“The Polynesians, scattered as they are over islands across the central and southern Pacific Ocean, are master navigators who tracked their way over a huge expanses of ocean without any of the complex mechanical aids we associate with sea navigation. They didn’t have the astrolabe or the sextant, the compass or the chronometer. They did however have aids of a sort, which though seemingly humble, were in fact the repositories of an extremely complex kind of knowledge. They are called Rebbelibs, Medos. and Mattangs.”
http://kurungabaa.net/2010/07/12/navigating-by-touch/
Below is a documentary about the Polynesians as well.