Celestial and Natural Navigation - What Is It?

I'm one of the things I'm fascinated about are different phenomena of the ocean, observing seabirds and paying attention to the swell. In the Caribbean, it's really easy when you're sailing in the leave in Ireland, even if it's 80 miles away, you can feel the waves diminish. But the Polynesian navigators could actually feel the waves refract. So things like that, lots of star-based stuff.