|The Surveying Empires research project follows in Everest’s footsteps…
With the approaching bicentenary marking when George Everest first began his work with the Great Trigonometrical Survey (GTS) of India, the time is right to raise greater awareness and appreciation of the cultural legacies of the GTS, including its surviving monuments and infrastructure.
Undertaking fieldwork on GTS built heritage in India, a team of geographers and archaeologists from Queen’s University Belfast (UK) and the University of Calcutta (India) have used 21st-century digital-survey methods to record, map and analyse the structures used by the GTS under George Everest, two hundred years ago. As cultural heritage of international significance, collectively these GTS structures have particular ‘group value’, and as a result of Surveying Empires research it is clear that surviving GTS survey towers in West Bengal represent ‘world heritage in danger’.
Already many GTS towers have been lost forever from the landscape, and the few examples that do survive are now in serious risk of ruin and damage. Action is urgently required to ensure these iconic monuments are protected and valued by conservation and heritage organisations and professions in India and the UK. To record GTS built heritage before it is too late, and to widen appreciation of the cultural legacies of the mapping of India, further research is needed.
The project particularly sought to digitally document the survey towers of the GTS as part of a process evaluating the standing remains and recording these for analysis and interpretation. While the history of the GTS is well-told by historians and geographers using archival and colonial records, the ‘material cultures’ of the GTS have on the whole been overlooked by scholars. Surveying Empires is an attempt to redress this by focusing especially on the material impacts the GTS had on localities and landscapes in West Bengal, using field-survey techniques to examine the structures built by the GTS, and the enduring cultural impacts of the GTS, using ethnographic surveys and interviews conducted with local people living around the GTS station sites.
Ethnography reveals the importance of the ‘intangible’ heritage of the GTS in West Bengal. For those sites where stories about the GTS towers were collected, a summary is offered here highlighting how local people relate to this ‘living heritage’ of the GTS. A common motif emerged from the stories told by local people about the GTS towers—described as girija—actually meaning ‘church’ in Bengali—as mechanisms of military surveillance, built by the colonial state at strategic points in the landscape to ward off enemies. The legacies of the GTS therefore go beyond the visible, ‘tangible’ heritage of the towers themselves.
More information about the field methods used in the project can be found in the Fieldwork section of this web-site.
Kolkata (Calcutta) formed the institutional base for the GTS under George Everest in the 1820s and 1830s, and has an important role in the organisation and development of the GTS in India as a whole. Everest set up one of the ‘baselines’ for the GTS in Kolkata in 1831, the end points of which were marked by two terminal survey ‘stations’, 75-foot towers which apparently Everest ‘was specially pleased with’, and which linked then to a wider network (‘series’) of trigonometrical chains that spanned the entire sub-continent. A map of the whole GTS trigonometrical network of India is to be found here.
From the Kolkata baseline, four series of trigonometrical chains struck out across the landscape, to the north, south, east and west. In this lower-lying and relatively flat region of eastern India, it was necessary to build brick towers to provide a stable elevated platform from which to undertake the trigonometrical survey-work. Surveying Empires aimed to find examples of these historic survey towers—the stations used in these four trigonometrical series—and from this compare their structures and designs in order to gain insights into the methods and techniques used in their construction and use. The findings of the project’s survey-work are set out in the GTS Stations pages of the web-site.
In essence, the design of the GTS survey towers, although conforming to a ‘model’ of Everest’s making, varies both within and between the trigonometrical series present in West Bengal. Some towers were rebuilt in the 1850s and 1860s on the same sites as earlier towers of the 1820s and 1830s, while others reused a series of semaphore stations constructed in the previous decade, in the 1810s, to link Kolkata with Banaras. The latter structures are of cylindrical form, while the ‘Everest type’ of survey tower is a truncated-pyramid structure, of square plan, gradually tapering inwards with height, and usually built around 70-80 feet tall (c.30m), in brick but originally with a rendered outer surface. Both types are ‘hollow’ towers and once contained an internal ladder and staging in order to gain access to the upper platform of the tower where the surveying instrument—the theodolite—was set up and from where observations were made to neighbouring stations. Not all GTS stations were built as lofty towers however, as some were lower in height, and others were ‘pillars’. Stations were al so placed on existing buildings and structures.
More detailed study of the GTS tower stations is required NOW, before greater losses of fabric occur and before local stories about the towers disappear forever from living memory. Surveying Empires represents a first step towards a wider and more ambitious field-study of the tangible and intangible heritage of the GTS in India. For more information please contact us – see Team page for details.
Sukchar GTS tower station of ‘Everest type’, memorialised by the Public Works Department (PWD) of Kolkata with an inscription in English (and Hindi on the opposite façade). Photo: K Lilley, January 2017
Description of trigonometrical stations of the East Calcutta Longitudinal Series:
The Principal Stations of this Series are either perforated masonry pillars or hollow rectangular towers. The perforated masonry pillars, eleven in number, are rectangular (about 7 feet square) at base, and circular (about 3| feet in diameter) at top, with one mark-stone at the ground level and another from 2 to 4 feet below: of these, for the accommodation of the observatory tent, the first 5 pillars, at the western extremity of the Series, are surrounded by solid towers of sun dried bricks and mud cement, 21 feet by 18 feet at base and 11 feet by 11 feet at top, while the others had temporary scaffolding platforms erected around them. As regards the hollow rectangular towers, there are 29 of this construction, externally 17 feet by 14 feet at base and 14 feet by 11 feet at top, with circular perforated masonry pillars— 31 feet in diameter and 3 feet in height—resting on beams let into two of the opposite walls near the summit of the towers, while the platforms for the observer, if not of a temporary nature, rest on beams which bear on the two other walls: a mark-stone is placed in the ground floor and another below it. In all perforated pillars and hollow towers access to the ground level mark is obtained by a passage constructed for the purpose.
Extract from ‘Synoptical Volume XXI, G.T. Survey of India. The East Calcutta Longitudinal Series & The Eastern Frontier Series’ (published 1883 by the GTS)
Samalia GTS tower station of the ‘Everest type’, partially collapsed.
Photo: K. Lilley, January 2017
Ethnography in action: Bishnupriya talking to local people about the GTS tower at Bhola.
Photo: S. Kumar, January 2017
Section of GTS Index map of 1870 for Calcutta and region, showing the four triangulation series converging on Calcutta, as well as the trigonometrical stations (shown as circles). Reproduced from: Wikimedia Commons
Dilakas GTS tower station of ‘semaphore type’, with some loss of fabric. Photo: K Lilley, January 2017
Elevation and plan of Everest-type tower station, from Everest’s Account of the Measurement of
Two Sections of the Meridional Arc of India (London, 1847).