Preliminary investigation: Marine archaeology of the anchorage and waters off Tranquebar in India

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Index

Preliminary Studies..............................................   2
Investigation....................................................   3
Measurements with the proton magnetometer in waters off Tranquebar  5
Dives............................................................   7
Interview with local fishermen...................................   8
Investigation of masulas and wooden anchors......................   9
Conclusion.......................................................  11

Appendix I     Plan for marine archaeological investigation of the anchorage at Tranquebar
Appendix II    Merchant ships lost on their way to and from Tranquebar and East India
Appendix III   Wreck location with the aqua scan MC5
Appendix IV   Measurements of a masula and wooden anchors

Marine archaeological study of the anchorage and waters off Tranquebar in
India - carried out from 4 to 10 February 2007

The purpose of the investigation was to locate shipwrecks and other objects on the seabed or buried off the coast of Tranquebar. The investigation is to be used as a preliminary study, which may lead to a larger survey/excavation with Danish and Indian marine archaeologists.

The investigation was initiated by The Tranquebar Association and carried out by diver Gert Normann Andersen from JD-Contractor ApS, and technician Kim Schmidt from HV-Elektro. The Tranquebar Association contacted locals for the use of vessels, fishermen and divers.

Gert Normann Andersen and Kim Schmidt also represent "Stranding museum St. George" (Ringkøbing / Holstebro Museums) in Thorsminde which is responsible for marine archaeology along the West Coast of Jutland and its fjords.
This rapport will be available on the web pages for Strandingsmuseum St. George
(www.strandingsmuseum.dk ) and The Tranquebar Association (www.trankebar.net/).

A plan for the preliminary investigations can be seen in appendix I
The primary investigation went largely according to plan. (Comments and deviations are written in italics).

Preliminary Studies

Before departure from Denmark, a literature search of relevant Danish and foreign literature was carried out to get an idea of what can be expected to lie in the coastal waters off Tranquebar. (See appendix II)

Lawrence V. Mott from Syddansk University wrote, in 2005, a rapport about the possibilities of establishing a marine archaeological school (Summer Field School) in Tranquebar. The rapport describes the conditions, and earlier marine investigations in the area. One discovery is a Dutch ship from the 19th century, which lies at a depth of 23 metres about 5 km north of Tranquebar. The rapport also describes two circular anomalies near Fort Dansborg.

On the official sea charts from the area, there is a wreck marked approx. 2.5 nautical miles from land and approx. 6 nautical miles north of Fort Dansborg at a position of 11 07 191 N and 079 54 016 E.

Appendix II contains a list of ships belonging to the Danish East India Company that have been lost on journeys to East India. There is also a selection of English and Dutch ships that have been lost along The Coromandel Coast. The number of lost ships is in reality much greater than listed, as the lists only include certain periods, and ships from Spain, Portugal, France and many other countries are not mentioned. Also local and Asian vessels that have been lost in the area are not mentioned. A list of literature concerning ships and navigation around India can be found at the end of the appendix.

As a point of interest it should be mentioned that many of the foreign ships that have been lost had large fortunes onboard. Generally the Danish and other foreign ships had large valuable cargoes from their homeports. Especially iron and lead were good trading materials in India, and these were used as ballast during the outward voyage. There were often chests with coins and gold- and silver bars that were used to establish and maintain the colonies. Money was also needed to buy sought after goods that could be sold for huge profits in Europe. The ships could also carry crates with weapons, knives, binoculars and other European articles.

Homeward bound the ships were often loaded with silk, dyes, sugar, tea and spices; especially pepper, which could be sold in Europe for up to 30 times the purchase price in India. Sometimes the ships carried polished gemstones, ivory and gold from Bengal and other Asian countries.

In extracts about lost ships from the British East India Company, there is also mention of valuable items. In the area off Tranquebar there is believed to be the remains of the English frigate Madras which sunk with a cargo of coins in 1688. Also the money chest from the Evangelical-Lutheran mission which was lost at sea at Tranquebar during loading in the summer of 1708 should still be in the area. Of Danish ships, it is expected to find remains of the ships that were broken up at Tranquebar. Other Danish ships that were lost along the Coromandel Coast were lost at other locations both north and south of Tranquebar.

It might also be possible to find remains of masulas, transport boats, which were used to transport goods from the ships to the shore.

Investigation

Considerations for our investigations will be based on a systematic search using a proton magnetometer. This will give us the most accurate positions of shipwrecks and other large objects at the bottom of the sea.

The equipment is comprised of a probe that is dragged in an underwater cable approx. 20 metres behind the workboat. The cable is connected with an instrument on board the boat where search parameters are set and all the signals can be read (see Appendix III).

The proton magnetometer measures the magnetic field in an area. Magnetic fields differ around the world; therefore the equipment has to be calibrated by the manufacturer to the specific location. When iron is located on the seabed, the magnetic field will be distorted close to it.

All old shipwrecks contain iron. These include numerous things from the many iron rivets; that the wooden planks over the whole ship were spiked with, to the anchor, iron fastenings, iron ballast, canons, weapons and other equipment on board. Shipwrecks, both old and new, can therefore easily be found using a proton magnetometer. Even individual items the size of an anchor or iron canon will give a good signal, though the intensity of the signal will not be is as strong as with a whole wreck. In this way it is easy to tell the difference between a large wreck and an individual ferrous object.

The bottom of an old wooden shipwreck of a reasonable size can normally be measured at a distance of about 100 meters on each side of the probe. Most of the old ships that bounty hunters have located around the world have been with a proton magnetometer.

Most investigations were carried out from a small open fishing boat. Here is a picture of Gert Normann with the captain and an assistant off Fort Dansborg. The local fishermen are very good sailors and were a great help with our investigations.

Measurements with the proton magnetometer in waters off Tranquebar

The first couple of days we concentrated on scanning the seabed near the old town of Tranquebar at Fort Dansborg. All readings were logged as geographical coordinates with the aid of a GPS-receiver.

After an occasional sandbank and troughs in the area of the surf, the water became steadily deeper. Close to the coast the seabed was just sand, though further out there are increasing amounts of clay sediments. Gradually the amount of sand decreased leaving just silt.

First we registered all the variations and anomalies in an area of 1200 meters along the coast and approx. 1500 meters out to sea. The research area was then increased. We made a circa 600 metre broad belt approx. 5 km to the north and approx. 6 km to the south of our initial investigation point near the town. It was in this area that there was the greatest probability of finding wrecks from beached ships. The distance from land to the search area was calculated from measurements of coastal erosion over the past 200 years.

Results showed that there were surprisingly few signals registered in the expanded area compared to what we normally find along the West Coast of Jutland.

Approx. 1.8 nautical miles north of Tranquebar at position 11 03 287 N and 079 51 931 E, there was an area with signals that was large enough that it could be a small shipwreck.

All other signals were found off Tranquebar in a belt from 130 to 380 metres out from the current coastline; in an area where the dangerous breakers were found in the period from the 17th to 19th century.

Signals that were registered off Tranquebar:

The shore by the red outer fort wall outside Dansborg was measured at position 11 01 398 N and 079 51 380 E.
The stairs on the East Side of Fort Dansborg was measured at position 11 01 434 N and 079 51 371 E.

1)	11 01 687 N and 079 51 464 E = strong signals over a small area.
2)	11 01 509 N and 079 51 601 E = weak signals.
3)	11 01 452 N and 079 51 529 E = many weak signals.
4)	11 01 398 N and 079 51 573 E = weak signals.
5)	11 01 365 N and 079 51 504 E = weak signals.
6)	11 01 331 N and 079 51 552 E = two weak signals.
7)	11 01 241 N and 079 51 517 E = many weak signals.
8)	11 01 113 N and 079 51 483 E = good signals.

All of the above signals had a size relating to those expected by an iron anchor or a canon. None of the results were large enough to be interpreted as a whole shipwreck.

All positions are given according to the WGS 84 system.

Where the ships were anchored for loading and unloading, there were no signals. Therefore no ship was sunk at the anchorage off Tranquebar, and only small artefacts or rubbish must have been thrown from ships in this area. A lost anchor or canon would undoubtedly have given a signal on the proton magnetometer.

There can be many layers of debris on the seabed near the anchorage, which are not registered by the proton magnetometer. Typical layers of debris at the anchorage include waterlogged beams, potsherd, bottles, clay pipes and other non-ferrous waste.

A section of a chart off Tranquebar Some of the search tracks and all the readings from the magnetometer are drawn onto the map. The river is misleading, as the subsidiary into the sea is not so broad. The mouth of the river is just visible in the southerly turning point of the lines drawn.

The search was irregular. This was due to the fishing nets and other boats in the water. Subsequently the gaps in the search area were investigated when there was room. This resulted in criss-crossing the search area in order to reach the last areas to be investigated.

Dives

It would be best to dive and inspect all the positions, which gave a reading and where locals think there is something on the seabed. Though due to the rough and murky sea, and the large amounts of fishing nets in the area, it was not possible to carry out a safe dive.

Most of the year there are high waves and surf with very murky waters around Tranquebar.
After talking to a local Indian diver, we learnt that in February and March there was a good chance for calm and clear water along the coast. Even though we were in the area in February, the conditions were not good enough for us to dive. The best three days the waves were between 0.5 and 1 metre high, and the last two days the waves reached between 1.5 and 2.5 metres high. Every day the water was murky, even away from the coast. Further out visibility reached a couple of meters on the surface, but already at a depth of 2-3 metres the water became totally thick. During a dive, Kim Schmidt reached the seabed at a depth of 7 metres in total darkness. Afterwards, he described the water like soup.

Waves, surf and murky water are normal conditions around Tranquebar. The Indian word for Tranquebar is Tharangambadi which means "place of the singing waves". This comes from the sound of the constant high surf.

The local offshore diving boat, where we carried out searches and tried to dive. The boat is equipped with modern diving equipment and is crewed by 11 divers and sailors. It is used to supply an offshore drilling rig 8-10 nautical miles south east of Tranquebar.

Kim Schmidt prepared to dive, but the underwater investigation was cancelled because of the rough and murky water (photo: Bent Christensen).

Interview with local fishermen

We talked to the local fishermen about where they thought there could be old shipwrecks, and where their equipment caught on something on the seabed.

From our interviews, we were able to get a GPS-position of a wreck which lay 6.8 nautical miles south east of Tranquebar at a depth of approx. 26 meters at 10 58 143 N and 079 57 470 E. This position was only registered, not investigated by a diver, because it was far from our investigation area, and the time was short.

Fishermen also reported a wreck close to the coast near a village approx. 6 km south of Tranquebar. This area was investigated with the proton magnetometer though no signal was registered. Due to high waves and a defective echo sounder, on the Indian diving ship we used that day, the skipper would not venture closer to the coast than 600 metres. It is still possible that there is a wreck in the area, even though our equipment did not register anything that day.

South of Dansborg is an area where fishermen do not go; at a depth of 4 meters they maintain it is an evil place, where fishing tackle or worse can be lost. As we do not believe in evil spirits, we think it is a wreck or some other hindrance on the seabed, which causes the tackle to get stuck.

Later, we probed the area with the proton magnetometer, and instantly the probe caught on something underwater. This scared the two Indians on board, so they jumped away from the cable. Kim took over the cable and felt that the cable was caught on something flexible on the seabed. After a while, the probe freed itself and we managed to haul it onboard. When we sailed over the place, the echo sounder showed a moving shadow a couple of metres above the seabed. We concluded it was a mass of fishing net, held on the seabed by some large stones. It could not be a wreck because the proton magnetometer did not register any metal. Due to bad visibility and rough water it was too dangerous to dive and investigate the area the next day. There was a risk that the diver would become entwined in the large amounts of lost fishing nets.

Even though we are not superstitious, we could not avoid thinking about the story of the priest Christen Pedersen Storm. According to some, the bad places in the water are due to the cruel priest haunting the place. The priest was at the start of the 17th century sentenced to death for his crimes. He was drowned: first by being tied in a sack with two large stones and then thrown alive into the sea off Dansborg.

Investigation of masulas and wooden anchors

A fascinating aspect of India is that Old Danish traditions from throughout history are still present in everyday life i.e. grinding mills which were used in the Stone Age are still used in India today. Also boats built like in the Bronze Age, brickyards from the 17th century, and agriculture and fishing tackle from the 19th century. India also has a modern side with modern machinery, tools, electronics and computers.

We had to days while we waited for our equipment. These were used to investigate a masula, a traditional type of boat, which we wanted to find and measure together with traditional wooden and stone anchors.

A masula is a particular type of boat where the planks and frames are bound with coir in stead of nails (exactly as was used in Denmark in the Bronze Age). It was also this type of boat, which were used to load and unload frigates at anchorages along the Indian East coast throughout history. They were also used to load and unload Danish ships.

When Gert Normann was in Tranquebar In 1995 he saw a masula, maybe the last original masula on the coast. A year later he wanted to document and measure the boat, but the locals said that the masula has been totally destroyed by the waves and there was nothing left.

Karin Knudsen informed us of reports of a masula in a village south of the river in Kirala district. Together with Bent Christiansen, we visited the place and found the masula inland, close to the memorial for the victims of the tsunami. Unfortunately it was not an old masula, but a newer version with iron staples instead of the coir binding. Also the planks were not as broad as in the old masulas, but the size and form were nearly the same. The masula was therefore measured, videoed and photographed (see appendix IV).

In the current fishing town of Tranquebar we found various wooden and stone anchors which were measured and photographed (see appendix IV).

For a literature list on Indian boats see appendix IV.

Tranquebar 1995 Maybe the last original masula on the coast: photo Gert NormannA masula (masulah or masoola) is an Indian word for a type of boat where the planks are joined with coir of coconut fibres which cross over a wadding of the same material. This makes the boat flexible, so that the shock on taking the beach through surf is much reduced.

A modern masula, which is found in fishing villages south of Tranquebar. The planks are not as broad, and instead of coir, the boat is joined with steel staples. This type of boat is less resistant in the surf, and is less suited to landing along the open coast than the old style masula. This type of boat is now replaced by glass fibre boats. (photo: Bent Christensen)

A wooden anchor with stone weight. These are still used today by local fishermen in Tranquebar, though it is only a matter of time before these wooden anchors are replaced by anchors with an iron dredge. (photo: Bent Christensen).

Conclusion

After analysing the readings from the magnetometer in the area off Tranquebar, we could not find signs of a shipwreck in the search area, not even something that would have the size of a piece of wreckage floor from the ships broken up in the area.

In the anchorage there was found layers with debris and objects fallen from ships, mostly kitchen waste, potsherd, clay pipes and small objects, though there was not found metal objects of a size which were registered by the proton magnetometer.

We got a series of readings in a belt from 130 to 380 metres from the current coastline, though none of these readings had a size that indicated a large shipwreck. The signals were of a size corresponding to a single piece of iron, the size of an anchor or canon, or pieces of a cargo containing iron. It could be something that was lost when a smaller boat capsized or sunk. The wreck of a masula can not be measured as these were built of wood and sewed with coir, so were without iron.

Referring to the coastline of Trellund's map from 1733 we can see that the belt with readings corresponds to the surf zone in the 17th and 18th century. It was here that small transport boats and masulas were most at risk of capsize, sinking or being wrecked.

It is interesting that we only got readings in this belt off the old town of Tranquebar and not in the kilometres long passages north and south of the town, which pass through several fishing villages. This indicates that the signals recorded are probably due to objects lost in conjunction with activities off Tranquebar in colonial times.

We expected to get readings from pieces of ships that according to history were broken up off Tranquebar; though the powerful waves that come up the coast may have swept the pieces of wreckage up on dry land as they became dislodged and free of their cargoes.

The positions located by the photon magnetometer need to be investigated by a diver when conditions allow. The greatest chance for calm water and visibility is in February and March, though it cannot be taken for granted, so there needs to be a long time period set aside in these two months in order to guarantee good diving conditions.

It can not be expected that a diver, even under good conditions, can find a wreck or objects from the 17th or 18th century lying on the seabed. All the wooden parts exposed to the warm water would have been quickly decomposed by woodworm and other plant consuming organisms eating away at them. Only parts of the wreck that are buried in the oxygen free layer under the seabed would be well preserved. Heavy items such as iron and other metals that are non- perishable will quickly sink into the seabed due to currents and wave movements, and become covered with sand and sediment.

The strength of the proton magnetometer is that it can measure shipwrecks and other ferrous objects hidden in the seabed.
If there is to be a successful marine archaeological discovery off Tranquebar, it has to be done during the best season. The sand and sediment needs to be systematically removed with a suction pump in a controlled excavation over the investigation area.

18. February 2007

Gert Normann Andersen
gna@jdcon.dk
JD-Contractor ApS
www.jdcon.com

and

Kim Schmidt
hv-elektro@hv-elektro.dk