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Jaakko Nygren: The MoSSWeb-Site: New information

Minna Leino and Ulla Klemelä:The Field Research of the Maritime Museumof Finland at the Wreck Site of Vrouw Mariain 2001 - 2002

Minna Leino:Introduction of the Wreck of Vrouw Maria

Ismo Malinen: Research in the history of theSnow Vrouw Maria

Jaana Mellanen: Clay tobaccopipes from the Vrouw Maria

Paola Palma:What’s on? The MonitoringTheme

NewsletterMonitoring, Safeguarding and Visualizing North-European Shipwreck Sites: Common European Cultural Heritage - Challenges for Cultural Resource Management

A shipwreck research project funded by the European Union Culture 2000 Programme

1/2003

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Theme:

Newsletter 2002:ITheme: IntroductionDecember 2002

Newsletter 2003:ITheme: Vrouw MariaMay 2003

Newsletter 2003:IITheme: The Darsser KoggeMay 2003

Newsletter 2003:IIITheme: The Eric NordevallJune 2003

Newsletter 2003:IVTheme: The Burgzand Noord 10September 2003

Newsletter 2004:ITheme: The Visualization ThemeMarch 2004

Newsletter 2004:IITheme: The Monitoring ThemeJanuary 2004

Newsletter 2004:IIITheme: The Safeguarding ThemeMay 2004

Newsletter 2004:IVTheme: The presentation of theresults of the projectJune 2004

Vrouw Maria

MoSS Newsletter 2003 / 1Theme: Vrouw MariaNewsletter Timetable and Contents

May 2003

Sallamaria Tikkanen:What is MoSS ?

What’s on? Meetings and Seminars

22The First MoSS Seminar in Schwerin,Germany. What happened? 23

Stefan Wessman:The Documentation and Reconstruction ofthe Wreck of Vrouw Maria

Minna Leino: Experiences of the UnderwaterPositioning System AQUA-METRE D100

Martijn Manders: What’s on? The BZN-10Site

Carl Olof Cederlund: What’s on? The E.Nordevall project and it’s developments2001-2002

Hauke Jöns: What’s on? The Darsser KoggeSite

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MoSS is a three year shipwreckresearch project funded by theEuropean Community Culture2000 Programme. The projectopens an underwater window tofour significant Europeanshipwreck sites in theNetherlands, Germany, Swedenand Finland. The project isorganized by six Europeancountries in 2001-2004. Theproject deals with the monitoring,safeguarding, and visualizing ofshipwrecks. The project aims attelling European citizens aboutunderwater cultural heritage andthe importance of its protection.

he MoSS project isbased on fourshipwrecks, all ofwhich are of greatsignificance from aEuropean point of viewand show a diversity of

intercultural relationships throughouta long period of history. The wrecksare located in Netherlands, Germany,Sweden, and Finland, and theyrepresent different vessel types. Theoldest of the wrecks is dated to the13th century whereas the youngestis from the middle of the 19th century.The wrecks are in different kinds ofunderwater environments; in sea,lake, and brackish waters, and theconditions on the sites are bothstable and unstable. The wrecks havepreserved extremely well; two of themare almost intact.

“The project opens anunderwater window to

four significant Europeanshipwreck sites in theNetherlands, Germany,Sweden and Finland.”

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The MoSS project has three mainthemes: monitoring, safeguardingand visualizing shipwrecks. The firsttheme includes monitoring thecondition of the wrecks, or in otherwords doing research on thedegradation of shipwrecks underwater.

The aim of this theme is to developand improve the methods used inmonitoring the physical andenvironmental conditions ofshipwrecks. The second theme issafeguarding, which aims at outliningand developing models to protectshipwrecks so that also the needs ofdifferent public groups are taken intoaccount. The third theme isvisualizing. The four shipwreck siteswill be made physically visible usingunderwater and other images. Theproject will be advertisedmultilingually to the European public.

“The MoSS project hasthree main themes:

monitoring, safeguardingand visualizingshipwrecks”

The MoSS project will consist alsoof fieldwork, Internet site,publications, posters, leaflets,reports, articles, meetings, andseminars. One of the objectives is toproduce information not only to thegeneral public but also to the expertsin the area of protecting the culturalheritage. The aim is to awakenEuropean peoples’ interest to ourcommon underwater cultural heritageand to have the general publicparticipate in protecting the heritage.The wrecks of the project - ships thatsailed on European waters - act asexamples of maritime history as theytell us about the many local andinternational dimensions of theEuropean culture.

The MoSS project is organized by TheMaritime Museum of Finland (co-ordinator), The Mary RoseArchaeological Services Ltd. (UnitedKingdom), The National Service forArchaeological Heritage: NetherlandsInstitute for Ship- and UnderwaterArchaeology ROB/NISA (theNetherlands), The National Museumof Denmark/Centre for MaritimeArchaeology (Denmark), TheDepartment for Preservation ofArchaeological Sites and Monuments/ Archaeological State Museum ofM e c k l e n b u r g - Vo r p o m m e r n(Germany), and Södertörns högskola– University College (Sweden).

The MoSS Project is the firstinternational shipwreck project thatEuropean Community Culture 2000Programme funds. The EuropeanCommunity Culture 2000 Programmeis a programme that supportsinternational cultural co-operationprojects that involve organizers fromseveral countries. The objectives areamong other things to encourage co-operation, to promote the commonEuropean cultural heritage, and todisseminate the knowledge of thehistory and culture of the peoples ofEurope. In 2001, it was the first timeprojects on sub-aquatic archaeologywere especially called to take part inthe program.

For more information, pleasecontact Ms Sallamaria Tikkanen,MoSS Project Leader, The MaritimeMuseum of Finland,tel. +358 9 4050 9057,fax +358 9 4050 9060,sallamaria.tikkanen@nba.fi

Web site:http://www.mossproject.com

What is MoSS?

Sallamaria Tikkanen, The Maritime Museum of Finland

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A monitoring strategy has beenapplied from the end of May 2002 tothe three MoSS wreck sitesmeasuring the environmentalvariables that affect wood onunderwater archaeological sites.

Very often these variables areidentified as threats to thepreservation and the survival of a site.Therefore the monitoring procedureaims to identify and analyse thepotential dangers in order to studyand provide the right methodology forconducting and possibly piloting thedevelopment of monitoring protocols.

In the spring of 2003, the MoSS WebSite will be updated with new layoutand fresh information. The site is nowin three languages - Germany,English and Finnish – but therenewed site will also be in Dutch andSwedish.

The new MoSS Web Site usesMacromedia Flash 6 and Shockwave3D Internet technology. It will be anaccessible and rich site with videomaterial, 3D virtual wrecks andanimations. It is already possible togo on a virtual tour at the Vrouw Maria3D reconstruction, where for examplethe hull of the ship can be seen theway it once was.

Both Macromedia Flash andShockwave can be downloaded in theInternet.

You are welcome to visit the newMoSS Web Site atwww.mossproject.com

It is fundamental to assess theenvironmental dynamics as well asanalyse the sediments thatencapsulate archaeological material.

The investigation of the site formationprocesses will be focused onchemical, physical and biologicalfactors. The biological aspects to beresearched are the presence ofbacteria and marine fungi activities aswell as that of wood boring animalsand human activities. The chemicalaspects to be investigated are waterquality and the chemistry of thesediment. The physical aspect willfocus on sediment and watermovements and erosion of timbers orartefacts.

The MoSS Web Site: New Information

MonitoringPaola Palma,

Jaakko Nygrén, The Maritime Museum of Finland

What’s on?The Mary Rose Archaeological Services Ltd.

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Minna Leino, The Maritime Museum of Finland

Introduction ofthe Wreck of Vrouw Maria

n Finland’s territorial waters,there are more than thousandwrecks from different eras.One of these is of specialinterest: it is a wreck of a shipof the type snow in thearchipelago in the most

southwestern parts of the country. Atthe depth of over 40 meters, the wreckappears well preserved. By the helpof historical documents and maritimearchaeological research, we nowknow the wreck is that of a DutchSailing ship called Vrouw Maria.

Vrouw Maria was a two-mastedmerchant vessel on her way fromAmsterdam to St. Petersburg in theautumn of the year 1771. On a stormynight in the outer archipelago ofNauvo, Vrouw Maria sufferedshipwreck and, a few days later,sank. According to the entries of theSound customs house in Denmark,she was with a cargo of sugar,dyestuff, zinc, cloths, and unspecifiedsingle items. Vrouw Maria has areputation of a treasure ship becauseher cargo consisted of art treasuresbought by Russian aristocrats andCatherine the Great. Among theworks of art there were for exampleDutch paintings from the 17th century.A part of the cargo was salvaged soonafter the shipwreck, but the majorityof it went down with the ship.

History of Research

The very first documents about thehistory of Vrouw Maria were found byDr. Christian Ahlström in the FinnishNational Archives as early as in the1970’s. The most important sourcefor researchers is the ship’s protest,which was found in the municipalarchives of Turku. The documentconsists of an extract of VrouwMaria’s logbook and a list of the thingsthat were salvaged. In the DiplomaticaCollection in Riksarkivet, the SwedishNational Archives in Stockholm, thereis diplomatic correspondenceconcerning the attempts to searchand salvage the ship.

For years, amateur divers tried to findthe wreck. In 1999 Mr RaunoKoivusaari and other members of asociety called Pro Vrouw Mariamanaged to locate the wreck using aside-scan sonar. The FinnishMaritime Museum, being responsiblefor the underwater cultural heritage inFinland, started field research on thewreck site in the summer of 2000.Since 2001 Vrouw Maria has been apart of a European project calledMoSS (Monitoring, Safeguarding andVisualizing North-EuropeanShipwreck Sites), the firstinternational shipwreck project withinthe European Community Culture2000 Programme.

The Wreck

The wreck appears at sailing positionin a small deep that is surrounded byshallows. The wreck is approximately26 meters long and 7 meters wide. Itlies on its keel on the bottom of thesea and leans on its starboard side.The masts, which are standing up,rise to a depth of 22 - 24 meters. Themasts are made of three parts, andthe upper parts have fallen down onthe starboard side of the wreck onthe bottom of the sea.

In general, the framework of the shipseems to be in good condition. Thesalvage operations at the time of theshipwreck did, however, damage theship: the rudder is lacking, and thetransom is lost as well. The ship’sfive-meter-long tiller lies partlycrosswise on the stern deck on thestarboard side. On the deck, thereare various single parts of theframework that either came off whenthe ship sank or that have fallen downfrom the rigging in the course of time.Among these pieces are the remainsof the deck cabin. The windlass isundamaged, and there is still a leverattached to the windlass stock. Boththe pumps are still upright, and oneof them still has the piston rod in itsplace.

IFig. 1. A side scan sonar image ofthe wreck of Vrouw Maria. Image: TheFinnish Defense Forces.

Fig. 2. The reference point No. 1 on top of a bollard. Photo: Jouni Polkko.

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n the years of 2001 and 2002,the Maritime Museum ofFinland used all in all sevenweeks on the field researchat the wreck of Vrouw Maria.Besides the researchers ofthe Museum, at the site there

were also voluntary divers. The diversused both compressed air and trimixas breathing gas. The researchersand the divers used the oldcoastguard station of Bodö as theirbase on land and an old trawler calledm/s Teredo was the group’s supportvessel. The working days were ratherlong since the mere ride from Bodöto the wreck site takes an hour and ahalf.

When the fieldwork was first started,the divers went underwater from amoving small boat. To ease the diving,a fixed anchoring system was put upon the support vessel in the summerof 2001. The Finnish MaritimeAdministration placed heavy weightsnear the wreck and now buoys arefastened to the bottom of the sea.

Surroundings and Monitoring

The Finnish Maritime Administrationand the Geological Survey of Finlandwere appointed to investigate thesurroundings of the wreck in thesummer of 2001. The FinnishMaritime Administration examined theprofile of the sea bottom near thewreck with a multi-beam sonar. Thegeological analysis made by theGeological Survey of Finland showedthat Vrouw Maria lies on a thick layerof clay. Only the thin top layer is ofsand/moraine.

The monitoring of the wreck wasstarted in 2001 in co-operation withthe Finnish Institute of MarineResearch. The environmentalinvestigations and the monitoring ofthe wreck help not only in the researchof the condition of the wreck but alsoin the planning of the conservationand the possible salvage of the wreck.At the beginning of June, an ADCP(Acoustic Doppler Current Profiler)apparatus that measures watermovements and two otherapparatuses that measuretemperature were placed at the site.Information about the watermovements in the summer wasunfortunately of no use but the dataconcerning the water temperature inJune-November show that the watertemperature near the wreck, in thedepth of 41 meters, can changenotably. At its lowest the temperaturewas not more than – 0.7°C.

Safeguarding

The wreck is located in the outerarchipelago, by the open sea, whereit is exposed to winds. There are noshipping channels or humansettlement near the wreck. TheCoast Guard of Finlandhas the area under constant camerasurveillance, and there has not beenany kind of unauthorized activity atthe site. Lowering the anchor anddiving are in fact forbidden at the sitesince 2000.

The research work itself is a dangerto the wreck. When anchoring thesupport vessel near the wreck, thereis a notable risk that the remains ofthe almost intact hull are damaged.

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The Field Researchof the Maritime Museum of Finland at the Wreck Site of Vrouw Maria in

2001 – 2002

Minna Leino and Ulla Klemelä,The Maritime Museum of Finland

Fig. 3. Above the windlass can be seen the bowsprit, which today is leaningagainst the bow next to the stempost. Photo: Jouni Polkko.

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In the autumn of 2002, a CTD(Conductivity Temperature Depth)apparatus was placed near the stemof the wreck in order to investigatethe water temperature, conductibility,salinity, oxygen, pH, turbidity and theredox potential. At the same time, theADCP apparatus started measuringthe current profile in the entire watercolumn. The first set of data wascollected in December 2002.According to preliminary results, theconditions near the sea bottom wererather stable from the beginning ofSeptember to the end of October.Only the oxygen level had dropped,which means that the stratificationwas so strong that the water at thebottom had yet not blended with theoxygenic water of the surface. On the23rd of October, the qualities of thewater at the bottom suddenlychanged: the temperature and thelevel of oxygen rose, the salinity ofthe water dropped, and the watermovements from the bottom up to thesurface were very dynamic. Thereason for the blending and movingwas a strong wind that blew from theeast that day.

The deterioration of wood isinvestigated by the help of woodensamples. In June 2002, five metalgrids with 33 samples each wereplaced at the site. The samples helpus to determine the types of woodboring animals, fungus and bacteriathat decompose waterlogged wood.In addition, the aim is to find out howwell the wood wears and what are thechemical changes that take place init. A part of the samples are wrappedwithin filter-textile of different grades.The aim is to get information aboutthe way the textile protects woodenwrecks from mechanical wear anddifferent wood boring organisms thatgnaw wood. The first set of sampleswas raised from the site and sent tothe Mary Rose Archaeological

Services to be analysed, but theresults are not yet ready.

Also the biological, chemical andphysical changes in wood within thesea bottom are analysed by the helpof wooden and textile samples. In theautumn of 2002, an ejector pump wasused to insert three plastic tubes withsamples to be embedded in the seabottom near the stern of the wreck.The pump was not, however, very wellsuited for this purpose and theresearchers did not manage to getthe samples in an entirely anaerobicenvironment. The results from this setof samples can therefore not becompared with the results from theother two wrecks within themonitoring theme of the MoSSProject. The rest of the samples willbe placed at the site in the summerof 2003, and it is our intention toembed them in the sea bottom so thatthe circumstances surely areanaerobic and that the results are of

real use in the view of the project’smonitoring theme.

Underwater Investigations

The extent of the site was measuredby a side-scan sonar, divers, and aROV operator. One of the ship’sanchors was found deep within thesea bottom next to the wreck, whichmeans that Vrouw Maria sankprecisely where the shipwreck tookplace in 1771. When diving, the mainemphasis of the research was put onbasic documentation work with non-destructive methods. One of the aimswas to receive information for acomputer-aided three-dimensionalreconstruction of the wreck. Theinformation was gathered bymeasuring the hull and pieces of thewreck from the outside. It is difficultto estimate the strength of thewreck’s structure since all thesignificant joints are under the cargoinside the wreck.

Fig. 4. Woodsamples are being prepared at the pier of Bodö. Photo: UllaKlemelä.

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In the documentation work, theresearchers did a lot of photographingand videotaping. Most of the differentlengths were determined with tapemeasurement but also an Aqua-MetreD100 apparatus was used. Thedifferent angles were successfullygauged with a digital inclinometer andthe shapes of the hull were easilydetected. A mini robot camera (ROV)investigated the interior of the wreck.The interior investigating takes timebecause there is free space betweenthe cargo and the deck beams onlyfor half a meter. The wainscots, whichcan be seen through the sediment,are broken at their upper ends. Whatmakes the research work even moredifficult is the even layer of sedimentthat covers the cargo everywhere. Thisis why it has not been possible tofind out the use of the inner parts ofthe ship.

“In the hold there arepacking cases, half-broken

barrels, a box filled withlenses, zinc ingots...”

The researchers have, however,managed to locate the crew’squarters in the bow, the hold, and acabin in the stern. In front of thewindlass there is a brick stovepipethat reveals the location of the ship’sgalley. The pipe reaches the deck.The use of a deck cabin behind themainmast remains unclear since thetop part of the mast has collapsedand damaged the cabin badly. In thehold there are packing cases, half-broken barrels, a box filled withlenses, zinc ingots, clay tobaccopipes, lead seals, and something thatmay well be rolls of cloths. We donot yet know all the art treasures inthe cargo but we believe that thereare at least eleven Flemish, Italian,and Dutch paintings from the 16th and17th century.

Visualisation

The material collected during thebasic documentation work was usedwhen the wreck was visualized to thegeneral public by the making ofdrawings. At the site there were alsoprofessional photographers andfilming groups. In the summer of 2001there was a Canadian productioncompany Echo Nova Productionsmaking a film called Catherine theGreats Ghost Ship. The film is a partof the National Geographic TV SeriesSea Hunters and it tells about thehistory of Vrouw Maria. In the summerof 2002 there was a Finnishproduction company Matila & RöhrProductions at the site. The companyhad stationary lighting system withthem so that the whole deck wasalmost completely lit up. In additionto this, we did some experimentalphotographing with a tripod andnatural light.

We now have two models of thewreck; one is a traditional scale modeland the other is a computer-aidedthree-dimensional reconstruction ofthe wreck. The scale model is onexhibition at the Maritime Museumof Finland. The builder of the modelis Kalle Salonen who knows thewreck of Vrouw Maria extremely well.He has dived on the wreck dozens oftimes and worked as a ROV operatorduring our field research. Salonen hasalso used hundreds of hours inwatching videotapes on the wreck.

In the view of the visualisation theme,the computer-aided three-dimensionalreconstruction of the wreck is veryuseful since our intention is to have iton the Internet site of Vrouw Maria.

Future Investigations

Even if time seems to have stoppedat the sea bottom, the degradation ofthe wreck will not come to a stop.During the three-year researchproject, the aim is to carefullyexamine the circumstances at thesite in order to be able to foresee thechanges that will take place in thenear future. We cannot guaranteethat the wreck will be preserved. Thefield research will go on in thesummer and autumn of 2003.

When the field season 2003 ends, webelieve that most of the basicdocumentation work on Vrouw Mariais done. The collected information willthen help us to make the rightdecisions when it comes to the futureof Vrouw Maria. Should we salvagethe wreck and have it on show in amuseum? Should all or some of theexcavation be done in the depth of40 meters, or would it be better if thewreck were moved in shallowerwaters before the excavation? Orshould we leave the wreck untouchedfor the future generations?

Fig. 5. A cathead at the bow of thewreck. Photo: Jukka Nurminen.

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he Maritime Museumof Finland began fieldresearch on the wreckof Vrouw Maria in thesummer of 2000.Researchers, who

were aided by a group of voluntarydivers, documented the wreck byphotographing and videotaping it fortwo weeks. At the depth of over 40metres, the wreck appears at sailingposition with its hull intact. The depthand the state of preservation makethe wreck a challenging target fordocumentation. To speed up thedocumentation process, theresearchers needed moderntechnology, and they wanted to testan underwater positioning systemalready in the summer of 2001.

Acoustic positioning systems have areputation amongst marinearchaeologists for being expensive,complex and hard to get hold of. Thefact is, however, that there aredifferent sorts of underwaterpositioning systems that have beendeveloped especially for underwaterarchaeology (e.g. SHARPS, HPASSetc.). At the Maritime Museum ofFinland, we had no previousexperience of equipment of this kind,and we decided to get familiar withone of these systems. We werelooking for equipment that wasinexpensive, easy to deal with andeffective enough to be fit for use atthe wreck of Vrouw Maria. Thenearest offer of rent came from Francefrom a company called P.L.S.M.(Positioning Locale Sur la Mer).

P.L.S.M. is specialised in accurateunderwater acoustic positioningsystems. The company started in1996/97 with the development of anew local underwater positioningsystem for underwater archaeology.The marketed version of this systemis called Aqua-Metre D100.

System Definition and Experiencesof the Main Units

The Aqua-Metre D100 is a localunderwater positioning system basedon an acoustic interferometricscheme (mainly known as Ultra ShortBase Line or USBL). It is particularlysuited to accurate local 3D locatingwithin the range of up to 100 metresfrom the reference point. It is a stand-alone system; there are no cablesfrom the base to the surface, and asingle diver can operate it.Measurement set up and retrieval areperformed using standard PC basedsoftware and an infrared data link. TheDXF file format output allows directlink to CAD tools.

The Aqua-Metre D100 is made of twomain components: the base and thepointer (fig. 1). The measurementbase constitutes the referenceCartesian coordinate system {0,0,0})at the top of a mast, which is twoand a half metres. The mast remainsunderwater during the wholemeasurement operation. The basehas to be charged on the surfaceapproximately once a day.

The system requires at least tworeference points. The samecoordinates can be used during thedocumentation even if the base ismoved. The computer takes care ofall of the coordinates in the dataretrieval phase. The portable pointer,which includes a small keyboard andLCD display panel, allows the diverto measure positions (x, y and zcoordinates) and save them in theback-up memory. The pointer is fittedwith a rod that creates measurementoffset from the sea bottom.

In principal the main components arepretty straightforward to use. Theinformation is easy to pick up in themanual, which is available in Frenchand also in English. In practice thereare a few pitfalls. In our opinion, thereought to be a checklist the diver couldfollow at the beginning of themeasuring. Once the pointer is at themeasurement mode, it is easy tocontinue. The shields in the base andin the pointer ought to be easier touse. They are too delicate to beoperated with cold-water-diving-gear(especially with gloves).

AQUA-METRE D100Underwater Positioning System

Figure 1. Aqua-Metre D100.

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Minna Leino, The Maritime Museum of Finland

Experiences of the

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The rod of the pointer is 1,32 m longand in case you cannot attachyourself to anything, you really needto be a master in buoyancy becausethe pointer allows an inclination of 5degrees only. The pointy end of therod is made of plastic, which makesit very slippery - why not make it ofrubber, for example? Normally thepointy end of the rod is the only thingtouching the object that is beingmeasured and therefore the touch ofthe rod should be as soft as possible.The LCD panel of the pointer is in avertical position during the measuringoperation, which makes it difficult forthe diver to read and press thebuttons.

Suitable Underwater Environmentfor the Use of Aqua-Metre D100

To be able to operate, the Aqua-MetreD100 requires a direct acoustic pathbetween the base and the pointer.Below the direct acoustic path, theremust be clear water at least for onemetre so that reflections from thesurface can be avoided (fig. 2). Anobstacle between the base and thepointer affects the accuracy of themeasurements or simply makes theacoustic wave vanish. For example,a diving partner can affect themeasurements if he or she happensto swim across the path.

The system requires a depth of atleast 5 metres to be able to operatewell because the base itself takes 2,5metres and then there has to be waterfor at least another 2,5 metresbetween the interferometric frame ofthe base and the surface (fig. 2). Ifthere is not enough water above thebase, the acoustic reflections from thesurface make a direct acoustic pathimpossible. When working on areaswhere the depth is not more than 5metres, the distance between thebase and the pointer cannot be more

than 30 metres. Otherwise theaccuracy may be reduced becauseof the severe multipath environment.According to the manufacturer, themaximum distance between the baseand the pointer is 100 metres, and tooperate well in this area, the systemrequires a depth of at least 10 or 15metres. When planning the locationof the mast in the investigation area,one must remember the blind areaaround the base (fig. 4). When themast is in a slope the blind area iseven larger.

If the documented area is surroundedby steep bedrock outbursts these willaffect the measuring process. Onareas too close to the outbursts, theuse of Aqua-Metre D100 isimpossible. We know now from ourexperience that one must not bewithin 2 - 4 metres from outbursts.(The distance depends on thesteepness of the cliff.) One shouldpay attention to researching thetopography of the investigation areabeforehand!

Testing at the Vrouw Maria WreckSite in 2001

There must be a direct acoustic pathfrom the base to the reference pointsand therefore it is sensible to haveseveral reference points to begin withto guarantee that the direct acousticpath is as wide as needed. A greatdeal of thought was put into planninghow the reference points and themast of the base had to be situatedon the site of the Vrouw Maria. Ourtask was to map the deck level of thewreck and the loose parts on the seabottom around the wreck.

Eight reference points werehammered into the wreck with coppernails. The points were situated on topof bollards and in the railing in differentparts of the wreck. We chose copper

nails because copper is not corrosiveand in this way the wreck suffers onlyfrom the holes made by the nails. Wedecided to install two masts for thebase on the deck of the wreck to avoidgetting the upstanding masts in theway of our measurements. Betweenthe hatches the deck was in such agood condition that it was possibleto place the masts there. Normallyone should prefer the sea bottom andnot rely on the construction of thewreck.

We used both compressed air andtrimix as breathing gas. The bottomtime with trimix is half an hour, andwith compressed air the time is notmore than half of this. The systemset up takes about five minutes divingtime. The set up includes the fittingof the base into the mast, taking offthe shield and switching on the power.The base starts a self-calibrationprocedure after this. In other words,when all this is done, one third of thebottom time of divers breathingcompressed air has already passed.Therefore it was natural to havetrimix-divers to do the firstmeasurements with Aqua-MetreD100.

Divers managed to measure sevenout of the eight reference points, andit was really hard work to keep stillfor several minutes. Four of the pointstook two minutes per point tomeasure, and the time spent for therest of the points was from five toseven minutes. The system was notfunctioning as easily as in shallowerwaters. We began to believe that theNiMh batteries were the reason forthe malfunctioning and contacted theinventor Mr. Medard. He came toFinland with a new type of batteries(NiCd). Meanwhile, we did several testdives but without success (Table 1).The seven successful measurementswere then compared with

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measurements that had been takenwith tape measurement. Thedispersion varied from 3-11centimetres.

Mr. Medard suspected that therecould be acoustic noise from thebackground interfering with themeasurements but after havingmeasured the silence of thedeepness of the Baltic he had toreject this idea. However, it was animportant point he made and oneshould always make sure that forexample the echo sounders from thesupport vessels and other possiblesources of acoustic noise are turnedoff. We managed to dive successfullywith the new batteries once - althoughthe diver had forgotten to take off theshield on top of the pointer.Unfortunately, after this dive thepointer started to warm up becauseof a leak. The leak was confirmed inthe laboratory of the P.L.S.M. and atthe same time also a fracture in apower wire was found. The P.L.S.M.suspected that our problems werecaused by this fracture. This was afalse conclusion, and it had an effecton our research in the following field-season!

Hard Testing Leads Us to Results

In the autumn of the year 2001 wehired the equipment again to test itin different underwater environments.We used Aqua-Metre D100 at thewreck of Kronprins Gustav Adolf andat two different wreck sites near thefortress island of Suomenlinna in frontof Helsinki.

At the first wreck at Suomenlinnathere were steep bedrock outbursts,which restricted our area, butwhenever there was a connection theequipment was working fine. At thesame wreck site we tested also themarking of the points. The markinglabels were pressed into the wood withthe aid of a copper thumb-pin. It didnot attach well enough and morethoughts were given to improve theROV co-operation in order to have anon-line connection. A good ROV co-operation would make the markingof the exact points unnecessary.

The third testing took place at a smallwreck that is dated to late 17thcentury. The wreck is almostcompletely covered with mud and onlyparts of the frames were visible. Thewreck, lying at the depth of sevenmetres, was mapped with a TotalStation operated from the ice abovethe wreck. The points weremeasured also with the Aqua-MetreD100, and the accuracy seemed tobe good. We were pleased with thetest results. The equipment was sentback to France to wait for our nextfield season.

In May 2002 the Aqua-Metre D100was back in Finland again and newstaff of the Maritime Museum of Fin-land was rehearsing the use of thesystem on the nearby waters of themuseum island. One day an old minepond, Ojamo, acted as a test placefor the voluntary divers of the VrouwMaria Project. The equipmentfunctioned properly and we preparedourselves for the research camp witha peaceful mind.

Figure 3. System accuracy.

Figure 2. Direct Acoustic Path.

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At the research camp, the difficultiesstarted again. Bad experiences fromthe previous summer had made theresearch group a little suspiciousabout the equipment. Changes hadbeen made in the parameters so thatthe address of the pointer was wrong,which led us to believe that all of asudden the equipment was notworking at all. The error was spottedafter a while and the measuring at theVrouw Maria wreck site could start.The equipment was tested duringthree different dives and every timethere was a signal from the base,which indicated problems with thepower system. Because the contactbetween the base and the pointerwas very weak, we decided to giveup testing and consult Mr. Medard inFrance.

After the field operations at the VrouwMaria wreck site, the investigationteam of the Maritime Museum ofFinland moved to continue theresearch at a site nearby - a medievalship wreckage scene at a placecalled Egelskär in the parish ofNauvo. The task was to document thetop layer of the scene and to lift upforeseeable ceramic pots and otherobjects. The wreckage scene is on aslope and the base was locateddownhill. Reference points werecreated. At first we had difficulties inmaking the equipment work, but thereason for our problems turned out tobe a diver's diving gear that had a verynoisy Jetstream first stage. All in all32 objects were taken off the site andthe majority of the locations weredetermined by the help of the Aqua-Metre D100. The equipment did notwork within a two-metre radius of thebedrock outburst. Otherwise theequipment was working just fine sincethe temperature of the surroundingwater was +10 C. For the diver, themost difficult part of the dive was totry not to kick the 700-year old pots

with his fins when keeping the pointerstraight.

Conclusions

It is easy to agree with the commonview that the acoustic positioningsystems are expensive, complex andhard to get hold of. Nevertheless,after two years of testing the Aqua-Metre D100, we still have faith in themodern technology and its aid indocumentation. The timetable has,however, become more realistic: thedevelopment of the systems will takesome time. I believe that it is ourmoral duty to take part in thisdevelopment process as thoroughlyas we can. Our testing may helpthose who develop the systems andI would like to think that this way themany perspectives of our delicateresearch subjects becomeappreciated by technical experts aswell.

The inventor of the Aqua-Metre D100did finally test the NiMh batteries incold water in the autumn of 2002. Thetest indicates clearly that the powerdiminishes when the watertemperature drops under +5 C. At theVrouw Maria wreck site the watertemperature was +3,5 C at the timeof our investigations. The power fromthe batteries was clearly insufficient.In the summer of 2003, we will once

more try to make the Aqua-MetreD100 work at the wreck site of VrouwMaria. If it still does not work, evenwith different batteries, that is, we willhave to make the conclusion that thesystem operates only when the watertemperature is over +5 C.

References

Green, Jeremy, Duncan, Alec 1999:Report on the 1998 evaluating trialsof the High Precision AcousticSurveying System (HPASS). TheInternational Journal of NauticalArchaeology vol 28 no 1, 1999.

Greenough, J., Dart, P., Holt, P.:Recent Developments in AcousticTechniques used in MarineArchaeology. Web-publication (http:// w w w. t h r e e h . d e m o n . c o . u k /Downloads/Recent Developments inAcoustic.pdf)

Green, Jeremy, Duncan, Alec 1999:Surveying shipwrecks and trackingROVs with the High PrecisionAcoustic Surveying System(HPASS). Web-publication (http://www.threeh.demon.co.uk/Downloads/ShallowWaterConference99.pdf)

Medard, Joel 2001: Aqua-Metre D100User Manual.

Figure 4. The Blind Area.

MMMMMOSS

12

Divers

Minna LeinoMatias Laitinen

Pasi RaasakkaLeo Teräväinen

Pasi RaasakkaLeo Teräväinen

Minna LeinoMatias Laitinen

Niko NappuKai Jahnsson

Pasi RaasakkaLeo Teräväinen

Pasi RaasakkaLeo Teräväinen

Niko NappuKai Jahnsson

Minna LeinoMaija Flinkman

Topi SellmanPekka Paanasalo

Pasi RaasakkaKalle SalonenPetri PuromiesTimo Niemi Juha Flinkman

Tetti Sinisalo Peik Joutsen

Timo NiemiJuha Flinkman

Topi SellmanPekka Paanasalo

Minna LeinoPasi Raasakka

Minna LeinoPasi Raasakka

xxxxxx

Mikko KiirikkiJaakko Nurmela

Date

17th of June 2001

18th of June 2001

20th of June 2001

20th of June 2001

20th of June 2001

20th of June 2001

21st of June 2001

21st of June 2001

21st of June 2001

25th of June 2001

25th of June 2001

25th of June 2001

25th of June 2001

26th of June 2001

26th of June 2001

27th of June 2001

28th of June 2001

29th of June 2001

2nd of July 2001

Mission

To find suitable places for the masts.

To install the first mast.

To install the second mast.

To check the direct acoustic pathsbetween the reference points and themasts with tape measurements.

To check the direct acoustic pathsbetween the reference points and themasts with tape measurements.

To check the direct acoustic pathsbetween the reference points and themasts with tape measurements.

To install reference points 1 - 4.

To install reference points 5 - 8.

To check the reference points.

To reinstall the reference points.

To install the interface into the mast.

To install the base and start themeasuring of the reference points.

To move the base into the SB mastand measure the reference points.

To continue measuring and testdifferent threshold levels.

To test the equipment.

To test the equipment.

To test the equipment.

To change the batteries.

To install the base into the mast andcontinue the measuring of thereference points.

Table 1. Table over the measures taken for installment of the Aqua-metre D100 underwater positioning system at theVrouw Maria site.

Success

Between the hatches there was a suitable area onwhich there were no vulnerable objects.

The mast was taken to the right place and straightenedinto upright postion.

The mast was taken to the right place and straightenedinto upright postion.

Direct acoustic paths were possible between both ofthe masts and four different reference points.

Direct acoustic paths were possible between both ofthe masts and two different reference points.

Direct acoustic paths were possible between both ofthe masts and two different reference points.

Reference points (copper nails and code signs) werehammered into the right positions.

Reference points (copper nails and code signs) werehammered into the right positions.

Some of the nails were moving so they needed to behammered more.

Reference points (copper nails and code signs) areready to be used.

One of the two interfaces was installed.

Seven out of the eight reference points weremeasured, problems with the batteries.

The pointer gave error signs only. Tried to increase thethreshold.

-45 db,-35 db, -30 db, and -20 db were tested withoutany influence. It took 10 minutes to measure one point.

At the reference point no 1 the pointer collectedinformation until 3/94. The base was giving red signal.

The test was unsuccessful (the shield on the basewas not removed).

The pointer gave error signs only.

Mr. Joel Medard replaced the NiMh -batteries of thepointer by NiCd -batteries.

All of the reference points were measuredsuccessfully.The diver forgot to remove the shiled onthe pointer. The pointer had a leak and was completelydistroyed.

Preliminary Program

To be held on Friday-Saturday, the 27 th and 28 th ofJune 2003 in Sweden at the Vasa Museum, Stock-holm and at Forsvik Industrial Heritage and ShipyardAssociation, Karlsborg.

The Seminar is open for the general public

Invitationto the Second MoSS Seminar:

A Seminar on the Visualization of Shipwrecks and Shipwreck Sites.

For more information, Please visitwww.mossproject.com

Friday, 27 June 2003

General public day:

Session I. The visualization of the Vasa and theVasa museum:

Chairman: Director-General Keith Wijkander.

13.00 – 13.15 Welcome words. By Director-General of the Swedish National Maritime Museums,Dr. Keith Wijkander

13.15 – 16.00 Tour at Vasa Museum, followedby three presentations:

1. How it is working? By Klas Helmerson,Museum Director of The Vasa Museum

2. The conservation of the Vasa – today andin the future. By Ingrid Hall-Roth, Head ofpreservation of the Swedish National MaritimeMuseums

3. National and international aspects on theuse and preservation of the maritime culturalheritage. By Björn Varenius, Head of the dept ofCultural History of the Swedish National MaritimeMuseums

The general public in the Vasa Museum will bewelcome to follow the lecture program. (The seminarand the lectures in it will be announced in themuseum’s newsletter for the summer.)

16.30 – 20.30 Trip by bus to Forsvik (4 hours)

21.30 – 22.30 A light supper in Forsvik

Saturday, 28 June 2003

General public day:

Session II. Introduction session / The ForsvikIndustrial Heritage and Forsvik Shipyard

Association:

Chairman: Director-General Birger Bäckström

08.30 – 08.45 Welcome words. By Director-General Birger Bäckström, Chairman of the Boardof the Forsvik Shipyard Association, and LarsBergström, Director of The Forsvik IndustrialHeritage.

08.45 – 09.30 Tour at The Forsvik IndustrialHeritage and The Forsvik Shipyard Association.

09.30 - 09.45 The Progress of the MoSS Projectin 2001-2003. By the Coordinator of the MoSSProject, Curator Sallamaria Tikkanen, The NationalMaritime Museum of Finland, Helsinki.

09.45 – 10.05 What is visualization? ByProfessor Carl Olof Cederlund, Södertörns högskola(University college).

10.05 – 10.25 The MoSS project as a tool tocreate awareness of the protection of the maritimeheritage in the Netherlands. By Toon De Boer, NISA.

10.25 – 10.45 Coffee

Session III. The E. Nordevall projects and thevisualization perspective:

Chairman: Lars Bergström

10.45 – 11.05 The paddle steamer EricNordevall in its own time. By Chief of Staff of theSwedish National Maritime Museums, Hans-LennartOhlsson.

11.05 – 11.25 The underwater archaeologicaldocumentation and the salvage plans for the E.Nordevall 1980-2002. By Carl Olof Cederlund.

11.25 – 11.45 Eric Nordevall and the plans forthe salvage of the ship in the perspective of themotives in the Swedish Ancient Monuments Act.By the Head of Care of Ancient Monuments /Östergötland county, Bengt Häger.

11.45 – 12.00 Discussion

12.00 – 13.15 Lunch

Session IV. Means of visualization:

Chairman: The External Evaluator of theMoSS project, Dr Francisco Alves, Director of theInst. Portugues de Arqueologia. Centro Nacionalde Arqueologia Nautica e Subaquatica.

13.15 – 14.15 Visualization: Underwater Films:

The salvage of the engine of The Xantho. By RaySutcliffe, UK.

Wreck Sites and Underwater filming in the BalticSea. By Marko Röhr, Director, Matila & RöhrProductions Oy, Finland

14.15 – 14.55 Visualization: 3D Models in aDigital and Virtual World - its Use inArchaeology. By Kari Uotila, Associate Professor,Department of Archaeology, University of Turku,Finland

14.55 - 15.40 The visualization of shipwrecksthrough the arranging of underwater parks. By arepresentative of a national park service.

15.40 – 16.00 Discussion

16.00 – 16.20 Coffee break

Session V. The visualization perspective applied onNorth European shipwrecks:

Chairwoman: Sallamaria Tikkanen

The visualization of four well preserved ship wrecksin Northern Europe of different ages and in differingstates, treated by the MoSS project, preservedand visualized under differing conditions:

16.20 –16.40 Visualization, models &reconstructions and their use for both public andscholarly interpretation of the 16th century Britishwarship Mary Rose. By Christopher Dobbs, MaritimeArchaeologist, The Mary Rose Trust.

16.40– 17.00 The Burgzand Noord 10 Site: amerchant ship from the 17th century, preserved atthe Dutch coast By Project Director MartinManders, NISA.

17.00 – 17.20 From photos to measurementsand reconstruction – visualizing the Medieval DarssCog. By Head of the Agency of Preservation ofArchaeological Monuments, Hauke Jöns,Archaeological State Museum of MecklenburgVorpommern.

17.20 – 17.40 The Vrouw Maria - From wreck tovirtual wreck. By Stefan Wessman, The NationalMaritime Museum of Finland, Helsinki.

17.40 – Discussion

The general public at The Forsvik Industrial Heritageand Forsvik Shipyard Association will be

welcome to follow the lecture program. (During thisweekend is arranged the yearly Forsvik

Days with usually a big audience visiting the site).

19.00 – Excursion with steam sloops and dinnerfor the participants registering for this.

End of seminar

INFORMATION ON THE ARRANGEMENTS OF THE MoSS SEMINAR ON THE VISUALIZATIONOF SHIPWRECKS AND SHIPWRECK SITES IN STOCKHOLM AND FORSVIK THE 27TH TO THE28TH OF JUNE 2003

General program information:The seminar will start at the Vasa Museum on Friday the 27th of June 2003 at 1.00 PM and continue with theproceedings of this first day at the museum during the afternoon.After the end of the proceedings at about 4.30 PM the participants, that have registered for theMoSS bus transportation, will be taken by bus from the Vasa Museum to The Forsvik IndustrialHeritage and Shipyard Association, Karlsborg, at lake Vättern, about 4 hours drive south ofStockholm.The proceedings of the second day of the seminar will be held at the Forsvik site during Saturday the 28th. Theseminar will end with a dinner in Forsvik on the evening of the 28th of June.While the seminar is held in Forsvik at the same time the event “The Forsvik Days” (Forsviksdagarna) isarranged at the Industrial Heritage, with the presentation and visualization of the building of the paddle steamerreplica “The Eric Nordevall II”, exhibition and driving of old engines and many other arrangements. This event isvisited by a big number of visitors.Both at the Vasa Museum and at The Forsvik Industrial Heritage and Shipyard Association the generalpublic at these museum sites will be welcomed to follow the proceedings of the MoSS seminar.

Registration:The registration to the seminar is done by filling in and sending the registration form attached here to “KarlsborgsFästnings- och Turistbyrå” (see addresses for this at the same form).

The registration has to be done by the 30th of March 2003 at the latest in order that we can guarantee yourlodging.

Travels:The participants will arrange their own travel to Stockholm and back. The MoSS project will arrange free bustransportation to Forsvik on the afternoon the 27th and back to Stockholm after the seminar day in Forsvik on themorning of the 29th at 10.00 AM. The bus transportation is offered free of charge for those MoSS seminarguests participating that have registered to the seminar and to the same bus transportation (see registration formenclosed), as well as for MoSS representatives, session chairpersons and guest lecturers.

Lodging:The participants will arrange their own lodging in Stockholm, if necessary. Lodging during the nights between the27th and 28th and the 28th and the 29th of June, for the stay in Forsvik, can be booked through KarlsborgsFästnings- och Turistbyrå. See registration form for the booking of lodging.

Meals:There is a restaurant at the Vasa Museum for those who want to take their lunch there before thestart of the seminar at 1.00 PM.The Forsvik Industrial Heritage gives a special offer for meals during the stay in Forsvik. This offer includes alight supper at Forsvik at the arrival in the evening of the 27th, meals etc during the day of the 28th and a specialdinner arrangement on the evening of the 28th. (Those guests who want to accept this meals arrangement areasked to book for the same at the registration form enclosed). Breakfast is included in the hotel prices.

Karlsborgs Fästning ABAtt: Siw AdamsonAnkarvägen 2S-546 30 KarlsborgEmail-address: siwadamson@karlsborgsfastning.se

Registration Form forThe MoSS Seminar 2003 in Stockholm and Forsvik

(To be sent to the address above by mail or e-mail)

I will come to the MoSS Seminar

“Visualization of Shipwrecks and Shipwreck Sites”,

Friday the 27th at the Vasa Museum in Stockholm and at Forsvik Industrial Heritage and Forsvik ShipyardAssociation Saturday the 28th of June 2003.

Name: …………………………………………………………………………………….……..

Address: ………………………………………………………………………………………….

……………………………..……………………………………………………………………

…………….…………………………………………………………………………………….

Fax: …........………………………………

E-mail: …….......…………………………

I intend to accept the bus transportation from Stockholmto Forsvik on the 27th of June and back to Stockholm on the 29th:

Yes No

________________________________Signature

The Tourist Office in Karlsborg will organize accommodation in Forsvik.

If you are interested in this service, please fill out the hotel reservation form and send it together with thisregistration form to the same address the 30 of March 2003 at the latest.HOTEL RESERVATION FORM

(To be sent to the address below by mail or e-mail.)

Name:…………………………………………………Tel.: …........………………………

Address:..………………………………………………Fax:………........………………….

……………………………..………………………… E-mail:………….......…………….

Date of arrival: ______________ Date of departure:______________

Karlsborgs Fästning Phone: +46 (0)505 173 50Ankarvägen 2 Fax: +46(0)505 173 49S-546 30 Karlsborg E-mail:siwadamson@karlsborgsfastning.se

Accommodation for the MoSS Seminar “V isualization of Shipwrecks and Shipwreck Sites”,Forsvik 27-28-29 June 2003:

My reservation:

Hotel WetternNumber of double rooms: ___ Number of singlerooms: ___

Price for double room per night: SEK 795 Price for single room per night: SEK 595

Youth hostel ForsvikNumber of double rooms: ___ Number of singlerooms: ___

Price for double room per night: SEK 620 Price for single room per night: SEK 310

Youth hostel KarlsborgNumber of double rooms: ___ Number of singlerooms: ___

Price for double room per night: SEK 540 Price for single room per night: SEK 345All prices include breakfast.

Meals and registration fee in Forsvik:Dinner at the arrival 27.6, lunch, coffee etc. during the day of 28.6: SEK 410 Yes No

Evening of 28.6: A trip with steam launch at Forsvik and dinner: SEK 275 Yes No

Please tell us if you are vegetarian, or have any food allergy.

Special demands:

_______________________________________________________________________________________

Date/Signature

Newsletter1/2003

13

Dr. Christian Ahlströmdiscovered in the 1970sat the NationalArchives of Finlanddocuments concerningthe attempts to salvage

the wreck of the Vrouw Maria. Hepublished his results already in abook in 1979 (Ahlström 1979), forwhich he used Finnish, Swedish andDanish sources. These include a lotof information about the shipwreck,the cargo and the attempts to locateand salvage the wreck.

In 1999 the staff at the AmsterdamGemeentearchief checked archivesources in Holland for Dr. Ahlströmand Mikael Martikainen. The aim wasto find new information to ease thefinding of the wreck. A lot ofdocuments concerning the VrouwMaria, its shippers, insurance andvoyages were discovered. However,now at this stage of archaeologicalresearch, it seems that some of thesedocuments must concern an earliership with the same name.

The Maritime Museum of Finland inthe autumn of 1999 hired Dr. PavelKrotov at the St. Petersburg Universityto go through some Russian archives

to search for information about theVrouw Maria. Even though he wentthrough major archives both in St.Petersburg and in Moscow, theresults were marginal. The onlydocuments concerning the VrouwMaria dealt with that part of thesalvaged cargo, which wastransported to Russia via the city ofHamina. Furthermore he discoveredinformation about an earlier visit of theVrouw Maria to St. Petersburg in1770. In 2002 both Dr. Philip Kelsalland Birger Thomsen kindly checkedthe Sound toll archives and the “Tyskekancelli” archives in Copenhagen inorder to find to the Vrouw Mariarelated documents concerning theexceptions of customs for Royalpersons and embassies. However, nonew documents concerning the VrouwMaria were found.

Altogether this material was alreadyin year 2000 so extensive, that theMaritime Museum of Finland decidedto start a research project of maritimehistory about the contexts of theVrouw Maria. This project is lead bycurator Ismo Malinen, who is goingto do research on the shipwrecks ofDutch ships on the coast of Finlandin the 18th century in general. At the

moment the most important part ofthis project is research by Dr. OscarGelderblom at the University ofUtrecht. He will in the near future finishhis research on the reactions ofAmsterdam merchants and shipowners to the loss of a ship and itscargo. In this he uses the case of theVrouw Maria as an example. Theresults of this research will later bepublished in English. Dr. Gelder-blom’s research is financed by theDirectie der Oostersche Handel enReederijen, the Netherlands.

At the moment it seems that almostall relevant archives have beenchecked in order to find documentsconcerning the wreck of the VrouwMaria and its history. But, as thenotarial archives in the Netherlandsare so extensive, it’s still possible tofind new documents. Even withoutnew documents the case of theVrouw Maria will make possible aclose look at trade and shipping andpeople involved in this in the Baltic inthe 18th century.

References

Ahlström, C., 1979, Sjunkna Skepp.Lund.

D

Ismo Malinen,The Maritime Museum of Finland

Research in the history

of the Snow Vrouw Maria

MMMMMOSS

When I began therecons t ruc t i onwork of the wreckof the Vrouw MariaI stood in front of acompletely newproblem. I was

used to shipwrecks that were brokeninto hundreds of pieces, but in thiscase I had to deal with an almostcomplete wreck that was standingupright on a depth of more than 40meters. I realised that it was not,except for the rigging and the deckstructures, a question of recon-struction. It was more a question ofhow to document the ship so that onecould get significant data in the formof measurements etc. and thendecide the way in which one couldshow the Vrouw Maria for the generalpublic.

A computer program calledRhinoceros makes the reconstructionwork. I got familiar with the programwhile I was working at the Centre forMaritime Archaeology in Roskilde,Denmark. The program is a Cad-typeprogram that accepts a wide rangeof data types and is very easy to use.It draws ship curves particularly wellsince it uses NURBS geometry. Toget started with the work I got helpfrom Mr Fred Hocker (NMF) whokindly visited me in Finland and spenta week to start the reconstructionprocess with me.

The material I had at the beginningwas various data collected at the timewhen the Vrouw Maria was found in1999 and during the field seasons of2000 and 2001. It consisted ofmeasurements, still photos, videomaterial, a few Aqua Metre D100measurements, side scan sonar data,multi-beam sonar data and sedimentsonar data. With the help of thismaterial the shape of the wreck of theVrouw Maria started to take shape.

The Documentationand Reconstruction of the Wreck of

Vrouw Maria

Stefan Wessman, The Maritime Museum of Finland

W

At first I used all the availablemeasurements and then extracteddimensional data from the stills andvideo material. Next I added detailsfrom the video material. Finally thework reached a point where I had nomotive to continue without getting newdata (Fig. 1).

At the time of my reconstructionwork, the Maritime Museum of Finlandplanned the field season of 2002.During the reconstruction it was fairlyeasy to see what essential data was

still missing and had to be collectedduring the following summer. It soonturned out that we did not haveenough measurements from therigging and the deck level, and thatthe biggest problem was going to bethe measuring of the shape of the hull.Except for the length of the hull andan approximate height of the stemand sternpost, the only pieces ofinformation we had were those wecould see on the videotape. It wasobvious that we had to find anappropriate method for the measuring

14

Fig. 1. Reconstruction of the Vrouw Maria based on datacollected from the wreck site since 1999.

Newsletter1/2003

15

of the hull’s shape for the field season2002.

The Goniometer

Operating at a depth of approximately40 meters effectively cuts down thepossibilities you have whenperforming an operation like this. Youdo not even want to think aboutbuilding up some kind of measuringsystem down there. What you reallywant is a kind of system, which isfast, accurate, easy too operate, ifpossible cheap, and that does whatit is supposed to do. The mostamazing thing was that there actuallyexists a system like this - in NorthAmerica they have developed anideal system for measuring shapes.

In an article in the InternationalJournal of Nautical Archaeology(volume 27, 1998) J. Cozzi describesthe development and use of aninstrument called the Goniometer.This instrument determines timbercurvature in reference to otherstructures of the vessel. Basically theGoniometer is an inclinometermounted in an underwater housing.

The instrument had, in among otherplaces, been tested in the field inLake Champlain on a wreck calledWater Witch at the depth of 30meters, and in Lake Superior on awreck called Indiana at the depth of40 meters. Both wrecks have moreor less intact hulls and lie in deep,dark and cold waters. For us this wasan extremely important piece of newssince the environment in the GreatLakes along the US-Canadian borderis similar to the environment at thewreck site of the Vrouw Maria. Thiswas a fact that dramatically increasedthe chances for the method to workat our site.

We had two Goniometers for therecording of the hull of the Vrouw

Maria in 2002. During six dives twoteams measured hull sections, stemcurvature, stern rakes, the vessel’ssheer, and the position of theupstanding masts. The divers alsotook control measurements fordetermining the tilt of the ship.Altogether 257 measurements weremade.

The recording the Hull of theVrouw Maria

Recording the hull’s shape meansrecording cross sections of the shipfrom the gunwale to the keel. In mostcases it is of course impossible togo all the way down to the keel. Therecording process is simple: you holdthe Goniometer against the hull andwrite down the angle measurementsdisplayed. Then you move theGoniometer so that the next segmentstarts at the very spot where the lastended. This process goes on until youreach the bottom, or in best case,the keel. It would be possible to speedup the process if you could save theresults digitally instead of writingthem down, an improvement that weare working on at the moment.

The Goniometer was slightly modifiedfor our purposes. Since we did notwant to harm the wreck in any way

we at an early stage gave up the ideato mark the cross sections on thehull. Instead we added a verticalindicator to the Goniometer thathelped us to stay in line whenmeasuring from the gunwaledownwards. Fortunately theGoniometer left a very clear mark inthe silt, a mark we could use whenwe moved the Goniometer.

Because of the darkness at the siteit was necessary to use a light to beable to read the display. That againwas somewhat complicated since weused an acrylic pipe for theunderwater house of the former . Thelight was tested for pressure beforeuse and the house cracked a bitduring the test. The cracks and theround shape spread the light and itwas sometimes a bit difficult to readthe display. An inclinometer withhighlighted numbers on the displayis preferable. Another thing that wenoticed was that the spring used inthe push buttons on the goniometercould have been stiffer. At the depthof 40 meters, the pressure pusheddown the HOLD button for a coupleof times, which caused confusion.Except for these things everythingwent well and the recording processwas problem-free.

Fig. 2. The Goniometer, an instrument for the recording of curved forms.

MMMMMOSS

16

The Use of the Collected Data

Once you have the data collected bythe Goniometer, a fairly exactreconstruction of the hull is a simplething to do. Since the angle and thelength of the Goniometer are known,it is easy to calculate the shape ofthe hull. I will not explain the detailsabout how this is done. For those whoare interested I strongly recommendJ. Cozzi’s excellent article in whichthe whole procedure is described indetail (Cozzi 1998).

A part of the collected data hasalready been used in the recon-struction. Using the measurementstaken by the Goniometer we havecreated the form of the stem post asshown in Fig. 3. During thereconstruction work one sees rightaway if there are errors in themeasurements. An error can be dueto corrosion on the surface ordamage on the wood, but in any casea mistake is easily detected sincean inaccurate measurementimmediately sticks out.

When all the data collected during thefield season 2002 was processed wegot a hull shape that very muchstarted to look like a 18th centuryDutch ship (Fig. 4). The only part thatcaused problems was the sternbecause the shape changes so muchin the aft of the ship. A few more crosssections are needed here to getenough data for an exactreconstruction, and this informationwill be collected during our next fieldseason. My next step will be thereconstruction of the part of thebottom that cannot be measured.Then I can make line drawings on thebasis of the reconstruction.

Fig. 3. A verticalprojection plan of thestem post of theVrouw Maria,recorded by theGoniometer.

Fig 4. The shape of the hull of the Vrouw Maria as recorded by the Goniometer.

17

Newsletter1/2003

Visualizing

The reconstruction work has twogoals. One is to make a wire-frameversion of the Vrouw Maria that canbe used for scientific purposes suchas the performing of line plans,rigging plans or hydrostaticcalculations (Fig. 5). The same digitalmodel can also be used if one plansa salvage of the ship. The goalnumber two is to visualise the VrouwMaria for a the general public. Theplan is to show her not only the wayshe looks today as a wreck but alsothe way she looked as a sailing ship(Fig. 6). You have to remember thatthe majority of the public consists ofnon-divers who will never get thechance to see a wreck in its naturalenvironment. That is why one of ourfinal aims is to have a 3D virtual modelof the Vrouw Maria made.

References

Cozzi, J., 1998, The Goniometer: animproved device for recordingsubmerged shipwreck timbers. TheInternational Journal of NauticalArchaeology 27:1 (1998) 64-80.

Fig 5. A wire frame, digital model ofthe wreck of the Vrouw Maria.

Fig. 6. Reconstruction of the VrouwMaria in its original state made onthe basis of digital and otherrecordings of the same.

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18

In the summer of 1999 threelong-stemmed clay tobaccopipes were raised from theVrouw Maria’s cargo hold inorder to verify the date of theshipwreck. All three pipes werefound in the same place, just

below the rear edge of the main hatchof the hold. The cargo was coveredwith a vast layer of probablythousands of clay pipes.Unfortunately, no traces of thecontainers in which the pipes weretransported have been preserved. Thecontainers might have been barrelsor baskets.

All three pipes are unbroken exceptfor small pieces, which are missingat the end of the stems (themouthpieces) of the same. Of thethree pipes two have a markconstituted by a crowned B, and onea mark in the shape of a birdcage.The clay is discoloured in all of thepipes, especially in the pipes markedwith a crowned B. The dark brownishcolour is due to corrosion residues.

The pipe bowls are very similar inshape and size. The pipes with thecrowned B are identical except for theheight of the heel and the degree towhich the marks on them are visible,depending on their degree of finishing(Fig. 4). The oval-shaped bowls ofthese pipes are typical of Dutch claytobacco pipes of the latter half of the18th and early 19th century (Duco1982, p. 111 & Duco 1987, p. 27).

I

Clay tobacco pipes

Jaana Mellanen,Helsinki City Museum

from the Vrouw Maria

Fig. 1. The artist’s view of the hold of the Vrouw Maria. Drawing: TiinaMiettinen, The Maritime Museum of Finland.

Fig. 2. The three clay pipes raised from the Vrouw Maria. Photo: TheMaritime Museum of Finland

“All three pipes areunbroken except for

small pieces which aremissing from the end

of the stem”

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Future prospects

It would be of interest to study thelast phases of Bastiaan Overwesel’sproduction and trade because theyended just a little before the VrouwMaria’s fateful journey fromAmsterdam to St. Petersburg in1771. Further samples of claytobacco pipes from the ship’s cargowould also tell us more about the tradeconnections and the dating of themakers’ marks in general in theDutch clay pipe production.

References

Duco, D. 1982, Merken vanGoudse pijpenmakers 1660-1940.Uitgeversmaatschappij DeTijdstroom B.V. Lochem.

Duco, D. 1987, De Nederlandsekleipijp. Handboek voor dateren endetermineren. StichtingPijpenkabinet. Leiden.

Van der Meulen, J. 1994, De“gecroonde roos” en anderepijpenmakersmerken van Gouda.Pijpelogische Kring Nederland.Leiden.

Discussion by letter and by e-mailon 1.7.2002 and 14.8.2002 with Mr.Don Duco.

The two pipes with a mark in theshape of a crowned B

The inscriptions on the stems of thepipes with a crowned B aresomewhat unclear. However, thereare sufficient amount of letters tosuggest who the maker was ( …RW… /…ERWE…) and to identifythe place of production. (…UD…/…OUIN…). In both pipes a coat ofarms appears on the side of the heelbut the number of dots and otherdetails are difficult to make out.

The crowned B was used by BastiaanOverwesel at some point of time inhis active years 1737 -1770 in Gouda.The letter “B” was also used by a JanOverwesel (van der Meulen 1994, p.62). All the same, the size and shapeof The Vrouw Maria’s pipe bowlsindicate that they are from a laterperiod than his active years 1730-1746. Bastiaan Overwesel wasprimarily a merchant and othermakers made his pipes on hisrequest, which explains the variationsin quality. The coat of arms on theside of the heel of these two pipes isthe arms of Gouda (Duco in e-mailmessage on 14.8.2002).

The pipe with the mark in theshape of a birdcage

The overall quality of this pipe isbetter than in the pipes with thecrowned B. There is a maker’s mark- “boogkooi” - stamped on the bottomof the heel, which is a chaffinch’scage, and a relief mark on the side ofthe heel. In 1739, the pipe makers’guild in Gouda ordered its membersto add the arms of Gouda on the sideof the heel to distinguish the pipesmade in Gouda from pipes made inother towns. In 1740, the letter “S”was added to mark an ordinary pipe.The best quality pipes were leftwithout the letter (Duco 1987, pp. 77-78).

At some point in time, a pipe makercalled Jan Soufree used the“boogkooi”. His active years span from1732 to 1796, the year of his death(Duco in e-mail message on14.8.2002). The same pipe maker ismentioned in Jan van der Meulen’scatalogue (1994, p. 69) as JanSouffreu whose active years were1732 - 1782 (qualified to guild in18.10.1732). The “boogkooi” was alsoused by an Anthony Souffreusometime between 1730 -1760 (vander Meulen 1994, p. 69).

The inscription on the stem is veryclear: SOUFRE(E/U) IN GOUDA. Themakers’ name on the stem of a pipebecame more common in the secondquarter of the 18th century, but someearly examples of such inscriptionsdate back to the latter half of the 17th

century (Duco 1987, p. 83).

Fig. 4. The profiles of the bowls ofthe three salvaged pipes. Of these onehad a mark in the shape of a birdcage,and two a mark in the shape of acrowned B. Drawing: Jaana Mellanen.

Fig. 3. Mark in the shape of a birdcage on one of the pipes. Photo The Maritime Museum of Finland.

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What’s on?The BZN-10 Site

Martijn Manders, NISA

hat’s on:

Introduction: TheN e t h e r l a n d sInstitute for Ship-and underwater-

Archaeology (NISA) is within theproject responsible for the work doneon the Burgzand Noord 10 wreck(BZN 10); a seventeenth centurytrader that sunk on the Texel Roads.More information about this wrecksite will follow in the 4th issue of theMoSS Newsletter.

Monitoring: The datalogger has beeninstalled in the wreck in June. Thestrategy was to install one dataloggeron the wrecksite and to exchangethis one after a few months for thesecond datalogger. In this way wewere able to test both loggers beforeplacing, cleaning and callibratingthem. With the spare logger we havebeen testing on other sites to see ifwe could find differences on differentwrecks. The first datalogger has beenworking well except for a few softwareproblems. The second dataloggerhowever had more severe problemsand it had to be sent back to theproducer. After that, the firstdatalogger has been on site untilDecember the 17th 2002.

At the same time in June when thedatalogger was installed, alsowoodblocks for aerobic and anaerobicdegradation research (short, middleand long term degradation) wereplaced on the wreck as well ascellulose (shirley textile, short termdegradation). Samples after 3 monthsand 6 months have already beenretrieved from the wrecksite and sentto the MRAS for analysis. Uniqueabout the BZN 10 wreck is the factthat it is protected againstdegradation and covered up withgauze. The wood and cellulosesamples have been given the same

condition as the wreck. By doing this,hopefully, we can find out if this kindof protection is valid and functional.

In 2003 we will have to change thedataloggers and retrieve samples forfour times.

Also visual monitoring of thewrecksite has been undertaken. Atthe same time, areas that had beenexposed were covered as well.

Safeguarding: The Wadden Sea isstill on the Tentative List for theUnesco World Heritage Sites. It is notyet known when it will be accepted.

The wreck is physically protected bygauze. This (scaffolding) gauze letsthe sand through, but due to a lackof current under it, the sand settlesand builds up an artificial reef. Theconclusion of our visual monitoring isthat this method works very well. Thewhole wreck is covered with a thicklayer of sand. The seabottom aroundthe wreck is lowering rapidly.

In 2003 the protection of the wreckwill be visually inspected every thirdmonth.

Visualizing: In 2002 we have madeside scan sonar and multibeam sonarimages. This will have a follow up in2003. In this way we will be able tomonitor the erosion around the wreck.The idea was also to measure thecurrents around the wreck and torecord them. However due totechnical problems this is postponedto 2003. Natural erosion seems to bethe biggest threat to the wreck site.

For the monitoring theme also videofilms and photo’s have been made.

In the summer 2002 our Germancolleagues of the MoSS project havevisited us to test their photographic

mapping method in the Wadden Sea.Unfortunately the conditions hereseem not to be appropriate for thismethod since the visibility is too badand the suspension in the water toohigh. The tidal movements with strongcurrents make it only possible to divefor a short time.

All actions above water have beendocumented on video and digitalphotography as well.

This will be continued in 2003.

Information to the general public,students and specialists: During2002 we have worked intensivelytogether with Sven Ober, a specialistin dataloggers from the NetherlandInstitute for the research of the Sea(NIOZ) and with the people workingon the EU-project BACPOLES.Some samples of wood have beengiven to Dr. Wolff from the GroningenUniversity to investigate it on theexistence of woodboring organisms.

Lectures have been held at theDEGUWA conference in Aachen andthe symposium held by the MoSS-project in Schwerin (Germany). Aposter has been shown on theReuvens symposium in theNetherlands.

Interviews have been given for nationaland local newspapers and television.

Different articles have been writtenabout this subject for colleagues andthe general public.

In 2003 we will present the project atdifferent symposiums in theNetherlands (DEGUWA, Reuvens),Danmark (ISBSA), Sweden (MoSSInternational Seminar) and hopefullyothers.

Newsletter1/2003

21

he paddle steamerE.Nordevall (1836-1856) is the shipwreckof Sweden within theMoSS Project and itsthree main themes.

The Shipwreck Project E.Nordevall isat the same time treated anddeveloped by several other parties.

The management and the protectionof the wreck as such rest with theCounty Administration of the countyof Östergötland because the ship issituated within the borders of thiscounty. The main activities of theCounty Administration are related tothe preservation and safeguarding ofthe wreck, its protection as a uniquesite, for example. Due to damage,diving has been prohibited at the sitefor a couple of years now. The site isunder the supervision of the countyauthorities.

There are ongoing plans to salvagethe wreck of the E.Nordevall in orderto preserve it and exhibit it in amuseum in the town of Motala on theeast side of Lake Vättern. A specialgroup is developing this matter. As apart of the preparations, the SwedishNational Maritime Museum hasrecently performed underwaterrecording on the site to collectinformation about the ship’ssuperstructure. There are pieces ofthe superstructure lying around thewreck on the bottom of the lake.

The Swedish Central Board ofNational Antiquities has given itsprincipal permission to salvage theship – under the condition that thecosts of the operation in all its phases(from the salvage to the museumexhibition) are covered from the verybeginning. In addition to this, thequestions concerning the premisesand the arrangement of anE. Nordevall Museum must be solved

before the salvage project can belaunched.The National MaritimeMuseum of Sweden shares thisopinion.

A project recreating the E.Nordevallas a full-scale replica was launchedat the Forsvik Industrial HeritageCentre on the western shore of LakeVättern in the middle of the 1990’s.This project, which is managed by theForsvik Shipyard Association, is atpresent far advanced. In the fall of2002 one has started to put upboarding planks on the frames. Theiron parts of the engines have beenforged, and preparations to mountand test the two engines at the MotalaVerkstad have been made. The originalengines of the E.Nordevall were builtin this mechanical factory in the1830’s.

The goal of the Project Eric NordevallII is to have the replica in passengerservice on the Göta Canal, on the oldroute of the original paddle steamer.

One important aim within this projectis to reconstruct and visualize one ofthe first paddle steamers in Swedishwaters and to give the general publicthe possibility to experience a journeyon a ship like this. The visualizationof the time period in question is animportant issue in the project as well.These issues were under discussionat a seminar at Forsvik. A seminarreport has been printed (Cederlund,C.O., (ed.) 2002. Hjulångfartyget EricNordevall under byggnad och underånga Nessebro).

Extensive reconstruction work hasbeen done to build the replica as atrue copy of the original. Specialattention has been put on the buildingmaterials and on those features thatreflect the circumstances of the lifeon board this kind of a vessel. Forthe reconstruction, complementary

documentation has been made onthe shipwreck to get a better ideaespecially of the structure and thefittings of the interior of the ship.

“The goal of the ProjectEric Nordevall II is to have

the replica in passengerservice on the Göta Canal,

on the old route of theoriginal paddle steamer.”

If the original ship is salvaged, theintention is to have the two projects– both the museum in Motaladisplaying the preserved original andthe replica in passenger service onthe old routes of the ship - supportand complement each other in thevisualization of the vessel and its era.

Within the MoSS Project, the workon the E. Nordevall will concentrateon an evaluation of the differentactions developed concerning theship and its preservation. The replicaproject is under evaluation as well.Because the wreck was located 22years ago, and has been underresearch since then, we now have anoteworthy amount of documentedinformation. This means that we candiscuss the three main themes of theMoSS Project in a generalperspective. In addition to this, wecan reach general conclusions byusing the experiences that aregathered by the different bodiesworking on this now well-knownshipwreck in one of Sweden’s largestand deepest lakes. An account of thecollected information is under work,and it will be seen in the MoSSProject Report.

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Carl Olof Cederlund,Södertörns Högskola

and it’s developments 2001-2002

What’s on?The E. Nordevall project

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ithin the MoSSProject, theresearch unit of theArchaeologicalstate museum ofM e c k l e n b u r g -

Vorpommern is responsible for thedetailed investigation of a cog fromthe late 13th century, the so calledDarsser Cog. The investigations onthe Darsser Cog site will be describedin detail in the third issue of the MoSSNewsletter.

Documentation

Innovative technologies were used forthe documentation and visualisationof the Darsser Cog. By the help ofnew radar and sonar technology, wewere able to visualise the structureof the wreck above and under the seabottom in April 2002. In other words,we managed to record the submergedstructures of the wreck. Theseinvestigations give us a detailed viewof the surroundings of the wreck andof those parts of the wreck that arecovered in sediment. We will continuethese investigations in the spring of2003.

Excavations

After having investigated the sedimentaround the wreck, the fore ship wasexcavated from the stem to the maststep in 2001 and 2002. Especially thestarboard side is very well preserved.It is nearly complete, and it waspossible to study the stemconstruction and the V-shapedframes as well as the planks in detail.The removed sediment wasinvestigated carefully, too. In order toget even the smallest finds, thesediment was sifted. During theexcavations, remains of the cargo,the equipment, and the personalbelongings of the crew members wererescued. These finds tells us about

trading contacts and life on board. Theexcavations will be finished in August2003.

“Although the shipwormTeredo navalis has

infested the upper parts ofthe wreck badly, the cog

shall not be lifted butsafeguarded at the site.”

Visualising by photogrammetry

Within the MoSS Project, thedevelopment of the routines forphotogrammetrical documentationand measuring of shipwrecks is animportant goal. We hope that in thefuture the photogrammetry of shipwrecks leads directly to thevisualisation and finally to the virtualreconstruction of the wrecks. Duringthe fieldwork at the Darsser Cog site,all visible and excavated parts of thewreck were documented byoverlapping photos. To connect thesepictures and to process the data, weused computer programs such asAutocad and Photo Modeller. InWinter 2002/2003 these pictures willbe worked out and combined for thereconstruction of the Darsser Cog.

Monitoring

The Darsser Cog is also a part of themonitoring theme of the MoSSProject. In August 2002, wooden andtextile samples were placed at thewreck in order to give us informationabout the biotic factors at the site. Atthe same time we placed data loggersto collect environmental data. The firstpieces of information from the loggersand the samples were taken inNovember 2002. Till the end of theproject, data will be collected atregular intervals.

Safeguarding

Although the shipworm Teredonavalis has infested the upper partsof the wreck badly, the cog shall notbe lifted but safeguarded at the site.That is why the wreck was refilled withsediment and covered with fleecematerial and sandbags. Finally it waspartly covered by specialpolypropylene gauze. The same kindof gauze has been in use in theNetherlands for a couple of years now.

Information to the general public,students and specialists

The results of the MoSS research atthe Darsser Cog are presented to thepublic in different ways. There areexhibitions at the Darssmuseum inPrerow and at the Museum forUnderwater Archaeology in Sassnitz.In addition to this, there have beenreports about the wreck site innumerous newspaper articles as wellas in radio and TV shows. A directconnection between the protection ofthe Darsser Cog as a part of maritimeheritage and the protection of themedieval Hanse towns was shown ina series of lectures that wereorganized as an accompanyingprogramme for the exhibition “Firedhistory – The ways to the gothicarchitecture built in brick”. Theexhibition was about the importanceof the Hanse, and it was staged inLübeck, Wismar, Rostock, Stralsund,Neubrandenburg, and Greifswald.

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What’s on?The Darsser Kogge Site

Hauke Jöns, Landesamt für Bodendenkmalpflege undArchäologisches Landesmuseum von Mecklenburg-Vorpommern

Foto: Juha Nurminen

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Newsletter1/2003

he first MoSS Seminarwas held in Schwerin,Germany, on Sundaythe 10th of November.The seminar focusedon the different

possibilities we have to documentshipwreck sites. A special emphasiswas put on modern technologiessuch as photogrammetry andgeophysical measurement. Theseminar took place in the residenceof the parliament of Mecklenburg-Vorpommern, in the Castle ofSchwerin. The seminar was open forthe general public, and about 70persons from eight countries(Sweden, Denmark, Finland,England, Portugal, the Netherlands,Germany and Poland) joined theoccasion.

On behalf of the Minister ofEducation, Science and Culture ofMecklenburg-Vorpommern, U. Pet-schulat welcomed the audience andpointed out that the management ofthe common underwater culturalheritage is a good example of theneccessity of international co-operation and the exchange of ideasand knowledge. Petschulat wasfollowed by Senatsrat J. I. Weber whogave an overview of the actual andfuture possibilities of getting fundingfor underwater cultural heritage fromthe Culture 2000 program and otherprograms.

In the first session of the seminar, theMoSS project coordinator S.Tikkanen described the structure, themethods, the aims, and the scientificgoals of the MoSS Project. Her lec-ture was followed by a shortcharacterization of the MoSS wrecksites in Finland (the Vrouw Maria byM. Leino), in Germany (the DarsserCog by H. Jöns), in Sweden (the EricNordevall by C.O. Cederlund), and inthe Netherlands (the Burgzand Noord10 by M. Manders).

During the second session, thedifferent documentation techniquesused at the MoSS wreck sites wereintroduced. The session started withthree lectures about the Darsser Cog.First F. Lüth told the audience aboutthe practical experiences of the surveyand documentation at this site. Thiswork is done by aerial photography,side-scan-sonar, sediment-sonar andgeoradar as well as by drawings,videotapes, and photographs. Thelast part of his lecture was about therequirements of underwaterphotogrammetry.

At this point S. Brozio took over andsummarised the principles of theunderwater photogrammetry and theproblems of the data processingbased on Autocad. Autocad is aprogram that enables us to make aprecise reconstruction of adocumented wreck. Brozio wasfollowed by P. Korduan who told usabout his experiences in the use of aprogram called Photo Modeller. Theprogram is used for the 3D-reconstruction and thephotogrammetrical measurement ofthe Darsser Cog.

The next lecture was given by M.Leino and S. Wessman who gave areport about the documentation of theVrouw Maria site with the Video RayPro mini-ROV and the underwaterpositioning system AquaMeter D100.The following lecture was about thedocumentation routines developed bythe Netherlands Institute for Ship andUnderwater Archaeology (NISA) for

shipwreck sites in the Wadden Sea.The lecture was given by M. Manders.The lectures about the wreck sites ofthe MoSS Project were finished by areport from C.O. Cederlund about theunderwater documentation of thepaddle steamer E. Nordevall inSweden in Lake Vättern in the years1985-1989.

In the third session of the seminar,five experts from Sweden, Denmark,England and Portugal gave anaccount of their experiences ofdifferent documentation techniques.L. Einarsson started with a lectureabout the twenty years of research,excavation, and recording of theSwedish wreck of the warship Kronanfrom the 17th century. In the nextlecture A. Olsson informed us aboutthe aims and the recording strategiesfor the documentation of the so-calledGöta wreck, a wreck that was foundin Gothenburg some years ago.

The following lecture was given by J.Dix who presented new geophysicalmethods for the survey and the non-destructive investigation of submergedarchaeological sites based onacoustics. The next report was givenby A. Englert who described therecording and documentationtechniques used at the medievalKarschau wreck site. The wreck wasfound near Schleswig, on the bottomof the Schlei. Finally F. Alvessummarised his experiences of themanagement of the underwatercultural heritage in the coastal watersof Portugal.

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The First MoSS Seminar in

Schwerin, Germany.What Happened?

Hauke Jöns

Editor: Carl Olof CederlundSödertörns högskola(University College)Box 4101, SE - 14104Huddinge, SWEDENPhone +46 8 608 4201Fax +46 8 608 4080carl-olof.cederlund@sh.se

Layout: Jaakko NygrénPhone +358 9 4050 9072jaakko.nygren@nba.fiMMMMMOS

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Publisher:The National Board ofAntiquitiesPL 913, FIN-00101Helsinki, Finland

what’s on?meetings & seminars

Published quartely with the support of the Culture 2000Programme of the European union

This project has been carried out with the support of the European Community. The content of this project does not necessarily reflect the position of the European Community, nor does it involve any responsibility on the part of the European Community

newsletter

MeetingsThe project meetings act as our internal communication,and the meetings are held mainly by the project participantsthemselves. In the meetings the partners discuss the projectin detail, make plans for the future, and develop the generalidea of the project. The participants discuss the differentthemes of the project and/or one theme at a time. Additionally,the aim of the meetings is to evaluate the project and discussthe many practical and scientific questions that are raised inthe course of the project. The different themes can bediscussed, if needed, in sub-groups. Our plan is to have twomeetings per year: one in the beginning of March, and anotherin the beginning of November.

Indicative timetable of the meetingsThe fourth meeting March 2003The fifth meeting November 2003The sixth meeting March 2004

SeminarsOur plan is to have three seminars; the first seminar hasbeen held in Germany on Sunday 10th November 2002(theme: the documentation of shipwreck sites andphotogrammetry), the second will be held in Sweden in 2003(theme: the visualization of shipwreck sites), and the third inthe United Kingdom in 2004 (theme: the monitoring andsafeguarding of shipwreck sites).

Seminars are bigger meetings with external experts and awide range of lectures that bring extra expertise into theproject. The seminars last for three days; they begin on aFriday and continue on Saturdays and Sundays. Seminarsare open for the general public, which is why they arescheduled on weekends. At each of the seminars, five expertsare invited as special advisors and lecturers. The expertsare specialists on underwater documenting, visualizing,monitoring and management.

The aim of the seminars is not only to provide the partnersand the general public with information and expertknowledge but also to produce dialogue between the differentgroups who have an interest in the management andexploitation of the underwater cultural heritage. The seminarsare intended for the general public and the media as well asfor the students and cultural operators and professionals ofunderwater cultural heritage.

Indicative timetable of the seminarsThe second seminar will be held in Swedenin 27-28 June 2003.(theme: the visualization of shipwreck sites).

The third seminar will be held in the UnitedKingdom in the spring of 2004(theme: the monitoring, safeguarding and managementof shipwreck sites).