Do fundo do mar... Sea bottom

February 27, 2007


In the April 2006 issue of the International Journal of Nautical Archaeology, Texas A &M University archaeologist Alexis Catsambis described a longforgotten report on the first underwater archaeological survey.

In 1884, the Archaeological Society of Athens attempted a survey of the Straits of Salamis.

Using Greek divers, the team attempted to locate shipwrecks associated with the sea battle of 480 B.C. when the Greek fleet defeated the invading navy of the Persian King Xerxes.

The report languished in obscurity for so long probably because it was, according to the society’s secretary, "a complete failure."

Bad weather impeded survey efforts, and even when divers found something interesting, attempts to excavate it stirred up so much sediment that "the waters immediately become blurry and the diver remains in the dark."

Catsambis writes that, in spite of the lack of results, the survey is a neglected landmark in the history of archaeology.

"The scientific practices that were adopted during this pioneering expedition … are still valid," and modern investigators, building on this foundation, have developed methods to overcome the obstacles encountered by the Greek team.

A perfect example of these new methods is a report on an archaeological survey in Lake Erie just published by the Ohio Department of Natural Resources. The Lake Erie Geology Group used side-scan sonar to locate and map shipwrecks surrounding Kelleys Island.

The Ohio team encountered some of the same problems experienced by the Greeks. During the two-week survey, weather conditions prohibited work on all but five days.

In contrast to the Greek survey, the ODNR team described its study as a success. The members discovered possible new shipwrecks and mapped the wrecks of the George Dunbar, Amaretta Mosher and F.H. Prince.

The ODNR report is a pilot study. It concludes with several recommendations for future work. The Maritime Archaeological Survey Team plans to follow up with investigations of the new sites. The survey team is an all-volunteer group that won a 2006 Ohio Lake Erie Award from the Ohio Lake Erie Commission.

In this light, the efforts of the Archaeological Society of Athens don’t seem like such a failure. Isaac Newton once wrote, "If I have seen further, it is by standing on the shoulders of Giants."

ODNR’s success is due, at least in part, to the hard lessons learned by the Greeks in 1884.


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Sharjah: The UAE's rapid progress and social development are built upon its unique history, rich civilisation, heritage and deep-rooted culture.

Recent discoveries and excavations have shown that the UAE lies on a treasure of archaeological and historical sites, which prove that man lived along coastal areas thousands of years ago.

Among the archaeological and historical sites that the UAE is endowed with are: castles, forts, watchtowers and places of worship, WAM reported.

Coastal areas
By examining the findings of the excavations, archaeologists have discovered that the UAE has witnessed the settlement of human inhabitants dating back to the civilisations of Old Egypt and Meso-potamia - the Land of Two Rivers.

The country's coastal regions are considered to be of the most significant areas populated by humans, because they have archaeological and historical treasures that span the Stone Age, Bronze Age and Iron Age.

The historical study of those areas also provides important information about the environment of the UAE's coastal areas and is a crucial link to understanding patterns of human settlement thousands of years ago.

Although some areas are subject to extensive surveys and deep excavations, there are others that have still not received enough attention. More excavations and research are needed in order to put together a clearer picture of the country's rich history.

Among the areas needing more attention is Al Fisht village, which lies on the coast, one mile northeast of Sharjah.

Lost village
Researchers, travellers and books often mention it, but the question remains - what available information and facts about Al Fisht village can be extracted from the stories and tales told by forefathers to their children?

According to those tales, the village sank into the sea more than 30 years ago after it was hit by strong Shamal winds and high sea waves, causing its residents to move to Kalba, Umm Al Quwain and Ajman after their houses and farms were flooded.

This is an indication that there are many archaeological ruins that have sunk deep into the Gulf waters. Hence, Al Fisht village is just as important as other areas in which archaeologists have been tracing the earliest human settlements and historical sites.

This is important to consider since the absence of detailed information is often interpreted as a lack of history.

Those sunken treasures need to be unearthed by archaeologists and researchers who can help shed more light on the UAE's history and civilisation.

The sinking of the Vasa, the famous Swedish 17th century warship, was not the fault of King Gustaf II Adolf's meddling, according a new book.

The monumental work, the first volume in a multiple series, clears up former misunderstandings and popular myths about the doomed fate of the mighty ship on its maiden voyage.

The Archaeology of a Swedish Warship of 1628 proves that contrary to popular myth, the ship was built to its original specifications and not modified in the middle of construction. Many people believe that the instability of the ship was caused by the King, Gustaf II Adolf meddling with the design by adding an unplanned second gun deck.

The other most notable fallacy debunked by the book is the notion that Vasa was lost and forgotten for its 333-year rest in the Stockholm Harbor. Volume I indisputably demonstrates that there were several salvage attempts long before the successful raising of the ship in 1961. There are also several historical references to the wreck of the Vasa on Stockholm sea charts.

The principle author, Professor Carl Olof Cederlund , took part in the excavations and successful salvage effort. The first volume focuses on the ship’s colorful history and monumental effort to raise the sleeping giant. It has over 400 illustrations and includes construction plans of the ship.

The Vasa sank in 1628 on its maiden voyage. It lay at the bottom of Stockholm’s harbor for 333 years before it was raised amid great fanfare. It’s on display at the Vasa Museum in Stockholm.

The partially submerged Liman Tepe, a major Early Bronze Age harbor town located in Izmir’s Urla district, possesses the world’s oldest breakwater, said archaeologist Professor Hayat Erkanal during a press conference last week. Breakwaters, an important part of modern nautical life worldwide, are constructed on or near coastal areas as a defense from incoming waters that protects ships as well as land from harsh weather and high tides.

Erkanal, who is also the president of Ankara University’s Underwater Archaeological Research Center, has been the head of this excavation site since 1992 and presented information about the excavations at a press conference together with Urla Mayor Selçuk Karaosmanoglu.
Erkanal said their excavations continued both on land and underwater and their aim was to explore the hidden parts of the settlement buried underwater. “Excavations indicated that Liman Tepe had interaction with different cultures and was a corridor for numerous cultures due to its geographical situation as well as its port, an important spot for overseas trade and multilateral cultural interaction at the time. The whole harbor complex is buried underwater today and our aim is to uncover the complete port complex and settlement hidden underwater.”

Liman Tepe is a major prehistoric settlement that was inhabited from the Neolithic Age until the end of the late Bronze Age, continuing into the Classical Age. Professor Guven Bak?r and Erkanal carried out the first archaeological digs at the site in 1979, and a team led by Erkanal under the auspices of Ankara University’s Archaeology department is conducting the current excavations.

Erkanal further noted that their underwater work indicates that Liman Tepe has the world’s oldest breakwater, which was built to block the strong north winds and as a natural part of the city wall. He said their work also included geological research aimed to reveal the physical changes of the sea level and ground as well as the region hosting the Liman Tepe settlement throughout history.

“Our excavations in the settlement focus on Early Bronze Age remains. The settlement was surrounded by a monumental city wall and consisted of two cities: downtown and an Acropolis, which included a palace-like structure representing political, economic and religious power,” he noted.

According to Erkanal, the most significant finding from last year’s excavations was part of an anchor, which is made of wood and metal, and indicates evidence of marine activities.

He added that they had previously unearthed a sunken ship found during excavations and is now ready to go on display at the Underwater Archaeology Museum to be opened in Urla. “We want to list all the underwater treasures of the area in an inventory and also to open the excavation site to the public.”

Urla, a district of Izmir, is located on the road to Cesme from Izmir and lies 38 kilometers west of Izmir. The district used to be an important cultural center in ancient times and was originally the site of the Ionian city of Klazomenai, with probably the most ancient and regularly used port in the world. The excavated artifacts and sculptures are currently exhibited in the Louvre, Athens National Museum and Izmir Archaeology Museum.

Off Goa’s coast, maritime archaeologists are currently diving to explore the remains of an ancient steam engine shipwreck near Marmagao, about two km away from the oldest shipwreck found here in 1988. They suspect it will take three years to piece together the story of the new find from evidence like furnace bricks probably used to cook on board. But they could even find ivory and ancient guns.

At the same time in Lisbon, Portuguese archival authorities are scanning documents of maritime trade between the two nations to pass on tips to the National Institute of Oceanography (NIO) in Goa, to help locate an estimated 40-odd ancient shipwrecks along the Goa to Karnataka coast. This year the search will also extend around Orissa and Andhra Pradesh.

“In the coming days, we will conduct explorations of shipwrecks around Goa waters,” NIO maritime archaeologist Sila Tripati told HT. “We have also requested Portugese scholars in Lisbon and South Africa for data to help us explore shipwrecks at the Orissa and Andhra coast too.”

On February 10, Tripati and Ian Godfrey from the Western Australian Museum published results in Current Science on the 1988 find of a Portuguese cargo vessel that sank in the 17th century near Marmagao. They based their findings on eight soft, decaying elephant tusks and nine hippo canines from the wreck. Nothing remained of the ship’s body or archival documents, so scientists depended on the haul of two-metre-long iron guns, Chinese ceramics and bricks for more clues. “The tusks and teeth are evidence of historic maritime trade between Goa, Portugal and Africa,” the duo reported.

“Radiocarbon dating conducted in Lucknow indicates the ivory is 360-400 years old,” said Tripati. While the 1988 wreck remains mysterious, maritime archaeologists from Australia, South Africa to the US are in touch with NIO to know more about what lies on Goa’s seabed.

HUTCHINSON ISLAND -- Treasure hunters arrived on the Treasure Coast on Monday in search of what they hope might be a ship from a gold-filled fleet that gave the area its name.

The four-person crew of a lift boat named the Polly-L expects to reach Tiger Shores Beach, located just north of Stuart Public Beach, this morning and begin looking for historical artifacts associated with a shipwreck possibly from the 1715 Spanish treasure fleet.

The search begins four years after officials with the Amelia Island-based Amelia Research and Recovery team first surveyed the shallow waters off Hutchinson Island for a stack of cannons that a local surfer discovered almost 30 years ago.

"I'm excited and ready to go," said Dave Jordan, a former Palm City resident and surfer who kept his discovery a secret for 25 years until his wife triggered the memory. "I want to see what's there."

So does Doug Pope, the president of Amelia Research and Recovery, who on Monday captained the four-story-high boat down the Intracoastal Waterway in Fort Pierce.

Pope and Jordan worked with the state to secure necessary permits to "dig and identify" the 42 targets they found during a 2005 survey about 200 yards from the beach.

Starting as early as today, professional divers will use metal detectors to rule out which of the targets are "modern junk" -- bridge parts or other metal debris -- picked up in the initial survey, Pope said.

Then they'll use a 6-inch vacuum dredge to determine what the remaining targets are. If they uncover an artifact of potential historical significance, the treasure hunters must first receive a permit to "salvage" the material.

"When the treasure gods start smiling, then we'll say we found something," Pope said. "They don't smile that often."

If Jordan's memory turns out to be accurate, Martin County historians say the shipwreck could be part of an 11-vessel Spanish fleet that wrecked in a hurricane in 1715.

So far, the ship from that fleet discovered farthest south was the Urca de Lima, found north of Fort Pierce's Pepper Beach Park, which now contains a state underwater archeological preserve around the wreck. Other ships from that fleet have been discovered in Indian River County.

While it is unlikely any gold will be uncovered in the search, officials with the Historical Society of Martin County are hoping historical treasures will be discovered and eventually displayed in the new Elliott Museum planned just yards from the possible shipwreck site.

Jordan, who has family in Martin County and is in the process of moving from North Carolina to Gainesville, said he will likely stay on the Polly-L for a few days as the work begins. The project is expected to take about a month.

"It's important for me to find the cannons, but it's not about me," he said. "I'm excited Martin County is getting a chance. There's tons of history here. It's unbelievable."

A 2,000-year-old log boat discovered buried in mud is to be put on display after a 10-year restoration project.

The Iron Age vessel was found in 1964 during dredging work in Poole Harbour and members of York Archaeological Trust restored the water-logged timber.

The log boat, which is thought to have been used for continental trade, is estimated to have weighed 14 tonnes.

A glass case has been designed to house the ancient timber, which is due to be displayed in Poole museum in June.

The final cleaning of the vessel has been scheduled to finish this month.

Sweet cleaning
The log boat, which carried up to 18 people, would have been based at Green Island in the harbour.

After it was found it was kept submerged in water for 30 years while archaeologists decided what to do with it.

As part of the conservation project, the boat has spent a decade soaked in a sugar solution before being dried out at Poole's Scalpel's Court museum.

Councillor Elaine Atkinson said: "The log boat has international and major historical importance.

"It is more than 2,000 years old and represents an important part of Poole's maritime history."

COLUMBUS - The George Dunbar left Cleveland at 6 p.m. on June 29, 1902, bound for Alpena, Mich.

Loaded with coal, the 136-foot ship rode low in the water as it steamed northwest into rough Lake Erie weather, her boilers running full steam.

By nightfall, the Dunbar struggled past Kelleys Island, the wind and waves pulling at her seams. In the darkness, the ship began to take on more water than her crew could pump out. To lessen the strain, the Dunbar's skipper turned his ship into the wind.

But she already was lost. At 4 a.m., her hull split.

The skipper, his wife and daughter escaped the Dunbar, but seven crew members were lost to Erie, which has claimed an estimated 2,000 ships.

The Dunbar has survived more than a century of summer squalls, November gales and winter ice, and the shipwreck remains preserved 45 feet below the surface, just over the international line in Canadian waters.

In 2003, Dale Liebenthal cruised over the wreck and took a ghostly picture of the ship, still heavy with coal, revealing her stern, bow and bulwarks. Her smokestack lies broken, about 40 feet off the port stern.

Liebenthal led a team of state Geological Survey scientists in a pilot study using a tool called side-scan sonar to produce images of 25 shipwrecks around Kelleys Island and the Bass Islands to the west.

Their work, just recently published because of budget cuts, helps the Ohio Department of Natural Resources comply with a state law that orders the agency to inventory, evaluate, protect and designate underwater shipwreck locations.

Archaeologists and historians say they need this information to conserve wrecks as well as provide information to divers and the general public. Side-scan sonar produces images similar to aerial photography, but at an oblique angle.

Geologists already use the sonar to study the lake's bottom. Distinguishing between sand, mud and rock provides insights into fish-spawning areas, beach erosion and mineral production.

"We come across things using the sonar all the time. We wonder if they're ships," Liebenthal said.

The side-scan sonar is lowered into the water on a brace attached to the bow of the division's 25-foot research launch.

It operates just below the surface by bouncing sound waves off the lake bottom. Images are produced as the boat is slowly piloted in a series of precise, calibrated runs over wreck areas.

The sound echoes are recorded in shades of black and gray, depending on how reflective and hard a target is. Scientists look for the straight lines and angles that might indicate a hull or superstructure. Some images are more obvious than others.

The western basin of the lake is fairly shallow, and the waters around the islands are popular with recreational divers. Some wreck sites have been similarly scanned with sonar by private diving clubs.

Still, Lake Erie remains almost totally unexplored. Ohio waters alone contain an estimated 600 wrecks.

"We're pretty far behind in terms of other Great Lake states," said Charles E. Herdendorf, a geologist and archaeological diver who served as a consultant on the study. "The Canadians are way ahead of us in mapping their shipwrecks and opening them up for diving."

The islands area is particularly rich in wrecks, thanks in part to two shoals north of Kelleys Island. Herdendorf estimated that as many as 50 wrecks might litter the lake bottom around the islands.

"If ships got hit by storms, they could easily hit the shoals," said Constance Livchak, a Geological Survey scientist working on the project.

And many did.

Nineteen of the 25 wrecks in the study surround Kelleys, and eight of those went down on the rocks. Only the general locations of most shipwrecks are known. One purpose in searching them out was to fix their exact positions, because wrecks can move with time and the elements. Ice, in particular, acts like a bulldozer.

"The ice covering the lake cracks and grinds together, pushing up and down ... and then it scours the bottom," Liebenthal said.

Five wrecks were recorded on Gull Island Shoal, but the sonar failed to find much of anything left.

Around the islands, wreck sites can be close together. A ship's identity can be uncertain even when sonar reveals a vessel.

For example, images recorded off the northwest shore of Kelleys show either the Oak Valley or the L.B. Crocker.

Sonar also can reveal why a ship went down. The C.H. Plummer, which burned at its dock in 1888, probably was lost to a boiler fire and not to the spontaneous combustion of its cargo of lime, Herdendorf said.

"Where the coal was stored is the only place in the shipwreck where the fire had burned completely through. The rest of the shipwreck was intact," he said. Carrie Sowden, a marine archaeologist with the Great Lakes Historical Society in Vermillion, said she plans to use the data to plan dives at the sites.

Sowden said she wants to confirm wrecks as well as help create dive charts of the lost vessels.

"We'll go out (with volunteers) and see if we can locate them. It could be a shipwreck, a pile of rocks or ballast. It could be anything," she said. "We can learn something about the ship, its construction and maybe why it sank."

Sowden has dived at six wreck sites in the past two years, including the Dundee, a 200-foot schooner barge that went down in 1900 in a storm 14 miles off Cleveland.

"It was under tow. The first thing that happens in bad weather is they cut the tow line. They lost control of it. The barge had no steering," she said.

However, the biggest mystery on the lake for Sowden is one that hasn't appeared on any sonar.

In December 1909, the Marquette and Bessemer No. 2, a 300-foot ferry loaded with railroad cars full of coal, left Conneaut in a gale for Port Stanley. The ferry was never heard from again.

A FISHERMAN at Drumdowney Point has found more than the catch of the day in his fishing nets – you might even call it the catch of six to eight centuries.

Sean Doherty, who lives on the opposite shore in Waterford, was fishing at the south Kilkenny spot about 40 metres from the shore line a year and a half ago, when he noticed in his net what he thought was a flower pot.

On second glance he saw that the pot was unusual in that the bottom was rounded rather than flat like a typical pot of today.

His keen eye for observation has been honed over many years picking up different pieces, and his interest in archaeology has been boosted from watching documentaries and other such programmes.

But little did he know that his discovery would end up on display in the National Museum in Dublin.

He initially brought the pot to the Waterford Treasures museum, and they in turn passed it on to the National Museum.

He still can't believe his luck, as the area has been well fished over the years. "Maybe I was just in the right place at the right time," he said.

Dr Andy Halpin, assistant keeper of the Irish antiquities division in the National Museum, says the pot is an extremely rare find.

The type of cooking pot is referred to by archaeologists as 'Leinster cookware' and this particular pot is a significant find for the museum.

"The type of pottery that it is practically never turns up in one piece, so it's really remarkable," Mr Halpin said. "This is effectively the only intact piece of Leinster cookware that we have."

"How it managed to survive intact lying on the sea bed for hundreds of years and then being brought up in a net, is just amazing."

The pot is about eight or nine inches high and 10-11 inches in diameter, and dates from the 12th to 14th century.

"I couldn't say exactly how old it is but the type of pottery that it is would date it sometime between the 12th and 14th centuries, so it's about 600 to 800 years old," Mr Halpin explained.

"The fact that it's intact is really the main thing about it. Otherwise as a pot it's pretty simple."

The basic pot is a fairly coarse type of pottery, not very refined or well made, he said. It looks slightly like a flower pot and is a pale red terra-cotta colour.

One characteristic feature of Leinster cookware is that quite a large amount of gravel and quartz is included in the pottery, Mr Halpin noted, and the tiny pieces of quartz dazzle when light shines on them.

Such a pot would have been hand-made rather than thrown on a wheel, and was probably fired in a very simple kiln, according to Mr Halpin.

"It is not very technically advanced even for that period," he said. "It's a very humble object. It was probably used by fairly simple people, not the wealthy."

The pot will now be put on display as part of an exhibition on medieval Ireland in the National Museum building on Kildare Street in Dublin.

That exhibition is currently on display and this latest pot will be added to it within the next two months, Mr Halpin said.

Vikings may have used a special crystal called a sunstone to help navigate the seas even when the sun was obscured by fog or cloud, a study has suggested.

Researchers from Hungary ran a test with sunstones in the Arctic ocean, and found that the crystals can reveal the sun's position even in bad weather.

This would have allowed the Vikings to navigate successfully, they say.

The sunstone theory has been around for 40 years, but some academics have treated it with extreme scepticism.

Researcher Gabor Horvath from Eotvos University in Budapest led a team that spent a month recording polarisation - how rays of light display different properties in different directions - in the Arctic.

Polarisation cannot be seen with the naked eye, but it can be viewed with what are known as birefringent crystals, or sunstones.

Birefringence, or double refraction, is the splitting of a light wave into two different components - an ordinary and an extraordinary ray.

The researchers found that the crystals could be used to find out where the sun was in the sky in certain foggy or cloudy conditions.

It is already thought that Vikings used sundials aboard ships to navigate.

Vikings were a seafaring race from Scandinavia who used their longboats to explore and conquer parts of Europe, Greenland, Iceland and Russia.

Shipwrecked on a tiny Indian Ocean island, a group of slaves survived for 15 years before being rescued by the French navy. Now archaeologists have uncovered the shameful history of their extraordinary ordeal. John Lichfield reports

In 1776, 57 years after Daniel Defoe wrote Robinson Crusoe, eight people were rescued from a tiny, treeless island in the Indian Ocean. Seven of them, all women, had survived on the island for 15 years. The eighth, a baby boy, was born there.

The women were the remnants of a group of 60 people who were shipwrecked and then marooned on the scrap of coral and sand in 1761. They were abandoned, and then forgotten, 300 miles from the nearest land, for a simple, brutal reason. They were slaves.

Now, 230 years later, a team of French archaeologists has spent a month searching the wreck of the ship and excavating the flat, shelterless island. They have uncovered some of the secrets of how the castaways clung to life - and developed an elaborate community - on a fragment of near barren land, frequently swept clean by typhoons.

The archaeological investigation, sponsored by Unesco as part of its year commemorating the struggle against slavery, set out last October and November to uncover an almost-forgotten story of man's inhumanity to man. It discovered an extraordinary tale of human tenacity, determination to survive and capacity to organise in the face of adversity.

A French ship, carrying an illicit cargo of slaves, foundered near the island of Tromelin, east of Madagascar, in July 1761. At least 20 sailors drowned. So did 70, or more, of the slaves, trapped below deck because the hatches had been closed or nailed down.

After six months on the island, the remaining sailors completed a makeshift craft and escaped. They promised to return for the surviving slaves, but did not.

The castaways never gave up hope. They kept the same fire going for 15 years, with driftwood and wood from the wreck. They built houses from blocks of coral and impacted sand (the remains of which have been uncovered by the archaeologists). They built a communal oven. They survived on a diet of turtles, seabirds and shellfish.

Max Guérout, a marine archaeologist and former French naval officer, who led the expedition, said: "These were not people who were overwhelmed by their fate. They were people who worked together successfully in an orderly way."

"We have found evidence of where they lived and what they ate. We have found copper cooking utensils, repaired, over and over again, which must originally have come from the wreck of the ship."

"It is a very human story, a story of the ingenuity and instinct for survival of people who were abandoned because they were regarded by some of their fellow human beings as less than human."

Much remains to be found and M. Guérout hopes to lead a new expedition to Tromelin - once known as L'Ile du Sable, or Sand Island - next year.

M. Guérout has also followed a paper trail through the French and British archives of the period. He discovered, among other things, the log book of the Utile (Useful), the French ship which was wrecked on the island in 1761 with at least 150 illicit slaves aboard.

The island, claimed by both Madagascar and Mauritius, has been the site of a French meteorological station since 1953. In 1761, it was just an uncharted speck in the Indian Ocean.

In November of the previous year, the Utile, a former French warship, belonging to the French East India company, set sail from Bayonne in south-west France bound for the "Ile de France", now Mauritius.

France was fighting the Seven Years' War with Britain at the time. The governor of Ile de France was expecting an attack from India. He had banned the import of slaves, fearing they would be further mouths to feed during a siege.

The captain of the Utile dropped anchor at Madagascar nonetheless and bought at least 150 Malagasy slaves. When the ship resumed its journey eastwards, it was caught in a violent storm and ran aground on the submerged coral reef which breaks surface as the island of Tromelin.

A terse, dramatic account of the shipwreck, written by the ship's official log keeper, Hilarion Dubuisson de Keraudic, was discovered by M. Guérout in the maritime archives at Lorient in Brittany.

"The coming of day and the sight of land, which diminished our terrors, reduced none of the furies of the sea. Several people threw themselves into the water with a line to try to reach the land, to no end. A few reached the shore ... We had to haul some others back over the debris, where they drowned.

"We were terrified all the while because the [shattered] stern of the ship, on which we were standing, opened and closed at each moment, cutting more than one person in two."

Eventually, the ship turned its stern towards the shore, allowing the sailors to establish a rope-way to the island.

"All the remaining Gentlemen and crew were saved. Our losses were only 20 white men, and (two gentlemen) and many blacks, the hatches being closed or nailed down." The log book goes on to imply that almost a third of the 88 slaves originally rescued died because the sailors kept the meagre water supplies to themselves.

"We made a big tent with the main sail and some flags and we (i.e the gentlemen) lived there with all the supplies. The crew were placed in small tents. We started to feel very strongly the shortage of water. A number of blacks died, not being given any."

After a couple of weeks, the 122 "gentlemen and sailors" managed to dig a well. At the end of six months, they constructed a small sailing craft from the wreckage of their ship.

The makeshift boat was big enough for the gentlemen and sailors but not for the 60 remaining slaves. They left the captives with some food and promised to return. The Frenchmen reached Ile de France and tried to keep their promise, according to the log book and other French records found by M. Guérout.

The governor of the island, an official of the French East India company, refused to risk the loss of another ship for a group of unwanted and illicit slaves. There was a brief, public controversy in Ile de France. Several local dignitaries tried to persuade the governor to change his mind. He refused. The slaves were forgotten for 15 years.

How did they survive in such an inhospitable place? They had water from the well dug by the sailors. They had some basic cooking implements. The island is, to this day, a breeding ground for turtles and seabirds.

M. Guérout, creator of the Groupe de Recherche en Archéologie Navale, was, however, determined to find out more.

Colleagues warned him that little was likely to remain in the thin soil, or sand, of a flat island which lies in the path of the annual cyclones which sweep westwards across the Indian Ocean. Tromelin is almost literally a "desert island", with a few low bushes but no trees.

M. Guérout insisted that much must remain. He found intriguing references to visits to the island by Royal Navy vessels during the 19th century. The British sailors recorded seeing the remnants of "stone" houses and neatly arranged graves.

A team of 10 French archaeologists and divers lived on the island from 10 October to 9 November last year. Their findings have just been published.

Dives on the wreck of the Utile produced many interesting objects but nothing to advance the story. Digging in the shallow sand and coral of the island produced significant finds.

M. Guérout and his team uncovered the walls of elaborate dwellings, constructed from blocks of coral and from cement-like blocks of compacted sand. They found a large oven. They found remains of the turtles, birds and shellfish eaten by the castaways.

They found copper cooking utensils which had been repaired over and over by the marooned slaves, one of them at least eight times. "They mended them with other pieces of copper, using hand-made copper rivets, forged in the fire of the oven. We even found some of the rivets," M. Guérout said.

The archaeologists failed, to their disappointment, to find the graves mentioned in the Royal Navy records. "They are certainly still there," M. Guérout said. "When we return next year, we will bring better digging equipment and we will find them. Apart from anything else, the island provides us with a unique opportunity to study how a small group of people survived when plucked from their surroundings and left in hostile conditions. Mankind has always been a migrant creature and the island can help us to study the human capacity for adaptation which makes migration possible."

But what happened to the eight known survivors of Slave Island? Actually, there were at least 14 survivors and maybe more.

M. Guérout found French records of the official "debriefing" of the women removed from the island in 1776. They told their French rescuers that, at some point, a group of 18 of the Malagasy castaways made a raft or small sailing boat and left the island. It is not known whether they reached their home island 300 miles to the west or were lost at sea.

In 1776, a French sailor was shipwrecked on the island after spotting the slaves and trying to reach them in a small boat. He helped them to construct a raft and escaped to Mauritius with six people, three men and three women. Soon afterwards, a rescue ship arrived, captained by a nobleman called Tromelin. He gave his name to the island and removed the final group of eight survivors, including a family group of grandmother, mother and child.

By then, a new, more humane governor in Ile de France, appointed by the King of France, not the French East India Company. He insisted that the slaves were not slaves but free people, since they had been bought illegally. He adopted the family of three and gave the baby boy the name Jacques Moise.

"Jacques" was the governor's own Christian name. "Moise" is the French form of Moses - a baby rescued from water.

What happened to little Jacques Moise and the others after that? M. Guérout has searched the records in France and Mauritius without success. He believes that the two groups of known survivors from "sand island" - 14 in all - must have merged into the community of freed slaves in Mauritius. Their descendants are probably living there to this day.

For more information, see the Tromelin dig website: www.archeonavale.org/Tromelin