The Practical Mariner's Book of Knowledge: 420 Sea-Tested Rules of Thumb for Almost Every Boating SituationBetween these covers is the essence of centuries of seafaring experience, distilled into a concise, alphabetically organized reference for sailors and powerboaters. You'll find rules of thumb for hull thickness, bottom paint coverage, estimating distances, when to hoist and lower flags, predicting weather, which colors are unlucky, rope size and strength, anchoring rights, making a rum punch, and a lot more. This is either the most useful boating book