The Navigation Foundation Every sailor knows that instruments can fail. Things get wet, break, fall overboard. Whether you're safe on your boat or drifting in a life raft, let David Burch show you how to find your way no matter what navigational equipment you have. Often relying on common materials like a small stick, a plastic bottle, even a pair of sunglasses, Burch explains how to make use of all available means--from the ancient skills of Polynesian navigators to the contrails of airliners overhead--to calculate speed, direction, latitude, and longitude and to perform all aspects of piloting and dead reckoning. Learn how to: steer by sun, stars, wind, and swells. Estimate current and leeway. Improvise your own knotmeter or plumb-bob sextant find the sun in a fog bank estimate latitude with a plate and a knotted string and more vital information.