Global Positioning System Reference
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way a further 2,000 km eastward, to the Marquesas Islands in French
Polynesia. This entire region is characterized by low-lying island groups
spread thinly across featureless ocean, so that many of these colonizing
voyages took place out of sight of land. From the Marquesas, these seafarers
(for simplicity, I will call them all South Sea Islanders) boxed the compass:
they spread northward, reaching the isolated Hawaiian Islands by about
400 CE. 13 Heading southwest for a couple of thousand kilometers they
reached New Zealand between 1250 and 1300 CE. Heading eastward from
the Marquesas, they colonized Easter Island (Rapa Nui), probably around
1200 CE. Some argue that they didn't stop there but continued eastward
and settled, at least temporarily, on the Pacific coast of South America.
The boats that these South Sea Islanders traveled in were outriggers—
open catamarans with a single sail (fig. 5.5). The navigators were specially
trained over long periods, and they found their way around their wide-
spread island groups by skillful seamanship and navigation based upon
careful observation. None had any navigational tools, apart perhaps from a
simply constructed aide-mémoire. How did they do it?
We know quite a lot about the South Sea Islanders' navigation tech-
niques because they are still practiced today, though the knowledge is
dying out in the GPS age, and the practice is now perpetuated mainly for
cultural reasons. Long voyages were planned far in advance and prepared
meticulously. The voyagers would take enough provisions for two months
at sea. Their large catamarans could travel 150 miles (about 250 km) per
day, and so they were able, in principle, to travel right across the Pacific
without stopping for provisions. The navigators, unsurprisingly perhaps,
given that many lives depended on them, constituted an elite fraternity.
They were taught their craft from childhood: a boy of five or six years
would begin to learn the star structures, and he might be put in charge of
his first long voyage at age 18 or 20. (Of course, the teachers themselves
were experienced navigators, perhaps too old for arduous sea journeys.)
The boy had a lot to learn.
The horizon was divided into 32 points, as is our compass. Stars were
associated with each point. A novice navigator would learn which stars
rose and set at each compass point at di√erent times of the year. Addi-
tionally, for insurance (in case of cloud cover) he would learn the stars
opposite (for instance, the rising of Antares in the southwest is opposite to
13. In fact, archaeological evidence suggests an earlier occupation around 300 BCE, but
this first wave either did not survive or was swamped by the later arrivals.
 
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