Six men on a raft: The Kon-Tiki sailed from Peru to Polynesia in 101 days in 1947.

AP Photo __1947: __ Thor Heyerdahl and five crewmen leave Callao, Peru, on a balsa-wood raft. They're hoping to prove that ancient South Americans could have sailed to Polynesia.

Heyerdahl was a Norwegian adventurer and ethnologist who crossed the boundaries of academic disciplines and ruffled plenty of feathers in the process. He theorized that South Americans had visited and traded with Polynesia, not that they were the primary population source. Scholars derided him and maintained that South American balsa-wood craft would get waterlogged and sink before they could cross the Pacific.

So Heyerdahl built the Kon-Tiki and named it after the pre-Inca sun god. The 18-by-45-foot deck was made of nine balsa trunks lashed with hemp rope. A 29-foot A-frame mast held a 15-by-18-foot mainsail and a topsail. The raft also had a mizzen sail and a long steering oar at the stern. A small cabin and some of the deck were made of bamboo. No metal was used in the construction.

Kon-Tiki had a few concessions to contemporary life: radio, life raft and modern food. Heyerdahl said the purpose of the voyage was only to test the raft: "We were not making it to prove that we had once been Indians ourselves." Huge Pacific swells regularly broke across the raft's flat surface but did not swamp it. The journey covered 4,300 nautical miles in 101 days (averaging 42½ miles a day). The raft suffered no real damage until it landed on the reef in the Tuamotu Islands on Aug. 7.

Heyerdahl wrote a best-selling book that was translated into 65 languages. The film version of Kon-Tiki won an Academy Award for Best Documentary of 1951.

Heyerdahl may have proven that ancient mariners could have sailed westward across the Pacific, but he didn't prove that they had done so. Most scholars conclude that the Polynesian Islands were settled from the west, based on evidence from linguistics, genetics and cultural anthropology.

Still, the Kon-Tiki and Heyerdahl's subsequent adventures in the Atlantic opened the scholarly and popular imagination to the possibility that some of our ancestors may have made adventurous journeys in many places long before we previously suspected.

(Source: Donald P. Ryan, others)

Passage, Thor Heyerdahl, 87

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