Tagarchief: heritage

And then it was the last day…

We have spent the couple of days approximately 20 hours underwater, with each time effectively 25 minutes dive time at 24 metres. We have covered a large area and managed to map the site reasonably well. We go back with measurements, film and photo footages, drawings and observations. Now we have to put this all together to create a good site plan and to answer our scientific questions. We have it all and will thus be able to come up with a recommendation for the future, and perhaps a future excavation proposal, depending on the further analysis of the results. It’s all very exciting!

One thing is sure, we had a great time working together with the different groups. I would like to thank all of them, not only for the diving but also for all the discussions we had, the exchange of knowledge and all the fun. In the end, a beautiful project like this should be enjoyed, and we did with a smile even while making days from 5 o’clock to 23h.

So thank you, the team in Ramsgate:  Mark James, Alex Hildred, Dan Pascoe, Johan Opdebeeck, Pete Magowan, Mark Hobbs, Graham Scott, Paolo Croce, Thijs Coenen and Kester Keighley

The lovely Dan (Poppy) and Ben of our ship The Predator (project savers)

Alison James, Angela Middleton and Mark Dunkley from Historic England

Peter Holt for being our telephone hotline for Side Recorder

Peter Hamer for equipment maintenance and delivery

Pidge the cook

Kai Dieho the camera man

Willemien van de Langemheen and Debbie Hickman for the wonderful job they did to communicate the project to the outside world and to maintain contact with the press

And last but by no means least: Ken Welling, the licensee of the Rooswijk shipwreck, for sharing the enormous amount of information he gathered about the site with us, as Rex Cowan did, thank you both.

It was a huge success and let’s do it again!

Martijn Manders

Photo above: The team! From left to right: Martijn Manders, Thijs Coenen, Ben, Dan (Poppy), Peter Magowan, Mark Hobbs, Paolo Croce, Kai Dieho, Johan Opdebeeck, Mark James, Alison James, Alex Hildred, Dan Pascoe, Kester Keighley (missing: Graham Scott who took the photo!)

 

 

Continuing the Van Bosse research on Tarama: agreeing on future activities

The past few days were devoted to exploring the possibilities to learn more about the wreck Van Bosse which sank in 1857 off the coast of Tarama. By conducting several interviews with residents, who have been narrated stories about the wreck by their ancestors, but also with information from local books and archives we are able to develop scenarios about how the ship must have sunk after being leak bumped on the reef. This again helps us with the search for the wreck itself.

We have found objects, like an anchor, a bottle of gin, a huge chest and shards of major Chinese jars that may also have been on board the ship. But parts of the ship itself are still not found. Dr. Ikeda and Mr. Sasaki will focus their attention on this in November. Using a metal detector they will search the impact site, where most objects are found and everything in between will be swum and explored.

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The beach of Tarama at the spot where the Van Bosse ship presumably sank

At the same time they will continue to conduct interviews with the people of Tarama who know the stories about the wreck. An information project with the elementary school will be launched. In November, the children on the island can meet archaeologists and interview them for the project. In the Netherlands and Germany we will do further research into the archives.

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Meeting with the head of the island

The Van Bosse project is alive! It’s interesting and amazing to see how excited everyone is. The administration of the island would like to do more with the story and the wreck site. It would indeed give the particularly beautiful diving at Tarama an additional cultural and historical dimension. Then it becomes even more worthwhile to travel over here and visit this island paradise, voted one of the most beautiful municipalities of Japan.

Martijn Manders, maritime archaeologist / Head Maritime Programme RCE

Photo at the top: the highest point of the island, about 30 m, with a 15 / 16th century lighthouse

 

Searching underwater for the Van Bosse ship (1857)

A team of underwater archaeologists consisting of two members of the Japanese National Committee for Research and the Examination of Underwater Cultural Heritage Dr. Ikeda and Dr. Kimura, as well as mr. Sasaki from the National Museum of Kyushu and mr. Manders from the Cultural Heritage Agency of the Netherlands has arrived on Tarama island. This is one of the most Southwestern Islands of the Japanese archipelago, actually very close to Taiwan.

In November a Japanese team of professional archaeologists and sports divers associated with the only dive school on the island – Jaws 2 – will map and assess the site of the Van Bosse wreck and make it accessible for the sports divers who spend their holidays on the island. The visit now in August is mainly initiated as a start of the project about the Van Bosse shipwreck which includes also educational elements and archival research in several countries. The 22nd of August the team was welcomed by the department of education of the island that effectively is responsible for the management of this and other archaeological sites. They have assured us that all help in this is welcome. After this meeting we went to the dive shop to sort out our gears and then settled down in our condo which we share together.

The evening was used to discuss the possibilities to find elements of the wrecksite underwater and to pinpoint the exact place of wreckage, which is still not completely known. Dr. Kaneda wrote in 2001 an article ‘Historical Investigation concerning the Dutch Ship Van Bosse Wrecked Off the coast of the Tarama Islet’ and this article has also been discussed between the archaeologists in order to find out what the chances of finding wreckage are and what kind of research should be further conducted.

Van Bosse 2016 duik 1 (39) blog 2

The morning on the 23rd we were up early to go diving from the beach to the place where the ship according to accounts must have wrecked and where a fisherman has salvaged many pottery over the years. Indeed by walking on the beach we collected many pottery shards of different kinds. These are however mainly Chinese.

The coastal waters around the island Tarama are very shallow and abruptly become much deeper with here and there dangerous rocks ending just a few meters under the sea surface. For somebody who is not acquainted with these waters, it is a dangerous place. The underwater world, just at the edge of shallow and deep is however stunningly beautiful!

The second dive today was in deeper waters with the dive shop Jaws 2 and their ship. At 28 meters of depth, again on the edge of where the water gets very shallow and  near the place we had been diving in the morning, a considerable amount of pottery shards from large Chinese storage jars can be seen lying on the seabed. Were these used at the Van Bosse ship? It came from China…

Van Bosse 2016 duik 2 (19) blog 2

Also an enormous iron crate was discovered. Definitely something has happened here. The area however is large and the research in November should reveal the size of the site and maybe even also the location of impact: where the ship has hit the reef.

Tonight we will talk with an old fisherman. Let’s see if he can help us out.  Tomorrow, the 24th we are invited by the head of the island, similar to a mayor and in the afternoon we have a round up with the advisory board of the heritage of Tarama. Then up to Fukuoka for further talks at the Kyushu National Museum, our partner in shared heritage management.

Martijn Manders, maritime archaeologist/Head Maritime Programme RCE

Japanese – Dutch research on shipwreck Van Bosse about to begin

In August, the Cultural Heritage Agency of the Netherlands (RCE) is joining forces with the Kyushu National Museum to conduct an exploratory research on the Dutch shipwreck Van Bosse. The research focuses on exploring opportunities for mapping the Van Bosse and providing accessibility to the wreck for local sports divers. The project is a continuation of existing cooperation with Japan in the field of maritime archeology within the framework of Dutch Shared Cultural Heritage policy. The site of this Dutch wreck is already protected locally. The ship was built in Germany, but registered by the Dutch owner in Rotterdam.

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The ship Van Bosse was originally built in 1854 in Germany. The 665t big three master barque, which was employed by the Bonke & Co. Trading in Rotterdam was on its way from Shanghai to Singapore when it sank during a storm in 1857 at Tarama island, Okinawa prefecture. Luckily all 27 people on board survived, but before they could return to Batavia in the Dutch East Indies, people stayed several months in Okinawa and integrated into the local community.

The story of the sinking of the Van Bosse and the interaction of the people of Tarama with the crew of the ship are recorded in detail. It gives us a good insight into the history of the Ryukyu Kingdom and the relationship that it had with foreign powers at a time when the self-isolationism of Japan had just been lifted. It is striking that until few years ago nobody knew exactly what ship it was, although the story of the sinking of the ship was well known. We know it now, thanks to extensive research in Dutch archives.

The Van Bosse shipwreck is registered as a Village Historic Site (オ ラ ン ダ 船 遭難 の 地: Oranda-sen Sonan no Chi ~ Site of Dutch ship wreck). It lies on a reef at depths ranging from a few meters to about 30 meters. Over the years, an iron anchor was lifted, which is on display in a local museum, and several other finds such as a complete Lucas Bols gin bottle and some salvaged porcelain shards.

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However, there’s more to be found. Despite the protected status of the ship an archeological significance assessment of the wreck site has not yet been made. This will take place this autumn and is having its official start now in August, with a first joint visit to the site. Ultimately this will lead to a management plan for the site in which all interests should be taken into account. The Van Bosse wreck is already dived regularly by sport divers. A local dive shop has voluntarily undertaken protection of the site. The local authorities are working on an active promotion. The aim is to use the wreck to attract more recreational divers to the island. But what measures are necessary to facilitate an intensive visit of sports divers? How, for example, can the remains underwater be protected while still visible and accessible to visitors? And there is need for more information about the site to allow divers to fully experience the wreck and its history when they are underwater.

In August Dr. Ikeda from the University of Okinawa, Dr. Jun Kimura of the Tokai University in Tokyo (with students), Randy Sasaki of the Kyushu National Museum and Martijn Manders (RCE)  will officially start the project. In November, the Japanese partners will conduct follow-up research historical research in the Netherlands and Germany will be coordinated by the RCE.

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Late August the World Archaeological Congress (WAC http://wac8.org/) will be held in Kyoto, Japan. As part of the Japanese – Dutch cooperation Martijn Manders and Yoshihi Akashi will represent the Fukuoka prefecture and chair the session ‘Global Perspectives on Underwater Cultural Heritage Management’. The presentations will elaborate on universal values of the underwater cultural heritage management, what needs to be improved in management and the way countries can cooperate in the protection of underwater cultural heritage. This fits exactly with the way the research on the Van Bosse shipwreck is implemented: a collaboration between various parties in the country where the ship sank, Japan, and the country of origin, the Netherlands.

Martijn Manders, maritime archaeologist/Head Maritime Programme RCE

Nederlanders overzee in Brazilië: met een dikke scheepshuid op reis

Brazilië is tussen 1630 en 1654 voor een deel bezet geweest door Nederland. Mensen, goederen en wapens moesten worden ingevoerd met schepen vanuit Europa en de Westkust van Afrika om de suikerplantages aan de gang te houden en te beschermen tegen indringers. De lange tocht door warme tropische wateren was niet goed voor de huid van de houten zeilschepen.
Begroeiing zorgde voor een vertraging in de reis maar erger nog was de aantasting van de planken door de paalworm (Teredo navalis). Binnen zeer korte tijd kon stevig eikenhout verpulverd worden door dit schelpdiertje dat lange tunnels door het hout eet en zich erin nestelt. Columbus had hier einde 15de eeuw al grote problemen mee en vele zeelieden op weg naar (Zuid-) Amerika na hem leden hierdoor schipbreuk. Geen prettig vooruitzicht, zeker niet wanneer de schepen lange tijd in de tropen waren. Dat was het geval met de schepen van de Westindische Compagnie en de Admiraliteit (Marine) die maanden of zelfs jaren in Brazilië moesten verblijven. Uiteindelijk werd hier een oplossing voor gevonden, geen goedkope, maar het zorgde wel voor een aanzienlijke vergroting van de kans om heelhuids terug te komen.

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Een (extra) dikke houten huid
We weten al langer dat voor de schepen van de Verenigde Oostindische Compagnie (VOC) een extra opofferingslaag van dun en goedkoop naaldhout werd bevestigd op de belangrijke eikenhouten huidlaag van het schip. Deze zogeheten dubbeling werd met duizenden spijkers met grote koppen bevestigd. De roestvorming van deze spijkers en een extra laag van koeienhaar tussen de planken zorgden voor een aanzienlijke vertraging van de aantasting van de scheepshuid. Na iedere reis werd die opofferingslaag verwijderd en wanneer nodig vervangen voor een nieuwe. Deze bescherming was echter te weinig voor de schepen die lange tijd in de tropen moesten verblijven. Dit werd gecompenseerd door de toevoeging van een volledige extra huid van eikenhout. Althans dat denken we nu. In de afgelopen jaren hebben archeologen verschillende Nederlandse scheepswrakken aangetroffen met die extra dikke en driedubbele huid: twee eiken huidlagen en een naaldhouten dubbeling. Allemaal schepen die lang in de tropen moesten verblijven.

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De Utrecht
Een mooi en eerste voorbeeld uit de ‘West’ is het oorlogsschip ‘de Utrecht’ dat in 1648 zonk in de allerheiligenbaai bij Salvador de Bahia in Brazilië. Een opgraving van dit schip zou veel nieuwe informatie kunnen opleveren omdat nog vrij veel van de houten romp bewaard is gebleven. Zo zouden we erachter kunnen komen of die extra laag er al tijdens de nieuwbouw van een schip op werd gezet en dat schepen dus specifiek voor de tropen gemaakt werden, of dat die extra huidlaag er pas op een later moment werd opgezet vlak voor de uitvaart van een schip. Dit is weer interessante informatie omdat deze gegevens ons iets vertellen over planning, economie en geopolitiek.

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Nederlandse schepen dus die goed voorbereid op reis gingen. En dan lagen er nog allerlei risico’s op de loer. Een groot probleem was wel de malaria. Nog altijd is dit een ziekte – overgebracht door muggen – die je niet graag oploopt, net als het zika virus waar nu zoveel om te doen is. Dan kan het materiaal wel goed zijn, maar als de mensen zelf niets meer kunnen, dan houdt alles op.

Martijn Manders, maritiem archeoloog en hoofd Maritiem Programma RCE

Scheepswrakken voor de kust van Suriname

De Tweede Wereldoorlog wordt in het Caraïbisch gebied gekenmerkt als een oorlog waarbij voornamelijk op zee werd gevochten. De Duitsers probeerden met operatie Paukenschlag de goederen toevoer, en met name de toevoer van grondstoffen, stop te zetten. Ook vrachtschepen uit Suriname werden slachtoffer van deze operatie. Een van de schepen die slachtoffer werd van de Duitse onderzeeboten was de Frank Seamans, een meer dan honderd meter lang Noors vrachtschip die met een lading bauxiet vanuit Suriname onderweg was naar Trinidad.

In het kader van mijn thesisonderzoek heb ik samen met het personeel van de Kustwacht van Suriname, de RCE en enkele duikers verkenningstochten gemaakt om het wrak van de Frank Seamans te zoeken die voor de kust in de Atlantische Oceaan moet liggen. Helaas konden wij niet achterhalen waar het schip was, omdat de posities niet nauwkeurig genoeg waren. Er is geprobeerd met de dieptemeter van het schip alsnog een indicatie te krijgen van de locatie, maar dat leverde niet veel resultaten op. De plek, 50 km uit de kust is ongeveer 30 meter diep, maar helaas ook nog altijd zeer modderig. Er is dus geen zicht onderwater maar wel een forse stroming. Daarom hebben we uiteindelijk besloten om niet te gaan duiken. De risico’s waren te groot.

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De crew waarmee de verkenningstochten zijn gemaakt

Naast de Frank Seamans waren ons nog drie posities van scheepswrakken doorgegeven. Echter alleen de posities, dichter bij de kust en op ongeveer 10 meter diepte, waren bekend. De bemanning van het schip van de Kustwacht kon ons niet dicht in de buurt brengen, omdat niet bekend was hoe groot de wrakken waren, hoe exact de posities die bij ons bekend waren zijn en hoever deze boven de bodem uitsteken. Er waren dus grote risico’s dat het schip in aanvaring zou komen met een van de wrakken. Dit was al reeds met het ons begeleidende schip gebeurd. Daarbij was het water hier nog donkerder en onstuimiger. Netten kunnen verstrikt raken in de wrakken en  daardoor ontstaan levensgevaarlijke situaties. Ook hier dus weer een no-go wat duiken betreft. Al met al wel een teleurstelling maar we hadden dit risico ingecalculeerd. We gingen er op uit om ervaring op te doen en we hebben dit opgezet om te kijken hoe we in de toekomst projecten kunnen oppakken met onze partners.

Het is ons duidelijk geworden dat de samenwerking tussen de Anton de Kom Universiteit, het Ministerie van OWC, de Kustwacht en de Maritieme Autoriteiten Suriname (MAS) onontbeerlijk is. Ten eerste is nog maar heel weinig bekend over de wrakken voor onze kust. Sommigen hiervan zullen mogelijk een archeologische waarde hebben, maar vormen zeker ook een obstructie voor de huidige scheepvaart. Het in kaart brengen hiervan, waarbij een exacte positie, grootte en diepte van iedere obstakel wordt opgemeten is dus geen overbodige luxe. Dit zou bijvoorbeeld doormiddel van surveys met een side scan sonar al kunnen gebeuren.

Ook zou de opslag en het beschikbaar stellen van data die bij andere onderzoeken wordt verzameld (bijvoorbeeld bij onderzoeken naar olie) kunnen helpen om een beter inzicht te krijgen in de zeebodem. Direct aan dit onderzoek zou cultuurhistorisch onderzoek gekoppeld kunnen worden. Met exacte posities en side scan sonar beelden kunnen al indicaties van de aard van de vindplaatsen worden gegeven. Het combineren van onderzoek levert dus een hoop synergie en waarschijnlijk veel winst op wat betreft de inzet van geld en middelen. De komende tijd zullen de nieuwe partners in het maritiem onderzoek in Suriname de handen ineen gaan slaan om de ideeën ook echt gestalte te gaan geven.

Dharwiendre Rambharosa 

Cocos Keeling: Zoeken naar ivoor als indicator van wrakken

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Het archeologische team was zich ervan bewust dat hun 7-daagse verblijf op Cocos Keeling Islands maar weinig ruimte bood om metingen uit te voeren. North Keeling, het belangrijkste onderzoeksdoel, ligt 28 km pal ten noorden van het grootste atol en tussen de eilanden is er sprake van grote oceaandeining. Met onze boot, de slechts zes meter lange Pulu Bill van Parks Australia, stuiterden we soms over het water, zo ruig waren de golven.

Maandag was de laatste dag veldwerk op Cocos Island, althans voor het moment. We hebben de onderzoeksmetingen rond Turks Reef en Horsburgh Island afgerond. Met uitzondering van onze eerste dag op het water hebben we de afgelopen week rond Cocos Island te maken gehad met een zuidoosten wind variërend van 10 tot 15 knopen en een deining van 1 à 2 meter. Dit heeft ons aanzienlijk beperkt in onze mogelijkheden om metingen uit te voeren en te duiken op de beoogde locaties. Wat de problemen nog verergerde, was het feit dat onze doelen zich op een diepte van 6 tot 8 meter rond het atol bevinden. Dit betekent dat ze meestal net buiten de branding liggen, waardoor het bij sterke golfslag enorm lastig is om er veilig naar toe te varen en weer veilig terug te keren.

The Cocos Keeling Islands
The Cocos Keeling Islands

Zoals altijd hebben we hard gewerkt om zo veel mogelijk taken gedaan te krijgen, gegeven de lastige weersomstandigheden. Werken binnen de lagune was in elk geval wel mogelijk: op dagen dat het weer ons dwong in de lagune te blijven, hebben we op een aantal locaties metingen uitgevoerd en gedoken. We zijn nog steeds bezig met het uitwerken van de gegevens die we over de Emden hebben verzameld, maar helaas heeft de zoektocht naar de Fortuyn – ons belangrijkste doel – nogal wat te lijden gehad onder de weersomstandigheden. We hebben wel vooruitgang geboekt naar aanleiding van een melding die het Queensland Museum in de jaren ’80 heeft ontvangen over de ontdekking van een olifantenslagtand aan de zuidkant van de landingsbaan op West Island. Dit is relevant, omdat een ander VOC-scheepswrak, de Aagtekerke, naar verluidt een lading slagtanden vervoerde. Het team is het strand afgelopen en heeft rechtstreeks vanaf de kust metingen uitgevoerd met de magnetometer.

Teamlid Andrew Viduka in gesprek met de schoolkinderen op Home Island
Teamlid Andrew Viduka in gesprek met de schoolkinderen op Home Island

De volgende stappen voor het team betreffen vooral het uitwerken van de verzamelde gegevens in de komende maanden. Benieuwd wat daar uit gaat komen! De meeste teamleden bij dit veldwerk zijn afkomstig van WreckCheck Inc (http://wreckcheckinc.org), een non-profitorganisatie van Australische archeologen. Dit onderzoek was echter niet mogelijk geweest zonder de geweldige steun van onze partners, sponsors en andere organisaties en mensen die ons gesteund hebben. Onze dank gaat dan ook uit naar onze onderzoekspartner, het Maritiem Programma van het Nederlandse ministerie van Onderwijs, Cultuur en Wetenschappen (OCW), de ambassade van het Koninkrijk der Nederlanden in Australië, Silent World Foundation, Parks Australia en het Australische ministerie van Milieuzaken. We zijn enorm erkentelijk voor de uitmuntende bijdragen die Shinatria Adhityatama (ARKENAS, Indonesië) en Robert de Hoop (een Nederlandse masterstudent Maritieme Archeologie aan de universiteit van Zuid-Denemarken) hebben geleverd aan het veldwerk dit jaar. Zonder de aanzienlijke steun van het Maritieme Programma van het Nederlandse ministerie van Cultuur hadden zij niet aan het onderzoek deel kunnen nemen. Speciale dank ook aan Rob Muller, Ishmael MacRae en Trish Flores van Parks Australia voor alle geboden hulp.

 

The SMS Emden

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On Tuesday we left Christmas Island and went to the Cocos-Keeling Islands. The Cocos-Keeling Islands are a group of 27 coral islands that are located in the Indian Ocean approximately 2700 km north-west of Perth. The main islands form a typical horseshoe-shaped atoll surrounded by a coral reef. Each island has rough coral beaches to seaward and sandy beaches on the lagoon side. The islands are low lying and most are thickly covered with coconut palms. Wildlife on the islands consists mainly of seabirds. Just like on Christmas Island, land crabs are common on all islands and the surrounding reefs support a diverse range of corals, fish and other marine organisms.

Surveying again!
Surveying again!

After the team unpacked and setup base at ‘The Castle’, we started doing a magnetometer survey again. After that we snorkeled the Phaeton wreck. The Phaeton was built at Sunderland (UK) in 1868 as a composite ship (timber planking over iron frames) and was 46 meter long. It wrecked in Cocos in 1889 while carrying a cargo of copra from Cocos Island back to Europe. At about half past five on the morning of the 25 September the Phaeton was discovered to be on fire. The fire force pump was in the area of the fire and could not be reached safely and the vessel could not be saved. To avoid blocking the entrance to the lagoon, the Phaeton was run aground in its present position, broken up and salvage. We hope to make a 3D photogrammetry model of the remains of the Phaeton using photos and video we made.

North Keeling and the SMS Emden

Besides looking for the Fortuyn and the Aagtekerke one of our objectives here is to properly record the SMS Emden. This German light cruiser was at her home port of Tsing-Tau in China at the outbreak of World War 1. She was on her way on the 6th of August with orders to her captain Von Muller to destroy as much allied ships as possible. Her rampage in the Indian Ocean was brief but spectacular as she managed to sink 15 merchant ships, a Russian cruiser and a French destroyer in less than two months!


Early on the morning of November 9th the Emden appeared off the Cocos-Keeling Islands, and sent a landing party of three officers and forty-two men ashore to dismantle the cable station that was there. While they were at work the Australian cruiser HMAS Sydney arrived. Although the Emden’s gunnery was excellent and her opening salvo scored a direct hit on the Sydney, she was no real match for the larger ship. Within two hours, she was out of action, and hopelessly disabled. It was then about noon, and the Sydney left her to chase a captured merchantman which had been acting as an escort for the Emden. On her return, about 4.00 pm, she found the Emden still flying her colors, but unable to move. The Sydney signaled to her to surrender, but received no answer, and finally fired several further rounds at her. Only then did von Muller strike his flag. By this time the Emden was blazing furiously amidships, and in an attempt to save as many of his crew as possible he drove her on to the reef fringing the south coast of North keeling.

North Keeling is located approximately 27 km from the main group of islands and is thus quite remote and not a lot of people go there. It was really special to be able to dive there and see the remains of the vessel, because although it has been partly salvaged there is still a lot left of it as you can see on the photos we took. One of our team members even went on the island with Triss from Parks Australia, to document the remains of the vessel on land! Just as with the Phaeton we hope to make a nice 3D photogrammetry model of the ship to get a good overview of the site. We also documented what still remains of the vessel and did a corrosion measurement.

In the following days we will continue our survey for the Fortuyn and the Aagtekerke. We will keep you updated as good as we can with the limited internet access we have here..

 

Remote sensing process & the big blue

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Remote sensing

A crucial element in the project is the remote sensing process. The aim is to acquire, process, analyze and interpret the data and to let this follow by diving on targeted locations.

We have acquired the data with a seaborne magnetometer. This device measures distortions in the natural earth’s magnetic field through the presence of iron (or ferrous) material on or under the seabed. The magnetometer is towed on a cable behind the survey vessel, sending readings up the cable to a tablet, which logs the data and provides positioning through a GPS.

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Photo 1: The results of magnetic testing over know iron wreck site, Eidsvold, at Christmas Island. The image on the left clearly show distortions in the earth’s magnetic field, caused by the presence of the wreck. The three lines show the track of the survey vessel. The image on the right show a profile of a transect line across the sight with the clear characteristic ‘dipole’.

The tablet also helps the skipper to navigate along per-positioned lines called transects. These lines have been carefully arranged in mapping software to be straight, and parallel. Narrow line spacing is required to allow sufficient coverage.

Once the data is brought back ashore, it is reviewed on laptops with specialized software. This process allows for the earth’s magnetic field to be displayed and any distortions detected. Interpretation happens next.

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Photo 2: A magnetic anomaly discovered in the post-processing phase of the remote sensing component in the search. The anomaly is clearly seen in the paler contour lines, along with depth contour lines. This anomaly is approximately 85 by 160 meters.

A list of potential sites is produced, and the most promising analyzed more closely. Mapping software allows for the precise positioning for the deployment of divers. Circular shapes are created and placed within the mapping software, which gives a very accurate indication of depths, and can thus inform the dive plan. In this case planning for circular dive searches.

This positioning information is then fed into the tablet, enabling precise navigation to each target.

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Photo 3: Mapping and other specialized software enable the blending of magnetic isometric lines (black) and magnetic anomalies (blue and yellow), with bathymetric contour lines (white) and planned circular dive searches (red).

The entire work flow, carried out by Alex Moss and James Parkinson enables the team to react to information gathered in the field, a sort of ‘reflexive methodology’.

Penultimate day of diving on Christmas Island

Waterlogged is the best way to describe the way we all feel after the last few days. Whether diving or on the boat we have been wet. Some rain showers were so strong it was a drier feeling in the water than out of it! Sadly, our time on Christmas Island is coming to a close and we have not discovered any archaeological material that would bring us closer to the Fortuyn. While we have not yet managed to dive all the identified magnetic anomalies our time is running out. But let’s keep our fingers crossed.

DCIM100GOPROGOPR3506.Photo 4: Me descending down the shotline.

DCIM100GOPROGOPR3534.Photo 5: Alex Moss doing a 30 meter circular search. The other diver holds the line at 15 meter and makes sure the line doesn’t get caught.

Today we dived sites off the West coast and because of the very calm conditions were able to swim survey from Egeria Point northwards to Winifred Beach. The difficulty of finding a site in the 30 meter depth range available to us as divers was made very evident during that transect, as several times we encountered a vertical drop off to far greater depths not more than 50 meters from the coastline. A very small shelf for a shipwreck or shipwreck debris to stay attached to!

DCIM100GOPROPhoto 6: Graeme and Shinatria after their circular search.

DCIM100GOPROGOPR3654.

Photo 7: The MV Eisvold shipwreck is a beautiful place to dive!

Our next blog will be the last from Christmas Island, before we go to Cocos Keeling. Stay tuned!

Community involvement and diving

Lees deze blog in het Nederlands

The very generous involvement of members of the international online community has been fundamental to the progress of the Closing in on the Fortuyn project. Thomas Creemers has sent information from the Netherlands that has fundamentally broadened the list of shipwrecks and the scope of team’s activities on Christmas Island.

Until recently the list of ships known and likely to have wrecked on and around Christmas Island consisted of the Fortuyn (1724), an unnamed Dutch shipwreck (prior to 1744), the Norwegian MV Eidsvold (1942), the Japanese Nissei Maru (1942), the Indonesian asylum boats SIEV X (2001) and SIEV 221 (2010) and the Panamanian registered MV Tycoon (2012).

Thomas has sent the team a wealth of information about two more Dutch ships. They are the 1100 ton Arinus Marinus and the 496 ton Vice Admiraal Rijk wrecked respectively near and on Christmas Island in 1821 and 1852. About the latter we have already written in our previous blogs, but not of the Arinus Marinus!

The Arinus Marinus

After the 1814 Treaty of Paris, Rotterdam merchants bought British ships and used them in the Dutch fleet to the Indies. The Arinus Marinus was one of these vessels, an English frigate, built in 1803 and named the Ceylon. It was purchased in 1815 by a Rotterdam shipping company. In this capacity the Arinus Marinus was taken to the Indies in 1816 for among others the trade in tea.

Photo 1

Photo 1: The Arinus Marinus as shown on a song sheet. This song is about the wrecking of the Arinus Marinus.

In 1821 the ship was loaded in Batavia for a return trip to Rotterdam. The winds took it close to Christmas Island with fatal consequences for the 200 on board, except for four of her crew. These four people floated on a piece of wood until they were found and rescued by the crew and captain of the Danish ship the Souvereign.

The Arinus Marinus had a very special cargo on board: a natural collection intended for the Museum van Naturalien in Leiden. This collection consisted of 15 boxes. Amongst these were:

  • 5 boxes that were full of stuffed animals,
  • two boxes had prepared hides and skins,
  • 4 boxes were full of skeletons,
  • 3 boxes were filled with minerals and rock samples.
  • Also on board were 36 different plants from Java for the botanical garden in Leiden.
  • a black tiger
  • and an elephant!

Photo 2 Photo 3: Loading all the gear for diving!

Diving!

We finished the survey on Thursday so on Friday and we started diving to identify magnetic anomalies! All the planning, survey, analysis and preparation now culminates in a few dives over the coming days when we hope to see something that nature does not produce :a straight line! Nature is glorious, but humans construct materials with straight lines, be it anchor stocks, cannons, or other artefacts. The appearance of a straight line in the coral is a wonderful tell-tale that some cultural material lies below. While nature does not necessarily make straight lines underwater, when it breaks up, coral can result in the appearance of straight lines. Large plate coral literally abounds in the area we are diving. This coral can form a short straight edge when broken, periodically enough to get your heart racing before hopes are dashed.

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Photo 3: Me proceeding down the shot line.

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Photo 4: We drop a shot line at the anomalies and from there we do circular searches up to 30 meter.

We also dived on the MV Eisvold and the Nissei Maru (both WWII shipwrecks) to take corrosion measurements.

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Photo 5: Drilling and taking the corrosion measurements at the Nissei Maru.

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Photo 6: The wreck of the MV Eisvold is a beautiful spot to dive!

 On Tuesday we will leave for Cocos Keeling Islands so hopefully we will be able to dive on all the locations the magnetometer gave us some abnormal reading!