Burch D. Emergency Navigation: Improvised and No-Instrument Methods for the Prudent Mariner

Camden: Internacional Marine, 2008. — 288 p.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 fogbank
Estimate latitude with a plate and a knotted string
And more vital information