Kon-Tiki in Reverse:

The Tahiti-Nui Expedition

Section 1

1: De Bisschop’s critique of Kon-Tiki

2: De Bisschop’s “Maritime Ethnology”

Section 2

1: Testing the seaworthiness of bamboo

2: Building the Tahiti-Nui

Section 3

1: The Tahiti-Nui Expedition: False Starts and Archaeological Islands

2: Eastward towards Easter Island

3: Towards South America and destruction



Eric De Bisschop (from his book Tahiti-Nui).




















































































































































































































Eric De Bisschop’s Tahiti-Nui (after Danielsson, 1960).





































The route of Tahiti-Nui and other raft expeditions after Kon-Tiki.



Section 1: The remarkable Eric de Bisschop


1: De Bisschop’s critique of the Kon-Tiki theory


Thor Heyerdahl’s idea of a bearded white god-man bringing civilization to Polynesia from the direction of the rising sun did not sit well with many Pacific islanders.  The first direct and sustained Polynesian drifter’s challenge to the Norwegian came from a French baron living in Tahiti.  By his own admission, Eric de Bisschop had invested the better part of thirty years in a study of Polynesian navigation and anthropology prior to his 1956 voyage in a bamboo raft.  But de Bisschop was far more than an armchair explorer.  Prior to his raft expedition, a case can be made that only James Cook himself had sailed more of the Pacific Ocean in search of scientific truth than Eric de Bisschop.

Like William Willis, Eric de Bisschop was in his sixties, and had already spent much of his life at sea, before living the last years of his life on rafts.  In the 1930s, after four years in China, de Bisschop had saved enough to purchase an old Chinese junk, the Fou-Po.  When a cyclone wrecked this ship off the coast of Taiwan, he built a second, the Fou-Po II.  On board this second junk, after wrecks in Australia and New Guinea and attacks by wood-eating marine worms called teredo navalis, de Bisschop explored whether the 9,000-mile long equatorial counter-current could have served as a prehistoric seaway between Asia and America. 

Just before the Second World War, he built a Polynesian double-hulled canoe he named Kaimiloa, and sailed it from Hawai’i to France.  Kaimiloa raced through the first 2,300 miles from Honolulu to the Wallis Islands in little over a month, then crossed the 6,000 miles of the Indian Ocean in less than two.  These were extraordinary reaches, and convinced de Bisschop that watercraft of Polynesian design were the equal of any ocean distance anywhere.

Settling in Tahiti after the war, de Bisschop was called back to the sea by the success of Kon-Tiki.  Two aspects of Heyerdahl’s voyage in particular bothered him mightily.  First, Heyerdahl’s raft, presumably a copy of the pre-Columbian sailing raft, was built with fixed centerboards.  De Bisschop knew this not to be the case: these centerboards had been designed to be moved up and down according to the navigational needs of the raft, a fact Heyerdahl himself learned in 1952, five years after his first raft trip.  Similar centerboards are used to control the movements of bamboo rafts of ancient design in Taiwan and the coasts of China and Viet Nam.

These centerboards, or guaras, allowed one to tack and cross a raft into the wind like any European sailing vessel.  As Heyerdahl wrote in 1994 to my colleague John Haslett, then planning the first of his three balsa raft voyages, “balsa rafts of from 3 to 5 balsa logs are still used in several fishing ports in both Ecuador and north Peru, and they go out at night and come back to the same beach by noon” (Heyerdahl 1994).  Long before Heyerdahl’s experiments with the guaras, Eric de Bisschop met Kon-Tiki crewmember and anthropologist Bengt Danielsson in Tahiti after the expedition, and Danielsson had to admit that the centerboards had likely not been employed properly. 

Much more than this esoteric question of raft design, however, was the suggestion that Polynesian’s could not have reached the shores of South America because the prevailing winds and currents would have effectively prevented such a passage.  This de Bisschop refused to accept.  He himself had tacked Chinese junks and double-hulled canoes against the prevailing winds for much of his life, and saw no reason why prehistoric Polynesians could not have accomplished the same thing.  What was startling, however, was the technology de Bisschop chose to employ in an attempt to refute the Kon-Tiki theory.

When Bengt Danielsson arrived in Tahiti for the fifth time in the fall of 1956, he saw a raft moored along the docks of Papeete in the same spot where he and the rest of Heyerdahl’s crew had stepped off Kon-Tiki almost ten years earlier.  But this was a raft of a very different sort.  Again like William Willis before him, de Bisschop had distilled a lifetime of sea-going experiences into the design of a transoceanic raft.  In de Bisschop’s case, his raft reflected his experiences in Polynesia and China, as well as his knowledge of Chinese and Peruvian centerboards. 

The raft was built of bamboo, equipped with Peruvians guaras, and rigged like a double-masted Chinese junk.  Remarkably, rather than use all his accumulated experience to demonstrate that a true Polynesian double-hulled voyaging canoe could manage a journey from Tahiti to South America, de Bisschop proposed that his polyglot bamboo raft could make the same voyage against five thousand miles of prevailing winds and currents.  He advanced his proposal to general disbelief.  When he announced that he would set his course far to the south, to take advantage of the shifting westerly winds and currents that prevail around 40° south, most sailors thought the expedition a suicide.  Any raft caught in the cold and “roaring forties,” they argued, would be quickly torn to pieces.

To de Bisschop’s credit, he was merely taking anthropological theorizing to its logical conclusion.  Like prevailing winds, the prevailing anthropological view was one of an ultimate Southeast Asian origin for Polynesian culture.  De Bisschop on the other hand, considered the “Polynesian problem,” as it was often referred to, far from solved.  Like Heyerdahl, he had no time for academics with no practical maritime experience upon which to base their theories of Polynesian origins and migrations.  Heyerdahl had had the courage to put his raft where his theory was.  For this reason, and this reason alone, de Bisschop told Bengt Danielsson that he had more respect for Thor Heyerdahl than all his other opponents put together. 



2: De Bisschop’s “Maritime Ethnology”


In de Bisschop’s view, if anthropologists wanted to understand the essentially maritime culture of the Polynesians, they had better start to understand the nature of the maritime world.  That meant a vast expansion of scholarly geographic horizons, and a total abandoning of the idea (still subconsciously prevalent in many academic discussions) that the geography of the Pacific has remained unchanged since time immemorial.  De Bisschop railed against anthropologists who “blandly assume that the geographical features of the Pacific and Indian Oceans, with all the lands which emerge from them or border them, have not budged an inch for thousands of years—an assumption based on nothing except perhaps man’s subconscious reluctance to admit that he inhabits an unstable and ever-changing crust” (de Bisschop 1959, 7).

 Bisschop saw a Polynesian sphere of influence extending from Easter Island and perhaps the shores of South America in the east, to Madagascar off the coast of Africa in the west, a span more than half the distance around the world.  No other peoples could claim such enormous dispersions.  For de Bisschop, no outsiders had taught Polynesians to sail, rather it was the Polynesians themselves who, by spreading their seagoing knowledge from Indonesia and India and then all the way to Madagascar, had accomplished quite the reverse.  He imagined the Polynesians visiting South America before the time of Christ, to return with plants common to both places.  And this nearly two thousand years before Europeans made tentative voyages with the currents and winds from Spain to the Caribbean.  With such a tradition, de Bisschop proposed rewriting the maritime history of the world, with the Polynesians in their rightful place at the center of that history.

To study this enormous problem, de Bisschop envisioned as well a new field of maritime ethnology, where scholars would use recreated voyaging technologies in order to study ancient diffusions.  That genetic evidence now points to the likelihood of transoceanic migrations to Madagascar originating in the Pacific, and that experiments in long-distance voyages by recreated Polynesia canoes are now integral facets of maritime anthropology, only reinforces de Bisschop’s pioneering and little appreciated role in Pacific studies.  Like Heyerdahl before him, de Bisschop believed that no attention would be offered to his ideas unless his took them to sea, on an actual transoceanic voyage.  His bamboo raft would be the instrument of his attack on academic convention. 

Like Danielsson, many wondered why de Bisschop would choose a raft for his experiment, rather than the double-hulled and double-outrigger canoes he was so familiar with.  De Bisschop was clearly stung by this repeated criticism.  He countered that, in his studies of Polynesian navigation, a maritime culture as sophisticated as that of the Polynesians, surely would have possessed different vessels for different missions.  He imagined that single outrigger canoes were appropriate for skimming over shoals and reefs; much larger double-hulled and double-outrigger canoes would have been used for quick hit-and-run raids on neighboring tribes or voyages to known destinations. 

But for long-distance voyages of exploration and colonization, with their essential cargoes of people and provisions, only large rafts would suffice.  And as de Bisschop saw it, when equipped with the moveable centerboards called guaras, these rafts became sailing vessels capable of true navigation.  “It was by no means a floating contraption at the mercy of winds and currents” (de Bisschop 1959, 34-35).  Furthermore, the slow speed of a raft voyage, de Bisschop imagined, was no hindrance for a Polynesia people with a fundamentally different view of time. 


Section 2: Testing Bamboo and Building the Raft


1:  Testing the Seaworthiness of Bamboo


To test whether Tahitian bamboo could remain buoyant for the duration of a long ocean voyage, de Bisschop had a diving platform constructed from bamboo and moored near a friend’s house for a year.  While some of the bamboo was eventually attacked teredo navalis, the platform was still afloat after a year.  As for whether or not Polynesians ever used bamboo rafts, de Bisschop was unequivocal.  He cited several voyages on bamboo rafts navigated by prehistoric Marquesans fleeing tribal wars.  Some of these bamboo rafts, constructed with five layers of bamboo logs, ventured as far as Tahiti and even Hawai’i. 

In building the raft, de Bisschop had little to go on in the way of local knowledge.  If bamboo rafts had ever been used in Polynesia, they had long since become distant memories.  So he relied instead on his knowledge of sailing, on the assumption that, confronted with similar building materials on the same ocean, ancient Polynesians would have come to the same nautical design conclusions. 



2:  Building the Tahiti-Nui


When the bamboo was ready, it was lashed together with coconut fibre rope.  The sails de Bisschop had plaited from vegetable fibres.  Once finished, he christened the whole creation Tahiti Nui, Great Tahiti.  The one concession to the twentieth century was a cabin made of double walls of plywood, which housed an echo sounder, radio, a darkroom, and a dry sleeping area for the crew.  Unlike Bombard, whose voyage de Bisschop cited, he had no desire to conduct a human endurance test, “to be made to swallow plankton and other revolting stuff of that sort, to drink sea water or the juice squeezed out of raw fish” (Ibid, 109).  De Bisschop himself was sixty-five years old and debilitated by bronchitis and emphysema.  His doctor told him in no uncertain terms that he would not survive the journey, a knowledge that bothered de Bisschop not at all. 

By de Bisschop’s reckoning, the last great voyages by a Polynesian fleet had taken place some 700 years earlier, during the fourteenth century.  On November 8, 1956, he prepared to follow that fleet to sea, on a strange polyglot raft at the start of an even stranger scientific experiment.  De Bisschop reckoned that the voyage to South America would take between three to four months.  Provisions were stowed for five, “beer and lemonade    a dozen enormous stems of bananas, numerous sacks of potatoes, kumara, onions, taporo, gourds, not to mention mountains of coconuts both green and dried” (Ibid, 105).  Any longer than on a raft and de Bisschop feared the consequences.  “It is not only bamboo that begins to degenerate after seven months at sea,” he wrote laconically (Ibid, 93).


Section 3: The Tahiti-Nui Expedition


1: False starts and Archaeological Islands


Like all previous raft expeditions, Tahiti-Nui began with a tow by a diesel-powered ship to its place a departure.  Fifty outrigger canoes escorted the raft from Papeete harbor, perhaps unconsciously suggesting a method by which prehistoric rafts were maneuvered off the beach and into position to take advantage of wind, tide, and current.  Even before clearing Tahiti, de Bisschop became concerned with the raft’s buoyancy, and decided to put ashore to lay in additional bamboos for the long voyage ahead.  The same gunboat that had towed them out, now returned to tow them back in.  To Alain Brun, de Bisschop’s second-in-command, the gunboat saved them all from embarrassment when it “mercifully took us to a remote creek on the south coast of Tahiti” (Danielsson 1960, 63).  Thus reinforced, the raft started south toward the Austral islands of Rurutu, Raivavae, Tubuai, Rimatara, and Rapa, making three and a half to four knots of speed on a following wind that lasted for a week. 

            At this early stage of the experiment, the raft surprised even de Bisschop by its ability to use its guara centerboards to make a passage toward the southeast.  Before the voyage, de Bisschop thought the best the raft might do was approach his own Austral island of Rurutu.  Now he found himself approaching the seas that separated Raivavae and Tubuai, more than 200 miles east of Rurutu. 

Heyerdahl had just called at many of these islands after his work on Easter Island.  William Mulloy had carried out extensive archeological excavations at the spectacular aerie at Morongo Uta, one of twelve entirely unexplored mountaintop fortresses on Rapa Iti.  Arne Skjølsvold, the Norwegian archaeologist who had discovered the inscrutable “kneeling statue” of Easter Island, spent several weeks mapping the ceremonial marae platforms of Raivavae.  Contrary winds now blew the Tahiti-Nui in a complete circle around Raivavae.  A few weeks later the raft passed the latitude of Rapa Iti, and so moved beyond the limits of French Polynesia.  As 1956 turned to 1957, 5,000 miles of cold open sea lay between the raft and its destination in Chile. 




2: Eastward towards Easter Island


Beyond Rapa, at about 33° south, the raft picked up shifting west winds and de Bisschop set his course directly eastward to South America.  For two months, Tahiti-Nui careened furtively eastward in tolerable temperatures that hovered between 68°-77° F.  On February 23, 1957, the raft passed the longitude of 117° W, the halfway point on its voyage.  But the mark brought little consolation.  The experiment was now three and a half months old, at a point when de Bisschop had believed they would be safely ashore in Chile.  Instead, the bamboo, put in the water in September, had been afloat now for more than five months.  It was approaching the limits of its buoyancy with still more than 2,500 miles to go.  The crew, to the contrary, thought the worst was over, that the remaining miles would speed by.

Instead, they were met almost immediately by a dreadful fortnight of winds blowing from the east.  De Bisschop had told Bengt Danielsson that he intended to sail down to 40° south, where he would be assured of steady winds and currents from the west.  But now he hesitated, staying in an area of wavering winds around 35° south.  Even here the seas were rough, and de Bisschop was convinced Tahiti-Nui would lose its two masts if he tried to sail any farther south. 

Ben Finney, for one, believes it was the only decision de Bisschop could have made.  At 40° south, the raft would have been torn apart by mountainous seas.  If prehistoric Polynesians had voyaged along this route to the east, they did so only at great risk to themselves and their expeditions.  Even at 35° south, heavy winds forced de Bisschop to take in most of the sail the raft carried, to prevent it from being carried away. 

When the raft began show signs of breaking up in late February, de Bisschop was forced to put down a minor mutiny by the three other crewmembers.  All were half de Bisschop’s age and cared little for the scientific substance of his experiment.  They advocated instead an audacious retreat as far as 50° south in an attempt to speed their passage.  Daily radio interruptions suggesting steady winds further south—and thereby further enticing the demoralized crew in that deadly direction—nearly drove de Bisschop to pitch the set overboard.  When the raft circumscribed a complete circle on March 11, returning the crew to a point they had passed seventeen days earlier, morale sank even further.

One unexpected advantage of de Bisschop’s more northerly course was a near miss of Easter Island during the first week of March.  The seagoing raft wandered to within 350 miles of anthropology’s most enigmatic island on March 7, 1957, demonstrating a plausible access route from the west to this most remote corner of Polynesia.  De Bisschop in fact began to spin a theory that the island had been originally colonized by a raft caught in the same contrary winds his raft now endured.  His crew wished he would follow his own hypothesis and make for a landing at Easter Island, at the very least so that repairs could be made to the raft. 

Had de Bisschop done so, it is likely that the voyage of Tahiti-Nui would have taken a rightful place alongside Kon-Tiki as one of the great Pacific drift voyages, and ironically increased its value to maritime anthropology.  Tahiti-Nui had linked the Austral islands of Rapa Iti and Raivavae, with their stone fortifications and ceremonial marae platforms, with the stone ahu platforms and carvings of Easter Island.  The raft had voyaged almost as far as Kon-Tiki, and remained afloat for more than six months, four of them on the high seas.  By continuing eastwards to certain destruction, de Bisschop weakened the plausible case he had already made for the efficiency of the long-distance seagoing bamboo raft in prehistoric Pacific expeditions.



3: Towards South America and destruction


The destruction of Tahiti-Nui arrived in slow and painful measures.  The raft drifted through April as the crew suffered through a near-total lack of fresh water.  May brought with it fresh winds from the west, but the raft was still a thousand miles from Chile. A week later, still eight hundred miles from the coast, the big four-inch main bamboo logs began to break away in fifty mile an hour winds.  The situation now became desperate, with the raft listing heavily.  To worsen matters, de Bisschop found his bamboo hull “riddled with tunnels the size of your little finger, each one with its fat white [teredo navalis] worm.


“They have wicked heads with two hard curved plates at the business end, only too well designed for the dastardly work of boring and destroying.

“I have seen natives, especially in Melanesia, reveling in these large white worms, which they eat raw.  Here, now, is a field of survey which has been ignored by the specialists—something to add to the menu of those who cast away at sea.  I myself had never thought of it.  I wish I had; it might have been most useful when, on Fou Po II, I went for nearly three weeks [without food].  But how I could have harvested the little beasts into the frying pan when they were snug below the waterline in the very planks of the hull which kept the boat afloat, I don’t know” (Ibid, 185-86).


By the middle of May, after six months at sea, even de Bisschop was tired of the cold southern seas, and began to long for the warm and light blue waters of Polynesia.  When a severe storm forced the crew to abandon the idea of a landing at the Juan Fernandez islands off the coast of Chile, where Alexander Selkirk had found himself marooned in 1703, de Bisschop at last signaled for a tow.  Over their radio they listened to spurious reports that the raft had been dismasted, that the crew was injured by the attack of a giant fish, that giant molluscs had attached themselves to the raft and were dragging it down.  The expedition had taken on a distinctly Vernian tone.

The raft plowed on to its farthest point east: 87° 54’W.  Winds then forced it back more than a degree to the west, where a Chilean naval vessel caught up with it on May 22, 1957.  The unsuccessful tow resulted in the final break-up and abandonement of the raft on May 26th.   As the starboard tiki god figure, carved by a Marquesan artist, was salvaged from the raft, de Bisschop heard the final sickening splintering of the bamboo.  On board the Chilean ship, de Bisschop took to a bunk and lamented his failure to prove his theory.

Once ashore in Chile, de Bisschop began writing up his experiences on board the Tahiti-Nui.  Now, at the age of sixty-six, he was more determined than ever to complete a full-circle voyage from Tahiti to South America and back.  On February 15, 1958, a new raft, christened Tahiti-Nui II, was prepared to drift from South America to Polynesia, along the track pioneered by the balsa rafts of Thor Heyerdahl and William Willis.  It would prove to be the final expedition in the long, adventurous life of Eric de Bisschop, when this new expedition led to de Bisschop’s death on the reef at Rakahanga.