte are by non-cartographers. He was an epidemiologist, a physician and the father of anaesthesia. He was also the personal physician to Queen Victoria. Snow also gave us a classic piece of cartography which resulted in his work in tackling the cholera epidemic of 1854. Knowledge of the disease transmission process was poorly understood. Snow set about trying to make sense of the disease and its spread by plotting all known deaths on a map. It was this instrument that led to his postulating that since most deaths seemed to occur in the vicinity of a water pump on Broad Street then cholera was likely a water borne disease.

“On proceeding to the spot, I found that nearly all the deaths had taken place within a short distance of the [Broad Street] pump. There were only ten deaths in houses situated decidedly nearer to another street-pump. In five of these cases the families of the deceased persons informed me that they always sent to the pump in Broad Street, as they preferred the water to that of the pumps which were nearer. In three other cases, the deceased were children who went to school near the pump in Broad Street…

With regard to the deaths occurring in the locality belonging to the pump, there were 61 instances in which I was informed that the deceased persons used to drink the pump water from Broad Street, either constantly or occasionally…

The result of the inquiry, then, is, that there has been no particular outbreak or prevalence of cholera in this part of London except among the persons who were in the habit of drinking the water of the above-mentioned pump well.

I had an interview with the Board of Guardians of St James’s parish, on the evening of the 7th inst [7 September], and represented the above circumstances to them. In consequence of what I said, the handle of the pump was removed on the following day.
—John Snow, letter to the editor of the Medical Times and Gazette

And so spatial epidemiology was born. Thematic cartography was also brought to the fore as Snow’s overplotting of a phenomena on a street map brought to light new information from the spatial pattern of data.

MapCarte365_snow_detailSnow’s map was ingenious and it’s remarkable that such a simple technique had not become more widely used prior to his efforts. It’s design is so utterly simple that we perhaps ignore its beauty. The simple black and white street network with road labels and the stacked approach to plotting deaths along the roads couldn’t be simpler if we tried to recreate it. The complexity of the study is brought to life through the simple graphical interface of the map. Snow didn’t need any more complex map to interpret his thesis and in so doing, he shows how maps can say so much with so little.

Of course, history tells us that by the time Snow had realized the mode of transmission, and action was taken to remove the handle from the pump, the disease was already abating. That shouldn’t reduce the importance of his work to epidemiology and public health or to his map in relation to cartography. It is rightly one of the most important maps ever made.

You can learn more of Snow’s map through the John Snow Society here or view a digital copy of the book he wrote (which contained the map) here.

MapCarte 358/365: Cairo to Khartoum by The Graphic, 1884

MapCarte358_cairokhartoum1MapCarte358_cairokhartoum2Selection and omission is a key cartographic requirement. We make many decisions about the content of the map. One of the more dramatic consequences of this process is omission of all but a single geographic feature and this map of the River Nile from the late 1800s illustrates the principle perfectly. The whole river itself is over 4,000 miles in length and 2 miles in width at it’s widest. It passes through 11 different countries, though this map only illustrates the portion from Khartoum (where the Blue and White Nile meet) to the coast at Cairo.

General reference maps simply wouldn’t suit the purpose of highlighting the settlements and places along a river. The scale wouldn’t allow it and the amount of white space would make the balance of the map inappropriate. You’d be forced into adding all sorts of other topographic detail simply to fill space.

Instead, as a supplement to The Graphic, this map focuses on just the river. It becomes a linear cartogram with some segments straightened and a lack of almost all other topographic detail except for places that directly border the river itself. It’s akin to some of the classic early strip maps used to map roads and it translates well to a river. The river becomes the central anchor to the two page spread and around it are beautifully illustrated vignettes – panoramic scenes of the towns, villages and natural scenery along the river.

Maps can omit so much and still be perfectly suited to telling the story of the form itself. Here, the river and only the river. It makes perfect sense to omit all else.

MapCarte 356/365: The Nolli Map by Giambattista Nolli, 1748

MapCarte356_nolliThe Italian architect and surveyor Giambattista Nolli is perhaps best known for his epic ichnographic plan of Rome, known as the Nolli map. He began his exhaustive survey in 1736 and eventually engraved and published the map in 1748 across twelve sheets measuring 176cm by 208cm when pieced together. The map was effectively commissioned by Pope Benedict XIV as a way to map and subsequently demarcate Rome into 14 districts. The detail of the map reflected the architectural achievements of Rome and of the Papacy itself of the time.

MapCarte356_nolli_detailThe map is a phenomenal achievement of technical work and of detail and precision. It also incorporates some interesting design choices, not least the orientation of east to magnetic north to reflect the use of the compass to determine bearings in relation to the city’s layout. In terms of depiction, the map illustrates the importance of figure-ground in cartographic design. Nolli followed a previous work, the Bufalini map of 1551, which shaded buildings and other features in dark while ensuring open spaces were white. Additionally, he maps the various colonnades of important public spaces such as St. Peter’s Square in black, almost in the style of an architectural blueprint.

MapCarte356_nolli_detail2While the map undoubtedly has historical significance both in the mapping of Rome and also as a scientific and technical achievement, the contribution to cartography is also hugely important. The dark grey hachuring for the buildings highlighted the importance of colour, depth, contrast and texture in defining visual contrast. Nolli used black to indicate monuments and white outlines to show the locations of ancient monuments that no longer exist. S-shaped curves were used to denote contours and slopes which was before contours were used more commonly to illustrate elevation. A waterlining effect was used as a vignette for the river and various symbols used to show locations of other features with qualitative differences indicated through design (e.g. open and closed drains). The use of precise illustrative symbols was rare in maps of the time.

You can read more about the Nolli map, and view an online archived version, at the Interactive Nolli Map website here.

MapCarte 348/365: Abekawa-dōri sanchū ichien ezu by Ichiryūtei Shoraku Dōjin, 1862

MapCarte348_aberiverInstead of creating general purpose reference maps that depict the topographic detail of a specified area, an alternative approach is to let a specific feature define the area itself. In this sense, the feature becomes the central player in the map and all other content becomes its supporting cast. It also determines the shape, format and, possibly, the size of the finished product. This superb example shows the Abe River region in Japan from the mid 19th century. The river itself defines the shape and scope of the map with the flow from north-west to south-east being depicted from left to right across the map, with straightening being used in places. In this case, north is towards the upper left rather than directly upwards.

The map is predominantly pictorial with relief in particular shown pictorially. Relief is drawn in aspect while the map in general is planimetric; a fairly typical approach of the time in Japanese cartography. It’s also worth noting that the mountains are not uniformly drawn with their base at the bottom and peak at the top across the map – they change orientation so, for instance, toward the left of the map it’s noticeable that the mountains are rotated left by 90 degrees to show them as the origin of the river and make the flow of the river make more sense visually.

MapCarte348_aberiver_detailThere is very little text on the map itself, the reverse side being used for notes on the geography of the region. This allows the map to remain clutter free and for the topography to be drawn in detail. The finish is in watercolour and ink with major land uses benefiting from different hues to demarcate the landscape.

The braided river flowing through alluvial deposits and floodplains is particularly well represented and stands out amongst other rich colours of the surrounding mountains. The stippled pattern for the plains adds to the texture of the map and creates a sense of realism that a relatively solid fill doesn’t. There’s no frame as such and the river washes out into the sea to the right.

A beautiful map and an example of allowing your subject or theme dictate many of the other cartographic choices to be made.

MapCarte 346/365: Bird’s eye view of South Africa by G. W. Bacon, ca 1890

MapCarte346_southafricaBird’s eye views fascinate us because they give us a panoramic, perspective view of a landscape as if we were seeing it with our own eyes. Typically, such views are of cityscapes or relatively small areas but with some cartographic license we can turn our skills to the depiction of much larger areas. This chromolithographic print, published by G. W. Bacon captures an entire country using the technique. It’s neither perfectly planimetric nor uses a progressive projection but there are subtle changes in the perspective from south to north, accentuated by the depiction of landforms throughout.

The content is fairly routine in terms of topography with roads, rivers, towns and cities as well as major mountains, rivers and some political and administrative features. Insets are used to show the Transvaal in the upper left and northern Natal in the lower right giving the layout balance as well as space for more detail in these areas.

MapCarte346_southafrica_detailOf course, timing is everything in cartography and the map was was published just after the First Boer War (1880-1) and in the period leading to the Second Boer War (1899-1902). The British were particularly keen to understand the landscape and names which were becoming part of daily life in newspapers. Maps such as this helped contextualize the far off land and better appreciate the places which had, by now, been discovered to hold large gold and diamond reserves.

More than all of this, the map is well coloured and pleasing as a form of cartographic art. The mountains, in particular, are depicted using a plan oblique technique and sit well amongst the otherwise flat plains. The use of light across the image hints at the way sunlight might hit a picture with the south being slightly darker than the north, particularly around the inset. The same is true for the rendering of the water and around the lower right inset. This gives the work added depth.

MapCarte 344/365: Geographical Cards by Charles Hodges, 1827

MapCarte344_hodges5English bookseller and stationer Charles Hodges original Geographical Cards were published in 1827 and subsequently in 6 different versions until c.1830 when he ceased trading. They have become highly collectible and prove the versatility of maps in their ability to suit a wide variety of purposes. Here, as a backdrop to the most simple of games – the humble pack of playing cards. To this point, there had been a tradition of creating playing cards with engraved representations of educational and scientific subjects. Hodges carried on this tradition by using maps as the focus of his own cards. The cards were made and manufactured by Stopworth & Son in London.

The Aces show maps of the four main continents of Europe, Asia, Africa and America. The court cards depict historical persons representing the continent and the other numerical cards show maps of the respective countries. George Washington is the King of Spades and King George IV is the King of Hearts.

MapCarte344_hodges4 MapCarte344_hodges3 MapCarte344_hodges2 MapCarte344_hodges1The maps themselves are small format (obviously) but in this case small is beautiful and each map is exquisitely engraved and coloured. Coastlines benefit from a waterlining vignette and for such small maps, the typography is of a suitable level of detail and shows excellent positioning. In every sense, these are excellent maps albeit their primary purpose is illustrative in support of the deck of cards.

Hodges later made use of the same printing plates and produced a game using cards that had no suit information but, instead, had the longitude and latitude of capital cities printed as well as more elaborate colouring, particularly in the colour applied to the seas and oceans.

MapCarte344_hodges6He also produced a set of forty cards without suit marks or the court cards simply as a miniature atlas. These appeared in a small slip-case and had gilt-edges.

MapCarte344_hodges7Maps can be used in myriad ways and as a mechanism to provide not only an attractive illustration but also additional interest. A beautiful way of using cartography.

MapCarte 337/365: A New and Enlarged Description of the Earth by Gerardus Mercator, 1569

MapCarte337_mercatorThere’s arguably no more widely known figure in historical cartography than Mercator. His legacy has been the mathematical basis and projection developed and first used in his map of 1569. The map’s content at the time was rich and presented as complete a knowledge of the Earth as had been seen before. The projection, though, surpasses the content and is still the basis of many maps and, in particular, navigational charts to this day. The reason is simple – the Mercator projection allows one to plot straight lines of constant bearing (rhumb lines) which makes it a perfect map to support navigation.

MapCarte337_mercator_detail

The map was produced across 18 separate sheets measuring a total of 202cm wide by 124cm tall. It was compiled from a range of sources including previous maps made by other cartographers, Mercator himself and portolan charts by Portuguese and Spanish sailors. These charts provided Mercator with the detail of coastlines that made this new projection so useful for supporting navigation. It was the first time the detail and projection had been used combined. The map is littered with cartouches and other marginalia including descriptions of the science of measurement that forms the basis of the map. In one such legend Mercator states that his first priority is “to spread on a plane the surface of the sphere in such a way that the positions of places shall correspond on all sides with each other, both in so far as true direction and distance are concerned and as correct longitudes and latitudes.”

A remarkable map of the time and one that continues to be used, and it has to be said mis-used, to the present.

MapCarte 325/365: Mount Everest Expedition by Major Henry Morsehead, 1921

MapCarte325_morseheadThe Great Trigonometrical Survey of India in 1856 established Mount Everest (known as Peak XV) as 29,002 ft (8,840m). The survey itself was incredibly accurate compared to the modern height of 29,029ft (8,848m). It was named Mount Everest by the Royal Geographical Society upon recommendation by the British Surveyor General of India, Andrew Waugh, who named it after the man he succeeded, Sir George Everest. It was nearly 100 years later, in 1953, when Tenzing Norgay and Edmund Hillary made the first official ascent though debate continues to surround the possibility that George Mallory and Andrew Irvine may have reached the summit as part of the 1924 expedition. They made a final attempt on the summit on June 8th but disappeared in the clouds after being spotted high on the mountain. Mallory’s body was recovered in 1999 at a height of 26,755ft (8,155m). Surveys and maps of Everest were critical in the understanding of the mountainscape, the plotting of the various potential routes to the summit and the eventual success. The map made by Major Henry Morsehead as part of the 1921 expedition is arguably the finest early, detailed and complete map of the region.

MapCarte325_morsehead_detailThe 1921 expedition was in effect a reconnaissance by the British who reached an elevation of 22,970ft (7,000m) on the North Col after a 300 mile march. Nepal didn’t allow foreigners into the country so the British expeditions had to approach the region from the Tibetan side. The map clearly illustrates the divide between nations in the limit of the detail, with Everest being shown on the south edge of the detailed map. The impressive detail is wonderfully rendered with hand drawn hillshading in grey to identify slope and aspect. Darker shading shows higher areas and ridges are shown as if illuminated vertically. Water and glacial features are shown in a light alpine blue hue with only one further colour, red, used to show the different routes through the region. The map is a work of art in relief portrayal and clarity and a result of more than simply marching to Everest itself. This map required Morsehead and his team to explore the entire region in harsh conditions. They weren’t alone in their map-making endeavours with others in the team also undertaking photographic surveys, collecting specimens of flora and assessing the geological structure. Indeed, Alexander Heron’s Geological map is also impressive in its own right.

MapCarte325_heronDespite initial thoughts of using the 1921 expedition for a full assault on the summit, the trip was eventually led as reconnaissance. Before they had left the region, the Royal Geographic Society’s Mount Everest Committee had already established a subsequent expedition for the following year to go for the summit. The 1922 expedition used Morsehead’s map to push on via the North Ridge route to an elevation of 27,300ft (8,320m) which was the first time a human had climbed above 8,000m. It was also the first attempt on Everest that used bottled oxygen to counter the effects of elevation. George Mallory, who had taken part in the 1921 expedition, had discovered a potential route to the summit though on the third attempt seven porters died in an avalanche and the expedition abandoned. They had established a new record climbing height but the lure of the summit would have to wait.

To date over 4,000 different climbers have made nearly 7,000 summits. Some 250 people have died trying to climb Everest. Today’s climbers take modern equipment and digital maps yet for its time and, still, Morsehead’s map retains its status as a cartographic gem that supported early attempts on the summit.

 

 

MapCarte 323/365: Bathymetrical chart of the Oceans by John Murray, 1899

MapCarte323_murrayOcean exploration was a key scientific objective in the late 1800s. Any numbe rof oceanographic, biological, chemical, geological and physical discoveries had been made and one of the preeminent scientists was John Murray. The results of his voyages on H.M.S. Challenger led to this map, the first to make its focus the deeps, what occurs underneath the surface rather than previous voyages and explorations that were concerned with coastal and shallow waters. Murray recognised that measurement at depth required correct and operational instrumentation because it was indirect measurement that was required. Why was this necessary? Accurate survey of the ocean floor was paramount to the correct siting of telecommunications cables across the ocean basins. For that you needed an accurate map.

This map for the first time showed ‘the deeps’ according to Murray. The mid-atlantic ridge is clearly shown as are areas of the Atlantic Ocean that are greater than 3,000 fathoms deep. In many ways, Murray, the Challenger expeditions and this map were critical in the establishment of oceanography as a distinct branch of science.

MapCarte323_murray_detailMurray went beyond calculating bathymetry though, he estimated temperature of the ocean floor as distinct to the surface as well as the amount of light penetrating the darkness and the impact on flora and fauna and marine deposits. The map uses subtle bathymetric tinting and is the first to officially name many of the deep ocean floor troughs. It’s not a complex map but it’s apparent simplicity belies the efforts and science that went into making it.

Maps do not need to appear complex. They can be used effectively to communicate scientific discovery, accuracy and new knowledge. This map, for its time, was revolutionary and was the first to give us a sense of what lies beneath the surface of the vast expanse of seas and oceans.

Murray’s ground-breaking essay on The State of Ocean Science can be read here.

MapCarte 322/365: A new map of England and France by James Gillray, 1793

MapCarte322_gillrayMore satirical cartography in this MapCarte entry because maps are extremely powerful objects with which to convey a message designed to be politically charged or even propagandist. Here, James Gillray creates a caricature of England and its relationship with the rest of Europe, in particular showing disgust at nearest neighbours, France.

The map was created in 1793 amidst murmurings of impending French invasion as part of their wider revolutionary tendencies. How best to create a fervently patriotic show of distaste for invasion that is sure to increase sympathies to the ruling King and anti-French sentiment? Use a map! Gillray fits the shape of John Bull into the England and Wales. Bull, of course, is the stereotypical personification of England: a witty, jovial, stout matter-of-fact man. The French invasion of bum-boats is repelled by the defecating Bull from the ports of his ‘south coast’.

Even the French coastline is configured to look like a face with the stream of muck being thrown unceremoniously straight into the face itself. Gillray was a master of satirical caricatures and a commentator on political and social issues. This work captures the strength of feeling declared by King George III against the potential of a French invasion. Cartography as a vehicle for satire and commentary is indeed a powerful mechanism in the hands of a skilled craftsmen and although the sketch is merely that – a sketch rather than an accurate portrayal of topography – it needs no more than a general shape on which to hang the message.