Читать книгу Great Escapes: The story of MI9’s Second World War escape and evasion maps - Barbara Bond - Страница 14

Hutton was almost certainly unaware that the efficacy of silk as a suitable medium for military maps had long been recognized. Indeed, the oldest surviving silk map in the world is a military map, known more commonly as the Garrison Map, excavated in 1973 from the Han Dynasty Tomb No. 3 in Mawangdui, Changsha, in Hunan Province, China. It was one of three silk maps found on the site, the others being a topographical map of the region and a city map. The Garrison Map has been dated to the middle of the second century BC. It was unearthed in twenty-eight fragments, moisture and pressure having taken their toll during 2,000 years of burial in a small box. The fragments were restored and then a reconstruction of the map was undertaken by Chinese scholars.

The Garrison Map covers the region between Mount Jiuyi and the Southern Ridges in Ningyuan in southern Hunan province, China. The map shows mountains, rivers and residential settlements, and in particular it indicates the locations of the garrisons, defence regions, military facilities and routes of nine army units. It is the oldest known map on silk, dating from the second century BC

A reconstruction of the Garrison Map.

The map carries no indication of scale but, by comparing it with modern mapping, it is estimated to be in the range 1:80,000 to 1:100,000. It has been drawn on a rectangular piece of silk which measured 98 cm by 78 cm. The map was originally drawn in three colours, black, red and blue/green, using vegetable-based tints and is orientated and marked with south at the top and the left side marked east. Water features are shown in blue/green, with some background features and place names in black but the military content of the map is emphasized in red, showing the size and disposition of army units, command posts, city walls and watchtowers. Settlements are shown, together with the numbers of inhabitants. The boundary of the garrisoned area is marked and frontier beacons (observation outposts) are shown. Topographic detail is stylized, so that mountains are shown as wavy lines rather than by any attempt to represent their real form and shape. Roads are shown with distances between some settlements clearly marked, as are river crossing points: in modern military parlance, this is referred to as ‘goings’ or terrain analysis information and was a technique also utilized by MI9 in the production of some of their special area escape and evasion maps.

While the Chinese are understandably keen to stress the relevance of the three maps in terms of how they reflect their nation’s achievements in surveying and mapping techniques in the wider context of historical cartography during the period of the Han Dynasty, the relevance here is that the Garrison Map was undoubtedly produced for military purposes and was drawn on silk. There are later examples of military mapping produced on silk in China. Seventeen hundred years after the Garrison Map was produced, the Garrison Outline Map of Shanxi was produced during the Ming Dynasty, although the later map was regarded by Chinese scholars as greatly inferior to the Han Dynasty Garrison Map, not least because the earlier map was drawn in colour and showed far more military detail than the Shanxi map.

In the USA during the Civil War, General Sherman was known to have had monochrome maps printed on cloth during the Atlanta campaign. The Library of Congress map collection contains many examples of Civil War maps printed on cloth, including the map illustrated here, showing ‘Part of Northern Georgia’, produced by the Topographical Engineer Office in Washington DC in 1864.

The Intelligence Division of the US War Department in Washington DC produced a map of Cuba in 1898 and one of China in 1900, both printed on cloth. Details of these examples were contained in a letter dated 18 October 1927, written by Lieutenant Colonel J. C. Pegram, Chief of the Geographic Section of the Military Intelligence Division to Colonel R. H. Thomas, Director of Map Publications in the Survey of India in Calcutta, apparently in response to an enquiry from the latter. Interestingly Pegram highlighted the extent to which a medium more durable than paper was a necessity when the constant use, repeated folding and effect of the elements quickly rendered paper maps unusable in the field. He indicated that their engineers were currently addressing the problem of printing maps on cloth, were improving their techniques and getting good results, although he offered no technical details to support this statement. The challenge of printing on fabric was essentially that the cloth had to be held taut during the printing process so that the image would not be distorted.

This map, printed on cloth, covers part of northwestern Georgia and adjacent Alabama to the west of Atlanta. It is annotated in blue pencil in the upper margin: ‘Specimen of field maps used in Sherman’s campaigns, 1864’.

Detail from this map.

Detail from Ordnance Survey one inch map of the Lake District (Keswick), printed on silk and dating from 1891.

The flexibility and durability of fabric, both silk and linen, as a medium for military maps had clearly long been recognized, a fact that had been reflected in the UK Government’s report of the War Office Committee tasked in the closing decade of the nineteenth century to consider the precise form of the military map of the UK. The Committee made frequent mention in its Report, published in 1892, and throughout the minutes of evidence, to the superior durability of linen over paper as a material on which maps could be printed for use in the field. Almost certainly related to the Committee’s work, although not acknowledged as such, the Ordnance Survey was simultaneously printing some of its one inch series of the Lake District on silk. Copies of two sheets, Ambleside and Keswick, are known to exist in a private collection and they are dated 1891. Ordnance Survey was still, at that time, staffed at senior levels by sapper officers from the Corps of Royal Engineers, so it is more than likely that they would have been called on by the War Office to do prototype printing experiments for military purposes. It is, however, notable that no mention of this work appears in the definitive history of the Ordnance Survey which concentrates rather on the work of the Dorington Committee which was taking place at the same time, charged with looking at the state of Ordnance Survey mapping after considerable public disquiet had been expressed.

With hindsight, it becomes very clear that the knowledge and capability to print maps on silk existed in the UK at the time of World War II and that the military had for centuries recognized the value of fabric maps, whether silk or linen, in terms of their durability and flexibility. Hutton’s search and ultimate decision to produce maps on silk might have been made more promptly and with far less effort and cost had he spoken to the military map-makers. Certainly both the Directorate of Military Survey (D.Survey), the principal military mapping organization, and the Ordnance Survey doubtless had the expertise but, for unknown reasons, they were apparently never consulted by Hutton, who preferred rather to approach commercial printers, paper manufacturers and silk processors. This is rather surprising, bearing in mind the covert nature of MI9’s activities and the secrecy which surrounded every aspect of their work, not least the mapping programme. It does, however, largely explain why MI9 paid little attention in their map production programme to the finer points of cartography and the standard techniques of identifying the maps they produced, as will be outlined in the next chapter.