The Kon-Tiki expedition of 1947, led by the Norwegian Thor Heyerdahl (1914-2002), successfully crossed 8,000 km (5,000 miles) of the Pacific Ocean from Peru to the Tuamotu Islands on a balsa-wood raft. The aim of the expedition was to demonstrate that ancient peoples could have crossed the Pacific from east to west using ocean currents and so possibly populated Polynesia. The consensus of modern scientists, however, is that Polynesia was first populated from the west.
Heyerdahl's four-month crossing of the Pacific is one of the most famous examples of experimental archaeology, where theories are put to the test of physical realities. Heyerdahl wrote a bestselling book about this epic voyage, The Kon-Tiki Expedition: By Raft Across the South Seas, first published in Norwegian in 1948 and then in many other languages.
Heyerdahl & Tiki
Thor Heyerdahl was born in Norway in 1914. He studied zoology and geography at the University of Oslo, and, as part of his ongoing research, he and his wife, Liv, lived on the small island of Fatu Hiva in the Marquesas group in Polynesia in 1937. One night, Heyerdahl talked to an old man called Tei Tetua. As they gazed out from the beach to the vast Pacific Ocean, Tei Tetua mentioned that according to oral legend, a chief and sun god called Tiki had been the founder of the population there and that he had come from "a big country beyond the sea" (Heyerdahl, 14). Heyerdahl was struck with the idea that perhaps voyagers from ancient South America had indeed crossed the Pacific. Heyerdahl was also struck by similarities in the monumental sculpture and architecture of Polynesia and South America, and that the Inca civilization of Peru had believed in a sun god Viracocha, once called Kon-Tiki. Scientists in 1947 were not wholly agreed on who had first settled Polynesia. Heyerdahl proposed that settlers came from the ancient Americas. In this, he would be proved wrong, but the migration theory became less important than proving the physical possibility of sea travel over vast distances using only ancient design and materials. As Heyerdahl himself noted, "where science stopped imagination began" (Heyerdahl, 16).
Heyerdahl believed, based on sketches made by the first Europeans in South America, that the ancient people, if they had crossed the Pacific, would have done so using balsa-wood rafts, the craft they had used for centuries to travel up and down the coast. West-direction currents and winds would carry any raft across the Pacific, provided it stayed afloat. Heyerdahl was determined to build his own raft, but in order to prove long sea voyages had been possible in antiquity, the raft would have to be built without using modern techniques and materials. Heyerdahl now faced two groups of sceptics: those who thought his theory of migration nonsense and those who thought the idea of a raft crossing the Pacific suicidal. The Norwegian pressed on regardless and found funding from a newspaper on the promise of future articles and a lecture tour. The expedition was also bolstered by material supplies from other explorers and both US and UK military organisations, which were keen to test items like dried rations.
The Crew
The expedition members were:
- Thor Heyerdahl – expedition leader
- Herman Watzinger (1916-1986) - second in command and recorder of weather data
- Knut Haugland (1917-2009) – radio operator
- Torstein Raaby (1918-1964) – radio operator
- Erik Hesselberg (1914-1972) – navigator and artist
- Bengt Danielsson (1921-1997) – stores management
In addition to the human crew, there was one green parrot called Lorita, a gift from a well-wisher. Behind the scenes on land, Gerd Vold Hurum remained in Peru to perform the role of expedition secretary and project manager.
The Kon-Tiki Raft
The raft was built in the naval harbour of Callao in Peru using large logs of balsa wood cut down in the Quivedo forest in Ecuador. Balsa wood is lighter than cork. The nine main logs measured up to 13.7 metres (45 ft) in length and 60 centimetres (2 ft) across, while the cross-logs measured around 5.5 metres (18 ft) in length and 30 centimetres (1 ft) in width and were placed at intervals of around 90 centimetres (3 ft) on top of the main logs. In keeping with Heyerdahl's insistence on trying to replicate as closely as possible how an ancient raft would have been constructed, the logs were lashed together using hemp rope, and no nails or metal of any kind were used. The bow was made pointed by having the longest log in the centre and progressively shorter ones on either side (the logs were cut straight at the stern)
The deck was made of bamboo matting over bamboo strips. A bamboo cabin (2.4 x 4.25 m or 8 x 14 ft) with a roof of banana leaves provided the crew with shelter from the elements. A limited measure of direction could be achieved via a mango wood steering oar at the rear of the raft, which measured around 4.5 metres (15 ft) in length. The raft had several pine centreboards sunk below the deck to aid stability, and, as it was discovered on the voyage, by raising or lowering these, the raft's direction could be controlled. The raft was given an 8.8-metre (29-ft) high mast consisting of two mangrove wood poles set apart but then bent inwards and tied together at the top. There was a single square canvas sail of around 4.5 x 5.5 metres (15 x 18 ft). Two smaller sails (a topsail and a mizzensail) could also be hoisted in appropriate conditions. Hesselberg painted a giant mask representing Kon-Tiki on the sail, a faithful reproduction of a carving at the ancient city of Tiwanaku on the shores of Lake Titicaca.
Heyerdahl packed four months' worth of rations for the crew onto the raft, but it was hoped their diet of military rations and short-lived fruit, roots, and 200 coconuts would be greatly improved by the regular addition of fresh fish. Some 250 gallons of spring water was carried on the raft in bamboo poles. Each man could fill one box with personal possessions; Raaby had a guitar and drawing paper, Danielsson brought along 73 books.
As the raft floated ready for departure, various experts and officials visited and confidently informed Heyerdahl that the logs would become waterlogged and the craft would break up before he had completed one quarter of his epic voyage. Hurum christened the raft Kon-Tiki by smashing a coconut against it.
A Worrying Start
The Kon-Tiki set off from Callao on 28 April 1947. Picked up by the Humboldt current moving northwards, the raft, despite the heaviest seas of the voyage, proved a stable craft that easily rode over the large waves, as Heyerdahl explains:
We saw a white crest come groping towards us on a level with the cabin roof, we held on tight and waited uneasily to feel the mass of water smash down over us and the raft. But every time there was the same surprise and relief. The Kon-Tiki calmly swung up her stern and rose skyward unperturbed, while the masses of water rolled along her sides.
(81)
The heavy seas eventually calmed down as the raft got further from the coast. Well settled in the Humboldt current, the problem now was how far north would the raft drift before it was carried westwards? What Heyerdahl did not want was to be carried too far north and then west to hit the Galapagos Islands, which were surrounded by dangerous counter-currents. Another concern was the constant movement of the individual logs, putting stress on the lashings that held the raft together. As the ropes became more soaked and so swelled, they became a little tighter, and the movement was reduced, but sleeping on the Kon-Tiki still felt "as if one was lying on the back of a large breathing animal" (Heyerdahl, 86).
Another worry was the rate at which seawater was soaking into the logs, making them heavier so that the raft was perceptibly lower in the water. Pieces of watersoaked balsa wood could be pulled off the log exteriors, pieces which sank without a trace. The interiors of the logs were still dry, but for how long?
As the weeks went by, it became clear the raft would not fall apart as every expert had predicted. The Kon-Tiki rode the waves but, crucially, did not resist them. The lashings gradually worked into the balsa logs and so became better protected from wear and tear by the elements. Even the soaking of the logs seemed to be slowing. Frustratingly, though, the Kon-Tiki was still not catching the westward South Equatorial Current.
Mid-Ocean Life
Slowly, the raft began to drift west-northwest, and the sea colour changed from green to deep blue. Kon-Tiki had finally caught the first movements of the South Equatorial Current while the sail captured light trade winds. Fresh food often proved remarkably easy to come by as the raft drifted across the Pacific. This diary entry by Heyerdahl illustrates the point:
17th May. Norwegian Independence Day. Heavy sea. Fair wind. I am cook to-day and found 7 flying fish on deck, one squid on the cabin roof, and one unknown fish in Torstein's sleeping bag…
(11)
After a light was set against the sail at night, a dozen or more flying fish would throw themselves onto the raft. The fish were fried for breakfast using the expedition's Primus stove. Sea life of all kinds came to explore the slow-moving raft. Dolphins, porpoises, sharks, and countless unidentifiable fish would follow the Kon-Tiki for days, perhaps curious to see what this new shadow was in the usually undisturbed waters. Under the raft, a garden of seaweed grew, which hosted crabs, barnacles, and other crustaceans. At night, phosphorescent plankton and giant luminous squid would appear from the ocean's depths.
Life below the surface was the only source of change as the raft drifted across the Pacific. At the mid-way point in the voyage, Heyerdahl recalls:
The weeks passed. We saw no sign either of a ship or of drifting remains to show that there were other people in the world. The whole sea was ours, and with all the gates of the horizon open real peace and freedom were wafted down from the firmament itself.
To us on the raft the great problems of civilised man appeared false and illusory, mere perverted products of the human mind. Only the elements mattered. And the elements seemed to ignore the little raft. Or perhaps they accepted it as a natural object which did not break the harmony of the sea…the elements had become a reliable friend which steadily and surely helped us onward.
(97)
After two months at sea, the water supply from Peru began to go off, but it was easily replenished by collecting water from regular rain showers. The raft kept on course, its position verified by daily sextant readings. One day, Lorita the parrot was washed overboard and lost; it was a stark reminder of what would happen to any member of the crew if they slipped off the raft. Despite the risks, a dinghy was let out on a long rope so one man could photograph and film the raft at sea, an essential visual element for the planned documentary of the expedition.
The raft was following the current and winds in a giant curve across the Pacific. As it closed in on the island groups of Polynesia, the weather became less predictable. One storm brought waves the height of the mast, but "the Kon-Tiki took everything that came her way with ease and buoyancy" (Heyerdahl, 155). In another storm, Haugland saved Watzinger from drowning after the latter was washed overboard. The storm, which lasted five days, took its toll on the raft. The lashings became a little looser, and the raft now creaked and groaned. The Kon-Tiki was still seaworthy, but the crew began to wonder where and when they would hit land. The course the Kon-Tiki was taking might ensure it landed at the Marquesas Islands or the Tuamotu Islands, both still 300 sea miles away. Both groups had their problems: it was not easy to strike a beach amongst the perpendicular cliffs of the Marquesas group while the Tuamotu islands were ringed with dangerous coral reefs. Then again, if they were unlucky, the raft might drift between the two groups and head deeper into Polynesia.
Polynesia
On 16 July, two booby birds approached. The species of flying fish throwing themselves on board were now different, too. These were signs that land was not far away. The winds began to pick up while the Equatorial Current now faded: the Kon-Tiki was heading towards the Tuamotu group. Over the next few days, more birds came to circle the raft and then fly on. On 29 July, a low cloud could be seen on the horizon, perhaps an indication of an island ahead. The winds and local current strengthened, and the Kon-Tiki could not be turned to a low island a few sea miles away, identified as Puka-Puka, a tiny coral atoll on the far northeastern edge of the Tuamotu group. Several more islands were seen at a distance in the next few days until one was spotted dead ahead with a narrow beach and forest of palm trees. Heyerdahl noted, "we should never see a more genuine South Sea island" (175).
The crew hoisted all the flags on board and made ready to hit land. Joy and expectation were mixed with unease at how the Kon-Tiki would broach the submerged coral reef that ringed the island. The sea was positively wild when it hit the coral, and the suction created could easily break up the raft before it made the safe, calm waters of the inner lagoon. The crew looked for a gap in the reef but to no avail. Then, an outrigger canoe headed out from the beach. Some island residents had spotted the raft and came to show a gap in the reef. An islander shouted the two words he knew in English: "Good night!". By gesturing, the way through the reef was shown, but the raft could not make it and drifted off toward another island. A few days later, Kon-Tiki reached the Raroia reef, which has many small islets behind it.
There was nothing to do but try and scrape the raft over the Raroia reef. Everything was lashed down, valuables put in waterproof bags, a makeshift anchor made, and the centre boards pulled up. The Kon-Tiki ran aground on 7 August 1947. After 101 days at sea, the raft was wrecked and stuck fast on a coral reef. The Kon-Tiki had travelled almost 8,000 kilometres or 5,000 miles, averaging a gentle speed of 1.5 knots (2.8 km/h or 1.7 mph). Bashed and bruised, Heyerdahl and his crew waded across the lagoon to an island
…with palm tops rising into the sky and snow-white sandy beaches running out into the still lagoon. The whole island looked like a bulging green basket of flowers, or a little bit of concentrated paradise…I was completely overwhelmed. I sank down on my knees and thrust my fingers deep down into the dry warm sand.
(196-7)
Legacy
Heyerdahl's book of the expedition quickly became an international bestseller with tens of millions of copies sold, multiple new editions, and translations into more than 70 languages. The film of the expedition, which included extensive footage taken by the expedition members, won the 1951 Academy Award for Best Documentary Feature. The Kon-Tiki raft, rescued from Raroia, is today on public display in the Kon-Tiki Museum in Oslo, which opened in May 1950.
The Norwegian experimental archaeologist was not successful in convincing the academic world of his migration theory. Modern scientists working in a wide range of fields such as archaeology, genetic research, linguistics, ethnography, and ethnobotanical studies have reached a consensus that Heyerdahl's theory of Polynesia being populated by groups travelling from South America was wrong and that they were, instead, populated by peoples moving from island to island groups, moving west to east. Nevertheless, there is DNA evidence proving intercultural travel since tests conducted on both sides of the Pacific have revealed that at least some South Americans must have travelled to Polynesia and some Polynesians must have travelled to South America, even if in neither case did they found new and lasting settlements.
Heyerdahl's own expedition certainly helped demonstrate that ancient peoples may have been more mobile than previously imagined and that very simple craft using ocean currents could have allowed extensive sea travel. Craft such as the Hōkūleʻa, a double-hulled canoe with sails, built according to Polynesian tradition in the 1970s, have demonstrated beyond doubt that ancient peoples had more sophisticated craft than previously thought and could both navigate precisely and sail against the wind. The Hōkūleʻa, for example, has even circumnavigated the globe.
Heyerdahl continued to lead expeditions involving experimental archaeology such as the construction and sailing of reed boats in the Ra (I and II) and the Tigris expeditions, successfully crossing the Atlantic Ocean and Indian Ocean, respectively. As the explorer noted in an introduction to a new anniversary edition of the Kon-Tiki Expedition: "The Kon-Tiki expedition opened my eyes to what the ocean really is. It is a conveyor and not an isolator" (Graham, 179).
