Monthly Archives: January 2018

A silk escape map

The story of silk escape maps in the second World War is now deservedly well known. The maps, printed on silk as a resilient alternative to paper, were carried by Allied air crews to help them find their way home if they came down in enemy territory. Similar maps continued to be produced after the war, and the Bodleian has a small collection of maps produced in the 1940s and ‘50s. However, the recent arrival of a silk map in the Bodleian Map Room caused a certain amount of interest.  

For one thing, this map appears actually to be on silk. So called ‘silk maps’ were initially printed on silk that had been judged to be below the standard required for parachutes in the early 1940s. But once silk supplies ran out they were made of acrylic material that just isn’t as nice. This one is soft and silky and would make a lovely scarf.

The style of the map is reminiscent of the British silk escape maps of WWII. It has a utilitarian look – it was designed to be functional rather than marketable – with different islands on insets identified by letter codes. The lettering style, layout, and presence of print codes but absence of standard publication information are all typical of WWII era silk maps. It is however in only 2 colours (brown for the hill-shading, black for everything else) –  British silk maps from the same period were more often printed in 3 or more colours.

The map shows ‘Celebes’ – part of Indonesia and known as Sulawesi officially since 1945 – and surrounding islands. The map was made by the RAAF (the Royal Australian Air Force); copies are held in map libraries in Australia and the US, tentatively dated to 1943 (SP 3) . It is the first Australian silk map to be acquired by the Bodleian. Its condition shows the resilience of this apparently fragile material – apart from a few loose threads at the edges, it looks as good as new.

Want to know more about the story of silk map production?

This website http://www.silkmaps.com/ gives general background on silk military maps
This article (beginning p.30) explains the role played by MI9 http://www.defencesurveyors.org.uk/Images/Ranger/Ranger%20Volumes/Ranger%20Summer%202009.pdf
The article ‘Wall tiles and Free Parking’ http://www.mapforum.com/04/april.htm tells some of the story behind the silk maps’ production in Britain and their use in a POW camp.

For a more detailed account, the book ‘Great escapes’ by Barbara Bond (Glasgow: Times Books, 2015; ISBN 9780008141301) is a fascinating read.

The National Encyclopædia Atlas

The National Encyclopædia Atlas is a beautiful example of a mid-Victorian atlas. Published in 1868 and intended for both home and school the book features maps of the major countries of the World as well as a short introduction with a number of World maps. Using the double hemisphere method the atlas has two different World views, both thematic. The first has a physical map showing mountain chains, river systems, trade winds and ocean basins, with views of the  Northern and Southern Hemispheres and Land and Water Hemispheres. Double Hemisphere representation is a long-established way of portraying World maps, though the changing of the positioning of the poles to highlight a side of the Earth more land or water based is an unusual feature.

 

Physical Map of the World, from The National Encyclopædia Atlas 

 

Directly underneath the two hemispheres is a strip showing mountain profiles, describing itself as a ‘Imaginary section showing comparatively the greatest elevations of the land & the greatest ascertained depression of the sea’. Mountains feature on the next page, with the highest in the Western and Eastern Hemispheres at left and right and river systems going from top to bottom.

 

 

The highest mountain in the Eastern Hemisphere, on the right, is of course Mount Everest, which at the time of the atlas was measured at 29,002 feet (it is now measured at 29,029). Just above is a balloon labelled Green. Charles Green was a celebrated balloonist who in 1838 rose to 27,146 feet in an ascent which saw temperatures drop to as low as -27°.

The second World Hemisphere map in the atlas shows ocean currents and isothermal lines (now called isotherms), as well as a small inset showing the comparative distribution of rain. Isothermals are lines showing areas where the temperature of air or sea are the same and is a term first used by the naturalist Alexander von Humboldt during his study of plant distribution throughout the World. Ocean currents are beautifully depicted in graceful pink curves and the map graphically shows the Gulf Stream and the Arctic Currents which have such an effect on the weather patterns and temperatures of Great Britain and the East Coast of the United States.

The National Encylopædia Atlas, 1868, published by William Mackenzie. 3.Δ 1326

Clay on the Western front, a German viewpoint

Geological maps are an important part of cartography. Showing underlying soils and rock formations they have been used to illustrate papers in geology, in helping the planning and construction of canals, railways and other structures and in the extraction of minerals from the earth. Their use in times of war is less obvious, though no less important, as the following map shows.

Kriegsgeologische karte von Nord-Frankreich, 1918. C1:3 (295)

The map is one of a series produced by the German 4th Army in July of 1918, a crucial time in the latter stages of the war. Peace negotiations with the new Soviet Government in Russia released a large number of German forces to the Western Front, strengthening plans to launch a series of attacks before the arrival of American forces. Initially successful – at one point German forces were within 40 miles of Paris – counter-attacks by Allied troops soon stopped and then re-captured German gains.

In this map from Harmsworth’s Atlas of the World (c1922, 2027 c.225) the German advances made in March 1918 can be seen. The thick blue line is the front-line before March, the  green lines show the advances made by the German army from March 1918 and finally the thick red line is the front-line at the Armistice in November.

The front page of the evening edition of the Pall Mall Gazette on the day the German attack was launched. 21st March, 1918. N 2288 b.4.

This geological map shows a cause for one of the  defining features of the War, mud. The areas of grey that start to appear in the bottom right of the map are the beginnings of the clay beds (ton in German) that would lie a metre or so under the surface throughout the Flanders battle grounds. These clay beds stopped any water seeping into the ground and the intricate system of dykes and drainage channels that controlled the flow of water in peace time had long-since been destroyed by the millions of shells fired over the area. The map states in the bottom left ‘Soil easy to handle; stable only in dry weather. After precipitation the water is kept close to the surface. Funnels fill up quickly with water (Boden leicht bearbeitbar…).

Kriegsgeologische karte von Nord=Frankreich, Blatt Dünkirchen, 1918. C1:3 (295)