A brief history of silk maps|
The concept of silk maps is far from new. Archaeological evidence from ancient Chinese tombs indicates that maps showing trade routes were being drawn on pieces of silk as long ago as the second century AD.
In Europe, novelty silk scarves decorated with maps of spa towns were popular during the 18th and 19th centuries, and this tradition continues with US States, tropical islands and even whole countries occasionally being printed on commemorative and souvenir scarves.
It was with the outbreak of World War II, however, that the idea of printing maps on fabric really came into its own. From early in the war, British aircrews were issued with 'survival kits' to help them evade capture or escape imprisonment should they be shot down over hostile territory. These kits were packed into a small oilskin pouch and typically included a small saw blade, needle and thread, currency, phrase cards, a tiny compass the size of a thumb nail and, most crucially, a silk map.
It had been quickly realised that maps printed on silk, or its manmade equivalents (such as rayon-acetate or nylon), were far superior for escape and evasion purposes than conventional paper or linen-backed maps. Silk maps are extremely durable, do not disintegrate in water, are not damaged by repeated folding and unfolding or by being screwed up into a ball, and are silent to unfold and use. Most importantly they are easy to conceal. Sewn into the lining of a jacket or the hem of an undergarment, or hidden in the hollowed-out heel of a boot, a silk map was unlikely to be found, at least in an initial prisoner search.
Moreover, the silk maps provided welcome warmth to airmen shot down over Europe, while those in sub-tropical areas such as Burma found them invaluable as head and face-wraps to keep off the swarms of mosquitoes.
The silk maps were developed by MI9, the escape and evasion wing of British Military Intelligence. The cartography was supplied by the Bartholomew map company, with all copyrights waived in support of the war effort. Waddington plc, known for games such as Monopoly, employed its experience of detailed printing on fabric to print the maps with the required detail. The silk was specially treated for durability and the impressive printing clarity was achieved by adding pectin to the ink.
The maps were double sided, with 'RESTRICTED' printed along the border and a sealed selvage to prevent fraying. Enormously detailed, they showed cities, towns and villages, lakes and rivers, population densities, elevations, roads, railroads and mountain passes, military installations and sometimes even ocean currents, navigational star charts and, for northern regions, the seasonal limits of ice cover.
Inspired by the success of the British maps, American Intelligence adopted the idea. Escape maps were standard issue to all U. S. Air Force servicemen from 1942.
Several hundred thousand silk maps were produced during World War II, and it is estimated that of the 35,000 Allied troops who managed to escape from behind enemy lines, more than half used a silk map. A number of these maps have survived and are now highly collectable.
Silk maps continued to be produced throughout the Cold War era. More recently, they were issued to airmen during the Gulf War, indicating that despite advances in the technology of war, silk maps still have an important part to play.