Surveying Empires
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The Surveying Empires project has involved fieldwork undertaken in the hinterland of Kolkata (West Bengal) during 2016-2017. This fieldwork was made possible thanks to a grant from the British Academy, as well as institutional support from Queen’s University Belfast and the University of Calcutta. The Bodleian Library (University of Oxford) generously provided copies of historic Survey of India maps for the project.

Map of Bhola
Extract of Survey of India 1:125,000 scale (‘half-inch’) sheet (79B NW) showing the location of Bhola Tower Station (TS).
Map image kindly supplied by Bodleian Library, University of Oxford.

Using written accounts and historic maps to first identify the locations of GTS towers, GNSS technologies and Geographical Information Systems (GIS) then enabled the sites of towers to be located on the ground. While some towers were found to have survived, others had completely disappeared as monuments in the landscape, yet in all cases, whether standing or not, the fieldwork revealed that the GTS towers continue to have a presence in the minds and memories of local communities.

Surveying Empires fieldwork was undertaken in three phases starting with a Reconnaissance Phase in November 2016, followed by two Survey Phases, in January 2017 and March 2017. The following narrative provides a short account of the field-survey work for each of these three phases, as a record of the process.

Modern Image of Bhola Tower
Modern aerial image of Bhola Tower Station, surrounded by farmland.

Reconnaissance Phase, November 2016
With no previous survey of the condition of GTS towers available, the project’s initial task was to draw up a list of tower stations in the Kolkata region, and derive latitude and longitude positions for their locations for use in the field.

GTS Heritage site

Historic 1920s Survey of India (SoI) maps of 1:125,000 scale mark GTS trigonometrical stations as a triangle with a central dot, and from these maps a list of 21 trigonometrical stations was compiled for map sheets D10 (44) 079B NW, SE, SW and NE. The 079B SE sheet has no GTS stations marked, as the area it covers was not traversed by a GTS triangulation series. For the NW, NE, and SW sheets of 079B, a survey area of circa 60km was defined around Kolkata, and the locations of stations for ground-survey plotted out using Google Earth. This provided a basis for ground identification of tower sites derived from the historic 1:125k SoI mapping.

For the reconnaissance phase, four recorded GTS towers all located within Kolkata were chosen, primarily to gauge the logistics of travel and site conditions within the conurbation area, as well as to assess the sites for digital-survey using Structure from Motion (SfM) technologies of 3D image capture. Two rurally-located sites to the NW of the city were also selected for scoping the field-survey.

Barrackpore Trunk
James Prinsep’s sketch of the Barrackpore Trunk Road baseline being set out under George Everest’s instruction in 1830, with Everest-type tower station complete with observers positioned on the platform at the tower’s apex.
Image via Wikimedia Commons.

These six reconnaissance survey sites are:

  • Bhola
  • Sukchar
  • Nibria
  • Noada
  • Rishi
  • Settan

Of these Sukchar and Rishi are stations located on the Barrackpore Trunk Road in northern Kolkata and were the two terminal towers for Everest’s Calcutta baseline of 1829. These towers are in the custodianship of the Public Works Department (PWD) of Kolkata municipality. Noada is located near the Barrackpore Trunk Road in an area of housing. All three are east of the Hooghly River, while to the west in Hooghly itself is another tower located in a built-up area, Nibria. Both Nibria and Noada are former semaphore towers of cylindrical type whereas Sukchar and Rishi are both of the Everest model.

The search for Settan, in the area of Dwarbasini, 60km north of Kolkata, initially proved eliusive, but with local enquiry gradually the site was narrowed down and located. Enquiries made locally also began to yield interesting accounts about the tower at Settan, which is no longer standing. These encounters made it clear that the project ought to include ethnographic surveys for the tower sites, and not just evaluation and recording of the physical fabric of the towers. The tower at Bhola, west of Singur and nearby to the Kamarkundu railway station, is still extant, and initial inspection suggested it to be a suitable candidate for SfM recording.

The research team involved in Reconnaissance Phase fieldwork included Keith Lilley, Satish Kumar, Bishnupriya Basak, Sharmistha Chatterjee and Rajat Sanyal.

First Survey Phase, January 2017
With the Reconnaissance Phase fieldwork complete a group of 11 tower station sites were selected for closer field-inspection, undertaken in January 2017 by the entire project team. This fieldwork comprised both ethnographic and fabric survey. The GTS towers surveyed in the First Phase are:

  • Berghom
  • Bhola
  • Bira
  • Dilakas
  • Máyápur
  • Nibria
  • Pokpari
  • Rishi
  • Samalia
  • Sarisá
  • Simahat
  • Sukchar
Children visiting the Somalian GTS Tower   The Somalian Community
Somalia GTS tower, community interest and comparing maps. Photographs by S. Kumar, January 2017.

Pokpari and Máyápur both proved elusive despite much local enquiry. Known locally as Haldarpukur, the Samalia GTS station was located near Rasapunja and accessed by auto rickshaw from the Thakurpukur – Bibirhat road. Much local interest was encountered at this site, which is in a small village where the tower was found standing but in a precarious condition. The settlement of Sarisá, to the south of Samalia, also yielded local interest in the tower site, though there the station is no longer extant.

A day of surveying along the East Calcutta Longitudinal Series to the east of the city yielded no standing remains of the towers of Bira and Berghom, though local enquiry enabled the team to locate the sites of the towers firmly and record these. The Simahat tower site proved elusive in fading light, however.

The SfM equiment was successfully used at Sukchar, Rishi and at Nibria stations in the Kolkata metropolitan area. Similarly at Bhola, near Singur, where the survey team were also invited to join local people to share in a communal meal as part of their festival which took place in the field adjoining the tower, on Sunday January 14th 2017. From Bhola, the team drove to Dilakas, and located the station in the village of the same name, still standing but with some damage to the fabric. Much local interest was encountered here too, but the site was too restricted to attempt  a 3D SfM survey of the tower.

Dilakas Tower GTS Tower and a road People phtographing a GTS Tower
Dilakas GTS station (left), Bhola GTS station (centre), and Sukchar GTS station (right).
The SfM survey at Sukchar was hampered by traffic and by strong contrasting lighting conditions.
At Bhola, vegetation close to the tower presented difficulties for image capture,
while at Dilakas it was the close proximity of buildings that precluded SfM survey. 

Photographs by K. Lilley, January 2017.

For the First Survey Phase of fieldwork, Satish Kumar and Bishnupriya Basak led the ethnographic work, while Keith Lilley and Rajat Sanyal led the fabric surveys – supported in the field by Siobhán McDermott and Sharmistha Chatterjee.

Part of the Bira Tower
Brick recovered from the site of the demolished GTS station at Bira.
Photo: K. Lilley, January 2017

The fabric survey comprised digital photography, including SfM methods, the measurement of station structures—including dimensions of base of tower, doorways, and bricks—the tower’s positional coordinates (using GNSS), and note-taking/recording. The ethnographic survey work involved digital voice-recording of local people, particularly those with living memories of the standing structures (before they were destroyed) and also stories and accounts about the towers. Ethnographic interviews included information about the respondent, such as their name and age, as well as their permission to make the recording.

Second Survey Phase, March 2017
With the second phase of fieldwork the aim was to locate and evaluate the remaining GTS tower station sites within the survey area, principally to the south-west of Kolkata, on the west banks of the Hooghly River, and the stations forming part of the East Coast Series. The opportunity was also taken to revisit the site of Settan, as well as explore further to the north-west of Kolkata, in the region of Tarkeshwar, and locate the site of the GTS tower station of Aknapur. The Second Survey Phase comprised the following sites:

  • Aknapur
  • Baniban
  • Dhaja
  • Mirzapur
  • Settan

Aknapur Tower
Aknapur GTS tower station.
Photo: K Lilley (March 2017)

This second survey phase brought the total number of sites surveyed to 18 for 079B sheets NW, NE and SW, leaving three sites in West Bengal (Brul, Natsal and Noráda) unvisited—and one in Bangladesh (Piprāgāchhi)—due to logistical reasons. The Baniban, Dhaja and Mirzapur stations were all located along the west banks of the Hooghly River but none survived on the ground, while Settan—visited in the Reconnaissance Phase in November 1916—was revisited to follow-up local contacts and undertake ethnographic survey work. The site of Aknapur provided a fitting conclusion to the project fieldwork, a magnificent tower, slightly different in its design compared to those others found in the region, still standing proud surrounded by the fields and farms.

Overall, the fieldwork and search for the remains of 21 GTS tower stations in and around Kolkata proved that the sites are locatable through a combination of historical research using maps and written accounts, modern aerial imagery and navigation technologies (GNSS), and local enquiry, all helped by a very willing and expert driver, traversing roads that many would not wish to drive along, as well as an excellent project team whose expertise combined geographical knowledge and archaeological skills, and whose collective experience of decades of working in the field proved invaluable.

Most of all, the fieldwork yielded three key findings: (1) that the GTS tower stations remain important in both the collective and individual memories of local communities; (2) that fabric survey of the GTS towers reveals techniques of construction and ideas about their design; and (3) acting NOW is crucial to conserve examples of the GTS towers in West Bengal before they are lost forever.

3D Scan of a GTS Tower 3D Scan of a GTS Tower window
3D visualisations of the GTS tower at Nibria based upon SfM survey by Sharmistha Chatterjee and Siobhán McDermott.